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Advances in emission control of diesel vehicles in China

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Journal of Environmental Sciences 2023年第1期123卷 15-29页

作者： Guangyan Xu Wenpo shan Yunbo Yu Yulong shan Xiaodong Wu Ye Wu Shaojun Zhang Liqiang he Shijin Shuai Hailong Pang Xuefeng Jiang heng Zhang Lei Guo Shufen Wang feng-Shou Xiao Xiangju Meng feng Wu Dongwei Yao Yan Ding Hang Yin Hong he Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Institute of Urban Environment Chinese Academy of SciencesXiamen 361021China Tsinghua University Beijing 100084China Army Military Transportation University Tianjin 300161China Dongfeng Motor Corporation Wuhan 430101China China National heavy Duty Truck Group Company Limited Jinan 250000China Zhejiang University Hangzhou 310027China Chinese Research Academy of Environmental Sciences Beijing 100012China

Diesel vehicles have caused serious environmental problems in ***,the Chinese government has launched serious actions against air pollution and imposed more stringent regulations on diesel vehicle emissions in the latest China VI *** fulfill this stringent legislation,two major technical routes,including the exhaust gas recirculation(EGR)and high-efficiency selective catalytic reduction(SCR)routes,have been developed for diesel ***,complicated aftertreatment technologies have also been developed,including use of a diesel oxidation catalyst(DOC)for controlling carbon monoxide(CO)and hydrocarbon(HC)emissions,diesel particulate filter(DPF)for particle mass(PM)emission control,SCR for the control of NOx emission,and an ammonia slip catalyst(ASC)for the control of unreacted *** to the stringent requirements of the China VI standard,the aftertreatment system needs to be more deeply integrated with the engine *** the future,aftertreatment technologies will need further upgrades to fulfill the requirements of the near-zero emission target for diesel vehicles.

关键词： Diesel vehicles Legislation Emission control Aftertreatment system Nitrogen oxides Particulate matter

Psychological Status and Warfarin Therapy in Patients after Valve Replacement during the COVID-19 Pandemic:A Cross-sectional Study

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Current Medical Science 2024年第4期44卷 686-691页

作者： Xiao-yan CheN Sheng he Zhen TAN feng GAO Hui JIANG Lu CheN Li YANG Yu-shan LIU Si-yi he Department of Cardiovascular Surgery The General Hospital of Western Theater CommandChengdu610083China Department of Digestive Medicine The General Hospital of Western Theater CommandChengdu610083China Department of General Surgery The General Hospital of Western Theater CommandChengdu610083China

Objective The standardization of warfarin anticoagulant therapy is the key to lifelong treatment for patients after heart valve *** present study explored the possible risk factors for anxiety and depression during the coronavirus disease 2019(COVID-19)pandemic and analyzed the influence of psychological state on medication *** Eligible patients received a web-based questionnaire survey via the Wenjuanxing platform during outpatient *** was evaluated by the Self-Rating Depression Scale(SDS).Anxiety was evaluated by the Self-Rating Anxiety Scale(SAS).Medication adherence was evaluated by the Morisky *** A total of 309 patients(aged 52.2±11.4 years)were included in the present *** SDS score of all included patients was 36.9±9.4 points,of which 11(3.6%)patients were diagnosed as having *** SAS score of all included patients was 43.1±9.3 points,of which 71(23%)patients were diagnosed as having *** patients(2.3%)had both anxiety and *** regression analysis revealed that only monthly income was an independent influencing factor for *** anxiety,patients who underwent repeated operations had a 2.264-fold greater risk,and patients who received combination medication had a 2.140-fold greater *** bleeding events and coagulation disorders could be observed in patients with anxiety,depression or *** anxiety occurred,patients showed worse medication ***,depression had no significant effect on medication *** During the COVID-19 pandemic,the detection rate of mental illnesses such as anxiety and depression was high,which seriously affected the medication safety of *** of its influencing factors will provide a reference for further standardized regulation of warfarin anticoagulant therapy after valve replacement.

关键词： Warfarin COVID-19 valve replacement depression anxiety

An improved method for evaluating the rotational speed stability of a hydro-viscous clutch in mixed lubrication

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Friction 2015年第1期3卷 47-55页

作者： Shou-Wen YAO Qian LIU Hong-Wei CUI shan-shan feng School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Vehicular Transmission Beijing Institute of TechnologyBeijing 100081China School of Mechanical Engineering Taiyuan University of TechnologyTaiyuan 030024China

Rotational speed stability is an important evaluation indicator of the performance of a hydro-viscous clutch(HVC).To improve the rotational speed stability of HVCs in mixed lubrication and the running condition of the friction pairs,the speed stability of an HVC in mixed lubrication was *** this end,the friction coefficients of both copper-based and paper-based friction pairs were experimentally tested using an MM1000-III wet friction ***,a torsional vibration model of the system is *** phase plane analysis method is applied to evaluate the stability of the torsional vibration model,where a critical negative gradient(CNG)is *** results show that the friction coefficient in mixed lubrication is an important parameter for the stability of the rotational *** system will be unstable when the negative gradient of the friction coefficient-slip speed is larger than the *** to the definition of the CNG,suggestions regarding choice of friction pairs are made to improve the rotational speed stability of an HVC in mixed lubrication.

关键词： Hydro-viscous clutch mixed lubrication speed stability negative gradient of friction coefficient-slipping speed torsional vibration model critical negative gradient

Effect of Oxide Scale on Interfacial heat Transfer during Slab Hot Rolling

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Journal of Iron and Steel Research International 2002年第2期9卷 21-23页

作者： ZHOU Wei-hai DU feng-shan Yanshan University

The environmental conditions in steel industry were discussed in detail. It was also pointed out that it was necessary to reduce the quantity of waste generated and discharged by improving the raw material, energy structure and consumption rate, and reinforcing the waste control and management. At the same time, the relevant mathematical models of environmental impact were set up on the basis of raw material consumption, energy consumption and waste generation and discharge in different technical routes of steelmaking. The result showed that the production route of DR iron clearly has more environmental advantages over that of BF hot metal.

关键词： iron steel production route environmental impact mathematical model

Serum 25(OH)D and Lipid Levels in Chinese Obese and Normal Weight Males before and after Oral Vitamin D Supplementation

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Biomedical and Environmental Sciences 2013年第10期26卷 801-807页

作者： ZHOU Ji Chang ZHU Yu Mei GUO Ping CheN Zheng XIE feng Zhu LIU Xiao Li he shan Molecular Biology Laboratory Shenzhen Center for Chronic Disease Control health Service Center of Shuiku Community Shenzhen Center for Chronic Disease Control

Objective To study the effect of oral vitamin D （VD） supplementation on VD status and serum lipid in Chinese obese and healthy normal-weight men. Methods Twenty-one obese men with their body mass index （BMI）〉28 kg/m2 served as an obese group and 22 healthy normal-weight men with their BMI〈24 kg/m2 served as a control group in this study. After they were given 50 000 IU of oral VD, once a week for 8 weeks, the serum 25-hydroxyvitamin D [25（OH）D] concentration was measured with an enzyme-immunoassay kit. Results After oral VD supplementation, the serum 25（OH）D concentration significantly increased from 46.1＋9.1 nmol/L to 116.7_＋20.3 nmol/L in the obese subjects （P〈O.01） and from 52.8_＋17.8 nmol/L to 181.3_＋30.2 nmol/L in the control ones （P=0.13）. The serum high-density lipoprotein cholesterol （HDL-C） level was reduced within the normal reference range in the obese group. However, no significant change was observed in the level of other serum lipids （triglycerides, total cholesterol, and low-density lipoprotein cholesterol） in either of the two groups. Conclusion The effect of high-dose oral VD supplementation is weaker on VD status in the obese group than in the control group. High-dose oral VD supplementation has no side effect on serum lipid level in obese and control groups.

关键词： Vitamin D Obesity Serum 25(OH)D Serum lipid

Well production optimization using streamline features-based objective function and Bayesian adaptive direct search algorithm

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Petroleum Science 2022年第6期19卷 2879-2894页

作者： Qi-Hong feng shan-shan Li Xian-Min Zhang Xiao-Fei Gao Ji-Hui Ni School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina shandong Institute of Petroleum and Chemical Technology Dongying257061ShandongChina CNOOC China Limited Shenzhen BranchShenzhen518000GuangdongChina

Well production optimization is a complex and time-consuming task in the oilfield *** combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well *** method spends most of computing time in objective function evaluation by reservoir numerical simulator which limits its optimization *** improve optimization efficiency,a well production optimization method using streamline features-based objective function and Bayesian adaptive direct search optimization(BADS)algorithm is *** new objective function,which represents the water flooding potential,is extracted from streamline *** only needs to call the streamline simulator to run one time step,instead of calling the simulator to calculate the target value at the end of development,which greatly reduces the running time of the *** the well production optimization model is established and solved by the BADS *** feasibility of the new objective function and the efficiency of this optimization method are verified by three *** demonstrate that the new objective function is positively correlated with the cumulative oil *** the BADS algorithm is superior to other common algorithms in convergence speed,solution stability and optimization ***,this method can significantly accelerate the speed of well production optimization process compared with the objective function calculated by other conventional *** can provide a more effective basis for determining the optimal well production for actual oilfield development.

关键词： Well production Optimization efficiency Streamline simulation Streamline feature Objective function Bayesian adaptive direct search algorithm

Genetic polymorphisms of N-acetyltransferase 2 and colorectal cancer risk

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World Journal of Gastroenterology 2005年第27期11卷 4268-4271页

作者： Lu-Jun he Yue-Ming Yu Fang Qiao Jing-shan Liu Xiao-feng Sun Ling-Ling Jiang Department of Biochemistry Hebei Medical University Shijiazhuang 050017 Hebei Province China Laboratory of HLA Hebei Province Blood Center Shijiazhuang 050071 Hebei Province China Department of Surgery No. 4 Hospital of Hebei Medical University Shijiazhuang 050011 Hebei Province China Department of Oncology Institute of Biomedicine and Surgery University of Linkǒping S-581 85 Linkǒping Sweden

AIM： To identify the distribution of N-acetyltrasferase 2 （NAT2） polymorphism in hebei Han Chinese and the effects of the polymorphism on the development of colorectal ***： We performed a hospital-based case-control study of 237 healthy individuals and 83 colorectal cancer patients of hebei Han Chinese. DNA was extracted from peripheral blood and cancer tissues. The genotypes of the polymorphisms were assessed by PCR-restriction fragment length polymorphism（RFLP）.RESULTS： There were four NAT2 alleles of WT, M1, M2,and M3 both in the healthy subjects and in the patients,and 10 genotypes of WT/WT, WT/M1, WT/M2, WT/M3,M1/M1, M1/M2, M1/M3, M2/M2, M2/M3, M3/M3. M2 allele was present in 15.61% of healthy subjects and 29.52% of patients （X^2 = 15.31, P〈0.0001）, and M3 allele was present in 30.59% of healthy subjects and 16.87% of patients （X^2 = 25.33, P〈0.0001）. There were more WT/M2 （X^2= 34.42, P〈0.0001, odd ratio= 4.99, 95%CI = 2.27-9.38）and less WT/M3 （X^2 = 3.80, P = 0.03） in the patients than in the healthy subjects. In 70.3% of the patients, there was a difference in NAT2 genotype between their tumors and blood cells. Patients had more WT/M2 （7.2 = 5.11,P = 0.02） and less M2/M3 （X^2= 4.27, P = 0.039） in their blood cells than in the tumors. Furthermore, 53.8% （7/13）of M2/M3 in tumors were from VVT/M2 of blood ***： There is a possible relationship between the NAT2 polymorphisms and colorectal cancer in hebei Han Chinese. The genotype WT/M2 may be a risk factor for colorectal cancer.

关键词： NAT2 gene Colorectal cancer RFLP

Capacity analysis of high-rank line-of-sight MIMO channels

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Journal of Systems Engineering and Electronics 2009年第4期20卷 706-710页

作者： Xiao Hailin Ouyang shan Nie Zaiping Zhao feng School of Information and Communications Guilin Univ. of Electronic Technology Guilin 541004 P. R. China School of Electronic engineering Univ. of Electronic Science and Technology of china Chengdu 610054 P. R. China

Matrix perturbation theory is utilized to investigate high-rank line of sight multiple input multiple output channels in a microwave relay system. The upper and lower bounds of channel capacity are derived based on space time block codes technique and singular values decomposition. A useful constraint for designing LOS MIMO channels is developed by the use of the condition number of the MIMO channel matrix. The theoretical analysis of channel capacity is confirmed by the simulation. The results show that the proposed method is able to give a physical explanation of the high-rank LOS MIMO channel matrix characteristics.

关键词： MIMO channel matrix perturbation theory condition number space time block code

Characteristics and Sources of Organic Matter from the Early Cambrian Niutitang Formtion and Its Preservation Environment in Guizhou

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Journal of Earth Science 2022年第4期33卷 933-944页

作者： Hong Wei Qinglai feng Jianxin Yu shan Chang State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences China University of GeosciencesWuhan 430074China College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435002China

The Early Cambrian Niutitang Formation on the Yangtze Block is a set of high-quality marine source ***,hydrocarbon-forming organisms of these organic-rich shales was poorly *** this paper,the results of palynofacies analysis and hydrocarbon-forming organism characteristics of the Niutitang Formation from the Yangtze Block are reported for the first time,and the sedimentary environment is discussed in combination with geochemical *** analysis show that the organic matter(OM)of the Niutitang Formation is mainly composed of amorphous organic matter(AOM),with a small amount of structural organic matter(STOM)and palynomorphs(PL).The results of CONISS(stratigraphically constrained incremental sum of squares)cluster analysis show that the PL can be divided into three zones in the ascending order:Leiosphaeridia-Micrhystridiumfungal zone,algal bloom zone and fungal development zone,corresponding to three stages:transgression,high-stand and regression,*** principal component analysis(PCA)shows that the main hydrocarbon-forming organisms include planktonic green microalgae or dinoflagellates that are related to Leiosphaeridia and *** analysis and geochemical data show that the Niutitang Formation was deposited under anoxic or dysoxic condition which was favorable to the enrichment of organic matter.

关键词： organic matter palynofacies hydrocarbon-forming organisms sedimentary environment Niutitang Formation Yangtze Block