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Reversible solid-liquid conversion enabled by self-capture effect for stable non-flow zinc-bromine batteries 被引量:1
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作者 Xixi Zhang Xiaoke Wang +7 位作者 Guangmeng Qu Tairan Wang Xiliang Zhao Jun Fan Cuiping Han Xijin Xu Chunyi Zhi Hongfei Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第6期1035-1044,共10页
Non-flow aqueous zinc-bromine batteries without auxiliary components(e.g.,pumps,pipes,storage tanks)and ion-selective membranes represent a cost-effective and promising technology for large-scale energy storage.Unfort... Non-flow aqueous zinc-bromine batteries without auxiliary components(e.g.,pumps,pipes,storage tanks)and ion-selective membranes represent a cost-effective and promising technology for large-scale energy storage.Unfortunately,they generally suffer from serious diffusion and shuttle of polybromide(Br^(-),Br^(3-))due to the weak physical adsorption between soluble polybromide and host carbon materials,which results in low energy efficiency and poor cycling stability.Here,we develop a novel self-capture organic bromine material(1,10-bis[3-(trimethylammonio)propyl]-4,4'-bipyridinium bromine,NVBr4)to successfully realize reversible solid complexation of bromide components for stable non-flow zinc-bromine battery applications.The quaternary ammonium groups(NV^(4+)ions)can effectively capture the soluble polybromide species based on strong chemical interaction and realize reversible solid complexation confined within the porous electrodes,which transforms the conventional“liquid-liquid”conversion of soluble bromide components into“liquid-solid”model and effectively suppresses the shuttle effect.Thereby,the developed non-flow zinc-bromide battery provides an outstanding voltage platform at 1.7 V with a notable specific capacity of 325 mAh g^(-1)NVBr4(1 A g^(-1)),excellent rate capability(200 mAh g^(-1)NVBr4 at 20 A g^(-1)),outstanding energy density of 469.6 Wh kg^(-1)and super-stable cycle life(20,000 cycles with 100%Coulombic efficiency),which outperforms most of reported zinc-halogen batteries.Further mechanism analysis and DFT calculations demonstrate that the chemical interaction of quaternary ammonium groups and bromide species is the main reason for suppressing the shuttle effect.The developed strategy can be extended to other halogen batteries to obtain stable charge storage. 展开更多
关键词 Solid-liquid conversion Self-capture non-flow zinc-bromine batteries Quaternary ammonium
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Novel ternary metals-based telluride electrocatalyst with synergistic effects of high valence non-3d metal and oxophilic Te for pH-universal hydrogen evolution reaction 被引量:2
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作者 Seunghwan Jo Wenxiang Liu +5 位作者 Yanan Yue Ki Hoon Shin Keon Beom Lee Hyeonggeun Choi Bo Hou Jung Inn Sohn 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期736-743,I0015,共9页
Electrocatalyst designs based on oxophilic foreign atoms are considered a promising approach for developing efficient pH-universal hydrogen evolution reaction(HER)electrocatalysts by overcoming the sluggish alkaline H... Electrocatalyst designs based on oxophilic foreign atoms are considered a promising approach for developing efficient pH-universal hydrogen evolution reaction(HER)electrocatalysts by overcoming the sluggish alkaline HER kinetics.Here,we design ternary transition metals-based nickel telluride(Mo WNi Te)catalysts consisting of high valence non-3d Mo and W metals and oxophilic Te as a first demonstration of non-precious heterogeneous electrocatalysts following the bifunctional mechanism.The Mo WNi Te showed excellent HER catalytic performance with overpotentials of 72,125,and 182 mV to reach the current densities of 10,100,and 1000 mA cm^(-2),respectively,and the corresponding Tafel slope of 47,52,and 58 mV dec-1in alkaline media,which is much superior to commercial Pt/C.Additionally,the HER performance of Mo WNi Te is well maintained up to 3000 h at the current density of 100 mA cm^(-2).It is further demonstrated that the Mo WNi Te exhibits remarkable HER activities with an overpotential of 45 mV(31 mV)and Tafel slope of 60 mV dec-1(34 mV dec-1)at 10 mA cm^(-2)in neutral(acid)media.The superior HER performance of Mo WNi Te is attributed to the electronic structure modulation,inducing highly active low valence states by the incorporation of high valence non-3d transition metals.It is also attributed to the oxophilic effect of Te,accelerating water dissociation kinetics through a bifunctional catalytic mechanism in alkaline media.Density functional theory calculations further reveal that such synergistic effects lead to reduced free energy for an efficient water dissociation process,resulting in remarkable HER catalytic performances within universal pH environments. 展开更多
关键词 Telluride catalyst Oxophilic effect High valence non-3d metal Bifunctional mechanism pH-universal hydrogen evolution reaction
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LncRNA ZEB1-AS1和LncRNA SOX2OT在糖尿病肾病患者中的表达及与肾功能的相关性研究 被引量:1
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作者 何德娇 凌娜 +3 位作者 李正翔 乔玲 张淼淼 夏露 《疑难病杂志》 CAS 2024年第7期809-813,共5页
目的探究长链非编码RNA锌指E盒结合同源盒蛋白1反义链1(LncRNA ZEB1-AS1)和长链非编码RNA性别决定相关基因簇2重叠转录本(LncRNA SOX2OT)在糖尿病肾病(DN)患者中的表达及与肾功能的相关性。方法选取于2021年11月—2023年12月在武汉大学... 目的探究长链非编码RNA锌指E盒结合同源盒蛋白1反义链1(LncRNA ZEB1-AS1)和长链非编码RNA性别决定相关基因簇2重叠转录本(LncRNA SOX2OT)在糖尿病肾病(DN)患者中的表达及与肾功能的相关性。方法选取于2021年11月—2023年12月在武汉大学人民医院肾内科收治的DN患者106例为DN组,并根据24 h尿蛋白定量(24 h Upro)水平分为正常蛋白尿亚组43例(<30 mg)、微量蛋白尿亚组39例(30~<300 mg)、大量蛋白尿亚组24例(≥300 mg),另选取同期医院单纯糖尿病患者106例作对照组,检测患者血清LncRNA ZEB1-AS1、LncRNA SOX2OT水平;Pearson法分析LncRNA ZEB1-AS1和LncRNA SOX2OT与肾功能指标的相关性;Logistic分析影响DN患者肾功能损伤的因素。结果DN组血清LncRNA ZEB1-AS1、LncRNA SOX2OT水平低于对照组(t=11.471、10.257,P均<0.001)。血清LncRNA ZEB1-AS1、LncRNA SOX2OT比较,正常尿蛋白亚组>微量尿蛋白亚组>大量尿蛋白亚组(F=58.720、117.722,P均<0.001),BUN、SCr、UA水平比较,正常尿蛋白亚组<微量尿蛋白亚组<大量尿蛋白亚组,差异均有统计学意义(F=122.493、595.589、53.178,P均<0.001);LncRNA ZEB1-AS1、LncRNA SOX2OT分别与BUN、SCr、UA呈负相关(r=-0.487、-0.498、-0.521,-0.527、-0.515、-0.534,P均<0.001);Logistic回归分析显示,糖尿病病程长及高BUN、SCr、UA水平是影响DN患者肾功能损伤的危险因素[OR(95%CI)=1.672(1.128~2.479)、2.839(1.534~5.253)、2.754(1.512~5.017)、2.693(1.464~4.954)],高LncRNA ZEB1-AS1、LncRNA SOX2OT是保护因素[OR(95%CI)=0.875(0.798~0.959)、0.898(0.832~0.969)]。结论血清LncRNA ZEB1-AS1、LncRNA SOX2OT水平与DN患者肾功能有关,可能是评估DN患者肾功能的潜在指标。 展开更多
关键词 糖尿病肾病 长链非编码RNA锌指E盒结合同源盒蛋白1反义链1 长链非编码RNA性别决定相关基因簇2重叠转录本 肾功能 相关性
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双手性金属协同催化立体发散性合成非天然α-氨基酸
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作者 王少华 《西北师范大学学报(自然科学版)》 CAS 2024年第6期1-3,27,I0002,共5页
手性非天然α-氨基酸广泛存在于天然产物和生物活性分子中,一直以来都是有机化学的研究热点.另外,烯烃合成过程中碳-碳双键的Z和E构型的精确控制是合成化学中的一个重要挑战.文中介绍了张万斌和麻生明团队近期在非天然α-氨基酸不对称... 手性非天然α-氨基酸广泛存在于天然产物和生物活性分子中,一直以来都是有机化学的研究热点.另外,烯烃合成过程中碳-碳双键的Z和E构型的精确控制是合成化学中的一个重要挑战.文中介绍了张万斌和麻生明团队近期在非天然α-氨基酸不对称合成领域中的一个亮点工作,通过双手性金属协同催化策略,实现了具有三取代烯烃结构的非天然α-氨基酸的立体发散性合成,反应收率高,对映选择性和Z/E选择性好,为药物设计和蛋白质修饰提供了更多的选择. 展开更多
关键词 非天然α-氨基酸 Z/E选择性 立体发散性合成 双手性金属协同催化
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Characteristics and risk of violation behavior of non-motorists at signalized intersections 被引量:6
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作者 赵星 任刚 +2 位作者 杜轩 王鹏 王卫杰 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期423-429,共7页
Aiming at prevalent violations of non-motorists at urban intersections in China, this paper intends to clarify the characteristics and risks of non-motorist violations at signalized intersections through questionnaire... Aiming at prevalent violations of non-motorists at urban intersections in China, this paper intends to clarify the characteristics and risks of non-motorist violations at signalized intersections through questionnaires and video recordings, which may serve as a basis for non-motorized vehicle management. It can help improve the traffic order and enhance the degree of safety at signalized intersections. To obtain the perception information, a questionaire survey on the Internet was conducted and 972 valid questionnaires were returned. It is found that academic degree contributes little to non-motorist violations, while electrical bicyclists have a relatively higher frequency of violations compared with bicyclists. The video data of 18 228 non-motorist behaviors indicate that the violation rate of all non-motorists is 26.5%; the number of conflicts reaches 1 938, among which violation conflicts account for 66.8%. The study shows that the violation rates and the violation behavior at three types of surveyed intersections are markedly different. It is also concluded that the conflict rates and the violation rates are positively correlated. Furthermore, signal violation, traveling in the wrong direction, and overspeeding to cross the intersection are the most dangerous among traffic violation behaviors. 展开更多
关键词 traffic violation behavior traffic safety non- motorist signal intersection
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月球样品的中子活化分析技术研究 被引量:9
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作者 姚永刚 肖才锦 +4 位作者 李玉庆 焦学胜 孙凯 郭冰 陈东风 《中国无机分析化学》 CAS 北大核心 2024年第1期93-103,共11页
月球的起源是月球研究的核心问题。月球探测任务返回的数据和样品极大地提高了人类对地月系统的认知,同时也发现了更多未解之谜,亟待未来的探测任务和科学研究来解答。嫦娥五号月壤是我国首次地外天体采集返回的样品,也是继美国和苏联... 月球的起源是月球研究的核心问题。月球探测任务返回的数据和样品极大地提高了人类对地月系统的认知,同时也发现了更多未解之谜,亟待未来的探测任务和科学研究来解答。嫦娥五号月壤是我国首次地外天体采集返回的样品,也是继美国和苏联探月采样任务45年后人类再次获得的月球样品。鉴于月球样品的珍贵性和特殊性,利用先进技术开展其全元素含量的非破坏精准分析对于认识月球演化和月球资源就地开发利用具有重要的意义。依托大型核反应研究堆和加速器中子注量率优势,利用中子活化分析技术可实现月球样品中的全元素非破坏分析:1)仪器中子活化分析技术(INAA)可测量Na—U元素之间的60余种元素;2)瞬发γ中子活化分析技术(PGNAA)可补充测量INAA不适合测量的元素如H、B、C、N等;3)中子深度剖面分析技术(NDP)可测量样品近表面(微米级)聚变能源3He的浓度深度分布;4)缓发中子测量技术(DNC)可定量样品中痕量裂变核素如^(235)U和^(239)Pu,并结合INAA可测量238U/235U同位素比值;5)14 MeV快中子活化分析技术(FNAA)可测量INAA和PGNAA不灵敏或不适合测量的元素如O、Si、P等。因此,中子活化分析技术(NAA)可有效解决月球样品中全元素、非破坏和精准测量问题,为我国深空探测珍贵样品研究提供核分析技术支撑。 展开更多
关键词 嫦娥五号月壤 月球陨石 中子活化分析 非破坏分析 深空探测
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基于改进组合赋权法和VIKOR法的茄芯烟叶化学品质评价
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作者 张勇刚 任志广 +2 位作者 刘建国 赵程虹 李奇 《西南农业学报》 CSCD 北大核心 2024年第7期1488-1493,共6页
[目的]探讨改进组合赋权法与多准则妥协解排序法(VIKOR)相结合开展茄芯化学品质评价,以期丰富雪茄烟叶质量评价方法。[方法]以云南茄芯烟叶化学成分为研究对象,引入变异系数和复相关系数改进传统CRITIC法(Criteria importance through i... [目的]探讨改进组合赋权法与多准则妥协解排序法(VIKOR)相结合开展茄芯化学品质评价,以期丰富雪茄烟叶质量评价方法。[方法]以云南茄芯烟叶化学成分为研究对象,引入变异系数和复相关系数改进传统CRITIC法(Criteria importance through inter-criteria correlation),采用e^(0/4)~e^(8/4)标度取代层次分析法(Analytic hierarchy process,AHP)中的1~9标度,并基于博弈论计算组合权重,利用无权重个体遗憾值改进的VIKOR法开展茄芯化学品质评价。[结果]与传统CRITIC法确定的化学成分指标权重相比,改进CRITIC法中钾的权重提升1.09倍,还原糖指标权重降低45.26%;e^(0/4)~e^(8/4)标度与1~9标度AHP法确权结果相比,权重大小排序一致,不同化学成分指标间权重的差异减小;改进VIKOR法与传统方法对茄芯化学品质的排序结果具有较高的一致性,但也存在不可忽略的差异,说明有必要在个体遗憾值中考虑权重的影响。[结论]改进CRITIC法能够解决传统方法确权受计量单位和正负向指标影响的问题,AHP法中通过标度的替代显著提升判断矩阵的一致性,无权重个体遗憾值条件下的VIKOR法在综合考虑化学品质整体表现的同时,突显了表现较差的化学成分指标的作用,评价结果相对合理。 展开更多
关键词 茄芯 复相关系数 e^(0/4)~e^(8/4)标度 CRITIC VIKOR 无权重个体遗憾值
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Modified streptozotocin-induced diabetic model in rodents
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作者 Anton Lennikov Farris ElZaridi Menglu Yang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第5期777-780,共4页
Streptozotocin(STZ)-induced type I diabetes mellitus(DM)models have been pivotal in diabetes research due to their ability to mimic the insulin-dependent hyperglyce-mia akin to human type I diabetes.However,these mode... Streptozotocin(STZ)-induced type I diabetes mellitus(DM)models have been pivotal in diabetes research due to their ability to mimic the insulin-dependent hyperglyce-mia akin to human type I diabetes.However,these models often suffer from poor induction rates and low survival post-STZ induction,especially in long-term experi-ments,necessitating insulin supplementation,which introduces additional variables to experiments.To address this,we present a novel modification to the STZ-induced DM model in C57BL/6J mice to improve survival rates without insulin supplemen-tation.Our method involves non-fasting,low-dose STZ injections dissolved in pH-neutral phosphate buffer saline instead of acidic sodium citrate buffer,administered over 5 days.We observed hyperglycemia induction in 94.28%of mice within a week post-injection,with stable high blood glucose levels,stable body weight,and minimal mortality up to 21 weeks.Notably,omitting 10%sucrose in water and fasting did not affect hyperglycemia induction.Our findings suggest that the modified protocol not only decreases the experimental effort of the researchers,but reduces animal stress and mortality,thus enhancing experimental outcomes and animal welfare.By opti-mizing the STZ-induced DM model in C57BL/6J mice,our study provides a valuable resource for researchers aiming to study diabetes and its complications while mini-mizing experimental variability and animal usage. 展开更多
关键词 HYPERGLYCEMIA non- FASTING STREPTOZOTOCIN Type 1 diabetes mellitus
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直播电商中的不标准现象分析及标准体系构建
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作者 代婷 刘世新 《标准科学》 2024年第5期24-29,共6页
直播电商发展如火如荼,成为刺激消费、拉动经济增长及创新创业的新引擎,对我国释放双循环发展活力影响显著,但急速发展的背后乱象丛生,亟需从标准化的视角对直播电商进行规范管理。结合直播电商的现有法律法规、标准,从平台、商户服务... 直播电商发展如火如荼,成为刺激消费、拉动经济增长及创新创业的新引擎,对我国释放双循环发展活力影响显著,但急速发展的背后乱象丛生,亟需从标准化的视角对直播电商进行规范管理。结合直播电商的现有法律法规、标准,从平台、商户服务、主播、基础设施4个方面对直播电商中的不标准现象进行归纳。结合不标准现象及顾客需求,构建直播电商标准体系,为直播电商的良性发展提供参考。 展开更多
关键词 直播电商 不标准现象 标准体系
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长链非编码RNA LINC00261通过调控miR-324-3p/EST1促进胃癌进展
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作者 谢锐 尹源 +1 位作者 滕俊 梁红亮 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第10期2101-2107,共7页
目的:探讨长链非编码RNA LINC00261通过干扰miR-324-3p表达调控E26转录因子1(EST1)水平促进胃癌(GC)的进展。方法:收集2018年6月至2020年10月在三六三医院接受手术治疗的GC患者(n=80)的癌组织及其相应癌旁正常组织作为研究样本,qRT-PCR... 目的:探讨长链非编码RNA LINC00261通过干扰miR-324-3p表达调控E26转录因子1(EST1)水平促进胃癌(GC)的进展。方法:收集2018年6月至2020年10月在三六三医院接受手术治疗的GC患者(n=80)的癌组织及其相应癌旁正常组织作为研究样本,qRT-PCR检测LINC00261和miR-324-3p表达水平。分析LINC00261与临床病理参数之间的相关性。将siRNA(si-LINC00261)、miRNA模拟物(miR-324-3p)和miRNA抑制剂(miR-324-3p in)及其相应对照转染至MGC-803和SGC-7901细胞;克隆形成试验评估细胞增殖能力;Transwell试验评估细胞迁移和侵袭能力;Western blot检测E-cadherin、N-cadherin和ETS1蛋白表达水平;肿瘤异种移植实验检测LINC00261在体内的肿瘤形成能力;荧光素酶报告、RNA沉淀分析LINC00261、miR-324-3p及EST1之间的作用关系。结果:与癌旁组织相比,GC组织中LINC00261表达明显上调,差异具有统计学意义(P<0.05)。LINC00261表达与患者TNM分期、组织分化程度淋巴结转移及微血管侵犯有关(P<0.05);通过数据库预测、萤火虫荧光素酶实验及RNA免疫沉淀结果显示,LINC00261和miR-324-3p存在靶向作用关系;GC组织中miR-324-3p水平明显低于癌旁正常组织(P<0.05);miR-324-3p水平与LINC00261表达呈负相关(P<0.05);与in NC+si-NC组相比,in NC+si-LINC00261组细胞增殖、迁移和侵袭能力及N-cadherin表达明显被抑制(P<0.05),E-cadherin表达明显升高(P<0.05);与in NC+si-LINC00261组相比,siLINC00261+miR-324-3p in组细胞增殖、迁移和侵袭能力及N-cadherin表达明显提高(P<0.05),E-cadherin表达明显降低(P<0.05),Targetscan预测及萤火虫荧光素酶实验表明ETS1是miR-324-3p的下游结合位点;转染miR-324-3p后,ETS1蛋白水平显著下调(P<0.05),但转染miR-324-3p in后,ETS1蛋白水平显著上调(P<0.05);在GC组织中ETS1表达明显高于癌旁正常组织(P<0.05);miR-324-3p水平与ETS1呈负相关(P<0.05);转染si-LINC00261的MGC-803细胞产生的肿瘤重量低于转染siNC的MGC-803细胞产生的肿瘤重量(P<0.05),在si-LINC00261来源的肿瘤中,ETS1的蛋白水平低于si-NC来源的肿瘤(P<0.05)。结论:LINC00261在GC组织中高表达,其可能通过调控miR-324-3p影响EST1表达促进GC进展。 展开更多
关键词 胃癌 侵袭 增殖 长链非编码RNA LINC00261 E26转录因子1
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非营养性吸吮在喂养不耐受早产儿中的应用 被引量:1
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作者 江静霞 皇敏 +2 位作者 伍静梅 徐梅影 陈媚 《妇儿健康导刊》 2024年第8期41-44,共4页
目的探讨非营养性吸吮在喂养不耐受早产儿中的应用。方法选取2021年11月至2022年4月深圳市龙华区人民医院收治的120例喂养不耐受早产儿,按照随机数字表法分为观察组和对照组,每组60例。对照组实施口胃管喂养,观察组在对照组基础上给予... 目的探讨非营养性吸吮在喂养不耐受早产儿中的应用。方法选取2021年11月至2022年4月深圳市龙华区人民医院收治的120例喂养不耐受早产儿,按照随机数字表法分为观察组和对照组,每组60例。对照组实施口胃管喂养,观察组在对照组基础上给予非营养性吸吮,比较两组的干预效果。结果观察组腹胀、胃潴留、呕吐发生率低于对照组,差异有统计学意义(P<0.05);观察组日增奶量优于对照组,体重恢复时间、住院时间、胃肠道喂养时间均短于对照组,差异有统计学意义(P<0.05);干预前,两组胃泌素(GAS)、胃动素(MOT)水平比较,差异无统计学意义(P>0.05);两组出生后3、7d的GAS、MOT水平均高于干预前,且观察组GAS、MOT水平均高于对照组,差异有统计学意义(P<0.05)。结论非营养性吸吮能够改善喂养不耐受早产儿的喂养情况,促进生长发育,增强消化系统功能,值得推广。 展开更多
关键词 非营养性吸吮 喂养不耐受早产儿 胃泌素 胃动素
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Alkylpolyglycoside inducing poly (butylene terephthalate) non-woven graft copolymerization of chitosan
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作者 陈叶廷 施婷婷 +4 位作者 祁姗姗 杨牧 孟娜 龚祝南 黄斌 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期474-479,共6页
In order to improve the wettability and biocompatibility of the poly (butylene terephthalate) non-woven (PBTNW), the method of surface modification is used to graft copolymerization of chitosan (CS) onto the PBT... In order to improve the wettability and biocompatibility of the poly (butylene terephthalate) non-woven (PBTNW), the method of surface modification is used to graft copolymerization of chitosan (CS) onto the PBTNW under alkylpolyglycoside (APG) inducing. The product is thoroughly characterized with the Fourier transform infrared spectroscopy (FrIR), the electron spectroscopy for chemical analysis (ESCA), the thermogravimetric (TG) and the scanning electron microscopy (SEM). It is found that chitosan is successfully grafted onto PBTNW. In addition, the water contact angles, hemolysis tests and cytotoxicity evaluation tests show an improvement in wettability and biocompatihility as a result of graft copolymerization of chitosan. So the CS-grafted PBTNW exhibits greater superiority than the original PBTNW. The CS-grafted PBTNW can be a candidate for blood filter materials and other medical applications. 展开更多
关键词 CHITOSAN GRAFT poly (butylene terephthalate) non- woven alkylpolyglycoside BIOCOMPATIBILITY WETTABILITY
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Optimal Design of Multiple Stress Constant Accelerated Life Test Plan on Non-rectangle Test Region 被引量:8
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作者 CHEN Wenhua GAO Liang +2 位作者 LIU Juan QIAN Ping PAN Jun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1231-1237,共7页
For optimal design of constant stress accelerated life test(CSALT) with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT desig... For optimal design of constant stress accelerated life test(CSALT) with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT design on non-rectangle test region, the present method is only focused on non-rectangle test region with simple boundary, and the optimization algorithm is based on experience which can not ensure to obtain the optimal plan. In this paper, considering the linear-extreme value model and the optimization goal to minimize the variance of lifetime estimate under normal stress, the optimal design method of two-stress type-I censored CSALT plan on general non-rectangular test region is proposed. First, two properties of optimal test plans are proved and the relationship of all the optimal test plans is determined analytically. Then, on the basis of the two properties, the optimal problem is simplified and the optimal design method of two-stress CSALT plan on general non-rectangular test region is proposed. Finally, a numerical example is used to illustrate the feasibility and effectiveness of the method, The result shows that the proposed method could obtain the optimal test plan on non-rectangular test regions with arbitrary boundaries. This research provides the theory and method for two-stress optimal CSALT planning on non-rectangular test regions. 展开更多
关键词 accelerated life test non- rectangular test region test plan optimal design
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Use of non-selective beta blockers in cirrhosis:The evidence we need before closing(or not) the window 被引量:4
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作者 Vincenzo La Mura Giulia Tosetti +1 位作者 Massimo Primignani Francesco Salerno 《World Journal of Gastroenterology》 SCIE CAS 2015年第8期2265-2268,共4页
Non selective beta blockers(NSBBs)are used in primary and secondary prophylaxis of portal hypertensionrelated bleeding in patients with cirrhosis.The efficacy of NSBBs treatment is predicted by hemodynamic response in... Non selective beta blockers(NSBBs)are used in primary and secondary prophylaxis of portal hypertensionrelated bleeding in patients with cirrhosis.The efficacy of NSBBs treatment is predicted by hemodynamic response in term of reduction of the hepatic venouspressure gradient(HVPG)below 12 mm Hg or at least20%of the basal value.Nevertheless a relevant number of patients who do not achieve this HVPG reduction during NSBBs therapy do not bleed during follow up;this evidence suggests an additional non-hemodynamic advantage of NSBBs treatment to modify the natural history of cirrhosis.Recent studies have questioned the efficacy and safety of NSBBs in patients with advanced stage of liver disease characterized by refractory ascites and/or spontaneous bacterial peritonitis.These studies have suggested the existence of a defined and limited period to modify the natural history of cirrhosis by NSBBs:the"window hypothesis".According with this hypothesis,patients with cirrhosis benefit from the use of NSBBs from the appearance of varices up to the development of an advanced stage of cirrhosis.Indeed,in patients with refractory ascites and/or spontaneous bacterial peritonitis the hemodynamic effects of NSBBs may expose to a high risk of further complications such as renal insufficiency and/or death.Methodological concerns and contrasting results counterbalance the evidence produced up to now on this issue and are the main topic of this editorial. 展开更多
关键词 BLEEDING PROPHYLAXIS End stage liver disease non-s
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2022年重庆市巴南区成人烟草使用监测结果分析
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作者 杨笑语 潘冬梅 +1 位作者 陈鹏 苏耀 《黑龙江科学》 2024年第17期32-34,共3页
为了解2022年重庆市巴南区成人烟草使用现状,分析相关影响因素,为控烟策略或政策的有效制定与改进提供科学依据,结合多阶段分层整群随机抽样法、PPS抽样调研法及简单随机抽样法对重庆市巴南区居民进行调查,统计其人口学特征、吸烟率、... 为了解2022年重庆市巴南区成人烟草使用现状,分析相关影响因素,为控烟策略或政策的有效制定与改进提供科学依据,结合多阶段分层整群随机抽样法、PPS抽样调研法及简单随机抽样法对重庆市巴南区居民进行调查,统计其人口学特征、吸烟率、戒烟率、电子烟知晓率、非吸烟者二手烟暴露率等信息。调查结果显示,巴南区居民吸烟率为19.35%,不同性别间的差异具有统计学意义,性别是影响巴南区居民吸烟率的主要因素。非吸烟者二手烟暴露率为34.67%,不同年龄、文化程度及城乡间的差异具有统计学意义。吸烟率与非吸烟者二手烟暴露率均显著低于2020年监测指标及国内平均水平。戒烟率及电子烟知晓率分别为24.38%、39.8%,不同年龄、文化程度受访者的电子烟知晓率差异具有统计学意义。基于此,应加强宣传,完善相关法律法规,完善戒烟服务体系,从而使居民有效控烟戒烟。 展开更多
关键词 烟草监测 吸烟率 二手烟暴露率 戒烟率 电子烟知晓率
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Moxifloxacin-containing triple therapy after non-bismuth quadruple therapy failure for Helicobacter pylori infection 被引量:2
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作者 Ji Hyun Lim Dong Ho Lee +4 位作者 Seong Tae Lee Nayoung Kim Young Soo Park Cheol Min Shin In Sung Song 《World Journal of Gastroenterology》 SCIE CAS 2015年第46期13124-13131,共8页
AIM: To assess the efficacy of moxifloxacin-containing triple therapy after non-bismuth quadruple therapy failure for Helicobacter pylori(H. pylori) eradication.METHODS: Between January 2010 and December 2012,we scree... AIM: To assess the efficacy of moxifloxacin-containing triple therapy after non-bismuth quadruple therapy failure for Helicobacter pylori(H. pylori) eradication.METHODS: Between January 2010 and December 2012,we screened individuals who were prescribed non-bismuth quadruple therapy for H. pylori eradication. Among them,a total of 98 patients who failed non-bismuth quadruple therapy received 1-wk or 2-wk moxifloxacin-containing triple therapy(400 mg moxifloxacin once daily,and 20 mg of rabeprazole and 1 g of amoxicillin twice daily). H. pylori status was evaluated using the 13C-urea breath test 4 wk later,after treatment completion. The eradication rates were determined by intention-to-treat and per-protocol analyses.RESULTS: In total,60 and 38 patients received 1-wk and 2-wk moxifloxacin-containing triple therapy,respectively. The intention-to-treat and per-protocol eradication rates were 56.7%(95%CI: 45.0-70.0) and 59.6%(95%CI: 46.6-71.7) in the 1-wk group and 76.3%(95%CI: 63.2-89.5) and 80.6%(95%CI: 66.7-91.9) in the 2-wk group(P = 0.048 and 0.036,respectively). All groups had good compliance(95% vs 94.9%). Neither group showed serious adverse events,and the proportions of patients experiencing mild side effects were not significantly different(21.1% vs 13.9%). Clinical factors such as age,sex,alcohol and smoking habits,comorbidities,and presence of gastric or duodenal ulcer did not influence the eradication therapy efficacy. The efficacy of second-line eradication therapy did not differ significantly according to the firstline regimen.CONCLUSION: Two-week moxifloxacin-containing triple therapy showed better efficacy than a 1-wk regimen after non-bismuth quadruple therapy failure.Key words: Helicobacter pylori; Moxifloxacin-based triple; Non-bismuth quadruple; Second-line; 展开更多
关键词 HELICOBACTER PYLORI Moxifloxacin-based triple non-
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N-acetylcysteine attenuates oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis 被引量:2
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作者 Duangporn Thong-Ngam Suchittra Samuhasaneeto +1 位作者 Onanong Kulaputana Naruemon Klaikeaw 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第38期5127-5132,共6页
AIM: To evaluate attenuating properties of N-acetylcysteine (NAC) on oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis (NASH). METHODS: Male Sprague-Dawley rats were randomly divided into... AIM: To evaluate attenuating properties of N-acetylcysteine (NAC) on oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis (NASH). METHODS: Male Sprague-Dawley rats were randomly divided into three groups. Group 1 (control, n = 8) was free accessed to regular dry rat chow (RC) for 6 wk. Group 2 (NASH, n = 8) was fed with 100% fat diet for 6 wk. Group 3 (NASH + NAC20, n = 9) was fed with 100% fat diet plus 20 mg/kg per day of NAC orally for 6 wk. All rats were sacrificed to collect blood and liver samples at the end of the study. RESULTS: The levels of total glutathione (GSH) and hepatic malondialdehyde (MDA) were increased significantly in the NASH group as compared with the control group (GSH; 2066.7 ± 93.2 vs 1337.5 ± 31.5 μmol/L and MDA; 209.9± 43.9 vs 3.8 ±1.7 μmol/g protein, respectively, P < 0.05). Liver histopathology from group 2 showed moderate to severe macrovesicular steatosis, hepatocyte ballooning, and necroinflammation. NAC treatment improved the level of GSH (1394.8 ± 81.2 μmol/L, P < 0.05), it did not affect MDA (150.1 ± 27.0 μmol/g protein), but led to a decrease in fat deposition and necroinflammation. CONCLUSION: NAC treatment could attenuate oxidative stress and improve liver histology in rats with NASH. 展开更多
关键词 N-ACETYLCYSTEINE Oxidative stress non- alcoholic steatohepatitis
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Non-3GPP对EPS的安全接入研究 被引量:1
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作者 杜雪涛 袁捷 +1 位作者 吴晓岩 张振涛 《电信工程技术与标准化》 2009年第7期11-15,共5页
Non-3GPP网络安全接入EPS是未来异构网络融合的重要基础。本文介绍了Non-3GPP网络接入时EPS系统的安全架构、可信的Non-3GPP网络接入EPS系统的认证机制、密钥协商流程等。
关键词 安全接入 non-3GPP EPS认证密钥协商
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Non-Markovian dynamics of a qubit in a reservoir: different solutions of non-Markovian master equation 被引量:1
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作者 丁邦福 王小云 +2 位作者 唐艳芳 米贤武 赵鹤平 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期25-29,共5页
We present a non-Markovian master equation for a qubit interacting with a general reservoir, which is derived according to the Nakajima-Zwanzig and the time convolutionless projection operator technique. The non-Marko... We present a non-Markovian master equation for a qubit interacting with a general reservoir, which is derived according to the Nakajima-Zwanzig and the time convolutionless projection operator technique. The non-Markovian solutions and Markovian solution of dynamical decay of a qubit are compared. The results indicate the validity of non-Markovian approach in different coupling regimes and also show that the Markovian master equation may not precisely describe the dynamics of an open quantum system in some situation. The non-Markovian solutions may be effective for many qubits independently interacting with the heated reservoirs. 展开更多
关键词 Nakajima-Zwanzig and time convolutionless projection operator technique non- Markovian solutions Markovian solutions correlation function QUBIT
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Tunnelling effect of the non-stationary Kerr black hole 被引量:1
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作者 杨树政 陈德友 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期817-821,共5页
Extending Parikh and Wilczek's work to the non-stationary black hole, we study the Hawking radiation of the non-stationary Kerr black hole by the Hamilto-Jacobi method. The result shows that the radiation spectrum is... Extending Parikh and Wilczek's work to the non-stationary black hole, we study the Hawking radiation of the non-stationary Kerr black hole by the Hamilto-Jacobi method. The result shows that the radiation spectrum is not purely thermal and the tunnelling probability is related to the change of Bekenstein Hawking entropy, which gives a correction to the Hawking thermal radiation of the black hole. 展开更多
关键词 Hamilton-Jacobi equation radiation spectrum self-gravitation interaction non- stationary Kerr black hole
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