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Water and nitrogen input optimization for jujube trees under surge root irrigation based on weighted grey correlation model

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International Journal of Agricultural and Biological Engineering 2019年第3期12卷 45-51页

作者： Zhiguang Dai Liangjun Fei yun zhong Deliang Huang Institute of Water Resources Research Xi’an University of TechnologyXi’an 710048China School of Hydraulic and Ecological Engineering Nanchang Institute of TechnologyNanchang 30099China

In order to obtain the optimal input of water and nitrogen(W&N)suitable for the jujube trees in Northern Shaanxi,12 treatments had been set in the demonstration base of micro-irrigation jujube tree of Mizhi County in 2014-2015 through field experiment of jujube trees under surge root irrigation(SRI),in which three soil moisture levels(high moisture level W1:60%-85%θ,middle moisture level W2:50%-75%θ,low moisture level W3:40%-65%θ)and four nitrogen input levels(high nitrogen F75:0.75 kg/plant,middle nitrogen F50:0.50 kg/plant,low nitrogen F25:0.25 kg/plant,no nitrogen F0:0.00 kg/plant)were *** analyzing the effects of different W&N inputs on the yield,net income(NI)and W&N utilization efficiency(WUE and NUE)of jujube trees and establishing a weighted grey correlation model,the optimization of W&N input for jujube trees could be achieved under *** showed that different W&N inputs had significant influences on yield,NI,WUE and *** with the increase of soil moisture content,the yield and NUE increased,while WUE decreased gradually,and the NI had the tendency to increase first and then *** with the increase of nitrogen input,the yield,NI and WUE had the tendency to increase first and then decrease while the NUE decreased significantly,and the yield,NI,WUE and NUE could not reach the maximum at the same *** the study on the grey correlation model of jujube tree’s comprehensive benefit based on the yield,NI,WUE and NUE,results showed the comprehensive benefit of jujube trees was significantly different when W&N input was different,and the gray correlation degree of W2F25 treatment was the highest in two years,which means that the soil moisture content of 50%-75%θand nitrogen input of 0.25 kg/plant was the optimal W&N input for jujube trees under SRI in Northern Shaanxi area.

关键词： surge root irrigation input of water and nitrogen jujube tree comprehensive benefit grey correlation model

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Multiple immune function impairments in diabetic patients and their effects on COVID-19

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World Journal of Clinical Cases 2021年第24期9卷 6969-6978页

作者： zhong-Hua Lu Wei-Li Yu yun Sun Department of Critical Care Medicine The Second Affiliated HospitalAnhui Medical UniversityHefei 230601Anhui ProvinceChina

Coronavirus disease 2019(COVID-19),which is caused by severe acute respiratory syndrome coronavirus 2,poses a significant threat to public health worldwide,and diabetes is considered a risk factor for the rapid progression and poor prognosis of *** immune function is a clinical feature of COVID-19 patients,and diabetes patients have defects in innate and adaptive immune functions,which may be an important reason for the rapid progression and poor prognosis of COVID-19 in patients with *** review the possible multiple effects of immune impairment in diabetic patients on the immune responses to COVID-19 to provide guidance for the diagnosis and treatment of diabetic patients with COVID-19.

关键词： COVID-19 Diabetes Immune function SARS-CoV-2

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Teleporation of an Arbitrary Two-Particle State Without Bell-State Measurement in Cavity QED

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Communications in Theoretical Physics 2008年第6期49卷 1596-1598页

作者： zhong Zhi-Rong YE Sai-yun SU Wan-Jun Department of Electronic Science and Applied Physics Fuzhou University Fuzhou 350002 China

A scheme for approximately conditional teleportation of an arbitrary two-particle state without Bell-state measurement in cavity QED is presented. The scheme involves four two-level atoms and two single-mode cavities. The detection of atoms 3 and 4 collapses the atoms 1 and 2 to the initial state of atoms 3 and 4, while the cavity fields left in the vacuum state. The probability of success and the fidelity of our scheme are 0.125 and 0.98, respectively.

关键词： teleportation arbitrary two-particle state

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Study on smoke propagation in tunnel construction of a hydropower station: A full-scale fire experiment

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Journal of Safety Science and Resilience 2023年第2期4卷 188-202页

作者： Chang Liu Huihang Cheng Wenjun nie Senlin Jiang Junfeng Chen Peng Lin Maohua zhong Institute of Public Safety Research Departnent of Engineering PhysicsTsinghua UniverstyBeijing 100084China China Electric Power Research Institute Beijing 100192China Sinohydro Bureau 6 Co. LTDShenyang 110179China Department of Hydraulic Engineering Tsinghua UniversityBeijing 100084China

In this study,full-scale fire experiments were conducted in a hydropower station to investigate smoke propagation during tunnel *** flame height,smoke temperature and stratification,smoke descent and spread velocity were analyzed via measurements and on-site *** initial combustion stage was largely affected by ignition source during tunnel construction for diesel pool fire,and the average flame height in the fully developed stage could reach 1.4-2.1 m in experimental fire *** gradient of the smoke temperature evolution near the fire was the opposite for the upstream and downstream *** longitudinal temperature distribution was concentrated in a small range at the heights of the smoke layer,and gradually decreased by air entrainment as the height decreased,while further increasing in the lower half of the tunnel height in the near-fire region under heat radiation from the fire ***,distinct and stable smoke stratification formed during the fully developed combustion stage,and the smoke layer interface was at approximately half the tunnel *** descent was aggravated in the decay stage of combustion,and the fire risk remained high after the fully developed *** smoke front spread velocity was empirically determined for the full-scale tunnel fire *** from full-scale experiments can support smoke control design and on-site fire emergency response plans for hydropower stations.

关键词： Full-scale experiment Fire Smoke propagation Construction tunnel Hydropowerstation

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(Z)-a-Selanyl Alkenyl Grignard Reagents as Convenient Precursors for Stereoselective Synthesis of Trisubstituted Alkenes

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Chinese Chemical Letters 2002年第12期13卷 1164-1167页

作者： Ming zhong CAI Chun yun PENG Jia Di HUANG Department of Chemistry Jiangxi Normal UniversityNanchang 330027

Z)-a-Selanyl alkenyl Grignard reagents 2 were prepared conveniently by treatment of a-bromovinylselenides 1 with magnesium filings in THF. Intermediates 2 were reacted with alkyl iodides in the presence of CuI or Pd(PPh3)4 to afford (Z)-1,2-disubstituted vinylselenides 3, which were cross-coupled with Grignard reagents in the presence of (PPh3)2NiCl2 to give trisubstituted alkenes 4 stereoselectively in good yields.

关键词： a-Bromovinylselenides (Z)-a-selanyl alkenyl Grignard reagents stereoselective synthesis trisubstituted alkene.

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Effects of the sand content of muddy water content on one-dimensional vertical infiltration characteristics and dense layer formation characteristics

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 172-179页

作者： Shouxuan Kang Liangjun Fei yun zhong Lihua Liu State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an 710048China Institute of Water Resources and Hydro-electric Engineering Xi’an University of TechnologyXi’an 710048China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002HubeiChina School of Water Conservancy and Hydroelectric Power Hebei University of EngineeringHandan 056038HebeiChina

Muddy water irrigation,an effective water-saving irrigation method,has been widely used in the Yellow River Basin in *** investigate the effect of sand content on water infiltration and dense layer formation under one-dimensional vertical infiltration of muddy water,muddy water infiltration experiments were performed in the laboratory,and five sand contents of muddy water(S=0%,3%,6%,9%,and 12%)were *** were established to describe the relationship between the cumulative infiltration amount[I(t)]and the infiltration duration(t);the relationship among the migration distance of the wetting front(Z),S,and t;the thickness of the sedimentary layer[H(t)];and the relationship between S and *** results revealed that I(t)and Z decreased significantly with the increase of sand contents,while H(t)increased significantly with the increase of sand contents.I(t)and Z were in the range of 7 cm and 20 cm for each treatment,*** variation in I(t)with t fitted Kostiakov and Philip models,and the coefficients of determination were all greater than *** the increase in S,the infiltration coefficient gradually decreased,the infiltration index gradually increased,and the sorptivity gradually *** particle composition of the sedimentary layer was similar to that of the argillaceous sediment,and the content of particles with a size of less than 2 mm in the sedimentary layer was lower than that of the argillaceous *** with the original soil,the content of particles with a size of less than 0.05 mm and physical clay particles(diameter less than 0.01 mm)in the soil with an infiltration depth of 0-2 cm *** retention layer was from the topsoil to the infiltration depth of approximately 2 *** study can provide a scientific basis for further research on soil infiltration mechanisms under muddy water.

关键词： muddy water sand content dense layer cumulative infiltration wetting front transport deposit layer thickness

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Effect of Magnetic Field on Synthesis of Nano-FeOOH by Low-Temperature Neutralization Method

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Journal of Iron and Steel Research International 2012年第S2期19卷 1089-1094页

作者： zhong yun-bo SUN Zong-qian TANG nie-wei XU Bin FU Xiao-ming WANG Jiang Shanghai Key Laboratory of Modern Metallurgy and Material Processing Shanghai University

Using XRD,TEM and VSM methods,the phase,morphology and magnetic property of iron hydroxide oxide(FeOOH) which has been prepared by low-temperature neutralization reaction under different magnetic fields were *** can be found that the magnetic field had a great influence on the *** goethite(α-FeOOH) was synthetized without magnetic *** the magnetic flux density was increased to 0.1T,γ-FeOOH was *** the magnetic field intensity was raised to 0.5T,the product was all composed of δ-***,the crystallization of FeOOH was greatly influenced by magnetic field as *** calculation results show that the magnetic free energy of chemical reaction reached to more than hundreds KJ/mol when the magnetic field is *** meaned that the application of magnetic field was conducived to producing the products with higher *** under the low magnetic field,due to the stability of the reaction products was broken by the magnetic field,the magnetic free energy was also effective.

关键词： Magnetic field FeOOH Magnetic free energy Low-temperature neutralization method chemical reaction

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Microstructure and Thermal Conductivity of As-Cast and As-Solutionized Mg–Rare Earth Binary Alloys

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Journal of Materials Science & Technology 2017年第11期33卷 1240-1248页

作者： Liping zhong Jian Peng Song Sun Yongjian Wang yun Lu Fusheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and Engineering Chongqing University Chongqing 400044 China Chongqing Academy of Science and Technology Chongqing 401127 China Graduate School & Faculty of Engineering Chiba University Chiba 263-8522 Japan

The microstructure and thermal conductivity of four groups of Mg–rare earth（RE） binary alloys（Mg–Ce,Mg–Nd, Mg–Y and Mg–Gd） in as-cast and as-solutionized states were systematically studied. Thermal conductivity was measured on a Netzsch LFA457 using laser flash method at room temperature. Results indicated that for as-cast alloys, the volume fraction of second phases increased with the increase of alloying elements. After solutionizing treatment, a part or most of second phases were dissolved in α-Mg matrix, except for Mg–Ce alloys. The thermal conductivity of as-cast and as-solutionized Mg–RE alloys decreased with the increase of concentrations. The thermal conductivity of as-solutionized Mg–Nd,Mg–Y and Mg–Gd alloys was lower than that of as-cast alloys. Thermal conductivity of as-solutionized Mg–Ce alloys was higher than that of as-cast alloys, because of the elimination of lattice defects and fine dispersed particles during solutionizing treatment. Different RE elements have different influences on the thermal conductivity of Mg alloys in the following order： Ce 〈 Nd 〈 Y 〈 Gd. Ce has the minimum effect on thermal conductivity of Mg alloys, because of the very low solubility of Ce in the α-Mg matrix. The variations in the atomic radius of the solute elements with Mg atom（ r）, valence, configuration of extranuclear electron of the solute atoms, and the maximum solid solubility of elements in the α-Mg matrix were suggested to be the main reasons for the differences in thermal conductivity of resulting Mg–RE alloys.

关键词： Mg alloys Rare earth elements Microstructure Thermal conductivity

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A Silole-Based Efficient Electroluminescent Material with Good Electron-Transporting Potential

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Chinese Journal of Chemistry 2015年第8期33卷 842-846页

作者： Changyun QuanI Han nie Rongrong Hu Anjun Qin Zujin Zhao Ben zhong Tang Guangdong Innovative Research Team State Key Laboratory of Luminescent Materials andDevices South China University of Technology Gt4angzhou 510640 China Department of Chemistry The Hong Kong University of Seience & Technology Clear Water Bay Kowloon Hong Kong China

A new silole derivative, 2,5-bis（7-（dimesitylboranyl）-9,9-dimethylfluoren-2-yl）- 1 -methyl- 1,3,4-triphenylsilole （（MesBF）2MTPS）, is synthesized and characterized. （MesBF）2MTPS shows a good fluorescence efficiency of 15% in THF solution and a higher efficiency of 86% in solid film, presenting an aggregation-enhanced emission charac- teristic. It is thermally and morphologically stable, with high decomposition and glass-transition temperatures of 257 and 171 ℃, respectively. The LUMO energy level （-2.96 eV） of （MesBF）zMTPS is lower than that of TPBi, revealing its electron-transporting potential. Efficient organic light-emitting diodes （OLEDs） are fabricated using （MesBF）2MTPS as emitter, which radiates yellow light at 554 nm, and affords high maximum luminance, current efficiency, and external quantum efficiency of 48348 cd·m^-2, 12.3 cd·A^-1, and 4.1%, respectively.

关键词： silole aggregation-enhanced emission electroluminescence electron transporter organic light-emitting diodes

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'Ship-in-a-Bottle' Approach to Synthesize Ag@hm-SiO2 Yolk/Shell Nanospheres

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Chinese Journal of Chemical Physics 2015年第5期28卷 -页

作者： Wei-qiang Li Guo-zhong Wang Guang-hai Li yun-xia Zhang Key Laboratory of Materials Physics Centre for Environmental and Energy Nanomaterials and Anhui Key Laboratory of Nanomaterials and Nanotechnology Institute of Solid State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 230031 China Key Laboratory of Materials Physics Centre for Environmental and Energy Nanomaterials and Anhui Key Laboratory of Nanomaterials and Nanotechnology Institute of Solid State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 230031 ChinaSchool of Chemistry and Materials Science University of Science and Technology of China Hefei 230026 China

An effective protocol is presented for the synthesis of Ag@hm-SiO2 yolk/shell nanostructures (YSNs) via a facile “ship-in-a-bottle” method. TEM observations show that the as-obtained Ag@hm-SiO2 YSNs have a single silver core in the interior of hollow mesoporous silica (hm-SiO2) nanospheres, in which the thickness of hm-SiO2 outer shell is about 14 nm and the silver core has an average size of about 43 nm. And the content of silver in Ag@hm-SiO2 YSNs is about 10.29% based on the inductively coupled plasmameasurement. The as-synthesized Ag@hm-SiO2 YSNs exhibited significantly enhanced catalytic performance compared with the pure Agnanoparticles toward the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4.

关键词： Ag@hm-SiO2 Yolk/shell Ship-in-a-bottle Nanoreactor

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