Physics
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Item A study on Einzel lens design and fabrication for a microcolumn(2013) Suwal, Om Krishna; Ho Seob Kim whoseAvailable in fulltextItem Radiation Shielding Properties of Few Natural Rocks(Amrit Campus, 2024-11-12) Uddab Bahadur Bhandari; Dr. Raju KhanalFull Text AvailableItem Energy Eigenvalue and Thermodynamic Properties of Deng-Fan Screening Potential with Ab-Field(Amrit Campus, 2024-08-02) Ramkripal Sharma; Kishori YadavFull Text AvailableItem Effects of Collesion Frequency and ION Mach Number on Electro Negative Megnetized Plasma Sheath(Amrit Campus, 2022-04-22) Ishwor Datt Bhatt; Roshan ChaliseFull Text AvailableItem Radiation Shielding Properties of five Clay Bricks(Amrit Campus, 2024-09-15) Birendra Khadka; Dr. Raju KhanalFull Text AvailableItem Force Field Analysis of Guanosine 50-Diphosphate and its Binding Mechanism with the 1git Protein(Amrit Campus, 2024-02-10) Bhupendra Maharjan; Dr. Manoj Kumar ChaudharyFull Text AvailableItem A theoretical study of excitation cross section for helium atom and calculation of its ground state energy(2010) Kushwaha, Dhanik Lal; Jeevan Jyoti NakarmiAvailable in fulltextItem Enhancing Agricultural Productivity by using Cold Atmospheric Pressure Plasma(Institute of Science & Technology, 2024-10) Chalise, Roshan; Prof. Dr. Raju Khanal, Dr. Bhagirath GhimireIt is well known that various technologies are being used and researched to increase the productivity of essential food and agricultural products due to the gradually increasing population, decreasing arable land, and climate change. For the past few years, various research works have been carried out to increase agricultural production, improve the quality of seeds, increase plants as well as preserve the produced fruits for a long time without letting the quality degrade by using plasma. Plasma refers to matter showing collective behavior due to its ionized state, which is also called the fourth state of matter after solid, liquid, and gas. It is found naturally on earth as the flash seen when lightning strikes. In this research, naturally occurring plasma in the atmosphere has been produced in three different ways in the laboratory. The cold atmospheric pressure plasma produced in such a way has applications in a wide range of sectors for various purposes, including electronics, food safety, bio-medicine, agriculture, environment, and material science. With the global population growing and agricultural land diminishing, challenges like slow seed germination seedling growth, and crop loss intensify. Nepal is an agro-based economy and addressing agricultural issues is paramount. However, reliance on chemical fertilizers and pesticides harms the soil and environment. Research into cold atmospheric pressure plasma offers promising solutions. In any application involving plasma, the primary concern is ensuring the availability of plasma for the intended purposes. Plasma production requires a high-voltage power source as a prerequisite, after which applications can be explored. In this context, research into the production and application of cold atmospheric pressure plasma holds significant relevance, especially in addressing the aforementioned agricultural problems. Our study focuses on addressing problems for enhancing germination, seedling growth, and agricultural productivity and prolonging their freshness and bacterial decontamination of irrigated water by employing plasma directly and indirectly, to speed up seed germination, better seedling growth as well as improve yield, prolonging greenness and freshness of green leaves and remove contamination from water. Treating the water with plasma enriches the nutrients (such as nitrate/nitrite) in addition to bacterial decontamination caused by hydrogen peroxide. For plasma production, a fabricated power source made of readily available materials in the local market is capable of producing atmospheric pressure gliding arc discharge which is crucial for those institutions aiming to establish a plasma lab without high operating cost. Additionally, dielectric barrier discharge and plasma jet are produced using a commercially available power supply. The produced plasma is characterized using optical and electrical techniques, adhering to the classical relationship of electron excitation > vibrational > rotational temperature. These plasmas are applied to enhance agricultural production of cauliflower, potato, Basmati rice, and green leafy vegetables through direct (exposure directly on seeds) and/or indirect (exposure to water and then using this water for irrigation) approaches. The duration of plasma exposure significantly impacts several physico-chemical parameters of water, including the pH, electrical conductivity, total dissolved solids, oxidation-reduction potential, temperature, hydrogen peroxide, and the concentration of nitrite and nitrate. As activation time increases, the pH values of water decrease while other physico-chemical parameters increase synchronously. Wheat seed wettability increases and contact angle declines noticeably with a longer treatment time of plasma-activated water used for soaking seeds and direct exposure of plasma which is measured by wettability relation and a self-made prototype goniometer calibrated with a Ramé-Hart goniometer. Plasma-activated water accelerates the germination parameters of cauliflower (Brassica oleracea) compared to untreated crops. The seed’s wettability is significantly enhanced as the treatment duration increases in plasma-activated water. Basmati rice produces the highest level of seed germination, longer seedling shoots, and heavier plants using plasma-activated water. While for green leafy vegetables, it is observed that plasma-activated water, results in improved germination, production, and greenness. Similarly, the production of oyster mushrooms is beneficial by plasma-treated spawn. Direct plasma treatment also eliminates soluble bacteria like Scleropages aureus and Escherichia coli in water. Plasma-activated water reduces chlorophyll retention in detached Tejpat (Cinnamomum tamala) leaves compared to untreated water and accelerates the dormancy of potatoes. The detached Tejpat leaf could be preserved for longer times than normal water using plasma-activated water. The primary cause of these changes is the physical reaction of the plasma on the surface of the seeds and water, resulting in heat, shock waves, a strong electric field, and the presence of reactive oxygen and nitrogen species. These plasma applications demonstrate the potential of both direct and indirect methods to overcome declining agricultural production. Hence, cold atmospheric pressure plasma treatment enhances production, accelerates seed germination, retains chlorophyll in detached leaves, and sterilizes water for potential agricultural use. However, prolonged exposure to direct plasma and plasma-activated water can adversely affect agricultural commodities, necessitating optimization. As conventional fertilizers used in agriculture are not economically and environmentally friendly, plasma-based techniques offer a promising alternative for increasing agricultural production and establishing a more sustainable system in agricultural areas.Item Investigation of transport properties of site-substituted superstructures of complex oxides; (La,Sr)Toi3/(Ca,Y)Vo3(2023) Rai, Raj Kumar; Om Prakash NiraulaAvailable in fultextItem Factors influencing aviation visibility in Nepal(Institute of Science & Technology, 2024-01) Bhogendra Kathayat; Prof. Dr. Narayan Prasad ChapagainVisibility impairment in recent decades has become a serious challenge in the aviation sector of our region. This very issue has an adverse impact on comfort, air safety, and the overall aviation economy. Thus, quantification of the changes in atmospheric visibility and characterization of affecting factors at major airports is highly advantageous. Two major international airports in Nepal, Tribhuvan International Airport (TIA) at Kathmandu (KTM) and Gautam Buddha International Airport (GBIA) at Bhairahawa (BWA) were chosen as study sites. Over four decades of climatological data (1976–2022) supplemented with ground measurements, remote sensing data, reanalysis data, and satellite imagery were used. It was found that haze and fog are two major weather types reducing visibility in Nepal, both of which displayed a significant uptrend. At BWA, the fastest increase in haze is witnessed in the post-monsoon season (1.46% day/ year at 0.001 level of significance (α)); and winter fog is on the rise (1.05% day/ year, α = 0.001) too. A similar upward trend of winter haze frequency (2.36% day/year, α = 0.001) and fog frequency (0.46% day/year, at α = 0.05) in regime-I (1976–2000) in KTM was observed. Whereas, the trend of winter haze flattened to 0.36% day/year (at α = 0.05) and dense fog declined at the rate -1.28% per day per annum (at α = 0.01) in regime-II (2001–2022). By careful examination of all plausible climatological drivers of the change in KTM, strong evidence of decreasing humidity and increasing dew point depression after the year 2000 was found. A negative power function relationship between Aerosol Optical Depth (AOD) and visibility (VIS) at GBIA was seen. The relationship between PM2.5 and visibility (VIS) is similar. The best negative correlation between AOD and VIS occurred during monsoon (r = -0.66, p < 0.001) (r = -0.74, p < 0.001 between PM2.5 and VIS). The effect of aerosol water on VIS at GBIA was also seen, i.e., reduced airport visibility at increased RH. As a first effort to obtain sounding-based Planetary Boundary Layer Height (PBLH) climatology in Nepal, radiosonde measurements launched from a suburban site in KTM (November 2019–30 March 2022) were analyzed. It was observed that 91.20% of all early morning (0545 LT) soundings showed surface-based inversion, highlighting the existence of nocturnal Stable Boundary Layer (SBL) classification. Three different temperature-profile algorithms: Bulk Richardson method (RM) at a critical threshold〖 (Ri〗_(c )) of 0.22, Gradient of potential temperature method (〖GM〗_θ) and Surface Based Temperature inversion (SBI) method, were employed for estimating PBLH. Taking the SBI method as a benchmark method, we found that 〖 GM〗_θ yielded an almost unbiased estimate with a statistically significant coefficient (r = 0.99, p <0.001; 〖 R〗^2 = 0.99 and bias (∆H) = -3.57 m); RM slightly overestimated (r = 0.83, p < 0.001;〖 R〗^2= 0.65 and ∆H = 15.0 m); whereas ERA5 reanalysis PBLH measurements grossly underestimated (r = -0.22, 〖 R〗^2= -0.55 and ∆H = -100.94 m) stable PBL tops. The strongest and deepest surface inversions during winter and pre-monsoon months (PBLH ~ 200 ± 115 m in April) and the weakest and shallowest stable boundary layer in the early morning of monsoon (PBLH ~ 30 ± 11 m in September) were found. In the valley, PM 2.5 is higher in dry (the highest in March: 100 ± 13 μg m^(-3)) and lower in the wet season (the lowest in August: 8.6 ± 1.2 μg m^(-3)). Whereas, airport visibility at TIA is the best in wet (the highest in June: 6.6 ± 0.3 km) and worst during the dry season (the lowest in January: 3.9 ± 0.2 km). A positive correlation between PBLH and PM2.5 (r = 0.35, p < 0.001), good anti-correlation between VIS and PM2.5 (r = - 0.59, p < 0.001), and a poor-negative correlation between PBLH and VIS (r = - 0.16, p < 0.001) were found. The impact of the optical properties of aerosols (specifically PM2.5) and their hygroscopic effect on visibility in TIA was also studied. A sharp decline in visibility with an increase in the PM2.5 extinction coefficient and mass extinction efficiency (MEE) was observed. An exponential growth of hygroscopic growth factor (f (RH)) and a subsequent decrease in visibility with increased RH was noticed. It was observed that increased wind speed tends to improve visibility at the airport. Deterioration of airport visibility by the wind with a speed of 1–2 m/s flowing from the northeast through the south direction in the winter season was also noticed. Further, some of the salient microclimatic properties of winter fog at both of the airports were studied, too. Visibility at both airport sites displayed a definitive declining trend that was found to be linked with changes in air pollution emission and different meteorological factors. These changes pose serious adverse impacts on the aviation sector amongst many others. For the sustainable improvement of visibility, regionally coordinated efforts on implementation of strict air pollution-mitigation-measures are required. पर्यावरण, मानव-स्वस्थ, पर्यटन जस्ता मानव-सरोकारका बिबिध विषयहरु का अतिरिक्त उड्डयन क्षेत्रमा पनि वायुमण्डलिय-पारदर्शिता ( भिजिबिलिटी ) ले गम्भीर प्रत्यक्ष/ परोक्ष असर गर्न सक्ने निचोड बिगतका अनेकन् बैज्ञानिक अन्वेषणहरूको रहेको छ। विमानस्थलहरूमा वायुमण्डलिय-पारदर्शिता निर्धारित दुरी भन्दा कम हुन गएमा वायुयान उडान र अवतरणमा असहजता उत्पन्न हुँदा उडान तालिका प्रभावित भै यात्रुहरु लाई असुविधा हुने, उड्डयन संचालन खर्च बढ्ने देखि हवाई दुर्घटना सम्म हुन सक्ने जोखिम रहन्छ । हाम्रो देश, नेपालको उड्डयन सु-संचालनमा एक मुख्य भूमिका खेल्ने बिषय “वायुमण्डलिय-पारदर्शिता” लाई प्रभाव पार्न सक्ने सम्भावित मूल अवयवहरुको पहिचान गर्ने, तिनीहरुसंगको सम्बन्धको प्रक्रियागत अध्यन गर्ने, वायुमण्डलिय पारदर्शिताको ऐतिहासिक अवस्था र त्यसले उडान क्षेत्रमा पारेको प्रभावहरूको बैज्ञानिक अन्वेषण गर्ने मूल उदेश्य रहेको यस शोधका लागि नेपालका दुई मुख्य अन्तर्राष्ट्रिय विमानस्थलहरु—त्रिभुवन अन्तर्राष्ट्रिय विमानस्थल, काठमाडौँ र भर्खरै स्तरोन्नति गरिएको गौतम बुद्ध अन्तर्राष्ट्रिय विमानस्थल, भैरहवामा मापन गरिएको चार दशक भन्दा लामो अवधि (ईश्वी सम्बत १९७६–२०२२ ) को जलवायू तथ्यांकको प्रयोग र विश्लेषण गरिएको छ । साथमा लामो अवधि सम्म जमिनमा मापन गरिएका बायु प्रदुषणका तथ्यांक, जमिनमा रही वायुमण्डलको मौसमी/ पर्यावरण सूचकाङ्कमा मापन गर्ने उपकरणहरु (रिमोट-सेंसिंग उपकरण ) को प्रयोगबाट उपलब्ध तथ्यांक, पून-विश्लेषण गरि तयार पारिएका आँकडा (रि-एनालाइसिस्-डाटा) र भू-उपग्रहले संग्रह गरेका ऐतिहासिक तस्बिरहरुको बिस्तृत बैज्ञानिक अध्यन-विश्लेषण गरिएको छ । दुवै अध्ययन-स्थलमा मुख्यरुपमा तुवाँलो र हिउदें-हुस्सुका कारण वायुमण्डलिय-पारदर्शिता घट्ने गरेको यस अध्ययनले इंगित गरको छ । भैरहवा क्षेत्रमा अन्य मौसमको तुलना, मनसुनपछिको याम ((पोस्ट-मनसुन) (अक्टोबर, नोभेम्बर )) मा तुवाँलोले आकाश-ढाकिने-अवधि दर उच्च रहेको (१.४६% दिन प्रतिवर्ष ) र हिउदें-हुस्सुले आकाश-ढाकिने-अवधि दर बढ्दो (१.०५% दिन प्रतिवर्ष ) रहेको पाईएको छ । त्यसैगरी, ई. सं. १९७६–२००० को अवधिमा काठमाडौँ उपत्यकामा हिउँदे तुवाँलो तिब्र गति (२.३६% दिन प्रतिवर्ष) मा बढी तत्पश्चात उच्चतम बिन्दु आसपासमा रहेको र पछिल्लो अवधि (ई. सं. २०००–२०२२) काठमाडौँ विमानस्थलमा बाक्लो हुस्सुको आवृत्ति उल्लेखनीय रूपमा ह्रास (१.२८% दिन प्रतिवर्ष) भएको पाइयो । अध्यन गरिएका दुवै विमानस्थलहरू हरुको लामो समयको तथ्यांक विश्लेषण गर्दा, मूलतः बिबिध प्राकृतिक/ मानव सृजित बायु प्रदुषण उत्सर्जन श्रोतहरु बाट वायुमण्डलमा उत्सर्जन गरिएका अति सुक्ष्म बायु प्रदूषणका कण हरु (पीएम-२.५ (बायु गतिकिय ब्यास २.५ माइक्रो मिटर भन्दा कम भएका कण )) को वायुमण्डलमा एकाग्रता, तिनीहरु को प्रकार लगायतका बिबिध भौतिक तथा रासायनिक गुण हरुले वायुमण्डलको प्रकाशीय गुण र अन्त्यमा वायुमण्डलिय-पारदर्शिता निर्धारित हुने गरेको पाएको छौं । यसैगरि वायुमण्डलमा रहने जल बाष्प बढे संगै सल्फेट, नाइट्रेट, एमोनियम जस्ता जल बाष्प-संवेदनशील पीएम-२.५ समूह का प्रदूषणका सुक्ष्म कणहरुको आकार बढ्ने र अपवर्तक सूचकाङ्क (रिफ्र्याक्टिव इन्डेक्स ) घट्ने साथै पीएम-२.५ समूहका प्रदूषणका बिशेष सुक्ष्म कणहरुको सामुहिक-ह्रास-प्रगुणता (मास एक्सटिङ्गसन इफिशियंशी) बढ्ने कारणले वायुमण्डलको प्रकाशीय गुणमा बदलाब हुदै वायुमण्डलिय-पारदर्शितामा उल्लेख्य ह्रास आउने गरेको तथ्य पनि हाम्रो शोधले इंगित गर्दछ । यसैगरि, बायुमण्डल-आर्द्रता कम भएको बखत (सापेक्षिक आर्द्रता < ६०%) वायुमण्डलिय-पारदर्शिता बिशेष गरि पीएम-२.५ को एकाग्रतामा निर्भर रहने र आर्द्रता बढे संगै पीएम-२.५ को एकाग्रता संगको सम्बन्ध कमजोर हुने र आर्द्रताको प्रभाव प्रमुख हुने तथ्य देखिएको छ । वायुमण्डलिय-पारदर्शिता र अति सुक्ष्म बायु प्रदूषणका कणहरुको एकाग्रता बीच विपरीतार्थक सम्बन्ध रहने र भैरहवा विमानस्थलमा ति दुई बीचको सहसम्बन्ध ( को-रिलेशन ) वर्षात याम (मनसुन (जून, जुलाई, अगस्त, सेप्टेम्बर)) मा उत्कृष्ट (पिअर्शन सहसम्बन्ध गुणक = -०.७४ ) रहेको पाइयो । यस्तै, काठमाडौँ उपत्यका माथिको आकाशको माथिल्लो सतह सम्म को मौसमी अवस्था बारेमा जानकारी लिन र मौसमी पूर्व-अनुमानमा मद्दतका लागि प्रत्येक बिहानी प्रक्षेपण गरिने बिबिध मौसमी विवरण मापन गर्ने उपकरण बोक्ने बेलुन (रेडियो-सन्ड) द्वारा मापन गरिएको लगभग तिन साल (ई. सं. २०१९–२०२२) को तथ्यांक को विश्लेषण गरि वायुमण्डलिय-सिमा-तह (बाउन्ड्री लेयर) पत्ता लगाउने बिबिध जटिल उपायहरु मध्ये तीनवटा तरिका हरुको निर्क्योल र प्रमाणिकरण गर्नु यस शोधको एक मुख्य उपलब्धि रहेको छ । बिहानीपख को काठमाडौँ उपत्यकाको बायुमण्डलीय-सिमा-तह सामान्यतः स्थिर प्रकृतिको रही बायु प्रदुषणका सुक्ष्म कणहरु लाई सिमा-तह भित्रै संकुचित राख्ने भएकोले बिहानी पखको वायुमण्डलिय-पारदर्शिता न्युन रहने गरेको पुष्टि हाम्रो उपरोक्त खोजले गरको छ । यसैगरि, काठमाडौँ उपत्यकामा बायुको गतिको घटबढ संगै बायु प्रदुषणका सुक्ष्म कणहरुको उपलब्धता/ एकाग्रतामा फरक पर्ने कारणले विमानस्थलको वायुमण्डलिय-पारदर्शिता फरक पर्न जाने साथै हिउँद महिनाहरूमा बिशेष गरि पूर्व दिशाबाट विमानस्थलको आकाशमा प्रवेश गर्ने प्रदुषित बायुका कारण विमानस्थलको वायुमण्डलिय-पारदर्शिता घट्ने गरेको पनि पाइयो । दुवै विमानस्थलहरू को वायुमण्डलिय-पारदर्शितामा बिगतका दशकहरुमा देखिएको सामयिक परिवर्तनको सम्बन्ध विशेषगरि बढ्दो बायु प्रदुषण, वायुमण्डलमा मौजुद जल बाष्प र हावाको गति जस्ता जलवायुमा आएका परिवर्तनसंग रहेको तथ्य हाम्रो शोधको निचोड रहेको छ । यस अलावा, हिउँद महिनाहरूमा दुवै विमानस्थलहरूको बिमान उडान-अवतरण सु-संचालनमा गम्भीर प्रभाव पार्ने हिउँदे-हुस्सु लाग्न शुरु-हुने र अन्त्य-हुन-सक्ने सम्भावित समय, र हुस्सुले आकाश ढाकि रहने सम्भावित अवधि पत्ता लगाएर उड्डयन क्षेत्र र मौसम पूर्व अनुमानमा सहयोगको प्रयास गरेका छौं । वायुमण्डलिय-पारदर्शिताको सामयिक परिवर्तनले दुवै विमानस्थलहरूमा कसरी असर गरिरहेको छ भन्ने प्रश्नको उत्तर खोज्ने प्रयास पनि यस शोधको रहेको छ । अन्त्यमा, घट्दो वायुमण्डलिय-पारदर्शिता र सो संग सम्बन्धित जोखिमहरुको न्यूनीकरणका हेतु बिबिध सुझाब पनि पेश गरेका छौं ।Item Study of Kinematics and Chemical abundances properties of Damped and Sub-Damped Lyman alpha absorbers from the Sloan Digital Sky Survey(Institute of Science & Technology, 2024-06) Singh Maharjan, Yogesh; Dr. Niraj DhitalStudying the lifecycle of metals and gas in a galaxy is important to understand the formation and development of Galaxies. Galaxies at high redshifts are very faint to study in emission-line technique, but can be observed in absorption. Generally, background quasars are utilized to study the galaxies in the foreground. Quasar absorption lines serve as valuable tools for studying features of gas within and surrounding galaxies. These lines are independent of quasar luminosity and have been widely employed in the study of galaxies, IGM and CGM. However, getting the high- resolution spectroscopic observation of quasars is very expensive, meanwhile, low resolution data from the all-sky survey such as SDSS are publicly available. For this research, we utilize hundreds of spectra from the SDSS with galaxies of high-redshift to identify, study the kinematic and chemical properties of the gas-rich galaxies (Damped Lyman-alpha systems). The report introduces measurements chemical abundance of DLAs and sub-DLAs quasar absorbers galaxy evolution traced by at cosmological redshift of 3 ≲ zabs ≲ 5. We found 3 new DLAs with neutral hydrogen column densities log NH I (cm−2) = 20.55 ± 0.2, 20.34 ± 0.2, 20.35 ± 0.2 and 3 new sub-DLAs with neutral hydrogen column densities log NH I (cm−2) = 20.1± 0.2, 20.25 ± 0.2, 20.1 ± 0.2 with multiple ions detected at more than 3 σ. These 6 new gas-rich galaxies show strong Lyman α absorption in the background Quasars with 2 sightlines probing metal rich and remining 4 probing metal poor galaxies. We determined H I column density using Voigt profile fitting program VoigtFit. We further estimate the equivalent widths and metal column densities fitting the Gaussian and applying the Apparent Optical Depth (AOD) method with the help of spectra analysis tool called Linetools. We further studied the relative abundance of [C/O] and [Si/O] and found that two out of six systems have solar and other have super-solar ratios which may signify the enrichment from early stars. We also measure the velocity dispersion to study the kinematics. We also detect C IV and Si IV absorption signifying that the collisional ionization may be prevalent in these DLAs/sub-DLAs. The column density ratios of N (C IV)/N (Si IV) in the range of in the range of 1.4 – 6.5, signifying these absorbers may be ionized by both the photoionization and collisional ionization.Item Investigation of Novel Topological Properties in Kagome Metals A2t3s4 (Where A are K, Rb & Cs and T are 3d & 4d Transition Metals(Institute of Science & Technology, T. U., 2024-07) Acharya, Gang Bahadur; Dr. Madhav Prasad GhimireThere has been significant research interest in topological materials in recent years due to their demonstration of fundamentally novel physical phenomena. A distinguishing feature of topological materials is the presence of protected surface states without energy gaps, a characteristic that emerges from the nontrivial topology of bulk wave functions. These materials could create novel quantum information technology devices and applications. Kagome lattice crystal structures are promising for exploring topological properties, including features such as Dirac, Weyl, and Nodal line characteristics in topological semimetals. The electronic structure of a kagome lattice inherently includes Dirac fermions, flat bands, and van Hove singularities. Over the past decade, the topological Weyl semimetals (WSMs) have experienced an increase in popularity in research, leading to precise theoretical predictions, controlled material synthesis, and advanced characterization techniques. These techniques include angle-resolved photoemission spectroscopy, scanning tunneling microscopy, magnetotransport measurements, and optical spectroscopy. In this thesis, we used density functional theory (DFT) simulations to investigate a series of proposed compounds’ electronic, optical, magnetic, and topological properties. Initially, we examined the electronic, magnetic, and topological properties of the gapless systems Cs2Co3S4 and Li2Fe3S4. Regarding topological features, we were especially interested in exploring Weyl semimetallic characteristics and related properties, including Berry curvature, anomalous Hall conductivity, and Fermi arc surface states. We found Cs2Co3S4 to be a ferrimagnetic half-metal with a total spin magnetic moment of about 3 𝜇B per formula unit. It shows an energy band gap of 0.36 eV in the majority-spin channel and a pseudo-gap at the Fermi level in the minority spin channel. We identified several sets of low-energy Weyl points and traced their dependence on the direction of magnetization. The intrinsic anomalous Hall conductivity is predicted to reach a magnitude of 500 Ω−1cm−1, comparable to values obtained in other celebrated Weyl semimetals. In addition, we calculate the Fermi arc surface states that connect the Weyl points with opposing chirality. Li2Fe3S4 also has Weyl semimetallic characteristics with lowenergyWeyl points near the Fermi level. For gapped systems, we found that Rb2Ni3S4, Cs2Ni3S4, Rb2Pd3S4, and Cs2Pd3S4 exhibit nonmagnetic ground state. Ni and Pd atoms constitute a kagome lattice in a two-dimensional plane. These materials possess a semiconducting nature. Interestingly, a flat band was noticed below the Fermi level, demonstrating one significant feature of the kagome lattice. Conversely, K2Mn3S4 and Rb2Mn3S4 display a magnetic ground state while maintaining a similar semiconducting character. In the case of materials with a kagome structure, we conducted further studies on their optical properties, revealing optical activity in both the visible and lower ultraviolet energy ranges. Based on these findings, gapless topological Weyl semimetals may be suitable for use in high-mobility devices, spintronics, and quantum computing. Kagome-gapped materials, on the other hand, may be possible for optoelectronic device applications. cfwf/e"t ?kn] lgs} gofF / ljlzi6 u'0fx¿ k|bz{g u/]sfn] xfnsf s]xL ;dodf topological material x¿sf] cg';Gwfgdf dxTjk"0f{ cle?lr b]vfk/]sf] 5 . lagf s'g} energy gap o:tf kbfy{x¿sf] ljlzi6 u'0f;+/lIft surface states sf] pkl:ylt non-trivial topology sf] bulk wave functions af6 k|s6 x'G5 . oL material x¿ cgf}7f] quantum ;"rgf k|ljlwsf pks/0f ;[hgf tyf pkof]u ug{sf nflu k|of]u ul/G5g\ . Topological semimetal df Dirac, Weyl / nodal line ;lxtsf] ljz]iftfx¿sf] cGj]if0f ug{ kagome lattice crystal ;+/rgf ;DefAo pDd]bjf/ xf] . Kagome lattice sf] electronic :j?k leq :jfefljs ?kn] Dirac fermions, flat bands / van Hove singularities cfpF5g\ . ljutsf bzsdf topological Weyl semimetals If]qsf] nf]slk|otf ;l6s ;}4flGts eljiojf0fL, lgolGqt material ;+Zn]if0f tyf pGgt characterization k|ljlwx¿ ;lxtsf] cg';Gwfg sfo{df a9]sf] 5 . o;leq angle-resolved photoemission spectroscopy, scanning tunneling microscopy, magneto-transport dfkg, optical spectroscopy tyf cGo kb{5g\ . of] y]l;;df xfdLn] k|:tfljt of}lussf] electronic, optical, magnetic / topological u'0fx¿sf] cg';Gwfg density functional theory (DFT) k|of]u u/L u/]sf 5f}F . z'?df, Cs2Co3S4 / Li3Fe3S4 gapless system x¿sf] electronic, magnetic / topological lu'0fx¿ hfFr ul/of] . Topological ljz]iftfx¿sf] ;Gbe{df, vf;u/L Weyl semimetallic / To;Fu ;DalGwt ljz]iftfx¿ h:t} Berry curvature, anomalous Hall conductivity / Fermi arc surface df xfd|f] ?lr lyof] . xfdLn] Cs2Co3S4 df sl/a 3μ_B k|lt formula o"lg6 total spin magnetic moment ;lxt half-metallic ferrimagnetism /x]sf] kfof}F . o;n] majority spin channel sf] Fermi level df 0.36 eV sf] energy band gap / minority spin channel df pseudo-gap b]vfpFb5 . xfdLn] low-energy Weyl points sf w]/} ;d"xx¿sf] klxrfg uof}F / ltgLx¿sf] r'DasLs/0fsf] lbzfsf] lge{/tf kQf nufof}F . Intrinsic anomalous Hall conductivity clwstd 500 Ω-1cm-1 k'u]sf] kfOof] h'g rflxF k|l;4 Weyl semimetal x¿sf] value ;Fu t'ngfof]Uo 5 . o;sf cltl/St xfdLn] Fermi arc surface states h'g ljk/Lt chirality ;lxtsf Weyl points nfO{ hf]8\b5g\, To;sf] klg vf]hL uof}F . Li3Fe3S4 df klg Weyl semi-metallic u'0fx¿ 5g\ h:df Fermi level sf] glhs low-energy Weyl point x? k|fKt eP . Gapped system x¿df xfdLn] Rb2Ni3S4, Cs2Ni3S4, Rb2Pd3S4 / Cs2Pd3S4 n] non-magnetic -u}/r'DasLo_ ground state k|bz{g u/]sf] kfof}F . Ni / Pd k/df0f'x¿n] two-dimensional plane df kagome lattice lgdf{0f ub{5g\ / semi-conducting u'0f wf/0f ub{5g\ . rfvnfUbf] t s] 5 eg], oL of}lusx¿df Fermi level sf] tn flat band b]lvof] h;n] kagome lattice sf] Ps dxTjk"0f{ nIf0f bzf{pFb5 . o;sf] ljk/Lt K2Mn3S4 / Rb2Mn3S4 n] semi-conducting u'0f sfod ub}{ magnetic ground state k|bz{g ub{5g\ . xfdLn] kagome ;+/rgf ePsf material x¿df ltgLx¿sf] optical u'0fsf] yk cWoog uof}F h;n] visible / lower UV energy bfo/f optical ultljlwsf] k'li6 eof] . oL pk/f]St kl/0ffdx¿sf] cfwf/df high mobility pks/0fx¿, spintronics / quantum computing sf] nflu gapless topological Weyl semimetal x¿ pko'St x'G5g\ eGg] lgisif{ lgsfNg ;lsG5 . ;fy}, kagome gapped materials rflxF optoelectronic pks/0fx/sf] nflu pko'St / cfbz{ x'G5g\ eGg] klg lgisif{ lgsfNg ;lsG5 .Item First-principles study of structural, electronic and magnetic properties of defected (monovacant) hexagonal boron nitride sheet(Department of Physics, 2021) Khatri, KisanThe first-principles calculations based GGA functionals was implemented to study the structural, electronic and magnetic properties of pure and defected hexagonal boron nitride (h-BN) monolayer sheet using Quantum ESPRESSO (QE) package, 6.5 version. The pure h-BN is found to be non-magnetic insulator with band gap of 4.64 eV. The calculated values of formation energy reveals the structural stability of defected system. The formation energies for B and N vacant system are found to be 16.45 eV and 12.84 eV respectively which predicts that N vacant system is more preferable with lower formation energy. The defect on a system abruptly changes the electronic and magnetic properties of h-BN system. The 6.25 % B-vacancy and 6.25 % N-Vacancy defects are found to be half metallic ferromagnet with total magnetization of 2.74 /cell and magnetic semiconductor with total magnetization 1.00 B /cell respectively. BItem Investigation of Transport Properties of Sitesubstituted Superstructures of Complex Transition Metal Oxides: (La,Sr)TiO3/(Ca,Y)VO3(Institute of Science & Technology, 2023-11) Rai, Raj KumarTo unravel the structural, chemical and mechanical stabilities, electronic, thermoelectric, and optically driven transport properties of pristine and site-substituted complex transition metal oxides (titanates and vanadates), we have employed the density functional theory (DFT) and the dynamical mean field theory (DMFT) approach. The continuous time quantum Monte-Carlo (CT-QMC) with hybridization expansion technique is used as impurity solver of DMFT and the maximum entropy model (MEM) is employed for analytic continuation (AC). The study also investigates the metal insulator phase transition (MIT) of the strongly correlated electronic materials by analyzing the variation of spectral density with onsite Coulomb interaction (U) and thermodynamic parameter (β). Here, the structural, chemical, and mechanical properties of vanadates: (La1−x SrxVO 3 )n,(Ca1−xSrxVO3) n and (La1−xCaxVO3)n , and titanates: (La1−x CaxTiO3)n, (La1−x SrxTiO 3)n and (Ca1−xYx TiO 3)n systems studied using the first-principles based calculations. The energy minimization curves, and negative values of cohesive energy (CE) and formation energy (FE) reveal their higher structural and chemical stabilities, indicating that these pristines and the site-substituted vanadates and titanates are chemically stable and viable for laboratory synthesis. The modulus of elasticities, Poisson’s and Pugh’s ratios, anisotropy factor, and Cauchy pressure of the systems indicate their mechanical stabilities and the results suggest that superstructures are elastically weaker than pristine systems. The DFT calculation shows the pristine CaVO3, SrVO3, LaVO3, LaTiO3,YTiO 3 , YVO 3and all the superstructures are metallic/semiconducting in nature which contradicts the experimental information, whereas resembles with other theoretical calculations. The pristine SrTiO3 and CaTiO3 found to be band insulators with band gaps 3.42 eV and 2.76 eV respectively, which resembles closely to other available information. For the realistic picture of electronic structures, DMFT approach (CT-QMC data) along with MEM are employed and found that MIT parameters for pristines and superstructures of vanadate systems are mentioned in the parentheses, CaVO3 (U = 5.0 eV, β = 6.0 (eV)−1), LaVO3 (U = 4.5 eV, β = 8.0 (eV)−1), SrVO3 (U = 2.5 eV, β = 6.0 (eV)−1 ), LaSrV2O6 (U = 4.0 eV, β = 10.0 (eV)−1 ) and La0.40Ca0.60VO3 (U = 5.0 eV, β = 10.0 viii(eV)−1), respectively. Similarly, the DMFT results of pristines and superstructures of titanate systems are also computed (mentioned in the parentheses) as, LaTiO3 (U = 4.0 eV, β = 8.0 (eV)−1), YTiO3 (U = 5.0 eV, β = 10.0 (eV)−1), LaSrTi2O6 (U = 4.7 eV, β = 6.0 (eV)−1 ), La 0.8 Sr 0.2TiO 3 (U = 3.2 eV, β = 10.0 (eV)−1 ) and Ca x Y1−xTiO 3 (U = 5.0 eV, β = 7.0 (eV)−1), respectively, and found to be consistent with other results. The analysis of characteristic sharp quasi-particle peaks reveal that vanadate, La0.40 Sr0.60VO3and titanate, La0.80Sr0.20TiO3 superstructures show metallic phases in same set of MIT parameters, (U = 3.0 eV, β = 6.0 (eV)−1 ). The set of Mott quantum critical point (QCP) for La 0.40 Ca 0.60 VO 3 system is observed for an elevated temperatures at (UC = 2.95 eV, βC = 23.58 (eV)−1). The clear Mott gaps for La0.40 Ca0.60VO 3 , and La 0.80 Sr 0.20 TiO 3 are computed as 0.73 eV (U = 5.0 eV, β =10.0 (eV)−1) and 0.74 eV (U = 3.2 eV, β =10.0 (eV)−1), respectively. The BoltzTraP calculations show that La0.40 Ca0.60VO3 and La0.80Sr0.20TiO3 systems have peak values of electrical conductivities (2.11 × 1020 (Ω.m.s)−1 , 3.75 × 1020 (Ω.m.s)−1 ), and thermal conductivities (1.54 × 1015 W/(m.K.s) and 2.68 × 1015 W/(m.K.s) ), respectively, at room temperature (300 K) for a given chemical potential (μ = −0.14eV ) . Both have the larger Seebeck coefficient (S), and thermoelectric power factor (TPF) indicating that these superstructures are better candidate for thermoelectric applications. The study of Seebeck coefficient and Hall coefficient reveal that the thermoelectric phase transition occur due to the site-substitutions of the superstructures. The photo-induced behaviors of materials in IR-to-UV regions, including visible region are investigated using the dielectric function, index of refraction, ELOSS function, absorptivity, reflectivity, optical conductivity and sumrule. The Drude peaks result support the model parameters (U and β) of DMFT calculation for the optically driven MIT in La0.40Sr0.60VO3 and La0.80Sr0.20 TiO3 superstructure systems. Finally, the study of the MIT model parameters and diverse phase diagrams help us to fabricate these materials to design Mottronic devices (neuromorphic computing, quantum computing, resistive memory devices and artificial neurons), and energy harvesting devices (photovoltaics, solar and radioisotope thermoelectric generators and freezers). यस अनुसन्धान कार्यमा जटिल प्रकृतिका ट्रान्जिसन धातुहरुको अक्साईड र तिनीहरुको सुपर संरचनाहरुको संरचनात्मक, रसायनिक र यान्त्रीक स्थायीत्व तथा ईलेक्ट्रोनिक, तापजन्यविद्युतीय र प्रकाश-प्रेरित परिवहन (ट्रान्सपोर्ट) को प्रकृति एवं चालक-अचालकताको अवस्था-संक्रमण (MIT) सम्बन्धित मोडेल प्यारामिटरहरुको विषयमा डेन्सिटी फङ्सनल सिद्धान्त (DFT) र डाईनामिकल मीन फिल्ड सिद्धान्त (DMFT) अन्तर्गतको कन्टिन्युअस टाईम क्वान्टम मोंटे कार्लो (CT- QMC) मध्ये हाईब्रिडाईजेशन विस्तार एल्गोरिदम उपयोग गरी विभिन्न भ्यानेडेट्स: [(Ca1-xSrxVO3)n, (La1-xSrxVO3)n र (La1-xCaxVO3)n] तथा टाइटानेट्स: [(Ca1-xYxTiO3)n, (La1-xSrxTiO3)n र (La1-xCaxTiO3)n] पदार्थहरुको विस्तृत अध्ययन तथा अन्वेशण गरिएको छ । उर्जा न्यूनिकरण कर्भहरु, कोहेसिभ र फर्मेसन उर्जाहरुको ऋणात्मक मानको आधारमा ति भ्यानेडेट र टाइटानेटहरुको आधारभुत संरचना र सुपर–संरचनाहरुको संरचनात्मक र रसायनिक स्थायीत्व रहेको साथै तिनीहरुलाई प्रयोगशालामा संस्लेषण र निर्माण गरी जीवनोपयोगी प्रयोगमा ल्याउन समेत सकिने निस्कर्ष निकालिएको छ । यसै गरी विभिन्न मेकानिकल प्यारामिटर जस्तै ईलास्टिक कन्सट्यान्ट, ईलास्टिक मोड्युलस, पोइसन तथा पगका अनुपातहरु, काउची दबाब र एनाइसोट्रपिक फ्याक्टरहरुका मानहरुको आधारमा, सम्पूर्ण अध्ययन गरिएका संरचनाहरुले यान्त्रिक स्थायीत्वको प्रत्याभूति गर्दछन् । यि अध्ययनहरुले साइट-प्रतिस्थापित सुपर संरचनाका ईलास्टिक गुणहरु तुलनात्मक रुपले आधारभूत संरचनाहरु भन्दा न्युन देखिएका छन् तथापी तिनीहरुको उपयोग विभिन्न स्मार्ट अनुप्रयोगहरुमा हुन सक्दछन्, जस्तै मोट्रोनिक अनुप्रयोगहरु (न्युरोमोर्फिक कम्प्युटिङ्ग, क्वान्टम कम्प्युटिङ्ग, रजिस्टीभ मेमोरी, कृत्रिम न्यूरोन) तथा उर्जा संकलन अनुप्रयोगहरु (फोटो भोल्टाइक, सौर्य तथा रेडियो आइसोटोपीक तापजन्यविद्युतीय जेनेरेटरहरु, फ्रिजर)को प्रयोजनका लागि सदुपयोग गर्न सकिने निस्कर्ष निकालिएको छ। यहाँ DFT को अध्ययनको आधारमा, केही आधारभूत संरचनाहरु (CaVO3, LaVO3, SrVO3, YVO3, CaTiO3, LaTiO3, SrTiO3, YTiO3)का प्राप्त तथ्याङ्कहरु प्रयोगात्मक अध्ययनको तथ्याङ्कहरुसँग भन्दा सैद्धान्तिक अध्ययनसँग हाम्रो निस्कर्षहरु सहमत देखिन्छन् । हाम्रो गणनाले CaTiO3 र SrTiO3 हरुको व्याण्ड ग्याप क्रमशः 2.76 eV र 3.42 eV सहित व्याण्ड अचालकका गुण देखाउछन् । यसरी नै CaVO3, SrVO3 र YVO3 हरु चाहीं सह-सम्बन्धित चालक गुण देखाउँछन् भने LaVO3, LaTiO3, र YTiO3 चाहीं मोट-अचालकहरु देखिन्छन् । विशेषत: साइट-प्रतिस्थापित सुपर-संरचनाहरु चाहीं सह-सम्बन्धित चालक वा अर्ध-चालक गुण देखाउँछन् । i यसै गरी हामीले DFT तथ्याङ्कहरुको प्रयोगगरी DMFT सहित म्याक्सिमम इन्ट्रोपी मोडल (MEM) को उपयोग गर्दै मोट ग्याप प्यारामिटरहरु विभिन्न आधारभूत संरचनाहरु र तिनीहरुको साइट-प्रतिस्थापित सुपर-संरचनाहरु मध्ये भ्यानेडेट प्रणाली, CaVO3 (U =5.0 eV, β=6.0(eV)^(-1)), LaVO3 (U = 4.5 eV, β=8.0(eV)^(-1)), SrVO3 (U=2.5eV, β=6.0(eV)^(-1)), La0.50Sr0.50VO3 (U = 4.0 eV, β=10.0(eV)^(-1)) / La0.40Ca0.60VO3 (U = 5.0 eV, β=10.0(eV)^(-1)) साथै टाइटानेट प्रणाली, LaTiO3 (U =4.0 eV, β=8.0(eV)^(-1)), YTiO3 (U = 5.0 eV, β=10.0(eV)^(-1)), Ca0.33SrY0.67TiO3 (U = 5.0 eV, β=7.0(eV)^(-1)) / La0.80Sr0.20TiO3 (U = 3.2 eV, β=10.0(eV)^(-1))हरुका MIT मोडेल प्यारामिटरहरु कोष्ठमा उल्लेखीत भए बमोजिम गणना गरिएका छन् । हाम्रा साइट-प्रतिस्थापित सुपर-संरचना मध्ये La040Ca0.60VO3 र La0.80Sr0.20TiO3 प्रणालीहरुको मोट ग्यापहरु क्रमशः 0.73 eV (U = 5.0 eV, β=10.0(eV)^(-1)) र 0.74 eV (U = 3.2 eV, β=10.0(eV)^(-1)) प्राप्त भएका छन् । त्यसरी नै ति दुवै प्रणालीहरुको क्वाजाई पार्टीकल सूचालकता चाहीं एकै मोडेल प्यारामिटरको सेट (U = 3.0 eV, β=6.0(eV)^(-1)) मा देखिएको छ । अर्कोतर्फ La0.40Ca0.60VO3 प्रणाली संवद्ध एक उच्च तापमानको क्वान्टम क्रिटिकल बिन्दु (QCP) को मोडेल प्यारामिटर (UC = 2.95 eV, β_C=23.58(eV)^(-1)) देखिएकोछ । यसरी नै बोल्ट्ज ट्रयाप एल्गोरिद्मको उपयोगगरी गणना गरिएको विद्युतीय चालकता, तापजन्य चालकता, सि-वेक गुणाङ्क तथा तापजन्यविद्युतीय पावर फ्याक्टर (TPF) को आधारमा उल्लेखित सुपर-संरचनाहरु तापजन्यविद्युतीय अनुप्रयोगका लागि उपयोग गर्न सकिने प्रबल संभावना देखिएको छ । यस खोजकार्यमा प्रकाश-प्रेरित परिवहन सम्बन्धी अध्ययनको लागि IR - UV (0 – 20.0eV) रेन्जको फोटोन उर्जा प्रयोग गरी डाईलेक्ट्रिक फङ्सन, अपवर्तक सूचकांक, ELOSS फङ्सन, अवशोषण, परावर्तन, समरुल तथा प्रकाशजन्य चालकताहरुको अध्ययनबाट उपरोक्त पदार्थहरु प्रकाश-प्रेरित उपकरण तथा परिवहन कार्यमा उपयोग हुन सक्ने निस्कर्ष प्रस्तुत गरिएको छ ।Item ADSORPTIONOFHCNANDH2S OVERZnOANDAl-DOPEDZnO MONOLAYER:FIRSTPRINCIPLES STUDY(Amrit Campus, 2024-02-25) Oli, DipakThe adsorption of 𝐻𝐶𝑁 and 𝐻2𝑆 molecules in 3× 3× 1 monolayer and 𝐴𝑙- doped 𝑍𝑛𝑂, replacing one 𝑍𝑛-atom by 𝐴𝑙-atom was studied in spin-polarized DFT by applying the Vienna Abinitio Simulation Package (VASP). Various exchange-correlation functionals like GGA-PBE,metaGGA-SCAN,andDFT+UusingabasissetnamelyPAW(Projected Augmented Wave) pseudopotential were employed in order to determine the structural, electronic, and magnetic properties of the pristine and 𝐴𝑙- doped ZnO before and after the adsorption of 𝐻𝐶𝑁 and 𝐻2𝑆. ZnO monolayer and the ZnO adsorbed with 𝐻𝐶𝑁 and 𝐻2𝑆 were found to be non-magnetic whereas Al-doped ZnO upon the adsorption of 𝐻𝐶𝑁 and 𝐻2𝑆 was found to be magnetic in nature. Similarly, the lattice parameters of ZnO were found to be increasing with the presence of foreign elements. The outcome thus achieved is nearly identical and in good agreement with the earlier theoretical investigations.Item COMPARATIVEANALYSISOFAEROSOL ÅNGSTRÖMEXPONENTVARIATIONIN POKHARA:ACASESTUDYCOMPARINGKANPUR ANDBEIJINGFORTHEYEARS2019AND2020(Amrit Campus, 2024-02-25) Pokhrel, SunilThis thesis presents a collection of AOD data from AERONET followed by calculation and comparative analysis of the Ångström Exponent (𝛼) variation in Pokhara (28.21°N, 83.96°E), Nepal, with Kanpur(26.45°N and 80.33°E), India, and Beijing (39.90°N, 116.41°E), China, for the years 2019 and 2020. The study utilizes mathematical analysis to examine the fluctuations in 𝛼 values observed in these cities and investigates their implications for air pollution dynamics. The maximum and minimum 𝛼 values are calculated to be Pokhara (1.73 & 0.60); Kanpur (1.76 & 0.15) and Beijing (1.65 & 0.13) in the year 2019 and similarly, Pokhara (1.67 & 0.17); Kanpur(1.73 & 0.21) and Beijing(1.65 & 0.16) in the year 2020, providing insights into the seasonal and temporal variations of aerosols. The study explains the trimester-wise analysis of the variation of 𝛼 in Pokhara with the comparison of two calendar years 2019 and 2020. This further delves into the seasonal patterns of 𝛼, shedding light on the influence of specific factors during different periods. The research also explores that 𝛼 does not only depend upon the seasons and weather but also on meteorological parameters, pollutant emissions, atmospheric conditions, and other multidimensional particles dissolved in the atmosphere, however, the trend can be analyzed and compared. The analysis finally can be inferred that in Pokhara, the aerosol loading and water deposition in the atmosphere , is barely affected by anthropogenic sources. The findings underscore the significance of understanding and addressing air pollution challenges in these regions. This study contributes to the scientific understanding of 𝛼 variations and offers valuable insights for policymakers and researchers working towards sustainable air quality management.Item Study on the characteristic emission loading from the public transport and its contribution for air quality degradation over the Kathmandu valley : Grided emission estimation and dispersion modeling(Department of physics, 2021) Shrestha, ChiranjibiThe Kathmandu valley is witnessing an extremely poor air quality from years. The degradation of air quality over Kathmandu is often found to be associated with the spontaneous urbanization, haphazard industrial expansions and vehicular fleet. Present study was conceived to understand the contribution of transport sector in degrading the air quality of Kathmandu valley. We developed a comprehensive gridded emission inventories of potential pollutants and performed particulate pollutant dispersion modelling using a comprehensive Chemical Transport Modelling (CTM) at the horizontal grid resolution of 1 km 2 over an area of 70 km x 70 km that covers the Kathmandu valley and its immediate surroundings, initialized with the Weather Research and Forecasting (WRF) simulated meteorological fields. The gridded emission inventory showed about 1918.17 kg km −2 of TSP, 12872.74 kg km −2 of CO, 6925.82 kg km −2 of NOx and 708.41 kg km −2 of SO2 are currently loaded into the atmosphere of the valley per day from the public transport over the Kathmandu valley. CTM simulation shows the ambient concentration of PM2.5 due to public transport fleets appears a minimum during the day time and remains maximum during the night and morning times. The pollutants released over the valley are transported to the east and are flushed out into the eastern neighbouring valley. The contribution of the public transport fleet to the deterioration of ambient air quality of the valley appears significant compared to total emission from transport sector.Item Structural and Spectroscopic Studies on Cefalexin ond Methyldopa Using Quantum Mechanical Methods(Institute of Science & Technology, 2024-01) Chaudhary, TarunThe spectroscopic characteristics, conformational stability, electronic and biological activity of cefalexin and methyldopa have been investigated using quantum mechanical techniques. The density functional theory (DFT) at the B3LYP/ 6-311++G(d,p) level was utilized to optimize the molecules and explore their vibrational properties. The intramolecular and intermolecular hydrogen bonding in cephalexin has been discussed in terms of IR and Raman spectra. Additionally, the quantum theory of atoms in molecules (QTAIM) was used to predict the nature of hydrogen bonds. Similarly, determining vibrational properties, the presence of hydrogen bond interactions in methyldopa has been scrutinized more precisely, using QTAIM and the reduced density gradient (RDG) in monomer and dimer form. On the basis of electron localization function (ELF), the electron localized region and the delocalized region have been depicted. The Molecular electrostatic potential (MEP) has been used to describe the charge distribution around the molecules. From the MEP map, the electrophilic and nucleophilic sites were anticipated. The energy of the lowest unoccupied molecular orbital (ELUMO), the highest occupied molecular orbital energy, (EHOMO), and their energy gap (∆E) have been used to examine the chemical stability of the molecules. Furthermore, the nature of chemical reactivity, the energy gap, global, and local reactivity characteristics were established. Natural bond orbital (NBO) analysis was carried out to determine the stabilization energy due to charge delocalization between the bonding and antibonding. The relation of standard thermodynamic parameters like heat capacity, enthalpy and entropy with temperature has been studied. Ultimately, a molecular docking simulation has been performed to study the biological activities of the molecules. The binding activity of cefalexin with the protein matrix carbonic anhydrase II and leukotriene A-4 hydro lase was predicted from molecular docking approach. Similarly, the binding activity of ligand methyldopa with protein Lysine-specific demethylase 4D-like was performed. सेफेलेक्सिन र मेथाइलडोपाका स्पेक्ट्रोस्कोपिक स्वरुपहरु, संरचनात्मक स्थिरता, इलेक्ट्रोनिक र जैविक गतिविधि, क्वान्टम मेकानिकल विधि प्रयोग गरेर अनुसन्धान गरिएको छ। अणुहरूलाई अप्टिमाइज गर्न र तिनीहरूको भाइब्रेशनल गुणहरु अन्वेषण गर्न B3LYP/6-311++G(d,p)/Density Functional Theory (DFT) प्रयोग गरिएको थियो। सेफेलेक्सिनको IR र Raman स्पेक्ट्राका आधारमा इन्ट्रामोलिक्युलर र इन्टरमोलिक्युलर हाइड्रोजन बन्डको व्याख्या गरिएकोछ। । साथै, क्वान्टम थ्योरि अफ एटम्स इन मोलिकुल्स (QTAIM) विधि प्रयोग गरि हाइड्रोजन बन्डको प्रकृतिको बारे प्रस्तुत गरिएकोछ। त्यसै गरी, मेथाइलडोपाको मोनोमर र डाइमर संरचनाका भाइब्रेशनल गुणहरु निर्धारण गरि, हाइड्रोजन बन्डलाई QTAIM र रिडिउस्ड डेनसिटी ग्राफ (RDG) को प्रयोग गरेर थप सटीक रूपमा अध्ययन गरिएको थियो। इलेक्ट्रोन लोकलाइजेसन फंक्सन (ELF) को आधारमा, इलेक्ट्रोन लोकलाइज्ड क्षेत्र र डीलोकलाइज्ड क्षेत्रलाई चित्रण गरिएको छ। मोलिकुलर इलेक्ट्रोस्टेटिक पोटेन्सिअल (MEP) मार्फत अणुहरू वरपर रहेको चार्ज वितरणको अवस्थालाई ब्याख्या गरिएको छ । MEP को सहयोगले, इलेक्ट्रोफिलिक र न्यूक्लियोफिलिक साइटहरू पत्ता लगाइएको छ। लोयस्ट अनअकुपाइड मोलिकुलर अर्बिटल इनर्जी (ELUMO), हाइयस्ट अकुपाइड मोलिकुलर अर्बिटल इनर्जी (EHOMO) र तिनीहरूको इनर्जी ग्याप प्रयोग गरि अणुहरूको रासायनिक स्थिरता जाँच गरिएको छ। यसबाहेक, रासायनिक प्रतिक्रियाशीलताको प्रकृति, इनर्जी ग्याप (ΔE), ग्लोबल र लोकल रियाक्तिभिटीका विशेषताहरू स्थापित गरियो। बन्डिङ र एन्टिबन्डिङ बीचको चार्ज डीलोकलाइजेशनको कारणले हुने इस्ट्याविलाइजेसन इनर्जी को निर्धारण गर्न नेचुरल बन्ड अर्बिटल (NBO) को विश्लेषण गरिएको थियो। ताप क्षमता, एन्थाल्पी र एन्ट्रोपी जस्ता मानक थर्मोडायनामिक प्यारामिटरहरूको तापक्रमसँगको सम्बन्धको अध्ययन गरिएको छ । अन्ततः अणुहरूको जैविक गतिविधिहरु अध्ययन गर्न मोलिकुलर डकिङ्ग सिमुलेशनको प्रयोग गरिएको थियो। सेफेलेक्सिनको प्रोटिन म्याट्रिक्स कार्बोनिक एनहाइड्रेस-II र ल्युकोट्रिन A-4 हाइड्रोलेजसँगको बाइन्डिंग गतिविधि, मोलिकुलर डकिङ्ग विधि बाट अनुसन्धान गरिएको थियो। त्यस्तै, मेथाइलडोपाको जैविक गतिविधिहरु प्रोटीन लाइसिन-स्पेशिफिक डेमेथाइलेज 4D- लाइकसँग प्रस्तुत गरिएको छ ।Item Study of the Mixing Behavior of Some Compound Forming Binary Liquid Alloys (Bi-Pb, Cu-In etc)(Institute of Science & Technology, 2023-04) Bhadari, Indra BahadurAlloys are produced by combining two or more metals, and they often develop from their liquid states. Only a small number of metals are used in their pure form; the majority of applications use alloys instead because they have distinctive qualities above and beyond those of the component metals. In the study of liquid science, it is essential to comprehend the properties of liquid alloys because most solid alloys are produced by cooling them from the corresponding liquid states. Liquid alloys are regarded as disordered materials because they lack long-range atomic or magnetic organization. Because disordered materials show a wide range of atomic configurations, this topic is of significant interest to both theoretical and experimental researchers. They have long sought to comprehend the anomalies in the mixing properties of liquid alloys in order to fully comprehend alloying behavior. Theoretical methods can reduce the amount of time and effort necessary and are quite useful in forecasting the mixing properties. So, we have created focused on a theoretical model to study how alloys behave when they are molten. Commonly, the effectiveness of binary alloy production is assessed based on observed thermo-physical characteristics that depart from the ideal mixing state. Departures from ideality manifest as asymmetries in thermodynamic and structural characteristics away from equiatomic composition and are typically attributed to one or more of the following: the size effect, different electronegativity, interactions between solute and solvent atoms, complex formation, or a combination of these factors. The binary liquid alloys can be divided into two categories symmetric and asymmetric, based on the symmetry of the curves reflecting the thermodynamic and microscopic functions. Numerous theoretical approaches have been devised and implemented to examine the thermodynamic and structural properties of binary systems. The Complex Formation Model (CFM) is founded on a fundamental theoretical model. This model makes it possible to express the energetics of a system in terms of the interaction parameters that reproduce the system's thermodynamic properties, as well as the ordering and phase separation processes that are observed in liquid binary alloys. The CFM makes the assumption that, if compounds are formed in the solid state at one or more stoichiometric compositions, then it follows that they are very likely to exist in the liquid state at those same compositions. The alloying behavior of binary solutions can be investigated by making the assumption that complexes are present near to melting points. The molten alloy is considered to be composed of a ternary mixture of A and B atoms, as well as a number of chemical complexes A_p B_q in chemical equilibrium with one another. In this case, p and q are both pairs of small integers that stand for stoichiometric indices of the complex. In the present work, we have examined and explained the mixing behavior of two liquid binary alloys based on Bi, such as Bi-Mg at 975 K and Bi-Pb at 700 K, as well as two In-based alloys, such as Cu-In at 1073 K and In-Pb at 673 K, using the CFM framework. For the aforementioned liquid alloys at a given temperature, the thermodynamic properties, such as free energy of mixing (G_M ), enthalpy of mixing (H_M ), and entropy of mixing (S_M ), structural properties, such as concentration fluctuation in long wave length limit (S_cc (0)) and chemical short range order parameter (α_1 ), and transport property, such as ratio of diffusion coefficients (D_M/D_id ), have been examined. We have calculated the interaction energy parameters 〖(Ψ〗_ij,i,j=1,2,3,i≠j), the energy of complex formation (χ), and the number of complexes (n_3 ) for this purpose. These parameters are used to compute the free energy of mixing (G_M/RT) for each system. Enthalpy of mixing (H_M/RT) and entropy of mixing (S_M/R) have been calculated using these parameters and their temperature coefficients ((∂Ψ_ij)⁄(∂T and ∂χ⁄(∂T ))). Comparing the thermodynamic characteristics of the selected systems, it can be seen that they are in very well agreement with the experimental data reported in the literature. The Bi-Mg system is the most interactive, followed by the Cu-In and Bi-Pb systems, according to a comparison of structural properties (S_cc (0) and α_1 ), the ratio of diffusion coefficients (D_M/D_id ) using the same interaction parameters, and thermodynamic properties. The analysis of these mixing characteristics in the In-Pb liquid alloy, however, shows that segregation does occur in this alloy. We have also used the Budai-Benko-Kaptay (BBK) model to study the viscosity of the selected liquid alloys. For the liquid alloys of Bi-Pb and In-Pb, symmetric viscosity isotherms have been reported; however, Bi-Mg and Cu-In exhibits asymmetry. Within the framework of the updated Butler model, the surface properties of the aforementioned binary alloys, such as surface concentration (c_i^s ) and surface tension (σ), have been investigated. Theoretical analyses show that the component in binary liquid alloys whose surface concentration values are higher than the corresponding ideal values segregates across the surface. It is found that the interaction parameters depend on temperature rather than concentration. To optimize the values of interaction parameters at high temperatures, temperature coefficients and their values at a certain temperature are used. The mixing characteristics of Bi-Pb liquid alloys at 900 K, 1100 K, 1300 K, and 1500 K have been investigated using these optimized values of interaction parameters. The compound-forming propensity of binary liquid systems diminishes with increase in temperature, according to the high temperature investigation of Bi-Pb liquid alloy. The properties of binary liquid alloys at the needed temperature can be carried using this expanded CFM, which is expected to be highly helpful in future work.Item MULTIFRACTAL APPROACH TO THE STUDY OF GORKHA EARTHQUAKE OF 25 APRIL, 2015 NEPAL(Institute of Science & Technology, 2023-02) Tiwari, Ram KrishnaThe devastating earthquake that occurred in the Barpak area of the Gorkha district of Nepal on April 25, 2015, known as the Gorkha earthquake, caused widespread damage and the loss of lives. This study focuses on the central Himalaya region, particularly the area directly impacted by the Gorkha earthquake in 2015, as well as the surrounding regions. This study estimates the fractal dimension of the distribution pattern of the Gorkha earthquake aftershock sequence and the b-value of Gutenberg-Richter law for the earthquakes that occurred between 1964 and 2020 in central Himalaya and vicinity. The data set containing 1126 earthquakes with a completeness magnitude of ≥3.8 is created from the revised International Seismological Centre (ISC) catalogue for the rectangular boundary 26.45°N-30.5°N and 80°E-88.2°E for the study of b-value change. The b-value is estimated by the maximum likelihood estimation (MLE) method. The temporal variation of b-value for the fixed event window (100) shows the increment from 0.44 ± 0.02 to 1.02 ± 0.09 for the period of 21 years (1980 to 2001). The U-shaped variation in b-value was noticed from 2005 to 2015, during which earthquakes from Gorkha to Kodari happened in the region. When the variation in b-value is studied on a long-term basis, the lowest b-value of 0.44 ± 0.06 was noticed for the period between 1984 and 1994, and after 1994, the b-value shows a gradual increase and settles around 1.0 after 2020. The spatial variation of the b-value for the fixed width window shows the variation in the range between 0.59 and 1.0, suggesting the region under study is tectonically active. The b-value around 1.0 for 0 to 11 km of depth suggests the heterogeneity and low strength of the rock. The depth-dependent b-value reveals a significant boundary around the depth 32 km. The contour map shows the low b-value patches (areas) ≤ 0.7, one west and the other east of the 2015 earthquakes, and the areas are overlapped with the zones of the major faults. More importantly, a multifractal analysis of the 2015 Gorkha earthquake's aftershock sequence is presented, focusing on the spatio-temporal distribution of earthquakes from April 25, 2015, to May 14, 2016, for the regions 81.77°–90.41°E and 25.22°–30.15°N. The analysis uses 10,500 earthquakes (Mc = 2.0 ML), divided into 101 windows of 500 events with 100 event shifts. During this period, the box counting dimension (D0) ranged from 0.84 ± 0.07 to 2.39 ± 0.03, and the correlation dimension (D2) ranged from 1.11 ± 0.04 to 1.38 ± 0.03. The generalized dimension spectrum (Dq) showed oscillations in positive q values with consistent peaks from q = 0 to q = 22. From the study, the highest values of the capacity dimension, D0, were found to be 2.28 ± 0.02, 2.39 ± 0.03, and 2.15 ± 0.03 for the temporal windows spanning from 2015-08-15 to 2015-08-26, 2015-11-01 to 2015-11-20, and 2015-11-30 to 2016-01-11, respectively. The study found that the fractal spectrum deviated between D2 and D22, with values ranging from 2.0 to 0.7. This deviation suggests a buildup of strain around an asperity and its subsequent release in the tectonic stress field. The knee-shaped structure of the fractal spectrum suggests that the aftershocks of the Gorkha earthquake show a multifractal structure described by a spectrum of generalized dimensions. Additionally, we found that the distribution of epicenters is not random but rather clusters in certain regions. The temporal correlation dimension (Dt) varies between 0.27 and 0.30 across different time windows, and when calculated for the entire study duration spanning from 1964 to 2020, it yields a value of 0.31 ± 0.004. The low temporal correlation dimension value indicates a high temporal clustering of aftershocks. This high temporal clustering of aftershocks may be due to the interplay of different physical processes, such as stress transfer, and the temporal evolution of the fault system, which can lead to a temporal clustering of aftershocks. The seismic moment release curves for the Gorkha and Kodari (Dolakha) earthquakes in 2015 showed that the majority of the seismic moment was released during the Kodari earthquake. This suggests that the strongest aftershocks tend to carry the most seismic moment in an earthquake sequence. Additionally, it is possible that the high seismic moment release during the Dolakha earthquake was caused by an increase in the rate of plate subduction. A very weak negative correlation between b-value and fractal dimensions of aftershocks distribution means that as the b-value increases (indicating a greater number of small earthquakes relative to larger ones), the fractal dimension decreases (indicating a less complex distribution of aftershocks). This may indicate that as the number of small earthquakes increases, the distribution of aftershocks becomes more homogeneous and less complex. The decline in the number of aftershocks is observed following the Gorkha earthquake within the first 45 days. It is observed that the rate of decline is steep in the first 10 days after the main shock and then gradually slows down. The modified Omori parameter (p) is calculated to be 0.86 ± 0.04, indicating a relatively low temporal decay rate. Additionally, the parameters c and K are calculated to be 0.051 ± 0.019, and 57.9 ± 3.7, respectively. The low value of p compared to the typical value of 1.0 for this study period suggests that the rate of decline in aftershocks has not yet reached equilibrium, and the possibility of additional aftershocks cannot be ruled out. This study provides valuable understandings regarding the spatial distribution of seismic activity in the central Himalayan region, thereby contributing to potential applications in risk evaluation endeavors in the times to come. वि.सं. २०७२ साल बैशाख १२ गते (२५ अप्रिल २०१५) मा मध्य नेपालको गोरखा जिल्लास्थित बारपाक केन्द्रविन्दु बनाएर गएको गोरखा भूकम्पले धेरै जनधनको क्षति गरेको थियो । यस शोधमा सो भूकम्पको प्रभावमा परेको आयाताकार क्षेत्र (२६.४५० उत्तर -३०.५०० उत्तर र ८०.००० पूर्व - ८८.२० पूर्व) मा पर्ने विगतका भूकम्पहरूको अध्ययन गरी बी–मान (बी–भ्यालु) को मापन र गोरखा भूकम्पको पराकम्पनहरूको अध्ययन गरी भग्न आयाम (फ्रेक्टल डाइमेन्सन) को मापन गरिएको छ। यस अध्ययनमा बी–मानको मापन अधिकतम सम्भावनाको अनुमान (म्याक्सिमम लाइक्लिहुड मेथड) बाट गरिएको छ। प्रत्येकमा १०० वटा भूकम्पहरू समेटेर बनाइएको निश्चित विन्डोको आधारमा बी –मानको समयअनुसार (टेम्पोरल) परिवर्तन हेर्दा सन १९८० देखि २००१ सम्मको २१ वर्षको समयमा बी–मान ०.४४±०.०२ देखि १.०२±०.०९ सम्म बढेको पाइएको छ भने अङ्ग्रेजीको यु आकारको परिवर्तन २००५ देखि २०१५ सम्ममा देखिएको छ। दशक अवधिको आधारमा बी–मानको परिवर्तन हेर्दा सबैभन्दा कम (०.४४±०.०६) १९८४ देखि १९९४ को दशकमा देखिन्छ भने १९९४ पछि क्रमिक वृद्धि भई वैशिक औसत (ग्लोबल एभरेज) मान १.० को वरिपरि स्थिर भएको देखिन्छ। निश्चित चौडाइ (फिक्स्ड बीइड्थ) विन्डो बनाएर स्थान अनुसार भिन्नता (स्पेटियल भ्यारिएसन) को आधारमा बी–मानमा गरिएको अध्ययनले ०.५९ देखि १.० सम्म परिवर्तन भएको देखाउँछ। यस परिणामले अध्ययनमा समेटिएको क्षेत्र विवर्तनिक (टेक्टोनिक) रुपले सक्रिय रहेको सङ्केत गर्दछ। हिमालयको सतहभन्दा मुनि गरिएको बी–मानको अध्ययनमा ०–११ कि.मी. गहिराइमा बी–मान १.० को वरिपरि पाइएको छ भने ३२ कि.मि. गहिराइमा बी–मानमा सार्थक परिवर्तन देखिएको छ। बी–मान १.० को वरिपरि रहनुले सक्रिय विवर्तनिक, भूपर्पटी (क्रस्ट) मा रहेको विजायीयता (हेटेरोजिनीटी) र भूपर्पटीमा रहेको चट्टानको तनाब (स्ट्रेस) धान्न सक्ने क्षमताको न्युनतालाई दर्साउँछ। बी–मानका रूपरेखा नक्शा (कन्टुर म्याप) को अध्ययन गर्दा गोरखा भूकम्पको पूर्वतिर र पश्चिमतिर न्यून बी–मान सूचित गर्ने क्षेत्रहरू पाइएको छ र यी क्षेत्रहरू हिमालयमा बिध्यमान मुख्य भ्रंश (थ्रष्ट) सँग अतिव्याप्ति (ओभरलेप) भएको पाइएको छ। यस शोधमा ८१.७७० पूर्व - ९०.४१० पूर्व र २५.२२० उत्तर - ३०.१५० उत्तरमा २५ अप्रिल २०१५ देखि १४ मे २०१६ सम्मका गोरखा भूकम्पको पराकम्पनहरूको भग्न आयाम अध्ययनलाई विशेष जोड दिइएको छ। तीव्रता (म्याग्निचुड) २.० वा सो भन्दा बढी (रिक्टर स्केल) का १०,५०० पराकम्पनहरूलाई प्रत्येकमा ५०० वटा पराकम्पनहरू समाबेश गरी १०१ वटा विन्डो बनाईएको छ। प्रत्येक विन्डोमा पराकम्पनहरू १०० को सङ्ख्यामा सर्दै गएका छन् वा ४०० वटा पराकम्पनहरू अतिव्याप्ति भएका छन्। बाक्शा गणना आयाम (बक्स काउन्टीङ्ग डाइमेन्सन) वा क्षमता आयाम (क्यापासिटी डाइमेन्सन) को मान ०.८४±०.०७ देखि २.३९±०.०३ सम्म र सहसम्बन्ध आयम (कोरिलेसन डाइमेन्सन) को मान १.११±०.००४ देखि १.३८±०.०३ सम्म परिवर्तन भएको देखिन्छ। सामान्यीकृत आयाम (जेनेरलाईज्ड डाइमेन्सन) वर्णक्रम (स्पेक्ट्रम) मानहरू दोलन (ओस्किलेसन) भएको देखिन्छ। सामान्यीकृत आयाम वर्णक्रमको विस्तृत अध्ययन गर्दा बाक्शा गणना आयामको उच्चतम मानहरू २.२८±०.०२, २.३९± ०.०३ र २.१५±०.०३ क्रमशः २०१५–०८–१५ देखि २०१५–०८–२६, २०१५–११–०१ देखि २०१५–११–२० र २०१५–११–३० देखि २०१६–१–११ को समयकालिक विन्डोको लागि पाइएको छ। आयाम वर्णक्रम (डाइमेन्सन स्पेक्ट्रम) मा क्यु (अङ्ग्रेजी अक्षर) को मान २ देखि २२ सम्म परिवर्तन गरी हेर्दा भग्न आयाम २.०–०.७ सम्म घटेको पाइयो। यो विचलनले रूक्षता (एस्पेरिटि) को वरिपरि तनाव (स्ट्रेस) निर्माण र तनावबाट छुटकारा को सङ्केत गर्दछ। भग्न वर्णक्रम (फ्रेक्टल स्पेक्ट्रम) को घुँडा जस्तो वा अवग्रह (सिगमोईड) आकारले गोरखा भूकम्पको पराकम्पनको बाँडफाँड बहुभग्न संरचनामा भएको देखिन्छ। यसको साथै भूकम्पको केन्द्रविन्दु (एपिसेन्टर) हरू निश्चित क्षेत्रहरूमा झुण्ड (क्लष्टर) को रुपमा पाइएको छ। समयकालिक सहसम्बन्ध आयाम (टेम्पोरल कोरिलेसन डाइमेन्स) को मान फरक फरक समय विन्डो को लागि ०.२७ देखि ०.३० बिच रहेको पाइएको छ भने १९६४ देखि २०२० सम्म यसको मान ०.३१±०.००४ रहेको पाइएको छ। यी न्यून मानहरूले पराकम्पनहरूको उच्च अस्थायी झुण्डको सङ्केत गर्दछ। यो उच्च झुण्डको कारण तनावको अन्र्तरक्रिया, नयाँ भ्रंशहरूको निर्माण हुन सक्छ। भूकम्पजनिक मोमेन्ट प्रसारण वक्र (साइजमिक मोमेन्ट रिलिज कर्व) हेर्दा कोदारी (दोलखा) भूकम्प पछि भूकम्पजनिक शक्तिको रिलिज बढी भएको पाइएको छ। जसले शक्तिशाली पराकम्पनले बढी असर गर्छ भन्ने कुरालाई प्रष्टयाउँछ। भूकम्पजनिक शक्ति बढी रिलिज हुनुको कारण भू-पाता सबडक्सन दर बढेको पनि हुन सक्छ। यस अध्ययनमा बी–मान र भग्न आयामको बिचमा कमजोर नकरात्मक सहसम्बन्ध देखिएको छ जसले बी–मान बढ्दै जाँदा भग्न आयमको मान घट्दै जाने सकेत गर्दछ। यसको साथसाथै स–साना पराकम्पनहरूले भूकम्पीय क्षेत्रमा कम जटिल स्थिति बन्दै गएको पनि सङ्केत गर्दछ। गोरखा भूकम्पको पहिलो ४५ दिन सम्मको पराकम्पनहरूको ओमरी नियम अनुसार अध्ययन गर्दा पराकम्पनहरूको सङ्ख्या पहिलो १० दिनमा तीब्र रुपमा घटेको देखिन्छ र त्यसपछि क्रमिक रुपमा घटेको पाईएको छ। परिमार्जित ओमरी मापदण्ड (प्यारामिटर) पि (अङ्ग्रेजी अक्षर) को मान ०.८६±०.०४ मापन गरिएको छ जसले अपेक्षाकृत कम अस्थायी क्षयदर सङ्केत गर्दछ। अन्य मापदण्डहरू सी (अङ्ग्रेजी अक्षर) र के (अङ्ग्रेजी अक्षर) को मान क्रमशः ०.०५१±०.०१९ र ५७.९±३.७ मापन गरिएको छ। यस अध्ययनबाट प्राप्त पी को मान सामान्य मानिने पी को मान (१.०) भन्दा कम छ जसले पराकम्पनमा आएको गिरावट दर अझै सन्तुलनमा पुग्न नसकेको सङ्केत गर्दछ र अतिरिक्त पराकम्पनहरूको सम्भावनालाई नर्कान नसकिने बताउँछ। अन्तमा यस अध्ययनले मध्य हिमाली क्षेत्रमा भूकम्पीय गतिविधिको जानकारी गराई समयमा जोखिम मुल्याङ्कनका प्रयासहरूमा लाग्न जोड दिन्छ। यसले गर्दा भविष्यमा हुने धनजनको क्षतिमा कमी ल्याउन सकिने छ।