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西欧兔“碳循”世界
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作者 舒蕾 段自敏 +5 位作者 康钰燊 赵子健 王宏 朱丽华 熊辉 王楠 《大学化学》 CAS 2024年第5期144-153,共10页
随着国家“双碳”战略的推进,作为“主角”的二氧化碳(CO_(2))逐渐被人们所关注。然而,大众对CO_(2)循环及碳减排等缺乏系统、深入的理解。本实验开发了一套碳循环实验,包含CO_(2)的性质、产生、转化及捕集,通过光合作用和化学吸收等分... 随着国家“双碳”战略的推进,作为“主角”的二氧化碳(CO_(2))逐渐被人们所关注。然而,大众对CO_(2)循环及碳减排等缺乏系统、深入的理解。本实验开发了一套碳循环实验,包含CO_(2)的性质、产生、转化及捕集,通过光合作用和化学吸收等分别模拟自然界与工业固碳减排过程,实现碳减排、碳中和。通过指示剂变色、喷泉及沉淀等多种形式展示CO_(2)的变化过程。实验原料多取自生活,操作简单;互动方案丰富,趣味性高,生动科普碳循环的化学原理,普及“双碳”知识,让低碳节能理念深入人心。 展开更多
关键词 碳循环 光合作用 碳捕集 指示剂 喷泉实验
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“双碳”相关实验开发——蛋壳源CaO的制备、表征及其碳捕集性能
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作者 舒蕾 郝正清 +4 位作者 闫凯 王宏 朱丽华 陈芳 王楠 《大学化学》 CAS 2024年第4期149-156,共8页
碳捕集技术是实现“双碳”目标的重要途径。高温工业源CO_(2)的捕集更宜使用钙基吸收剂。本文立足“双碳”背景,将碳捕集前沿技术融入仪器分析实验课程,开发了蛋壳源CaO的制备、表征及其碳捕集性能的设计性综合实验。选择高钙废弃物鸡... 碳捕集技术是实现“双碳”目标的重要途径。高温工业源CO_(2)的捕集更宜使用钙基吸收剂。本文立足“双碳”背景,将碳捕集前沿技术融入仪器分析实验课程,开发了蛋壳源CaO的制备、表征及其碳捕集性能的设计性综合实验。选择高钙废弃物鸡蛋壳为原料,采用醋酸处理得到醋酸钙,再经高温煅烧制备了具有较好碳捕集性能的CaO;利用EDTA配位滴定、扫描电子显微镜、X射线衍射、红外光谱、拉曼光谱和热重分析等多种分析手段,测试了CaO的纯度、形貌、结构及其对CO_(2)的捕集性能。本实验采用项目式教学方式,引导学生自行设计实验方案并进行实践和总结,不仅锻炼了学生综合运用专业知识解决实际问题的能力,而且培养了学生的科研素养和团队合作精神。 展开更多
关键词 双碳 仪器分析实验 蛋壳 氧化钙 碳捕集
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Photocatalytic seawater splitting by 2D heterostructure of ZnIn_(2)S_(4)/WO_(3) decorated with plasmonic Au for hydrogen evolution under visible light
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作者 Huiqin An Yanjun wang +9 位作者 Xing Xiao Jiaxin Liu Zhiyao Ma Tianxin Gao Wanyu hong Lizhi Zhao hong wang Qingjun Zhu Shanshan Chen Zhen Yin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期55-63,I0003,共10页
Photocatalytic H_(2) evolution from seawater splitting presents a promising approach to tackle the fossil energy crisis and mitigate carbon emission due to the abundant source of seawater and sunlight on the earth.How... Photocatalytic H_(2) evolution from seawater splitting presents a promising approach to tackle the fossil energy crisis and mitigate carbon emission due to the abundant source of seawater and sunlight on the earth.However,the development of efficient photocatalysts for seawater splitting remains a formidable challenge.Herein,a 2D/2D ZnIn_(2)S_(4)/WO_(3)(ZIS/WO_(3))heterojunction nanostructure is fabricated to efficiently separate the photoinduced carriers by steering electron transfer from the conduction band minimum of WO_(3) to the valence band maximum of ZIS via constructing internal electric field.Subsequently,plasmonic Au nanoparticles(NPs)as a novel photosensitizer and a reduction cocatalyst are anchored on ZIS/WO_(3) surface to further enhance the optical absorption of ZIS/WO_(3) heterojunction and accelerate the catalytic conversion.The obtained Au/ZIS/WO_(3) photocatalyst exhibits an outstanding H_(2) evolution rate of 2610.6 or 3566.3μmol g^(-1)h~(-1)from seawater splitting under visible or full-spectrum light irradiation,respectively.These rates represent an impressive increase of approximately 7.3-and 6,6-fold compared to those of ZIS under the illumination of the same light source.The unique 2D/2D structure,internal electric field,and plasmonic metal modification together boost the photocatalytic H_(2) evolution rate of Au/ZIS/WO_(3),making it even comparable to H_(2) evolution from pure water splitting.The present work sheds light on the development of efficient photocatalysts for seawater splitting. 展开更多
关键词 Photocatalytic seawater splitting 2D/2D ZnIn_(2)S_(4)/WO_(3) Surface plasmon resonance effect Interfacial electric field
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Light-modulated graphene-based φ_(0) Josephson junction and -φ_(0) to φ_(0) transition
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作者 程任翔 于苗 +4 位作者 汪洪 曹德亮 李兴鳌 戚凤华 周兴飞 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期476-481,共6页
We investigate the chiral edge states-induced Josephson current–phase relation in a graphene-based Josephson junction modulated by the off-resonant circularly polarized light and the staggered sublattice potential.By... We investigate the chiral edge states-induced Josephson current–phase relation in a graphene-based Josephson junction modulated by the off-resonant circularly polarized light and the staggered sublattice potential.By solving the Bogoliubov–de Gennes equation,a φ_(0) Josephson junction is induced in the coaction of the off-resonant circularly polarized light and the staggered sublattice potential,which arises from the fact that the center of-mass wave vector of Cooper pair becomes finite and the opposite center of-mass wave vector to compensate is lacking in the nonsuperconducting region.Interestingly,when the direction of polarization of light is changed,-φ_(0) to φ_(0) transition generates,which generalizes the concept of traditional 0–πtransition.Our findings provide a purely optical way to manipulate a phase-controllable Josephson device and guidelines for future experiments to confirm the presence of graphene-based φ_(0)Josephson junction. 展开更多
关键词 GRAPHENE circularly polarized light staggered sublattice potential φ_(0)Josephson junction
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Extracorporeal membrane oxygenation versus cardiopulmonary bypass during transcatheter aortic valve implantation: a meta-analysis of survival benefits
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作者 Huiruo Liu Liangshan wang +4 位作者 Xing Hao Zhongtao Du Chenglong Li hong wang Xiaotong Hou 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第4期306-310,共5页
Since its approval by the Food and Drug Administration in 2011,transcatheter aortic valve implantation(TAVI)has rapidly evolved to become the preferred ultimate intervention for high-and intermediate-risk patients wit... Since its approval by the Food and Drug Administration in 2011,transcatheter aortic valve implantation(TAVI)has rapidly evolved to become the preferred ultimate intervention for high-and intermediate-risk patients with severe symptomatic aortic stenosis.[1]This is due to its non-open-heart,minimally invasive and off-pump advantages.[1]Nevertheless,as a result of the frequent frailty and comorbidity profiles of patients undergoing TAVI,such as advanced cardiac dysfunction and extensive coronary artery disease,or technically difficult anatomy for the procedure itself,[2-4]it is common for these patients to experience critical circulatory collapse perioperatively.These factors are linked to elevated mortality rates,necessitating suitable mechanical circulatory support(MCS)to reverse the disastrous situations.[5] 展开更多
关键词 ANATOMY BYPASS ELEVATED
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基于一流课程建设的分析化学实验教学改革与实践 被引量:11
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作者 陈芳 王宏 +2 位作者 刘敏 王楠 朱丽华 《大学化学》 CAS 2023年第5期26-30,共5页
分析化学是化学的四大基础课程之一,通常包含化学分析和仪器分析两门课程。我校自1983年建系以来即面向化学类专业开设了与理论课程向对应的分析化学(含仪器分析)实验课程。面向目前我校的化学和应用化学专业的学生,我们以精选教学内容... 分析化学是化学的四大基础课程之一,通常包含化学分析和仪器分析两门课程。我校自1983年建系以来即面向化学类专业开设了与理论课程向对应的分析化学(含仪器分析)实验课程。面向目前我校的化学和应用化学专业的学生,我们以精选教学内容、设计渐进式课程和采用多维度教学模式为主要改革方向,建设分析化学(含仪器分析)实验一流本科课程。 展开更多
关键词 分析化学实验 仪器分析实验 一流本科课程 课程建设
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经口内镜下肌切开术治疗贲门失弛缓症的初步研究(附27例报告) 被引量:4
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作者 李红平 王海波 +5 位作者 王玲 王红 刘黔 吴鸿 吴会超 庹必光 《中国内镜杂志》 北大核心 2017年第7期39-45,共7页
目的探讨经口内镜下肌切开术(POEM)治疗贲门失弛缓症(AC)的疗效。方法收集2014年5月-2016年3月遵义医学院附属医院消化内科收住入院的27例确诊为AC的患者,并实施POEM术,总结手术完成情况、手术前后临床症状、食管测压、术后并发症及随... 目的探讨经口内镜下肌切开术(POEM)治疗贲门失弛缓症(AC)的疗效。方法收集2014年5月-2016年3月遵义医学院附属医院消化内科收住入院的27例确诊为AC的患者,并实施POEM术,总结手术完成情况、手术前后临床症状、食管测压、术后并发症及随访过程等资料。结果 27例患者行POEM治疗的成功率为100.0%,1例患者发现皮下气肿,1例患者发现少量气胸,行POEM患者中随访症状较前明显改善,食管测压较前亦有显著变化(P<0.05)。结论 POEM治疗AC的短期疗效肯定,术后能够明显缓解吞咽困难等症,但其长期疗效及远期并发症仍有待进一步随访和观察。 展开更多
关键词 经口内镜下肌切开术 贲门失弛缓症 短期疗效
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石墨烯的绿色制备、表征及典型应用综合型实验 被引量:4
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作者 王楠 王芹 +3 位作者 王宏 陈芳 刘敏 朱丽华 《大学化学》 CAS 2023年第9期218-226,共9页
石墨烯具有优异的光电性能,在“碳中和”相关技术领域有巨大的应用潜力。最近,我们开发了一种采用过硫酸钾为磨剂机械化学制备边缘羟基化石墨烯的绿色新方法,产物兼具石墨烯本征性能佳和水中分散性好的特点;制备过程不需要使用有机溶剂... 石墨烯具有优异的光电性能,在“碳中和”相关技术领域有巨大的应用潜力。最近,我们开发了一种采用过硫酸钾为磨剂机械化学制备边缘羟基化石墨烯的绿色新方法,产物兼具石墨烯本征性能佳和水中分散性好的特点;制备过程不需要使用有机溶剂,能耗低,产生的废弃物量少且无毒。本文将该科研成果转化,设计了一个石墨烯的制备、表征及应用的综合型实验,利用多种仪器分析方法研究石墨烯的结构及光电性能,并与文献报道的研究结果进行了对比分析,不仅锻炼了学生综合运用知识解决实际问题的能力,而且有助于激发学生的创新思维,培养“绿色化学”意识。 展开更多
关键词 双碳 综合实验 绿色化学 石墨烯制备 仪器分析
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分析化学实验在线考试的实践 被引量:4
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作者 赵云斌 王宏 +3 位作者 刘敏 王楠 陈浩 吴康兵 《大学化学》 CAS 2021年第7期234-238,共5页
为了更好地发挥考试成绩在分析化学实验成绩评定中的作用,对分析化学实验考试模式进行了改革。根据课程培养目标和课程特点,建立高质量的试题库,利用互联网在线考试平台进行在线考试。与传统的分析化学实验笔试模式相比,分析化学实验在... 为了更好地发挥考试成绩在分析化学实验成绩评定中的作用,对分析化学实验考试模式进行了改革。根据课程培养目标和课程特点,建立高质量的试题库,利用互联网在线考试平台进行在线考试。与传统的分析化学实验笔试模式相比,分析化学实验在线考试具有简单、高效的优势。 展开更多
关键词 分析化学实验 试题库 在线考试
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手性导电高分子的应用进展 被引量:2
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作者 王红 贾庆明 陕绍云 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第5期171-178,共8页
手性导电高分子作为高分子一类新兴的分支,结合了手性分子和导电高分子的优点,具有独特的导电性、光学活性和手性,其种类丰富,应用领域广泛而成为研究热点。手性导电高分子具有4个结构特征:(ⅰ)主链中有共轭π-π~*键,具有离域效应;(ⅱ... 手性导电高分子作为高分子一类新兴的分支,结合了手性分子和导电高分子的优点,具有独特的导电性、光学活性和手性,其种类丰富,应用领域广泛而成为研究热点。手性导电高分子具有4个结构特征:(ⅰ)主链中有共轭π-π~*键,具有离域效应;(ⅱ)室温电导率可在绝缘体半导体金属态范围内变化;(ⅲ)可以掺杂和脱掺杂且完全可逆;(ⅳ)掺杂的实质是氧化还原反应,伴随着掺杂和脱掺杂有完全可逆的颜色变化。文中简要综述了模板法制备手性导电高分子,基于手性导电高分子现有的结构特征,深入分析了近十年来手性导电高分子在电学、磁学、化学和生物等领域的应用现状。 展开更多
关键词 手性导电高分子 模板法 结构特征 应用
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磁性纳米Fe_(3)O_(4)制备及在酵母RNA提取分析中的应用 被引量:2
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作者 王萍萍 李浩辰 +5 位作者 彭玉 罗小梦 朱丽华 王宏 陈芳 王楠 《大学化学》 CAS 2022年第6期91-101,共11页
磁珠法提取核酸是新冠病毒核酸检测的关键一环。基于此,以安全无毒的酵母RNA为对象,开发了一个涉及多学科化学知识交叉的综合实验,包括Fe_(3)O_(4)纳米磁珠制备与表征、RNA提取方法建立与机制探究、实际样品应用等。本实验既能锻炼学生... 磁珠法提取核酸是新冠病毒核酸检测的关键一环。基于此,以安全无毒的酵母RNA为对象,开发了一个涉及多学科化学知识交叉的综合实验,包括Fe_(3)O_(4)纳米磁珠制备与表征、RNA提取方法建立与机制探究、实际样品应用等。本实验既能锻炼学生综合运用化学知识和实验手段解决实际问题的能力,又能引导学生关注公共事件,培养其社会责任感。 展开更多
关键词 核酸提取 Fe_(3)O_(4) 酵母RNA FT-IR 紫外光度法
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雷珠单抗治疗视网膜静脉阻塞继发黄斑水肿的疗效及其影响因素 被引量:12
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作者 沈志军 王红 +1 位作者 陈蕊 李根林 《国际眼科杂志》 CAS 北大核心 2022年第10期1693-1697,共5页
目的:研究玻璃体腔注射雷珠单抗治疗视网膜静脉阻塞(RVO)继发黄斑水肿的疗效及其影响因素。方法:回顾性病例研究。收集2020-04/2021-02于我院治疗的RVO继发黄斑水肿患者61例61眼,其中BRVO患者30例30眼,CRVO患者31例31眼。所有患者均完成... 目的:研究玻璃体腔注射雷珠单抗治疗视网膜静脉阻塞(RVO)继发黄斑水肿的疗效及其影响因素。方法:回顾性病例研究。收集2020-04/2021-02于我院治疗的RVO继发黄斑水肿患者61例61眼,其中BRVO患者30例30眼,CRVO患者31例31眼。所有患者均完成了3次雷珠单抗(0.5mg)玻璃体腔注药治疗,部分患眼进行了视网膜激光治疗。治疗(首次玻璃体腔注药)后随访3mo,观察治疗后视力、眼压及黄斑中心凹厚度(CRT)情况,并记录眼部及全身并发症发生情况。结果:纳入患者治疗后视力均较治疗前显著改善,CRT均较治疗前显著降低(P<0.01),且BRVO和CRVO患者中治疗前视力≤1(LogMAR)的患者3次玻璃体腔注药后视力均优于治疗前视力>1的患者(P<0.01),但CRT无差异(均P>0.05)。BRVO和CRVO患者中分别有12、8眼在3次玻璃体腔注药期间进行了病变区激光治疗,BRVO和CRVO患者中激光治疗和未激光治疗的患者3次玻璃体腔注药后视力和CRT均无差异(P>0.05)。随访期间未发现眼部及全身严重并发症的发生。结论:雷珠单抗治疗RVO继发黄斑水肿具有良好的疗效和安全性,但基线视力可能对疗效具有一定影响。 展开更多
关键词 雷珠单抗 视网膜静脉阻塞 激光 黄斑水肿 疗效
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Black tea in chemo-prevention of cancer and other human diseases 被引量:20
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作者 Min-Hsiung Pan Ching-Shu Lai +3 位作者 hong wang Chih-Yu Lo Chi-Tang Ho Shiming Li 《Food Science and Human Wellness》 SCIE 2013年第1期12-21,共10页
Tea is the most popular functional beverage in the world and has been gaining more and more attention for its health beneficial properties.Among common teas,black tea is consumed more than green tea and oolong tea wor... Tea is the most popular functional beverage in the world and has been gaining more and more attention for its health beneficial properties.Among common teas,black tea is consumed more than green tea and oolong tea worldwide.Numerous studies have shown the biological activities of black tea and its polyphenols that include anti-oxidant,anti-tumor,anti-inflammation and metabolic regulation.Tea polyphenols such as theaflavins and catechins are considered to be multifunctional compounds that could be effective in the prevention or treatment of various cancers,cardiovascular disease,chronic inflammation,obesity,metabolic syndrome,and neurodegenerative diseases.In this review,we summarized the up-to-date research and underlying molecular mechanisms of black tea and its polyphenols.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. 展开更多
关键词 Black tea THEAFLAVINS CATECHINS Human disease Molecular mechanism CANCER
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PDR患者PPV术前行雷珠单抗注射对手术效果及并发症的影响 被引量:9
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作者 胡海涛 孙涛 +2 位作者 王红 吴华新 郝兰香 《国际眼科杂志》 CAS 北大核心 2019年第5期817-820,共4页
目的:探讨PDR患者行玻璃体切割术(PPV)前玻璃体内注射雷珠单抗对手术效果、并发症的影响。方法:选取我院2016-01/2018-01拟实施PPV手术的患者84例106眼,采用随机数字表法分为观察组和对照组,各42例,两组均采用PPV手术治疗,观察组术前给... 目的:探讨PDR患者行玻璃体切割术(PPV)前玻璃体内注射雷珠单抗对手术效果、并发症的影响。方法:选取我院2016-01/2018-01拟实施PPV手术的患者84例106眼,采用随机数字表法分为观察组和对照组,各42例,两组均采用PPV手术治疗,观察组术前给予雷珠单抗玻璃体注射治疗。对比两组患者手术前后的BCVA、黄斑中心凹厚度、血清VEGF、人生长停滞特异性蛋白6(GAS6)、人基质细胞衍生因子-1(SDF-1)、手术并发症。结果:术前两组BCVA无差异(P>0.05);术后3mo,观察组的BCVA显著优于对照组(P<0.05)。术后1wk,观察组的黄斑中心凹厚度小于对照组(P<0.05);术后3mo,两组的黄斑中心凹厚度无差异(P>0.05)。术前两组患者的血清VEGF、GAS6、SDF-1水平无差异(P<0.05);术后1wk,观察组的血清VEGF、GAS6、SDF-1水平低于对照组(P<0.05)。观察组的并发症率低于对照组(5.9%vs 20.0%,P<0.05)。结论:PDR患者行PPV前玻璃体内注射雷珠单抗能显著地降低黄斑厚度、血清VEGF、GAS6、SDF-1水平,提升手术后的视力,降低手术并发症发生率。 展开更多
关键词 增生型糖尿病视网膜病变 玻璃体切割术 雷珠单抗 并发症
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Perovskite LaFeO_3 supported bi-metal catalyst for syngas methanation 被引量:6
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作者 hong wang Yuzhen Fang +1 位作者 Yuan Liu Xue Bai 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第6期745-752,共8页
LaFeO3 perovskite supported Ni and Ni-Fe catalysts were prepared and applied to methanation reaction of syngas. Two preparation methods were employed. One was one-step citrate complexing method, and the other was a tw... LaFeO3 perovskite supported Ni and Ni-Fe catalysts were prepared and applied to methanation reaction of syngas. Two preparation methods were employed. One was one-step citrate complexing method, and the other was a two step method using citrate complexing method to produce LaFeO3 and followed by loading nickel oxide on it with impregnation. The structure evolution of the sample as prepared was investigated by XRD, TPR and TEM techniques. For the former, the chemical composites of the calcined sample are NiO-Fe2O3/LaFe1-xNixO3. After reduction and reaction of CO methanation, its composites convert to Fe-Ni@Ni/LaFeO3-La2O2CO3, in which Fe-Ni@Ni is metal particles in nano-size composed of nickel core and Fe-Ni alloy shell. For the latter, the chemical composites of the calcined sample are NiO/LaFeO3; and after reduction and reaction of CO methanation, its chemical composites change to Ni/LaFeO3. Ni/LaFeO3 catalyst is a little more active, while Fe-Ni@Ni/LaFeO3-La2O2CO3 is much more stable and shows very good resistance to carbon deposition. In this work it is aimed to show that the structure and composites of the catalysts can be tailored using perovskite-type oxide as precursor with different preparing method or preparing condition. Therefore, it is a promising route to prepare supported bi-metal catalysts in nano-size for a lot of metals with desired catalytic performances. 展开更多
关键词 PEROVSKITE bi-metal NICKEL IRON SYNGAS METHANATION
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Uplink Performance Analysis in Multi-Tier Heterogeneous Cellular Networks with Power Control and Biased User Association 被引量:5
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作者 Han Hu hong wang +1 位作者 Qi Zhu Ziyu Pan 《China Communications》 SCIE CSCD 2016年第12期25-36,共12页
A K-tier uplink heterogeneous cellular network is modelled and analysed by accounting for both truncated channel inversion power control and biased user association. Each user has a maximum transmit power constraint a... A K-tier uplink heterogeneous cellular network is modelled and analysed by accounting for both truncated channel inversion power control and biased user association. Each user has a maximum transmit power constraint and transmits data when it has sufficient transmit power to perform channel inversion. With biased user association, each user is associated with a base station(BS) that provides the maximum received power weighted by a bias factor, but not their nearest BS. Stochastic geometry is used to evaluate the performances of the proposed system model in terms of the outage probability and ergodic rate for each tier as functions of the biased and power control parameters. Simulations validate our analytical derivations. Numerical results show that there exists a trade-off introduced by the power cut-off threshold and the maximum user transmit power constraint. When the maximum user transmit power becomes a binding constraint, the overall performance is independent of BS densities. In addition, we have shown that it is beneficial for the outage and rate performances by optimizing different network parameters such as the power cut-off threshold as well as the biased factors. 展开更多
关键词 Heterogeneous cellular network uplink performance biased user association stochastic geometry
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A specific objective supplemental factor in evaluating acute mountain sickness: ΔHR in combination with SaO_2 被引量:7
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作者 Ming Li Ji-Hang Zhang +8 位作者 Guo-Xi Zhao Shi-Zhu Bian Xu-Bin Gao Xi Liu Jie Yu Jun-Qing Dong Guo-Zhu Chen hong wang Lan Huang 《Military Medical Research》 SCIE CAS 2015年第3期139-144,共6页
Background: So far, there have been no measurements confirmed useful in diagnosing acute mountain sickness(AMS). The aim of this study was to determine the role of heart rate(HR) difference(ΔHR) and oxygen saturation... Background: So far, there have been no measurements confirmed useful in diagnosing acute mountain sickness(AMS). The aim of this study was to determine the role of heart rate(HR) difference(ΔHR) and oxygen saturation(Sa O2) as objective risk factors in aiding the diagnosis of AMS.Methods: A total of 1,019 participants were assigned to either the acute exposure group(AEG): from 500 m to 3,700 m by flight within 2.5 hours(n=752); or the pre-acclimatization group(PAG): ascended to 4,400 m from 3,650 m within three hours by car after adapting 33 days at 3,650m(n=267). The questionnaires or measurements of resting Sa O2 and HR were completed between 18 and 24 hours before departure and after arrival.Results: Incidence of AMS was 61.3%(461) in AEG, with 46.1%(347) mild cases and 15.2%(114) severe cases. In PAG, the incidence was 38.9%(104), with 30.7%(82) mild cases and 8.2%(22) severe cases. The AMS subjects showed a significant increase in HR and a decrease in Sa O2 levels compared with the non-AMS subjects in both groups. ΔHR and post-exposure Sa O2 were significantly correlated with the Lake Louise Score(LLS) in both groups. Stepwise logistic regression analysis revealed the ΔHR >25 and Sa O2 <88% in AEG as well as ΔHR >15 and Sa O2 <86% in PAG to be independent risk factors of AMS. Combining these two measurements could specifically indicate participants with AMS, which showed a positive predictive value of 89% and specificity of 97% in AEG as well as 85% and 98% in PAG.Conclusion:ΔHR or Sa O2, as objective measurements, correlate with AMS. Combination of these two measurements may be useful as an additional specific and objective factor to further confirm the diagnosis of AMS. 展开更多
关键词 Acute mountain sickness Oxygen saturation Heart rate difference
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Response of soil respiration to a severe drought in Chinese Eucalyptus plantations 被引量:4
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作者 Shaojun wang hong wang 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第4期841-847,共7页
Extreme droughts can adversely affect the dynamics of soil respiration in tree plantations. We used a severe drought in southwestern China as a case study to estimate the effects of drought on temporal variations in s... Extreme droughts can adversely affect the dynamics of soil respiration in tree plantations. We used a severe drought in southwestern China as a case study to estimate the effects of drought on temporal variations in soil respiration in a plantation of Eucalyptus globulus. We documented a clear seasonal pattern in soil respiration with the highest values (100.9 mg C-CO2 m(-2) h(-1)) recorded in June and the lowest values (28.7 mg C-CO2 m(-2) h(-1)) in January. The variation in soil respiration was closely associated with the dynamics of soil water driven by the drought. Soil respiration was nearly twice as great in the wet seasons as in the dry seasons. Soil water content accounted for 83-91% of variation in soil respiration, while a combined soil water and soil temperature model explained 90-99% of the variation in soil respiration. Soil water had pronounced effects on soil respiration at the moisture threshold of 6-10%. Soil water was strongly related to changes in soil parameters (i.e., bulk density, pH, soil organic carbon, and available nitrogen). These strongly influenced seasonal variation in soil respiration. We found that soil respiration was strongly suppressed by severe drought. Drought resulted in a shortage of soil water which reduced formation of soil organic carbon, impacted soil acid-base properties and soil texture, and affected soil nutrient availability. 展开更多
关键词 DROUGHT Eucalyptus globulus Global change Soil respiration
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Engineering optimization approach of nonaqueous electrolyte for sodium ion battery with long cycle life and safety 被引量:4
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作者 Haiying Che Xinrong Yang +5 位作者 Yan Yu Chaoliang Pan hong wang Yonghong Deng Linsen Li Zi-Feng Ma 《Green Energy & Environment》 SCIE CSCD 2021年第2期212-219,共8页
Electrolyte design strategies are closely related to the capacities, cycle life and safety of sodium–ion batteries. In this study, we aimed to optimize electrolyte with the focus on engineering aspects. The basic phy... Electrolyte design strategies are closely related to the capacities, cycle life and safety of sodium–ion batteries. In this study, we aimed to optimize electrolyte with the focus on engineering aspects. The basic physicochemical properties including ionic conductivity, viscosity,wettability and thermochemical stability of the electrolytes using Na PF6 as the solute and the mixed solvent with different components of EMC,DMC or DEC in PC or EC were systematically measured. Ah pouch cell with NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)/hard carbon electrodes was used to evaluate the performance of the prepared electrolytes. By using the Inductive Coupled Plasma Emission Spectrometer(ICP), X-ray photoelectron spectroscopy(XPS), Thermogravimetric-differential scanning calorimetry(TG-DSC) and Accelerating Rate Calorimeter(ARC), we show that an optimized electrolyte can effectively promote the formation of a protective interfacial layer on two electrodes, which not only retards parasitic reactions between the electrodes and electrolyte but also suppresses dissolution of metal ions from the cathode. With an optimized electrolyte, a NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)/hard carbon cell can attain 56.16% capacity retention under the low temperature of -40℃, and can be able to retain 80%capacity retention after more than 2500 cycles while presenting excellent thermal safety. 展开更多
关键词 Sodium–ion battery NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2) Nonaqueous electrolyte SAFETY Engineering optimization
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Urban land-use impacts on composition and spatiotemporal variations in abundance and biomass of earthworm community 被引量:3
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作者 Jihang Li Zhe Zhang +2 位作者 hong wang Shaojun wang Qibo Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期325-331,共7页
Soil fauna can sensitively respond to alterations in soil environment induced by land-use changes.However,little is known about the impact of urban land-use changes on earthworm communities.In this study,three land-us... Soil fauna can sensitively respond to alterations in soil environment induced by land-use changes.However,little is known about the impact of urban land-use changes on earthworm communities.In this study,three land-use types(i.e.,forest,nursery and abandoned lands)were chosen to identify differences in diversity,abundance and biomass of earthworm community in Kunming City.Urban land-use had a pronounced difference in species composition,evenness and diversity of earthworm communities.Forest land had the highest density,biomass and diversity of the earthworm communities.Total abundance was dominated by endogeic species in nursery land(70%)and abandoned land(80%),whereas in the forest land,the earthworm community comprised epigeic,endogeic and anecic species.Temporal changes in earthworm density and biomass were also significantly affected by land-use change.Total density and biomass of earthworms in the forest and nursery lands were highest in September,but highest in the abandoned land in October.The influence of soil physicochemical properties on the earthworm density and biomass also varied with land-use types.Soil temperature significantly affected earthworm density and biomass in the three land-use types.Soil pH was positively correlated with earthworm biomass in the forest land,but negatively associated with earthworm density in the abandoned land.Soil organic matter was positively correlated only with density and biomass of earthworms in the nursery and abandoned lands.Our results suggest that the species composition,abundance and biomass of earthworm communities can be determined by the modification of soil properties associated with urban land-use type. 展开更多
关键词 BIOMASS Density Earthworm community Soil physicochemical properties Spatiotemporal dynamics
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