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The experimental study on combustion characteristics and emissions of a CMM fueled engine

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High Technology Letters 2011年第2期17卷 202-206页

作者：张欣 li Congxin xu jian Department of Power Mechanical Engineering Beijing Jiao Tong University Beijing 1000d4 P.R. China

In this paper, an experimental study on combustion characteristics and emissions of a single cylinder spark ignition engine fueled with coal-mine methane （CMM） is investigated under various loads. CMM is simulated by the compressed nature gas（ CNG）/nitrogen blend fuels. Based on experiment results, it is shown that under 0% - 35% nitrogen volume fraction in CNG/nitrogen blends, the maximum cylinder pressure, the maximum rate of pressure rise and the rate of heat release decrease, the flame propagation period increases, the center of heat release curve is closed to the top dead centre （TDC）markedly with the increase of nitrogen volume fraction. Meanwhile, the hydrocarbon （HC）, CO emissions increase, the NOx emission decreases apparently with the increase of nitrogen volume fraction.

关键词： coal-mine methane(CMM) engine combustion characteristic emission

Importance of incorporating systemic cerebroarterial hemodynamics into computational modeling of blood flow in intracranial aneurysm

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Journal of Hydrodynamics 2020年第3期32卷 510-522页

作者： Zhi-qiang Zhang li-jian xu Rong liu Xiao-sheng liu Bing-Zhao Fu-you liang School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Shanghai 200240China Institute of Textiles and Clothing The Hong Kong Polytechnic UniversityHong KongChina Department of Radiology Ren Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Neurosurgery Ren Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Institute for Personalized Medicine Sechenov UniversityMoscow 119991Russia

The importance of properly treating boundary conditions (BCs) in numerical simulation of hemodynamics in intracranial aneurysm (IA) has been increasingly recognized. In this study, we constructed three types of computational model for each IA to investigate how the outcome of numerical simulation is affected by the treatment of BCs. The first type of model (i.e., Type-A model) was obtained by applying 3-D hemodynamic modeling to the entire cerebral arterial network, with its solution being taken as the reference for evaluating the performance of the other two types of model (i.e., Type-B and Type-C models) in which 3-D modeling was confined to the aneurysm region. In addition, patient-specific 1-D models of the cerebral arterial network were developed to provide hemodynamic information for setting the inflow/outflow BCs of the 3-D models. Numerical tests on three IAs revealed that prescribing the outflow BCs of a localized 3-D aneurysm model based on 1-D model-simulated outflow division (i.e., Type-B model) instead of imposing the free outflow BC on all outlets (i.e., Type-C model) helped to improve the fidelity of the simulation of intra-aneurysmal hemodynamics, but could not guarantee a complete reproduction of the reference solution obtained by the Type-A model. Moreover, it was found that the outcome of hemodynamic simulation was more sensitive to the treatment of BCs when an aneurysm was located at arterial bifurcation rather than sidewall. These findings highlight the importance of taking into account systemic cerebroarterial hemodynamics in computational modeling of hemodynamics in IAs, especially those located at bifurcations.

关键词： Intracranial aneurysm systemic cerebroarterial hemodynamics boundary conditions computational model

Study on the pyrolysis behavior of Shendong Shangwan coal and its macerals concentrate

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Journal of Coal Science & Engineering(China) 2013年第1期19卷 75-82页

作者： Hua-lin liN Ke-jian li xu-wen ZHANG China Shenhua Coal to liquid and Chemical Shanghai Research Institute Shanghai 201108 China

The pyrolysis characteristics of Shendong Shangwan coal and its macerals concentrate were investigated using thermogravimetry （TG） coupled with mass spectrometry （MS）. The evolved gases were analyzed online by MS spectroscopy. The results of TG/DTG （derivative thermogravimetry） show ths vitrinite concentrate has greater weight loss rate and higher volatile yield than the other two samples. More light hydrocarbons C1-C5 are released from the vitfinite concentrate than from the Shendong Shangwan coal and inertinite concentrated in the process of pyrolysis. Three samples have similar shape curves of evolved gases of C2~C5 with different intensities. When the pyrolysis temperature was lower than 418℃, the amount of C6H6 evolved in the process of pyrolysis of inertinite concentrated was higher than that of raw coal and vitrinite concentrate. As the temperature rising, the production rate of C6H6 increased. Below 672℃, C6H6 evolution rate of vitrinite concentrate was far greater than the other two samples; the main evolution temperature range of C7H8 was 400℃ to 700℃ for the three samples. The amount of HE and H20 released first increased and then decreased with the temperature increase while more H2 released for pyrolysis of inertinite concentrated and more H20 released for the pyrolysis of vitrinite concentrate.

关键词： pyrolysis TG-MS macerals concentrate vitrinite concentrate

Cardiopulmonary bypass induced microcirculatory injury of the small bowel in rats

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World Journal of Gastroenterology 2009年第25期15卷 3166-3172页

作者： Guo-Hua Dong Chang-Tian Wang Yun li Biao xu jian-Jun Qian Hai-Wei Wu Hua Jing Department of Cardiothoracic Surgery Jinling Hospital Clinical Medicine School of Nanjing University Nanjing 210002 Jiangsu Province China

AIM： To investigate microvascular injury quantitatively in the small bowel with respect to cardiopulmonary bypass （CPB） and related mechanisms. METHODS： In 10 male SD rats, normothermic CPB was established and continued with a flow rate of 100-150 mL/kg per minute for 60 min, while another 10 sham-operated animals served as controls. An approximate 10-cm loop of the terminal ileum was exteriorized for observation by means of intravital fluorescence microscopy. The small bowel microcirculatory network including arterioles, capillaries, and collecting venules was observed prior to CPB, CPB 30 min, CPB 60 min, post-CPB 60 min and post-CPB 120 rain. The intestinal capillary perfusion, microvascular permeability and leukocyte adherence were also measured. RESULTS： The systemic hemodynamics remained stable throughout the experiment in both groups. In CPB animals, significant arteriolar vasoconstriction, blood velocity reduction and functional capillary density diminution were found. As concomitances, exaggerated albumin extravasation and increased leukocyte accumulation were also noted. These changes were more pronounced and there were no signs of restitution at the end of the observation period. CONCLUSION： CPB induces significant microcirculatory injury of the small bowel in rats. The major underlying mechanisms are blood flow redistribution and generalized inflammatory response associated with CPB.

关键词： Cardiopulmonary bypass Functional capillary density Intestinal microcirculation Intravital microscopy

Detection and Characterization of β-Lactam Resistance in Haemophilus parasuis Strains from Pigs in South China

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Journal of Integrative Agriculture 2012年第1期11卷 116-121页

作者： GUO li-li ZHANG jian-min xu Cheng-gang REN Tao ZHANG Bin CHEN Ji-dang liAO Ming Key Laboratory of Animal Disease Control and Prevention Ministry of Agriculture/Key Laboratory of Zoonoses Prevention and Control of GuangdongCollege of Veterinary MedicineSouth China Agricultural UniversityGuangzhou 510642P.R.China

To characterize the β-lactam resistance in veterinary clinical isolates of Haemophilus parasuis, 115 isolates were examined for the β-lactam resistance, the possession of β-lactamase, and the presence of β-lactamase genes. The genetic relationship among isolates was evaluated by pulsed-field gel electrophoresis （PFGE）. Overall, the commonly detected resistance phenotypes were resistant to ampicillin （26.09%）, penicillin （22.61%）, amoxicillin （21.74%）, cefazolin （14.78%）, cefaclor （12.17%）, and cefotaxime （6.96%）. These strains showed high minimal inhibitory concentration （MICs） to oxacillin. 20.87% strains produced β-lactamase, and 4.35% strains showed extended-spectrum b-lactamase （ESBL） phenotype. Moreover, 19 strains harboured bla genes including TEM-1 （n=5）, TEM-116 （n=10）, and ROB-1 （n=5）. Significantly, one strain possessed both TEM-1 and ROB-1, and displayed resistance to cefotaxime （MIC=8 mg L-1）. The epidemiological analysis of PFGE revealed high genetic diversity among bla-positive isolates. This work shows that TEM- and ROB-type β-lactamases are prevalent in H. parasuis isolates in China.

关键词： Haemophilus parasuis β-lactamase genes resistance pulsed-field gel electrophoresis

Imaging diagnosis of pancreato-biliary diseases: A control study

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World Journal of Gastroenterology 2003年第12期9卷 2824-2827页

作者： liang Zhong Qiu-Ying Yao Lei li jian-Rong xu Department of Radiology,Renji Hospital,Shanghai Second Medical University,Shanghai 200001,China Department of Radiology Renji Hospital Shanghai Second Medical University Shanghai 200001 China. zhong-liang@***

AIM: To evaluate the clinical value of various imageological methods in diagnosing the pancreato-biliary diseases and to seek the optimal ***: Eighty-two cases of pancreato-biliary diseases confirmed by surgery and pathology were analyzed. There were 38 cases of cholelithiasis, 34 cases of pancreato-biliary tumors and 10 other cases. The imageological methods included B-US, CT, ERCP, PTC, cross-sectional MRI and MR cholangiopancreatography (MRCP).RESULTS: The accuracy rate of MRCP in detecting the location of pancreato-biliary obstruction was 100 %. In differentiating malignant from benign obstruction, the sensitivity of the combination of MRCP and cross-sectional MRI was 82.3 %, the specificity was 93.8 %, and the accuracy rate was 89.0 % . The accuracy rate for determining the nature of obstruction was 87.8 %, which was superior to that of B-US (P=0.0000) and CT (P=0.0330),but there was no significant difference between direct cholangiopancreatography and the combination of MRCP and conventional MRI (P=0.6666).CONCLUSION: In most cases, MRCP can substitute direct cholangiopancreatography for diagnosis. The combination of MRCP and cross-sectional MRI should be considered as an important means in diagnosing the pancreato-biliary diseases, pre-operative assessment and post-operative follow-ups.

关键词：胰胆系疾病影像学诊断胆管阻塞临床研究 B-US ERCP

Preparation of NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu3+double-jacket microtubes for dual-mode fluorescent anti-counterfeiting

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Transactions of Nonferrous Metals Society of China 2020年第12期30卷 3333-3346页

作者： Yin CHEN Shao-wen XIE Chao TONG Hai-hu TAN li-jian xu Na li jian-xiong xu Hunan Key Laboratory of Biomedical Nanomaterials and Devices College of Life Sciences and ChemistryHunan University of TechnologyZhuzhou 412007China Key Laboratory of Electrochemical Green Metallurgy Technology of Hunan Higher Education Institutions College of Metallurgy and Materials EngineeringHunan University of TechnologyZhuzhou 412007China

Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal *** is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent *** growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+*** formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening *** as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.

关键词： lanthanide-doped fluoride core-shell structure dual-mode luminescence inkjet printing anti- counterfeiting

Delayed right-sided diaphragmatic hernia with severe ：raniocerebral trauma

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Chinese Medical Journal 2010年第7期123卷 974-976页

作者： TANG Hua WU li-hui li jian-qiu xu Zhi-fei Department of Thoracic and Cardiovascular Surgery Shanghai Changzheng Hospital Second Military Medical University Shanghai 200003 China

Diaphragmatic hernia （DH） is an uncommon result of trauma, but presents a severe problem in patients With multiple injuries. Right-sided DH is rare, owing to the protection of the liver and strength of the right hem... 详细信息

关键词： trauma diaphragmatic hernia craniocerebral trauma

Effect of combination of extracts of ginseng and ginkgo biloba on acetylcholine in amyloid beta-protein-treated rats determined by an improved HPLC

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Acta Pharmacologica Sinica 2004年第9期 16-21页

作者： jian-xun liU, Wei-hong CONG, li xu, jian-nong WANG Research Center, Xiyuan Hospital, China Academy of Traditional Chinese Medicine, Beijing 100091, China

AIM: To determine the concentration of acetylcholine (ACh) in amyloid beta-protein (Aβ) treated rats and offer a method determining ACh as well. METHODS: A 1-month combination of extrats of ginseng and ginkgo biloba (Naoweikang) ig administration to rats was performed daily after bilateral injection of Aβ1-40 (4 g/L, 1μL for each side) into hippocampus. After

关键词： ginseng ginkgo biloba acetylcholine high pressure liquid chromatography amyloid beta-protein