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A new approach of cascade utilization of the chemical energy of fuel

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Progress in Natural Science:Materials International 2006年第5期16卷 518-523页

作者： HAN Wei, JIN Hongguang and LIN Rumou ( Institute of Engineering Thermophysics, Chinese Academy of Sciences, beijing 100080, china {2. school of the Chinese Academy of Sciences, beijing 100080, china) [a]Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China [b]graduate school of the Chinese Academy of Sciences Beijing China

The indirect release of chemical energy of fuel is investigated, and a new mechanism is proposed to identify the cascade utilization of chemical energy of fuel more clearly. Based on the concept of energy level, the internal phenomenon of the indirect chemical energy release is disclosed, and the equations of energy level describing the utilization of chemical energy and thermal energy during the indirect chemical energy release process are obtained. From theoretical analysis, we find that the superiority of the indirect chemical energy release of fuel comes from the cascade utilization of the fuel's chemical energy. Moreover, the cascade utilization of chemical energy is verified by the investigation of CRGT (chemically recuperated gas turbine). As a result, the thermal exergy obtained from the chemical energy release of fuel increases by 2.% -3 % . The results obtained here may help a deeper understanding of indirect chemical energy release of fuel and provide a theoretical basis for the synthesis of innovative energy systems.

关键词： chemically recuperated gas turbine methane/steam reforming chemical energy level cascade utilization.

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological Sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2. GU Yidong3, LIN Baojun3 & GUO Jiong3 1. Center for Space Science and Applied Research, Chinese Academy of Sciences, beijing 100080, china 2. {2. school of the Chinese Academy of Sciences, beijing 10003., china 3. General Establishment of Space Science and Application, Chinese Academy of Sciences, beijing 100080, china Correspondence should be addressed to L Congmin 1. Center for Space Science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. graduate school of the Chinese Academy of Sciences 100039 Beijing China 3. General Establishment of Space Science and Application Chinese Academy of Sciences 100080 Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2.m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

Kinetics and reaction mechanism of phenol hydroxylation catalyzed by La-Cu_4FeAlCO_3

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Science china Chemistry 2005年第6期48卷 530-537页

作者： CHEN Chunxia1,2. XU Chenghua1, FENG Liangrong1, SUO Jishuan1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, china 2. graduate {2. of the Chinese Academy of Sciences, beijing 10003., china 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. graduate school of the Chinese Academy of Sciences 100039 Beijing China

The present work synthesizes La-Cu4FeAlCO3 catalyst under microwave irradiation and characterizes its structure using XRD and IR techniques. The results show that the obtained La-Cu4FeAlCO3 has a hydrotalcite structure. In the phenol hydroxylation with H2.2.catalyzed by La-Cu4FeAlCO3, the effects of reaction time and phenol/H2.2.molar ratio on the phenol hy-droxylation, and relationships between the initial hydroxylation rate with concentration of the catalyst, phenol, H2.2.and reaction temperature are also investigated in details. It is shown the phenol conversion can reach 50.09% (mol percent) in the phenol hydroxylation catalyzed by La-Cu4FeAlCO3, under the reaction conditions of the molar ratio of phenol/H2.2.1/2. the amount ratio of phenol/catalyst 2., reaction temperature 343 K, reaction time 12. min, 10 mL distilled water as solvent. Moreover, a kinetic equation of v = k[La ? Cu 4 FeAlCO 3 ][C 6 H 5 OH][H 2.O 2.. and the activation energy of Ea=58.37 kJ/mol are obtained according to the kinetic studies. Due to the fact that the HO-Cu+-OH species are detected in La-Cu4FeAlCO3/H2.2.system by XPS, the new mechanism about the generation of hydroxyl free radicals in the phenol hydroxylation is pro-posed, which is supposed that HO-Cu+-OH species are transition state in this reaction.

关键词： rare earth, hydrotalcite, microwave irradiation, phenol hydroxylation, kinetics, reaction mechanism.

Development of a Wire Driven Robot for Grinding with Stiffness Adapted

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厦门大学学报（自然科学版） 2002年第S1期41卷 81-82页

作者： ZHANG Bo 1,2. ZHAO Ming-yang 2.(1. graduate school of the Chinese Academy of Sciences,{2. , china 2. Robotics Laboratory, Shenyang Institute of Automation, Chinese Academy of S ciences, Shenyang 110016, china)

Along with development of new design and machining me thod production with more complex surface can be manufactured. Researching on th e new equipment used for surface disposal has become the important matter. Grind ing and polishing are a common surface processing method. A new type wire driven parallel robot used for grinding processing is proposed in this paper. Wire driven parallel robot is developed from parallel robot and serial wire driven r obot. Steel wire is used to replace the leg of parallel robot. Compared with par allel robot, this kind of robot has lager workspace, lower weight, higher rigidi ty and higher load/deadweight ratio. And the stiffness of robot is controlled by changing the tension of wire. The robot proposed in this paper has three DOF. T he moving part is driven by four wires, three of them are used to drive and the rest to keep them tension, with a restraining machine. The position sensors are installed in restraining machine. The position of terminating of end-effecter c an be ascertained in the space. The tension sensors are installed in each wire t o form force feedback system. By changing the tension the force on the workpiece can be controlled. Also the stiffness of robot can be adjusted.

关键词： wire driven parallel robot stiffness control

An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3 1 Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,beijing 100080,china 2.College of Chemistry and Chemical Engineering,{2. University of Chinese Academy of Sciences,beijing 100049,china 3 school of Chemical Engineering and Environment,beijing Institute of Technology,beijing 100081,china 1. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. school of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Possible Energy Network with polygeneration system and CCS for china

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中国科学：技术科学英文版 2010年第1期53卷 33-39页

作者： GAO Lin1,LI Sheng1,2.JIN HongGuang1 & LIN Hu1 1 Institute of Engineering Thermophysics,Chinese Academy of Sciences,beijing 100190,china 2.{2. school of Chinese Academy of Sciences,beijing 10003.,china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

On basis of adopting polygeneration systems for power and alternative fuels,capturing CO2.with near zero energy penalties,and storing CO2.on sites,a new kind of Energy Network can integrate energy utilization,CO2.capture,transportation and storage ***-economic analysis of this solution focusing on Inner Mongolia and the Yangtze River Delta districts had been carried with comparison to the chain method for energy utilization and CO2.*** solution can save 2..5% of energy,and reduce 35% of total *** adoption of advanced polygeneration systems contributes 52.2. of the total saved costs,and the integration of energy utilization and CO2.sequestration in the Energy Network contributes 47.8%.From the aspect of CCS,the CO2.sequestration cost in the Energy Network can be as low as 12.$/t due to the lower energy penalties of capture in polygeneration systems and the combination of CO2.source and *** Energy Network exhibits attractive performance on energy saving,costs reduction for CCS,which may be a promising solution for sustainable development of china.

关键词： CO2 capture and storage Energy Network polygeneration system

Overexpression of a tobacco small G protein gene NtRop1 causes salt sensitivity and hydrogen peroxide production in transgenic plants

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Science china(Life Sciences) 2008年第5期51卷 383-390页

作者： CAO YangRong1,2. LI ZhiGang1,2. CHEN Tao1,2. ZHANG ZhiGang1, ZHANG JinSong1 & CHEN ShouYi1 1 National Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, beijing 100101, china 2.{2. school of Chinese Academy of Sciences, beijing 10003., china 1. National Key Lab of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China 2. graduate school of Chinese Academy of Sciences Beijing 100039 China

The small GTPases of Rop/Rho family is central regulators of important cellular processes in plants. Tobacco small G protein gene NtRop1 has been isolated; however, its roles in stress responses were unknown. In the present study, the genomic sequence of NtRop1 was cloned, which has seven exons and six introns, similar to the Rop gene structure from Arabidopsis. The NtRop1 gene was constitutively expressed in the different organs whereas the other six Rop genes from tobacco had differential expression patterns. The expression of the NtRop1 gene was moderately induced by methyl viologen, NaCl, and ACC treatments, but slightly inhibited by ABA treatment, with no significant induction by NAA treatment. The transgenic Arabidopsis plants overexpressing the NtRop1 showed increased salt sensitivity as can be seen from the reduced root growth and elevated relative electrolyte leakage. The hydrogen peroxide production was also promoted in the NtRop1-trangenic plants in comparison with wild type plants. These results imply that the NtRop1 may confer salt sensitivity through activation of H2.2.production during plant response to salt stress.

关键词： small G protein NtRop1 salt sensitive hydrogen peroxide

Prediction method for October 2.03 solar storm

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Science china(Technological Sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2. 3, WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, beijing 100080, china 2. {2. school, Chinese Academy of Sciences, beijing 10003., china 3. Institute of Meteorology, PLA University of Science and Technology, Nanjing 2.1101, china State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China graduate school Chinese Academy of Sciences Beijing 100039 China Institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 2. and 2., 2.03, this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Characterization of a sodium-regulated glutaminase from cyanobacterium Synechocystis sp. PCC 6803

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Science china(Life Sciences) 2008年第12期51卷 1066-1075页

作者： ZHOU Jie1, ZHOU JunXia1,2. YANG HaoMeng1, YAN ChengShi1 & HUANG Fang1 1 Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, beijing 100093, china 2.{2. school of Chinese Academy of Sciences, beijing 10003., china 1. Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. graduate school of Chinese Academy of Sciences Beijing 100039 China

Glutaminase is widely distributed among microorganisms and mammals with important functions. Lit-tle is known regarding the biochemical properties and functions of the deamidating enzyme glutami-nase in cyanobacteria. In this study a putative glutaminase encoded by gene slr2.79 in Synechocystis sp. PCC 6803 was investigated. The slr2.79 was expressed as histidine-tagged fusion protein in Es-cherichia coli. The purified protein possessed glutaminase activity, validating the functional assign-ment of the genomic annotation. The apparent Km value of the recombinant protein for glutamine was 2..6 ± 0.9 mmol/L, which was comparable to that for some of other microbial glutaminases. Analysis of the purified protein revealed a two-fold increase in catalytic activity in the presence of 1 mol/L Na+. Moreover, the Km value was decreased to 12.2.± 1.9 mmol/L in the presence of Na+. These data demon-strate that the recombinant protein Slr2.79 is a glutaminase which is regulated by Na+ through in-creasing its affinity for substrate glutamine. The slr2.79 gene was successfully disrupted in Synecho-cystis by targeted mutagenesis and the △slr2.79 mutant strain was analyzed. No differences in cell growth and oxygen evolution rate were observed between △slr2.79 and the wild type under standard growth conditions, demonstrating slr2.79 is not essential in Synechocystis. Under high salt stress condition, however, △slr2.79 cells grew 1.2.-fold faster than wild-type cells. Moreover, the photosyn-thetic oxygen evolution rate of △slr2.79 cells was higher than that of the wild-type. To further charac-terize this phenotype, a number of salt stress-related genes were analyzed by semi-quantitative RT-PCR. Expression of gdhB and prc was enhanced and expression of desD and guaA was repressed in △slr2.79 compared to the wild type. In addition, expression of two key enzymes of ammonium assimi-lation in cyanobacteria, glutamine synthetase (GS) and glutamate synthase (GOGAT) was examined by semi-quant

关键词： cyanobacteria Synechocystis putative glutaminase enzyme activity mutagenesis salt tolerance