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Mechanisms of reactive element Y on the purification of K4169 superalloy during vacuum induction melting

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International Journal of Minerals,Metallurgy and Materials 2018年第6期25卷 696-703页

作者： qing-ling li Hua-rui Zhang Ming Gao Jin-peng li Tong-xiao Tao Hu Zhang School of Materials Science and Engineering Beihang University Beijing 100191 China qingdao Institute of New Material Technology of Beihang University Qingdao 266000 China

The effects of rare earth element Y on the purification of K4169 superalloy during vacuum induction melting were investigated at different superheating temperatures. The corresponding interaction mechanisms were also clarified. Results showed that the addition of Y remarkably promoted the purification effect on the K4169 melt. The contents of O and S in the K4169 as-cast alloy ingots after purification were 3–4 and 8–10 ppm, respectively. The degrees of deoxidation and desulfurization increased to 50% and 57%, respectively, upon the addition of 0.1 wt% Y. The yttrium-rich phase that precipitated at the grain boundary blocked the diffusion of C and the accumulation of S, thereby contributing to the purification of the alloy.

关键词： K4169 superalloy deoxidation desulfurization yttrium vacuum induction melting mechaNsm

Electrokinetic pumping system based on nanochannel membrane for liquid delivery

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Chinese Chemical Letters 2007年第3期18卷 352-354页

作者： ling Xin Chen qing ling li Xiao Lei Wang Hai Long Wang Ya Feng Guan College of Chemistry Chemical Engineering and Materials Science Shandong Normal University Jinan 250014 China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

Nonmechanical pumping of liquids is of key importance for applications from the biomedical microfluidic chip to drug delivery systems. In this paper, a new electrokinetic pump （EOP） system with polycarbonate nanoehannel membrane sandwiched between two membrane holders was constructed. The pump was tested with water and phosphate buffer at 1-6 V applied voltage, the maximum pressure and flow rate are 0.32 MPa （3.2 atm） and 4.2 μL/min for phosphate buffer, respectively. This proof-of-concept pump shows its potential use for drugs or chemical agents delivery by the usage of different membrane materials.

关键词： Electrokinetic pump Electroosmotic pump Nanochannel Microfluidic chip μTAS

Does the Hartman effect exist in triangular barriers

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Chinese Physics B 2024年第3期33卷 214-230页

作者：李青玲郑爽肖智 Department of Mathematics and Physics North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000Chin

We study the phase,Larmor and dwell times of a particle scattered off triangular barriers(TBs).It is interesting that the dependences of dwell,reflective phase and Larmor times on the wave number,barrier width and height for a pair of mirror-symmetric(MS)exact triangular barriers(ETBs)are quite different,as the two ETBs have quite distinct scattering *** comparison,the dependence of the transmitted phase or Larmor times is exactly the same,since the transmitted amplitudes are the same for a pair of MS *** further study the Hartman effect by defining the phase and Larmor velocities associated with the phase and Larmor *** find no barrier width saturation effect for the transmitted and reflected *** is indicated by the fact that all the velocities approach finite constants that are much smaller than the speed of light in vacuum for TBs with positive-slope impact *** for ETBs with vertical left edges,the naive velocities seem to also indicate the absence of the Hartman *** are quite distinct from rectangular barriers and may shed new light on the clarification of the tunneling time issues.

关键词： triangular barrier Hartman effect

Composition and bioactivity of secretion from Stauronematus compressicornis (Fabricius)

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Forestry Studies in China 2009年第2期11卷 122-126页

作者： ZHAO Xiao-dan MENG qing-ling YU li-zheng li Meng-lou Forestry Entomology Laboratory of Academic Forestry Northwest A＆F University Yangling 712100 P. R. China

We analyzed the composition and studied the bioactivity of secretion from the poplar sawfly, Stauronematus compressicornis （Fabricius）. A leaf-sandwich method was applied to test the bioactivity of the secretion. Coomassie brilliant blue, gas chromatography （GC） and other methods were used to analyze and carry out protein assays, amino acid analyses, fatty acid and cholesterol detection of the secretion. Results show that the secretion had a significant antifeeding effect on 4th instar larvae of the armyworm （Pseudaletia separata Walker）. Dissolved in 0.27 mol.L^-1 HCl, 0.1 mol.L^-1 NaOH and 0.05 mol.L^-1 Na2HPO4 separately, the secretions had antifeeding rates ranging from 22.7% to 49.6%. Meanwhile, the weights of the secretion-treated insects were significantly lower than those of the control. Biochemical detection showed that the proteins contained in the secretion were composed of 16 amino acids. The secretion also contained small amounts of cholesterol and fatty acids, which included lauric acid, myristic acid, myristoleic acid, seventeen carbonic acids and oleic acid.

关键词： Stauronematus compressicornis (Fabricius) secretion composition bioactivity antifeeding rate

Quantification of liver fat deposition in obese and diabetic patients:A pilot study on the correlation with myocardium and periapical fat content

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liver Research 2022年第2期6卷 103-110页

作者： Xi Chen Hui-Quan Wen qing-ling li li-Shan Shen Xiao-Wen Luo Bin Zhou Ruo-Mi Guo Department of Radiology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina Department of VIP Medical Center The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina Department of Cardiology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina

Backgroud and aim:Non-alcoholic fatty liver disease(NAFLD)is a worldwide health problem,which associated with systemic health problems and causes a higher risk of all-cause *** leading causes of death in NAFLD patients are cardiac complications followed by NAFLD-related liver *** study aimed to quantitatively measure the contents of liver and cardiac fat with varying degrees of NAFLD in an obese group and a type 2 diabetes mellitus(T2DM)group to explore differences and *** and methods:This study included 170 patients who underwent echo asymmetry and least square estimation-iron quantification sequencing at 3.0 T magnetic resonance *** fraction values were quantitatively measured in regions of interest of the liver,myocardium,and periapical adipose ***:In both the obese and T2DM groups,cardiac fat content was correlated with liver fat content using linear regression(Pliver severity by multiple comparisons of different degrees of NAFLD(Pliver(obese group,Pliver had higher myocardial fat content than obese patients with fatty liver,and both had a linear *** fat is an index for liver fat deposition in *** myocardial fat contents in T2DM patients with an increase in the liver fat content,which would influence cardiac function,should be given more attention in clinic.

关键词： Cardiac fat content Diabetes mellitus Obesity Non-alcoholic fatty liver disease(NAFLD) Type 2 diabetes mellitus(T2DM) Magnetic resonance imaging(MRI)

Endoscopic Mucosal Resection of Mucosal Neoplasm Located on the Duodenal Bulb through Endoscope Retroflexion

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Clinical oncology and cancer researeh 2010年第5期7卷 289-293页

作者： Hua li Qiang li Jian-zhang HU Guo-qing ZHANG Feng-ling li Department of Endoscopy 2 Department ofHepatobiliary Surgery Tianjin Medical University Cancer institute & Hospital Tianjin 300060China.

OBJECTIVE To assess the results of endoscopic mucosal resection （EMR） of benign mucosal neoplasms located on the duodenal bulb using endoscope retroflexion. METHODS This study involved 14 patients with 16 mucosal neoplasms located on the duodenal bulb. The diameter of each neoplasm was less than 15 mm. After endoscope retroflexion within the duodenum for evaluation of the size, extent and depth of the tumor, EMR was attempted with endoscope retroflexion for removing the lesion in the duodenal bulb. The rate of endoscope retroflexion, the time required for endoscope retroflexion, median operation time, curative resection rate, en bloc resection rate, complication, and median follow-up period were evaluated. RESULTS Sixteen lesions in 14 patents （median age of 56 years, 5 female, 9 male） were removed through EMR. The mean size of the lesions resected was 6.9 mm （median size of 5.5 mm, range of 3-15 mm）. Post-EMR histologic examination revealed Brunner＇s gland hyperplasia in 6, gastric mucosal metaplasia in 5, adenoma in 1, chronic inflammation in 3, and benign lymphocytic hyperplasia in 1. The curative resection rate was 100% （16/16）, and the en bloc resection rate was 94% （15/16）, with EMR. One of the lesions was piecemeal removed through EMR for its large size （15 mm） and for its involving the area from the duodenal bulb to the pyloric ring. The success rate of endoscope retroflexion within the duodenum was 94% （15/16）. The time required for endoscope retroflexion was longer for the first 10 lesions （median time of 2 min, range of 1-2.5 min） than that for the last 5 lesions （median time of 1.5 min, range of 1-2 min）. The median follow-up period was 22 months （range of 4-48 months）. During the follow-up, no residual, no pyloric or duodenal stenosis was found in any of the patients after EMR. There was no severe hemorrhage, or perforations occurring. CONCLUSION EMR of mucosal neoplasm located on the duodenal bulb through endoscope retroflexion, which is a feasible and

关键词： endoscopic mucosal resection mucosal neoplasm duodenal bulb endoscope retroflexion.

Three-Dimensional Concurrent Design System for Walking-Beam Furnace

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Computer Aided Drafting,Design and Manufacturing 2010年第1期20卷 1-8页

作者： ZHAO Yao YU qing-bo li ling-xin School of Materials ＆ Metallurgy Northeastern University Shenyang 110819 China

This paper focuses on the problem of low efficiency and limited non-geometric information handling ability in the process of 2D heating furnace design, proposes a 3D concurrent parametric design system, this method is realized by parametric design technology, which is supported by ActiveX-Automation technology and VBA technology, mutual visit between application programs makes batched modeling become possible, key dimensions are linked with each other by restrictions, so parts can be built concurrently by sharing few parameters between common borders, designer can be free from repeated drawing work during modification, Solid Edge is chosen as the modeling server, a secondary development software is programmed by Visual Basic, this system provides a feasible way to overlap time between different sections, the design efficiency and quality is improved significantly.

关键词： heating furnace 3D secondary development Solid Edge parametric design

Longitudinal observation of an interferon gamma-released assay （***） for Mycobacterium tuberculosis infection in AIDS patients on highly active antiretroviral therapy

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Chinese Medical Journal 2010年第9期123卷 1117-1121页

作者： ZHANG li-fan liU Xiao-qing ZUO ling-yan li Tai-sheng DENG Guo-hua WANG Ai-xia Department of Infectious Diseases Peking Union Medical College HospitalChinese Academy of Medical Sciences & Peking Union Medical CollegeBeijing 100730China

Background *** is a novel test for tuberculosis infection with higher sensitivity and specificity than the traditional tuberculin skin test （TST）. However, there are no longitudinal data in the literature evaluating *** for Mycobacterium tuberculosis in patients with acquired immune deficiency syndrome （AIDS） on highly active antiretroviral therapy （HAART）. The objective of this study was to assess the value of *** longitudinally in AIDS patients on HAART without prophylaxis for *** A prospective observational study was conducted in 50 AIDS patients on HAART. None of the subjects had evidence of active tuberculosis. ***, a T-cell-based interferon y released assay, was performed at the onset of the study and repeated 24 months thereafter. Subjects were evaluated every 6 months during the 36-month follow-up. Results Twenty-one （42%） AIDS patients on HAART tested positive by *** （95% Cl 28.3%-55.7%）. The pooled spot-forming cells of early secretory antigenic target-6 （ESAT-6） and culture filtrate protein-10 （CFP-10） peptides were 68/million peripheral blood mononuclear cell （PBMC）（interquartile range 44-220）. The average number of CD4 cells in subjects was （305±152） cells/Ml and there was no significant difference in *** response rates between subjects with CD4 cell counts 〈200 cells/ul （7/15 （46.7%）, 95% C/21.5%-71.9%） and those with CD4 cell counts≥200 cells/ul （14/35 （40.0%）, 95% Cl 23.8%-56.2%, P=0.662）. In the 32 subjects who completed the 24-month follow-up, 10 underwent *** reversion, one had *** conversion, six remained positive and 15 remained negative. None of them advanced to active tuberculosis during the 36-month *** The inactive status of tuberculosis infection may be maintained for a long period in AIDS patients on HAART.

关键词： T-SPOT.TB Mycobacterium tuberculosis AIDS highly active antiretmviral therapy longitudinal assessment

基于改进K-S检测的STBC-OFDM信号盲识别算法研究

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通信学报 2017年第4期38卷 46-54页

作者：凌青张立民闫文君海军航空工程学院信息融合所山东烟台264001

针对多输入单输出(MISO,multiple input single output)通信系统的STBC-OFDM信号盲识别问题,提出基于OFDM块的改进Kolmogorov-Smirnov(K-S)检测方法。该方法首先对MISO通信系统的STBC-OFDM信号建模;然后利用STBC-OFDM信号编码矩阵的相关性,构造不同时延向量下STBC-OFDM接收信号OFDM块的经验函数作为特征函数;最后通过改进K-S检测方法检验经验分布函数之间的距离盲识别STBC-OFDM信号。该方法不需要噪声信息、调制信息和信道系数,适合非合作通信场合。理论分析和实验验证了该方法的可行性。

关键词： MISO通信系统 STBC-OFDM信号改进K-S检测经验分布函数