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1MICROSTRUCTURAL MODEL OF GATORIZED WASPALOY IN THE ISOTHERMAL FORGING PROCESS显示文摘A microstructural model, which was to predict the evolution of microstructure of Gatorized Waspeloy in the isothermal forcing process, was developed in terms of dynamic recrystallization and grain growth. Three steps of experiment were conducted during developing the model: (1) .Specimens were compressed in M FS testing machine; (2) Dynamic recrystallization and grain growth were discussed; (3) Dynamic recrys- tallization model and grain growth mode were set up. The agreement of simulated results and experimental data is fine.J.P. Hu (Chongqing Iron and Steel Designing Research Institute, Chongqing 400013, China) J. Y. Zhuang, J.H. Du, Q. Deng, D. Feng and Z. Y. Zhong (Central Iron and Steel Research Institute, Beijing 100081, China) P. Janschek and J. Kramer (Thyssen Umformte 2001Acta Metallurgica Sinica(English Letters)2001,14,3:61
2New development thoughts on the bio-inspired intelligence based control for unmanned combat aerial vehicle显示文摘Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and hazardous,is very promising for the technological leadership of the nation and essential for improving the security of society.On the basis of introduction of bioinspired intelligence and UCAV,a series of new development thoughts on UCAV control are proposed,including artificial brain based high-level autonomous control for UCAV,swarm intelligence based cooperative control for multiple UCAVs,hy-brid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV,and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles(UCGVs).The exact realization of the proposed new development thoughts can enhance the effectiveness of combat,while provide a series of novel breakthroughs for the intelligence,integration and advancement of future UCAV systems.DUAN HaiBin 1 ,SHAO Shan 2 ,SU BingWei 3 &ZHANG Lei 41 State Key Laboratory of Science and Technology on Holistic Flight Control,School of Automation Science and Electrical Engineering, Beijing University of Aeronautics and Astronautics,Beijing 100191,China 2 Flight Control Department,Shenyang Aircraft Design and Research Institute,Shenyang 110035,China 3 Beijing Institute of Near Space Vehicle’s System Engineering,Beijing 100076,China 4Integration and Project Section,Air Force Equipment Academy,Beijing 100085,China 2010Science China(Technological Sciences)2010,53,8:32
3Impact of postoperative omega-3 fatty acid-supplemented parenteral nutrition on clinical outcomes and immunomodulations in colorectal cancer patients显示文摘AIM: To investigate the effect of omega-3 fatty acid parenteral supplementation postoperatively on clinical outcomes and immunomodulation in colorectal cancer patients. METHODS: Forty-two patients undergoing radical colorectal cancer resection with an indication for total parenteral nutrition postoperatively were enrolled in this prospective, double-blind, randomized, controlled study. Patients received total parenteral nutrition supplemented with either soybean oil (LCT; Intralipid, Fresenius-Kabi, SO group, n = 21) or a combination of omega-3 fish oil and soybean oil (LCT:fish oil = 5:1, fish oil; Omegaven, Fresenius-Kabi, FO group, n = 21), up to a total of 1.2 g lipid/kg per day for 7 d postoperatively. A same volume calorie and nitrogen was administrated. Routine blood test, biochemistry, systemic levels of IL-6 and TNF-α, percentage of CD3+, CD4+, and CD8+ lymphocytes were evaluated preoperatively and on postoperative d 1 and 8. Patient outcome was evaluated considering mortality during the hospital stay, length of postoperative hospital stay, and occurrence of infectious complications. RESULTS: Both lipid regimens were well tolerated. No differences between the two groups were noticed in demographics, baseline blood test, biochemistry, serum levels of IL-6 and TNF-α, percentage of CD4+, CD8+ lymphocytes, and ratios of CD4+/CD8+. Compared with those on postoperative d 1, serum IL-6 levels onpostoperative d 8 were significantly depressed in the FO group than in the reference group (-44.43 ± 30.53 vs -8.39 ± 69.08, P = 0.039). Simultaneously, the ratios of CD4+/CD8+ were significantly increased in the FO group (0.92 ± 0.62 vs 0.25 ± 1.22, P = 0.035). In addition, depression of serum TNF-α levels (-0.82 ± 2.71 vs 0.27 ± 1.67, P = 0.125) and elevation of CD3+ and CD4+ lymphocyte percentage (12.85 ± 11.61 vs 3.84 ± 19.62, P = 0.081, 17.80 ± 10.86 vs 9.66 ± 17.55, P = 0.084, respectively) were higher in the FO group than in the reference group. Patients in the FO group trended to need a shorter postoperative hospital stay (17.45 ± 4.80 d vs 19.62 ± 5.59 d, P = 0.19). No statistically significant difference was found when stratified to mortality and occurrence of infectious complications. CONCLUSION: Postoperative supplementation of omega-3 fatty acids may have a favorable effect on the outcomes in colorectal cancer patients undergoing radical resection by lowering the magnitude of inflammatory responses and modulating the immune response.Bin Liang, Shan Wang, Ying-Jiang Ye, Xiao-Dong Yang, You-Li Wang, Jun Qu, Qi-Wei Xie, Mu-Jun Yin, Division of Surgical Oncology and Division of Gastroenterological Surgery, Peking University People’s Hospital, Beijing 100044, China Author contributions: Liang B and Wang S contributed equally to this work Liang B and Wang S designed the research Liang B, Ye YJ, Yang XD, Wang YL, Qu J, Xie QW, Yin MJ performed the research and collected the data Wang S and Ye YJ supervised the research Liang B and Ye YJ analyzed the data Liang B wrote the paper and revised the manuscript. 2008World Journal of Gastroenterology2008,14,15:31
4Investigation of the 5.12 Wenchuan Earthquake damages to the Zipingpu Water Control Project and an assessment of its safety state显示文摘On May 12, 2008, a major earthquake measured 8 on the Richter scale jolted Wenchuan County in Si- chuan Province, China with the epicentral intensity of XI degrees. Zipingpu Dam is located 17.17 km from the epicenter and the influence intensity at the damsite reached IX―X degrees. It is the first time in the world for such a high concrete-faced rockfill dam (CFRD) in China to experience such a strong earthquake occurring in such a short distance. Due to its location of special importance to the down- stream areas, the safety state and damaging condition of the Zipingpu Dam has attracted great atten- tions from various circles. Based on site investigation of the damages to the Zipingpu Dam and com- parison analysis of the observation data obtained before and after the earthquake, the paper makes a comprehensive assessment of the key technical issues relevant to this high CFRD, including its safety state and the high slope stability after the earthquake.GUAN ZhiCheng Water Resources and Hydropower Planning & Design General Institute, Beijing100120, China 2009Science China(Technological Sciences)2009,52,4:26
5Ultrasonically activated scalpel versus monopolar electrocautery shovel in laparoscopic total mesorectal excision for rectal cancer显示文摘AIM: To investigate the feasibility and safety of monopolar electrocautery shovel (ES) in laparoscopic total mesorectal excision (TME) with anal sphincter preservation for rectal cancer in order to reduce the cost of the laparoscopic operation, and to compare ES with the ultrasonically activated scalpel (US). METHODS: Forty patients with rectal cancer, who underwent laparoscopic TME with anal sphincter preservation from June 2005 to June 2007, were randomly divided into ultrasonic scalpel group and monopolar ES group, prospectively. White blood cells (WBC) were measured before and after operation, operative time, blood loss, pelvic volume of drainage, time of anal exhaust, visual analogue scales (VAS) and surgery-related complications were recorded. RESULTS: All the operations were successful; no one was converted to open procedure. No significant differences were observed in terms of preoperative and postoperative d 1 and d 3 WBC counts (P = 0.493, P = 0.375, P = 0.559), operation time (P = 0.235), blood loss (P = 0.296), anal exhaust time (P = 0.431), pelvicdrainage volume and VAS in postoperative d 1 (P = 0.431, P = 0.426) and d 3 (P = 0.844, P = 0.617) between ES group and US group. The occurrence of surgery-related complications such as anastomotic leakage and wound infection was the same in the two groups. CONCLUSION: ES is a safe and feasible tool as same as US used in laparoscopic TME with anal sphincter preservation for rectal cancer on the basis of the skillful laparoscopic technique and the complete understanding of laparoscopic pelvic anatomy. Application of ES can not only reduce the operation costs but also benef it the popularization of laparoscopic operation for rectal cancer patients.Bao-Jun Zhou, Wei-Qing Song, Qing-Hui Yan, Jian-Hui Cai, Feng-An Wang, Jin Liu, Guo-Jian Zhang, Guo-Qiang Duan, Zhan-Xue Zhang, Department of Gastrointestinal Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China Author contributions: Zhou BJ, Song WQ, Yan QH, Cai JH, Wang FA, Liu J, Zhang GJ, Duan GQ and Zhang ZX contributed equally to this work Zhou BJ, Song WQ, Yan QH, Cai JH and Wang FA designed the research Zhou BJ, Liu J and Zhang GJ performed the research Duan GQ and Zhang ZX analyzed the data and Zhou BJ, Song WQ and Yan QH wrote the paper. 2008World Journal of Gastroenterology2008,14,25:25
6城市导视系统设计显示文摘城市导视系统设计是指一个完整的城市指示系统,包括行政交通导视系统、商业导视系统、文化旅游导视系统等。城市导视系统系统是城市形象和城市功能的重要组成部分,其合理设计和运用不仅可以使城市生活更加便利,而且也是使城市具有魅力的形象塑造。本文对国内国际上的优秀案例进行分析,并就城市导视系统设计的功能、审美特征以及实施方法进行了探讨。City design Institute,Central Academy of Fine Art,Beijing 100009) 2004城市发展研究2004,11,1:24
7Aerodynamic/Stealthy/Structural Multidisciplinary Design Optimization of Unmanned Combat Air Vehicle显示文摘An optimization strategy is proposed to deal with the aerodynamic/stealthy/structural multidisciplinary design optimization(MDO) issue of unmanned combat air vehicle(UCAV).In applying the strategy,the MDO process is divided into two levels,i.e.system level optimization and subsystem level optimization.The system level optimization is to achieve optimized system objective(or multi-objective) through the adjustment of global external configuration design variables.The subsystem level optimization consists of the aerodynamic/stealthy integrated design and the structural optimization.The aerodynamic/stealthy integrated design aims at achieving the minimum aerodynamic drag coefficient under the constraint of stealthy requirement through the adjustment of local external configuration design variables.The structural optimization is to minimize the structural weight by adjusting the dimensions of structural components.A flowchart to implement this strategy is presented.The MDO for a flying-wing configuration of UCAV is employed to illustrate the detailed process of the optimization.The results indicate that the overall process of the surrogate-based two-level optimization strategy can be implemented automatically,and quite reasonable results are obtained.Hu Tianyuan,Yu Xiongqing Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China 2009Chinese Journal of Aeronautics2009,22,4:21
8Sorafenib inhibits growth and metastasis of hepatocellular carcinoma by blocking STAT3显示文摘AIM: To investigate the inhibitory role and the underlying mechanisms of sorafenib on signal transducer and activator of transcription 3 (STAT3) activity in hepatocellular carcinoma (HCC).METHODS: Human and rat HCC cell lines were treated with sorafenib. Proliferation and STAT3 dephosphorylation were assessed. Potential molecular mechanisms of STAT3 pathway inhibition by sorafenib were evaluated. In vivo antitumor action and STAT3 inhibition were investigated in an immunocompetent orthotopic rat HCC model.RESULTS: Sorafenib decreased STAT3 phosphorylationat the tyrosine and serine residues (Y705 and S727), but did not affect Janus kinase 2 (JAK2) and phosphatase shatterproof 2 (SHP2), which is associated with growth inhibition in HCC cells. Dephosphorylation of S727 was associated with attenuated extracellular signal-regulated kinase (ERK) phosphorylation, similar to the effects of a mitogen-activated protein kinase (MEK) inhibitor U0126, suggesting that sorafenib induced S727 dephosphorylation by inhibiting MEK/ERK signaling. Meanwhile, sorafenib could also inhibit Akt phosphorylation, and both the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 and Akt knockdown resulted in Y705 dephosphorylation, indicating that Y705 dephosphorylation by sorafenib was mediated by inhibiting the PI3K/Akt pathway. Finally, in the rat HCC model, sorafenib signifi cantly inhibited STAT3 activity, reducing tumor growth and metastasis.CONCLUSION: Sorafenib inhibits growth and metastasis of HCC in part by blocking the MEK/ERK/STAT3 and PI3K/Akt/STAT3 signaling pathways, but independent of JAK2 and SHP2 activation.Fang-Ming Gu, Quan-Lin Li, Qiang Gao, Jia-Hao Jiang, Xiao-Yong Huang, Jin-Feng Pan, Jia Fan, Jian ZhouFang-Ming Gu, Quan-Lin Li, Qiang Gao, Jia-Hao Jiang, Xiao-Yong Huang, Jin-Feng Pan, Jia Fan, Jian Zhou, Liver Cancer Institute, Zhongshan Hospital and Shanghai Medical School, Fudan University, Shanghai 200032, China Author contributions: Gu FM, Li QL and Gao Q contributed equally to this work Gu FM and Li QL performed the experi- ments and interpretation of the data and statistical analysis Zhou J and Gao Q contributed to the conception and design of the study Gu FM, Gao Q, Li QL and Zhou J wrote the manuscript Jiang JH, Huang XY, Pan JF and Fan J made substantial contri- bution to the design and conception of the study and interpreta- tion of data all authors read and approved the f inal manuscript. 2011World Journal of Gastroenterology2011,17,34:18
9全场观测技术概念、进程与展望显示文摘简要综述理想的流体力学观测手段的概念,近代全场观测技术(包括激光空间流动显示,定量化流动显示,全场测量技术等)及其应用发展的踪迹和趋向.同时介绍作者在此领域的若干研究工作.Shen Gongxin (Beijing University of Aeronautics and Astronautics,Dept.of Flight Vehicle Design and Applied Mechanics) 1997北京航空航天大学学报1997,23,3:17
10Quasi-static Analysis of Thrust-loaded Angular Contact Ball Bearings Part Ⅰ:Theoretical Formulation显示文摘Ball bearings play an important role in various rotating machineries,but the complicated kinematic and tribological features of ball bearings make many aspects of their operating behaviors still inconclusive.Most theoretical analyses of ball bearings up to date are based on either the hypothesis of race control or other empirical models to determine the ball motion of ball bearings,but none of these strategies can reveal and consequently employ the intrinsic coupling mechanism between the spin and the tangential traction of contacting bodies rolling upon one another.To remedy the deficiency of current analytical models for ball bearing analysis,the rolling contact theory is employed to establish an explicit link between motions and interactions within ball bearings.A differential slip model is established to precisely define the slip component due to the significant curvature of the common contact patches between the ball and inner/outer raceways.The creepage and the spin ratio are formulated to accurately define the relative rigid motion between the ball and the inner/outer raceway.Then a quasi-static analytical model is established that can accurately determine the motions of the balls and races of the ball bearing.It can also give a vivid description of the slip and traction distributions within the contact area.The analytical model can be effectively used to analyze the operational conditions and tribological features of solid-lubricated ball bearings.It can also be used optimize the construction of ball bearings for specific applications.CHEN Wenhua1,2,MA Zikui1,GAO Liang1,LI Xinglin3,and PAN Jun2 1 Institute of Mechanical Design,Zhejiang University,Hangzhou 310027,China 2 Institute of Mechanical Design and Manufacturing,Zhejiang Sci-Tech University,Hangzhou 310018,China 3 State Testing Laboratory of Hangzhou Bearing Test & Research Center,Hangzhou 310022,China 2012Chinese Journal of Mechanical Engineering2012,25,1:16
11Wave Forces on Submerged Semi-Circular Breakwater and Similar Structures显示文摘—The results of design and experiment of a submerged semi-circular breakwater at the Yangtzeestuary show that the submerged structure will be unsafe when the general empirical wave force formulafor semi-circular breakwater is used in design.Therefore,a new calculation method for the wave forces act-ing on a submerged semi-circular structure is given in this paper,in which the wave force acting on the in-side circumference of semi-circular arch is included,and the phase modification coefficient in the generalempirical formula is adjusted as well.The new wave force calculation method has been verified by the re-sults of seven related physical model tests and adopted in the design of the south esturary jetty of the firststage project of Deep Channel Improvement Project of the Yangtze River Estuary,the total jetty length be-ing 17.5km.XIE Shileng Prof. Senior Engineer, The First Design Institute of Navigation Engineering, Ministry of Communications of China, Tianjin 300222, P. R. China. 1999China Ocean Engineering1999,14,1:15
12Tumor size as a prognostic factor in patients with advanced gastric cancer in the lower third of the stomach显示文摘AIM: To explore the impact of tumor size on outcomes in patients with advanced gastric cancer in the lower third of the stomach. METHODS: We retrospectively analyzed the clinical records of 430 patients with advanced gastric cancer in the lower third of the stomach who underwent distal subtotal gastrectomy and D2 lymphadenectomy in our hospital from January 1998 to June 2004. Receiver-operating characteristic (ROC) curve analysis was used to determine the appropriate cutoff value for tumor size, which was measured as maximum tumor diameter. Based on this cutoff value, patients were divided into two groups: those with large-sized tumors (LSTs) and those with small-sized tumors (SSTs). The correlations between other clinicopathologic factors and tumor size were investigated, and the 5-year overall survival (OS) rate was compared between the two groups. Potential prognostic factors were evaluated by univariate KaplanMeier survival analysis and multivariate Cox's propor-tional hazard model analysis. The 5-year OS rates in the two groups were compared according to pT stage and pN stage. RESULTS: The 5-year OS rate in the 430 patients with advanced gastric cancer in the lower third of the stomach was 53.7%. The mean ± SD tumor size was 4.9 ± 1.9 cm, and the median tumor size was 5.0 cm. ROC analysis indicated that the sensitivity and specificity results for the appropriate tumor size cutoff value of 4.8 cm were 80.0% and 68.2%, respectively (AUC=0.795, 95%CI: 0.751-0.839, P=0.000). Using this cutoff value, 222 patients (51.6%) had LSTs (tumor size ≥ 4.8 cm) and 208 (48.4%) had SSTs (tumor size<4.8 cm). Tumor size was significantly correlated with histological type (P=0.039), Borrmann type (P=0.000), depth of tumor invasion (P=0.000), lymph node metastasis (P=0.000), tumor-nodes metastasis stage (P=0.000), mean number of metastatic lymph nodes (P=0.000) and metastatic lymph node ratio (P=0.000). Patients with LSTs had a significantly lower 5-year OS rate than those with SSTs (37.1% vs 63.3%, P=0.000). Univariate analysis showed that depth of tumor invasion (c 2=69.581, P=0.000), lymph node metastasis (c 2=138.815, P=0.000), tumor size (c 2=78.184, P=0.000) and metastatic lymph node ratio (c 2=139.034, P=0.000) were significantly associated with 5-year OS rate. Multivariate analysis revealed that depth of tumor invasion (P=0.000), lymph node metastasis (P=0.019) and tumor size (P=0.000) were independent prognostic factors. Gastric cancers were divided into 12 subgroups: pT2N0; pT2N1; pT2N2; pT2N3; pT3N0; pT3N1; pT3N2; pT3N3; pT4aN0; pT4aN1; pT4aN2; and pT4aN3. In patients with pT2-3N3 stage tumors and patients with pT4a stage tumors, 5-year OS rates were significantly lower for LSTs than for SSTs (P<0.05 each), but there were no significant differences in the 5-year OS rates in LST and SST patients with pT23N0-2 stage tumors (P > 0.05). CONCLUSION: Using a tumor size cutoff value of 4.8cm, tumor size is a prognostic factor in patients with pN3 stage or pT4a stage advanced gastric cancer located in the lower third of the stomach.Hong-Mei Wang, Chang-Ming Huang, Chao-Hui Zheng, Ping Li, Jian-Wei Xie, Jia-Bin Wang, Jian-Xian Lin, Jun Lu, Department of Gastric Surgery, Affiliated Union Hospital of Fujian Medical University, Fuzhou 350001, Fujian Province, China Author contributions: Wang HM and Huang CM conceived of the study, analyzed the data, and drafted the manuscript Zheng CH, Li P and Xie JW helped revise the manuscript critically for important intellectual content Wang JB, Lin JX and Lu J helped collect data and design the study and all authors read and approved the final manuscript. 2012World Journal of Gastroenterology2012,18,38:15
13植物中有机硒含量的测定显示文摘对有机硒和无机硒的测定进行了探讨,利用压榨提取无机硒,用荧光二阶导数法进行硒的定量测定,通过标准添加法对提取率进行了测定,回收率为93.2%~98.4%,变异系数为1.86.Qin Fang(Centre Research and Design Institute,Wuxi University of Light Industry,Wuxi,214036) 1998无锡轻工大学学报(食品与生物技术)1998,17,4:15
14Alekseevskii-Tate revisited:An extension to the modified hydrodynamic theory of long rod penetration显示文摘The modified hydrodynamic theory of long rod penetration into semi-infinite targets was established independently by Alek-seevskii and Tate over forty years ago and since then many investigators contributed much to the development of the high speed penetration mechanics.However,in all the models proposed so far,the target resistance Rt is not well defined and usually determined by adjusting it until the predicted depth of penetration comes to an agreement with experimental data.In this paper,assumptions are first made about particle velocity and pressure profiles together with response regions in the target and then an extension is made to the modified hydrodynamic theory of long rod penetration into semi-infinite targets,in which Rt has explicit form and is dependent on penetration velocity as well as thermo-mechanical properties of target material.The present model is compared with long rod penetration tests for different material combinations.It transpires that the present model predictions are in good agreement with the experimental data and numerical simulations in terms of penetration depth although many assumptions and simplifications are introduced into the paper.LAN Bin & WEN HeMing CAS Key Laboratory for Mechanical Behavior and Design of Materials,University of Science and Technology of China,Hefei 230027,China 2010Science China(Technological Sciences)2010,53,5:14
15Power system low frequency oscillation monitoring and analysis based on multi-signal online identification显示文摘The advance in the wide-area measurement system (WAMS) is driving the power system to the trend of wide-area monitoring and control.The Prony method is usually used for low frequency oscillation online identification.However,the identified amplitude and phase information is not sufficiently used.In this paper,the amplitude is adopted to detect the occurrence of the oscillation and to obtain the mode observability of the sites.The phase is adopted to identify the oscillation generator grouping and to obtain the mode shapes.The time varying characteristics of low frequency oscillations are studied.The behaviors and the characters of low frequency oscillations are displayed by dynamic visual techniques.Demonstrations on the '11.9' low frequency oscillation of the Guizhou Power Grid substantiate the feasibility and the validation of the proposed methods.YUAN Ye1,2,SUN YuanZhang2,CHENG Lin2,CHEN Gang2 & WANG Peng3 1 State Nuclear Electric Power Planning Design and Research Institute,Beijing 100032,China 2 State Key Laboratory of Power Systems,Deptment of Electrical Engineering,Tsinghua University,Beijing 100084,China 3 EEE School,Nanyang Technological University,Singapore 2010Science China(Technological Sciences)2010,53,9:13
16Motion behavior of particles in air-solid magnetically stabilized fluidized beds for separation显示文摘In order to study the settling mechanism of particles in an air-solid magnetically stabilized fluidized bed(MSFB) for separation,we carried out free settling and quasi-zero settling tests on the tracing particles.The results show that the main resistance forces as the tracing particles settled in an air-solid MSFB were motion resistance force and yield force.The motion resistance and yield forces greatly hindered the free settling of the particles by greatly decreasing the acceleration for settling process of the particles.The acceleration decreased from 3022.62 cm/s 2 to zero in 0.1 s,and in the end,the particles stopped in the air-solid MSFB.The yield force on particles increased with increasing the magnetic field intensity,resulting in decrease of the quasi-zero settling displacement.However,the yield force on particles decreased with increasing the fluidized air velocity,leading to increase of the quasi-zero settling displacement.When the structure and operating parameters of the air-solid MSFB were set up,the yield stress on particles stopped in an air-solid MSFB was a function of diameter and density of particles.The settling displacements of equal diameter particles increased with increasing their densities,and the settling displacements of equal density particles increased with increasing their diameters.Song Shulei a,,Zhao Yuemin a,Luo Zhenfu a,Tang Ligang b a School of Chemical Engineering and Technology,China University of Mining & Technology,Xuzhou 221116,China b Coal Mining and Designing Department,Tiandi Science & Technology Company Co.Ltd.,Beijing 100013,China 2012International Journal of Mining Science and Technology2012,22,5:13
17Effects of Astragaloside Ⅳ Derivative on Heart Failure in Rats显示文摘Objective Astragaloside Ⅳ derivative(ASId) is one of Astragaloside Ⅳ(ASI) derivatives with higher water-solubility and may have more druggability than ASI.The present study aims at observing the effects of ASId on cardiovascular parameters in chronic heart failure in rats.Methods Using echocardiographic and haemodynamic measurements,the effects of ASId on congestive heart failure(CHF) induced by ligation of the left coronary artery in rats were investigated.Results ASId iv 0.5,1.0,and 2.0 mg/(kg·d) attenuated the decline of ejection fraction.The peak derivatives of the left ventricle(LV) pressure(dp/dt) in ASId treated groups were significantly increased.Both LV volumes in diastole and in systole were decreased significantly after ASId treatment,accompanied with a trend towards normalization of relative wall thickness at end-systole.ASId 0.5,1.0,and 2.0 mg/(kg·d) attenuated the increase of LV systolic and diastolic wall stress.ASId treatment also inhibited compensatory hypertrophy of depressed heart.Conclusion ASId could improve cardiac functions and inhibite compensatory hypertrophy and LV remodelling,which suggests the possibility of ASId as a new therapeutic drug for the treatment of CHF.WANG Wei-ting1,ZHAO Zhuan-you1,HAN Ying-mei2,XU Wei-ren2,TANG Li-da1 1.State Key Laboratory of Pharmacokinetics and Pharmacodynamics,Tianjin Institute of Pharmaceutical Research,Tianjin 300193,China 2.Tianjin Key Laboratory of Molecular Design & Drug Discovery,Tianjin Institute of Pharmaceutical Research,Tianjin 300193,China 2010Chinese Herbal Medicines2010,2,1:13
18KINETICS OF REACTION BETWEEN PbS AND PbO显示文摘The rate equation of reaction between PbS and PbO is dα/dt=kxPbS3 xPbO-2.A transition product,PbSO4·2PbO,is found by X-ray diffraction analysis.The reaction mechanism was dis-cussed on the basis of electron transfer.LI Cheng Beijing Central Design and Research Institute for Non-Ferrous Metallurgical Industry,Beijing,ChinaLIU Chunpeng,Kunming Institute of Technology,Kunming,China LI Cheng,Metallurgical Dept.No.l,Beijing Central Design and Research Institute for Non-Ferrous Metallurgical Industry,Beijing 100038,China 1990Acta Metallurgica Sinica(English Letters)1990,3,11:12
19Preparation and characterization of nitrogen-doped titanium dioxides显示文摘A type of high visible-light active titanium oxinitride(TiO2-xNx) powder was prepared by a simple proc-ess:the calcination of the hydrated titanium dioxide at the atmosphere of ammonia-argon using a tu-bular electric furnace at high temperatures. The hydrated titanium dioxide was synthesized as the precursor of TiO2-xNx using titanic acid as raw material,which came from sulfate technique of produc-ing titanium white. The effects of temperature and reaction time on the nitrogen content,grain size and crystal structure were studied. The visible-light activity and photocatalysis capability of the powder were also investigated.ZHU GuoPing1 & ZHOU KangGen2 1 Environmental Science Research & Design Institute of Zhejiang Province,Hangzhou 310007,China 2 Department of Environmental Engineering,School of Metallurgical Science and Engineering,Central South University,Changsha 410083,China 2007Science China Chemistry2007,50,2:10
20Velocity and pressure distributions in discharge tunnel of rotary-obstruction composite inner energy dissipation显示文摘On the basis of model test and theoretical analysis of velocity and pressure distributions,an hypothesis is presented that the distribution of tangential velocity in radial direction seems to be a combinational distribution of a quasi-free vortex and a quasi-forced vortex for the discharge tunnel of rotary-obstruction composite inner energy dissipation.The variations of corresponding parameters about the hypothesis are obtained under test conditions in this paper.The formula of pressure distribution in radial direction is deduced theoretically,and the theoretical values of pressure distribution computed by the formula are well consistent with the measured ones,showing that the formula is correct and can be applied to the computation and analysis of pressure distribution of this discharge tunnel.CAO ShuangLi 1,NIU ZhengMing 1,YANG Jian 2 & LU HongBo 1 1 Xi’an University of Technology,Xi’an 710048,China 2 China Water Resources Pearl River Planning,Surveying & Designing Co.Ltd,Guangzhou 510610,China 2011Science China(Technological Sciences)2011,54,S1:10
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