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A-Site Effect on the Conversion of Bio-Ethanol into Isobutene over Ternary A1ZnyZrzOn Catalysts
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作者 Feng Liu Yong Men +3 位作者 jinguo wang Xiaoxiong Huang Biao Zhao Rong He 《Modern Research in Catalysis》 CAS 2016年第3期95-101,共7页
Ternary multifunctional A<sub>1</sub>Zn<sub>y</sub>Zr<sub>z</sub>O<sub>n</sub> catalysts are prepared by introducing A-site transition metals with the redox capability i... Ternary multifunctional A<sub>1</sub>Zn<sub>y</sub>Zr<sub>z</sub>O<sub>n</sub> catalysts are prepared by introducing A-site transition metals with the redox capability into binary Zn<sub>1</sub>Zr<sub>8</sub>O<sub>n</sub>. Structure and morphology were investigated by means of XRD, BET and FESEM, respectively. Activity data showed that Cr addition exhibited obvious beneficial effect to promote isobutene production from direct conversion of bio-ethanol compared to other A-site metal dopants. A significant higher yield of isobutene over Cr-promoted Zn<sub>1</sub>Zr<sub>8</sub>O<sub>n</sub> catalyst was also observed with respect to its binary Zn<sub>1</sub>Zr<sub>8</sub>O<sub>n</sub> counterpart. The choice of A-site metal is of prime importance in the isobutene production, catalyzing mainly the ethanol dehydrogenation, meanwhile the appropriate addition of zinc on the catalyst surface is also essential for good isobutene yield. 展开更多
关键词 A1Zn1Zr8On Bio-Ethanol to Isobutene Multifunctional Catalysts The Redox Capability Dehydrogenation
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Methanol Steam Reforming over Na-Doped ZnO-Al2O3 Catalysts
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作者 Di Liu Yong Men +2 位作者 jinguo wang Xin Liu Qiuyan Sun 《American Journal of Analytical Chemistry》 2016年第7期568-575,共8页
In this study, the catalyst composition in binary ZnO-Al<sub>2</sub>O<sub>3</sub> catalyst was initially evaluated and optimized for methanol steam reforming. Then different Na contents were lo... In this study, the catalyst composition in binary ZnO-Al<sub>2</sub>O<sub>3</sub> catalyst was initially evaluated and optimized for methanol steam reforming. Then different Na contents were loaded by an incipient wetness impregnation method onto the optimized ZnAl catalyst. It was found that the activity was greatly enhanced by the modification of Na, which depended on the Na content in the catalyst. The methanol conversion was 96% on a 0.1 Na/0.4 ZnAl catalyst (GHSV = 14,040 h<sup>-</sup><sup>1</sup>, S/C = 1.4, 350°C), which was much higher with respect to a Na-free 0.4 ZnAl catalyst (74%). The remarkable improvement of activity was attributed to a weakening of the C-H bonds and clear of hydroxyl group by the Na dopant leading to an accelerated dehydrogenation of the reaction intermediates formed on ZnAl<sub>2</sub>O<sub>4</sub> spinel surface and thus the overall reaction. 展开更多
关键词 Methanol Steam Reforming Hydrogen Production ZnO-Al2O3 Catalyst Na-Promotion Activity
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Quantifying the impact of mineralogical heterogeneity on reactive transport modeling of CO_(2)+O_(2) in-situ leaching of uranium 被引量:2
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作者 Yun Yang Wenjie Qiu +5 位作者 Zhengbang Liu Jian Song Jianfeng Wu Zhi Dou jinguo wang Jichun Wu 《Acta Geochimica》 EI CAS CSCD 2022年第1期50-63,共14页
CO_(2)+O_(2) in-situ leaching(ISL)of sandstonetype uranium ore represents the third generation of solution mining in China.In this study,reactive transport modeling of the interaction between hydrodynamic and geochemi... CO_(2)+O_(2) in-situ leaching(ISL)of sandstonetype uranium ore represents the third generation of solution mining in China.In this study,reactive transport modeling of the interaction between hydrodynamic and geochemical reactions is performed to enable better prediction and regulation of the CO_(2)+O_(2) in-situ leaching process of uranium.Geochemical reactions between mining solutions and rock,and the kinetic uranium dissolution controlled by O_(2)(aq)and bicarbonate(HCO_(3)-)are considered in the CO_(2)+O_(2) ISL reactive transport model of a typical sandstone-hosted uranium ore deposit in northern China.The reactive leaching of uranium is most sensitive to the spatial distribution of the mineralogical properties of the uranium deposit.Stochastic geostatistical models are used to represent the uncertainty on the spatial distribution of mineral grades.A Monte Carlo analysis was also performed to simulate the uranium production variability over an entire set of geostatistical realizations.The ISL stochastic simulation performed with the selected geostatistical realizations approximates the uranium production variability well.The simulation results of the ISL reactive transport model show that the extent of the uranium plume is highly dependent on mineralogical heterogeneity.The uncertainty analysis suggests the effect of uranium grade heterogeneity was found to be important to improve the accurate capture of the uncertainty.This study provides guidance for the accurate simulation and dynamic regulation of the CO_(2)+O_(2) leaching process of uranium at the scale of large mining areas. 展开更多
关键词 In-situ leaching Reactive transport HETEROGENEITY Stochastic geostatistical model Monte Carlo analysis Uranium grade
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Effect of chromium interlayer thickness on interfacial thermal conductance across copper/diamond interface 被引量:2
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作者 Xiaoyan Liu Fangyuan Sun +8 位作者 Wei wang Jie Zhao Luhua wang Zhanxun Che Guangzhu Bai Xitao wang jinguo wang Moon JKim Hailong Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第11期2020-2031,共12页
The thermal conductivity of diamond particles reinforced copper matrix composite as an attractive thermal management material is significantly lowered by the non-wetting heterointerface.The paper investigates the heat... The thermal conductivity of diamond particles reinforced copper matrix composite as an attractive thermal management material is significantly lowered by the non-wetting heterointerface.The paper investigates the heat transport behavior between a 200-nm Cu layer and a single-crystalline diamond substrate inserted by a chromium(Cr)interlayer having a series of thicknesses from 150 nm down to 5 nm.The purpose is to detect the impact of the modifying interlayer thickness on the interfacial thermal conductance(h)between Cu and diamond.The time-domain thermoreflectance measurements suggest that the introduction of Cr interlayer dramatically improves the h between Cu and diamond owing to the enhanced interfacial adhesion and bridged dissimilar phonon states between Cu and diamond.The h value exhibits a decreasing trend as the Cr interlayer becomes thicker because of the increase in thermal resistance of Cr interlayer.The high h values are observed for the Cr interlayer thicknesses below 21 nm since phononic transport channel dominates the thermal conduction in the ultrathin Cr layer.The findings provide a way to tune the thermal conduction across the metal/nonmetal heterogeneous interface,which plays a pivotal role in designing materials and devices for thermal management applications. 展开更多
关键词 SPUTTERING DIAMOND metal/nonmetal interface interfacial thermal conductance time-domain thermoreflectance
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Methodology for Extraction of Tunnel Cross-Sections Using Dense Point Cloud Data 被引量:2
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作者 Yueqian SHEN jinguo wang +2 位作者 Jinhu wang Wei DUAN Vagner G.FERREIRA 《Journal of Geodesy and Geoinformation Science》 2021年第2期56-71,共16页
Tunnel deformation monitoring is a crucial task to evaluate tunnel stability during the metro operation period.Terrestrial Laser Scanning(TLS)can collect high density and high accuracy point cloud data in a few minute... Tunnel deformation monitoring is a crucial task to evaluate tunnel stability during the metro operation period.Terrestrial Laser Scanning(TLS)can collect high density and high accuracy point cloud data in a few minutes as an innovation technique,which provides promising applications in tunnel deformation monitoring.Here,an efficient method for extracting tunnel cross-sections and convergence analysis using dense TLS point cloud data is proposed.First,the tunnel orientation is determined using principal component analysis(PCA)in the Euclidean plane.Two control points are introduced to detect and remove the unsuitable points by using point cloud division and then the ground points are removed by defining an elevation value width of 0.5 m.Next,a z-score method is introduced to detect and remove the outlies.Because the tunnel cross-section’s standard shape is round,the circle fitting is implemented using the least-squares method.Afterward,the convergence analysis is made at the angles of 0°,30°and 150°.The proposed approach’s feasibility is tested on a TLS point cloud of a Nanjing subway tunnel acquired using a FARO X330 laser scanner.The results indicate that the proposed methodology achieves an overall accuracy of 1.34 mm,which is also in agreement with the measurements acquired by a total station instrument.The proposed methodology provides new insights and references for the applications of TLS in tunnel deformation monitoring,which can also be extended to other engineering applications. 展开更多
关键词 CROSS-SECTION control point convergence analysis z-score method terrestrial laser scanning dense point cloud data
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腹腔镜胆囊切除术难度评分系统在急性胆囊炎治疗中的应用价值
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作者 孟塬 巴合提·卡力甫 +6 位作者 马志刚 王锦国 张杰 李玉鹏 宋巍 田广磊 陈雄 《中华肝脏外科手术学电子杂志》 CAS 2024年第2期169-175,共7页
目的:探讨腹腔镜胆囊切除术难度评分系统(DiLCs)在急性胆囊炎腹腔镜胆囊切除术(LC)治疗中的应用价值。方法:回顾性分析2016年5月至2019年1月在新疆维吾尔自治区人民医院行LC的158例急性胆囊炎患者临床资料。其中男88例,女70例;平均年龄(... 目的:探讨腹腔镜胆囊切除术难度评分系统(DiLCs)在急性胆囊炎腹腔镜胆囊切除术(LC)治疗中的应用价值。方法:回顾性分析2016年5月至2019年1月在新疆维吾尔自治区人民医院行LC的158例急性胆囊炎患者临床资料。其中男88例,女70例;平均年龄(60±18)岁。患者均签署知情同意书,符合医学伦理学规定。分别采用DiLCs评分系统和急性胆囊炎京东指南2018(TG18)分级系统对患者围手术期指标进行分析,两个分级系统与临床指标相关性分析采用单因素方差分析、秩和检验等;采用ROC曲线下面积(AUC)对两个系统进行比较。结果:随着两种评分系统评分增加,WBC、手术时间、术中出血量、住院时间、胆囊造瘘率、中转开腹率等急性胆囊炎相关指标增加,差异有统计学意义(P<0.05)。TG18和DiLCs评估并发症的AUC分别为0.889(95%CI:0.829~0.933)和0.509(95%CI:0.428~0.598),TG18明显优于DiLCs(Z=3.795,P<0.05)。DiLCs和TG评估中转开腹率的AUC分别为0.697(95%CI:0.619~0.768)和0.746(95%CI:0.670~0.811),差异无统计学意义(Z=0.829,P>0.05)。DiLCs和TG评估胆囊造瘘率的AUC分别为0.664(95%CI:0.584~0.737)和0.770(95%CI:0.697~0.833),差异无统计学意义(Z=1.639,P>0.05)。结论:DiLCs可有效评估患者手术难度和治疗方式选择,其评估能力与TG18一致,而在手术风险预测等方面弱于TG18。 展开更多
关键词 急性胆囊炎 胆囊切除术 腹腔镜 手术难度 评分系统
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Deformation-induced α_2/γ Interfaces in a Hot-deformed Ti-45Al-10Nb Alloy
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作者 jinguo wang Lichun ZHANG and Guoliang CHEN (State Key Lab. for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China )Henqiang YE(Lab. of Atomic Imaging of Solids, Institute of Metal Research, Chinese Academy 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1998年第2期132-138,共7页
The structure change of α2/γ interface in a Ti-45Al-10Nb alloy induced by hot deformation was investigated by conventional and high-resolution transmission eIectron microscopy. Two types of hot deformation induced s... The structure change of α2/γ interface in a Ti-45Al-10Nb alloy induced by hot deformation was investigated by conventional and high-resolution transmission eIectron microscopy. Two types of hot deformation induced special α2/γ intedeces, coherent intedeces with high density of ledges and semi-coherent α2/γ intedeces were found to be due to the absorption of mobile dislocations into the α2/γ inteface. For the misoriented semi-coherent α2/γ interfaces, the densities of dislocation ledges increase with the misoriented angle between (111)γ and (0001)α2 planes, and 1/3[111] Frank partial dislocations were involved in the dislocation ledges. Formation mechanism of these deformation-induced α2/γ interfaces was discussed to be related to the role of α2/γ interface5 adjusting the deformation as a dislocation sink absorbing the slipping dislocations in the γ phase 展开更多
关键词 Al TI Interfaces in a Hot-deformed Ti-45Al-10Nb Alloy Deformation-induced
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伊朗的阿富汗难民政策:动因、演变及影响因素 被引量:4
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作者 杨勇 汪金国 《世界民族》 CSSCI 北大核心 2021年第4期88-98,共11页
伊朗在考虑宗教、经济和地缘政治等因素的基础上,以伊朗国家利益为出发点调整对阿富汗难民的政策。本文把伊朗的阿富汗难民政策演变划分为四个阶段:第一阶段,苏联入侵阿富汗时期(1978—1991年),该阶段伊朗实施的是全面接收阿富汗难民政... 伊朗在考虑宗教、经济和地缘政治等因素的基础上,以伊朗国家利益为出发点调整对阿富汗难民的政策。本文把伊朗的阿富汗难民政策演变划分为四个阶段:第一阶段,苏联入侵阿富汗时期(1978—1991年),该阶段伊朗实施的是全面接收阿富汗难民政策。第二阶段,阿富汗内战及塔利班执政时期(1992—2001年),该阶段实施的是鼓励自愿遣返阿富汗难民的政策。第三阶段,美国在阿富汗进行反恐战争时期(2002—2011年),该阶段实施的是强制遣返阿富汗难民的政策。第四阶段,叙利亚危机爆发时期(2012至今),该阶段实施的是放缓强制遣返阿富汗难民的政策。阿富汗难民给伊朗带来了不小的社会负担,但在地缘政治层面又增添了伊朗与美国、阿富汗等国家博弈的筹码。 展开更多
关键词 伊朗 阿富汗难民 难民政策
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乌克兰国家认同的建构:挑战和转向 被引量:1
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作者 汪金国 曹佳鲁 《中央社会主义学院学报》 2020年第1期162-170,共9页
在独立后甚至在危机后,乌克兰国家认同的建构取得了一定成效。一是充分适应乌克兰民族的现状,对俄语和其他少数民族语言采取相对包容的态度,使得乌克兰人在语言政策方面的对抗在一定程度上得到缓和。二是改变乌克兰关于第二次世界大战... 在独立后甚至在危机后,乌克兰国家认同的建构取得了一定成效。一是充分适应乌克兰民族的现状,对俄语和其他少数民族语言采取相对包容的态度,使得乌克兰人在语言政策方面的对抗在一定程度上得到缓和。二是改变乌克兰关于第二次世界大战历史的记忆,摒弃苏联意识形态,转向欧洲思维,建立属于乌克兰人自己的战争史,从历史的深处挖掘国家认同的因素。三是通过网络社交群众参与,激发国民的团结和爱国热情,维护国家统一和领土完整,同时也在网络层面采取"去俄罗斯化"的态度,建立起独立自主的网络安全空间。乌克兰在国家认同的构建过程中,力求保持政治稳定和潜移默化的特点,保证了政策的平稳执行,但也使得政策的完整性、连贯性和有效性明显不足。 展开更多
关键词 国家认同 乌克兰 历史记忆
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Global prediction system for COVID-19 pandemic 被引量:17
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作者 Jianping Huang Li Zhang +13 位作者 Xiaoyue Liu Yun Wei Chuwei Liu Xinbo Lian Zhongwei Huang Jifan Chou Xingrong Liu Xun Li Kehu Yang jinguo wang Hongbin Liang Qianqing Gu Pengyue Du Tinghan Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2020年第22期1884-1887,M0003,共5页
The outbreak of a novel coronavirus(SARS-CoV-2)has resulted in a worldwide pandemic infecting over 5.9 million people[1].This positive-strand RNA virus can cause severe respiratory distress syndrome in humans(COVID-19... The outbreak of a novel coronavirus(SARS-CoV-2)has resulted in a worldwide pandemic infecting over 5.9 million people[1].This positive-strand RNA virus can cause severe respiratory distress syndrome in humans(COVID-19),with over 364,000 deaths between December 2019 and May 30,2020[1,2].To combat this pandemic,the World Health Organization(WHO)is coordinating global efforts on surveillance,epidemiology,mathematical model-ing,diagnostics,treatment and control,and has issued interim guidance to countries.Nevertheless,this is a difficult situation and the number of cases is rapidly increasing globally.The tempo-ral evolution and the spatial spread of this virus have also raised serious concerns about the future trajectory of this outbreak. 展开更多
关键词 病毒性肺炎 预测系统 环境数据 全球公共卫生 气候预测 非洲地区 管控措施 实时更新
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论俄罗斯边疆地区的俄罗斯族人口流失问题——以达吉斯坦共和国为例
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作者 汪金国 杨忞 《世界民族》 CSSCI 北大核心 2022年第6期29-44,共16页
自20世纪70年代始,苏联边疆地区的人口在民族构成上逐渐呈现出“本地化”趋势,即外来民族,主要是俄罗斯族人趋于减少,这在民族结构复杂、问题突出的北高加索地区表现得尤为突出。达吉斯坦共和国作为俄罗斯在北高加索地区面积最大、人口... 自20世纪70年代始,苏联边疆地区的人口在民族构成上逐渐呈现出“本地化”趋势,即外来民族,主要是俄罗斯族人趋于减少,这在民族结构复杂、问题突出的北高加索地区表现得尤为突出。达吉斯坦共和国作为俄罗斯在北高加索地区面积最大、人口最多,民族成分最为多样化的主体,其境内俄罗斯族人口的变迁在一定程度上体现了俄罗斯边疆区,尤其是北高加索地区的人口民族结构变化。本文以达吉斯坦共和国境内俄罗斯族人口数量、比例变化为主要线索,全景式展现20世纪60年代以来,该地区俄罗斯族人口减少的整体趋势,剖析导致这一现象的主客观原因,阐释其影响,判断其未来走势,以期为多民族国家边疆治理和俄罗斯人口问题研究提供新的启发和思考。 展开更多
关键词 俄罗斯 边疆地区 俄罗斯族人 人口流失 达吉斯坦
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