检索结果-南通市图书馆

Effect of ultrasonic assisted sintering on mechanical properties and degradation behaviour of Mg15Nb3Zn1Ca biomaterial

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2021年第6期9卷 1989-2008页

作者： Ajit kumar Pulak M pandey Department of Mechanical Engineering Indian Institute of TechnologyDelhiNew Delhi 110016India

The present work investigates the effect of ultrasonic power(%)and the time of ultrasonic vibration on the sintered density and ultimate compressive strength(UCS)of Mg15Nb3Zn1Ca fabricated using ultrasonic assisted conventional sintering(UACS).The customized UACS setup was designed and manufactured to conduct the experimentations.A customized ultrasonic stepped horn assembly was used for providing vibrations to the sample during ***,to evaluate the efficacy of ultrasonic vibration parameters,the developed setup was used to sinter Mg15Nb3Zn1Ca composite *** study unveiled an increased sintered density and UCS of the fabricated sample by the increase in ultrasonic power(%).Moreover,a decrease in sintered density and UCS was observed with an increase in the time of ultrasonic vibration beyond a certain *** sintered with the assistance of ultrasonic vibration at 100%ultrasonic power,and 20 min of ultrasonic vibration resulted in a sintered density of 1.928±0.062 g·cm^(-3)and UCS of 234.9±12.3 *** obtained mechanical properties of the fabricated sample were comparable to the properties of cortical *** surface morphology and elemental compositions of samples fabricated using UACS declared a fair dispersion of reinforcement in the matrix containing merely the source *** results of corrosion test have showed that the assistance of ultrasonic vibration suppressed the degradation behaviour of the sintered sample after performing electrochemical study of samples using 3-electorde cell ***15Nb3Zn1Ca fabricated using UACS showed a 50.18%and 9.08%of reduction in corrosion rate over conventionally sintered pure Mg and Mg15Nb3Zn1Ca *** addition,electrochemical impedance spectroscopy(EIS)results indicated an enhanced corrosion resistance of the Mg15Nb3Zn1Ca composite material when fabricated at 100%of ultrasonic power with 20 min of vibration *** from that,electrochemical equivalent circuits also result

关键词： Ultrasonic assisted sintering Magnesium Corrosion EIS Mechanical properties

A Novel Approach for Enhancement of Geometric and Contrast Resolution Properties of Low Contrast Images

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2018年第2期5卷 628-638页

作者： Koushlendra kumar Singh Manish kumar Bajpai Rajesh kumar pandey Department of Computer Science and Engineering National Institute of Technology Jamshedpur 831014 India Indian Institute of Information Technology Design & Manufacturing Jabalpur MP 482005 India Department of Mathematical Sciences In- dian Institute of Technology Varanasi U.P. 221005 India

The present work encompasses a new image enhancement algorithm using newly constructed Chebyshev fractional order differentiator. We have used Chebyshev polynomials to design Chebyshev fractional order differentiator. We have generated the high pass filter corresponding to it. The designed filters are applied for decomposing the input image into four bands and low-low(L-L) sub-band is updated using correction coefficients. Reconstructed image with updated L-L sub-band provides the enhanced image. The visual results obtained are encouraging for image enhancement. The applicability of the developed algorithm is illustrated on three different test *** effects of order of differentiation on the edges of images have also been presented and discussed.

关键词： Chebyshev polynomial based approximation contrast enhancement fractional order differentiator

The Curation of Genetic Variants: Difficulties and Possible Solutions

在线全文

学校读者我要写书评

暂无评论

Genomics, Proteomics & Bioinformatics 2012年第6期10卷 317-325页

作者： Kapil Raj pandey Narendra Maden Barsha Poudel Sailendra Pradhananga amit kumar Sharma Deerwalk Services Department of Microbiology Bangalore University Central Department of Microbiology Tribhuvan University Department of Bioinformatics Wageningen University Department of Biotechnology Kathmandu University

The curation of genetic variants from biomedical articles is required for various clinical and research purposes. Nowadays, establishment of variant databases that include overall information about variants is becoming quite popular. These databases have immense utility, serving as a user-friendly information storehouse of variants for information seekers. While manual curation is the gold standard method for curation of variants, it can turn out to be time-consuming on a large scale thus necessitating the need for automation. Curation of variants described in biomedical literature may not be straightforward mainly due to various nomenclature and expression issues. Though current trends in paper writing on variants is inclined to the standard nomenclature such that variants can easily be retrieved, we have a massive store of variants in the literature that are present as non-standard names and the online search engines that are pre- dominantly used may not be capable of finding them. For effective curation of variants, knowledge about the overall process of curation, nature and types of difficulties in curation, and ways to tackle the difficulties during the task are crucial. Only by effective curation, can variants be correctly interpreted. This paper presents the process and difficulties of curation of genetic variants with possible solutions and suggestions from our work experience in the field including literature support. The paper also highlights aspects of interpretation of genetic variants and the importance of writing papers on variants following standard and retrievable methods.

关键词： Difficulties in curation Automated curation Manual curation Interpretation of variants

Trends in major and minor meteorological variables and their influence on reference evapotranspiration for mid Himalayan region at east Sikkim, India

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2016年第2期13卷 302-315页

作者： Shweta YADAV Proloy DEB Sonu kumar Vanita pandey Pankaj kumar pandey Water Engineering and Management Asian Institute of TechnologyPathumthani 12120Thailand Centre for Water Climate and Land-Use(CWCL)Faculty of Science and Information TechnologySchool of Environmental and Life SciencesUniversity of NewcastleCallaghanNewcastle 2308Australia Department of Agricultural Engineering Northeastern Regional Institute of Science and TechnologyNirjuliArunachal Pradesh 791109India Department of Soil and Water Engineering College of Agricultural Engineering and Post Harvest TechnologyRanipoolSikkim 737135India

Estimation of evapotranspiration(ET) for mountain ecosystem is of absolute importance since it serves as an important component in balancing the hydrologic *** present study evaluates the performance of original and location specific calibrated Hargreaves equation(HARG) with the estimates of Food and Agricultural Organization(FAO)Penman Monteith(PM) method for higher altitudes in East Sikkim,*** results show that the uncalibrated HARG model underestimates ET_0 by 0.35 mm day^(-1) whereas the results are significantly improved by regional calibration of the *** addition,this paper also presents the variability in the trajectory associated with the climatic variables with the changing climate in the study *** Mann-Kendall(MK) test was used to investigate and understand the mean monthly trendof eight climatic parameters including reference evapotranspiration(ET_0) for the period of *** of ET_0 was estimated for the calculations done by FAO PM *** outcomes of the trend analysis show significant increasing(p ≤ 0.05) trend represented by higher Z-values,through MK test,for net radiation(Rn),maximum temperature(Tmax) and minimum temperature(Tmin),especially in the first months of the ***,significant(0.01 ≥ p ≤0.05) decreasing trend in vapor pressure deficit(VPD)and precipitation(P) is observed throughout the *** trend in sunshine duration,VPD and ET_0 is found in spring(March- May) and monsoon(June –November) *** result displays significant(0.01≤ p ≤ 0.05) decreasing ET_0 trend between(June- December) except in July,exhibiting the positive relation with VPD followed by sunshine duration at the ***,the study emphasizes the importance of trend analysis of ET_0 and other climaticvariables for efficient planning and managing the agricultural practices,in identifying the changes in the meteorological parameters and to accurately assess the hydrologic water balance of the hilly regions.

关键词：参考作物蒸散量气候变化喜马拉雅地区印度水文循环农业组织区域标定日照时数

Microstructure studies of air-plasma-spray-deposited CoNiCrAlY coatings before and after thermal cyclic loading for high-temperature application

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2016年第8期23卷 934-942页

作者： Dipak kumar K.N.pandey Dipak kumar Das Mechanical Engineering Department Motilal Nehru National Institute of TechnologyAllahabad-211004India Defense Metallurgical Research Laboratory Hyderabad-500058India

In the present study, bond-coats for thermal barrier coatings were deposited via air plasma spraying（APS） techniques onto Inconel 800 and Hastelloy C-276 alloy substrates. Scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, X-ray diffraction（XRD）, and atomic force microscopy（AFM） were used to investigate the phases and microstructure of the as-sprayed, APS-deposited Co Ni Cr Al Y bond-coatings. The aim of this work was to study the suitability of the bond-coat materials for high temperature applications. Confirmation of nanoscale grains of the γ/γ′-phase was obtained by TEM, high-resolution TEM, and AFM. We concluded that these changes result from the plastic deformation of the bond-coat during the deposition, resulting in Co Ni Cr Al Y bond-coatings with excellent thermal cyclic resistance suitable for use in high-temperature applications. Cyclic oxidative stability was observed to also depend on the underlying metallic alloy substrate.

关键词： thermal barrier coatings coating structure plasma spraying thermal cycle high-temperature applications microstructure studies

Development of Mg based biomaterial with improved mechanical and degradation properties using powder metallurgy

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2020年第3期8卷 883-898页

作者： Ajit kumar Pulak M.pandey Department of Mechanical Engineering Indian Institute of TechnologyDelhi110016India

In the present work,biocompatible materials such as niobium(Nb),zinc(Zn)and calcium(Ca)have been blended with magnesium(Mg)to develop a novel biomaterial(BM)with improved mechanical and corrosion resistant *** metallurgy(PM)technique was used to fabricate Mg based *** powder of all aforementioned materials were mixed homogenously in specific quantities to create a uniform composite *** order to analyse the influence of process parameters on the mechanical properties of the fabricated part,experiments were performed considering central composite design(CCD).The effect of powder metallurgical parameters namely percentage Nb,compaction pressure,heating rate,sintering temperature and soaking time on the ultimate compressive strength(UCS)and sintered density was studied in the present *** was found that the UCS and sintered density increased with increase in compaction pressure,heating rate and sintering *** results also revealed that the increase in soaking time and percentage Nb,increased sintered density and UCS to a certain *** increase in these two parameters,sintered density and UCS *** electron microscopy(SEM)images of the fabricated samples showed reduction in porosity with the increase in heating ***,X-ray diffraction(XRD)results revealed that no other phase or impurities were found during sintering of Mg based *** optimum process parameters were obtained to develop Mg based BM for maximum UCS and sintered ***,the Mg based BM samples fabricated at optimum process parameters were used for corrosion testing in simulated body fluid(SBF)solution at a temperature of 37±0.5℃.The Mg based BM yielded improved mechanical properties with reduced corrosion rates as compared to pure Mg.

关键词： Biomaterials Powder metallurgy Magnesium Corrosion Metal matrix composite

Swallowing of Casson fluid in oesophagus under the influence of peristaltic waves of varying amplitude

在线全文

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2017年第2期10卷 49-64页

作者： Sanjay kumar pandey Shailendra kumar Tiwarit Indian Institute of Technology (BHU) Varanasi 221005 India

The experimentally verified fact that there is a high pressure zone in the lower part of the oesophagus has established that the earlier models fall short of representing the realistic swallowing process in the oesophagus. Since the high pressure is created by gradually increasing amplitudes of peristaltic waves, swallowing of Casson fluid in oesophagus is mathematically remodeled. It is revealed that in the case of exponentially increasing amplitude, pressure is non-uniformly distributed for different cycles. Pressure increases along the entire length of the oesophagus; and finally toward the end of the oesophageal flow, it increases quite significantly, probably to ensure delivery into the stomach. This is a similar observation for Newtonian as well as non-Newtonian fluids but Casson fluids need more pressure; and hence more efforts are required by the oesophagus to transport the fluid forward. When wave amplitude is small, flow rates are small. In such a case, Casson fluid requires higher flow rates for reflux to occur in comparison to Newtonian fluid. This tendency gradually diminishes with increasing amplitude. For a particular value of amplitude, there is no difference; and beyond that the trends are quite opposite. Thus, Casson fluid is found to be less prone to reflux near the wall. It is also concluded that for the Newtonian fluid as well as for the non-Newtonian Casson fluid, reflux is more likely to occur with increasing amplitude and it is further augmented by the addition of amplifying parameter.

关键词： Oesophagus peristalsis varying amplitude Casson fluid

Targeting biosignatures of hyperglycemia and oxidative stress in diabetes comorbid depressive rats: effectiveness of hydroethanolic extract of the whole plant of Ludwigia octovalvis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Traditional Medicine Research 2023年第2期8卷 13-20页

作者： Stuti pandey Pawan kumar pandey Alakh Niranjan Sahu Himanshu Verma Manmath kumar Nandi Department of Medicinal Chemistry Faculty of AyurvedaInstitute of Medical SciencesBanaras Hindu UniversityVaranasi 221005Uttar PradeshIndia Department of Pharmaceutical Engineering&Technology Indian Institute of Technology Banaras Hindu UniversityVaranasi 221005Uttar PradeshIndia

Background:The prime objective of the current research was to evaluate the whole plant hydroalcoholic extract of Ludwigia octovalvis(HLO)against hyperglycemia,and oxidative stress biomarkers in rats induced with diabetes comorbid depression,diabetes comorbid depression(streptozotocin-nicotinamide+electric footshocks).Methods:2,2-Diphenyl-1-picrylhydrazyl assay of HLO versus ascorbic acid was *** of 200 and 400 mg/kg body weight/day HLO doses versus 25 mg/kg body weight/day metformin was studied through insulin,glucose,superoxide dismutase,lipid peroxidation,catalase,and behavioral assessment(forced swim and open field tests).Results:IC50 values of HLO and ascorbic acid were 33.52 and 27.86μg/mL *** the HLO doses showed intended results with respect to oxidative stress biomarkers in diabetes comorbid depression rats in comparison to *** field test showed better results for HLO in diabetes comorbid depression ***,hypoglycemic effects,and forced swim test performance of metformin was slightly higher than the 400 mg dose,followed by the 200 mg dose of *** gallate,gallic acid,β-sitosterol,and quercetin in HLO might resulted in attenuating diabetic as well as depression ***:Inhibition of glucosidase and lipase activity,and AMP-activated protein kinase phosphorylation might be the possible biochemical changes occurred in HLO treated rats.

关键词： 2,2-diphenyl-1-picrylhydrazyl assay brain homogenate insulin superoxide dismutase content catalase activity lipid peroxidation

Correlates of avifaunal diversity along the elevational gradient of Mardi Himal in Annapurna Conservation Area,Central Nepal

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Avian Research 2020年第3期11卷 201-214页

作者： Naresh pandey Laxman Khanal Mukesh kumar Chalise Central Department of Zoology Institute of Science and TechnologyTribhuvan UniversityKathmandu 44613Nepal Nepal Biodiversity Research Society(NEBORS) Lalitpur 44700Nepal

Background:Patterns of biological diversity and richness can vary along the elevational gradients among mountain systems making it difficult to conclude the general *** drivers of such pattern are also poorly known in the southern flank of the Himalaya due to limited ***,we assessed the species richness,seasonal patterns and drivers of avian diversity along an elevational gradient on Mardi Himal trekking trail,a newly open tourist route in Annapurna Conservation Area of the central ***:Two surveys(winter and summer seasons of 2019)were conducted from the bank of Seti-Gandaki River confluence(1030 m above sea level,asl)up to the Low Camp(3050 m asl)of the Mardi *** point count method was employed in every 100 m rise in the *** indices were calculated and bird abundance data on species,sites,seasons and environmental variables were *** linear model,polynomial regression and ordinary least square regression were performed to examine the importance of environmental factors in shaping the avian richness ***:A total of 673 individuals of birds belonging to 112 species,of which 72 in winter and 80 in summer,were *** observed a hump-shaped pattern of the overall species richness along the elevational *** richness pattern remained consistent even when explored by season,for winter and summer *** indices were found higher during the *** and mean monthly temperature in both seasons showed non-linear relation with avian species *** exhibited positive association in summer whereas the same in winter was negatively correlated with avian species *** to the nearest water source and the nearest human settlement were negatively correlated with the richness of ***-ranged and insectivorous birds were under the strong influence of gradients on climatic variables like temperature and ***:We conc

关键词： Annapurna Conservation Area Avian richness Central Himalaya Elevation