Nepal Journal of Science and Technology最新文献_第4页

Comparative Analysis of Diffusers for Micro Wind Turbine 微型风力机扩散器的比较分析

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i2.45796

Roshan Kumar Chhetri, Dilip Bhattarai Upadhyay, Niraj R. Ghimire

{"title":"Comparative Analysis of Diffusers for Micro Wind Turbine","authors":"Roshan Kumar Chhetri, Dilip Bhattarai Upadhyay, Niraj R. Ghimire","doi":"10.3126/njst.v20i2.45796","DOIUrl":"https://doi.org/10.3126/njst.v20i2.45796","url":null,"abstract":"With the increase in demand for clean energy, a micro wind turbine would be the best option for remote and urban residential areas. Installing wind turbines is not feasible in most land areas due to low or inadequate wind speed. The energy generated by the wind turbine is directly proportional to the cube of wind velocity. So, if we manage to increase wind speed slightly, it would increase energy significantly. One approach to solving problems in areas with low wind speed is using Diffuser Augmented Wind Turbine (DAWT). In DAWT, the turbine blades are typically surrounded by a duct which increases the cross-sectional area in the stream-wise direction. Since a diffuser encloses the wind turbine, the pressure behind the turbine will drop, which results in an increasing wind velocity. Different types of diffusers have been introduced to increase wind velocity. The main aim of the research is to perform a comparative analysis of four different types of diffusers to increase the power output of wind turbines. The CFD simulation of Plain Diffuser, Plain Diffuser with Inlet Shroud, Flanged Diffuser, and Flanged Diffuser with Inlet Shroud is performed to determine the maximum velocity each diffuser produced. With the solution from the simulation, a comparative analysis of each diffuser is conducted, and the results are further verified with the previous studies on DWAT. And Flanged Diffuser is found to be optimum with an increase in power generation up to 3.6 times compared to a bare wind turbine.","PeriodicalId":129302,"journal":{"name":"Nepal Journal of Science and Technology","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116605247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spring Water Sources Assessment and Forest Area Dynamics in Roshi and Melamchi Watersheds Roshi和Melamchi流域泉水水源评价与森林面积动态

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i2.45801

S. Chaudhary, K. R. Kafle, Govinda Baniya, S. Shrestha, Rajiv Giri, B. Shrestha, E. Sigdel

引用次数: 0

Comparative Studies on Antioxidant Activity of Ten Medicinal Plants Collected From the Ilam District of Nepal 尼泊尔伊拉姆地区10种药用植物抗氧化活性的比较研究

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43363

S. K. Kalauni, Muna Niraula, P. Thapa, Ishwor Pathak

{"title":"Comparative Studies on Antioxidant Activity of Ten Medicinal Plants Collected From the Ilam District of Nepal","authors":"S. K. Kalauni, Muna Niraula, P. Thapa, Ishwor Pathak","doi":"10.3126/njst.v20i1.43363","DOIUrl":"https://doi.org/10.3126/njst.v20i1.43363","url":null,"abstract":"Methanol extracts of ten medicinal plants collected from Ilam district were prepared and a preliminary phytochemical screening was performed. Phytochemical test revealed that selected plant samples contain alkaloids, flavonoids, terpenoids, glycosides, quinones, reducing sugars, coumarin, polyphenols, and saponins. The antioxidant properties of ten samples were evaluated by using DPPH free radical scavenging assay and their inhibitory concentration for 50% inhibition (IC50 values) for antioxidant properties were calculated. Among all ten studied samples, IC50 values of extracts of barks of Atrocarpus lakoocha (41.42±3.1 µg/mL) and flowers of Woodfordia fructicosa (41.89±2.5 µg/ mL) were very close to that of standard ascorbic acid (38.74±2.5 µg/mL). Similarly, flowers of Rhododendron arboreum (45.55±2.2 µg/mL), roots of Vetiveria zizanoids (46.22±2.0 µg/mL) and rhizomes of Mirabilis jalapa (48.99±3.0 µg/mL) also showed strong activity against DPPH free radicals. These results showed that these plants could be the potential sources of natural antioxidants in the food and/or pharmaceutical industry","PeriodicalId":129302,"journal":{"name":"Nepal Journal of Science and Technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122684895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Phytochemical Screening, Antioxidant and Antidiabetic Activities of Extracts of Leaves and Seeds of Carica papaya 番木瓜叶和种子提取物的植物化学筛选及其抗氧化和抗糖尿病活性

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43362

Shanta Pokhrel, Puja Karki

{"title":"Phytochemical Screening, Antioxidant and Antidiabetic Activities of Extracts of Leaves and Seeds of Carica papaya","authors":"Shanta Pokhrel, Puja Karki","doi":"10.3126/njst.v20i1.43362","DOIUrl":"https://doi.org/10.3126/njst.v20i1.43362","url":null,"abstract":"The phytochemicals, phenolic, flavonoid contents, and antibacterial, antioxidant and antidiabetic activities of leaves and seeds extract of Carica papaya via Soxhlet extraction were investigated. The phytochemical screening indicated different bioactive compounds such as saponins, alkaloids, glycosides, tannins, polyphenols, steroids, and flavonoids in different extracts. The total phenolic content (TPC) was determined spectrophotometrically by Folin–Ciocalteu reagent method and aluminium chloride reagent to measure total flavonoid content (TFC). TPC was found more in leaf methanol extract (LME) (93.18±0.40 mg GAE/g) than that in seed methanol extract (SME) (89.14±0.45 mg GAE/g). Comparatively, the flavonoid content was found more in LME (18.85±0.061 mgQE/g) than in SME (16.64±0.065 mgQE/g). The antioxidant activity was assessed for LME and SME by DPPH radical scavenging activity and IC50 values. The IC50 values of LME and SME were 43.54±0.007 and 15.48±0.13µg/mL, respectively. Thus, seeds methanol extract showed better antioxidant activity than leaves methanol extract. The antidiabetic assay was performed via α- amylase inhibition method. Among the selected parts (seeds and leaves), methanol seed extract exhibited high α-amylase inhibition with an IC50 value of 46.99±0.018 µg/mL. The study explored the potential value of Carica papaya in medicinal applications.","PeriodicalId":129302,"journal":{"name":"Nepal Journal of Science and Technology","volume":"196 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124928567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Transit of Sun Across Constellation Sagittarius and Variation of Secondary Gamma Radiation Flux in January, 2021 at Udaipur, India 2021年1月印度乌代普尔太阳穿越人马座和二次伽马辐射通量的变化

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43351

P. Purohit, D. Pareek

引用次数: 0

Evaluation of Zucchini (Cucurbita pepo L.) Genotypes for Spring Season Production in the Mid–Hills of Nepal 西葫芦(Cucurbita pepo L.)评价尼泊尔中部山区春季生产的基因型

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43356

S. Shrestha, M. Dhakal, Sangeeta Sapkota, I. P. Gautam, S. Pandey, Y. Shrestha

{"title":"Evaluation of Zucchini (Cucurbita pepo L.) Genotypes for Spring Season Production in the Mid–Hills of Nepal","authors":"S. Shrestha, M. Dhakal, Sangeeta Sapkota, I. P. Gautam, S. Pandey, Y. Shrestha","doi":"10.3126/njst.v20i1.43356","DOIUrl":"https://doi.org/10.3126/njst.v20i1.43356","url":null,"abstract":"Zucchini (Cucurbita pepo L.) is one of the most popular and demanded vegetable in Nepal. Seedlings of seven genotypes of squash gourd; Super Squash Ball, Squash Long, Squash Light, Squash Green Ball, Squash Green House Sondo V (check) and Grey Zucchini (check) were transplanted on second week of March in two consecutive years; 2016 and 2017 in field condition at Khumaltar with a spacing of 90 x 90 cm in four replications. The standard recommended dose of fertilizers (240:180:60 NPK kg/ha + 15 ton FYM/ha) and minimum pesticide and fungicide was applied. The main objective of this experiment was to find out suitable high yielding and insect pest and disease tolerant hybrid Zucchini cultivars for commercial production in mid-hills of Nepal. Crops were evaluated for their vegetative, insect pest and disease, and yield attributing parameters. Among the tested genotypes; Squash Long was found highly uniform, vigorous, least virus and insect damage, significantly higher number of fruits(8.6), and yield (3894 g) per plant and yield (46.89 t/ha) followed by Super Squash Ball having highly uniform, less insect and powdery mildew damage, significantly higher number of fruits (8.5) and yield (2565 g) per plant and yield (29.28 t/ha) as compared to check Sondo V and Grey Zucchini where Sondo V had yield (22.50 t/ha and 1703 g/plant), number of fruits (5.6), per plant respectively. Squash Long and Super Squash Ball have been selected and recommended for cultivation during spring season in mid-hills of Nepal.","PeriodicalId":129302,"journal":{"name":"Nepal Journal of Science and Technology","volume":"170 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126746928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of the leaf-feeding beetle Zygogramma bicolorata Pallister on the growth of Parthenium hysterophorus L. in climatically different locations of Nepal 尼泊尔不同气候条件下食叶甲虫双色天牛对宫草生长的影响

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43355

Seerjana Maharjan, B. Shrestha, Anjana Devktoa, P. Aryal, Muniappan Rangaswam, P. K. Jha

{"title":"Impact of the leaf-feeding beetle Zygogramma bicolorata Pallister on the growth of Parthenium hysterophorus L. in climatically different locations of Nepal","authors":"Seerjana Maharjan, B. Shrestha, Anjana Devktoa, P. Aryal, Muniappan Rangaswam, P. K. Jha","doi":"10.3126/njst.v20i1.43355","DOIUrl":"https://doi.org/10.3126/njst.v20i1.43355","url":null,"abstract":"The leaf-feeding beetle, Zygogramma bicolorata Pallister, one of the biocontrol agents against Parthenium hysterophorus L., having been established at several locations of Nepal. However, the damage to P. hysterophorus by the beetle has not been assessed quantitatively under different climatic conditions so far. The study was carried out at two locations, namely Hetauda with a tropical climate (540 m asl) and Kathmandu with a subtropical climate (1300 m asl) to evaluate the impact of the beetle on P. hysterophorus. Beetles were released in two different densities (one and two beetles/plant) during the early flowering period (early August). Individual plants were harvested when the initial signs of senescence were observed in mid-September. Plant height and leaf, stem, root biomass of each harvested individual was measured. Plant height, leaf biomass, and stem biomass were significantly higher at the subtropical site than at tropical sites and declined with the increasing density of beetle at both locations. Root:shoot ratio increased with the increasing density of beetle at both locations. The plant height, leaf biomass, and shoot biomass decreased up to 35 %, 73 %, and 54 % respectively at the tropical site and 9 %, 58 %, and 26 % respectively at the subtropical site. Root:shoot ratio increased by 76 % in the tropical site and 30 % in the subtropical site. The present study, therefore, suggests that mass-rearing and releasing of the beetle could be an effective management tool for the biological control of P. hysterophorus in tropical and subtropical climates of Nepal.","PeriodicalId":129302,"journal":{"name":"Nepal Journal of Science and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128909258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of different planting time and varieties on Growth and Yield of African Marigold (Tagetes erecta) in the Kavre district, Nepal 尼泊尔Kavre地区不同种植时间和品种对非洲万寿菊生长和产量的影响

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43349

M. Dhakal, A. B. Pun, Shandesh Bhattarai

{"title":"Effect of different planting time and varieties on Growth and Yield of African Marigold (Tagetes erecta) in the Kavre district, Nepal","authors":"M. Dhakal, A. B. Pun, Shandesh Bhattarai","doi":"10.3126/njst.v20i1.43349","DOIUrl":"https://doi.org/10.3126/njst.v20i1.43349","url":null,"abstract":"A field experiment was conducted to study the effect of different planting time on growth and flowering attributes of different varieties of African marigold at Kavre district of Nepal during the year of 2014 to 2017. The experiment consisted of four replications and was laid out in a two factorial RCB design. Six treatment combinations consisting of two open pollinated varieties of marigold viz. Calcattia Orange and Calcattia Yellow and three planting time viz. 1st January 2015, 15th February 2015 and 30th March 2015 were evaluated. The pooled analysis of two years’ data showed a significant influence of varieties and planting dates on vegetative growth and flower yield and yield attributing characters Flowering duration differed significantly with variety and its interaction with date of planting. Longer duration of flowering was observed by Calcattia Orange (57.58 days) followed by Calcattia Yellow (53.50 days). 1st January planting of Calcattia Orange exhibited significantly the longest flowering duration (62.00 Days). The flower yield per plant was the highest in Calcattia Orange (894.3 gm/plant) than Calcattia Yellow (815.3 gm/plant). Similarly, 1st January planting had the highest flower yield/plant (1033.1 g/plant) followed by 15th February planting (854.9 gm/plant) and 30th March planting (676.4 g/plant). Although not significant, Calcattia Orange planted on 1st January showed better results in terms of Flower yield /plant (1081 g), Number of flowers per plant and flower size as compared to other treatment combinations and significantly the highest duration of flowering (62.00 days) along with attractive orange color under Kavre condition.","PeriodicalId":129302,"journal":{"name":"Nepal Journal of Science and Technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121770636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

MUNAA Agriculture Market: Connecting Home to Abroad MUNAA农业市场:连接国内外

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i2.45772

G. Rizal, Y. Karki, Jiwan Prabha Lama, Yubaraj Gurung

{"title":"MUNAA Agriculture Market: Connecting Home to Abroad","authors":"G. Rizal, Y. Karki, Jiwan Prabha Lama, Yubaraj Gurung","doi":"10.3126/njst.v20i2.45772","DOIUrl":"https://doi.org/10.3126/njst.v20i2.45772","url":null,"abstract":"Nepalese diaspora has globalized Nepal’s culture, tradition, value, festival, celebration, food, and goods. The Nepalese people have special liking of inherent tastes, flavor, ingredients, cuisine specificities, and indigenous commodities of Nepal. The Non-Resident Nepalese Association (NRNA) and its vast memberships abroad seek such commodities in places where they live. An organization under the Joint Cooperation of Agriculture Promotion Committee of NRNA, Mutual Understanding between NRNA and Agriculture Authority (MUNAA) Agriculture Limited, a company registered with the Bagmati Province with a mandate to work in all provinces of Nepal and abroad, has a mission to connect Nepalese people at home and abroad with the Nepalese agricultural products. MUNAA trades hygienic, safe, fresh, and processed Nepalese food products with the ‘safe food, safe life’ slogan under the ‘MUNAA’ brand. The government of Nepal has adopted favorable agricultural policies that aim to increase production sustainably, substitute imports, and expand export to minimize trade deficits. In addition to following government policies, MUNAA has plans to import technologies for value addition that will benefit both the producers and consumers as per the expectation of the government and Nepalese people at home and abroad.","PeriodicalId":129302,"journal":{"name":"Nepal Journal of Science and Technology","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131181718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Towards Creating Smart Cities in Nepal 在尼泊尔创建智慧城市

Nepal Journal of Science and Technology Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i2.45769

Ambika P. Adhikari, K. Bhattarai

{"title":"Towards Creating Smart Cities in Nepal","authors":"Ambika P. Adhikari, K. Bhattarai","doi":"10.3126/njst.v20i2.45769","DOIUrl":"https://doi.org/10.3126/njst.v20i2.45769","url":null,"abstract":"Many urban centers in the world are seeking to become smart cities. Nepali city leaders are also aspiring to make their cities smart. A smart city basically has clever improvements made in three sectors of its operations: technological, human, and institutional. Globally, many cities have recently made impressive enhancements in at least one or more of these areas. Nepal’s National Planning Commission (NPC) in 2016 had released a concept paper on smart cities for Nepal, defining smart cities as sustainable, information and technology-based, with high quality services and replicable (NPC 2016). As most Nepali cities still operate with limited infrastructure, services, and amenities, making them smart is a challenging task. However, some elements of a smart city can be incrementally and selectively implemented by the Nepali urban governments. This paper assesses the successes and challenges in some of the smart cities globally, and as an example assesses the pollution reduction and efficiency impact of adopting a bus-rapid transit system in Nepal. It is seen that a Bus Rapid Transit (BRT) system for the Kathmandu Valley consisting of electrical buses, will drastically reduce air pollution, and improve mobility for the residents. Urban leaders in Nepal can begin to identify such a transit related and other smart elements to be gradually implemented in their cities which will improve efficiency of urban services, enhance quality of life for the urban residents, and promote sustainability of the overall urban system.","PeriodicalId":129302,"journal":{"name":"Nepal Journal of Science and Technology","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131621729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2