检索结果-南通市图书馆

Journal of Mountain Science 2018年第11期15卷 2453-2465页

作者： Anudip GOGOI Uttam kumar sahoo Department of Forestry Mizoram University

Impact of anthropogenic disturbance on species diversity and vegetation structure of a lowland tropical rainforest was studied in the foothills of Eastern Himalaya, India. Tree species richness,density, basal area and the diversity indices were found significantly(P100 cm dbh class in all three sites. Density of the matured trees decreased with increasing DBH whereas, tree basal area tended to increase with increasing DBH in all three sites. Tree species richness was highest in the lower DBH classes.62.07% of the total tree species regenerated in the largely undisturbed site followed by 50% in the mildly disturbed and 26.32% in the highly disturbed *** overall regeneration condition was found to be good in the largely undisturbed site. Mildly disturbed site exhibited fair regeneration and so was in the highly disturbed site. Discernable variations in species composition, diversity, regeneration and tree population structure revealed the impact of anthropogenic disturbances on rainforest vegetation dynamics. Higher degree of disturbance was furtherly found not only affecting species diversity but also promoting the growth of invasive weed *** of Hydnocarpus kurzii and Crypteronia paniculata in the highly disturbed site also indicated that these les

关键词： Biodiversity Deforestation Abundance Vegetation Dynamics Conservation Management

Rutting prediction models for flexible pavement structures: A review of historical and recent developments

在线全文

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2021年第3期8卷 315-338页

作者： Auinash kumar Singh Jagdish Prasad sahoo Department of Civil Engineering Indian Institute of Technology RoorkeeRoorkee 247667India Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

Rutting is the major distress mode in flexible pavements occurring due to the repeated movement of traffic loading. Deformation in the pavements comprise of both recoverable(elastic) and irrecoverable(plastic) part. Overall deformation occurring in the flexible pavement system due to continuous vehicular movement is contributed from all the components of pavement. A number of empirical models have been proposed by several researchers for analysis and prediction of accumulated rutting in different components of pavement. The accumulated permanent strain has been expressed as the function of the number of load applications and deviator stress applications in most of the models proposed;however, factors such as stress state, moisture content, material type and environmental conditions also impose a significant influence on the permanent deformation characteristics of pavement materials under cyclic loading. In this article, a comprehensive review has been carried out covering every aspect of deformation related to distress occurring in pavements. Important rut models, modeling approaches and modern concepts in the rutting analysis of pavement structures have been presented. In addition to review, fallacy existing in the current design practices related to adaptation of stiffness parameters and negligence of shear strength aspect of subgrade soil has been also presented with the support of literatures.

关键词： Road engineering Permanent deformation Rutting models Resilient modulus Shear strength

Current efficiency in electro-winning of lanthanum and cerium metals from molten chloride electrolytes

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2013年第3期32卷 305-311页

作者： Deepak kumar sahoo Harvinderpal Singh Nagaiyar Krishnamurthy Rare Earths Development Section Bhabha Atomic Research Centre Fusion Reactor Materials Section Bhabha Atomic Research Centre

The objective of this study is to prepare lan- thanum and cerium metals by fused salt electrolysis of their anhydrous chloride in molten media such as LiCl-KCl, NaCl-KCl, KCl, NaCl, and LiCl and to characterize the metal deposit by X-ray diffraction, energy dispersive X-ray fluorescence, and inductive coupled plasma-atomic emis- sion spectroscopy. Deposit metal of purity more than 99 % was obtained in each of the experiments. The entire process starting from preparation of anhydrous lanthanum/cerium chloride to electrolysis yielding of metal deposits has been described. The effect of process parameters such as tem- perature, electrolyte composition, and current density on the current efficiency was studied. All these parameters were varied to get the highest current efficiency and metal yield. The major non-rare earth impurities with the deposit are found to be Fe, Cr, and Ni along with - 1× 10^-3 of total gaseous impurities.

关键词： Fused salt electrolysis Current density Current efficiency Rare earths

Effect of lanthanum,neodymium on piezoelectric,dielectric and ferroelectric properties of PZT

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2013年第1期2卷 37-41页

作者： Benudhar sahoo Prasanta kumar PANDA Materials Science Division CSIR-National Aerospace LaboratoriesKodihalliP.B.No.1779Bangalore 560017India

The effect of La^(3+)and Nd^(3+)on piezoelectric,dielectric and ferroelectric properties of PZT(Pb(Zr_(0.53)Ti_(0.47))O_(3))was *** powders were prepared by“wet-chemical”route followed by calcination at 800℃for 4 *** analysis of the calcined powders confirms the tetragonal phase in the undoped PZT,which gradually decreases with the dopant concentration and the appearance of rhombohedral phase *** study of sintered pellets reveals the decrease in grain size with the increase in dopant concentration beyond 0.02 mol Nd^(3+)and 0.03 mol La^(3+)*** piezoelectric constant(d_(33))and dielectric properties were maximum for 0.02 mol Nd^(3+)and 0.03 mol La^(3+)*** remnant polarization of La^(3+)-doped sample was higher than Nd^(3+)-doped sample,and the sample with combined dopants shows intermediate remnant polarization(P_(r)).Based on the above study,it is concluded that La^(3+)is more effective than Nd^(3+),including in a mixture of La^(3+)and Nd^(3+)dopants.

关键词： lead zirconate titanate wet-chemical piezoelectric dielectric ferroelectric

Synthesis and characterization of manganese tetroxide(Mn_(3)O_(4))nanofibers by electrospinning technique

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 Advanced Ceramics 2013年第1期2卷 26-30页

作者： Benudhar sahoo Prasanta kumar PANDA Materials Science Division CSIR-National Aerospace LaboratoriesKodihalliP.B.No.1779Bangalore 560017India

Manganese tetroxide(Mn_(3)O_(4))nanofibers were prepared by electrospinning homogeneous viscous solution of 20 wt%,28 wt%and 36 wt%manganese acetate in poly vinyl alcohol(PVA)and calcining the nanofibers at 1000℃for 2 *** was carried out at 9 kV DC with tip to collector distance(TCD)of 7 *** gravimetric analysis(TGA)of the fibers indicates the pure phase of manganese oxide above 500℃.XRD analysis of calcined(at 1000℃)nanofibers indicates the formation of phase-pure tetragonal Mn_(3)O_(4).Scanning electron microscopy(SEM)studies show the fibers cylindrical with the diameters in the range of 100-600 nm and aspect ratio>*** general,the average diameter of the green fibers decreases with the increase in manganese acetate *** diameter of calcined nanofibers is reduced by 34%.

关键词： electrospinning manganese tetroxide poly vinyl alcohol nanofiber

Impact of Cumulative Exposure to Circulating Ovarian Sex Hormones on Increasing the Risk of Hormone Receptor-Positive Breast Cancer

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 Bio-X Research 2024年第1期7卷 36-43页

作者： Swati Sucharita Mohanty Sumit Subhadarshi Mohanty Soumya Surath Panda Chita Ranjan sahoo Prafulla kumar Mohanty Rabindra Nath Padhy Siksha O Anusandhan University Institute of Medical Sciences and SUM Hospital BhubaneswarOdishaIndia Regional Medical Research Centre Bhubaneswar BhubaneswarOdishaIndia Khallikote Unitary University BrahmapurOdishaIndia

There were 2.3 million new cases of breast cancer registered in 2020,establishing it as the world’s leading *** regular exposure of breast cells to circulating ovarian sex hormones may contribute to cancer growth at all stages.A literature review was performed by downloading research articles from PubMed Central,with keywords such as breast cancer,hormone exposure in breast cancer,estrogen/progesterone exposure in breast cancer,and breast cancer risk *** breast cancer is a hormone-related disease,several factors that influence hormonal conditions or are indicators of alterations in hormonal conditions have been linked with the risk for breast ***,an elevated risk for breast cancer has been related to reproductive history and exogenous estrogen exposure because they may amplify lifetime estrogen *** these factors address the total cumulative exposure to circulating ovarian sex hormones that a female is vulnerable to in her lifetime.A healthy lifestyle,a more extended breastfeeding period,and regular physical activity may help lower one’s *** review summarizes the factors that increase the risk of estrogen/progesterone(hormone receptor)receptor-positive breast cancer due to overall cumulative estrogen exposure,with an understanding of estrogen biosynthesis mechanisms and estrogen receptor signaling.

关键词： alterations elevated exposure

Performance assessment of aged binder rejuvenated with Polanga oil

在线全文

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2019年第6期6卷 608-620页

作者： Sujit kumar Pradhan Umesh Chandra sahoo School of Infrastructure Indian Institute of Technology BhubaneswarOdisha 752050India

Presently,there is a necessity of increasing the reclaimed asphalt pavement(RAP)content in recycling of asphalt pavements to save material cost,preserve energy and protect the environment and efforts are being made to utilize 100%RAP in the *** binder is usually stiff due to oxidation and loss of *** addition of high amount of RAP to the asphalt mix,may make it prone to fatigue *** to this reason,rejuvenators are added to restore some of the physical and chemical properties for desired performance of the *** this study,a locally available non-edible oil known as Polanga oil(biological name:Calophyllum inophyllum)has been explored as rejuvenator to study its effect on performance of the aged *** binder prepared in the laboratory using the Pressure Aging Vessel(PAV)and binder extracted from the RAP collected from a nearby source were used in this study for *** binder and RAP binder mixed with the rejuvenator at varying *** rheological characterizations in terms of flow,rutting,fatigue and creep recovery of rejuvenated PAV aged&RAP binders were carried out using a dynamic shear rheometer(DSR)to determine the optimum dosage of the *** was observed that,5 percent of Polanga oil is able to divulge the desirable rheological properties of the rejuvenated binder.

关键词： Virgin bitumen Reclaimed asphalt pavement Rejuvenator Polanga oil Aged bitumen Rheology

Phytohormones and their metabolic engineering for abiotic stress tolerance in crop plants

在线全文

学校读者我要写书评

暂无评论

The Crop Journal 2016年第3期4卷 162-176页

作者： Shabir H.Wani Vinay kumar Varsha Shriram saroj kumar Sah Division of Genetics and Plant Breeding Faculty of Agriculture WADURASher-e-Kashmir University of Agricultural Sciences and Technology Department of Biotechnology Modern College of ArtsScience and CommerceS.P.Pune University Department of Botany Prof.Ramkrishna More CollegeS.P.Pune University Department of Biochemistry Molecular BiologyEntomology and Plant PathologyMississippi State University

Abiotic stresses including drought,salinity,heat,cold,flooding,and ultraviolet radiation causes crop losses *** recent times,preventing these crop losses and producing more food and feed to meet the demands of ever-increasing human populations have gained unprecedented ***,the proportion of agricultural lands facing multiple abiotic stresses is expected only to rise under a changing global climate fueled by anthropogenic *** the mechanisms developed and deployed by plants to counteract abiotic stresses and maintain their growth and survival under harsh conditions thus holds great *** investigations have shown that phytohormones,including the classical auxins,cytokinins,ethylene,and gibberellins,and newer members including brassinosteroids,jasmonates,and strigolactones may prove to be important metabolic engineering targets for producing abiotic stress-tolerant crop *** this review,we summarize and critically assess the roles that phytohormones play in plant growth and development and abiotic stress tolerance,besides their engineering for conferring abiotic stress tolerance in transgenic *** also describe recent successes in identifying the roles of phytohormones under stressful *** conclude by describing the recent progress and future prospects including limitations and challenges of phytohormone engineering for inducing abiotic stress tolerance in crop plants.

关键词： Phytohormones Abiotic stress Metabolic engineering Plant stresses

Integration of silicon nanowires in solar cell structure for efficiencyenhancement: A review

在线全文

学校读者我要写书评

暂无评论

Journal of Materiomics 2019年第1期5卷 34-48页

作者： Mihir kumar sahoo Paresh Kale Department of Electrical Engineering NIT RourkelaOdisha769008India

Silicon nanowires (SiNWs) are a one-dimensional semiconductor, which shows promising applications indistinct areas such as photocatalysis, lithium-ion batteries, gas sensors, medical diagnostics, drug delivery,and solar cell. From an implementation point of view, SiNWs are fabricated using either a topdownor bottom-up approach, and SiNWs are both optically and electronically active. SiNWs enhancesthe efficiency of the solar cell due to better electronic, optical, and physical properties that can becontrolled by tuning the physical dimensions of SiNWs. The SiNWs shows an inherent capability to beutilized in radial or coaxial p-n junction solar cells, to stipulate orthogonal photon absorption, antireflection,and enhanced carrier collection. This paper reviews property-control of SiNWs, theirvarious types of incorporation in a solar cell, and the reasons behind enhanced efficiency.

关键词： Optical Electronic and physical properties Axial solar cell Radial solar cell Anti-reflection coating Silicon nanowires solar cell

Topical delivery of acetazolamide by encapsulating in mucoadhesive nanoparticles

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

Asian Journal of Pharmaceutical Sciences 2017年第6期12卷 550-557页

作者： Satish Manchanda Pravat kumar sahoo Delhi Institute of Pharmaceutical Sciences and Research (DIPSAR)

The intent of this study was to provide topical delivery of acetazolamide by preparing chitosan-STPP (sodium tripolyphosphate) nanoparticles of acetazolamide and evaluate the particle size, zeta potential, drug entrapment, particle morphology;in vitro drug release and in vivo efficacy. The particles showed sustained in vitro drug release which followed the Higuchi kinetic model. The results indicate that the nanoparticles released the drug by a combination of dissolution and diffusion. The optimised formulation was having particle size 188.46 ± 8.53 nm and zeta potential + 36.86 ± 0.70 mV. The particles were spherical with a polydispersity index of 0.22 ± 0.00. Powder X-ray diffraction and differential scanning calorimetry indicated diminished crystallinity of drug in the nanoparticle formulation. In the in vitro permeation study, the nanoparticle formulation showed elevated permeation as compared to that of drug solution with negative signs of corneal damage. In vitro mucoadhesion studies showed 90.34 ± 1.12% mucoadhesion. The in vivo studies involving ocular hypotensive activity in rabbits revealed significantly higher hypotensive activity (P < 0.05) as compared with plain drug solution with no signs of ocular irritation. The stability studies revealed that formulation was quite stable.

关键词： Acetazolamide Chitosan STPP Ocular hypertension Mucoadhesion