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Chinese Journal of Structural Chemistry 2007年第5期26卷 599-605页

作者： LIU Ying DOU Jian-min WANG Da-Qi zhang xian-Xi LI Da-Cheng XU Feng ZHOU Lei College of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 China

One new polyoxometalate compound connected via nickel/potassium cations, H8K{[Ni（H2O）5]2（H2Mo1.80W10.20O42）}Cl3·16H2O 1, was prepared and characterized by elemental analysis and IR spectroscopy. Single-crystal X-ray diffraction analysis results reveal that clusters of [Ni（H2O）5]2（H2Mo1.80W10.20O42）}^6-in compound 1 are linked by potassium cations to form one- dimiensional chains, based on which a three-dimensional network is further constructed via the hydrogen bonds of O…O and O…Cl. Magnetic measurements show that compound 1 has paramagnetic properties. Crystal data： H62Cl3KMo1.80Ni2O68W10.20, Mr = 3461.33, monoclinic, space group C2/c, a = 18.9291（19）, b = 16.6758（17）, c = 19.1064（19）A, β = 106.6880（10）°, V = 5777.1（10）A^3, Z = 4, Dc = 3.980 g/cm^3, F（000） = 6250, μ = 21.574 mm^-1, R = 0.0579 and wR = 0.1623 （Ⅰ 〉 2σ（Ⅰ））.

关键词： polyoxomolybdate molybdate nickel sodium X-ray analysis magnetic

Ultimate Lateral Capacity of Rigid Pile in c–φ Soil

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China Ocean Engineering 2018年第1期32卷 41-50页

作者： zhang Wei-min Nanjing Hydraulic Research Institute Nanjing 210029China Key Laboratory of Water Scienceand Engineering Ministry of Water ResourcesNanjing 210029China National Energy Hydropower Engineering Safetyand Environmental Research and Development Center Nanjing 210029China

To date no analytical solution of the pile ultimate lateral capacity for the general c–φ soil has been obtained. In the present study, a new dimensionless embedded ratio was proposed and the analytical solutions of ultimate lateral capacity and rotation center of rigid pile in c–φ soils were obtained. The results showed that both the dimensionless ultimate lateral capacity and dimensionless rotation center were the univariate functions of the embedded ratio. Also,the ultimate lateral capacity in the c–φ soil was the combination of the ultimate lateral capacity（f;） in the clay, and the ultimate lateral capacity（f;） in the sand. Therefore, the Broms chart for clay, solution for clay（φ=0） put forward by Poulos and Davis, solution for sand（c=0） obtained by Petrasovits and Awad, and Kondner’s ultimate bending moment were all proven to be the special cases of the general solution in the present study. A comparison of the field and laboratory tests in 93 cases showed that the average ratios of the theoretical values to the experimental value ranged from 0.85 to 1.15. Also, the theoretical values displayed a good agreement with the test values.

关键词： pile ultimate lateral capacity dimensionless analytical solution c–φ soils hyperbolic function method

Ultralight and superelastic MXene/reduced graphene oxide aerogels for electromagnetic interference shielding

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Nano Research 2025年第1期18卷 1-9页

作者： Xinfeng Zhou Yang Dai Guoyao Yue Yiman zhang Lulu Li Zhong-Zhen Yu Peng min Hao-Bin zhang 21 State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Advanced Functional Polymer Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Present address:BOE Technology Innovation Center BOE Technology Group Co.Ltd.Beijing 100176China Xi’an Modern Chemistry Research Institute Xi’an 710065China

Lightweight aerogels feature multifunctionality and a high porosity,yet accompanied with poor structure recovery under large strain *** this work,we develop an air bubble-ice crystal dual template and annealing strategy to integrate low density and high resilience for the conductive transition metal carbides/nitrides(MXene)composite *** air bubbles and ice crystals synergistically exclude the nanosheets to the gas-liquid interfaces,thereby constructing unique Y-shaped junctions and robust *** annealing process greatly enhances the interlayer *** external load,the Yshaped structures prevent the stress concentration at the junctions by transferring the forces to the skeleton for maintaining structural *** addition,the wrinkled and thick cell walls,together with the enhanced interlayer interactions,endow the aerogel with exceptional structural stability and *** a result,the MXene/reduced graphene oxide(RGO)composite aerogels exhibit superelasticity with reversible compressive strains of up to 95%.In addition,the electron bridging effect of the RGO sheets affords the aerogel to deliver excellent electromagnetic interference shielding performance,as high as 46.3 dB at 2.5 ***,the remarkable reshapeability of the aerogels allows for precise regulation of structure and performance(33.5-75.1 dB)by a simple wetting compression *** summary,this work offers helpful inspirations for developing lightweight and superelasticity aerogels for extensive applications.

关键词： lightweight superelasticity MXene aerogel electromagnetic interference shielding reshapeability

Fracture gradient prediction:an overview and an improved method

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Petroleum Science 2017年第4期14卷 720-730页

作者： Jincai zhang Shang-xian Yin Geomech Energy HoustonTXUSA North China Institute of Science and Technology YanjiaoBeijing 101601China Present Address:Sinopec Tech HoustonTXUSA

The fracture gradient is a critical parameter for drilling mud weight design in the energy industry. A new method in fracture gradient prediction is proposed based on analyzing worldwide leak-off test(LOT) data in offshore drilling. Current fracture gradient prediction methods are also reviewed and compared to the proposed method. We analyze more than 200 LOT data in several offshore petroleum basins and find that the fracture gradient depends not only on the overburden stress and pore pressure, but also on the depth. The data indicate that the effective stress coefficient is higher at a shallower depth than that at a deeper depth in the shale formations. Based on this finding,a depth-dependent effective stress coefficient is proposed and applied for fracture gradient prediction. In some petroleum basins, many wells need to be drilled through long sections of salt formations to reach hydrocarbon *** fracture gradient in salt formations is very different from that in other sedimentary rocks. Leak-off test data in the salt formations are investigated, and a fracture gradient prediction method is proposed. Case applications are examined to compare different fracture gradient methods and validate the proposed methods. The reasons why the LOT value is higher than its overburden gradient are also explained.

关键词： Fracture gradient prediction Leak-off test Breakdown pressure Mud loss Fracture gradient in salt

Warming effects on plant biomass allocation and correlations with the soil environment in an alpine meadow,China

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Journal of Arid Land 2016年第5期8卷 773-786页

作者： XU Manhou LIU min XUE xian ZHAI Datong Taiyuan Normal University Jinzhong 030619 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Alpine meadow ecosystem is fragile and highly sensitive to climate *** understanding of the allocation of above-and below-ground plant biomass and correlations with environmental factors in alpine meadow ecosystem can result in better protection and effective utilization of alpine meadow *** chose an alpine meadow in the Qinghai-Tibetan Plateau of China as the study area and designed experimental warming plots using a randomized block experimental *** used single-tube infrared radiators as warming devices,established the warming treatments,and measured plant above- （AGB） and below-ground biomass （BGB） during the growing seasons （May to September） in 2012 and *** determined the allocation of biomass and the relationship between biomass and soil environment under the warming *** indices including above-ground biomass,below-ground biomass and the ratio of root to shoot （R/S） ,and soil factors including soil moisture and soil temperature at different depths were *** results showed that （1） BGB of the alpine meadow had the most significant allometric correlation with its AGB （y=298.7x~ （0.44） ,P〈0.001） ,but the relationship decreased under warming treatment and the determination coefficient of the functional equation was 0.102 which was less than that of 0.188 of the unwarming treatment （control） ; （2） BGB increased,especially in the deeper soil layers under warming treatment （P〉0.05） .At 0–10 cm soil depth,the percentages of BGB under warming treatment were smaller than those of the control treatment with the decreases being 8.52% and 8.23% in 2012 and 2013,***,the BGB increased 2.13% and 2.06% in 2012 and 2013,respectively,at 10–50 cm soil depths; （3） BGB had significant positive correlations with soil moisture at 100 cm depth and with soil temperature at 20–100 cm depths （P〈0.05） ,but the mean correlation coefficient of soil temperature was 0.354,greater than the 0.245 of soil moisture.R/S ratio had a s

关键词： alpine meadow above-ground biomass below-ground biomass soil environment warming

Altered hACE2 binding affinity and S1/S2 cleavage efficiency of SARS-CoV-2 spike protein mutants affect viral cell entry

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Virologica Sinica 2023年第4期38卷 595-605页

作者： Ke Wang Yu Pan Dianbing Wang Ye Yuan min Li Yuanyuan Chen Lijun Bi xian-En zhang National Key Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing100101China Faculty of Synthetic Biology Shenzhen Institute of Advanced TechnologyShenzhen518055China University of Chinese Academy of Sciences Beijing100101China

SARS-CoV-2 variants are constantly emerging,hampering public health measures in controlling the number of *** it is well established that mutations in spike proteins observed for the different variants directly affect virus entry into host cells,there remains a need for further expansion of systematic and multifaceted ***,we comprehensively studied the effect of spike protein mutations on spike expression and proteolytic activation,binding affinity,viral entry efficiency and host cell tropism of eight variants of concern(VOC)and variants of interest(VOI).We found that both the full-length spike and its receptor-binding domain(RBD)of Omicron bind to hACE2 with an affinity similar to that of the *** addition,Alpha,Beta,Delta and Lambda pseudoviruses gained significantly enhanced cell entry ability compared to the wild-type,while the Omicron pseudoviruses showed a slightly increased cell entry,suggesting the vastly increased rate of transmission observed for Omicron variant is not associated with its affinity to *** also found that the spikes of Omicron and Mu showed lower S1/S2 cleavage efficiency and inefficiently utilized TMPRSS2 to enter host cells than others,suggesting that they prefer the endocytosis pathway to enter host ***,all variants'pseudoviruses we tested gained the ability to enter the animal ACE2-expressing *** the infection potential of rats and mice showed significantly increased,strongly suggesting that rodents possibly become a reservoir for viral *** insights gained from this study provide valuable guidance for a targeted approach to epidemic control,and contribute to a better understanding of SARS-CoV-2 evolution.

关键词： SARS-CoV-2 Variants of Concern(VOC) Omicron Binding affinity Viral entry Host-tropism

Approach of Synthesizing Model Predictive Control and Its Applications for Rotary Kiln Calcination Process

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Journal of Iron and Steel Research International 2013年第8期20卷 14-19页

作者： zhang Li GAO xian-wen School of Mechanical Electrical and Information EngineeringShandong University School of Information Science and Engineering Northeastern University

An actual control demand of rotary kiln is taken as background. By analyzing and improving approach of MPC （synthesizing model predictive control）, an effective strategy which applies complex S-MPC in actual industrial process is designed. Firstly, after analyzing the main components technology and calcination reaction mechanism in detail, the calcining belt state-space model of rotary kiln is built using PO-Moesp （past-output multivariable output error state space model identification） method. Then, calcining belt temperature predictive control system is de signed. The control system combines time-delay gain scheduled, output-tracking, recursive subspace adaptive and other methods, and forms the off-line/on-line predictive controller of rotary kiln. At last, MATLAB is applied for simulation, experiments run in constant value tracking and servo tracking situation. Simulation results show its ef- fectiveness and feasibility.

关键词： synthesizing model predictive control~ scheduled tracking linear matrix inequality~ rotary kiln soft sensor

Watermark Embedding for Direct Binary Searched Halftone Images by Adopting Visual Cryptography

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Computers, Materials & Continua 2018年第5期55卷 255-265页

作者： Yangyang Wang Rongrong Ni Yao Zhao min xian Beijing Key Laboratory of Advanced Information Science and Network Technology Institute of Information ScienceBeijing Jiaotong UniversityBeijing 100044China Department of Computer Science University of IdahoIdaho FallsID 83402United States

In this paper,two methods are proposed to embed visual watermark into direct binary search(DBS)halftone images,which are called Adjusted Direct Binary Search(ADBS)and Dual Adjusted Direct Binary Search(DADBS).DADBS is an improved version of *** using the proposed methods,the visual watermark will be embedded into two halftone images separately,thus,the watermark can be revealed when these two halftone images are *** results show that both methods can achieve excellent image visual quality and decoded visual patterns.

关键词： Data hiding halftone direct binary search visual watermark.

The coupled effect of light and temperature on dormancy release and germination of Pinus koraiensis seeds

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Journal of Forestry Research 2022年第4期33卷 1135-1144页

作者： min zhang Jiaojun Zhu Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016People’s Republic of China Qingyuan Forest CERN Chinese Academy of SciencesShenyang 110016People’s Republic of China

Elucidating the regulatory mechanisms of environmental factors on seed dormancy and germination will provide guidance for tree *** understanding the coupled effect of light and temperature on dormancy release and germination of Pinus koraiensis seeds,we set up three light conditions(L200:200μmol m^(-2) s^(-1),L20:20μmol m^(-2) s^(-1),L0:0μm^(-2) s^(-1))and four storage temperatures[T-5:-5°C(50 days),T5:-5°C(50 days)+5°C(50 days),T25:-5°C(50 days)+5°C(50 days)+25°C(50 days),T15:-5°C(50 days)+5°C(50 days)+25°C(50 days)+15°C(50 days)]using imbibed seeds,then quantified phytohormones gibberellic acid(GA_(3))and abscisic acid(ABA)during the *** percentage(G_(P)),mean germination time(T_(M)),and germination value(G_(V))under 25/15°C temperature and the three light conditions were then *** levels and germination performances were significantly affected by light and *** consistent trend was found between the phytohormone levels and G_(P) caused by light *** the three light conditions,ABA concentrations in the embryo and endosperm decreased as storage temperature shifted from T-5 to T25 and increased from T25 to T15;GA_(3) decreased in nearly all four storage temperatures.G_(P) reached 40–60%in T25 storage without light *** the three light conditions,G_(P) and G_(V) were higher at T5 and T25 than at T-5 and T15;so T5 and T25 are considered as optimum storage temperatures for dormancy release and *** optimum temperatures,light(L200,L20)significantly increased the G_(P) and G_(V) compared with the dark(L0).At L200 and L20,significant negative correlations between G_(V) and the ABA concentrations and positive correlations between G_(V) and GA/ABA in the seed embryo were *** played a more important role in primary dormancy release and germination;light was unnecessary for primary dormancy *** facilitated seed germination at optimum *** dormancy

关键词： Seed germination Gibberellic acid Abscisic acid Germination percentage Cold stratification Primary dormancy

C~∞-solutions for the Second Type of Generalized Feigenbaum's Functional Equations

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Acta Mathematica Sinica,English Series 2014年第10期30卷 1785-1794页

作者： min zhang College of Science China University of Petroleum

This work focuses on the second type of generalized Feigenbaum＇s equation {φ（f（x））=f（f（φ（x）））,f（0）=1,0≤f（x）≤1,x∈{0,1},where φ（x） is C∞-increasing function on [0, 1] and satisfies that φ（0） = 0,0 〈 φ′（x）〈 1 （x ∈ [0, 1]）. Using constructive method, we discuss the existence of C∞-single-valley solutions whose derivatives are not equal to 0 on origin of the above equation.

关键词： F^nctional equation constructive method initial function C∞-single-valley solution