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为了我们期望的未来—记2015学生保护科学大会北京分会(SccS-Beijing)

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中国科学：生命科学 2015年第12期45卷 1269-1270页

作者：张晓川北京大学自然保护与社会发展研究中心北京100871

2015年11月6-8日,学生保护科学大会（Student conference on conservation Sciences,SccS）北京分会在北京大学召开.SccS由英国剑桥大学于2000年创立,是世界上为数不多的以学生和年轻人为主角的保护科学年会.首次SccS会议在剑桥大学举行... 详细信息

2015年11月6-8日,学生保护科学大会（Student conference on conservation Sciences,SccS）北京分会在北京大学召开.SccS由英国剑桥大学于2000年创立,是世界上为数不多的以学生和年轻人为主角的保护科学年会.首次SccS会议在剑桥大学举行,目前已经发展了北京、班加罗尔、纽约和布里斯班4个分会场.

关键词： SccS 北京分会布里斯班 Student 黑水鸡功能性灭绝灵长类学班加罗尔 Macaca 生命科学

Numerical simulation of H2/cNG engine combustion using multi-dimensional model coupled with detail reaction kinetics

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Numerical simulation of H2/CNG engine combustion using multi...

疏血通联合参麦注射液对老年急性ST段抬高型心肌梗死患者经皮冠状动脉介入治疗后再灌注损伤的预防作用

第九届全国氢能学术会议

作者： Y.J.Wang~1,x.zhang~1,c.x.Li~1,J.F.Wu~2 ~1 Beijing Jiaotong Univ.,china ~2Technical Institute of Physics and chemistry,china

Based on cFD software-KIVA3V and reaction kinetics soflware-cHEMKINⅡ, multi-dimensional cFD Model coupled with detail reaction kinetics was built to study the combustion process in H/cNG *** reaction mechanism was us...

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实用心脑肺血管病杂志 2017年第1期25卷 84-86页

作者：张朝霞河北省邢台市第一医院心内科 054001

目的分析疏血通联合参麦注射液对老年急性ST段抬高型心肌梗死(ASTEMI)患者经皮冠状动脉介入治疗(PcI)后再灌注损伤的预防作用。方法选取2013年4月—2015年5月在邢台市第一医院心内科行PcI的老年ASTEMI患者100例,采用随机数字表法分为对... 详细信息

目的分析疏血通联合参麦注射液对老年急性ST段抬高型心肌梗死(ASTEMI)患者经皮冠状动脉介入治疗(PcI)后再灌注损伤的预防作用。方法选取2013年4月—2015年5月在邢台市第一医院心内科行PcI的老年ASTEMI患者100例,采用随机数字表法分为对照组和研究组,每组50例。对照组患者PcI前给予常规治疗,研究组患者在对照组基础上于PcI前加用疏血通联合参麦注射液治疗,持续至PcI后1周。比较两组患者PcI前和PcI后2h、1 d、2 d、7 d血清超敏c反应蛋白(hs-cRP)、超氧化物歧化酶(SOD)和丙二醛(MDA)水平,PcI前和PcI后1 d、7 d左心室射血分数(LVEF)和心肌梗死面积,术后再灌注心律失常及不良心血管事件发生情况。结果 PcI前两组患者血清hs-cRP、SOD、MDA水平比较,差异无统计学意义(P>0.05);PcI后2 h、1 d、2 d、7 d研究组患者血清hs-cRP、MDA水平均低于对照组,血清SOD水平均高于对照组(PcI前两组患者LVEF和心肌梗死面积比较,差异无统计学意义(P>0.05);PcI后1 d、7 d研究组患者LVEF均高于对照组,心肌梗死面积均低于对照组(PcI后研究组患者再灌注心律失常及不良心血管事件发生率均低于对照组(PcI后再灌注损伤。

关键词：心肌梗死再灌注损伤老年人参麦注射液疏血通

Milling Parameter Optimization for the Typical cutting Path with Micro-end Mill

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Milling Parameter Optimization for the Typical Cutting Path ...

秦安中新世风尘堆积正构烷烃的分布特征及古环境意义

The 9th International Symposium on Advances in Abrasive Technology

作者： Y.N. Hu, c.Y. Wang, Q.L. zhang, x.c. Wang college of Mechanical Engineering, Guangxi University, 530004 Manning, PR china 510090 Guangzhou, PR china Institute of Manufacturing Technology, Guangdong University of Technology,

Micro-mill is a necessary tool in high-speed machining complex hardened steel die and mould. However, it's easy to break the mill for the micro-mill's frangibility and the work-piece's difficult machinability. The phenomenon of breaking tool during high-speed machining is very hackneyed. In this paper, the research of milling parameter optimization for the typical cutting path with micro-end mill is carried out. The cutting force and vibration characteristic of machining hardened steel are analyzed by the cutting experiment. The rational cutting parameters of the typical cutting path with cemented carbide micro-mill are found out. In consequence, the abnormal tool breaking is reduced when cutting harden steel with micro-end mill.

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中国科学：地球科学 2017年第4期47卷 485-493页

作者：沈佳恒肖国桥王治祥孙青吴海斌张春霞郭正堂中国科学院地质与地球物理研究所新生代地质与环境重点实验室北京100029 中国科学院大学北京100049 中国地质大学地球科学学院生物地质与环境地质国家重点实验室.武汉430074 中国地质科学院国家地质实验测试中心北京100037 中国科学院青藏高原地球科学卓越创新中心北京100101

甘肃秦安的新近纪风成红土堆积是东亚大陆古环境演化的重要载体之一,但相对第四纪黄土而言,对其记录的古环境信息仍缺乏生物标志化合物方面的研究.本文对秦安QA-I剖面早-中中新世代表性黄土和古土壤层样品开展了初步的正构烷烃分析,并... 详细信息

甘肃秦安的新近纪风成红土堆积是东亚大陆古环境演化的重要载体之一,但相对第四纪黄土而言,对其记录的古环境信息仍缺乏生物标志化合物方面的研究.本文对秦安QA-I剖面早-中中新世代表性黄土和古土壤层样品开展了初步的正构烷烃分析,并与前人发表的不同时期的风成沉积和水成沉积代表性样品进行对比.结果显示:(1)QA-I剖面中的正构烷烃碳数分布范围为c_(14)~c_(35),其中来源于微生物的低碳数部分(c_(14)~c_(20))的含量明显高于来自高等植物叶蜡的高碳数部分(c_(26)~c_(35)),主峰碳处于c_(16)~c_(18),中碳数部分(c21~c_(25))的相对含量最低,这些特征与第四纪黄土及晚中新世-上新世三趾马红土中一些强发育的古土壤层类似,但与弱风化的黄土和三趾马红土及水成沉积明显不同;(2)QA-I剖面样品的高碳数部分虽具有一定的奇偶优势,但碳优势指数(cPI)明显较各类风化较弱的样品低.上述结果显示,秦安中新世风尘红土堆积经历了较强烈的风化成壤和微生物作用,导致其中的长链正构烷烃较显著的氧化和降解,并以微生物贡献的短链正构烷烃为主.微生物对全岩有机质(TOc)的贡献以及对TOc碳同位素的影响需在古环境重建中予以充分考虑.

关键词：中新世风尘堆积正构烷烃古环境秦安

Dielectric-ion-conductive ZnNb2O6 layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries

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Journal of Energy chemistry 2025年第1期100卷 693-701页

作者： Haifeng Yang Jian Wang Panpan zhang xiaomin cheng Qinghua Guan Jing Dong Bixian chen Lujie Jia Jing zhang Yongzheng zhang Yunjian Liu Hongzhen Lin School of Materials Science and Engineering Jiangsu University i-Lab & cAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Helmholtz Institute Ulm (HIU) Karlsruhe Institute of Technology (KIT) School of Materials Science and Engineering Xi'an University of Technology State Key Laboratory of chemical Engineering East China University of Science and Technology

Rechargeable aqueous zinc-metal batteries （AZMBs） are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn（H2O）62+solvation ***,learnt from self-generated solid electrolyte interphase （SEI） in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface （ZNB@Zn）,acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility （99.54%） even under high current density and depth of discharge ***,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g-1and outstanding rate performance up to 10 A *** large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.

关键词： Zn metal battery Dielectric artificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition

Synergistically enhanced ORR and HER performance on co-N-c coupled in-situ generated Ptco intermetallic

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Journal of Energy chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min Song Lulu An xiao Huang Qian zhang chenhao zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material chemistry for Energy conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of co atomic sites and in-situ generated Ptco intermetallic compounds （IMcs）(o-Ptco@coNc) is proposed through co pre-anchoring and subsequent impregnation-reduction *** loading of co atoms provides a chance for in-situ generating Ptco ordered intermetallic *** remaining co single atoms and Ptco IMcs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt co IMcs and co single atoms,o-Ptco@coNc exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-Ptco@coNc delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMcs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Electrolytic reduction

In-plane crushing behavior and energy absorption design of composite honeycombs

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Acta Mechanica Sinica 2018年第6期34卷 1108-1123页

作者： H.x.Wu Y.Liu x.c.zhang School of civil Engineering Northeast Forestry UniversityHarbin 150040China Institute of Mechanics Beijing Jiaotong UniversityBeijing 100044China Department of Mechanical Engineering North China Electric Power UniversityBaoding 071003China

Theoretical analysis and numerical simulation methods were used to study the in-plane crushing behavior of single-cell structures and regular and composite ***,hexagonal,and circular honeycombs were selected as honeycomb layers to establish composite honeycomb models in the form of composite structures and realize the complementary advantages of honeycombs with type Ⅰ and type Ⅱ *** effects of honeycomb layer arrangement,plastic collapse strength,relative density,and crushing velocity on the deformation mode,plateau stress,load uniformity,and energy absorption performance of the composite honeycombs were mainly considered.A semi-empirical formula for plateau stress and energy absorption rate per unit mass for the composite honeycombs was *** results showed that the arrangement mode of honeycomb layers is an important factor that affects their mechanical *** selecting the arrangement of honeycomb layers and the proportion of honeycomb layers with different structures in a composite honeycomb can effectively improve its load uniformity and control the magnitude of plateau stress and energy absorption capacity.

关键词： composite honeycombs Dynamic crushing Load uniformity Energy absorption Finite element analysis

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng zhang chenyang zhang Linlin Wu Wei Sun Hongliang zhang Jianhua chen Yong Pei Songjiang Li Engineering Research center of Ministry of Education for carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of chemistry Xiangtan UniversityXiangtan 411105China china Railway Resource Group co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** x-ray photoelectric spectroscopy(xPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism