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充气搅拌预处理对黄铜矿和磁黄铁矿浮选分离的影响

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矿产综合利用 2022年第5期43卷 165-168页

作者：张福亚张建辉北矿机电科技有限责任公司北京100160

为提高黄铜矿浮选中脱除磁黄铁矿的效果,本文研究了通过充气搅拌预处理的方法实现黄铜矿和磁黄铁矿的有效分离。主要考查了加药顺序、搅拌时间和充气量与黄铜矿回收率的关系。研究结果表明,先加药再充气调浆搅拌的效果要好于后先充气搅... 详细信息

为提高黄铜矿浮选中脱除磁黄铁矿的效果,本文研究了通过充气搅拌预处理的方法实现黄铜矿和磁黄铁矿的有效分离。主要考查了加药顺序、搅拌时间和充气量与黄铜矿回收率的关系。研究结果表明,先加药再充气调浆搅拌的效果要好于后先充气搅拌后加药的效果;充气量的增加有助于提高黄铜矿回收率,并且气量达到2 m3/h后回收率变化平缓;搅拌0~35 min内黄铜矿回收率随搅拌时间增加而增加,35 min时回收率达到极高,然后变化趋于平缓。以上现象可能的原因是,磁黄铁矿的氧化消耗了矿浆中的氧气,从而造成矿浆中没有足够的氧来参与黄药与黄铜矿的吸附过程。矿浆中充入空气后,空气中的氧参与了磁黄铁矿的表面氧化,从而保证了矿浆中有足够的氧来参与黄药在黄铜矿表面的吸附过程,进而提高了黄铜矿的回收率。

关键词：充气回收率矿浆吸附氧化

A novel gene signature based on five immune checkpoint genes predicts the survival of glioma

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Chinese Neurosurgical Journal 2021年第2期7卷 98-106页

作者： Wei zhang You Zhai Guanzhang Li Tao Jiang Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Molecular Neuropathology Beijing Neurosurgical InstituteCapital Medical UniversityNo.119 South Fourth Ring Road WestFengtai DistrictBeijingChina Center of Brain Tumor Beijing Institute for Brain DisordersBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Chinese Glioma Genome Atlas Network(CGGA)and Asian Glioma Genome Atlas Network(AGGA) BeijingChina

Background:Glioma is the most common and fatal type of nerve neoplasm in the central nervous *** biomarkers have been considered for prognosis prediction,which is not accurate *** aimed to carry out a gene signature related to the expression of immune checkpoints which was enough for its performance in ***:Gene expression of immune checkpoints in TGGA database was *** 5 selected genes underwent verification by COX and Lasso-COX ***,the selected genes were included to build a novel signature for further ***:Patients were sub-grouped into high and low risk according to the novel *** response,clinicopathologic characters,and survival showed significant differences between those 2 *** including“naive,”“effector,”and“IL-4”were screened out by *** results showed strong relevance between the signature and immune ***:We constructed a gene signature with 5 immune *** signature predicted survival *** novel signature performed more functional than previous biomarkers.

关键词： Glioma Immune checkpoints Gene signature Prognosis

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光伏集群逆变器的谐振机理及抑制技术研究

电网技术 2018年第10期42卷 3377-3384页

作者：万庆祝张翃帆张学哲孙健北方工业大学电气与控制工程学院北京市石景山区100144 国网北京市电力公司客户服务中心北京市东城区100062 国网北京市电力公司电力科学研究院北京市丰台区100075

光伏集群式发电能够提高光伏电站的发电效率,但是光伏集群逆变器并网后会产生谐振,影响电力系统安全稳定运行。为了保证电网供电可靠性,研究了光伏集群系统的谐振产生机理,并对谐振特性进行分析,提出了电容电流前馈与逆变器侧电流反馈... 详细信息

光伏集群式发电能够提高光伏电站的发电效率,但是光伏集群逆变器并网后会产生谐振,影响电力系统安全稳定运行。为了保证电网供电可靠性,研究了光伏集群系统的谐振产生机理,并对谐振特性进行分析,提出了电容电流前馈与逆变器侧电流反馈控制和RC型全局谐振抑制相结合的控制策略,对光伏集群系统进行谐振抑制。通过仿真和实验验证控制方法的有效性,实验结果表明谐振可以被有效抑制,光伏集群系统可以安全稳定地接入电网,保证供电可靠性。

关键词：光伏集群逆变器谐振特性全局谐振抑制

Risk factors associated with mortality of COVID-19 in 3125 counties of the United States

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Infectious Diseases of Poverty 2021年第1期10卷 98-98页

作者： Ting Tian Jingwen zhang Liyuan Hu Yukang Jiang Congyuan Duan Zhongfei Li Xueqin Wang Heping zhang 不详 School of Statistics Capital University of Economics and Business121 ZhangjialukouHuaxiang Fengtai DistrictBeijing 100070China School of Public Health Yale University60 College StreetNew HavenCT 06520-8034USA

Background:The number of cumulative confirmed cases of COVID-19 in the United States has risen sharply since March 2020.A county health ranking and roadmaps program has been established to identify factors associated with disparity in mobility and mortality of COVID-19 in all counties in the United *** risk factors associated with county-level mortality of COVID-19 with various levels of prevaIence are not well ***:Using the data obtained from the County Health Rankings and Roadmaps program,this study applied a negative binomial design to the courtty-level mortality counts of COVID-19 as of August 27,2020 in the United *** this design,the infected counties were categorized into three levels of infections using clustering analysis based on time-var ying cumulative con firmed cases from March 1 to August 27,***-19 patients were not analyzed in dividually but were aggregated at the county-level,where the coun ty-level deaths of COVID-19 con firmed by the local health *** analysis and Kruskal-Wallis tests were used in our statistical analysis.

关键词： Adverse health factors County-level confirmed and deaths Race/ethnicity Segregation index Physical environment

Epidemiology and evolution of Middle East respiratory syndrome coronavirus, 2012-2020

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Infectious Diseases of Poverty 2021年第3期10卷 1-13页

作者： An-Ran zhang Wen-Qiang Shi Kun Liu Xin-Lou Li Ming-Jin Liu Wen-Hui zhang Guo-Ping Zhao Jin-Jin Chen Xiao-Ai zhang Dong Miao Wei Ma Wei Liu Yang Yang Li-Qun Fang Department of Epidemiology School of Public HealthCheeloo College of MedicineShandong University44 West Wenhua RoadJinanPeople's Republic of China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology20 Dong-Da StreetFengtai DistrictBeijing 100071People's Republic of China Department of Biostatistics College of Public Health and Health Professionsand Emerging Pathogens InstituteUniversity of FloridaGainesvilleFLUSA Department of Epidemiology Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational EnvironmentSchool of Public HealthAir Force Medical UniversityxranPeople's Republic of China Department of Medical Research Key Laboratory of Environmental Sense Organ Stress and Health of the Ministry of Environmental ProtectionPLA Stragetic Support Force Characteristic Medical CenterBeijingPeople's Republic of China Logistics College of Chinese People's Armed Police Forces TianjinPeople's Republic of China.

Background:The ongoing transmission of the Middle East respiratory syndrome coronavirus(MERS-CoV)in the Middle East and its expansion to other regions are raising concerns of a potential *** in-depth analysis about both population and molecular epidemiology of this pathogen is ***:MERS cases reported globally as of June 2020 were collected mainly from World Health Organization official reports,supplemented by other reliable *** for case fatality and spatial diffusion of MERS were assessed with Logistic regressions and Cox proportional hazard models,*** and phylogeographic analyses were performed to examine the evolution and migration history of ***:A total of 2562 confirmed MERS cases with 150 case clusters were reported with a case fatality rate of 32.7%(95%Cl:30.9-34.6%).Saudi Arabia accounted for 83.6%of the *** of>65 years old,underlying conditions and>5 days delay in diagnosis were independent risk factors for ***,a history of animal contact was associated with a higher risk(adjusted OR=297,95%Cl:1」0-7.98)among female cases65 years *** of the disease was fastest from its origin in Saudi Arabia to the east,and was primarily driven by the transportation *** most recent subclade C5.1(since 2013)was associated with non-synonymous mutations and a higher mortality *** analyses pointed to Riyadh of Saudi Arabia and Abu Dhabi of the United Arab Emirates as the hubs for both local and international spread of ***:MERS-CoV remains primarily locally transmitted in the Middle East,with opportunistic exportation to other continents and a potential of causing transmission clusters of human *** contact is associated with a higher risk of death,but the association differs by age and *** network is the leading driver for the spatial diffu

关键词： Middle East respiratory syndrome MERS-CoV Case fatality rate Spatial diffusion Phylogeny Phylogeographic dynamic

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新技术条件下编组站运输指挥方式的探讨

铁道经济研究 2008年第6期 16-18页

作者：张振儒张磊北京铁路局丰台西站

随着铁路又好又快发展的不断深入,运输生产呈现出新的形势,迫切需要采用新技术、新设备和新的管理模式,全面提高枢纽编组站的运营管理水平,提高作业效率,加速车辆周转,缩短车辆在站停留时间,为全局运输创造良好条件。以丰台西站创建综... 详细信息

随着铁路又好又快发展的不断深入,运输生产呈现出新的形势,迫切需要采用新技术、新设备和新的管理模式,全面提高枢纽编组站的运营管理水平,提高作业效率,加速车辆周转,缩短车辆在站停留时间,为全局运输创造良好条件。以丰台西站创建综合指挥中心构想为切入点,对新技术条件下编组站运输指挥方式做进一步探讨。

关键词：编组站运输指挥调度丰台西站

生态文明建设背景下北京市城乡建设用地效率评价

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地域研究与开发 2022年第3期41卷 25-30页

作者：张潆文张浩楠王介勇北京城市学院首都城市环境建设研究基地北京100083 中国科学院地理科学与资源研究所北京100101 中国科学院大学资源与环境学院北京100049

采用数据包络分析和Malmquist指数法,对2013—2019年北京市城乡建设用地效率进行综合评价。结果表明:(1)2013—2019年,北京市各区城乡建设用地效率总体呈稳步上升态势,但仍有较大提升空间;规模报酬递减效应日益显著,规模效率呈现下降趋... 详细信息

采用数据包络分析和Malmquist指数法,对2013—2019年北京市城乡建设用地效率进行综合评价。结果表明:(1)2013—2019年,北京市各区城乡建设用地效率总体呈稳步上升态势,但仍有较大提升空间;规模报酬递减效应日益显著,规模效率呈现下降趋势。(2)各区效率水平呈明显分层结构和组团化特征,首都功能核心区(东城区、西城区)和生态涵养发展区(门头沟区、延庆区等)总体优于城市功能拓展区(丰台区等)和城市发展新区(通州区、昌平区等)。(3)效率重心位于中心城区北部,总体向东北方向移动。(4)2019年通州区、丰台区等6个低效区各类投入冗余和产出不足相对突出,需加强用地管控和存量挖潜。(5)北京市城乡建设用地全要素生产率提升主要受技术进步驱动,年均增长率为9.7%。未来,北京市应贯彻新发展理念,持续探索生态友好型、节约集约型土地利用模式,加快构建高效绿色的国土空间开发保护新格局。

关键词：城乡建设用地利用效率数据包络分析 Malmquist指数北京市

Identification of tick-borne pathogen diversity by metagenomic analysis in Haemaphysalis longicornis from Xinyang,China

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Infectious Diseases of Poverty 2018年第1期7卷 440-447页

作者： Lu Zhuang Juan Du Xiao-Ming Cui Hao Li Fang Tang Pan-He zhang Jian-Gong Hu Yi-Gang Tong Zhi-Chun Feng Wei Liu State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology20 Dong-Da StreetFengtai DistrictBeijing 100071People’s Republic of China Affiliated Bayi Children’s Hospital PLA Army General Hospital5 Nan-Men-CangDongcheng DistrictBeijing 100700People’s Republic of China National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology 5 Nan-Men-CangDongcheng DistrictBeijing 100700People’s Republic of China Center for Diseases Control and Prevention of Chinese Peoples’Armed Police Forces Beijing 102613China

Background:A wide variety of pathogens could be maintained and transmitted by Haemaphysalis *** aim of this study is to systematically examine the variety of pathogens carried by Haemaphysalis longicornis,an importnatn vector,in tick-borne diseases epidemic area,and to estimate the risk of human infection imposed by tick ***:Adult questing ticks were collected in Xinyang,central *** DNA and RNA were extracted from 144 *** ticks individually,and sequenced respectively as the templates for high-throughput *** reads were compared against the database of NCBI nucleotide collection and specific PCR was performed to confirm the presence of *** analysis was performed to explore the evolutionary status of ***:The assignment of reads to taxa based on BLASTN results revealed the existence of several potential pathogens,including Anaplasma spp.,Rickettsia spp.,Babesia sp.,as well as severe fever with thrombocytopenia syndrome bunyavirus(SFTSV).Comfirmantory PCR assays revealed the existence of Anaplasma bovis(13/144,9.03%),Anaplasma centrale(2/144,1.39%),Rickettsia heilongjiangensis(3/144,2.08%),Rickettsia ***-13(1/144,0.69%),Rickettsia raoultii(5/144,3.47%),Babesia sp.(1/144,0.69%).SFTSV accounted for the highest detected pathogen with a positive rate of 18.75%(27/144).Three of the ticks(2.08%)were co-infected with SFTSV and ***:Our study provided a broadened list of microorganism that harbored by *** previously unrecognized endemic regions,prokaryotic and eukaryotic infection including Anaplasma spp.,Rickettsiae spp.,and Babesia *** be considered,along with the well-known SFTSV for patients with tick bites history.A novel Babesia species was identified in local natural foci,which needs further investigation in the future.

关键词： Haemaphysalis longicornis Pathogens High-throughput sequencing

Immunotherapy with heat shock protein 96 to treat gliomas

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中华神经外科杂志(英文) 2021年第1期6卷 53-57页

作者： Li Chunzhao Du Yifei zhang Yang Ji Nan Department of Neurosurgery Beijing Tiantan Hospital Capital Medical University No.119 South 4th Ring West Road fengtai District Beijing 100070 China Beijing Shijitan Hospital No.10 Yangfangdian Road Beijing 100038

Heat shock protein 96 (gp96) is a highly conserved protein in the endoplasmic reticulum. The functions of gp96 include promoting the oncogenesis and progression of glioma. In addition, tumor-derived gp96 can activate anti-tumor immune. Therefore, this protein was used to generate an anti-tumor vaccine and widely applied to glioma therapy. This review summarizes the mechanisms of gp96 in glioma oncogenesis and clinical trials of the gp96 tumor vaccine in glioma treatment.

关键词： Glioma gp96 Tumor vaccine Oncogenesis