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Journal of Materials Science & Technology 2024年第1期168卷 208-214页

作者： Huimin zhang Yachao Wang Zuhair A.Munir yongzhong zhang Wenhao Fan Shaoping Chen College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Capital Aerospace Machinery Company Beijing100076China Department of Material Science and Engineering University of CaliforniaDavisCalifornia95616United States of America College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan030024China Instrumental Analysis Center of Taiyuan University of Technology Taiyuan030024China

Mg_(3)Sb_(2)-based thermoelectric materials have been the focus of widespread investigations as promising candidates for the harvesting of waste *** stability and service performance are key points for the commercial applications of these *** utilized Mg_(4.3)Sb_(3)Ni as a barrier layer to improve the thermal stability of Mg 3 Sb 2-based ***,its intrinsic high resistivity contributed nega-tively to the desired performance of the *** this work,we investigated two other Mg-Sb-Ni ternary phases,MgSbNi and MgSbNi_(2),as new barrier layer materials to connect with Mg_(3.2)Sb_(2)Y_(0.05).The results show that the efficiency of the Mg_(1.2)SbNi/Mg_(3.2)Sb_(2)Y_(0.05)/Mg_(1.2)SbNi joint is increased by 33%relative to the higher Mg-content barriers due to lower *** system exhibited good interfacial compatibility and showed little change with aging at 673 K for 20 days.

关键词： Mg_(3)Sb_(2) Mg_(1.2)SbNi Barrier layer Conversion efficiency

ZmCER1,a putative ECERIFERUM 1 protein in maize,functions in cuticular wax biosynthesis and bulliform cell development

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The Crop Journal 2024年第3期12卷 743-752页

作者： Yan Zhao Qingzhi Liu Xueran Wang Weixiao zhang Wei Xu yongzhong zhang Baoshen Liu College of Agronomy Shandong Agricultural UniversityTai’an 271018ShandongChina Qingdao Academy of Agricultural Sciences Qingdao 266100ShandongChina

The cuticular wax,acting as the ultimate defense barrier,is essential for the normal morphogenesis of plant *** this importance,the connection between wax composition and leaf development has not been thoroughly *** this study,we characterized a new maize mutant,ragged leaf4(rgd4),which exhibits crinkled and ragged leaves starting from the sixth leaf *** phenotype of rgd4 is conferred by ZmCER1,which encoding an aldehyde decarbonylase involved in wax ***1 function deficient mutant displayed reduced cuticular wax density and disordered bulliform cells(BCs),while ZmCER1 overexpressing plants exhibited the opposite effects,indicating that ZmCER1 regulates cuticular wax biosynthesis and BCs ***,as the density of cuticular wax increased,the water loss rate of detached leaf decreases,suggesting that ZmCER1 is positively correlated with plant drought tolerance.

关键词： Ragged leaf ZmCER1 Cuticular wax Bulliform cells

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论人工智能透明度原则的法治化实现

政法论丛 2024年第2期 124-137页

作者：张永忠华南师范大学法学院、人工智能法律应用重点实验室广东广州510006

随人工智能应用范围不断扩大,透明度原则成为破解“算法黑箱”难题的钥匙。透明度原则包括形式透明和实质透明。形式透明是对人工智能基础信息的披露,使人工智能的部署使用处于非秘密状态。实质透明与人工智能的可解释性息息相关,强调... 详细信息

随人工智能应用范围不断扩大,透明度原则成为破解“算法黑箱”难题的钥匙。透明度原则包括形式透明和实质透明。形式透明是对人工智能基础信息的披露,使人工智能的部署使用处于非秘密状态。实质透明与人工智能的可解释性息息相关,强调对披露信息以可被理解的方式进行有意义解释,从而打破知识壁垒,使相关信息实现真正可知。透明度原则应在法治化实现上进行精细考量:在考虑现有技术条件的基础上,有必要根据监管机关和社会公众的能力不同有区别地对披露和解释的信息内容提出义务要求,并针对不同人工智能的风险程度采取分级分类分场景的执行标准,从保护用户与公众知情权行使、确保国家监管权落实两方面推动透明度原则实现。

关键词：人工智能治理透明度原则披露可解释性法治化

热处理对选区激光熔化制备Al-Mn-Mg-Sc-Zr合金微观组织和力学性能的影响

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稀有金属 2024年第3期48卷 325-335页

作者：翟梓棫潘炜梁博刘彦涛张永忠中国有研科技集团有限公司国家有色金属复合材料工程技术研究中心北京101407 有研金属复材技术有限公司北京101407 北京有色金属研究总院北京100088

利用选区激光熔化(SLM)成形技术制备了Al-Mn-Mg-Sc-Zr合金,测试了不同热处理工艺下材料的显微硬度和拉伸性能,得到力学性能最佳的热处理工艺为300℃/5 h,并利用扫描电镜(SEM)和透射电镜(TEM)分析了热处理对合金组织性能的影响。结果表明... 详细信息

利用选区激光熔化(SLM)成形技术制备了Al-Mn-Mg-Sc-Zr合金,测试了不同热处理工艺下材料的显微硬度和拉伸性能,得到力学性能最佳的热处理工艺为300℃/5 h,并利用扫描电镜(SEM)和透射电镜(TEM)分析了热处理对合金组织性能的影响。结果表明:沉积态微观组织由沿沉积高度方向交替生长的柱状晶与等轴晶及细小第二相粒子组成,少量纳米级Al_(3)Sc和Al_(6)Mn粒子分布于晶内。经过热处理后,初生Al_(3)Sc和Al_(6)Mn粒子长大,晶粒尺寸发生轻微的粗化现象。热处理态试样抗拉强度为(556±2.3)MPa,较沉积态试样提高21%;断后伸长率为14.2%±1.2%,较沉积态试样没有明显变化,这主要由于热处理后的大量纳米或微纳米级第二相弥散析出所产生的沉淀强化导致,弥散的第二相同时分布于晶界和晶粒内部。在SLM成形过程中产生的热应力会导致沉积态晶粒内部产生位错,位错会导致沉积态试样的应力-应变曲线在塑性变形阶段出现明显的波动现象,热处理后消除了位错,波动现象消失。热处理降低了合金的残余应力和位错密度,保证了合金的良好塑性。

关键词：选区激光熔化(SLM) 热处理 Al-Mn-Mg-Sc-Zr 微观组织力学性能

公共服务均等化视角下中国博物馆空间分布格局及其影响因素

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新余学院学报 2024年第4期29卷 97-106页

作者：唐璐温柔张永忠新余学院经济管理学院江西新余338004 新余学院艺术学院江西新余338004

以国家文物局公布的6183座博物馆为研究对象,运用平均最近邻指数、核密度估计等方法对中国博物馆的空间分布格局进行分析,进一步借助地理探测器模型探究其影响因素。结果表明:中国博物馆总体空间分布数量呈现东南密集、西北稀疏的非均... 详细信息

以国家文物局公布的6183座博物馆为研究对象,运用平均最近邻指数、核密度估计等方法对中国博物馆的空间分布格局进行分析,进一步借助地理探测器模型探究其影响因素。结果表明:中国博物馆总体空间分布数量呈现东南密集、西北稀疏的非均衡性格局;空间分布类型为显著集聚,高等级博物馆集聚程度更高;博物馆总体空间分布密度呈“多中心,带状扩散”格局,形成了京津冀、长三角、珠三角等密度高值核心区,沿十大城市群分布的密度中值与中高值区,不同等级博物馆空间分布密度差异明显;经济、社会、文化和政策等方面的影响因子均与博物馆的空间分布有较强的统计关联性,其中,区域经济发展水平和人口密度是影响其空间分布的核心因子,各因子对不同等级博物馆的空间分布影响程度差异较大。

关键词：公共服务博物馆空间分布地理探测器中国

安徽省三市大气污染物和绿地暴露对初治结核病患者病亡率的影响

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中国防痨杂志 2024年第1期46卷 75-84页

作者：赵嘉文张永忠李振华毛毅铖张菁菁胡成洋张秀军阚晓红安徽医科大学公共卫生学院流行病与卫生统计学系合肥230032 安徽省胸科医院结防科合肥230022 安徽省胸科医院科教科合肥230022 安徽医科大学人文医学学院人文医学系合肥230032

目的:探讨大气污染物和绿地暴露对初治结核病患者治疗期间病亡率的影响,从环境监测层面上为结核病患者的健康管理提供科学依据。方法:收集安徽省合肥市、淮南市、黄山市2015年1月1日至2020年12月31日的29519例初治结核病患者的数据。通... 详细信息

目的:探讨大气污染物和绿地暴露对初治结核病患者治疗期间病亡率的影响,从环境监测层面上为结核病患者的健康管理提供科学依据。方法:收集安徽省合肥市、淮南市、黄山市2015年1月1日至2020年12月31日的29519例初治结核病患者的数据。通过环境监测站收集大气污染物细颗粒物[空气动力学直径≤2.5μm的颗粒(particulate matter with an aerodynamic diameter≤2.5μm,PM_(2.5))]、可吸入颗粒物[空气动力学直径≤10μm的颗粒(particulate matter with an aerodynamic diameter≤10μm,PM_(10))]、一氧化碳(CO)、二氧化氮(NO_(2))数据。应用Cox比例风险模型计算大气污染物暴露与初治结核病患者病亡率的风险比(HR)及其95%置信区间(95%CI),同时结合绿地暴露进行亚组分析。结果:29519例结核病患者中,有369例(1.25%)在治疗期间死亡。多因素Cox回归分析结果显示,PM_(2.5)每增加10μg/m^(3),患者的死亡风险上升15.6%(HR=1.156,95%CI:1.146~1.165),PM_(10)每增加10μg/m^(3),患者的死亡风险上升18.3%(HR=1.183,95%CI:1.176~1.190),CO每增加0.10 mg/m^(3),患者的死亡风险上升6.7%(HR=1.067,95%CI:1.060~1.074),NO_(2)每增加10μg/m^(3),患者的死亡风险上升2.8%(HR=1.028,95%CI:1.019~1.037)。将绿地暴露按照四分位数(Q_(1)~Q_(4))由低到高进行分组后,大气污染物对病亡率的影响随绿地暴露的提升逐渐降低[以PM_(2.5)为例,其在250 m和500 m缓冲区归一化植被指数对病亡率的HR值,Q_(1)分别为1.218(95%CI:1.197~1.240)和1.231(95%CI:1.210~1.253),Q_(4)分别下降至1.125(95%CI:1.106~1.146)和1.138(95%CI:1.118~1.159)]。结论:大气污染物暴露是初治结核病患者治疗期间的危险因素,更高的绿化程度能够降低因暴露于大气污染物所导致的死亡风险。

关键词：结核空气污染物环境暴露回顾性研究因素分析,统计学

Research on development of in situ titanium matrix composites and in situ reaction thermodynamics of the reaction systems

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Journal of University of Science and Technology Beijing 2006年第6期13卷 551-557页

作者： Lifang Cai yongzhong zhang Likai Shi Haoqiang Yang Mingzhe Xi National Engineering Research Center for Nonferrous Metal Composites General Research Institute for Nonferrous Metals Beijing 100088 China

The in situ synthesis method for titanium matrix composites （TMCs） has obvious technical and economical advantages over other traditional methods. Ultrafine reinforcement particles were formed in situ by chemical reaction between elements or between elements and compounds. Using the approach, contamination at the composite matrix/reinforcement particle interface did not occur, interface bonding was good, and the reinforcement particle was thermodynamically stable. The stage of development of the preparation process for in situ TMCs as well as the thermodynamic analysis of the possible in situ reaction systems was described.

关键词： in situ titanium matrix composites reaction synthesis reaction system thermodynamic analysis

Microstructure and formation mechanism of titanium matrix composites coating on Ti-6Al-4V by laser cladding

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Rare Metals 2007年第4期26卷 342-346页

作者： CAI Lifang zhang yongzhong SHI Likai National Engineering Research Center for Nonferrous Metal Composites General Research Institute for Nonferrous Metals Beijing 100088 China

Laser cladding experiments were done on a 5-kW continuous wave CO2 laser to synthesize TiC and TiB rein- fowed titanium matrix composite coatings on Ti-6AI-4V alloy with a mixture of Ti and B4C precursor powder. The ther- modynamics of the reactions were calculated and analyzed. The microstructure and phase evolution of TiB and TiC com- posites were investigated. The results showed that the chemical reaction between Ti and B4C would release much heat, and these compounds, TiC, TiB, and small amount of TiB2, can be formed on the surface of Ti-6AI-4V alloy if the supplied en- ergy is sufficient to excite the reaction among the initial products. A good metallurgical bond between the coating and the substrate can be achieved. The microhardness of coating was irregular and the maximum value was approximately HV600.

关键词： coatings titanium matrix composites (TMCs) laser cladding, in situ formation

Interfacial microstructure and properties of diamond/Cu-xCr composites for electronic packaging applications

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Rare Metals 2011年第1期30卷 94-98页

作者： zhang Ximin GUO Hong YIN Fazhang FAN Yeming zhang yongzhong National Engineering Research Center for Nonferrous Metals Composites General Research Institute for Non-ferrous MetalsBeijing 100088China

Diamond/Cu-xCr composites were fabricated by pressure infiltration *** thermal conductivities of diamond/Cu-xCr（x = 0.1,0.5,0.8） composites were above 650 W/mK,higher than that of diamond/Cu *** tensile strengths ranged from 186 to 225 MPa,and the bonding strengths ranged from 400 to 525 *** of Cr element on the thermo-physical properties and interface structures were *** intermediate layer was confirmed as Cr3C2 and the amount of Cr3C2 increased with the increase of Cr concentration in Cu-xCr *** the Cr concentration was up to 0.5 wt.%,the content of the Cr3C2 layer was *** the thickness of the Cr3C2 layer became larger,the composites showed a lower thermal conductivity but higher mechanical *** coefficients of thermal expansion（CTE） of diamond/Cu-xCr（x = 0.1,0.5,0.8） composites were in good agreement with the predictions of the Kerner＇ model.

关键词： composite materials copper interfaces bonding electronic packaging infiltration

Experimental investigations on the fluid flow mechanism in porous media of enhanced oil recovery by alkli/surfactant/polymer flooding

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Science China(Technological Sciences) 2005年第4期48卷 454-467页

作者： WANG Jialu SHEN Pingping CHEN yongzhong zhang Zubo JIA Xu TIAN Yuling Research Institute of Petroleum Exploration and Development Beijing 100083 China Research Institute of Petroleum Exploration and Development Beijing 100083 China Research Institute of Petroleum Exploration and Development Beijing 100083 China Research Institute of Petroleum Exploration and Development Beijing 100083 China Research Institute of Petroleum Exploration and Development Beijing 100083 China Research Institute of Petroleum Exploration and Development Beijing 100083 China

The fluid flow mechanism in porous media of enhanced oil recovery by Alkli/ Surfactant/Polymer (ASP) flooding is investigated by measuring production performance, pressure distribution and saturation distribution through installing differential pressure transducers and saturation measuring probes in a physical model of vertical heterogeneous reservoir. The fluid flow variation in porous media is the main reason of enhanced oil recovery of ASP flooding. The pressure field and saturation field are nonlinearly coupled together and the interaction between them results in the fluid flow variation in the reservoir. In a vertical heterogeneous reservoir, the ASP agents initially flow in the high permeability layers because the resistance in the high permeability layer is increased under the physical and chemical action of adsorption, retention and emulsion. ASP flooding displaces out not only the residual oil in the high permeability layer, but also the remaining oil in the low and the middle permeability layers by increasing swept volume and displacing efficiency.

关键词： ASP flooding, vertical heterogeneous reservoir, enhanced oil recovery, fluid flow mechanism in porous media.