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System integration of China's first PEMFC locomotive

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Journal of Modern Transportation 2013年第3期21卷 163-168页

作者： WeiRong Chen Fei Peng Zhixiang liu Qi li chaohua Dai School of Electrical Engineering Southwest Jiaotong University

In the face of growing environmental pollution, developing a fuel-cell-driven shunting locomotive is a great challenge in China for environmental protection and energy saving, which combines the environmental advantages of an electric locomotive with the lower infrastructure costs of a diesel-electric locomotive. In this paper, the investigation status and the development trend of the fuel-cell-driven shunting locomotive were introduced. Through innovation of the power system using fuel cells, an experiment prototype of a fuel-cell shunting locomotive was developed, which would reduce the effects on the environment of the existing locomotives. This was the first locomotive to use a proton exchange membrane fuel-cell （PEMFC） power plant in China. From October 2012, we started to test the fuel-cell power plant and further test runs on the test rail-line in Chengdu, Sichuan. The achieved encouraging results can provide fundamental data for the modification of the current individual fuel cell locomotives or further development of the fuel-cell hybrid ones in China.

关键词： Proton exchange membrane fuel cell ~Locomotive transportation - Hydrogen storage ~ Permanentmagnet synchronous motor

Cu_(2−x)S derived copper nanoparticles:A platform for unraveling the role of surface reconstruction in efficient electrocatalytic CO_(2)-to-C_(2)H_(4)conversion

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Nano Research 2023年第4期16卷 4494-4498页

作者： chaohua He Delong Duan Jingxiang Low Yu Bai Yawen Jiang Xinyu Wang Shuangming Chen Ran Long li Song Yujie Xiong Hefei National Laboratory for Physical Sciences at the Microscale Frontiers Science Center for Planetary Exploration and Emerging TechnologiesSchool of Chemistry and Materials Scienceand National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Hefei Comprehensive National Science Center 350 Shushanhu Rd.Hefei 230031China

Cu-based electrocatalysts have provoked much attention for their high activity and selectivity in carbon dioxide(CO_(2))conversion into multi-carbon ***,during the electrochemical reaction,Cu catalysts inevitably undergo surface reconstruction whose impact on CO_(2)conversion performance remains *** we report that polycrystalline Cu nanoparticles(denoted as Cu-s)with rich high-index facets,derived from Cu_(2−x)S through desulphurization and surface reconstruction,offer an excellent platform for investigating the role of surface reconstruction in electrocatalytic CO_(2)*** the formation of Cu-s catalyst,the two stages of desulphurization and surface reconstruction can be clearly resolved by in situ X-ray absorption spectroscopy and OH−adsorption characterizations,which are well correlated with the changes in electrocatalytic *** turns out that the high CO_(2)conversion performance,achieved by the Cu-s catalyst(Faradic efficiency of 68.6%and partial current density of 40.8 mA/cm^(2)in H-cell toward C_(2)H_(4)production),is attributed to the increased percentage of high-index facets in Cu-s during the surface ***,the operando electrochemical Raman spectroscopy further reveals that the conversion of the CO_(2)into the C_(2)H_(4)on Cu-s is intermediated by the production of**** findings manifest that the surface reconstruction is an effective method for tuning the reaction intermediate of the CO_(2)conversion toward high-value multicarbon(C2+)chemicals,and highlight the significance of in situ characterizations in enhancing the understanding of the surface structure and its role in electrocatalysis.

关键词： CO_(2)electroreduction reaction surface reconstruction high-index facets ethylene(C_(2)H_(4)) Cu catalysts

应用竞争风险模型探索影响慢性阻塞性肺疾病营养不良因素的分析

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临床肺科杂志 2024年第2期29卷 201-206,211页

作者：李意云蒋樟健杨杰华郭敏杨超华梧州市红十字会医院呼吸与危重症医学科广西梧州543002

目的采用竞争风险模型探索影响慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)营养不良的因素。方法回顾性分析梧州市红十字会医院呼吸与危重症医学科2021年1月至2022年12月收治的271例COPD患者的临床资料。通过竞争风... 详细信息

目的采用竞争风险模型探索影响慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)营养不良的因素。方法回顾性分析梧州市红十字会医院呼吸与危重症医学科2021年1月至2022年12月收治的271例COPD患者的临床资料。通过竞争风险模型评估营养不良的影响因素和发生风险,同时与Kaplan-Meier法(K-M)和Cox回归模型进行比较。根据多因素分析结果绘制列线图预测患者营养不良发生率,根据受试者工作特征曲线下面积(AUC)评价模型预测能力。结果中位随访334天,期间87例(32.10%)发生营养不良。Cox回归和竞争风险单因素分析显示,总蛋白、前白蛋白、血红蛋白、球蛋白、白蛋白/球蛋白比值、红细胞计数、白细胞计数、血氯和血钾与营养不良的发生相关。多因素竞争风险分析显示,总蛋白<63.7g/L、前白蛋白<17.4mg/dL和白蛋白/球蛋白比值<1.5是COPD患者发生营养不良的高危因素。K-M计算营养不良累积发生率(cumulative incidence function,CIF)为33.92%,竞争风险分析得到的CIF为32.10%。竞争风险模型的AUC为85.3%。结论在充分考虑竞争风险的情况下,总蛋白、前白蛋白、白蛋白/球蛋白比值越低,COPD患者发生营养不良的风险越高。与K-M和Cox回归相比,竞争风险模型能够更准确地评估COPD患者发生营养不良的风险因素和发生率,同时具有良好的预测价值,以此为依据的列线图有助于临床医生评估风险高的患者并制定个体化干预措施。

关键词：慢性阻塞性肺疾病营养不良竞争风险模型列线图

Selenium deficiency induces spleen pathological changes in pigs by decreasing selenoprotein expression,evoking oxidative stress,and activating inflammation and apoptosis

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Journal of Animal Science and Biotechnology 2021年第4期12卷 1517-1529页

作者： Shuang li Wenjuan Sun Kai Zhang Jiawei Zhu Xueting Jia Xiaoqing Guo Qingyu Zhao chaohua Tang Jingdong Yin Junmin Zhang State Key Laboratory of Animal Nutrition Institute of Animal Sciences of Chinese Academy of Agricultural SciencesBeijing 100193China State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Scientific Observing and Experiment Station of Animal Genetic Resources and Nutrition in North China of Ministry of Agriculture and Rural Affairs Institute of Animal Sciences of Chinese Academy of Agricultural SciencesBeijing 100193China

Background:The immune system is one aspect of health that is affected by dietary selenium(Se)levels and selenoprotein *** is an important immune organ of the body,which is directly involved in cellular ***,there are limited reports on Se levels and spleen ***,this study established a Se-deficient pig model to investigate the mechanism of Se deficiency-induced splenic ***:Twenty-four pure line castrated male Yorkshire pigs(45 days old,12.50±1.32 kg,12 full-sibling pairs)were divided into two equal groups and fed Se-deficient diet(0.007 mg Se/kg)or Se-adequate diet(0.3 mg Se/kg)for 16 *** the end of the trial,blood and spleen were collected to assay for erythroid parameters,the osmotic fragility of erythrocytes,the spleen index,histology,terminal deoxynucleotidyl transferase nick-end labeling(TUNEL)staining,Se concentrations,the selenogenome,redox status,and signaling related inflammation and ***:Dietary Se deficiency decreased the erythroid parameters and increased the number of osmotically fragile erythrocytes(Plin and eosin and TUNEL staining indicated that the white pulp decreased,the red pulp increased,and splenocyte apoptosis occurred in the Se deficient *** deficiency decreased the Se concentration and selenoprotein expression in the spleen(P<0.05),blocked the glutathione and thioredoxin antioxidant systems,and led to redox *** deficiency activated the NF-κB and HIF-1αtranscription factors,thus increasing pro-inflammatory cytokines(IL-1β,IL-6,IL-8,IL-17,and TNF-α),decreasing anti-inflammatory cytokines(IL-10,IL-13,and TGF-β)and increasing expression of the downstream genes COX-2 and iNOS(P<0.05),which in turn induced *** addition,Se-deficiency induced apoptosis through the mitochondrial pathway,upregulated apoptotic genes(Caspase3,Caspase8,and Bak),and downregulated antiapoptotic genes(Bcl-2)(P<0.05)at the mRNA

关键词： Apoptosis Inflammation Oxidative stress Pigs Selenium deficiency Spleen

A specific assay for JmjC domain-containing lysine demethylase and its application to inhibitor screening

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Science China(life Sciences) 2019年第10期62卷 1404-1408页

作者： He Wen Guo li Yongcan Chen Meiting li Yafei Lv Zhiming li Yinglu li Tianyun Hou Hui Wang chaohua liu Xiaopeng Lu Qian Zhu Yantao Bao Ge liu Xiaofan li Wei-Guo Zhu Guangdong Key Laboratory for Genome Stability and Human Disease Prevention Carson Cancer Research CenterDepartment of Biochemistry and Molecular BiologyShenzhen University Health Science CenterShenzhen 518060China College of life Sciences and Oceanography Shenzhen Key Laboratory of Marine Bioresource and Eco-environmental ScienceShenzhen Key Laboratory of Microbial Genetic EngineeringShenzhen UniversityShenzhen 518060China Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Beijing Key Laboratory of Protein Posttranslational Modifications and Cell FunctionDepartment of Biochemistry and Molecular BiologySchool of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China

Dear Editor, Chromatin is the macromolecular complex of DNA and histone proteins, which provides the scaffold for the packaging of our entire genome. In the basic unit of chromatin, the nucleosomes contain 147 base pairs of DNA, which is wrapped around a histone octamer, with two each of histones H2A, H2B, H3, and H4. Several types of post-translational modifications, including acetylation, phosphorylation, ubiquitination, and methylation, are possible on the tails of histones (Zhang et al., 2015). Combinations of these modifications determine the chromatin structure and transcriptional regulation of genes. Histone methylation is highlighted because of the specific dynamics related to gene regulation. Aberrant histone methylation has been observed in many types of tumors (Albert and Helin, 2010) and may contribute to the neoplastic transformation of cells (Chi et al., 2010). Histone lysine methylation is regulated by two classes of enzymes that have opposing activities: histone lysine methyltransferases (KMTs) and histone lysine demethylases (KDMs). To date, a number of mammalian KDMs have been discovered (Kooistra and Helin, 2012), and they have been separated into two classes: flavin adenine dinucleotide dependent oxidases, which were first discovered in 2004 (Shi et al., 2004), and Jumonji-C (JmjC) domain-containing enzymes, first identified in 2006 (Tsukada et al., 2006).

关键词： pairs of contribute to neoplastic transformation

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突发性强对流天气快速识别预警改进方法

高原山地气象研究 2020年第3期40卷 10-17页

作者：李朝华王磊衡志炜河北省石家庄市气象局石家庄050081 中国气象局成都高原气象研究所/高原与盆地暴雨旱涝灾害四川省重点实验室成都610072

传统多普勒天气雷达强对流灾害性天气监测采用固定阈值判别法给出强风暴的冰雹闪电灾害预警结果,该方法不适用于不同经纬度、季节和复杂地形条件下的强对流天气识别预警。本文利用循环递归的区域生长法对TITAN算法进行改进,从而快速识... 详细信息

传统多普勒天气雷达强对流灾害性天气监测采用固定阈值判别法给出强风暴的冰雹闪电灾害预警结果,该方法不适用于不同经纬度、季节和复杂地形条件下的强对流天气识别预警。本文利用循环递归的区域生长法对TITAN算法进行改进,从而快速识别三维强风暴单体及其雷达特征物理量;使用多普勒天气雷达和TRMM星载气象雷达的历史观测数据反演河北石家庄地区春夏两季复杂地形条件下的强风暴灾害性天气Logistics多元线性回归概率预警模型。对发生在河北石家庄夏季的一次强飑线天气和发生在春季的一次超级多单体风暴天气进行冰雹闪电灾害性天气识别预警实验,并与传统算法进行误差对比分析。实验结果表明:与传统算法对比,该方法对强风暴天气识别预警的定位精度较高,并且其漏报率和虚报率较低,有助于快速识别预警强对流灾害性天气。

关键词：雷暴天气预警多普勒天气雷达 Logistics概率模型区域生长法

荣昌猪、约荣猪和杜长大三元猪肉色与肌红蛋白相关性研究

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中国畜牧兽医 2024年第5期51卷 1958-1968页

作者：杨培萱胡颖冯潇慧杨飞云周晓容黄金秀李敬汤超华秦玉昌张军民中国农业科学院北京畜牧兽医研究所畜禽营养与饲养全国重点实验室北京100193 重庆市畜牧科学院重庆408599 郑州大学农学院郑州450001

【目的】探究荣昌猪、大约克夏猪×荣昌猪(约荣猪)与杜洛克猪×长白猪×大白猪(杜长大三元猪)的肉色和肉中肌红蛋白含量差异,验证肉色与肌红蛋白的相关性,为商品猪肉色评价提供基础数据。【方法】采集荣昌猪(n=15)、约荣猪(n=20)、杜长... 详细信息

【目的】探究荣昌猪、大约克夏猪×荣昌猪(约荣猪)与杜洛克猪×长白猪×大白猪(杜长大三元猪)的肉色和肉中肌红蛋白含量差异,验证肉色与肌红蛋白的相关性,为商品猪肉色评价提供基础数据。【方法】采集荣昌猪(n=15)、约荣猪(n=20)、杜长大三元猪(n=20)背最长肌肉样,结合肉色度值、可见吸收光谱及公式对宰后45 min、6 h、12 h和24 h荣昌猪、约荣猪、杜长大三元猪的肉色和肌红蛋白含量分别进行测算,并探究猪肉色和肌红蛋白的关联性。【结果】荣昌猪肉红度值显著高于杜长大三元猪(P约荣猪>杜长大三元猪。宰后45 min,荣昌猪肉中总肌红蛋白含量显著高于约荣猪和杜长大三元猪(P<0.05),氧合肌红蛋白含量显著高于杜长大三元猪(P<0.05),高铁肌红蛋白相对含量显著低于约荣猪和杜长大三元猪(P<0.05)。宰后24 h,荣昌猪肉中高铁肌红蛋白含量及氧合肌红蛋白、高铁肌红蛋白相对含量均显著高于45 min和6 h(P<0.05)。相关性分析显示,红度值、总肌红蛋白和氧合肌红蛋白含量之间存在显著高度正相关(P<0.05)。【结论】荣昌猪肉因红度值高、总肌红蛋白含量高和高铁肌红蛋白相对含量低而肉色更鲜红,猪肉色优劣与肌红蛋白含量及其氧化还原状态密切相关。

关键词：荣昌猪约荣猪杜长大三元猪肉色肌红蛋白

Two-step phase manipulation by tailoring chemical bonds results in high-performance GeSe thermoelectrics

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The Innovation 2023年第6期4卷 59-68页

作者： Wenqing Yao Yihua Zhang Tu Lyu Weibo Huang Nuoxian Huang Xiang li chaohua Zhang Fusheng liu Matthias Wuttig Yuan Yu Min Hong lipeng Hu College of Materials Science and Engineering Shenzhen UniversityShenzhen 518060China Institute of Physics(A) RWTH Aachen UniversitySommerfeldstraBe 1452074 AachenGermany PGI 10(Green IT) Forschungszentrum Jjilich GmbH52428 JdlichGermany Center for Future Materials and School of Engineering University of Southem QueenslandSpringfield CentralQLD 4300Australia

In thermoelectrics,phase engineering serves a crucial function in deter-mining the power factor by affecting the band ***,for low-symmetry compounds,the mainstream one-step phase manipulation strategy,depending solely on the valley or orbital degeneracy,is inadequate to attain a high density-of-states effective mass and exceptional ***,we employ a distinctive two-step phase manipulation strategy through stepwise tailoring chemical bonds in ***,we amplify the valley degeneracy via CdTe alloying,which elevates the crystal symmetry from a covalently bonded orthorhombic to a metavalently bonded rhombohedral phase by significantly suppressing the Peierls ***,we incorporate Pb to trigger the convergence of multivalence bands and further enhance the density-of-states effective mass by moderately restraining the Peierls ***,the atypical metavalent bonding in rhombohedral GeSe enables a high Ge vacancy concentration and a small band effective mass,leading to increased carrier concentration and *** weak chemical bond along with strong lattice anharmonicity also reduces lattice thermal ***,this unique property ensemble contributes to an outstanding zT of 0.9 at 773 K for Geo.8oPbo.2oSe(CdTe)*** work underscores the pivotal role of the two-step phase manipulation by stepwise tailoring of chemical bonds in improving the thermoelectric performance of p-bonded chalcogenides.

关键词： alloying phase chemical

有缆式第四代智能分层注水技术优化及现场应用

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粘接 2024年第7期51卷 117-120页

作者：袁永文张西峰李宏伟胡春宁朝华杨红刚程严军中国石油青海油田公司钻采工艺研究院甘肃敦煌736200 中国石油青海油田公司采油五厂青海花土沟816499

青海油田注水开发油藏类型多,非均值性强,开发矛盾突出,在精细注水实施过程中测调工作量和测试力量不足,由于井况条件产生的测试遇阻问题也未能有效解决。为此油田引进第四代分层注水工艺,不需要投捞测试仪器,解决了仪器遇阻、遇卡的问... 详细信息

青海油田注水开发油藏类型多,非均值性强,开发矛盾突出,在精细注水实施过程中测调工作量和测试力量不足,由于井况条件产生的测试遇阻问题也未能有效解决。为此油田引进第四代分层注水工艺,不需要投捞测试仪器,解决了仪器遇阻、遇卡的问题,优化电缆密封方式、研制电缆直穿式封隔器和远程通信及控制技术,实现了对注水层段在实时在线调控,为油田开发提供了技术支撑,为后续工艺升级提供了基础。有缆式智能分注技术在青海油田实施45口井,最大分注级数为5封5配,最大下深2033.5 m,施工层段密封率达到100%,单井调配时间相比桥式偏心提高了6倍,测试成功率达到100%。

关键词：青海油田分层注水关键技术工艺优化