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Distribution of glycerol ethers in Turpan soils:implications for use of GDGT-based proxies in hot and dry regions

Frontiers of Earth Science 2018年第4期12卷 862-876页

作者： Jingjie zang Yanyan LEI Huan YANG State Key Laboratory of Biogeology and Environmental Geology School of Earth SciencesChina University of GeoseiencesWuhan 430074China Department of Geology and Environmental Science University of PittsburghPittsburghPA 15260USA

Proxies based on glycerol dialkyl glycerol tetraethers (GDGTs), a suite of membrane lipids occurring ubiquitously in soils, have generated increasing interest in quantitative paleo-environmental reconstruction. Hot and dry climates are likely to have occurred in the geological past; however, the limitations and applicability of these proxies to hot and dry environments are still unknown. In this study, we analyzed the GDGT distribution in the Turpan (TRP) basin of China, where the highest soil temperature can be approximately 70°C, and the mean annual precipitation (MAP) is 15.3 mm. We compared GDGT-based proxies among TRP soils, Nanyang (NY) soils, and Kunming (KM) soils; these three sites exhibit similar mean annual air temperature (MAAT) albeit contrasting temperature seasonality and MAP. Archaeal isoprenoidal GDGTs (isoGDGTs) dominate over bacterial branched GDGTs (brGDGTs) in most TRP soils; this is a characteristic GDGT distribution pattern for soils from dry regions globally. Another feature is the anomalously high GDGT-0/crenarchaeol ratio, which is generally attributed to the contribution of anaerobic methanogenic archaea by previous studies; however, these anaerobic archaea are unlikely to be highly abundant in the dry TRP soils, indicating that certain uncultured halophilic Euryarchaeota are likely to produce a significant amount of GDGT-0 that finally results in a high GDGT-0/Cren ratio. The changes in the salinity of the TRP soils appear to be an important factor affecting the MBT’5ME and the relative abundance of 6- vs. 5-methyl pentamethylated brGDGTs (IRIIa’). This is likely to introduce certain scatters in the correlations between MBT’5ME and MAAT and that between IRIIa’ and pH determined at the global scale. A comparison of the MBT’5ME-inferred temperature between TRP, NY, and KM soils does not indicate a significant bias toward summer temperature, indicating that brGDGT paleothermometers in soils could reflect the MAAT.

关键词： GDGTs Turpan soils semi-arid and arid areas salinity MBT’5ME

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Problems and Suggestions for the Construction of China's Geographical Indication System

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学术界 2017年第2期 313-321页

作者： zang Xingdong Law School Chongqing University Law School Guizhou University

There are problems in the process of our GIs’construction,such as lack of enough promotion in the protection of traditional culture and ecological agriculture,effective interests balance mechanism between agribusiness and farmer,and so ***"territoriality"should be taken as the core essential factor and"embedded"into the process of industrialization of agriculture,ensure that the interests of the farmers be based on"territoriality"and obtain the sustainable development,promote the realization of agricultural industrialization and modernization in our country.

关键词：地理标志农业产业化中国生态农业可持续发展传统文化平衡机制农业企业

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Gold-Hydrogen Nanoclusters:Atom-Precise Model to Unveil Catalytic Mechanism and Growth Process of Gold Nanoparticles

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Chinese Journal of Chemistry 2020年第6期38卷 663-664页

作者： Zhao-Yang Wang Shuang-Quan zang College of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China

Gold nanoclusters show high catalytic performance in various chemical reactions including the hydrogenation and hydrogen evolution *** involved gold clusters is the ideal model to investigate the hydrogen-gold cluster interactions,the influence of H atoms on the electronic structures of the gold clusters,the particle growth process,and the catalytic *** paper highlights the pioneering experimental and theoretical works in the gold-hydrogen cluster studies,and overviews the existing challenges.

关键词： mechanism. clusters cluster

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A Novel Interacting Multiple-Model Method and Its Application to Moisture Content Prediction of ASP Flooding

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Computer Modeling in Engineering & Sciences 2018年第1期114卷 95-116页

作者： Shurong Li Yulei Ge Renlin zang Automation School Beijing University of Posts and TelecommunicationsBeijingChina College of Information and Control Engineering China University of Petroleum(East China)QingdaoChina

In this paper,an interacting multiple-model(IMM)method based on datadriven identification model is proposed for the prediction of nonlinear dynamic ***,two basic models are selected as combination components due to their proved *** is Gaussian process(GP)model,which can provide the predictive variance of the predicted output and only has several optimizing *** other is regularized extreme learning machine(RELM)model,which can improve the overfitting problem resulted by empirical risk minimization principle and enhances the overall generalization *** both of the models are updated continually using meaningful new data selected by data selection ***,recursive methods are employed in the two models to reduce the computational burden caused by continuous ***,the two models are combined in IMM algorithm to realize the hybrid prediction,which can avoid the error accumulation in the single-model *** order to verify the performance,the proposed method is applied to the prediction of moisture content of alkali-surfactant-polymer(ASP)*** simulation results show that the proposed model can match the process very *** IMM algorithm can outperform its components and provide a nice improvement in accuracy and robustness.

关键词： Interacting multiple model regularized extreme learning machine gaussian process moisture content of ASP flooding

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Crystal Structures and Electrochemical Properties of R1.5Ca1.5MgNi14(R=Nd, Gd and Er) Hydrogen Storage Alloys

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Chemical Research in Chinese Universities 2019年第6期35卷 1040-1045页

作者： zang Jiahe ZHANG Qing’an SUN Dalin School of Materials Science and Engineering Anhui University of TechnologyMaanshati 243002P.R.China Department of Materials Science Fudan UniversityShanghai 200433P.R.China

Ca3MgNi14,Nd1.5Ca1.5MgNi14,Gd1.5Ca1.5MgNi14 and Er1.5Ca1.5MgNi14 alloys were prepared by high frequency induction melting and *** and analysis were performed by X-ray diffraction/Rietveld full-spectrum fitting,gaseous P-C-T hydrogen storage test and electrochemical properties *** can be found that all alloys consist of Gd2Co7-type 3R phase and Ce2Ni7-type 2H *** the hydrogen storage capacities of Nd1.5Ca1.5MgNi14,Gd1.5Ca1.5MgNi14 and Er1.5Ca1.5MgNi14 decrease to some extent compared to that of Ca3MgNi14,their equilibrium pressures for absorption and desorption increase ***,R1.5Ca1.5MgNi14 alloys have better cycling stabilities and high-rate discharge(HRD)properties as compared to *** hydrogen diffusion in alloy electrodes is the main factor to influence the HRD performance.

关键词： Hydrogen storage alloy Crystal structure Electrochemical performance High-rate discharge Element substitution

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Feasibility study of creep feed grinding of 300M steel with zirconium corundum wheel

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Chinese Journal of Aeronautics 2022年第3期35卷 565-578页

作者： Jiaqiang DANG Heng zang Qinglong AN Weiwei MING Ming CHEN School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical Systems and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

The ultrahigh strength 300M steel has been commonly used in the manufacture of aircraft landing gear and rotor shaft parts due to its excellent mechanical *** feed grinding is one of the essential operations during the whole component manufacturing *** this work,the feasibility of creep feed grinding of 300M steel by using the hard zirconium corundum wheel was theoretically and experimentally evaluated.A variety of responses including grinding forces,temperature fields,specific grinding energy,surface integrity and chip modes were carefully ***,the mechanism of ground surface profile generation and the spatial frequency spectrum of the surface profile were tentatively *** was found that the wheel speed has a relative influence on the grinding forces and temperatures of which the work hardening effect dominates the material removal with lower wheel speed while the thermal softening becomes crucial as the wheel speed exceeds the critical value for the studied 300M ***,a scattered spatial frequency spectrum for the generated surface profile was noticed with lower wheel speed while the spectrum gathers towards the lower frequency values with higher amplitude as the wheel speed *** shearing chip and flowing chip dominates the main chip type,indicating the excellent abrasive sharpness during the grinding *** general,the used zirconium corundum wheel presents feasibility for the creep feed grinding of 300M steel because of the high material removal rate,absence of surface burn,low wheel wear and higher compressive residual stresses.

关键词： 300M steel Chip formation Creep feed grinding Surface morphology Zirconium corundum wheel

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Model for the Whole Roller Leveling Process of Plates with Random Curvature Distribution Based on the Curvature Integration Method

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Chinese Journal of Mechanical Engineering 2019年第3期32卷 145-155页

作者： Ben Guan Chao Zhang Yong zang Yuan Wang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China

A model based on the curvature integration method has been applied in an online plate leveling system. However, there are some shortcomings in the current leveling models. On the one hand, the models cannot deal with the leveling process of plates with a random curvature distribution. On the other hand, the current models are suitable only for stable leveling processes and ignore the biting in and tailing out stages. This study presents a new plate-leveling model based on the curvature integration method, which can describe the leveling process of plates with random curvature distribution. Further, the model is solved in two cases in order to take the biting in and tailing out stages into consideration. The proposed model is evaluated by comparing with a plate leveling experiment. Finally, the leveling process of a plate with a wave bent is studied using the proposed model. It is found that the contact angles vary greatly during the biting in and tailing out stages. However, they are relatively steady during the 5 roller leveling stage. In addition, the contact angle of roller No. 2 is the smallest, which is close to 0. Roller leveling can effectively eliminate bending in the plate, but there are regions in the head and tail of the plate, where roller leveling is not effective. The non-leveling region length is about 2 times that of the roller space. This study proposes a quasi-static plate-leveling model, which makes it possible to analyze the dynamic straightening process using a curvature integration method. It also makes it possible to analyze the straightening process of a plate with random curvature distribution.

关键词： Leveling Curvature integration method Curvature Contact angle Deflection

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Conjugate Heat Transfer Investigation on the Cooling Performance of Air Cooled Turbine Blade with Thermal Barrier Coating

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Journal of Thermal Science 2016年第4期25卷 325-335页

作者： JI Yongbin MA Chao GE Bing zang Shusheng School of Mechanical and Power Engineering Shanghai Jiaotong University

A hot wind tunnel of annular cascade test rig is established for measuring temperature distribution on a real gas turbine blade surface with infrared ***,conjugate heat transfer numerical simulation is performed to obtain cooling efficiency distribution on both blade substrate surface and coating surface for *** effect of thermal barrier coating on the overall cooling performance for blades is compared under varied mass flow rate of coolant,and spatial difference is also *** indicate that the cooling efficiency in the leading edge and trailing edge areas of the blade is the *** cooling performance is not only influenced by the internal cooling structures layout inside the blade but also by the flow condition of the mainstream in the external cascade *** barrier effects of the coating vary at different regions of the blade surface,where higher internal cooling performance exists,more effective the thermal barrier will be,which means the thermal protection effect of coatings is remarkable in these *** the designed mass flow ratio condition,the cooling efficiency on the pressure side varies by 0.13 for the coating surface and substrate surface,while this value is 0.09 on the suction side.

关键词： gas turbine blade thermal barrier coating cooling efficiency conjugate heat transfer

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Inverse Construction Methods of Heterogeneous NURBS Object Based on Additive Manufacturing

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Computer Modeling in Engineering & Sciences 2020年第11期125卷 597-610页

作者： Ting zang Dongbin Zhu Guowang Mu School of Science Hebei University of TechnologyTianjin300130China School of Mechanical Engineering Hebei University of TechnologyTianjin300130China

According to the requirement of heterogeneous object modeling in additive manufacturing(AM),the Non-Uniform Rational B-Spline(NURBS)method has been applied to the digital representation of heterogeneous object in this *** putting forward the NURBS material data structure and establishing heterogeneous NURBS object model,the accurate mathematical unified representation of analytical and free heterogeneous objects have been *** the inverse modeling of heterogeneous NURBS objects,the geometry and material distribution can be better designed to meet the actual *** Basis Function(RBF)method based on global surface reconstruction and the tensor product surface interpolation method are combined to RBF-NURBS inverse construction *** geometric and/or material information of regular mesh points is obtained by RBF interpolation of scattered data,and the heterogeneous NURBS surface or object model is obtained by tensor product *** examples have shown that the heterogeneous objects fitting to scattered data points can be generated effectively by the inverse construction methods in this paper and 3D CAD models for additive manufacturing can be provided.

关键词： NURBS heterogeneous object inverse construction method RBF scattered data points

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Tandem Strip Mill's Multi-parameter Coupling Dynamic Modeling Based on the Thickness Control

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Chinese Journal of Mechanical Engineering 2015年第2期28卷 353-362页

作者： PENG Yan ZHANG Yang SUN Jianliang zang Yong National Engineering Research Center for Equipment and Technology of Cold Rolling Strip Yanshan University School of Mechanical Engineering University of Science and Technology Beijing

The rolling process is determined by the interaction of a number of different movements,during which the relative movement occurs between the vibrating roll system and the rolled piece,and the roll system＇s vibration interacts with the strip＇s deformation and rigid *** many parameters being involved leads to a complex mechanism of this coupling *** testing and analyzing the vibration signals of the mill in the rolling process,the rolling mill＇s coupled model is established with comprehensive consideration of the coupling interaction between the mill＇s vertical vibration,its torsional vibration and the working roll＇s horizontal vibration,and vibration characteristics of different forms of rolling mill＇s vibration are analyzed under the coupling *** comprehensive attention to the relationship between the roll system,the moving strip and the rolling parameters＇dynamic properties,and also from the strip thickness control point of view,further research is done on the coupling mechanism between the roll system＇s movement and the moving strip＇s characteristics in the rolling *** a result,the law of inertial coupling and the stiffness coupling effect caused by different forms of the roll system＇s vibration is determined and the existence of nonlinear characteristics caused by the elastic deformation of moving strip is also ***,a multi-parameter coupling-dynamic model is established which takes the tandem strip mill as its research object by making a detailed kinematics analysis of the roll system and using the principle of virtual *** coupling-dynamic model proposes the instruction to describe the roll system＇s movement,and analyzes its dynamic response and working stability,and provides a theoretical basis for the realization of the strip thickness＇dynamic control.

关键词： tandem strip mill dynamic characteristics moving strip roll system

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