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Identification of odorous compounds in reclaimed water using FPA combined with sensory GC-MS

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Journal of Environmental Sciences 2011年第10期23卷 1600-1604页

作者： Zhiming yan yu zhang Jianwei yu Hongying yuan Min yang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085 China.

Odorous compounds in the influent of a reclaimed water treatment plant （RWTP）, consisting of coagulation, sedimentation, continuous micro-filtration （CMF）, and chlorination in succession, in a north China city, were identified by combining flavor profile analysis （FPA） with sensory gas chromatograph-mass spectrometry （GC-MS）. The sewery/swampy/septic odor with an odor intensity of 6.4 was found to be the major odor group in the RWTP influent, and the existence of well-known odorant including dimethyl disulfide, dimethyl trisulfide, indole and skatole were confirmed using GC-MS. The result of a spiking test showed that the intensity （3.6） of the sewery/swampy/septic odor caused by these four chemicals contributed to over 50% of the odor intensity of the influent. The FPA intensity for sewery/swampy/septic odor in the RWTP effluent was 3.8, showing that the treatment process was not efficient for the removal of odorants, particularly indole and skatole.

关键词： sewery/swampy/septic odor reclaimed wastewater flavor profile analysis sensory-GC-MS analysis

Oxidative stress and hypoxia-induced factor 1α expression in gastric ischemia

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World Journal of Gastroenterology 2011年第14期17卷 1915-1922页

作者： Tao Wang yu-Fang Leng yan zhang Xing Xue yu-Qing Kang yue zhang Department of Anesthesiology The First Hospital of Lanzhou University Lanzhou 73000 Gansu Province China

AIM:To investigate the relation of reactive oxygen species (ROS) to hypoxia induced factor 1α (HIF-1α) in gastric ischemia. METHODS:The animal model of gastric ischemia reperfusion was established by placing an elastic rubber band on the proximal part of the bilateral lower limb for ligature for 3 h and reperfusion for 0,1,3,6,12 or 24 h. Ischemic post-conditioning,three cycles of 30-s reperfusion and 30-s femoral aortic reocclusion were conducted before reperfusion. Histological and immunohistochemical methods were used to assess the gastric oxidative damage and the expression of HIF1-α in gastric ischemia. The malondialdehyde (MDA) content and superoxide dismutase (SOD),xanthine oxidase (XOD) and myeloperoxidase (MPO) activities were determined by colorimetric assays. RESULTS:Ischemic post-conditioning can reduce post-ischemic oxidative stress and the expression of HIF-1α of gastric tissue resulting from limb ischemia reperfusion injury. MDA,SOD,XOD and MPO were regarded as indexes for mucosal injuries from ROS,and ROS was found to affect the expression of HIF-1α under gastric ischemic conditions. CONCLUSION:ROS affects HIF-1α expression under gastric ischemic conditions induced by limb ischemia reperfusion injury. Therefore,ROS can regulate HIF-1α expression in gastric ischemia.

关键词： Oxidative stress Reactive oxygen species HIF-1α expression Gastric ischemia Limb ischemia reperfusion

Therapeutic endoscopic retrograde cholangiopancreatography in a patient with asplenia-type heterotaxy syndrome:A case report

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World Journal of Gastrointestinal Surgery 2024年第11期16卷 3578-3583页

作者： yu-yan zhang Jiang Ruan yan Fu Department of Gastroenterology The Second Affiliated Hospital of Kunming Medical UniversityKunming 650101Yunnan ProvinceChina

BACKGROUND Asplenia-type heterotaxy syndrome(HS)is rare and refers to visceral malposition and *** is associated with a high infant mortality rate due to cardiac anomalies,and related digestive endoscopic interventions are poorly *** the improved long-term prognosis of these individuals after modern cardiac surgery,intra-abdominal anomalies have become increasingly *** SUMMARY Herein,we report successful endoscopic retrograde cholangiopancreatography(ERCP)in a 14-year-old male with asplenia-type HS that involved unique imaging findings and technical *** anatomic anomalies included complex congenital heart disease,midline liver placement,an absent spleen,a left-sided inferior vena cava,and dextroposition of the stomach and *** suffered from choledocholithiasis with obstructive jaundice,and the stone was successfully extracted with a basket following endoscopic papillary balloon *** Although anatomic anomalies in HS increase the degree of technical difficulty when performing ERCP,they can be safely managed by experienced endosco-pists,as illustrated by the present *** these variations with imaging modalities and being aware of them before initiating an invasive intervention are crucial to preventing potential complications.

关键词： Heterotaxy Asplenia Situs ambiguous Endoscopic retrograde cholangiopan-creatography Case report

Sensor/Actuator Faults Detection for Networked Control Systems via Predictive Control

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International Journal of Automation and computing 2013年第3期10卷 173-180页

作者： yu-yan zhang Jun-Ling zhang Xiao-yuan Luo Xin-Ping Guan Institute of Electrical Engineering Yanshan University

Quantized fault detection for sensor/actuator faults of networked control systems （NCSs） with time delays both in the sensor-to-controller channel and controller-to-actuator channel is concerned in this paper. A fault model is set up based on the possible cases of sensor/atuator faults. Then, the model predictive control is used to compensate the time delay. When the sensors and actuators are healthy, an H stability criterion of the state predictive observer is obtained in terms of linear matrix inequality. A new threshold computational method that conforms to the actual situation is proposed. Then, the thresholds of the false alarm rate （FAR） and miss detection rate （MDR） are presented by using our proposed method, which are also compared with the ones given in the existin~ literatures. Finally, some numerical simulations are shown to demonstrate the effectiveness of the proposed method.

关键词： Networked control system fault detection false alarm rate (FAR) miss detection rate (MDR) predictive control.

Hypersingular parameterized Marcinkiewicz integrals with variable kernels on Sobolev and Hardy-Sobolev spaces

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 420-430页

作者： CHEN Jie-cheng yu Xiao zhang yan-dan WANG Hui Department of Mathematics Zhejiang University Hangzhou 310027 China

Let α≥ 0 and 0 〈 ρ ≤ n/2, the boundedness of hypersingular parameterized Marcinkiewicz integrals μΩ,α^ρ with variable kernels on Sobolev spaces Lα^ρ and HardySobolev spaces Hα^ρ is established.

关键词： parameterized Marcinkiewicz integral variable kernel Hardy-Sobolev space L^α-Dini condition

Study on the Relationship between Tourist Influence and Residents' Sense of Community:An Empirical Study from Changdao Countyin Shandong Province

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Chinese Journal of Population,Resources and Environment 2012年第1期10卷 101-104页

作者： yu Wei zhang yan School of Business Management Shandong University of Finance Jinan Shandong 250014 China

Residents' sense of community is an important prerequisite to promote the development of *** has significant influence on residents' sense of *** empirical study from Changdao shows that economy and life conflict caused by tourism can affect neighborhood-friendly and community participation ***,environment and social services from tourism can significantly affect community association,community care and place ***,the regional managers should pay attention to allocate revenues in the residents fairly and protect own culture to avoid the negative impact from tourism.

关键词： tourism residents sense of community

Diffusion coefficients of natural gas in foamy oil systems under high pressures

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Petroleum Science 2015年第2期12卷 293-303页

作者： yan-yu zhang Xiao-Fei Sun Xue-Wei Duan Xing-Min Li College of Petroleum Engineering China University of Petroleum School of Geosciences China University of Petroleum The Department of Chemical and Petroleum Engineering University of Calgary Research Institute of Petroleum Exploration and Development PetroChina

The diffusion coefficient of natural gas in foamy oil is one of the key parameters to evaluate the feasibility of gas injection for enhanced oil recovery in foamy oil reservoirs. In this paper, a PVT cell was used to measure diffusion coefficients of natural gas in Venezuela foamy oil at high pressures, and a new method for deter- mining the diffusion coefficient in the foamy oil was de- veloped on the basis of experimental data. The effects of pressure and the types of the liquid phase on the diffusion coefficient of the natural gas were discussed. The results indicate that the diffusion coefficients of natural gas in foamy oil, saturated oil, and dead oil increase linearly with increasing pressure. The diffusion coefficient of natural gas in the foamy oil at 20 MPa was 2.93 times larger than that at 8.65 MPa. The diffusion coefficient of the natural gas in dead oil was 3.02 and 4.02 times than that of the natural gas in saturated oil and foamy oil when the pressure was 20 MPa. However, the gas content of foamy oil was 16.9 times higher than that of dead oil when the dissolution time and pressure were 20 MPa and 35.22 h, respectively.

关键词： Foamy oil Diffusion coefficient - Heavy oil Gas injection High pressure

Theoretical Studies on Adsorption Sites and States of O and N on Ni(311)

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Chemical Research in Chinese Universities 2009年第1期25卷 98-101页

作者： DIAO Zhao-yu zhang yan zhang Xue-na WANG Ze-xin WANG Zhong-ni Chemistry Department Shandong Normal University Jinan 250014 P. R. China

The adsorption of O and N atoms on the Ni（311） surface was investigated by the 5-parameter Morse potential（5-MP） method in detail. For the O-Ni（311） system, there are three surface adsorption states and the fcc-3-fold site is metastable; the frequency of 75 meV[67 meV in high resolution electron energy loss spectroscopy（HREELS） experiment] is attributed to the vibration at the hcp-3-fold site. For the N-Ni（311） system, however, there are only two surface adsorption states（no surface adsorption state was calculated atfcc-3-fold site）. In addition, subsurface states were predicted and all critical characteristics were obtained for the two systems.

关键词： 5-Parameter Morse potential O-Ni(311) system N-Ni(311) system Adsorption

Influence of education and working background on physicians' knowledge of secondary prevention guidelines for coronary heart disease: results from a survey in China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第3期13卷 231-238页

作者： yan-jun GONG Tao HONG Jie JIANG Rong-hui yu yan zhang Zhao-ping LIU Yong HUO Department of Cardiology Peking University First Hospital Beijing 100034 China

Background and objective： In clinical practice, the standard of secondary prevention for coronary heart disease （CHD） is quite disappointing in China. The physicians＇ shortage of knowledge of secondary prevention guidelines is thought to be a key factor contributing to the inadequate and delayed translation of guidelines into clinical practice. The purpose of this study is to investigate the influence of physicians＇ characteristics, including their educa- tion and work experience, on their knowledge of secondary prevention in China. Methods： A representative ques- tionnaire survey was made of physicians from cardiology departments in 35 tertiary hospitals in China. The survey contained 19 questions on knowledge of guideline recommendations for the secondary prevention of CHD. We col- lected basic information about the physicians, including their educational degree, clinical practice duration/work experience and geographic region. Results： In total, 864 physicians participated in the survey. Eight hundred and thirty-seven completed questionnaires were analyzed. For 6 of the 19 questions, physicians with a postgraduate degree were more likely to answer correctly than those without such a degree. For 11 of the 19 questions, physicians with more than three years＇ clinical experience were more likely to answer correctly than those who had less than three years＇ experience. For 5 of the 19 questions, *** eastern areas were more likely to answer correctly than those from mid/western areas. The mean total score of correct answers to the questionnaire was 11.69 points. Edu- cational degree and clinical practice duration affected total scores significantly while practice location did not （β=0.500, P=0.004; ,β=0.979, P=0.000; and 8=0.228, P=0.162, respectively）. Even if a relatively low score of 12 is taken as a threshold level of acceptable knowledge （defined as a pass）, the pass rate of all physicians was only 53.9%. Educational degree and clinical practice durat

关键词： Coronary heart disease Secondary prevention Guidelines Survey