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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 687-692页

作者： Zhang-lin chen Kai Liu Xuan-yi Yuan ke-xin chen Beijing key Laboratory of Optoelectronic Functional Materials&Micro-nano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China State key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100872China

Nitrogen-rich Eu2+-doped Ca-α-SiAlON phosphors(Cam/2-xSi12-m-nAlm+nOnN16-n:xEu) were synthesized by a freeze-drying assisted combustion synthesis(CS) route. Fast-synthesized products with high purity and uniform particle morphology were confirmed by X-ray diffraction(XRD) and scanning electron microscopy(SEM). The analysis of lattice parameters by comparison with empirical equations showed that the as-prepared phosphors had low oxygen content. A series of samples were prepared according to the stoichiometry of Cam/2-0.08Si12-mAlmN16:0.08 Eu for further research. The influences of m value on the luminescence properties were investigated in detail. As m increased, a redshift phenomenon was observed in both the excitation and emission spectra. First-principle electronic structure calculations showed that the 3d energy level of Ca played an important role in the occurrence of the redshift phenomenon.

关键词： freeze-drying combustion synthesis phosphors powder fluorescence spectra first-principle calculation

High sensitivity C-reactive protein and cardfiac resynchronization therapy in patients with advanced heart failure

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Journal of Geriatric Cardiology 2014年第4期11卷 296-302页

作者： Chi CAI Wei HUA Li-Gang DING Jing WANG ke-Ping chen xin-Wei YANG Zhi-Min LIU Shu ZHANG Cardiac Arrhythmia Center Fuwai Hospital Beilishi road No. 167 Xicheng district Beijing 100037 China

Background The data on the prognostic values of high sensitivity C-reactive protein （hsCRP） levels in patients with advanced symp-tomatic heart failure （HF） receiving cardiac resynchronization therapy （CRT） are scarce. The aim of present study was to investigate the association of serum hsCRP levels with left ventricle reverse remodeling after six months of CRT as well as long-term outcome. Methods A total of 232 CRT patients were included. The assessment of hsCRP values, clinical status and echocardiographic data were performed at baseline and after six months of CRT. Long-term follow-up included all-cause mortality and hospitalizations for HF. Results During the mean follow-up periods of 31.3 ± 31.5 months, elevated hsCRP （〉3 mg/L） prior to CRT was associated with a significant 2.39-fold increase （P=0.006） in the risk of death or HF hospitalizations. At 6-month follow-up, patients who responded to CRT showed significant reductions or maintained low in hsCRP levels （–0.5 ± 4.1 mg/L reduction） compared with non-responders （1.7 ± 6.1 mg/L increase, P=0.018）. Com-pared with patients in whom 6-month hsCRP levels were reduced or remained low, patients in whom 6-month hsCRP levels were increased or maintained high experienced a significantly higher risk of subsequent death or HF hospitalizations （Log-rank P〈0.001）. The echocardio-graphic improvement was also better among patients in whom 6-month hsCRP levels were reduced or remained low compared to those in whom 6-month hsCRP levels were raised or maintained high. Conclusions Our findings demonstrated that measurement of baseline and follow-up hsCRP levels may be useful as prognostic markers for timely potential risk stratification and subsequent appropriate treatment strategies in patients with advanced HF undergoing CRT.

关键词： Cardiac resynchronization therapy Clinical outcome Heart failure High sensitivity C-reactive protein

Pouch size influences clinical outcome of pouch construction after total gastrectomy:A meta-analysis

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World Journal of Gastroenterology 2014年第29期20卷 10166-10173页

作者： Heng-Lei Dong Yu-Bei Huang Xue-Wei Ding Feng-Ju Song ke-xin chen Xi-Shan Hao Department of Epidemiology and Biostatistics Tianjin Medical University Cancer Hospital and InstituteNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and Therapy Department of Gastric Cancer Surgery Tianjin Medical University Cancer Hospital and InstituteNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and Therapy

AIM: To assess the clinical significance of pouch size in total gastrectomy for gastric malignancies.

关键词： Total gastrectomy Gastric cancer Pouch size Systematic review

Influence of wettability in immiscible displacements with lattice Boltzmann method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第9期23卷 704-720页

作者： chen ZHOU Wen-yuan WANG ke-xin chen Ze-jian chen Jongwon JUNG Shuai ZHANG Yun-min chen Bate BATE Institute of Geotechnical Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina School of Civil Engineering Chungbuk National UniversityCheongjuChungbuk 28644Korea

The role of wettability,often characterized by contact angle(θ),in two-phase immiscible phases displacement is not well *** this study,the color gradient lattice Boltzmann method(LBM),capable of maintaining the prescribedθ(from 0°to 180°at intervals of 10°)throughout the numerical simulations,was used to investigate the displacement patterns and displacement efficiency in a 2D porous *** capillary numbers(Ca)used were 0.01,1,and 100,and the viscosity ratios(M)used were 0.1,1,and *** M=10,the saturation(S)had a bilinear relationship withθ,while for M=0.1 and 1,the S-θrelationships were complicated by Ca.A saturation contour in the M-Ca-θspace was proposed to demonstrate the movement of a traditional 2D M-Ca phase diagram withθ*** value of S continued to increase after the breakthrough,and the final saturation(0.997)for the hydrophilic condition(θ=10°)was higher than that(0.673)for the hydrophobic condition(θ=170°).

关键词： Wettability Porous media Lattice Boltzmann method(LBM) Multiphase flow

Short-term effect of cardiac resynchronization therapy in patients with ischaemic or nonischaemic cardiomyopathy

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Chinese Medical Journal 2006年第18期119卷 1507-1510页

作者： HUA Wei NIU Hong-xia WANG Fang-zheng ZHANG Shu chen ke-ping chen xin Department of Clinical Electrophysiology Fuwai Hospital and Cardiovascular Institute Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100037 China

Background Patients with heart failure were candidates for cardiac resynchronization therapy （CRT） regardless of underlying aetiology. This study observed the effect of CRT in patients with ischaemic or nonischaemic cardiomyopathy. Methods One hundred and forty-two patients with refractory chronic heart failure and left bundle branch block received cardiac resynchronization therapy, 91 men and 51 women, average age 60 years. Left ventricular ejection fraction （LVEF） was severely depressed （mean 29%）, left ventricular end diastolic diameter （LVEDD） enlarged （mean 72 mm） and QRS width was lengthened （mean 147 ms）. Ninety-eight had nonischaemic cardiomyopathy and 44 had ischaemic cardiomyopathy. Results After cardiac resynchronization therapy, the heart function was significantly improved. The mean LVEF increased from 29% to 36% after pacing. In patients with nonischaemic cardiomyopathy, the LVEF was improved from 28% to 37%, and in patients with ischaemic cardiomyopathy, the LVEF was improved from 30% to 36%. No significant difference of the improvement was found between the two groups （P〉0.05）. Conclusions Cardiac resynchronization therapy could significantly improve cardiac function in patients with chronic heart failure regardless of the underlying heart disease.

关键词： cardiac resynchronization therapy cardiomyopathy, ischaemic nonischaemic

Complications of cardiac resynchronization therapy in patients with congestive heart failure

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Chinese Medical Journal 2006年第6期119卷 449-453页

作者： NIU Hong-xia HUA Wei WANG Fang-zheng ZHANG Shu chen ke-ping chen xin Centre of Arrhythmia Diagnosis and Treatment Fuwai HospitalChinese Academy of Medical Sciences and Peking Union MedicalCollege Beijing 100037 China

Background Previous clinical studies have suggested that patients with congestive heart failure and intraventricular conduction delay could benefit from cardiac resynchronization therapy （CRT）. Implantation of left ventricular lead is a complex procedure with some potential for complications. This study was conducted to analyse the complications of CRT in patients with congestive heart failure.Methods Totally 117 patients, 86 males and 31 females, mean age of 53 years, with congestive heart failure and intraventricular conduction delaywere enrolled in this study. Venography was performed on all patients. Different types of coronary sinus leads were used to pace the left ventricle.Results Left ventricular lead was attempted to implant through coronary sinus for all the 117 patients and was successfully implanted in 111 patients. The success rate was 94.9%. Main complications rate was 6.8%, including coronary sinus dissection in 4 patients, phrenic nerve stimulation required lead repositioning in 2 patients and lead dislodgement in 2 patients.Conclusions It is feasible and safe to pace left ventricle through coronary sinus. However, there are some procedural complications.

关键词： cardiac resynchronization therapy congestive heart failure compfication

A bird's eye view of the air pollution-cancer link in China

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Chinese Journal of Cancer 2014年第4期33卷 176-188页

作者： Yu-Bei Huang Feng-Ju Song Qun Liu Wei-Qin Li Wei Zhang ke-xin chen Department of Epidemiology and Biostatistics Tianjin Medical University Cancer Institute and Hospital Department of Neurosurgery Tianjin Medical University Cancer Institute and Hospital Project Office Tianjin Women's and Children's Health Center Department of Pathology The University of Texas MD Anderson Cancer Center

Air pollution in China comes from multiple sources,including coal consumption,construction and industrial dust,and vehicle *** consumption in particular directly determines the emissions of three major air pollutants:dust,sulfur dioxide(SO2),and nitrogen oxide(NOx).The rapidly increasing number of civilian vehicles is expected to bring NOx emission to a very high *** to expectations,however,existing data show that the concentrations of major pollutants[particulate matter-10(PM10),SO2,and nitrogen dioxide(NO2)]in several large Chinese cities have declined during the past decades,though they still exceed the national standards of ambient air *** data from China does not fully support that the concentrations of pollutants directly depend on local emissions,but this is likely due to inaccurate measurement of *** on the cancer registry data show that cancer burden related to air pollution is on the rise in China and will likely increase further,but there is a lack of data to accurately predict the cancer *** experience from other countries has sounded alarm of the link between air pollution and *** quantitative association requires dedicated research as well as establishment of needed monitoring infrastructures and cancer *** air pollution-cancer link is a serious public health issue that needs urgent investigation.

关键词：空气污染物中国城市癌症链接鸟瞰图 NOx排放环境空气质量公共卫生问题

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N掺杂钛酸盐的电子结构和磁性研究

物理学报 2011年第12期60卷 453-459页

作者：谭兴毅陈长乐金克新陈鹏西北工业大学凝聚态结构与性质陕西省重点实验室西安710129

基于密度泛函理论,从头计算了N掺杂立方结构钛酸盐的电子结构和磁学性质.结果表明,N掺杂钛酸盐在自旋极化状态下的总能量比自旋非极化状态下的总能量小,说明N掺杂钛酸盐的基态具有铁磁性.从态密度和自旋密度分析可知,其磁性源于掺杂的N2... 详细信息

基于密度泛函理论,从头计算了N掺杂立方结构钛酸盐的电子结构和磁学性质.结果表明,N掺杂钛酸盐在自旋极化状态下的总能量比自旋非极化状态下的总能量小,说明N掺杂钛酸盐的基态具有铁磁性.从态密度和自旋密度分析可知,其磁性源于掺杂的N2p电子和价带顶O2p电子间的p-p耦合作用.

关键词：钛酸盐电子结构磁学性质

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川滇地区井水位潮汐响应特性分析

地震 2017年第1期37卷 20-30页

作者：巩浩波李光科廖欣陈敏重庆市地震局重庆401147 防灾科技学院河北三河065201

利用Baytap-G潮汐分析软件对川滇地区12口观测井数字化水位的长时序数据进行计算,提取井水位潮汐响应特征参数(振幅比和相位差),分析其形态、阶段变化等特征,探讨地震前后井水位潮汐响应特征参数的变化情况,为深入分析井水位与固体潮、... 详细信息

利用Baytap-G潮汐分析软件对川滇地区12口观测井数字化水位的长时序数据进行计算,提取井水位潮汐响应特征参数(振幅比和相位差),分析其形态、阶段变化等特征,探讨地震前后井水位潮汐响应特征参数的变化情况,为深入分析井水位与固体潮、气压之间响应关系的研究提供新的方法和途径。结果表明,泸沽湖井等10口受固体潮影响的井水位振幅比和相位差变化相对稳定;而南溪井和大姚井受到气压-固体潮综合作用影响的井水位振幅比和相位差变化则比较离散。其中江油川10井、泸沽湖井、东川井等3口井水位振幅比和相位差对大震的响应显著,并给出了地震能量密度与这三口井水位M2波相位差和振幅比的变化关系。

关键词：井水位潮汐响应川滇地区

城市有机垃圾处理过程中主要生理群的微生物研究

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太阳能学报 1989年第3期10卷 247-254页

作者：万波廖银章李安明刘克鑫中国科学院成都生物研究所

分别采用直接厌氧和先好氧后厌氧方法处理城市有机垃圾,并以稀释法和相应的培养基,用最大可能数量(MPN)法计算发酵过程中主要微生物生理群的数量变化。结果表明:在直接厌氧发酵过程中挥发性有机酸大量积累,最高浓度达35765PPM,日平均产... 详细信息

分别采用直接厌氧和先好氧后厌氧方法处理城市有机垃圾,并以稀释法和相应的培养基,用最大可能数量(MPN)法计算发酵过程中主要微生物生理群的数量变化。结果表明:在直接厌氧发酵过程中挥发性有机酸大量积累,最高浓度达35765PPM,日平均产气量只有25.15ml,一般厌氧异养细菌、氨化细菌、产氢产酸细菌比先好氧后厌氧法高,产甲烷细菌比先好氧后厌氧法低210倍。在先好氧后厌氧发酵过程中,在好氧末期挥发酸浓度达9160PPM,在厌氧阶段,挥发酸中的乙酸、丁酸逐渐下降,而丙酸在发酵的前7天有所上升,日平均产气量为169ml;在厌氧阶段,氨化细菌、硝酸盐还原菌、硫酸盐还原菌、产氢产酸细菌有缓慢下降趋势,产甲烷细菌在发酵 14天后才开始下降,纤维素分解菌呈缓慢上升趋势。用先好氧后厌氧方法处理城市有机垃圾能防止挥发性有机酸的大量积累,使厌氧发酵启动加快,可提高产气率,缩短发酵周期。

关键词：城市有机垃圾处理生理群微生物