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Degradation of MTBE and TBA by a new isolate from MTBE-contaminated soil

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Journal of Environmental Sciences 2007年第9期19卷 1120-1124页

作者： ZHANG Rui-ling HUANG Guo-qiang liAN Jing-yan li xin-gang School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China National Engineering Research Center for Distillation Technology Tianjin 300072 China School of Chemistry and Chemical Engineering Tianjin University of Technology Tianjin 300191 China

Methyl ten-butyl ether （MTBE）, a gasoline additive, possesses serious problems to the environmental health. In the present study, a bacterial culture named A-3 which could effectively degrade MTBE was isolated from the MTBE contaminated soil. The isolate was identified as Chryseobacterium sp., a new species capable of degrading MTBE. In order to enhance its degradation ability, selected environment factors were investigated. The results showed that the optimal temperature was in the range of 25-30℃, the pH was 7.0, the inoculum size was 2 × 10^8 CFU/ml and the optimal concentration of MTBE was from 50 to 100 mg/L. The maximum MTBE utilization rate （Vmax） was 102 nmol MTBE/（mg cell protein.h）. Furthermore, it was found that the isolate could also degrade tert-butyl alcohol （TBA）. The degradation rates of TBA were much faster than those of MTBE. The additional TBA would lead to the decrease of the initial MTBE degradation rate and the inhibitory effect of TBA increased with the increase of TBA concentration. Similar protein profiles at least seven peptides were demonstrated after SDS-PAGE analysis of crude extracts obtained from the cells growing in MTBE and TBA culture.

关键词： methyl ten-butyl ether (MTBE) biodegradation ten-butyl alcohol (TBA)

Pharmacokinetic interaction of Forsythia suspensa extract and azithromycin injection after single and co-intravenous administration in rats

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Chinese Journal of Natural Medicines 2020年第3期18卷 234-240页

作者： li xin-gang NI Jian SHEN Su WANG Xiao-Ping TIAN Jing-Chen Department of Pharmacy Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 100102China Department of Pharmacy Shaanxi Provincial Hospital of Traditional Chinese MedicineXian 710003China Department of Pharmacy Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China

Azithromycin and Chinese medicine forsythia are often used together to treat pediatric mycoplasma infections in China. We aimed to investigate the pharmacokinetic interaction of Forsythia suspensa extract and azithromycin after single and co-intravenous administration in rats. Male Sprague-Dawley rats received single(Forsythia suspensa extract or azithromycin) treatment or co-administration of Forsythia suspensa extract and azithromycin. Blood samples were collected at scheduled times, and drug concentrations were determined by HPLC-UV or HPLC-MS/MS methods. Both non-compartmental analyses and nonlinear mixed-effects modeling approaches were applied to fit pharmacokinetic data and evaluate the impact of co-administration. Pharmacokinetic analysis showed that the area under the curve of azithromycin and forsythiaside increased, and clearance decreased significantly(P < 0.05),after co-administration. The in vivo behavior of both azithromycin and forsythiaside could be appropriately described by the two-compartmental model. The final population pharmacokinetic model indicated that co-administration decreased the central volume of azithromycin and forsythiaside clearance significantly. Co-administration of Forsythia suspensa extract and azithromycin significantly decreased the clearance and increased exposure for both drugs. Pharmacokinetic data suggest that drug co-administration may increase efficiency.

关键词： Forsythia suspensa Azithromycin Forsythiaside Co-administration Non-compartmental analysis Population pharmacokinetics Pharmacokinetic interaction

Modeling the Migration of Soluble Methanol in Unsaturated Soil Zone

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Pedosphere 2007年第3期17卷 366-372页

作者： li Hong li xin-gang HUANG Guo-Qiang JIANG Bin School of Chemical Engineering and Technology Tianjin University Tianjin 300072 （China） National Engineering Research Center for Distillation Technology Tianjin 300072 （China）

A combined model of solute transport and water flow was developed to simulate the migration of methanol, a soluble organic chemical, in unsaturated soil zone. The solute transport equation considered convective-dispersive transport in the liquid phase as well as diffusion in the gas phase. The effect of rainfall and evapotranspiration on transport was considered at the boundary conditions of the governing equations. Data on the characteristics of a loam soil and the climatic conditions in southern California were also introduced to compare the results with those from a study in the USA in which the profiles of methanol distribution and water content in the soil zone at different times had been depicted. This comparison showed that there was good agreement between the two studies. The results showed that methanol contamination reached a depth of about 250 cm after 8 760 h. In contrast, if rainfall and evapotranspiration were not considered, the depth was only about 140 cm. The model therefore confirmed that rainfall strongly affected solute transport.

关键词： evapotranspiration methanol rainfall solute transport model

Characterization and distribution of polycyclic aromatic hydrocarbon in sediments of Haihe River, Tianjin, China

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Journal of Environmental Sciences 2007年第3期19卷 306-311页

作者： JIANG Bin ZHENG Hai-long HUANG Guo-qiang DING Hui li xin-gang SUO Hong-tu li Rui School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Jinzhou Petrochemical Co. Designing Institute Jinzhou 121001 China

In this study sediment samples were collected from 13 sites of Haihe River in Tianjin City, China, sixteen of priority polycyclic aromatic hydrocarbons （PAHs） listed in USEPA were analyzed by means of GC-MS. The total concentrations of PAH ranged from 774.81 to 255371.91 ng/g dw, and two to four rings of PAHs were dominant in sediment samples. Molecular ratios, such as phenanthrene/anthracene, fluoranthene/pyrene and low-molecular-weight PAH/high-molecular-weight PAH, were used to study the possible sources of pollution. It indicated a mixed pattern of parolytic and petrogenic inputs of PAHs in sediments in Haihe River. The petrogenic PAHs may be mainly derived from the leakage of refined products, e.g., gasoline, diesel fuel and fuel oil vehicle traffics or gas stations from urban area. The pyrolytic PAHs might be from the discharge of industrial wastewater and the emission of atmospheric particles from petrochemical factories. In addition, the levels of PAHs in the urban and industrial areas are far beyond the values reported from other rivers and marine systems reported. This situation may be due to polluted discharging from some petrochemical industrial manufactories and worse traffic conditions in Tianjin.

关键词： PAHs Haihe River sediments Tianjin

Persistent organochlorine residues in sediments of Haihe River and Dagu Drainage River in Tianjin, China

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Journal of Environmental Sciences 2005年第5期17卷 731-735页

作者： DING Hui li xin-gang liU Hun WANG Jun SHEN Wei-ran SUN Yi-chao SHAO Xiao-long School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Tianjin Environmental Protection Bureau Tianjin 300191 China

Persistent organochlorine compounds were analyzed by means of GC-ECD in surface sediment samples from two selected rivers in Tianjin, Haihe River and Dagu Drainage River. A total of 16 surface sediment sites were selected along the both rivers. The frequency of detection of T-HCH and T-DDT in sediment samples both was up to 100%, which illustrated that the contamination of HCH and DDT was widespread in Haihe and Dagu Drainage Rivers. Results indicated that the concentrations of various pesticides in sediments from Haihe River were in the range of 3.30-75.96 ng/g dw for T-HCH and 1.57-211.57 ng/g dw for T-DDT. Compared with Haihe River, Dagu Drainage River was contaminated by HCHs and DDTs along the all locations and the values of T-HCH and T-DDT residues in sediments ranged from 2.30 to 124.61 ng/g dw and from 11.28 to 237.30 ng/g dw, respectively, The possible pollution sources were analyzed through monitoring results of organochlorine pesticides（OCPs） residues in sediments from the two rivers. The investigation also indicated that HCH was still used as pesticide in Tianjin partial area.

关键词： Haihe River Dagu Drainage River sediment OCPs DDT HCH

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-Tang liang Yu-gang Ma xin-li Sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

Ablation behaviour and mechanical performance of ZrB_(2)-ZrC-SiC modified carbon/carbon composites prepared by vacuum infiltration combined with reactive melt infiltration

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新型炭材料（中英文） 2024年第4期39卷 633-644页

作者： ZHANG Jia-ping SU Xiao-xuan li xin-gang WANG Run-ning FU Qian-gang Shaanxi Key Laboratory of Fiber Reinforced light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China

The development of advanced aircraft relies on high performance thermal-structural materials,and carbon/carbon com-posites(C/C)composited with ultrahigh-temperature ceramics are ideal ***,the traditional routes of compositing are either inefficient and expensive or lead to a non-uniform distribution of ceramics in the *** with the traditional C/C-ZrC-SiC composites prepared by the reactive melt infiltration of ZrSi_(2),C/C-ZrB_(2)-ZrC-SiC composites prepared by the vacuum infiltration of ZrB_(2) combined with reactive melt infiltration have the higher content and more uniform distribution of the introduced ceramic *** mass and linear ablation rates of the C/C-ZrB_(2)-ZrC-SiC composites were respectively 68.9%and 29.7%lower than those of C/C-ZrC-SiC composites prepared by reactive melt *** ablation performance was improved because the volatilization of B_(2)O_(3),removes some of the heat,and the more uniformly distributed ZrO_(2),that helps produce a ZrO2-SiO2 continu-ous protective layer,hinders oxygen infiltration and decreases ablation.

关键词： C/C composites ZrB_(2)-ZrC-SiC Vacuum filtration Reactive melt infiltration Ablation.

Percutaneous microballoon compression for trigeminal neuralgia

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Chinese Medical Journal 2007年第3期120卷 228-230页

作者： liU Hong-bing MA Yi ZOU Jian-jun li xin-gang Department of Neurosurgery Qilu Hospital Shandong UniversityJinan 250012 China Department of Neurosugery Liaoning Provincial HospitalShenyang 110001 China

Background Percutaneous microballoon compression （PMC） for trigeminal neuralgia is an important therapeutic method. The aim of this study was to review the effects of PMC for trigeminal neuralgia in 276 patients. Methods From December 2000 to May 2003, 276 patients with trigeminal neuralgia were treated with PMC. The course of the disease ranged from 3 months to 38 years. Under the guidance of C-arm X-ray, 14# needle was placed into the foramen ovale using the classical Hakanson＇s technique. Fogarty balloon catheter was navigated into the Meckel＇s cave tenderly. A small amount of Omnipaque was slowly injected to inflate the balloon and compress the trigeminal ganglion for 3 to10 minutes. Results A total of 290 PMC were performed on the 276 patients. Among them, 252 had immediate relief from pain. The patients were followed up for a mean of 18.7 months （range, 4 to 32）, 14 of them had a recurrence. Of the 14 patients, 12 were re-operated with PMC, and the pain was all controlled successfully. Conclusions PMC is an effective and technically simple method for trigeminal neuralgia. For older patients with trigeminal neuralgia, it may be the first choice.

关键词： trigeminal nerve trigeminal neuralgia percutaneous microballoon compression

多优先级多车种动态应急交通网络反流策略研究

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交通运输系统工程与信息 2022年第6期22卷 258-268页

作者：刘正李新刚郑州航空工业管理学院管理工程学院郑州450046 郑州航空工业管理学院航空经济发展河南省协同创新中心郑州450046 北京交通大学交通运输学院北京100044 北京交通大学综合交通运输大数据应用技术交通运输行业重点实验室北京100044

危化品爆炸泄漏和火灾爆炸等局部突发事件下,疏散车辆与救援车辆在路网上通行的优先级具有差异性。为研究多优先级多车种动态应急交通网络协调优化问题,本文根据多车种的优先级差异性,松弛路段传输模型,模拟疏散和救援交通在路网上的动... 详细信息

危化品爆炸泄漏和火灾爆炸等局部突发事件下,疏散车辆与救援车辆在路网上通行的优先级具有差异性。为研究多优先级多车种动态应急交通网络协调优化问题,本文根据多车种的优先级差异性,松弛路段传输模型,模拟疏散和救援交通在路网上的动态加载过程,引入交叉口冲突转向消除与道路反流约束;考虑到优先通行车辆的反流策略会占用低优先级车辆的道路通行能力,设置救援交通的逆行路段数限制。设计分阶段优化方法求解多优先级多车种动态应急交通网络协调优化的多目标混合整数线性规划模型(MPCDETN-MMILP)。最后,以Nguyen-Dupuis路网为例,分析优先通行车辆使用的逆行路段数对疏散和救援交通的影响。算例结果表明:救援交通逆行路段数和对救援车辆迅速到达受灾区域的提升存在上限,且这种提升趋势是逐渐变缓的,而对疏散车辆迅速到达安全区域的抑制呈现波动式的增加趋势;救援交通逆行路段数对救援优先的疏散和救援交通运行优化效果有较大协调作用;连接受灾区域和外部救援场站,且可构成最短径路的路段更会被选择为救援交通逆行路段。

关键词：城市交通多优先级多车种动态应急交通网络反流策略协调优化

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