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TPS-PBAT复合材料的制备及表征

塑料科技 2024年第5期52卷 117-120页

作者：姜林旭王晓广夏发明方可苏小雅武汉纺织大学湖北武汉430200 湖北顶新环保生物质材料有限公司湖北黄石435200 山东润泉生物科技有限公司山东枣庄277000

以钠基蒙脱土为填充物制备Na-GMMT/TPS粒料(简称TPS),将TPS按不同比例与PBAT共混,通过双螺杆挤出机制备TPS-PBAT复合材料。通过万能材料试验机、X射线衍射系统(XRD)、热重分析仪(TG)和扫描电子显微镜(SEM),对TPS-PBAT复合材料的结构和... 详细信息

以钠基蒙脱土为填充物制备Na-GMMT/TPS粒料(简称TPS),将TPS按不同比例与PBAT共混,通过双螺杆挤出机制备TPS-PBAT复合材料。通过万能材料试验机、X射线衍射系统(XRD)、热重分析仪(TG)和扫描电子显微镜(SEM),对TPS-PBAT复合材料的结构和性能进行表征。结果表明:以TPS为基体时,复合材料可以在保持良好断裂伸长率的前提下,大幅提升拉伸强度。TPS-PBAT-4复合材料的断裂伸长率为233.3%,拉伸强度为18.9 MPa。随着TPS含量的提升,复合材料的衍射峰逐渐平缓,说明TPS的添加降低了复合材料的结晶度。TPS的加入,提升了玉米淀粉和PBAT的热稳定性。以PBAT为基体时,TPS与PBAT的相容性较差。以TPS为基体时,TPS与PBAT之间没有明显的界限,表现出较好的相容性。

关键词：钠基蒙脱土 TPS PBAT 力学性能

拟南芥转录因子HAT1负调控盐胁迫分子机制研究

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广州大学学报（自然科学版） 2024年第2期23卷 13-25页

作者：方可李佳凤张大伟四川大学生命科学学院/生物资源与生态环境教育部重点实验室四川成都610065

土壤盐碱化是目前全球农业面临的主要环境挑战之一,为使植物在盐碱地上更好地生长,开展植物盐胁迫响应机制的研究具有重大意义。植物特有的同源结构域-亮氨酸拉链(HD-ZIP)家族转录因子HAT1在拟南芥中调控多种胁迫应答,到目前为止,HAT1... 详细信息

土壤盐碱化是目前全球农业面临的主要环境挑战之一,为使植物在盐碱地上更好地生长,开展植物盐胁迫响应机制的研究具有重大意义。植物特有的同源结构域-亮氨酸拉链(HD-ZIP)家族转录因子HAT1在拟南芥中调控多种胁迫应答,到目前为止,HAT1是否参与调控植物对盐胁迫的响应尚不清楚。文章围绕转录因子HAT1在拟南芥响应盐胁迫中的调控作用展开研究,证明了EIN3-HAT1-CSDs分子模块可以调控植物对盐胁迫的响应,以期拓展盐胁迫的分子调控网络。盐胁迫诱导EIN3的积累,EIN3抑制HAT1的表达,进而削弱HAT1对下游基因CSD1与CSD2的转录抑制,使抗氧化系统得以激活并清除过量的活性氧,从而增强植株的盐耐受能力。该信号通路为通过分子育种提高植物盐耐受性提供了一个新的潜在靶点。

关键词：盐胁迫 HAT1 CSD 转录调控

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直升机桨叶挥舞单摆吸振器吸振性能研究

直升机技术 2024年第2期 26-30,34页

作者：符烁方科喻国瑞周如传中国直升机设计研究所江西景德镇333001

设计了一种桨叶挥舞单摆吸振器,用来降低直升机旋翼系统的5阶垂向振动载荷。为了研究挥舞单摆吸振器的吸振性能,基于桨叶三维梁有限元模型,建立了旋翼与挥舞单摆吸振器的耦合动力学分析模型。以旋翼系统的固有频率和垂向载荷振幅为考核... 详细信息

设计了一种桨叶挥舞单摆吸振器,用来降低直升机旋翼系统的5阶垂向振动载荷。为了研究挥舞单摆吸振器的吸振性能,基于桨叶三维梁有限元模型,建立了旋翼与挥舞单摆吸振器的耦合动力学分析模型。以旋翼系统的固有频率和垂向载荷振幅为考核指标,开展旋翼-吸振器耦合动力学模型的动特性分析与吸振性能仿真分析,并研究了吸振器摆长与吸振频率的关系,以及不同吸振频率对吸振性能的影响。研究结果表明:旋翼加装挥舞单摆吸振器后,旋翼自身动特性变化很小,可以忽略吸振器对旋翼自身动特性的影响;通过合理选择吸振器吸振频率,旋翼5阶垂向振动载荷可以降低39%,减振效果良好;吸振器重量仅占目标旋翼系统重量的4%左右,具有显著的重量优势。

关键词：直升机旋翼系统振动载荷挥舞单摆吸振器吸振性能

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监测数据驱动的寒区混凝土坝温度特征分析

水电能源科学 2024年第6期42卷 166-170页

作者：陈锴陈伟楠段杭柯传芳牛瀚仪陈波国家能源局大坝安全监察中心浙江杭州311122 中国电建集团华东勘测设计研究院有限公司浙江杭州311122 浙江省水利水电勘测设计院有限责任公司浙江杭州310002 中国三峡建工(集团)有限公司四川成都610095 河海大学水利水电学院江苏南京210098 河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098

鉴于寒区混凝土坝的服役环境具有的冬季气温极低、温差悬殊、寒潮频发和冻融循环剧烈等特点对大坝安全带来的不利影响,针对寒区混凝土坝环境温度和坝体温度监测数据,通过构造反映温度增量距离和温度变幅距离的综合相似性距离指标,应用... 详细信息

鉴于寒区混凝土坝的服役环境具有的冬季气温极低、温差悬殊、寒潮频发和冻融循环剧烈等特点对大坝安全带来的不利影响,针对寒区混凝土坝环境温度和坝体温度监测数据,通过构造反映温度增量距离和温度变幅距离的综合相似性距离指标,应用层次凝聚聚类算法,提出了辨识寒区环境气温地域特征的数据聚类挖掘方法;并针对常规坝体温度场变化表征模型的不适用性,构建了融合谐波因子、气温前期项和水温前期项的寒区混凝土坝坝体温度场表征模型,提升了温度场刻画精度,为实现分析寒区混凝土坝温度场和演变规律,动态跟踪大坝安全状态提供了理论和技术支持。

关键词：严寒地区混凝土坝温度特征表征模型数据挖掘

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Simulation of Horizontal-Two-Dimension Focused Waves Using A Two-Layer Boussinesq-Type Model

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China Ocean Engineering 2023年第5期37卷 725-737页

作者： ZOU Wen-feng WANG Ping LIU Zhong-bo fang ke-zhao SUN Jia-wen ZHANG Ning-chuan key Laboratory of coastal and offshore engineering Dalian University of TechnologyDalian 116024China State Environmental Protection key Laboratory of Marine Ecosystem Restoration National Marine Environmental Monitoring CenterDalian 116023China Dalian Maritime University College of Transportation EngineeringDalian 116024China

Accurate simulation of the horizontal-two-dimension(H2D)focused wave group in deep water requires high accuracy of a numerical *** two-layer Boussinesq-type model(Liu and fang,2016;Liu et al.,2018)with the highest spatial derivative of 2 has high accuracy in both linear and nonlinear *** on the further development of the velocity equations(Liu et al.,2023),the H2D numerical model for water waves is established with the prediction-correction-iteration model in the finite difference method,and a composite fourth-order Adams-Bashforth-Moulton scheme is used for time *** wave generation method proposed by Hsiao et al.(2005)is applied and calibrated in this H2D *** numerical calculations lead to the following three main conclusions:First,compared with the analytical solution of Stokes linear waves,the calculated velocity profiles show higher accuracy by using the improved velocity ***,the simulations of the focused multidirectional wave group are carried out,and good agreements are found,demonstrating that the present H2D numerical model shows high accuracy in simulating focused multidirectional wave groups,and the effectiveness of the improved velocity formulas is also ***,the velocity profiles throughout the computational domain at the time of maximum wave crest are ***,the FFT method is used to obtain the amplitude with different frequencies for several locations,and the changes of the wavelet energy spectrum at different locations are presented for several cases.

关键词： focused wave horizontal-two-dimension model finite difference method nonlinear property

Distinct roles of two SEC scaffold proteins,AFF1 and AFF4,in regulating RNA polymerase II transcription elongation

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Journal of Molecular Cell Biology 2023年第8期15卷 15-27页

作者： Zhuanzhuan Che Xiaoxu Liu Qian Dai ke fang Chenghao Guo Junjie Yue Haitong fang Peng Xie Zhuojuan Luo Chengqi Lin The key Laboratory of Developmental Genes and Human Disease School of Life Science and TechnologySoutheast UniversityNanjing 210096China Co-innovation Center of Neuroregeneration Nantong UniversityNantong 226001China School of Biological Science and Medical Engineering Southeast UniversityNanjing 210096China Present address:School of Life Sciences Anhui Medical UniversityHefei 230032China

The super elongation complex(SEC)containing positive transcription elongation factor b plays a critical role in regulating transcription ***1 and AFF4,two members of the AF4/FMR2 family,act as central scaffold proteins of SEC and are associated with various human ***,their precise roles in transcriptional control remain ***,we investigate differences in the genomic distribution patterns of AFF1 and AFF4 around transcription start sites(TSSs).AFF1 mainly binds upstream of the TSS,while AFF4 is enriched downstream of the ***,disruption of AFF4 results in slow elongation and early termination in a subset of AFF4-bound active genes,whereas AFF1 deletion leads to fast elongation and transcriptional readthrough in the same subset of ***,AFF1 knockdown increases AFF4 levels at chromatin,and vice *** summary,these findings demonstrate that AFF1 and AFF4 function antagonistically to regulate RNA polymerase Ⅱ transcription.

关键词： super elongation complex AFF1 AFF4 transcription elongation early termination readthrough transcription

布拉氏酵母菌散联合清肠化瘀方治疗溃疡性结肠炎的效果及对炎性因子的影响

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中国肛肠病杂志 2024年第2期44卷 44-46页

作者：李晓玉方克云宋建青南阳市第三人民医院中医科河南南阳473000

目的:探讨布拉氏酵母菌散联合清肠化瘀方治疗溃疡性结肠炎(UC)的临床疗效及对炎性因子的影响。方法:选择2021年6月至2023年6月收治的96例UC患者为研究对象,随机分为观察组和对照组,各48例,对照组予美沙拉嗪+布拉氏酵母菌散治疗,观察组... 详细信息

目的:探讨布拉氏酵母菌散联合清肠化瘀方治疗溃疡性结肠炎(UC)的临床疗效及对炎性因子的影响。方法:选择2021年6月至2023年6月收治的96例UC患者为研究对象,随机分为观察组和对照组,各48例,对照组予美沙拉嗪+布拉氏酵母菌散治疗,观察组在对照组基础上予清肠化瘀方治疗。比较2组治疗总有效率、症状缓解情况及炎性因子水平。结果:观察组治疗总有效率(95.83%)高于对照组(81.25%),P<0.05。观察组治疗后腹泻、腹痛、里急后重感、脓血便评分低于对照组,P<0.05;观察组治疗后肿瘤坏死因子-ɑ(TNF-ɑ)、白介素-6(IL-6)、白介素-8(IL-8)水平均低于对照组,P<0.05。结论:UC治疗时联合应用布拉氏酵母菌散和清肠化瘀方可提高治疗效果,而且更有助于缓解临床症状、降低炎性因子水平。

关键词：溃疡性结肠炎布拉氏酵母菌散清肠化瘀方疗效炎性因子

Toward In Situ Atomistic Design of Catalytic Active Sites via Controlled Atmosphere Transmission Electron Microscopy

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Accounts of Materials Research 2023年第3期4卷 275-286页

作者： Wentao Yuan ke fang Ruiyang You Ze Zhang Yong Wang Center of Electron Microscopy and State key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

CONSPECTUS:Heterogeneous catalysts are widely used in a variety of industrial fields,including environmental protection,energy conversion,and chemical *** performance during reactions is usually determined by a small fraction of sites at the catalyst surfaces/interfaces,namely,the active ***,since the concept of the“active sites”was proposed by Hugh Taylor in the 1920s,determining the active site at the atomic level and understanding the molecular processes that happened at the active site have become the top priority in catalysis *** tried different methods to acquire various information related to the surface/interface active sites,pursuing their rational design at the atomic *** great achievements have been made in catalyst surface study,in situ atomistic design of active sites remains challenging,due to the lack of direct information and effective manipulation means concerning the active ***,many critical issues regarding the active sites under reaction conditions remain to be solved:(1)precisely identifying the active sites,which is the foundation for understanding the catalytical mechanism and rational design of the catalyst;(2)accurately manipulating the surface/interface active sites at the atomic scale,which is the basis for realizing the desired performance;(3)maintaining these designed active sites operating in a long-term with high efficiency without deactivation,which is extremely important to the practical applications of the *** these aspects rely on the fundamental understanding of the interactions between different surface/interface configurations of the catalyst and external environments(gas,pressure,temperature,etc.).In this Account,we present the recent progress in our group on the studies of surface/interface active sites via controlled atmosphere transmission electron microscopy(CATEM).We first briefly introduce the advances in CATEM technologies,including the window(c

关键词： catalyst rational determining

The Chinese national guidelines on diagnosis and management of cough （December 2010）

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Chinese Medical Journal 2011年第20期124卷 3207-3219页

作者： LAI ke-fang State key Laboratory of Respiratory Disease First Affiliated Hospital of Guangzhou Medical College Guangzhou Guangdong 510120 China

Cough is a defensive physiological reflex of the human body that enables vital clearance of secretionsand harmful elements from the respiratory tract; however, frequent and intense coughing may adversely impact on a patient＇s work, daily life and social activities. Cough is one of the most commonly observed symptoms in clinical practice arising from a wide range of aetiologies. A chronic cough may be overlooked by clinicians, particularly if reassured by the normal appearance on a chest radiograph. Furthermore, 70%-80% of these patients are readily mislabelled or diagnosed with ＂chronic bronchitis＂ or ＂bronchitis＂ in China, then typically treated with substantial but ineffective courses of antibiotics, or subjected to repeated investigations as a result of a diagnosis that is unclear, and may thus suffer more discomfort and financial burden from their disease.

关键词： cough diagnosis and management