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A Limited Area Model for Monsoon Prediction

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Advances in Atmospheric Sciences 1990年第1期7卷 111-126页

作者： S.S.singh S.S Vaidya E.n.Rajagopal Indian Instituteof Tropical Meteorology Pune-411005 IndiaIndian Instituteof Tropical Meteorology Pune-411005 IndiaIndian Instituteof Tropical Meteorology Pune-411005 India

A six level regional primitive equation model has been formulated and tested for monsoon prediction. The model uses dynamic normal mode initialization scheme for obtaining initial balance. The physical processes included are: the large scale condensation, the Kuo type of cumulus convection, the surface friction, the sensible heat supply and evaporation over the sea. The actual smooth orography is included. The model has been integrated for 48 hrs using input of 7 July and 8 August 1979 when the domain of integration was dominated by an intense monsoon depression. In order to investigate the model simulation of formative stage of the depression, the model was also integrated using input of 4 July ***, the envelope orography has been constructed and included in the model for investigating its effects on the monsoon prediction. Results of the model forecast are presented and discussed.

关键词： GMT mode

Microstructural analysis and hot corrosion behavior of HVOF-sprayed ni–22Cr–10Al–1Y and ni–22Cr–10Al–1Y–SiC(n) coatings on ASTM-SA213-T22 steel

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 401-416页

作者： Gurmail singh niraj Bala Vikas Chawla Department of Mechanical Engineering IKGPTUJalandhar 144603PunjabIndia Department of Aerospace Engineering Chandigarh UniversityGharuan 140413PunjabIndia Department of Mechanical Engineering BBSBECFatehgarh Sahib 140407PunjabIndia

The present paper deals with the investigation of microstructure and high-temperature hot corrosion behavior of high-velocity oxy fuel(HVOF)-produced coatings. Two powder coating compositions, namely, ni22Cr10Al1Y alloy powder and ni22Cr10Al1Y(80 wt%;microsized)–silicon carbide(SiC)(20 wt%;nano(n)) powder, were deposited on a T-22 boiler tube steel. The hot corrosion behavior of bare and coated steels was tested at 900°C for 50 cycles in na2SO4–60 wt%V2O5 molten-salt environment. The kinetics of corrosion was established with weight change measurements after each cycle. The microporosity and microhardness of the as-coated samples have been reported. The X-ray diffraction,field emission-scanning electron microscopy/energy dispersive spectroscopy, and X-ray mapping characterization techniques have been utilized for structural analysis of the as-coated and hot-corroded samples. The results showed that both coatings were deposited with a porosity less than2%. Both coated samples revealed the development of harder surfaces than the substrate. During hot corrosion testing, the bare T22 steel showed an accelerated corrosion in comparison with its coated counterparts. The HVOF-sprayed coatings were befitted effectively by maintaining their adherence during testing. The ni22Cr10Al1Y–20 wt%SiC(n) composite coating was more effective than the ni–22Cr–10Al–1Y coating against corrosion in the high-temperature fluxing process.

关键词： high-velocity oxy fuel thermal spray hot corrosion oxide scale nano-structured coating

有FACTS装置的电力系统在市场环境下的最优调度

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电力系统自动化 2001年第4期25卷 20-24,44页

作者： S.n.singh A.K.David 香港理工大学电机工程系中国香港

随着电力工业重构的不断深入 ,转运业务需求的增加要求系统提供更高的输送能力。FACTS技术的应用能够提高系统的输电能力、降低网损、改善系统的稳定性、降低电能成本 ,促使电能交易顺利完成。依据有功性能指标 ,文中提出了 FACTS装置... 详细信息

随着电力工业重构的不断深入 ,转运业务需求的增加要求系统提供更高的输送能力。FACTS技术的应用能够提高系统的输电能力、降低网损、改善系统的稳定性、降低电能成本 ,促使电能交易顺利完成。依据有功性能指标 ,文中提出了 FACTS装置的优化配置方法 ,并通过解最优潮流问题得到 FACTS装置的可控参数值 ,同时讨论了 FACTS装置对系统实时电价的影响。用IEEE— 1 4节点算例验证了所提算法的有效性。

关键词：电力系统最优调度 FACTS装置市场环境

Teratogenicity Studies of a new Potent Tetanus Vaccine in Rabbit (Oryctolagus cuniculus)

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Biomedical and Environmental Sciences 1991年第3期4卷 327-331页

作者： n.SETHI R.K.SRIVASTAVA R.K.singh Division of Toxicology Central Drug Research Institute Lucknow 226001 IndiaDivision of Toxicology Central Drug Research Institute Lucknow 226001 IndiaDivision of Toxicology Central Drug Research Institute Lucknow 226001 India

Glaxo Laboratories, Bombay, have prepared a potent tetanus vaccine of 250 Lf as a substitute of the previous 5 Lf tetanus vaccine. The safety evaluation of the vaccine has been reported, but the teratogenic potential was not studied. In the experiment reported herein we have studied the teratogenic action of the vaccine in the progeny of rabbits. no congenital anomalies were observed.

关键词： In Oryctolagus cuniculus Teratogenicity Studies of a new Potent Tetanus Vaccine in Rabbit

Site-Specific nitrogen Management in Dry Direct-Seeded Rice Using Chlorophyll Meter and Leaf Colour Chart

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Pedosphere 2015年第1期25卷 72-81页

作者： Ali Mohamed ALI Harmit singh THInD Sandeep SHARMA YADVInDER-singh Department of Soil Science Punjab Agricultural University Department of Soil Fertility and Microbiology Desert Research Centre

The need to maintain high rice yields and improve fertilizer nitrogen(n)-use efficiency has fueled the use of tools such as leaf colour chart(LCC) and chlorophyll meter(SPAD meter) in managing fertilizer n based on colour of the leaf. Field experiments were conducted during 2011 to 2013 at Ludhiana, India to assess the need for basal n application and to establish critical threshold values of leaf greenness as measured by LCC and SPAD meter for formulating strategies for in-season management of fertilizer n in dry direct-seeded rice(DDSR). Avoiding application of n at sowing did not adversely affect rice grain yield, indicating that basal n application in DDSR was not necessary and might lead to reduced n-use efficiency. Monitoring n uptake rate during the growing season of DDSR suggested that n uptake rate peaked at the two growth stages: maximum tillering(42 to 56 days after sowing(DAS))and panicle initiation stages(70 to 84 DAS). Using the Cate-nelson procedure, critical LCC and SPAD meter values for fertilizer n application worked out to be 4 and 37, respectively. Real-time fertilizer n management strategy based on applying 30 kg n ha-1whenever SPAD meter or LCC readings fell below the critical values maintained optimum rice yields along with higher n-use efficiency than that observed by following blanket recommendation for fertilizer n in the region. The fixed-time variable-dose strategy consisted of applying prescriptive doses of 20 kg n ha-1at 14 DAS and 30 kg n ha-1at 28 DAS and corrective doses of 30, 40 or 50 kg n ha-1at 49 and 70 DAS depending upon LCC shade to be ≥ 4, 4–3.5, or nd SPAD meter readings to be ≥ 40, 40–35, orn optimal rice yield along with higher n-use efficiency as compared to the blanket recommendation. This study revealed that in DDSR, fertilizer n could be managed more efficiently using the tools of LCC and SPAD meter than the current blanket recommendation.

关键词： basal n application critical value grain yield leaf greenness n-use efficiency

Bio-amelioration of alkali soils through agroforestry systems in central Indo-Gangetic plains of India

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Journal of Forestry Research 2014年第4期25卷 887-896页

作者： Y.P.singh Gurbachan singh D.K.Sharma Central Soil Salinity Research Institute Regional Research StationLucknow (U.P.) 226005 India Indian Council of Agricultural Research New Delhi 110001 India Central Soil Salinity Research Institute Karnal Haryana 132001 India

A long-term field study was initiated during 1995 at Central Soil Salinity Research Institute, Regional Research Station, Lucknow （26047＇58＂ n and 80°46＇24＂ E） to analyze the effect of agroforestry systems on amelioration of alkali soils. Three agroforestry systems （pas- toral, silvipastoral and silvicultural） were compared with the control where no agroforestry system was introduced. Tree-based silvicultural and silvipastoral systems were characterized by tree species Prosopis juliflora and Acacia nilotica along with grass species Leptochloafusca, Panicum maximum, Trifolium alexandrium and Chloris gayana. Growth of ten-year-old Prosopis juliflora and Acacia nilotica planted in combi- nation with grasses was significantly higher over the silviculture system with the same species. Tree biomass yields of P. juliflora （77.20 t·ha-1） and A. nilotica （63.20 t·ha-1） planted under silvipastoral system were significantly higher than the sole plantation of （64.50 t·ha-1 and 52.75 t·ha-1）. Fodder yield under the pastoral system was significantly higher than the silvipastoral system during initial years but it was at par with that of silvipastoral systems after eight years of plantation. The microbial biomass carbon in the soils of silvipastoral systems was significantly higher than in soils under sole plantation of trees and control systems. The Prosopis-based silvipastoral system proved more effective in reduc- ing soil pH, displacing na＋ from the exchange complex, increasing or- ganic carbon and available n, P and K. Improvement in soil physical properties such as bulk density, porosity, soil moisture and infiltration rate was higher in the Prosopis-based silvipastoral system than in the silviculture system or control On the basis of biomass production and improvement in soil health due to tree ＋ grass systems, silvipastoral agroforestry system could be adopted for sustainable reclamation ofhighly alkali soils.

关键词： agroforcstry systems alkali soils biomass production mi-crobial biomass soil amelioration

Efficient One-Pot Access to 2,9-Dihydrothiopyrano[2,3-b]indole Scaffolds Showing Large Stokes Shifts

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Chinese Journal of Chemistry 2015年第11期33卷 1244-1250页

作者： Shivendra singh Sampak Samanta Department of Chemistry Indian Institute of Technology Indore Indore 452017 India

A simple, mild and efficient one-pot approach for the construction of 2-aryl-3-nitro-2,9-dihydrothiopyrano- [2,3-b]indole derivatives has been realized in CH2C12 medium at ambient temperature via three-component tandem reaction of n-protected-2-chloro-3-formylindoles, sodium hydrosulfide and β-substituted nitroolefins/δ-substituted nitrodienes using DABCO （10 mol%） as an organocatalyst, followed by dehydration in the presence of activated molecular sieves （4 A）. The significant advantages of this protocol are simple operation, shorter reaction time, high atom economy, good to high yields （73%-89%） and wider substrate scope. In addition, all the synthesized com- pounds have shown the large positive Stokes shift values （5632-6081 cm ^-1）.

关键词： one-pot MCR 2,9-dihydrothiopyrano[2,3-b]indole organocatalysis molecular sieves large Stokes shifts

near-saturated soil hydraulic conductivity and pore characteristics as influenced by conventional and conservation tillage practices in north-West Himalayan region,India

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International Soil and Water Conservation Research 2021年第2期9卷 249-259页

作者： Deepak singh Alok Kumar Mishra Sridhar Patra Sankar Mariappan nisha singh ICAR-Indian Institute of Soil and Water Conservation Dehradun248195UttarakhandIndia Sam Higginbottom University of Agriculture Technology and SciencesPrayagraj211007U.PIndia Hemvati nandan Bahuguna Garhwal University(A Central University) Srinagar(Garhwal)246174UttarakhandIndia

Tillage plays an important role in modifying soil hydraulic *** objective of the present study was to evaluate the effect of conservation tillage practices in a maize-wheat cropping system on nearsaturated soil hydraulic properties and pore characteristics in the north-West Himalayan region,*** treatments *** tillage(CT),minimum tillage(MT),and zero tillage(ZT)were evaluated in terms of field saturated hydraulic conductivity(ks),unsaturated hydraulic conductivity k(h),the inverse of capillary length(a),flow-weighted mean pore radius(r0),numbers of pores per square meter(n0)and water-conducting macroporosity(Ɛ).The above hydraulic conductivity and pore characteristics were derived from steady-state water flux(q)measured using hood infiltrometer at 0,1,and3 cm pressure head for each treatment after seven years of establishment of this tillage *** revealed significantly(pndƐin ZT as compared with *** had intermediate *** a values suggested a greater gravity-dominated flow under ZT and MT as compared with *** of r0 values indicated better connectivity of pores in ZT and MT as compared with *** flow suggested that on average pore radii,>0.50 mm conducted about 63.60,68.01,and 75.97%of total flow(at 0 cm pressure head)in the corresponding water-conducting macroporosity of 0.00030,0.00044,and 0.00069%of soil volume under CT,MT,and ZT,***,zero-tillage based agriculture system was found to improve near-saturated soil hydraulic properties.

关键词： near-saturated hydraulic conductivity Macropores Tillage Flow weighted mean pore radius Water-conducting macroporosity

Cosmological Models with Time Dependent G and A Coupling Scalars

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Chinese Physics Letters 2009年第6期26卷 45-47页

作者： n. Ibotombi singh S. Kiranmla Chanu S. Surendra singh Department of Mathematics Manipur University Canchipur-795003 Manipur India

A cosmologicM model in which the universe has its critical density and gravitational constants generalized as coupling scalars in Einstein＇s theory is considered. A general method of solving the field equations is given. An exact solution for matter distribution in cosmological models satisfying G = G0（ R/ R0）^n is presented. Corresponding physical interpretations of the cosmological solutions are also discussed.

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