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| 1 | Review on hidden trouble detection and health diagnosis of hydraulic concrete structures显示文摘A large number of hydraulic concrete structures have hidden defects such as cracks, erosion, freeze and thaw, thermal fatigue, carbonization. These hidden defects seriously affect the strength, stability and durability of structures. These problems are studied mainly by single monitoring or diagnosis methods at present. The integration of multiple monitoring and diagnosis methods is not applied widely. Besides, the analysis theory on these problems is not developed very well. The systemic study on the aging mechanism of hydraulic concrete structures, time- variation model and health diagnosis is still not enough. The support for engineering practice is limited. Aimed at these major scientific and technological problems and combined with specific projects, study on detection of hidden defects and health diagnosis of hydraulic concrete structure has been carried out. This study includes the following content: field non-destructive examination of hidden defects of hydraulic concrete structures, seepage detection, the construction of in-situ sensing system, the combination of field detection and in-situ monitoring, the mechanism of crack, freeze and thaw, erosion and carbonization of hydraulic concrete structure, mechanism of combination aging; time-variation model of hydraulic concrete structure, theories and methods for health diagnosis of hydraulic concrete structures. | WU ZhongRu1,2?, LI Ji1, GU ChongShi1,2 & SU HuaiZhi1,2 1 College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Nanjing 210098, China | 2007 | Science China(Technological Sciences)2007，50，z1： | 27 |
| 2 | Antisense to cyclin D1 reverses the transformed phenotype of human gastric cancer cells显示文摘INTRODUCTIONStudiesonthefunctionsofcelularprotooncogenesandtumorsuppresorgenesindicatethatmostofthesegenesmediatesignaltrans... | CHEN Bing 1, ZHANG Xue Yong 2, ZHANG Yu Jing 3, ZHOU Ping 3, GU Yan 4 and FAN Dai Ming 2 | 1999 | World Journal of Gastroenterology1999，5，1： | 23 |
| 3 | Expression of insulin-like growth factor Ⅱ and its receptor in liver cells of chronic liver diseases显示文摘ExpressionofinsulinlikegrowthfactorⅡanditsreceptorinlivercelsofchronicliverdiseasesYANGDongHua1,XIUChong1,YANGBo1,GUJianR... | YANG Dong Hua 1, XIU Chong 1, YANG Bo 1, GU Jian Ren 2, QIAN Lian Fang 2 and QU Shu Ming 2 | 1997 | World Journal of Gastroenterology1997，3，2： | 21 |
| 4 | Effects of hypoxia,hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 in hepatic stellate cells显示文摘AIM To study the effects of hypoxia, hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 (MMP-2) in hepatic stellate cells ( HSC).``METHODS The expressions of MMP-2, tissue inhibitor of mjatrix metalloproteinese-2 ( TIMP-2 ) and membrane type matrix metalloproteiness-l (MT1-MMP) in cultured rat HSC were detected by immunocytochemistry (ICC) and in situ hybridization (ISH). The contents of MMP-2 and TIMP-2 in culture supernatant were detected with ELISA and the activity of MMP-2 in supematant was revealed by zymography.``RESULTS In the situation of hypoxia for 12 h, the expression of MMP-2 protein wss enhenced (hypoxiagroup positive indexes: 5.7 ± 2.0, n = 10; control: 3.2 ±1 .0. n -- 7; P<0.05). while TIMP-2 protein wss decreased in HSC ( hypoxia group positive indexes: 2.5 ± 0.7, n =10: control: 3.6 ± 1.0, n = 7; P | Ping-Sheng Chen~(1,2) Wei-Rong Zhai~1 Xiao-Mei Zhou~3 Jin-Sheng Zhang~1 Yue-E Zhang~1 Yu-Qin Ling~1 Ying-Hong Gu~1 1 Department of Pathology,School of Basic Medical Sciences,Fudan University,Shanghai 200032,China2 Ping-Sheng Chen now works in the Department of Pathology,School of Basic Medical Sciences the (former Nanjing Railway Medical College),Southeast University,Nanjing 210009,China3 Institute of Cancer Research,Shanghai 200032,China | 2001 | World Journal of Gastroenterology2001，7，5： | 18 |
| 5 | Recent research and applications of GPS based technology for bridge health monitoring显示文摘Today,long-span bridges are being designed to be more flexible and to resist extensive impacts from changes in temperature,severe wind gusts and earthquake tremors. Structural responses (especially displacement) of bridge structures are becoming increasingly important for the finite element (FE) modal updating,structural response prediction and safety evaluation. Methods of global displacement sensing were developed for these needs. This paper presents an overview of current research and development activities in the field of bridge health monitoring using the global positioning system (GPS). The GPS monitoring technology and its accuracy assessment method are also briefly described. Finally,existing problems and promising research efforts in the GPS based bridge health monitoring are discussed. | YI TingHua1,2, LI HongNan1 & GU Ming2 1 Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 116023, China 2 State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China | 2010 | Science China(Technological Sciences)2010，53，10： | 18 |
| 6 | Sedimentary geochemistry of the Cambrian-Ordovician cherts: Implication on archipelagic ocean of North Qilian orogenic belt显示文摘The Caledonian North Qilian orogenic belt lies between the North China plate and the Qaidam mi-croplates, and resulted from the collision among the Qaidam microplate, mid-Qilian block and the North China plate. The orogen initiated from the rifting of the Late Proterozoic Rodinia, and then it experi-enced stages of Cambrian rift basin and Ordovician archipelagic oceanic basin, and foreland basin during Silurian to Early-Middle Devonian. The average ratios of Al/(Al+Fe+Mn), Al/(Al+Fe), δ Ce, Lan/Ybn and Lan/Cen from cherts of Cambrian Heicigou Formation are 0.797, 0.627, 1.114, 0.994 and 1.034 re-spectively. In the NAS standardized REE distribution pattern, the cherts from Xiangqianshan is slightly HREE enriched, and the cherts from Ganluci and Shiqingdong are plane. All of these features indicated that Cambrian cherts of the Heicigou Formation originated from a continental margin rift background. On the contrary, the average ratios of Al/(Al+Fe+Mn), Al/(Al+Fe), δ Ce, Lan/Ybn, Lan/Cen of the Ordovician chert from Dakecha, Cuijiadun, Shihuigou, Laohushan, Heicigou, Maomaoshan, Bianmagou, Da-chadaban, Baiquanmen, Jiugequan and Angzanggou, are respectively 0.72, 0.58, 0.99, 1.09 and 0.96 respectively. Their NAS standardized REE distribution patterns of most Ordovician cherts are plane mode or slightly HREE enriched. The REE distribution pattern of few samples of cherts are slightly LREE enriched. Characteristics of sedimentary geochemistry and tectonic evolution demonstrated that the Cambrian-Ordovician cherts, associated with rift, oceanic, island arc and back-arc volcanic rocks, was not formed in a typical abyssal oceanic basin or mid-oceanic ridge. On the contrary, they formed in a deepwater basin of continental margin or a archipelagic ocean tectonic setting. Several Early Paleo-zoic ophiolite belts in North Qilian and adjacent periphery Qaidam microplate imply that an archipelagic ocean during Ordovician existed in the east of Pro-Tethys. | DU YuanSheng1,2, ZHU Jie1, GU SongZhu1, 2, XU YaJun1 & YANG JiangHai1 1 Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China 2 Key Laboratory of Biogeology and Environment Geology of Education Ministry, Wuhan 430074, China | 2007 | Science China Earth Sciences2007，50，11： | 17 |
| 7 | An Anthropomorphic Robot Hand Developed Based on Underactuated Mechanism and Controlled by EMG Signals显示文摘When developing a humanoid myo-control hand,not only the mechanical structure should be considered to afford a highdexterity,but also the myoelectric (electromyography,EMG) control capability should be taken into account to fully accomplishthe actuation tasks.This paper presents a novel humanoid robotic myocontrol hand (AR hand Ⅲ) which adopted an underac-tuated mechanism and a forearm myocontrol EMG method.The AR hand Ⅲ has five fingers and 15 joints,and actuated by threeembedded motors.Underactuation can be found within each finger and between the rest three fingers (the middle finger,the ringfinger and the little finger) when the hand is grasping objects.For the EMG control,two specific methods are proposed:thethree-fingered hand gesture configuration of the AR hand Ⅲ and a pattern classification method of EMG signals based on astatistical learning algorithm-Support Vector Machine (SVM).Eighteen active hand gestures of a testee are recognized ef-fectively,which can be directly mapped into the motions of AR hand Ⅲ.An on-line EMG control scheme is established basedon two different decision functions:one is for the discrimination between the idle and active modes,the other is for the recog-nition of the active modes.As a result,the AR hand Ⅲ can swiftly follow the gesture instructions of the testee with a time delayless than 100 ms. | Da-peng Yang~1 Jing-dong Zhao~1 Yi-kun Gu~1 Xin-qing Wang~1 Nan Li~1 Li Jiang~1Hong Liu~(1,2) Hai Huang~3 Da-wei Zhao~41.State Key Laboratory of Robotics and System,Harbin Institute of Technology,Harbin 150001,P.R.China2.Institute of Robotics and Mechatronics,German Aerospace Center,Munich 82230,Germany3.College of Shipbuilding Engineering,Harbin Engineering University,Harbin 150001,P.R.China4.College of Automation,Harbin Engineering University,Harbin 150001,P.R.China | 2009 | Journal of Bionic Engineering2009，6，3： | 16 |
| 8 | Preliminary study on the production of transgenic mice harboring hepatitis B virus X gene显示文摘INTRODUCTIONDespiteoverwhelmingepidemiologicalevidencelinkingpersistentHepatitisBVirus(HBV)infectionandthedevelopmentofhepato... | ZHU Huan Zhang 1, CHENG Guo Xiang 2, CHEN Jian Qu 2, KUANG Shu Yuan 3, CHENG Yong 2, ZHANG Xin Li 1, Ll Hou Da 2, XU Shao Fu 2, SHI Jing Quan 1, QIAN Geng Sun 3 and GU Jian Ren 3 | 1998 | World Journal of Gastroenterology1998，4，6： | 14 |
| 9 | Spatial patterns of terrestrial net ecosystem productivity in China during 1981―2000显示文摘As the third largest country in the world, China has highly variable environmental condition and eco- logical pattern in both space and time. Quantification of the spatial-temporal pattern and dynamic of terrestrial ecosystem carbon cycle in China is of great significance to regional and global carbon budget. In this study, we used a high-resolution climate database and an improved ecosystem process-based model to quantify spatio-temporal pattern and dynamic of net ecosystem productivity (NEP) in China and its responses to climate change during 1981 to 2000. The results showed that NEP increased from north to south and from northeast to southwest. Positive NEP (carbon sinks) occurred in the west of Southwest China, southeastern Tibet, Sanjiang Plain, Da Hinggan Mountains and the mid-west of North China. Negative NEP (carbon sources) were mainly found in Central China, the south of Southwest China, the north of Xinjiang, west and north of Inner Mongolia, and parts of North China. From the 1980s to 1990s, the increasing trend of NEP occurred in the middle of Northeast China Plain and the Loess Plateau and decreasing trends mainly occurred in a greater part of Central China. In the study period, natural forests had minimal carbon uptake, while grassland and shrublands accounted for nearly three fourths of the total carbon terrestrial uptakes in China during 1981―2000. | TAO Bo1, CAO MingKui1, LI KeRang1, GU FengXue1, JI JinJun1,2, HUANG Mei1 & ZHANG LeiMing1 1 Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2 Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100101, China | 2007 | Science China Earth Sciences2007，50，5： | 12 |
| 10 | Large eddy simulation of flow in a street canyon with tree planting under various atmospheric instability conditions显示文摘In this work, a large eddy simulation (LES) model, which includes momentum and heat source (or sink) inside the tree planting layer, is proposed for the simulation of flow in a street canyon with tree planting. Vegetation canopy layer simulation shows that this model can be used to simulate the velocity distribution and temperature variation inside the canopy layer. Effects of atmospheric instability on flow and pollutant distribution in a street canyon with tree planting of an aspect ratio of 0.5 are studied. Results show that compared with the canyon with no tree planting (or the exposed street canyon), the canyon with tree planting shows a reduced wind circulation and pollutant exchange rate (PER) at the top layer of the street canyon, which induces the increase in the pollutant concentrations near road surface, leeward wall and windward wall. When street canyon atmosphere is under a strongly unstable condition, wind velocity decreases while pollutant concentration is increased in the areas near the street canyon top, road surface, leeward and windward walls, compared with the wind velocity in the street canyon with the neutral stratification. When street canyon atmosphere is under a weakly unstable condition, wind velocity weakens near the street canyon top and windward wall, but strengthens near the road surface and leeward wall, and pollutant concentration is decreased near the leeward and windward walls and is increased between the two rows of trees. When the street canyon atmosphere is under an unstable condition, PER is lower than that under the neutral stratification. | GU ZhaoLin1, ZHANG YunWei2 & LEI KangBin3 1 School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, China 1 School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China 3 RIKEN Institute, Wako, Saitama, 351-0198, Japan | 2010 | Science China(Technological Sciences)2010，53，7： | 10 |
| 11 | HJ-1A HSI on-orbit radiometric calibration and validation research显示文摘The calibration experiment data at Dunhuang radiometric calibration site in October, 2008 were used to achieve the on-orbit radiometric calibration for HJ-1A hyper spectral imager (HSI). Two other field experiments data were used to validate the Dunhuang calibration results. One field experiment took place in Inner-Mongolia, China in September, 2008, and the other field experiment took place in Lake Frome, Australia in February, 2009. Finally, the ‘confidence interval of calibration error’ concept was put forward for quantitatively computing the calibration coefficient error confidence interval. The results showed that the Dunhuang calibration results in 2008 had high reliability. The confidence intervals of calibration error for all HSI channels were between 2% to 12%, which could satisfy the requirement of the HSI quantitative applications. | GAO HaiLiang1,2,3*, GU XingFa1,3*, YU Tao1,3, GONG Hui1,2,3, LI JiaGuo1,2,3 & LI XiaoYing1,3 1 State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100039, China 3 Center for National Spaceborne Demonstration, Beijing 100101, China | 2010 | Science China(Technological Sciences)2010，53，11： | 10 |
| 12 | Back analysis of mechanical parameters of roller compacted concrete dam显示文摘In view of the diversity and complexity of mechanical parameters of roller compacted concrete dam(RCCD),the uniform design method,partial least-squares regression(PLS)and least squares support vector machine(LSSVM)were applied to the back analysis of RCCD with the use of the complex nonlinear relationship between dam mechanical parameters and dam displacements.During the process of back analysis,the initial samples of parameters were designed with uniform design method.Then,a transversely isotropic model of RCCD was established by MSC.Marc software.Through this model,training samples of LSSVM model could be obtained.And then,the complex nonlinear relationship between relative values of hydraulic components of dam displacements and mechanical parameters was established.Finally,actual relative values of dam hydraulic components are isolated from the measured data of dam displacements by using PLS.By inputting the isolated relative values into LSSVM model,the back analysis values of RCCD mechanical parameters can be obtained.The example analysis showed that mechanical parameters obtained by the above-mentioned back analysis method are reasonable,and the back analysis method is feasible. | GU ChongShi 1,2,3,LI Bo 1,XU GuangLei 4 &YU Hong 1,2,3 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2College of Water Conservancy Hydropower,Hohai University,Nanjing 210098,China 3National Engineering Research Center of Water Resources Engineering Safety,Efficient Utilization and Nanjing 210098,China 4 Nanjing Hydraulic Research Institute,Nanjing 210029,China | 2010 | Science China(Technological Sciences)2010，53，3： | 8 |
| 13 | Influence of IFNα-2b and BCG on the release of TNF and IL-1 by Kupffer cells in rats with hepatoma显示文摘INTRODUCTIONKupffer cells are residential macrophages in the liver ,which play a critical role in the maintenance of normal liver function and in immunal surveilance of hepatocellular carcinoma (HCC) and other cancers[1].The biological immune modulants have cancers[2].In our previous studies ,the combined use of biological immune modulants showed better dffects . | Xian Yong Bai~1 Xiu Hong Jia~2 Ling Zhong Cheng~3 Yun Di Gu~3 ~1Department of Histology and Embryology,Binzhou Medical College,Binzhou 256603,Shandong Province,China ~2Departrnent of Pediatrics,Binzhou Medical College,Binzhou 256603,Shandong Province,China ~3Department of Histology and Embryology,Shanghai Medical University,Shanghai 200032,ChinaDr.Xian Yong Bai graduated from the Shanghai Medical University as a postgraduate in 1995,Professor of Histology and Embryology,specialized in hepatic tumor immunology,having 36 papers published. | 2001 | World Journal of Gastroenterology2001，7，3： | 7 |
| 14 | A brief account on the study of the insulin crystal structure In retrospect:Forty years after the determination of insulin’s crystal structure by Chinese scientists显示文摘'Standards there as high as achieved elsewhere';news delivered to the world by Science in China Approximately forty years ago when China was undergoing a period of great difficulty, Science in China, | WANG Da-Cheng1 & GU XiaoCheng2 1 National Laboratory of Macromolecules,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China 2 College of Life Sciences,Peking University,Beijing 100871,China | 2010 | Science China(Life Sciences)2010，53，1： | 6 |
| 15 | Morphology and reaction force of toes of geckos freely moving on ceilings and walls显示文摘The 3-dimensional interactions between toes of a gecko and substrates (ceilings or walls) were measured when it moves on ceilings or walls by using a 3-dimensional force measuring array,and the correspondent morphology of the gecko toes was recorded by a high speed camera.The study aims to understand the relationship between adhesive and shear forces generated by the toes of the gecko and the locomotion behavior when it walks on walls and ceilings.Results showed that shear force is along the toe-only 12.6° and 3.1° away from the toe for wall-climbing and ceiling-crawling,respectively while the adhesion is big enough to balance the body weight and moment.The shear forces generated by the first and the fifth toes are in opposite directions;this redundant force increases the reliability of adhesion and stability of locomotion.The support angles of toes are equal approximately for ceiling-crawling and wall-climbing.The study greatly inspires the design of a gecko-like robot. | WANG ZhouYi1,2,GU WenHua1,2,WU Qiang1,2,JI AiHong1 & DAI ZhenDong1 1 Institute of Bio-inspired Structure and Surface Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China 2 College of Mechanical and Electrical Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China | 2010 | Science China(Technological Sciences)2010，53，6： | 6 |
| 16 | A new method of estimating the equivalent elastic modulus of RCCD显示文摘Based on the composite material mechanic theory, the analysis method for the equivalent elastic moduli which are parallel and vertical to the construction interface of RCCD is studied in this paper. The differences between the equivalent elastic moduli which are vertical to the construction interface of RCCD gotten from different methods are discussed in detail. The variation range of the equivalent elastic modulus which is vertical to the construction interface of RCCD is studied based on the principle of minimum complementary energy and the principle of minimum potential energy. The effect of the related influential factors on the equivalent elastic modulus is analyzed. The estimation formula of the equivalent modulus which is vertical to the construction interface of RCCD is proposed. The feasibility of the approach proposed in this paper is analyzed through an example. | GU ChongShi1,2?, WU Yuan1, SU HuaiZhi1,2 & TANG LiHui1 1 College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Nanjing 210098, China | 2007 | Science China(Technological Sciences)2007，50，z1： | 6 |
| 17 | VEGF-specific siRNAs modified with 2′-deoxy effectively suppress VEGF expression and inhibit growth of nasopharyngeal carcinoma xenograft in a mouse model显示文摘Vascular endothelial growth factor (VEGF) is up-regulated in the vast majority of human tumors. The up-regulation of VEGF not only plays important roles in tumor angiogenesis, but also provides a target for tumor treatment with small interfering RNA (siRNA) that targets VEGF; however, it is unclear whether a quite high up-regulation of VEGF will affect the efficiency of RNA interference strategies targeting VEGF. A high level expression of VEGF was found in CNE cells from a nasopharyngeal carcinoma cell line. In this study, we investigate whether VEGF-specific siRNAs can effectively suppress VEGF expression in CNE cells, and study the methods for the use of VEGF-specific siRNAs as potential therapeutic agents. CNE cells with high VEGF expression induced by hypoxia were transfected with VEGF-specific siRNAs. The expression of VEGF was effectively suppressed by VEGF-specific siRNAs, measured by ELISA, Western blot analysis and RT-PCR. Furthermore, experiments in nude mice bearing nasopharyngeal carcinoma xenograft were initiated 5 d after injection of CNE cells. VEGF-specific siRNAs were modified with 2′-deoxy, then injected into the tumors, and a liposome-mediated siRNA transfection system and ultrasound exposure were used to help delivery of the siRNAs. Tumor growth was reduced significantly after 3 weeks' treatment. These studies suggest that VEGF-specific siRNAs still can effectively suppress VEGF expression even in tumor cell lines with a relatively high level of VEGF expression, such as CNE, and VEGF-specific siRNAs modified with 2′-deoxy can be used as potential agents for tumor therapy. | CHEN ShanYi1, GAO GuoFeng1, CHEN Wei1, Lü Qing2, TANG Shen2, HUA Zhong2, YE WenBin2, GU DaYong2, WANG ShaYan1 & ZHANG YaOu2 1 Shenzhen People’s Hospital, Clinical Medical College of Jinan University, Shenzhen 518020, China 2 Life Science Division, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China | 2008 | Science China(Life Sciences)2008，51，2： | 6 |
| 18 | Metallogenic dynamics of the Yimen-type copper deposits and prediction of concealed ores显示文摘1 Geology and origin of the Yimen-type copper deposits THE Yimen copper mining district is located in a rift environment on the margins of the Yangtze continent and occurs in the middle segment of the Wuding-Yimen-Yuanjiang fault depression zone in theProterozoic Kunyang rift, with the Lujijiang fault as the boundary in the west and the Luoci-Yimen faultas the boundary in the east, and in the north it borders on the Luwu copper ore field and in the south itlinks with the Yuanjiang copper deposit, thus constituting an SN-striking elongated basin. Exposed in themining district are mainly the Heishantou, Dalongkou, Meidang, Yingming, Luoxue, Elachang and Lujijiang formations of the Early-Middle Proterozoic Kunyang Group, constituting a suite of lightly metamorphic rocks of low greenschist facies, and locally the Debadu Formation-complexes of the Early Proterozoic-Archean Dahongshan Group. The mining district can be divided into two ore zones: the east ore zone andthe west ore zone. Mainly distributed in the west ore zone are the volcano-sedox-strongly reworked-deepsource superimposed-type ( Fengshan-type) ore deposits, including the Sanjiachang ( including theShishan and Fengshan copper deposits), Yiduochang, Elachang, Tianxing and Meishan copper deposits(occurrences) which are all designated to the typical Yimen-type copper deposits. In the east ore | HAN Rensheng~1, SUN Jiacong~1, GU Xiaochun~2, LI Jun~1, LI Yuan~1, LI Wei~1 and MA Deyun~1 1. Kunming University of Science and Technology, Kunming 650093, China 2. Yimen Mining Bureau, Yimen 651101, China | 1999 | Chinese Science Bulletin1999，44，S2： | 5 |
| 19 | Hydroisomerization of n-heptane over bimetal-bearing H_3PW_(12)O_(40) catalysts supported on dealuminated USY zeolite显示文摘The bimetal-bearing (CePt or LaPt) 12-tungstophosphoric acid (H3PW12O40 (PW)) catalysts supported on dealuminated USY zeolite (DUSY) were prepared by impregnation and characterized by XRD, BET, IR, and H2-chemisorption. Their catalytic activities were tested in the hydroisomerization of n-heptane with a continuous atmospheric fixed-bed reactor. After the steam treatment combined with the acid leaching, as well as the supporting with PW and the bimetals, the DUSY support retains the Y zeolite porosity and the PW well keeps its Keggin structure in catalysts. The doping of Ce into the catalysts enhances the dispersion of Pt on the catalyst surface. The Pt-bearing PW catalysts doped with Ce or La, especially Ce, exhibit much higher catalytic activity and selectivity than the catalysts without dopants at lowered reaction temperatures. At the optimal reaction conditions, i.e., the reaction temperature of 250℃ and WHSV of 1.4 h1, the catalyst with a Pt loading of 0.4%, PW loading of 10% and a molar ratio of Ce to Pt of 15:1 shows a conversion of n-heptane of 70.3% with a high selectivity for isomerization products of 94.1%. | WEI RuiPing1,2, GU YanBo1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing Uni- versity of Technology, Nanjing 210009, China 2 College of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China | 2008 | Science China Chemistry2008，51，2： | 5 |
| 20 | Application analysis of empirical mode decomposition and phase space reconstruction in dam time-varying characteristic显示文摘In view of some courses of the time-varying characteristics processing in the analysis of dam deformation,the paper proposes a new method to analyze the dam time-varying characteristic based on the empirical mode decomposition and phase space reconstruction theory.First of all,to reduce the influences on the traditional statistical model from human factors and assure the analysis accuracy,response variables of the time-varying characteristic are obtained by the way of the empirical mode decomposition;and then,a phase plane of those variables is reconstructed to investigate their processing rules.These methods have already been applied to an actual project and the results showed that data interpretation with the assists of empirical mode decomposition and phase space reconstruction is effective in analyzing the perturbations of response variables,explicit in reflecting the entire development process,and valid for obtaining the evolution rules of the time-varying characteristic.This methodology is a powerful technical support for people to further master the rules of dam operation. | ZHANG ZhiJun1,2,3,GU ChongShi1,2,BAO TengFei1,2,ZHANG Lan1,2 & YU Hong1,2 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Hohai University,Nanjing 210098,China 3 Department of Civil,Environmental and Geomatic Engineering,Swiss Federal Institute of Technology,Zurich 8093,Switzerland | 2010 | Science China(Technological Sciences)2010，53，6： | 4 |
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