检索结果-南通市图书馆

Microstructural relation of macerals with mineral matter in coals from Ib valley and Umaria, Son-Mahanadi basin, India

在线全文

学校读者我要写书评

暂无评论

International Journal of Coal Science & Technology 2017年第2期4卷 191-197页

作者： vivek Mishra K. N. Singh CSIR - National Metallurgical Laboratory Jamshedpur 831007 India School of Studies in Earth Science Vikram UniversityUjjain 456010 India

Coal petrology provides significant inputs for the industrial utilisation of coal and for broad understanding the coal formation and diagenesis. The present paper entails the results of the investigations carded out on the selected coal samples, from Ib valley and Umaria coalfield, using scanning electron microscope （SEM） and X-ray diffraction （XRD） to study the surface microstructures and minerals present in them and the relationship of the finely dispersed mineral matter with the organic constituents. This would further help in evaluating the distribution and chemical character of the mineral matter occurring within the maceral types. Ib valley and Umaria coals are typical Indian （Lower Gondwana） non-coking coals and only scanty data is available on SEM study of these coals. Under SEM examination, it manifests that, the mineral matters of these coal occur as deep intergrowth, massive impregnation, superficial mounting, filling and depletion of micropores, mechanical cavity filling and fusinitic cavity filling.

关键词： Coal SEM XRD Umaria coal Ib valley coal India

Optimal generation mix for frequency response adequacy in future power system

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy and Built Environment 2021年第3期2卷 243-250页

作者： vivek Prakash Kailash Chand Sharma Rohit Bhakar School of Automation Banasthali VidyapithRajasthanIndia Department of Electrical Engineering NIT JalandharIndia Department of Electrical Engineering Malaviya National Institute of TechnologyJaipurIndia

Strict enforcement of government policies to integrate high generation share from renewable energy sources(RES)like wind and PV would create inevitable operational challenges for the utilities to deliver Frequency Response(FR)*** RES generation characteristics would worsen the situation for SO,to detain initial frequency deviation following the largest generation *** necessitates investigation of optimal generator combination for securing PFR adequacy with simultaneous characterization of *** this regard,this paper proposes a novel Modified Interval(MI)based optimal generation mix formulation for operation cost minimization and FR *** uncertainty is characterised by forecasted upper and lower bound,while hourly ramp needs are based on the net load *** model is assessed on one area IEEE reliability test *** of change of frequency(ROCOF)and frequency deviation are considered as network security limits to obtain optimal generation *** obtained provide,overall cost performance,PFR and optimal generation mix,without violating system security *** model would certainly assist SO,to enhance system’s inertia and PFR adequacy at short-term system operations and could be extended for long-term planning framework.

关键词： Frequency response Generation mix Inertial response Net load Primary frequency response System security Unit commitment

Wear and Friction Properties of Electrodeposited Ni-Based Coatings Subject to Nano-enhanced Lubricant and Composite Coating

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 902-910页

作者： Rizwan Bajwa Zulfiqar Khan H.Nazir vivek Chacko Adil Saeed NanoCorr Energy and Modelling Research GroupBournemouth University

This paper presents research findings on the tribological performance of electrodeposited coatings subject to nano-lubricants with the addition of nano-Al2O3 and graphene and Ni/nano-Al2O3 composite coatings. Electrodeposited coatings were produced by using a pulse electrodeposition method. Tribological experiments were conducted by using a linear reciprocating ball on fiat sliding tribometer. Experimental results confirmed that the wear and friction resistance properties were significantly enhanced by doping of nano-effects in the lubricating oil and composite coating. The addition of Al2O3 nanoparticles in the lubricating oil showed the best tribological properties, followed by Ni-Al2O3 composite coatings and nano-oil with graphene. The surface morphology and microstructure of electrodeposited coatings were examined by scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction. The wear mechanisms of these coatings subjected to tribological testing were investigated by post-test surface analyses. This research provides a novel approach to design durable nano-coatings for tribological applications in various industries such as automotive, aerospace, locomotive and renewable energy technologies.

关键词： Tribology Nanoparticles Graphene Nano-additives Nano-coatings

Multi-scale characterization and simulation of impact welding between immiscible Mg/steel alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第24期59卷 149-163页

作者： Jiahao Cheng Xiaohua Hu Xin Sun Anupam vivek Glenn Daehn David Cullen Oak Ridge National Laboratory 1 Bethel Valley RoadOak RidgeTN37831USA Department of Materials Science Engineering Ohio State University116 W Nineteenth AveColumbusOH43210USA

Vaporizing foil actuator spot welding method is used in this paper to join magnesium alloy AZ31 and uncoated high-strength steel DP590,which are typically considered as un-weldable due to their high physical property disparities,low mutual solubility,and the lack of any intermetallic *** results from scanning electron microscopy(SEM)and high-resolution transmission electron microscopy(HRTEM)of the weld interface indicate that the impact creates an Mg nanocrystalline interlayer with abundant Fe *** interlayer exhibits intact bonding with both DP590 and AZ31 *** investigate the fundamental bond formation mechanisms at the interface,a finite element(FE)-based process simulation is first performed to calculate the local temperature and deformation at the interface under the given macroscopic experimental *** the FE results at the interface as inputs,molecular dynamics(MD)simulations are conducted to study the interlayer formation at the Mg/Fe interface during the impact and *** results found a high velocity shearing-induced mechanical mixing mechanism that mixes Mg/Fe atoms at the interface and creates the interlayer,leading to the metallurgical bond between Mg/steel alloys.

关键词： Impact welding Immiscible alloys Interface microstructure Finite element analysis Molecular dynamics simulation

Endothelial dysfunction in the kidney transplant population:Current evidence and management strategies

在线全文

学校读者我要写书评

暂无评论

World Journal of Transplantation 2025年第1期15卷 24-43页

作者： Arun Prabhahar Akshey Batta Juniali Hatwal vivek Kumar Raja Ramachandran Akash Batta Department of Telemedicine(Internal Medicine and Nephrology) Post Graduate Institute of Medical Education and ResearchChandigarh 160012India Department of Urology and Renal Transplant Neelam HospitalRajpura 140401PunjabIndia Department of Internal Medicine Post Graduate Institute of Medical Education and ResearchChandigarh 160012India Department of Nephrology Post Graduate Institute of Medical Education and ResearchChandigarh 160012India Department of Cardiology Dayanand Medical College and HospitalLudhiana 141001PunjabIndia

The endothelium modulates vascular homeostasis owing to a variety of vasoconstrictors and *** dysfunction(ED),characterized by impaired vasodilation,inflammation,and thrombosis,triggers future cardiovascular(CV)*** kidney disease,a state of chronic inflammation caused by oxidative stress,metabolic abnormalities,infection,and uremic toxins damages the *** is also associated with a decline in estimated glomerular filtration *** kidney transplantation,endothelial functions undergo immediate but partial restoration,promising graft longevity and enhanced CV ***,the anticipated CV outcomes do not happen due to various transplant-related and unrelated risk factors for ED,culminating in poor CV health and graft *** in kidney transplant recipients is an underrecognized and poorly studied *** diseases are the leading cause of death among kidney transplant candidates with functioning *** contributes to the pathogenesis of many of the CV *** biomarkers and vasoreactivity tests are available to study endothelial *** an increasing number of transplants happening every year,and improved graft rejection rates due to the availability of effective immunosuppressants,the focus has now shifted to endothelial protection for the prevention,early recognition,and treatment of CV diseases.

关键词： Endothelial dysfunction Endothelium Cardiovascular disease Kidney transplantation Chronic kidney disease Nitric oxide Flow-mediated dilatation Nitro-glycerine-mediated dilatation Biomarkers

China's Economic Growth:International Spillovers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China & World Economy 2011年第5期19卷 31-46页

作者： vivek Arora Athanasios Vamvakidis Assistant Director Asia-Pacific Departmcnt IMFWashingtonDCUSA Deputy Division Chief Stratcgy Policy and Review DepartmentIMFWashingtonDCUSA

China＇s economic development since 1978 is one of the most significant events in recent history. Many aspects of this development have been extensively analyzed in the published literature. However, the implications of China ＇s growth for other countries have been relatively neglected. The present paper attempts to fill this gap in the literature. The paper first presents some facts on China＇s role in the world economy, and then measures the impact of China＇s growth on growth in the rest of the world in both the short term and the long term. Short-run estimates based on vector autoregression and error correction models suggest that spillover effects of China＇s growth have increased in recent decades, Long- term spillover effects, estimated through growth regressions based on panel data, are also significant and have extended in recent decades beyond Asia. The estimates are robust to the effects of global and regional shocks, changes in model specification, and sample period.

关键词： China growth spiUovers

Comparative studies on numerical sensitivity of different scenarios of enhanced oil recovery by water-alternating-gas(CO_(2))injection

在线全文

学校读者我要写书评

暂无评论

Petroleum Research 2023年第4期8卷 505-513页

作者： Saddam Mohammed Mohammed Nasser Achinta Bera vivek Ramalingam School of Energy Technology Pandit Deendayal Energy UniversityGandhinagarGujarat382007India

Enhanced oil recovery by CO_(2) injection technology(CO_(2)-EOR)plays a crucial role in enhancing oil production and the permanent sequestration of anthropogenic CO_(2) in depleted oil ***,the availability of CO_(2) in oil field locations and its mobility in contrast with reservoir fluids are prime challenges in CO_(2)-*** cost of CO_(2) and its availability at the oil fields has prompted investigations on efficient injection of CO_(2) at the fields to achieve the best sweep efficiency *** strategies such as water-alternating-gas(WAG),simultaneous vertical and horizontal WAG,simultaneous water injection into the aquifer and vertical WAG,water and gas injection simultaneously but separately(SS-WAG),and water and gas injection simultaneously but not separately(SNS-WAG)play a significant role,as well as the purity of CO_(2).In this work,the significance of the above criteria was investigated indi-vidually and in *** coupled sequence of injection rate,soaking time,WAG ratio,and purity of injected CO_(2) for enhancement of oil production were delineated.A realistic reservoir simulation model conceptualizing the CO_(2)-EOR system with five spot injection patterns was developed by the company *** history-matched model that was developed was used to investigate the sensitivity of the coupled effects to the criteria listed above on oil *** investigations quantitatively emphasized that purity and soaking time of CO_(2) have an inverse effect in the oil production rate and that SNS-WAG resulted in a better oil production rate than SS-WAG.

关键词： Water-alternating-gas Enhanced oil recovery Sensitivityanalysis Modelingand simulation Simultaneouslybut not separately water-alternating-gas(SS-WAG) Simultaneously pressure maintenance and WAG

Capillary electrophoresis methods for impurity profiling of drugs:A review of the past decade

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 Pharmaceutical Analysis 2022年第1期12卷 15-28页

作者： Mansi Shah Nrupesh Patel Nagja Tripathi vivek K.Vyas Department of Pharmaceutical Analysis Institute of PharmacyNirma UniversityAhmedabad382481GujaratIndia Department of Pharmacognosy Institute of PharmacyNirma UniversityAhmedabad382481GujaratIndia Department of Pharmaceutical Chemistry Institute of PharmacyNirma UniversityAhmedabad382481GujaratIndia

Capillary electrophoresis(CE)is widely used for the impurity profiling of drugs that contain stereochemical centers in their structures,analysis of biomolecules,and characterization of ***,CE is the method of choice for the analysis of foodstuffs and the determination of *** article discusses the general theory and instrumentation of CE as well as the classification of various CE *** also presents an overview of research on the applications of different CE techniques in the impurity profiling of drugs in the past *** review briefly presents a comparison between CE and liquid chromatography methods and highlights the strengths of CE using drug compounds as *** review will help scientists,fellow researchers,and students to understand the applications of CE techniques in the impurity profiling of drugs.

关键词： Capillary electrophoresis Impurities Impurity profiling Drugs

Utility of starchy,lignocellulosics and cellulosics hydrolysates on cellulase production under liquid state fermentation

在线全文

学校读者我要写书评

暂无评论

Waste Disposal and Sustainable Energy 2019年第4期1卷 289-299页

作者： Nitin Verma vivek Kumar M.C.Bansal Department of Paper Technology Indian Institute of TechnologyRoorkee Saharanpur CampusSaharanpurUttar Pradesh 247001India

Starch is one of the most abundant renewable carbohydrate reserves of higher *** can be used to produce many valuable food products in the food processing ***,starch is also used as an important feedstock in the fermentation industry to produce value-added *** materials such as agriculture and forestry wastes are considered as a renewable feedstock for bioenergy production through a biochemical conversion *** lignocellulosic biomass into fuels and chemicals entail a physicochemical pretreatment of the biomass,followed by enzymatic hydrolysis of the polysaccharide components such as cellulose and hemicellulose into monomeric *** sugars can then be further fermented into other desired compounds of *** the deconstruction processes,various inhibitory compounds are released due to the partial over-degradation of lignocellulose biomass,which inhibits the cell growth and metabolic capacity of fermenting *** materials such as waste paper in large quantities can also be used as potentially cheap feedstock for sustainable production of value-added *** present investigation is mainly focused on the utility of starchy hydrolysates(wheat,potato,and rice)and lignocellulosics hydrolysates(bagasse and wheat straw)in cellulase production under liquid state *** also depicts the potential of cellulosic hydrolysate(waste newspaper)in product formation.

关键词： Starch hydrolysate Bagasse hydrolysate Wheat straw hydrolysate Waste newspaper hydrolysate Cellulases