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Contribution of soil fauna to the degradation of recalcitrant components in Cinnamomum camphora foliar litter in different-sized gaps in Pinus massoniana plantations

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Journal of Forestry Research 2019年第3期30卷 931-941页

作者： Yan zhang Danju zhang Xun Li jian zhang Institute of Ecology and Forestry College of Forestry Chengdu 611130People’s Republic of China Collaborative Innovation Center of Ecological Security in the Upper Reaches of Yangtze River Chengdu 611130People’s Republic of China

Forest gaps are important in forest dynamics and management, but little is known about how soil fauna influence the degradation of recalcitrant litter components in different-sized forest gaps. This investigation uses litterbags with two different mesh sizes (0.04 and 3 mm) to control the meso- and microfauna entering the bags to quantify the contribution of soil fauna to the degradation of recalcitrant components (including condensed tannins, total phenol, lignin and cellulose) during litter decomposition. The experiment was conducted in seven different forest gap sizes in Pinus massoniana plantations over 1 year. One closed-canopy site (CC) and forest gap sizes of 100, 225, 400, 625, 900, 1225 and 1600 m^2 were created in a P. massoniana plantation in the Sichuan basin of China;the CC was treated as the control. Cinnamomum camphora foliage from local native trees was used in all forest gap experiments. We found the following:(1) Gap size had significant effects on the degradation rates (E) of condensed tannins and lignin and on the contributions of soil fauna;medium-sized gaps also presented high degradation rates. Soil fauna obviously contributed to the degradation of recalcitrant foliar litter components in medium-sized gaps.(2) The highest contribution to degradation (40.98%) was recorded for lignin, and the lowest contribution (0.29%) was recorded for condensed tannins. The results indicate that medium-sized gaps (900 m^2) were conducive to the degradation of recalcitrant litter components by soil fauna.

关键词： Cinnamomum camphora Foliar litter Gap size Pinus massoniana Recalcitrant litter components Soil fauna

Processing technologies for gold-telluride ores

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 1-10页

作者： jian zhang Yao zhang William Richmond Hai-peng Wang Department of Metallurgical Engineering and Extractive Metallurgy Curtin University of Technology WASM Kalgoorlie WA 6430 Australia Department of Applied Chemistry Curtin University of Technology Bentley WA 6102 Australia

Gold telluride ores are important gold refractory ores due to the presence of sulfides and other gangue materials. The classification and main physical properties of gold telluride ores were described, and possible treatment methods including flotation, leaching, and oxidation were reviewed. The results show that flotation procedures are much easier for gold tellurides compared to other refractory gold-bearing ores. For the conventional cyanide leaching process, pretreatment such as oxidation is required to achieve high gold recovery. Roasting is a relatively simple but not environment-friendly method; bio-oxidation technology seems to be more suitable for the oxidation of flotation concentrate. Other treatment methods involve cyanide leaching, thiourea leaching, ammoniacal thiosulfate leaching, carbon-in-pulp, and resin-in-pulp, all of which are less commonly utilized.

关键词： gold-tellurides flotation leaching oxidation

Robust exponential stability analysis of a larger class of discrete-time recurrent neural networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1912-1920页

作者： zhang jian-hai zhang Sen-lin LIU Mei-qin Department of System Science ＆ Engineering School of Electrical Engineering Zhejiang University Hangzhou 310027 China

The robust exponential stability of a larger class of discrete-time recurrent neural networks (RNNs) is explored in this paper. A novel neural network model, named standard neural network model (SNNM), is introduced to provide a general framework for stability analysis of RNNs. Most of the existing RNNs can be transformed into SNNMs to be analyzed in a unified way. Applying Lyapunov stability theory method and S-Procedure technique, two useful criteria of robust exponential stability for the discrete-time SNNMs are derived. The conditions presented are formulated as linear matrix inequalities (LMIs) to be easily solved using existing efficient convex optimization techniques. An example is presented to demonstrate the transformation procedure and the effectiveness of the results.

关键词： Standard neural network model (SNNM) Robust exponential stability Recurrent neural networks (RNNs) Discrete-time Time-delay system Linear matrix inequality (LMI)

Preparation and Molecular Structure of (SCZ)(TNPG)·2H_2O

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Chinese Journal of Structural Chemistry 2005年第8期24卷 973-979页

作者： CHEN Hong-Yan zhang Tong-Lai zhang jian-Guo State Key Laboratory of Prevention and Control of Explosion Disasters and School of Science Beijing Institute of Technology Beijing 100081 China

The （SCZ）（TNPG）.2H2O prepared by mixing semicarbazide （SCZ） and trinitrophloroglucinol （TNPG） was characterized by elemental analysis and IR measurement, and its crystal structure was determined by X-ray single-crystal diffraction analysis. The crystal belongs to triclinic,space group P1, （NH2CONHNH3）^＋（C6H2N3O9）^-·2H2O, Mr = 372.23, a = 0.68853（14）, b =0.93966（19）, c = 1.1925（2） nm, α = 67.48（3）, β = 77.56（3）, γ = 78.93（3）°, V = 0.6908（2） nm^3, Z = 2,Dc = 1.789 g/cm^3, Mr = 373.23, F（000） = 384, S = 0.999 and μ（MoKa） = 0.172 mm^-1. The final R and wR are 0.0394 and 0.1057 for 1724 observed reflections with I 〉 2σ（I）. It is concluded that （SCZ）（TNPG） 2H2O is an ionic compound composed of a cation SCZ^＋, an anion TNPG- and two water molecules. The TNPG anion and SCZ^＋ cation are bonded together by electrostatic attraction and hydrogen bonds, and the compound structure is stable. The thermal decomposition of （SCZ）（TNPG） 2H2O was studied by using TG-DTG and DSC techniques with a heating rate of 10 ℃/min, showing the compound contains one endothermic process of dehydrating stage and two intensive exothermic decomposition stages. The enthalpy of exothermic decomposition reaction is 452.31 kJ/mol.

关键词： semicarbazide trinitrophloroglucinol preparation crystal structure

MAF-41 with intermediate-sized molecular sieving effect for highly selective separation of styrene

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Science China Chemistry 2019年第10期62卷 1265-1266页

作者： Fei Wang jian zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences

Styrene(ST)is one of the most important chemicals in the world because of its widely applications in the syntheses of rubbers or ***,ST is mainly produced through catalytic dehydrogenation of ethylbenzene(EB)and the product always contains large amount unreacted EB and by-products toluene(Tol)and benzene(Bz)[1].Because of the similar boiling points and sizes of these molecules,the separation of these mixtures to reach polymer-grade ST of 99.5%purity is extremely *** that complicated vacuum/extractive distillation process currently used in industry is highly energy-intensive[2],adsorption separation by using porous adsorbents is a promising alternative *** method can realize ultrahigh selectivity via molecular sieving ***,for complicated mixtures,co-adsorption of smaller molecules makes it difficult to achieve high adsorption selectivity[3].

关键词： separation adsorption selectivity

Functionally Oriented Tumor Microenvironment Responsive Polymeric Nanoassembly:Engineering and Applications

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Chinese Journal of Polymer Science 2018年第3期36卷 273-287页

作者： Wen-Ming zhang jian zhang Zhu Qiao Jun Yin Department of Polymer Science and Engineering School of Chemistry and Chemical EngineeringHefei University of Technology and Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei 230009China

The excellent drug encapsulation,prolonged in vivo circulation time,enhanced pharmacokinetics,and reduced adverse effects make the polymeric assemblies ideal carriers in nanomedicine,and become an emerging research field with rapid *** vivo,the polymer nanoassemblies will experience five steps,including circulation in the blood,accumulation in the tumoral site,penetration into the deep tumor tissue to reach cancer cells,internalization into cancer cells,and intracellular drug ***,although tremendous efforts have been made to the material design,currently available carriers still have difficulties in fulfilling all of the ***,the long-standing dilemma of the synchronized stability and permeability of vesicles is still a big challenge,which confused researchers for a long *** feature article tbcuses on the recent progress of single-or multi-stimuli triggered theranostic platforms,and the extracellularly reengineered shell-sheddable polymeric nanocarriers are systematically *** perspectives for future developments in the nanocarriers functioned with artificial helical polymers(the potential cell-penetrating peptides mimics)are also *** speculate that this feature article can fit the interesting of diverse readers and a guideline for the design of next generation of drug nanocarriers.

关键词： Block copolymers Tumor microenvironment responsive Self-assembly Theranostic Nanomedicine

Semi-unitary Transformation Induced Supersymmetric Partner Hulthen System

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Chinese Physics Letters 1996年第7期13卷 485-488页

作者： zhang Jiu-an MA Gui-rong zhang jian-zu Department of Physics Hebei Normal CollegeShijiazhuang 050091 Institute for Theoretical Physics East China University of Science and TechnologyShanghai 200237

The supersymmetric partner system of Hulthen system in the s state is obtained by using a semi-unitary *** physical foundation of applications of semi-unitary transformation to supersymmetric quantum mechanics is expl... 详细信息

关键词： unitary symmetric Transformation

Orientation Dependence of Stress Rupture Properties of a Ni-based Single Crystal Superalloy at 760℃

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Journal of Materials Science & Technology 2012年第3期28卷 229-233页

作者： Shaohua zhang Dong Wang jian zhang Langhong Lou Superalloys Division Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academyof Sciences72 Wenhua RoadShenyang 110016China

The orientation dependence of creep rupture lives of a single crystal superalloy at 760℃/760 MPa was *** orientations of the specimens tested were about 30°away from [001].The results showed that specimens with orientations on the [001]-[011] boundary had the longest rupture *** deformation of these specimen were controlled by a/2〈110〉 slip and a few stacking faults with two orientations were *** the other hand,specimens with orientations near the [001]-[011] boundary or on the [001]-[111] boundary showed short rupture lives,and stacking faults with single orientation were observed in these *** rupture properties and the deformation mechanisms were discussed based on the dislocation pattern and the calculated Schmid factors for different specimens.

关键词： Single crystal superalloy Stress rupture Orientation

Layered space time codes and capacity analysis in correlated fading channels with distributed antenna system

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 28-35页

作者： XIONG Fei zhang jian-hua zhang Ping Wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education 13eijing University of Posts and Telecommunications Beijing 100876 China

In this paper we have investigated the performance of downlink generalized distributed antenna system （GDAS）. Under the assumption of spatial correlated fading conditions, we have derived the numeric expression of correlated coefficients according to series of Bessel function, and have lifted the range restriction of the mean angle of incident. Moreover, the architecture of distributed generalized layered space time codes （GLST） has been considered in order to achieve both multiplexing gain and diversity gain while we have used basis vector from null space instead of orthogonal set to obtain the same system performance but with lower complexity. Furthermore, in order to maximize the capacity, Gerschgorin circles based fast antenna selection algorithms have been evaluated including a discussion of those simulation results.

关键词： GDAS GLST capacity correlated fading channel