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Design of policy mechanism to promote cleaner production in China

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Journal of environmental sciences 2001年第3期13卷 346-350页

作者： ZHANG Tian zhu(department of environmental {2. and engineering, tsinghua university, beijing 100084, China. department of environmental {2. and engineering Tsinghua University Beijing 100084 China. zhangtz@***

In order to promote cleaner production in China, a package of policy options was presented based on the identification of the barriers encountered in the CP demonstration project and the effectiveness and feasibility of policy options for the CP implementation were analyzed. Furthermore, the policy mechanism framework was given, which composes of compulsory, economic incentive, social pressure and supportive function. Finally, the implementation strategy of the policy mechanism, in which the emphasis will be changed from compulsory policy options towards economic and social pressure policy options, was proposed.

关键词： cleaner production barrier identification policy mechanism China

Expression of lignin peroxidase H2.from Phanerochaete chrysosporium by multi-copy recombinant Pichia strain

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Journal of environmental sciences 2009年第2期21卷 218-222页

作者： WANG Wei,WEN Xianghua department of environmental {2. and engineering,tsinghua university,beijing 100084,China. department of environmental {2. and engineering Tsinghua University Beijing 100084 China

The lipH2.gene, encoding the expression of lignin peroxidase, was cloned from Phanerochaete chrysosporium BKM-F-1767 and expressed in Pichia pastoris X-33, a yeast. The cDNA of LiPH2.was generated from total RNA extracted from P chrysosporium by PCR with primers that do not contain a P. chrysosporium lignin peroxidase secretion signal. The gene was then successfully inserted into the expression vector pPICZα, and resulted in the recombinant vector pPICZα-lipH2. The transformation was conducted in two ways. One was using the wild Pichia pastoris as the recipients, which results in the recombinant P. pastoris with single or low lipH2.gene copy. The second was using P. pastoris and single or low lipH2.gene copy as the recipients, which results in the recombinant P. pastoris with multi-copies of lipH2.genes. This study firstly expressed the gene lipH2.in P. pastoris and achieved the successful expression of the lipH2.depending upon the generation of a recombinant strain that contained multiple copies. The lignin peroxidase activity reached a maximum of 15 U/L after 12.h induction.

关键词： heterologous expression lignin peroxidase Pichia pastoris

Biogas recovery from microwave heated sludge by anaerobic digestion

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science China(Technological sciences) 2010年第1期53卷 144-149页

作者： QIAO Wei1,WANG Wei2.ZHU CuiPing3 & ZHANG ZhongZhi1 1 College of Chemical science and engineering,China {2. of Petroleum,beijing 102.49,China 2.department of environmental science and engineering,tsinghua university,beijing 10084,China 3 J & K China Cleaning Energy Technology Co.Ltd.,beijing 100085,China 1. College of Chemical science and engineering China University of Petroleum Beijing 102249 China2. Department of Environmental Science and Engineering Tsinghua University Beijing 10084 China3. J & K China Cleaning Energy Technology Co. Ltd. Beijing 100085 China

Biogas generated from sewage sludge,livestock waste,and food waste by anaerobic digestion is a valuable renewable energy ***,conventional anaerobic digestion is not an efficient process.A long hydraulic retention time and low biogas recovery rate hinder the applications of those *** effective pretreatment method to destroy sludge microbial cells has been one of the major concerns regarding improvement of the biogas *** article focuses on the effects of microwave heating on sludge anaerobic *** suspended solid(VSS) and chemical organic demand solubilization of heated sludge were *** heating was found to be a rapid and efficient process for releasing organic substrates from *** increase of organic dissolution ratio was not obvious when holding time was over 5 min with microwave *** effect of the VSS solubilization was primarily dependent on heating *** highest value of VSS dissolving ratio,36.4%,was obtained at 170°C for 30 *** COD dissolving ratio was about 2.% at 170°*** organic carbon of treated sludge liquor was 1.98 and 2.73 g/L at 150°C and 170°C for 5 min,respectively.A biochemical methane potential(BMP) test of excess sludge and a mixture of primary and excess sludge demonstrated an increase in biogas *** total biogas from microwave treated mixture sludge increased by 12.9% to 2..2. over control after 30 days of *** production was 11.1% to 2..9% higher for excess sludge than for untreated *** VS removal ratios of mixture sludge and excess sludge were 12. and 11% higher,respectively,compared to the untreated sludge.

关键词： biogas recovery microwave heating sludge anaerobic digestion

Gas kinetic algorithm for flows in Poiseuille-like microchannels using Boltzmann model equation

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science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 496-512页

作者： LI Zhihui1,2. ZHANG Hanxin1 & FU Song2.⒈ National Laboratory for CFD, Hypervelocity Aerodynamics Institute,China Aerodynamics Research and Development Center,Mianyang 62.000,China 2.department of engineering Mechanics,{2.,beijing 100084,China 1. National Laboratory for CFD Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development Center 621000 Mianyang China 2. department of engineering Mechanics Tsinghua University 100084 Beijing China

The gas-kinetic unified algorithm using Boltzmann model equation have been extended and developed to solve the micro-scale gas flows in Poiseuille-like micro-channels from Micro-Electro-Mechanical Systems (MEMS). The numerical modeling of the gas kinetic boundary conditions suitable for micro-scale gas flows is presented. To test the present method, the classical Couette flows with various Knudsen numbers, the gas flows from short microchannels like plane Poiseuille and the pressure-driven gas flows in two-dimensional short microchannels have been simulated and compared with the approximate solutions of the Boltzmann equation, the related DSMC results, the modified N-S solutions with slip-flow boundary theory, the gas-kinetic BGK-Burnett solutions and the experimental data. The comparisons show that the present gas-kinetic numerical algorithm using the mesoscopic Boltzmann simplified velocity distribution function equation can effectively simulate and reveal the gas flows in microchannels. The numerical experience indicates that this method may be a powerful tool in the numerical simulation of micro-scale gas flows from MEMS.

关键词： Boltzmann model equation, discrete velocity ordinate method, finite-difference scheme, Couette flow, Poiseuille flow, gas flow in short-microchannel.

Estimation of methane and nitrous oxide emissions from biomass waste in China:A case study in Hebei Province

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science China(Technological sciences) 2010年第1期53卷 19-23页

作者： LUO YuXiang1,WANG Wei1,WAN Xiao2.DENG Zhou2.& ZHU CuiPing2.1 department of environmental {2. and engineering,tsinghua university,beijing 10084,China 2.J&K China Cleaning Energy Technology Company Limited,beijing 100085,China 1. department of environmental {2. and engineering Tsinghua University Beijing 10084 China2. J&K China Cleaning Energy Technology Company Limited Beijing 100085 China

Crop residue,animal manure and MSW are selected as representative biomass *** gas emissions from treatment and disposal process of biomass waste in Hebei province are estimated for the period from 2.02.to 2.07,using the methodologies recommended by the Intergovernmental Panel on Climate *** gas emission was about 10 Mt CO2.equivalent *** 6% of greenhouse gas emission came from open burning of crop residue,74% from management system of animal manure,and 2.% from MSW *** all the greenhouse gas sources,landfill is the most concentrated one,and has significant potential of emission reduction.

关键词： biomass waste methane nitrous oxide IPCC methodology

To enhance the reproduction of Phanerochaete chrysosporium by adding natural lixiviums in liquid medium

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Journal of environmental sciences 2003年第6期15卷 808-814页

作者： LIN Gang, WEN Xiang-hua, QIAN Yi (department of environmental {2. and engineering, tsinghua university, beijing 100084, China. department of environmental {2. and engineering Tsinghua University Beijing 100084 Chin

Great promotion to the reproduction of white rot fungus Phanerochaete chrysosporium by adding natural lixiviums such as from wood, maize core and potato in liquid medium was found in this research. Incubated in the liquid medium contained 10 mg/L glucose as carbon source with natural lixiviums for three days, the production of mycelium pellet reaches more than 80 g/L, which is 5 times more than that of without natural lixiviums. Incubated in the liquid medium contained 5 mg/L glucose as carbon source with natural lixiviums for three days, the production of mycelium pellet can reach 69.5 g/L, while the production in the medium without natural lixiviums is very low. When the liquid medium contained 1—2. g/L glucose as carbon source, the production of mycelium pellet in 3 d can only reach 12.5 g/L to 14.5 g/L. The fungus in the medium with potato lixiviums are easily contaminated by other microorganisms and in the medium with maize core lixiviums are easily bulking, while in the medium with wood lixiviums are neither easily contaminated nor bulking. Medium with wood lixiviums can produce more pellet than other medium, endure contamination and keep better sedimentation capacity. So that, wood lixivium is better additive to the culture of white rot fungi in liquid medium. Addition of the mixture of wood, maize core and potato lixiviums is of advantage to the production of mycelium pellet. The difference of the production in the medium with different amount of wood lixiviums showed little in the first 3 d, while it expanded after 3 d. Wood lixiviums stimulate the growth of P. chrysosporium instead of supply organics which fungi need.

关键词： white rot fungi medium additive

Parameter estimation for whole-body kinetic model of FDG metabolism

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Progress in Natural science:Materials International 2006年第11期16卷 1164-1170页

作者： CUI Yunfeng~1, BAI Jing~1**, CHEN Yingmao~2.and TIAN Jiahe~2.1. department of Biomedical engineering, {2., beijing 100084, China 2. department of Nuclear Medicine, General Hospital of PLA, beijing 100853, China) [a]department of Biomedical engineering Tsinghua University Beijing China [b]department of Nuclear Medicine General Hospital of PLA Beijing China

Based on the radioactive tracer [ ~ 18 F]2.fluoro-2.deoxy-D-glucose （FDG）, positron emission tomography （PET）, and compartment model, the tracer kinetic study has become an important method to investigate the glucose metabolic kinetics in human body. In this work, the kinetic parameters of three-compartment and four-parameter model for the FDG metabolism in the tissues of myocardium, lung, liver, stomach, spleen, pancreas, and marrow were estimated through some dynamic FDG-PET experiments. Together with published brain and skeletal muscle parameters, a relatively complete whole-body model was presented. In the liver model, the dual blood supply from the hepatic artery and the portal vein to the liver was considered for parameter estimation, and the more accurate results were obtained using the dual-input rather than the single arterial-input. The established whole-body model provides the functional information of FDG metabolism in human body. It can be used to further investigate the glucose metabolism, and also be used for the simulation and visualization of FDG metabolic process in human body.

关键词： compartment model FDG PET parameter estimation.

A new orthogonality relationship for orthotropic thin plate theory and its variational principle

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science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 371-380页

作者： LUO Jianhui 1 , LONG Yuqiu 2.& LIU Guangdong 1 1. College of Civil engineering, Hunan university, Changsha 410082. China 2. {2. of Civil engineering, tsinghua university, beijing 100084, China 1. College of Civil engineering Hunan University 410082 Changsha China 2. department of Civil engineering Tsinghua University 100084 Beijing China

The thought how dual vectors are constructed in a new orthogonality relationship for theory of elasticity is generalized into orthotropic thin plate bending problems by using the analogy theory between plane elasticity problems and plate bending problems. Dual differential equations are directly obtained by using a mixed variables method. A dual differential matrix to be derived possesses a peculiarity of which principal diagonal sub-matrixes are zero matrixes. Two independently and symmetrically orthogonality sub-relationships are discovered. By using the integral form for elastic bending theory of orthotropic thin plate the orthogonality relationship is demonstrated. By selecting felicitous dual vectors a new orthogonality relationship for theory of elasticity can be generalized into elastic bending theory of orthotropic thin plate. By using the integral form a variational principle which is relative to differential form and a whole function expression are proposed.

关键词： theory of elasticity, thin plate theory, dual vectors, orthogonality relationship, orthotropic, variational principle.

Improvement of the classification accuracy in discriminating diabetic retinopathy by multifocal electroretinogram analysis

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Progress in Natural science:Materials International 2007年第8期17卷 913-918页

作者： Xu Jin~1 Hu Guangshu~(1**) Huang Houbin~2.(1.department of Biomedical engineering,{2.,beijing 100084,China 2.department of Ophthalmology,General Hospital of Chinese PLA,beijing 100853,China) [a]department of Biomedical engineering Tsinghua University Beijing China [b]department of Ophthalmology General Hospital of Chinese PLA Beijing China

The multifocal electroretinogram (mfERG) is a newly developed electrophysiological *** this paper,a classifi- cation method is proposed for early diagnosis of the diabetic retinopathy using mfERG *** records were obtained from eyes of healthy individuals and patients with diabetes at different *** each mfERG record,103 local responses were *** value of each point on all the mfERG local responses was looked as one potential feature to classify the experimental *** sub- sets were selected from the feature space by comparing the inter-intra *** on the selected feature subset,Fisher's linear classi- fiers were *** the final classification decision of the record was made by voting all the classifiers' *** the method to classify all experimental subjects,very low error rates were *** crucial properties of the diabetic retinopathy classification method are also discussed.

关键词： diabetic retinopathy multifocal electroretinogram feature selection linear classifier