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Demand-driven water withdrawals by Chinese industry： a multi-regional input-output analysis

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Frontiers of Earth Science 2016年第1期10卷 13-28页

作者： bo ZHANG Z. M. chen l. ZENG H. QIAO b. chen School of Management China University of Mining & Technology (Beijing) Beijing 100083 China State Key l.b.ratory of Coal Resources and Safe Mining China University of Mining & Technology (Beijing) Beijing 100083 China School of Economics Renmin University of China Beijing 100872 China State Key l.b.ratory of Simulation and Regulation of Water Cycle in River basin China Institute of Water Resources and Hydropower Research Beijing 100038 China School of Management University of Chinese Academy of Sciences Beijing 100190 China State Key Joint l.b.ratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

With ever increasing water demands and the continuous intensification of water scarcity arising from China＇s industrialization, the country is struggling to harmonize its industrial development and water supply. This paper presents a systems analysis of water with- drawals by Chinese industry and investigates demand- driven industrial water uses embodied in final demand and interregional trade based on a multi-regional input-output model. In 2007, the Electric Power, Steam, and Hot Water Production and Supply sector ranks first in direct industrial water withdrawal （DWW）, and Construction has the largest embodied industrial water use （EWU）. Investment, consumption, and exports contribute to 34.6%, 33.3%, and 30.6% of the national total EWU, respectively. Specifically, 58.0%, 51.1%, 48.6%, 43.3%, and 37.5% of the regional EWUs respectively in Guangdong, Shanghai, Zhejiang, Jiangsu, and Fujian are attributed to international exports. The total interregional import/export of embodied water is equivalent to about 40% of the national total DWW, of which 55.5% is associated with the DWWs of Electric Power, Steam, and Hot Water Production and Supply. Jiangsu is the biggest interregional exporter and deficit receiver of embodied water, in contrast to Guangdong as the biggest interregional importer and surplus receiver. Without implementing effective water- saving measures and adjusting industrial structures, the regional imbalance between water avail.b.lity and water demand tends to intensify considering the water impact of domestic trade of industrial products. Steps taken to improve water use efficiency in production, and to enhance embodied water saving in consumption are both of great significance for supporting China＇s water policies.

关键词： water withdrawal embodied water use Chinese industry interregional trade multi-regional inputoutput analysis

An Engineering Application Tool for Visual Assessment of the Equil.b.ium beach

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China Ocean Engineering 2007年第4期21卷 701-713页

作者： T.l.lEE D.S.JENG b.R.chen Department of Construction Technology Leader UniversityTainan 709China Division of Civil Engineering School of EngineeringPhysics and MathematicsUniversity ofDundeeDD1 4HNScotlandU.K. Department of Resource and Environment Leader UniversityTainan 709China

An engineering application tool for prediction of the static equil.b.ium bay （ beach Mod） is established to describe two bay shape formulas by use of the programming software ＂MATl.b. with a graphic user interface （ GUI）. The tool is user-friendly for engineering students for the design of beach shapes. This tool was tested through application on three types of beaches in Taiwan and Australia. by implementing the concept of Headland Control, the beach Mod program allows users to draw a structure and create an ＇artificial headland. The results indicate that beach Mod can efficiently forecast beach changes as well as MEPbAY, a competing software package, while boasting a better user interface.

关键词： prediction static equil.b.ium bay MATlAb graphic user interface

STUDY ON VERTICAl WATER TEMPERATURE MODEl FOR MIYUN RESERVOIR

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Journal of Hydrodynamics 2000年第4期12卷 75-83页

作者： li, Y.l. chen, Y.C. Zhang, b.X. Dep. of Hydraulic Eng. Tsinghua Univ. Beijing 100084 China

According to the characters of the Miyun reservoir located in northeast beijing, one-dimensional method is used to establish a mathematical model of temperature for the reservoir. In this model the heat exchange between water surface and atmosphere, effective diffusion, inflows, outflows, and thermal advection are considered comprehensively. The effective diffusion coefficient, decay coefficient of short wave in water, etc, are cal.b.ated based on the observed stratification data of 1991 in the reservoir. The mathematical model is verified through the agreement with the data of 1992. This model can be used to predict the temperature distribution along the vertical direction for the Miyun reservoir and other similar reservoir.

关键词： Computer simulation Heat transfer Mathematical models Temperature distribution

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina Hromada Patrick Heimel Markus Kerbl lászlóGál Sylvia Nürnberger barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes C.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller David Hercher Department life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria ludwig boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the avail.b.lity of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model.b.t not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

SIMUlATION OF lARGE TURbINE ROTOR'S HEAT TREATMENT PROCESS

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Acta Metallurgica Sinica(English letters) 2005年第6期18卷 768-772页

作者： C. Jiang Y.b. chen b.S. Wu Q.l. Jin beijing Research Institute of Mechanical and Electrical Technology Beijing 100083 China

Temperature field numerical simulation about he heat treatment process curve of large turbine rotor is presented. With simulation software Deform3D in according to the heat treatment processing of China First Heavy Machinery, the details of temperature change at the different location of the rotor is to be found. Once knowing the temperature field change, the duplex grain defect long time existed in large forgings can be solved with a quantitative analysis instead of only the qualitative one. Precondition for small metal samples is brought to simulate microstructare and grain size change of large rotor according to the numerical simulation result. Also, consistent feature with real manufacture is showed from the physical experiment, so that the simulation can be used to not only improve the products process but also prevent wasting unnecessary energy and shorten process periods. The rotor quality is controlled thoroughly with plenty of experiments data.

关键词： temperature field numerical simulation grain size

Mitigating methodology of hardware non-ideal characteristics for non-volatile memory based neural networks

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Science China(Information Sciences) 2025年

作者： lixia HAN Peng HUANG Yijiao WANG Zheng ZHOU Haozhang YANG Yiyang chen Xiaoyan lIU Jinfeng KANG School of Integrated Circuits Peking University beijing Advanced Innovation Center for Integrated Circuits School of Integrated Circuit Science and Engineering Beihang University

Non-volatile memory-based computing-in-memory (nvCIM) paradigm has been extensively studied to boost the energy efficiency of neural network accelerators in edge ***,the degradation of inference accuracy induced by the non-ideal characteristics across circuits,arrays,and devices is becoming a crucial *** this work,we establish a hardware characteristic behavior model to analyze the impact of nvCIM non-ideal characteristics on neural network *** we propose a hardware aware training and weight mapping correction methods to mitigate inference accuracy *** simulation verification,about 95%inference accuracy degradation is recovered by adopting the proposed mitigation method for various non-ideal characteristics and various neural network *** feasibility of the proposed method is further proved in an experimental example with a flash-based leNet recognition system.

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Stable copper boron–imidazolate cage as Cu-riched enzyme for highly efficient electrocatalytic CO2 reduction to ethylene

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Science China Chemistry 2025年

作者： Jun-Qiang chen Qiao-Hong li Qin-long Hong Ping Shao Hai-Xia Zhang Jian Zhang State Key l.b.ratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Single-atom catalyst has garnered widespread attention to mimic mature enzymes due to its well-defined atomic structure and coordination environments. However, since the carbon–carbon（C–C） coupling reactions require synergistic catalysis of multiple sites, single-atom catalysts suffer from insufficient active sites and unclear reaction mechanisms. Controlling the reaction intermediates in a precisely targeted pocket through careful metal–organic cage design is therefore crucial. Here, we prepare a tetrahedral [Cu6l4]-type boron–imidazolate cage integrating highly active Cu sites and optimized cavity, which exhibits enzyme like specific catalytic performance in electrochemical CO2reduction reaction（CO2RR） to enhance the selectivity of *** analyses and computational calculations suggest that the single Cu site together with neighboring boron–imidazolate ligands provides suitably synergistic effects that enable the energetically favorable formation of an *COCHO intermediate, a key step determining selectivity. As a result, the [Cu6l4]-type cage of bIC-145 achieves a Faradaic efficiency of 28% for C2H4maintaining an average current density of -3.54 mA cm-2over a 5-hour electrolysis period. This work represents the first example for studying single-metal site catalysts with ultra-low coordination numbers through the rational design of metal–organic cages.

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lung-targeted polyzwitterionic lipid nanoparticles for effective treatment of lung inflammation

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Science China Chemistry 2025年

作者： Wen Zhang Jiaxin li Nan Wang Muzi li chen Peng Xinyue Zhang Guanghui Ouyang Yan li beijing Key l.b.ratory for bioengineering and Sensing Technology School of Chemistry and Biological Engineering University of Science and Technology Beijing CAS Key l.b.ratory of Colloid Interface and Chemical Thermodynamics Institute of Chemistry Chinese Academy of Sciences

lipid nanoparticles (lNPs) are non-viral nucleic acid delivery systems that show great potential in vaccine development and disease treatment. Although lNPs are particularly advantageous for in vivo delivery, the wide application of lNPs is impeded as their systemic delivery of nucleic acid drugs to extrahepatic tissues remains highly challenging. To address this issue, we developed lung-targeted polyzwitterionic lNPs with zwitterionic polymer poly(2-methyacryloyloxyethyl phosphorylcholine)(PMPC) modified 1,2-dimyristoyl-sn-glycerol lipid for the delivery of small interfering RNA (siRNA). Three l.b.aries with 90PMPC-lNPs@siRNA were established. The polyzwitterionic PMPC-lNPs had high siRNA encapsulation efficiency of about90%. The findings revealed that polyzwitterionic PMPC-lNPs@siRNA absorbed protein corona with the main component of Vitronectin, mediating lung-targeted delivery of siRNA. With good cellular uptake and endo/lysosomal escape ability, in vitro and in vivo studies demonstrated that polyzwitterionic PMPC-lNPs with siRNA against tumor necrosis factor-α (TNF-α) could significantly down-regulate the TNF-α in mRNA and protein levels, and improved the pathological features of lung inflammation. Polyzwitterionic PMPC-lNPs@siRNA achieved safe and efficient treatment of lung inflammation. Therefore, this work offered a promising siRNA therapeutic approach for lung diseases.

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Static and Dynamic Properties of Soil Food Web Structure in a Greenhouse Environment

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Pedosphere 2014年第2期24卷 258-270页

作者： chen Yun-Feng CAO Zhi-Ping l.POPESCU b.H.KIEPPER Institute of Plant Protection and Soil Fertilizer Hubei Academy of Agricultural Sciences College of Resources and Environmental Science China Agricultural University Department of biological and Agricultural Engineering University of Georgia

Soil food web structure is fundamental to ecosystem process and function; most studies on soil food web structure have focused on agro-ecosystems under different management practices and natural terrestrial ecosystems,but seldom on greenhouses. This study explored the static and temporal variability of soil food structure in two greenhouses of Shandong Province,North China over a two-year period. The static properties were measured directly by surveying functional group composition and a series of parameters portraying the species properties,link properties,chain properties and omnivory properties of the web,as well as indirectly through calculation of nematode indices,enrichment index(EI),structure index(SI),and channel index(CI). The dynamic variability of greenhouse soil food structure was described by the dynamics of functional groups,bray-Curtis(bC) similarity and cluster analysis. The results showed that the greenhouse soil food web contained 14 functional groups,with microbes having the highest mean biomass,followed by protozoa. Of the three functional groups of protozoa,flagellates were the dominant group on most sampling dates,amoebae only became the dominant group during the summer,while ciliates were the least prevalent group. All nematodes were assigned into one of the four functional groups,bacterivorous,fungivorous,herbivorous and omnivorous,and the fungivorous nematodes had the lowest mean biomass. Mites were assigned into three functional groups and the omnivorous noncryptostigmatic mites were the dominant group. All the functional groups showed significant seasonal changes. The soil food web connectance was 0.15,the maximum food chain length was 5,and the average food chain length was 3.6. The profiles of the EI and SI showed that the food web was resourcedepleted with minimal structure. The results of CI indicated that the bacterial decomposition pathway was the dominant pathway in the food web of the greenhouse soils studied and the results of bC

关键词： bray-Curtis similarity functional group mites nematodes protozoa