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Numerical simulation of airfoil flows with a turbulence model

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航空动力学报 2014年第2期29卷 475-480页

作者： GAO lin jiang li-jun CUI Shu-xin GAO Ge National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power EngineeringBeijing University of Aeronautics and Astronautics

Turbulent flows over AS240and NACA4412airfoil were simulated numerically using a two-equation turbulence model named k-ξ*** predictions of velocity profiles and the pressure coefficient of airfoil AS240at 8°/19°attack angle and NACA4412at 13.87°attack angle were *** results were compared with those using k-εand k-ω models,as well as experimental *** indicates that the newk-ξmodel offers more realistic prediction than the other two *** main finding shows that the newk-ξmodel is good at predicting separated flows around airfoils,and it captures the flow feature of pressure-induced separation *** calculations are implemented as per openFOAM 1.7.1(open source field operation and manipulation).

关键词： turbulence airfoil incompressible separation openFOAM

Multistage soft decision equalization technique for MIMO systems in frequency selective channels

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 7-11页

作者： YU jiang li Xiao-jun YUE Guang-xin Digital Communications and Networking Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes a multistage soft decision equalization （SDE） technique for block transmission over frequency selective multi-input multi-output （MIMO） channels. Using the Toeplitz structure, the general signal model can be converted into a series of small-sized sub-signal models. For each sub-signal model, soft interference cancellation （SIC） is used firstly to remove partial effects of interfering symbols, then max-log-map sphere decoder is performed to get the desired a posteriori information. Simulation shows that with lower complexity the proposed method outperforms the probability data association SDE and the Schnorr-Euchner sphere decoder.

关键词： sphere decoder SDE

Clinical significance of combined determination of serum PGⅠ , PGⅡ and GAS for diagnosis of gastric cancer

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Nuclear Science and Techniques 2005年第4期16卷 217-220页

作者： jiang Meng-jun li Wen-Xin XIAO Zhi-Jian ZHANG Rong-jun CAI Gang-Ming State Key Laboratory of Nuclear Medicine Jiangsu Institute of Nuclear Medicine. Wuxi 214063

To evaluate the clinical value of combined determination of serum PGⅠ, PGⅡ and GAS for early diag-nosis of gastric cancer, the serum levels of PGⅠ, PGⅡ and GAS in 190 healthy controls and 129 patients with gas-tric disorders were measured by RIA. The 129 patients include 68 cases of gastric cancer. The results showed that the serum levels of PGⅠ and PGⅠ/PGⅡ ratio in gastric cancer patients were obviously lower than those in healthy controls, while comparing with controls, the serum GAS levels were significantly higher. The diagnostic accuracy of the determinations for gastric cancer was evaluated by receiver operating characteristic (ROC) curve analysis. The area under the curve (AUC) levels of serum PGⅠ, PGⅠ/PGⅡ ratio and GAS were 0.833, 0.842 and 0.851, respec-tively. As serum PGⅠ or PGⅠ/PGⅡ ratio or GAS were combined, the sensitivity and specificity of determination for gastric cancer diagnosis were 94.2% and 73.4%, respectively. All these results indicated that the combined deter-mination of serum PGⅠ, PGⅡ and GAS levels may be used as a tool for primary screening of gastric cancer.

关键词：免疫血清诊断方法胃癌放射性疗法实验室诊断放射性同位素

Columnar to Equiaxed Transition During Solidification of Small Ingot by Using Electric Current Pulse

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Journal of Iron and Steel Research International 2009年第6期16卷 7-12页

作者： li Jie MA Jian-hong SONG Chang-jiang li Zhi-jun GAO Yu-lai ZHAI Qi-jie Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University Shanghai 200072 China

A new approach to applying the electric current pulse （ECP） with parallel electrodes to the promotion of the transition from columnar crystal to equiaxed crystal and the improvement of macrosegregation was introduced. The ECP was applied to different stages of the solidification. The results showed that the application of the ECP in both the initial stage （the thickness of solidified shell reached 2 mm approximately） and the late stage （the thickness of solidified shell reached 14 mm approximately） of solidification can promote the columnar to equiaxed transition （CET）. The analysis showed that during solidification, a large number of nuclei around the upper surface fell off due to ECP, which subsequently showered on the melt and impinged the growth front of the columnar crystal. Therefore, the CEToccurred. In addition, this method was also employed to influence the solidification process of bearing steel, and the results showed that the structure was changed from columnar crystal to equiaxed crystal, indicating that ECP can enhance the homogeneity of structure and composition of bearing steel.

关键词： columnar to equiaxed transition solidification electric current pulse macrosegregation

Interactions of Heavy Metal Ions with Paddy Soils as Inferred from Wien Effect Measurements in Dilute Suspensions

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Pedosphere 2006年第6期16卷 718-725页

作者： jiang jun li Cheng-Bao ZHAO An-Zhen XU Ren-Kou WANG Yu-jun S. P. FRIEDMAN Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Institute of Soil Water and Environmental Sciences Agricultural Research Organization Voleani Center Bet Dagan 50250 Israel

Interactions of three heavy metal ions, Cu^2＋, Cd^2＋, and Pb^2＋, and, for comparison, Na^＋ with electrodialytic clay fractions （less than 2μm in diameter） of four paddy soils as well as a yellow-brown soil as a control soil were evaluated based on measurements of the Wien effect in dilute suspensions with a clay concentration of 10 g kg^-1 in four nitrate solutions of 2 × 10^-4/z mol L^-1, where z is the cation valence, and a nitric acid solution of 3 × 10^-5 mol L^-1, Field strengths ranging from 15 to 230 kV cm^-1 were applied for measuring the electrical conductivities （ECs） of the suspensions. The mean free binding energies between the various cations and all of the soils determined from exchange equilibrium increased in the order： Na^＋〈 Cd^2＋〈 Cu^2＋〈 Pb^2＋. In general, the ECs of the suspensions in the sodium nitrate solution were smaller than those of the suspensions in the heavy metal solutions because of the lower electrophoretic mobility of sodium compared to the divalent cations. In terms of relative electrical conductivity-field strength relationships, relative electrical conductivity （REC） of suspensions containing various cations at field strengths larger than about 50 kV cm^-1 were in the descending order： Na^＋〉 Cu^2＋〉 Cd^2＋〉 Pb^2＋ for all tested soils. A characteristic parameter of the REC-field strength curves, AREC200, REC at a field strength of 200 kV cm^-1 minus that at the local minimum of the concave segment of the REC-field strength curves, characterized the strength of adsorption of the cations stripped off by the applied strong electrical field, and for all soils the values of AREC200 were generally in the order： Na^＋〈 Cu^2＋ ≤ Cd^2＋〈 Pb^2＋.

关键词： binding energy electrical conductivity field strength heavy metal ions paddy soils

LC-MS determination and pharmacokinetic study of salidroside in rat plasma after oral administration of suspensions of traditional Chinese medicine Erzhi Wan and Fructus ligustri lucidi

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Journal of Pharmaceutical Analysis 2011年第1期1卷 8-12页

作者： Ze-Yun li Qing li jiang Lu jun-Hong ling Xi-Hua Yu Xiao-Hui Chen Kai-Shun Bi School of Pharmacy Shenyang Pharmaceutical University Shenyang 110016 China.

A simple,rapid and sensitive liquid chromatography-mass spectrometry（LC-MS）method was developed for the determination of salidroside in rat plasma and study of its pharmacokinetics after oral administration of suspension of Erzhi Wan and Fructus ligustri lucidi into Wistar *** sample of 200 μL was extracted with acetic ether-isopropanol（2∶1）and the extraction was performed on a Kromasil C18 column（150 mm×4.6 mm,5 μm）with the mobile phase of methanol-water（41∶59,v/v）within a run time of 6.0 *** analyte was monitored with positive electrospray ionization（ESI）by selected ion monitoring（SIM）*** target ions were m/z 323.05 for salidroside and m/z 411.05 for internal standard（IS）geniposide.A good linear relationship was obtained over the range of 5.0-500.0 ng/mL and the lower limit of quantification was 5.0 ng/*** validated method was successfully applied to the pharmacokinetic study of salidroside in rat plasma after oral administration of suspension of Erzhi Wan and Fructus ligustri lucidi.

关键词： liquid chromatography-mass spectrometry(LC-MS) pharmacokinetics salidroside Erzhi Wan Fructus ligustri lucidi

Effect of Transcatheter Embolization by Autologous Fat Particles in the Treatment of Coronary Artery Perforation During Percutaneous Coronary Intervention

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Chinese Medical Journal 2015年第6期128卷 745-749页

作者： li-Yun He jiang-li Han li-jun Guo Fu-Chun Zhang Ming Cui Wei Gao Department of Cardiology Peking University Third Hospital Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides Ministry of Health Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing 100191 China

Background:Coronary artery perforation (CAP) is a rare but severe complication of percutaneous coronary intervention (PCI).The aim of our study was to evaluate the effect and safety of transcatheter embolization by autologous fat particles in the treatment of ***:Once the CAP was confirmed,a little autologous subcutaneous fatty tissue was obtained from the groin of the patient and then was made into 1 mm× 1 mm fat *** perforated vessel was embolized by fat particles via a *** were eight patients undergoing transcatheter embolization by autologous fat particles in the treatment of CAP during PCI in Peking University Third Hospital from February 2009 to june 2014,and the clinical data of these patients were collected and analyzed ***:The lesion morphology of the patients was classified based on the American College of Cardiology/American Heart Association Task Force classification,there were one patient with Class B2 lesion and seven patients with Class C lesions (there were five patients with chronic total occlusion lesions).According to the Ellis classification of CAP,there were six patients with Class Ⅱ perforations and two patients with Class Ⅲ *** causes of perforation included that seven patients induced by guide wire and one patient by balloon *** patients had pericardial *** of the eight patients with CAP underwent transcatheter embolization by autologous fat *** angiography confirmed that all of them were embolized *** was no severe complication after the *** coronary angiography of one patient at l week and another patient at 2 years after the embolization showed that the embolized arteries had *** median follow-up time was 20.3 months (8.8-50.2 months),the event-free survival rate was 100％.Conclusions:Transcatheter embolization by autologous fat particles was an effective,safe,cheap,and easy way to treat the perforat

关键词： Autologous Fat Particles Coronary Artery Perforation Embolization Percutaneous Coronary Intervention

Oral vaccination of mice against rodent malaria with recombinant Lactococcus lactis expressing MSP-1_(19)

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World Journal of Gastroenterology 2005年第44期11卷 6975-6980页

作者： Zhi-Hong Zhang Pei-Hong jiang Ning-jun li Mi Shi Weida Huang Department of Biochemistry School of Life Science Fudan University Shanghai 200433 China

AIM： To construct the recombinant Lactococcus/actis as oral delivery vaccination against malaria. METHODS： The C-terminal 19-ku fragments of MSP1 （MSP-119） of Plasmodium yoelii265-BY was expressed in L. lactis and the recombinant L. lact/s was administered orally to BALB/c and C57BL/6 mice. After seven interval vaccinations within 4 wk, the mice were challenged with P. yoelii 265-BY parasites of erythroo/tic stage. The protective efficacy of recombinant L. lactiswas evaluated. RESULTS： The peak parasitemias in average for the experiment groups of BALB/c and C57BL/6 mice were 0.8± 0.4% and 20.8±26.5%, respectively, and those of their control groups were 12.0±0.8% and 60.8±9.6%, respectively. None of the BALB/c mice in both experimental group and control group died during the experiment. However, all the C57BL/6 mice in the control group died within 23 d and all the vaccinated mice survived well. CONCLUSION： The results imply the potential of recombinant L. lactis as oral delivery vaccination against malaria.

关键词： Lactococcus lactis Oral delivery vaccination Malaria

Mitigated calcification of glutaraldehyde-fixed bovine pericardium by tannic acid in rats

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Chinese Medical Journal 2008年第17期121卷 1675-1679页

作者： WANG De jiang Hong li jun ZHOU Jian-ye HU Sheng-shou Research Center for Cardiovascular Regenerative Medicine Ministry of Health Cardiovascular Institute and Fuwai Hospital Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100037 China

Background Bioprosthetic heart valves derived from glutaraldehyde （Glut）-fixed xenografts have been widely used to replace diseased cardiac valves. However, calcification and degeneration are common following their implantation. Inflammation is closely associated with calcification of Glut-fixed xenografts via macrophage infiltration. Tannic acid （TA） possesses anti-inflammatory effects. This study was designed to investigate the anti-calcification of TA treatment on the Glut-fixed bovine pericardium （BP） in a rat subdermal model. Methods Fresh BP was divided into two groups （10 in each group） and separately subjected to different fixation procedures as follows：（1） Glut group： fixation with 0.6% Glut alone; （2） Glut/TA group： fixation with 0.6% Glut and subsequent 0.3% TA. Then the BP samples were subdermally implanted in juvenile male Sprague-Dawley rats and explanted 21 days after implantation. Each explanted BP sample was divided into three parts for calcium content analysis von Kossa＇s staining and immunohistochemical staining, and reverse transcription-polymerase chain reaction study. Results The data from quantitative calcium analysis and von Kossa＇s staining showed that Glut-fixed BP developed significantly more calcification than Glut/TA-fixed BP （（90.3＋32.5） mg/g dry weight vs （6.4_＋1.3） mg/g dry tissue, P 〈0.01）. Immunostaining demonstrated lower matrix metalloproteinase-9 and tenascin-C expression as well as macrophage infiltration into Glut/TA-fixed BP than in its Glut-fixed counterpart （P 〈0.01 for all）. Additionally, the reverse transcription-polymerase chain reaction study showed that higher levels of expression of matrix metalloproteinase-9 and tenascin-C mRNA occurred within Glut-fixed BP than within the Glut/TA-fixed ones （P 〈0.01 for all）. Conclusion TA exerts excellent anti-calcification effects on Glut-fixed BP via inhibiting macrophage infiltration and expression of matrix metalloproteinase-9 and tenascin-C.

关键词： tannic acid calcification macrophage pericardium bioprosthesis xenograft