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A proposed surface resistance model for the Penman-Monteith formula to estimate evapotranspiration in a solar greenhouse

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Journal of Arid Land 2017年第4期9卷 530-546页

作者： GONG Xuewen LIU Hao sUN Jingsheng GAO Yang ZHANG Xiaoxian shiva k jha ZHANG Hao MA Xiaojian WANG Wanning key Laboratory of Crop Water Use and Regulation Ministry of AgricultureFarmland Irrigation Research InstituteChineseAcademy of Agricultural SciencesXinxiang 453003China Graduate school of Chinese Academy of Agricultural sciences Beijing 100081China Department of sustainable soils and Grassland systems Rothamsted ResearchHarpendenHertfordshire AL5 2JQUnited Kingdom National Maize Research Program Nepal Agricultural Research CouncilChitwan 44209Nepal

Greenhousing is a technique to bridge season gap in vegetable production and has been widely used worldwide. Calculation of water requirement of crops grown in greenhouse and determination of their irrigation schedules in arid and semi-arid regions are essential for greenhouse maintenance and have thus attracted increased attention over the past decades. The most common method used in the literature to estimate crop evapotranspiration（ET） is the Penman-Monteith（PM） formula. When applied to greenhouse, however, it often uses canopy resistance instead of surface resistance. It is understood that the surface resistance in greenhouse is the result of a combined effect of canopy restriction and soil-surface restriction to water vapor flow, and the relative dominance of one restriction over another depends on crop canopy. In this paper, we developed a surface resistance model in a way similar to two parallel resistances in an electrical circuit to account for both restrictions. Also, considering that wind speed in greenhouse is normally rather small, we compared three methods available in the literature to calculate the aerodynamic resistance, which are the r_a^1 method proposed by Perrier（1975a, b）, the r_a^2 method proposed by Thom and Oliver（1977）, and the r_a^3 method proposed by Zhang and Lemeu（1992）. We validated the model against ET of tomatoes in a greenhouse measured from sap flow system combined with micro-lysimeter in 2015 and with weighing lysimeter in 2016. The results showed that the proposed surface resistance model improved the accuracy of the PM model, especially when the leaf area index was low and the greenhouse was being irrigated. We also found that the aerodynamic resistance calculated from the r_a^1 and r_a^3 methods is applicable to the greenhouse although the latter is slightly more accurate than the former. The proposed surface resistance model, together with the r_a^3 method for aerodynamic resistance, offers an improved approach to estimate ET

关键词： canopy resistance surface resistance aerodynamic resistance sap flow system micro-lysimeter weighing lysimeter

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Investigation of the effect of in-situ grown PPy on low frequency dielectric properties and other properties of PVA-PVP blend film

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Journal of Advanced Dielectrics 2021年第4期11卷 7-17页

作者： sushma jha Vaishali Bhavsar k.P.sooraj Mukesh Ranjan Deepti Tripathi Department of Physics School of Science Gujarat UniversityAhmedabadGujaratIndia Applied sciences and Humanities Department sAL College of Engineering AhmedabadGujaratIndia Institute for Plasma Research Gandhinagar GujaratIndia

Present study is carried out to understand the effect of conducting polymer,polypyrrole(PPy)on structural,morphological,thermal and dielectric properties of bio-compatible polymer blend film of polyvinyl alcohol(PVA)and polyvinyl pyrrolidone(PVP).The growth of PPy in the matrix of PVA-PVP was analyzed using XRD,FT-IR and sEM *** shifting in positions and broadening of XRD diffraction peaks of PVA-PVP-PPy from that of PVA-PVP indicates the structural modification and reduction in the crystallinity of the PVA-PVP due to incorporation of *** sEM studies suggest scattered growth of PPy in PVA-PVP matrix at lower concentration of pyrrole *** the monomer concentration is increased,the uniform and interconnected growth of PPy was observed in sEM *** TGA thermograms show faster thermal degradation of PVA-PVP-PPy films at lower temperature as compared to PVA-PVP *** blend films of PVA-PVP-PPy exhibited enhanced values of dielectric constant and ac conductivity as compared to the virgin blend film which are observed to increase with increasing concentration of *** high dielectric constant with high ac conductivity exhibited by PVA-PVP-PPy film suggests its possible application as flexible dielectric material for the development of biosensors,energy storage devices in field of green organic electronics.

关键词： Polyvinyl alcohol polyvinyl pyrrolidone polypyrrole thermal degradation dielectric

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Effects of in ovo delivered xylo-and mannan-oligosaccharides on growth performance,intestinal immunity,cecal short-chain fatty acids,and cecal microbiota of broilers

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Journal of Animal science and Biotechnology 2022年第4期13卷 1099-1114页

作者： Amit kumar singh Utsav Prakash Tiwari Birendra Mishra Rajesh jha Department of Human Nutrition Food and Animal SciencesUniversity of Hawaii at Manoa1955 East-West RdHonoluluHI 96822USA

Background:This study investigated a novel in ovo feeding strategy to determine the prebiotic effects of xylo-and mannan-oligosaccharides(XOs and MOs)differing in the degree of polymerization.A total of 192 fertilized eggs were divided into 6 treatment groups:i)normal saline control(NsC),ii)xylotriose(XOs3),iii)xylotetraose(XOs4),iv)mannotriose(MOs3),v)mannotetraose(MOs4),and vi)no injection control(NIC),each containing 4 replicate trays with 8 eggs per *** d 17 of incubation,3 mg of oligosaccharides(except for controls)dissolved in 0.5 mL of 0.85%normal saline were injected into the amnion of Cobb 500 broilers *** hatch,the chicks were raised for 28 d under standard husbandry practices and were fed a commercial broilers diet ad libitum,and samples were collected ***:The hatchability,growth performance,and relative weights of breast,drumstick,liver,and proventriculus were not different among the treatments(P>0.05).The XOs3 injection increased the total short-chain fatty acid production at d 28 compared with both control groups(Ps height to crypt depth ratio was significantly higher in the XOs4 group than both controls on the hatch day(Ps on d 7 and 28(P>0.05).On the hatch day,the expression level of the CD3 gene(a T cell marker)was increased by XOs3,while the IL-10 gene(a marker of anti-inflammatory cytokine)was reduced by MOs4(Ps,XOs3 exhibited a trend of reduction for IL-10(P=0.074).No cytokines or lymphocyte markers were affected by the treatments on d 7(P>0.05),except XOs4 increased IL-4 compared with NsC(Ps in the MOs4 group had higher operational taxonomic units(OTUs)and had more differentially abundant taxa,including order Lactobacillales and family Leuconostocaceae(Ps on d *** predictive functional profiling indicated that the linoleic acid metabolism pathway w

关键词： Broilers Gut health Immunity in ovo Mannanoligosaccharides Microbiota Oligosaccharides Prebiotics Xylooligosaccharides

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Free-radical scavenging properties of low molecular weight peptide(s) isolated from s1 cultivar of mulberry leaves and their impact on Bombyx mori(L.)(Bombycidae)

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Journal of Animal science and Biotechnology 2014年第3期5卷 348-356页

作者： suchisree jha Palash Mandal Phalguni Bhattacharyya Amitava Ghosh Department of Botany University of North BengalSiliguri 734013West BengalIndia Department of Botany University of North Bengal Department of Botany Malda CollegeUniversity of Gour Banga Department of Botany Asutosh College

The mulberry leaves have been considered as a sole food source for silkworm, Bombyx mori （L.）. In present work an attempt was made to investigate the role of low molecular weight peptide（s） isolated from mulberry leaves on silkworm rearing. Also we have tried to find out the role of free-radical scavenging activities of isolated peptide（s） on silkworm growth. Larval growth rate was found effective under the influence of peptide（s）. Consumption rate of larvae after peptide（s） treatment on mulberry leaves was significantly enhanced over control. High antioxidant activity was found in Low molecular weight peptide（s） which have an effect on silkworm.

关键词： Antioxidant HPLC Low molecular peptide(s) Mulberry leaf silkworm

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Numerical investigation of the effect of transitory strand opening on mixing in a multistrand tundish

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 535-542页

作者： sabin kumar Mishra Pradeep kumar jha satish Chandra sharma satish kumar Ajmani Department of Mechanical and Industrial Engineering Indian Institute of Technology RoorkeeRoorkee 247667UttarakhandIndia steelmaking and Casting Research Group Tata SteelR&DBurma MinesJamshedpur 831007JharkhandIndia

In a multistrand,the outlet near the inlet produces short circuiting *** leads to the formation of dead zones inside the tundish,and consequently,the mean residence time *** the present study,numerical investigation of mixing inside a delta shaped tundish with sloping boundaries was carried out by solving the Navier-stokes equation and employing the standard turbulence *** decrease the dead zone volume inside the tundish,the effect of closing the outlet near the inlet for a small amount of time and further opening it on the mixing behavior of the tundish was *** outlets near the inlet were closed for varying amount of time,and the transient analysis of fluid flow and the tracer dispersion study were carried out to find the mixing parameters of the tundish,namely,mean residence time and the ratio of mixed to dead volume of the *** optimum closure time of the near outlet has been found,which yields best mixing inside the *** numerical code was validated against the experimental observation by performing the tracer dispersion study inside a multistrand tundish and the reasonably good match between the experimental and numerical results in terms of residence time distribution （RTD） *** results obtained from the present study confirm the strong role of choosing the right time for opening and closing the outlets to get improved characteristics for the fluid flow and mixing behavior of the *** educational version of computational fluid dynamics （CFD） software PHOENICs was used to solve the governing equations and interpret the results in different forms.

关键词： continuous casting billets tundish flow simulation mean residence time dead volume computational fluid dynamics (CFD)

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Alternative flat coil design for electromagnetic forming using FEM

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Transactions of Nonferrous Metals society of China 2011年第3期21卷 618-625页

作者： M.AHMED1 s.k.PANTHI N.RAMAkRIsHNAN A.k.jha A.H.YEGNEsWARAN R.DAsGUPTA s.AHMED Advanced Materials and Processes Research Institute(AMPRI) Bhopal -462064 India India science Laboratory GM Bangalore-560066 India Maulana Azad National Institute of Technology ( MANIT) Bhopal-462007 India

Electromagnetic forming （EMF） is a high velocity forming process that uses impulse magnetic force. Coil is an important component of EMF system which needs to be designed depending on application. Flat spiral coils are generally used for electromagnetic forming of sheet metals. However, with this type of coil the central portion of the workpiece experiences marginal magnetic force. This leads to in-sufficient deformation at this portion and other problems like air entrapment. In this study, a conceptual design of flat coil was proposed for better distribution of magnetic forces over the workpiece. Comparative analysis of distribution of magnetic force, magnetic field and current density using the proposed and the existing coil designs were carried out using FEM. The result indicates that the proposed coil design produces comparatively better magnetic force distribution over the workpiece. Calculation of self-inductance of such coils was also carried out and was compared with FE simulation.

关键词： electromagnetic forming flat spiral coil sheet metal forming FEM

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Effect of Al-TiB master alloy addition on microstructure, wear and compressive deformation behaviour of aluminum alloys

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Transactions of Nonferrous Metals society of China 2012年第5期22卷 1001-1011页

作者： D.P.MONDAL Nidhi jha Anshul BADkUL s.DAs Advanced Materials and Processes Research Institute(CsIR LAB) Bhopal 462064India

Aluminum-10% TiB master alloy was added in various proportions in 7178 Al alloy in order to examine the effect of TiB on grain refinement, wear and compressive deformation of the later one. Microstructural characterization reveals that TiB particles act as grain refiners for primary base alloy and result in globular dendrites. It was observed that the wear resistance and strength of the alloy decreased when the master alloy addition increased beyond 20%, even though the dendrites become much finer and almost spherical in nature.

关键词： aluminum alloys grain refinement Al-TiB master alloy compressive deformation sliding wear

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Master curve generation and modeling of ac conductivity for Mn_(0.7+x)Zn_(0.3)si_(x)Fe_(2-2x)O_(4) spinel ferrite system

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Journal of Advanced Dielectrics 2017年第3期7卷 54-63页

作者： N.H.Vasoya Prafulla k.jha k.G.saija J.A.Bhalodia k.B.Modi Department of Physics Faculty of ScienceM.S.University of Baroda Vadodara 390002India smt.R.P.Bhalodia Mahila College Upleta 360490India Department of Physics Saurashtra UniversityRajkot 360005India

The compositional dependence of ac conductivity(δac),real(δ′)and imaginary(δ′′)parts of complex electric conductivity(δ*)was investigated as a function of temperature(T)and frequency(f) for Mn_(0.7+x)Zn_(0.3)si_(x)Fe_(2-2x)O_(4),x=0.0,0.1,0.2 and 0.3 spinel ferrite *** compositional dependence of lattice constant values suggested that the most of the substituted si4+-ions reside at grain boundaries and only a few si-ions are inside *** variation ofδ_(ac)(x,f,T)is explained on the basis of segregation and diffusion of si4+ions at grain boundaries and grains,respectively,and the electrode *** variation of ac conductivity at fixed frequency suggested two different mechanisms which could be responsible for conduction in the *** is found that δ*is not the preferred presentation for dielectric data and the scaling process of real part of conductivity by normalized frequency and the scaled frequency were found *** fitting results of ac conductivity data with path percolation approximation were found suitable in low-frequency regime while in high-frequency regime,effective medium approximation(EMA)was found successful.

关键词： Ferrites ac conductivity scaling modeling.

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Rock fragmentation control in opencast blasting

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Journal of Rock Mechanics and Geotechnical Engineering 2016年第2期8卷 225-237页

作者： P.k.singh M.P.Roy R.k.Paswan Md.sarim suraj kumar Rakesh Ranjan jha CsIR-Central Institute of Mining and Fuel Research

The blasting operation plays a pivotal role in the overall economics of opencast *** blasting subsystem affects all the other associated sub-systems,***,transport,crushing and milling *** control through effective blast design and its effect on productivity are the challenging tasks for practicing blasting engineer due to inadequate knowledge of actual explosive energy released in the borehole,varying initiation practice in blast design and its effect on explosive energy release *** paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in *** mines use draglines and shoveledumper combination for removal of *** its pivotal role in controlling the overall economics of a mining operation,the expected blasting performance is often judged almost exclusively on the basis of poorly defined parameters such as powder factor and is often qualitative which results in very subjective assessment of blasting *** an approach is very poor substitutes for accurate assessment of explosive and blasting *** one blasts were conducted with varying blast designs and charging patterns,and their impacts on the rock fragmentation were documented.A high-speed camera was deployed to record the detonation sequences of the *** efficiency of the loading machines was also correlated with the mean fragment size obtained from the fragmentation analyses.

关键词： Opencast blast Rock fragmentation Explosives performance Dragline efficiency Fragment size

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Effect of impinging angle and rotating speed on erosion behavior of aluminum

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Transactions of Nonferrous Metals society of China 2011年第1期21卷 32-38页

作者： A.k.jha R.BATHAM M.AHMED A.k.MAJUM DER O.P.MODI s.CHATURVEDI A.k.GUPTA Advanced Materials and Processes Res earch Institute

Commercial aluminum（grade 1900） in rotary motion was exposed to slurry of sand in *** were mounted at various angles and rotated at different *** rate was calculated using mass loss *** results show that wear rates increase with increasing impingement angle up to 90°.Contrary to the conventional understanding of maximum loss of ductile material at about 45° impingement angle,maximum wear rate was observed in case of the aluminum sample fixed at 90°.However,increasing rotation speed of the samples results in exponential increase in wear *** findings are substantiated with the metallographic study of worn surface.

关键词： aluminum slurry erosion impinging wear

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