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Communications in Theoretical Physics 2008年第6期49卷 1561-1566页

作者： guo Yong-feng xu Wei LI Dong-Xi XIE Wen-Xian Department of Applied Mathematics Northwestern Polytechnical University Xi＇an 710072 China

A stochastic dissipative dynamical system driven by non-Gaussian noise is investigated. A general approximate Fokker-Planck equation of the system is derived through a path-integral approach. Based on the definition of Shannon＇s information entropy, the exact time dependence of entropy flux and entropy production of the system is calculated both in the absence and in the presence of non-equilibrium constraint. The present calculation can be used to interpret the interplay of the dissipative constant and non-Gaussian noise on the entropy flux and entropy production.

关键词： information entropy entropy flux and entropy production non-Gaussian noise Fokker-Planck equation

The value of endoscopic ultrasonography on diagnosis and treatment of esophageal hamartoma

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第8期9卷 662-666页

作者： guo-qiang xu feng-ling HU Li-hua CHEN guo-dong SHAN Bing-ling ZHANG Department of Gastroenterology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective:To examine the values of endoscopic ultrasonography (EUS) on diagnosis and treatment of esophageal hamartoma. Methods:We compared and analyzed various kinds of imaging examinations such as barium esophagram, con-trast-enhanced computed tomography (CT) and conventional gastroscopy in retrospectively reviewing the clinical data of an esophageal hamartoma patient seen in our clinic in the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China. Having received various imaging examinations, this patient was finally diagnosed with esophageal hamartoma and underwent gastroscopic resection of hamartoma with the diagnostic information obtained from EUS. The patient had been regularly followed up for 13 months after treatment. Results: Barium esophagram, CT and conventional gastroscopy detected the lesion, but were unable to distinguish it from common esophagopolypus and other submucosal lesions, and unable to determine etiopathogenisis. EUS detected the hamartoma and identified its internal structure, echo, exact size, depth of invasion, origin and the relationship between adjacent tissues and organs, differentiating the lesion from other submucosal tumors and clearly defining the diagnosis. EUS-guided fine needle aspiration (FNA) also helped to identify the etiological diagnosis. Conclusion: EUS was superior to other imaging means in diagnosis and treatment of hamartoma.

关键词： Esophageal hamartoma Endoscopic ultrasonography (EUS) Gastroscopic resection

Shape Setup System for 1700 Hot Strip Mill

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Journal of Iron and Steel Research International 2007年第5期14卷 27-30页

作者： guo Zhong-feng xu Jian-zhong LI Chang-sheng LIU Xiang-hua State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Shape setup （SSU） system is the core technology for hot strip mill （HSM）. A precise SSU system was used to improve the strip quality for HSM. The function of SSU, setup, and feedback was introduced. The main mathematical models of roll gap profile and longitudinal strain difference are set up. Strip profile allocation strategy was researched according to the SSU system of a domestic 1 700 mm HSM. The SSU system was put into practical use and the measurement results showed that strip flatness variation and strip profile variation could be controlled in target scope.

关键词： SSU hot strip mill, shape strip profile flatness

Novel Brфnsted Acidic Ionic Liquid Based on a Cyclic Guanidinium Cation:a Green,Efficient,and Recyclable Dual Slovent-catalyst System for Fisher Esterification

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Chemical Research in Chinese Universities 2007年第6期23卷 665-668页

作者： guo xu DUAN Hai-feng SUN Hai CAO Jun-gang LIN Ying-jie Department of Organic Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

A novel BrФnsted acidic ionic liquid（IL） based on the cyclic guanidinium cation has been synthesized. This IL, as a strong BrФnsted acid catalyst or solvent, shows high catalytic activity and biphsaic behavor in the esterifications of carboxylic acids and alcohols. The produced esters as a separate phase can be conveniently decanted out from the IL and the IL is recyclable without any loss of catalytic activity.

关键词： BrФnsted acid Ionic liquid Guanidinium Fisher esterification

Instability in Two-Sided Thermocapillary-Buoyancy Convection with Interfacial

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Chinese Physics Letters 2020年第1期37卷 19-23页

作者： guo-feng xu Qiu-Sheng Liu Jun Qin Zhi-Qiang Zhu Institute of Mechanics Chinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

A new model of two-phase thermocapillary-buoyancy convection with phase change at gas-liquid interface in an enclosed cavity subjected to a horizontal temperature gradient is proposed,rather than the previous onesided model without phase *** study the onset of multicellular convection and two inodes of convective instability,and find four different flow *** transition map is compared with the non-phase-change *** numerical results show the stabilizing effect of interfacial phase change on the thermocapillarybuoyancy convection.

关键词： capillary thermocapillary phase

Prediction of oxygen concentration and temperature distribution in loose coal based on BP neural network

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Mining Science and Technology 2009年第2期19卷 216-219页

作者： ZHANG Yong-jian WU guo-guang xu Hong-feng MENG Xian-liang WANG Guang-you School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

An effective method for preventing spontaneous combustion of coal stockpiles on the ground is to control the air-flow in loose coal. In order to determine and predict accurately oxygen concentrations and temperatures within coal stockpiles, it is vital to obtain information of self-heating conditions and tendencies of spontaneous coal combustion. For laboratory conditions, we designed our own experimental equipment composed of a control-heating system, a coal column and an oxygen concentration and temperature monitoring system, for simulation of spontaneous combustion of block coal （13-25 mm） covered with fine coal （0-3 mm）. A BP artificial neural network （ANN） with 150 training samples was gradually established over the course of our experiment. Heating time, relative position of measuring points, the ratio of fine coal thickness, artificial density, voidage and activation energy were selected as input variables and oxygen concentration and temperature of coal column as output variables. Then our trained network was applied to predict the trend on the untried experimental data. The results show that the oxygen concentration in the coal column could be reduced below the minimum still able to induce spontaneous combustion of coal - 6% by covering the coal pile with fine coal, which would meet the requirement to prevent spontaneous combustion of coal stockpiles. Based on the prediction of this ANN, the average errors of oxygen concentration and temperature were respectively 0.5% and 7 ℃, which meet actual tolerances. The implementation of the method would provide a practical guide in understanding the course of self-heating and spontaneous combustion of coal stockpiles.

关键词： loose coal neural netwOrk spontaneous combustion of coal oxygen concentration temperature prediction

Risk assessment and ranking of pesticide residues in Chinese pears

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Journal of Integrative Agriculture 2015年第11期14卷 2328-2339页

作者： LI Zhi-xia NIE Ji-yun YAN Zhen xu guo-feng LI Hai-fei KUANG Li-xue PAN Li-gang XIE Han-zhong WANG Cheng LIU Chuan-de ZHAO xu-bo guo Yong-ze Institute of Pomology Chinese Academy of Agricultural Sciences/Laboratory of Quality & Safety Risk Assessment for Fruit (Xingcheng)Ministry of Agriculture Beijing Research Center for Agricultural Standards and Testing Zhengzhou Institute of Pomology Chinese Academy of Agricultural Sciences Institute of Quality Standards & Testing Technology for Agro-Products Xinjiang Academy of Agricultural Sciences Yantai Academy of Agricultural Sciences Northwest A&F University Institute of Tianjin Agriculture Quality Standard and Testing Technology

The presence of pesticide residues in pears is a serious health concern. This study presents the results from a 2-year investigation （2013-2014） that used gas chromatography, GS/MS and UPLC/MS-MS to measure the levels of 104 pesti- cides in 310 pear samples. In 93.2% of the samples, 43 pesticides were detected, of which the maximum residue levels （MRLs） were exceeded in 2.6% of the samples. Multiple residues （two to eight compounds） were present in 69.7% of the samples; one sample contained nine pesticides and one sample contained 10. Only 6.8% of the samples did not contain residues. To assess the health risks, the pesticide residue data have been combined with daily pear consumption data for children and adult populations. A deterministic model was used to assess the chronic and acute exposures based on the Joint Meeting on Pesticide Residues （JMPR） method. A potential acute risk was demonstrated for children in the case of bifenthrin, which was found to be present at 105.36% of the acute reference dose （ARfD） value. The long- term exposure of the Chinese consumer to pesticide residues through the consumption of raw pears was far below the acceptable daily intake （ADI） criterion. Additionally, the matrix ranking scheme was used to classify risk subgroups of pesticides and pear samples. In general, 95.5% of samples were deemed to be safe and nine pesticides were classified as being of a relatively high risk. The findings indicated that the occurrence of pesticide residues in pears should not be considered a serious public health problem. Nevertheless, a more detailed study is required for vulnerable consumer groups, especially children. Continuous monitoring of pesticides in pears and tighter regulation of pesticide residue standards are recommended.

关键词： pear pesticide residue risk assessment intake risk ranking

Uniportal versus biportal video-assisted thoracoscopic sympathectomy for palmar hyperhidrosis

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Chinese Medical Journal 2009年第13期122卷 1525-1528页

作者： CHEN Yong-bing YE Wu YANG Wen-tao SHI Li guo xu-feng xu Zhong-hua QIAN Yong-yue Department of Cardiothoracic Surgery the Second Affiliated Hospital Soochow University Suzhou Jiangsu 215004 China

Background Video-assisted thoracoscopic sympathectomy had replaced open surgery. The aim of this study was to compare the outcomes of using a single port and two ports to perform video-assisted thoracoscopic sympathectomy for palmar hyperhidrosis. Methods Between April 2006 and February 2008, 20 cases underwent video-assisted thoracoscopic sympathectomy through one port （uniportal group） and 25 cases through two ports （biportal group）. The variables including the operating time, hospital stay, pain scores, postoperative complications, incidence of symptom recurrence and patient satisfaction were compared. The mean postoperative follow-up period was 11.5 months （range, 3-25 months）. Results The hands of all patients were warm and dry after operation. No conversion to open surgery was necessary, and no operative mortality was recorded in either group. The mean inpatient pain scores were significantly higher in the biportal group （1.2±0.6） than that in the uniportal group （0.8±0.5, P=0.025）. For the first three weeks after operation, four out of 20 （20%） patients in the uniportal group constantly suffered from mild or moderate residual pain while eight out of 25 （32%） cases in the biportal group （P=0.366）. Among them, two cases in the uniportal group and five cases in the biportal group need to take analgesics. Our mean operative time （bilateral sympathectomy） in the uniportal group （（39.5±10.0） minutes） was shorter than that in biportal group （（49.7±10.6） minutes, P=0.02）. There were no significant differences between two groups in terms of the mean hospital stay, compensatory sweating, and patient satisfaction. Two patients in the biportal group and three in the uniportal group experienced a unilateral pneumothorax. None of them required chest drainage. No patient experienced Homer＇s syndrome, and no recurrent symptoms were observed in either groups Conclusions Both uniportal and biportal video-assisted thoracoscopic sympathectomy are effective, safe, and minimally i

关键词： uniportal hyperhidrosis thoracic surgery, video-assisted sympathectomy

An Arc Incision Surgical Approach in Congenital Megaprepuce

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Chinese Medical Journal 2015年第4期128卷 555-557页

作者： Hou-Wei Lin Ling Zhang Hong-Quan Geng Xiao-Liang Fang guo-feng xu Mao-Sheng xu Wei Cai Department of Pediatric Urology Xinhua Hospital Shanghai 200092 China Department of Day Ward Renji Hospital Shanghai 200001 China

INTRODUCTION Congenital megaprepuce （CMP） is considered as a congenital penile malformation, which includes phimosis and severe ballooning of the redundant inner prepuce, conferring the typical aspect of concealed p... 详细信息

关键词： Foreskin Malformation Penis Reconstruction Surgical Technique

不同改良措施对卤阳湖盐碱地土壤性质及玉米产量的影响

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干旱地区农业研究 2019年第3期37卷 232-237页

作者：徐国凤同延安西北农林科技大学资源环境学院

利用农艺、生物、化学措施在陕西渭南市卤阳湖进行盐碱地改良田间试验,研究其对盐碱地的改良效果,选出适宜的当地盐碱土改良措施,为采取合理措施治理盐碱地提供依据。试验设9个处理,分别为对照、垄沟覆膜、平地覆膜、覆秸秆、生物有机... 详细信息

利用农艺、生物、化学措施在陕西渭南市卤阳湖进行盐碱地改良田间试验,研究其对盐碱地的改良效果,选出适宜的当地盐碱土改良措施,为采取合理措施治理盐碱地提供依据。试验设9个处理,分别为对照、垄沟覆膜、平地覆膜、覆秸秆、生物有机肥、羊粪、腐殖酸、石膏、过磷酸钙处理。结果表明:所有处理均能提高玉米产量,与对照相比,羊粪、腐殖酸、过磷酸钙处理显著提升玉米产量,增产幅度分别为15.2%、16.3%、14.6%。除了平地覆膜处理,其它处理的百粒重均显著高于对照,增幅在12.7%~19.1%之间。不同改良措施条件下,0~20 cm土层土壤养分均有不同程度增加,其中有机质增幅为0.6%~20.9%、速效氮增幅为30.6%~109.3%,速效磷增幅为4.5%~247.4%、速效钾增幅为23.4%~69.2%;土壤pH、全盐含量、钠离子均有不同程度的降低,其中垄沟覆膜与羊粪处理降低土壤pH、全盐含量、土壤Na +效果显著,pH分别降低2.18%、2.45%,脱盐率分别达到20.4%、20.2%。垄沟覆膜、覆秸秆、过磷酸钙处理的经济效益与对照相比分别提高了9.44%、12.88%、4.87%。针对该区域盐碱地现状,从降盐效果考虑,推荐垄沟覆膜、羊粪为最佳的改良措施;综合改良效果与经济效益,垄沟覆膜为最优改良措施。

关键词：盐碱地改良措施土壤性质脱盐率经济效益玉米产量