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Preparation of Pd/c-Al_(2)O_(3)/nickel foam monolithic catalyst and its performance for selective hydrogenation in a rotating packed bed reactor

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Chinese Journal of Chemical Engineering 2022年第1期35卷 311-319页

作者： Hai-Long Liao Bao-Ju Wang Ya-Zhao Liu yong Luo Jie-Xin Wang guang-Wen chu Jian-Feng Chen State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China

Selective hydrogenation plays an important role in chemical industries,yet its selectivity is usually limited by the mass *** this work,the enhanced hydrogenation selectivity was achieved in a rotating packed bed(RPB)reactor with excellent mass transfer *** to be used under the centrifugal filed,a monolithic catalyst Pd/c-Al_(2)O_(3)/nickel foam suiting for the shape and size of the rotor of RPB reactor was prepared by the electrophoretic deposition *** mechanical strength of the catalyst can meet the requirement of high centrifugal force in the *** hydrogenation selectivity in the RPB reactor using the 3-methyl-1-pentyn-3-ol hydrogenation system was 3–8 times higher than that in a stirred tank reactor under similar *** work proves the feasibility of intensifying the selectivity of hydrogenation process in the RPB reactor.

关键词： Monolithic catalyst Rotating packed bed reactor Hydrogenation Selectivity

Construction of Normal Bimagic Squares of Order 2u

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 771-789页

作者： Wen LI Feng-chu PAN guang-zhou CHEN School of Science Xichang UniversityXichang 615000China School of Environment and Resource Xichang UniversityXichang 615000China Henan Engineering Laboratory for Big Data Statistical Analysis and Optimal Control School of Mathematics and Information ScienceHenan Normal UniversityXinxiang 453007China

An n×n matrix A consisting of nonnegative integers is a general magic square of order n if thesum of elements in each row,column,and main diagonal is the same.A general magic square A of order n iscalled a magic square,denoted by MS(n),if the entries of A are distinct.A magic square A of order n is normalif the entries of A are n^2 consecutive *** A^*d denote the matrix obtained by raising each elementof A to the d-th *** matrix A is a d-multimagic square,dcnoted by MS(n,d),if A^*e is an MS(n)for 1≤e≤*** this paper we investigate the existence of normal bimagic squares of order 2u and prove that thereexists a normal bimagic square of order 2u,where u and 6 are coprime and u≥5.

关键词： magic square bimagic square complementary pair multimagic square Latin square

老年人群中视听障碍对主观幸福感的影响:抑郁倾向的中介作用

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复旦学报（医学版） 2024年第4期51卷 558-565页

作者：刘叶高广峰周亦凡凯维萨·阿布杜许库尔汪楚楚罗剑锋复旦大学公共卫生学院生物统计学教研室上海200032 国家卫生健康委员会卫生技术评估重点实验室(复旦大学) 上海200032 公共卫生安全教育部重点实验室(复旦大学) 上海200032 上海市嘉定区中医院院长室上海201800 上海市第十人民医院眼科上海200072

目的探讨视听障碍(audio-visual impairments)对主观幸福感(subjective well-being,SWB)的影响,以及抑郁倾向是否中介了视听障碍与主观幸福感之间的关联。方法中国健康与退休纵向调查(The China Health and Retirement Longitudinal Survey,CHARLS)对45岁及以上的中老年人进行问卷调查,在全国30个省级行政单位中采用多阶段抽样,分别在县(区)-村(居)-家户-个人层面上进行抽样,并在县(区)-村(居)两级抽样中,采用按人口规模成比例的概率(proportional probability sampling,PPS)抽样,最终纳入了28个省份150个县(区)的450个村/社区。本研究基于2018年的CHARLS数据展开研究,纳入标准为:(1)年龄≥60岁;(2)有完整的自我报告的视力和听力状况;(3)至少含有生活满意度、主观期望寿命、自评健康状况3项主观幸福感指标中的一个。CHARLS使用Likert五分量表测定老年人的主观幸福感,使用10项流调中心抑郁自评量表(the Center for Epidemiology Studies Depression Scale-10,CESD-10)测定老年人的抑郁倾向。本研究采用多元回归分析视听障碍与抑郁倾向、主观幸福感之间的关联,并通过中介模型分析抑郁倾向的中介作用。双侧P值<0.05被认为有统计学意义。结果最终纳入符合标准的研究对象7620人。其中有视听障碍的患者抑郁倾向水平明显更高,主观幸福感的三项指标均较低(P值均小于0.05)。视觉障碍、听觉障碍和视听双重障碍与更高的抑郁倾向水平和更低的自评健康、主观期望寿命有关;视觉障碍和视听双重障碍与较低的生活满意度有关。抑郁倾向在视听双重障碍与生活满意度间及视觉障碍、听觉障碍、视听双重障碍与自评健康和主观期望寿命间起部分中介作用。结论在中国老年人群中,视听障碍与较低的主观幸福感状态有关,抑郁倾向在其中起着中介作用。

关键词：中国健康与退休纵向调查(CHARLS) 生活满意度主观期望寿命自评健康抑郁倾向视听障碍老年人

未来变化环境下大汶河流域济南段生态流量评价

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中国农村水利水电 2024年第6期 124-131,139页

作者：侯恩光冯平孙影林庆辉褚伟谭秀翠济南市水文中心山东济南250002 山东农业大学山东泰安271018

生态流量是河流生态系统健康稳定的基础,在全球气候变化和人类活动增强的背景下,生态流量受到的影响日益显著。为探究大汶河流域生态流量对未来变化环境的响应,以大汶河流域济南段为研究对象,采用SWAT模型分析未来土地利用和气候情景下... 详细信息

生态流量是河流生态系统健康稳定的基础,在全球气候变化和人类活动增强的背景下,生态流量受到的影响日益显著。为探究大汶河流域生态流量对未来变化环境的响应,以大汶河流域济南段为研究对象,采用SWAT模型分析未来土地利用和气候情景下径流时空变化规律,评价大汶河水资源调度控制断面陈北、马小庄生态流量保证率,探究其对未来变化环境的响应规律。结果表明:未来变化环境下,大汶河流域济南段土地利用呈现耕地面积减小,城镇面积增大的特点;气候变化呈现降水量增多,温度上升的特点。未来土地利用变化引起径流减少2%,未来气候影响径流减少1%~4%,而两者共同作用,径流减少3%~5%,未来气候变化减弱了降水与径流的相关性。空间上,未来土地利用变化增强径流量空间正相关性,而未来气候变化减弱了径流量的空间正相关性及其显著性水平,且影响径流量空间分布特征。未来土地利用变化对陈北、马小庄流量及生态流量保证率影响较小,而未来气候变化改变了陈北、马小庄流量过程线的形态,将陈北、马小庄生态流量保证率由73%、74%提高到97%、98%,基本生态流量保证率90%以上占比由14%提高至93%。未来土地利用与气候因素中,降水量是陈北、马小庄生态流量保证率的主控因子。研究结果可为大汶河流域生态调度与管理,应对变化环境提供技术支持。

关键词：土地利用变化气候变化生态流量 SWAT 全局莫兰指数

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水稻无人机直播产量、效益分析及技术要点

中国稻米 2024年第1期30卷 98-100,107页

作者：童纪氚戎雪利任萍褚光王丹英慈溪市农业机械化技术推广中心浙江慈溪315300 中国水稻研究所杭州310006 余姚市农业机械化技术推广中心浙江余姚315400

以常规水稻品种秀水14为供试品种,比较了机械插秧、行走式机械直播和无人机直播3种种植方式的产量、成本和效益,分析了不同种植方式的工作效率与群体均匀性。结果表明,无人机直播的产量与机械插秧、行走式机械直播无显著差异,但其具有... 详细信息

以常规水稻品种秀水14为供试品种,比较了机械插秧、行走式机械直播和无人机直播3种种植方式的产量、成本和效益,分析了不同种植方式的工作效率与群体均匀性。结果表明,无人机直播的产量与机械插秧、行走式机械直播无显著差异,但其具有播种效率高、群体生长均衡、种植成本低的特点。最后小结了无人机直播技术要点。

关键词：水稻机械插秧行走式机械直播无人机直播

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Computational fluid dynamic simulation of gas-liquid flow in rotating packed bed:A review

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Chinese Journal of Chemical Engineering 2022年第1期35卷 85-108页

作者： Wen-Cong Chen Ya-Wei Fan Liang-Liang Zhang Bao-Chang Sun yong Luo Hai-Kui Zou guang-Wen chu Jian-Feng Chen Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China StateKey Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

The rotating packed bed(RPB)has been widely used in gas-liquid flow systems as a process intensification device,exhibiting excellent mass transfer enhancement ***,the complex internal structure and the high-speed rotation of the rotor in RPB bring significant challenges to study the intensification mechanism by experiment *** the past two decades,Computational fluid dynamics(CFD)has been gradually applied to simulate the hydrodynamics and mass transfer characteristics in RPB and instruct the reactor *** article covers the development of the CFD simulation of gasliquid flow in ***,the improvement of the simulation method in the aspect of mathematical models,geometric models,and solving methods is ***,new progress of CFD simulation about hydrodynamic and mass transfer characteristics in RPB is reviewed,including pressure drop,velocity distribution,flow pattern,and concentration distribution,*** new phenomena such as the end effect area with the maximum turbulent have been revealed by this *** addition,the exploration of developing new reactor structures by CFD simulation is introduced and it is proved that such new structures are competitive to different *** defects of current research and future development directions are also discussed at last.

关键词： Rotating packed bed Computational fluid dynamics Simulation Hydrodynamics Mass transfer

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锥形电活性聚合物薄膜作动器的力电响应研究

金陵科技学院学报 2024年第1期40卷 72-78页

作者：楚翔宇缪广红李顺袁成安徽理工大学土木建筑学院安徽淮南232001 安徽理工大学力学与光电物理学院安徽淮南232001

以一款锥形电活性聚合物薄膜作动器为研究对象,选用Ogden材料模型对作动器进行数值计算。控制外力变化,对薄膜在变形状态下的应变量、厚度及临界电场强度进行分析,研究了预拉伸对薄膜力电稳定性的影响。结果表明:外力增加会显著提高薄... 详细信息

以一款锥形电活性聚合物薄膜作动器为研究对象,选用Ogden材料模型对作动器进行数值计算。控制外力变化,对薄膜在变形状态下的应变量、厚度及临界电场强度进行分析,研究了预拉伸对薄膜力电稳定性的影响。结果表明:外力增加会显著提高薄膜内各点的径向应变,减小膜厚,并使得临界电场强度的分布发生改变;薄膜预拉伸程度的增加,也会提高薄膜临界电场强度,使得薄膜的力电稳定性得到增强。

关键词：锥形电活性聚合物薄膜作动器预拉伸临界电场强度力电稳定性

N1,N12-二乙酰精胺在肠癌中的含量水平及其临床早期诊断意义

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辽宁大学学报（自然科学版） 2024年第1期51卷 45-51页

作者：牟藤初廷广李文欣董千泽刘勇大连理工大学生物医学工程学院辽宁大连116086 辽宁大学考古文博学院辽宁沈阳110136 辽宁迈迪生物科技股份有限公司辽宁本溪117004 中国医科大学基础医学院辽宁沈阳110122

目的分析N1,N12-二乙酰精胺(N1,N12-diacetylspermine, DiAcSpm)在肠癌组织中的含量水平以及临床早期诊断意义.方法通过免疫组织化学方法检测60例肠癌组织以及22例癌旁健康组织中DiAcSpm的含量水平.采用卡方检验方法分析DiAcSpm的含... 详细信息

目的分析N1,N12-二乙酰精胺(N1,N12-diacetylspermine, DiAcSpm)在肠癌组织中的含量水平以及临床早期诊断意义.方法通过免疫组织化学方法检测60例肠癌组织以及22例癌旁健康组织中DiAcSpm的含量水平.采用卡方检验方法分析DiAcSpm的含量水平与各临床病理因素之间的关系.结果肠癌组织中DiAcSpm的阳性染色比率为75.0%,明显高于癌旁健康组织的22.7%.DiAcSpm的较高含量水平与患者的细胞核增殖指数(Ki-67)显著相关,而与患者的年龄、性别、肿瘤的分化程度以及肿瘤的国际临床病期分类(TNM)无显著相关性.结论 DiAcSpm含量水平升高与肠癌的持续快速增殖有关,可以作为早期诊断肠癌的一种重要分子标记物.

关键词： N1 N12-二乙酰精胺肠癌早期诊断

Progressive Furniture Model Decimation with Texture Preservation

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Journal of Computer Science & Technology 2019年第6期34卷 1258-1268页

作者： Zhi-guang Pan chu-Hua Xian Shuo Jin Gui-Qing Li School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China BlueFire AI CentralHong KongChina

In digital furniture design, skillful designers usually use professional software to create new furniture designs with various textures and then take advantage of rendering tools to produce eye-catching design results. Generally, a fine-grained furniture model holds many geometric details, inducing significant time cost to model rendering and large data size for storage that are not desired in application scenarios where efficiency is greatly emphasized. To accelerate the rendering process while keeping good rendering results as many as possible, we develop a novel decimation technique which not only reduces the number of faces on furniture models, but also retains their geometric and texture features. Two metrics are utilized in our approach to measure the distortion of texture features. Considering these two metrics as guidance for decimation, high texture distortion can be avoided in simplifying the geometric models. Therefore, we are able to build multi-level representations with different detail levels based on the initial design. Our experimental results show that the developed technique can achieve excellent visual effects on the decimated furniture model.

关键词： furniture design model decimation texture preservation progressive representation