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China Foundry 2024年第2期21卷 168-174页

作者： Zhi-yong Zhang Jiao-jiao Cheng Jia-qi Xie shi-bing Liu kun shi Jun Zhao Shenyang Research Institute of Foundry Co. Ltd.CAMShenyang 110022China National Key Laboratory of Advanced Casting Technologies Shenyang 110022China

Titanium matrix composites reinforced with ceramic particles are considered a promising engineering material due to their combination of high specific strength,low density,and high *** this study,the TA15-based composites reinforced with a volume fraction of 10% to 25%(TiB+TiC)were prepared using powder metallurgy and casting *** characterization and phase constitution were examined using optical microscopy(OM),scanning electron microscopy(SEM),and X-ray diffraction(XRD).In addition,the microhardness,room temperature(RT)and high temperature(HT)tensile properties of the composites were *** revealed that the reinforcements are distributed uniformly even in the composites with a high volume of TiB and ***,as the volume fraction exceeds 15%,TiB and TiC particles become coarsening and exhibit rod-like and dendritic-like *** increases gradually from 321.2 HV for the base alloy to a maximum of 473.3 HV as the reinforcement increases to 25vol.%.Tensile test results indicate that a reinforcement volume fraction above 20% is beneficial for enhancing tensile strength and yield strength at high temperatures,but it has an adverse effect on room temperature ***,if the reinforcement volume fraction is below 20%,it can improve high-temperature elongation when the temperature exceeds 600℃.

关键词： titanium matrix composites microstucture microhardness tensile properties in-situ synthesis

Drug delivery systems for colorectal cancer chemotherapy

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Chinese Chemical Letters 2024年第2期35卷 163-175页

作者： Wen Chen kun shi Yan Yu Peipei Yang Zhongwu Bei Dong Mo Liping Yuan Meng Pan Yu Chen Zhiyong Qian Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China

Colorectal cancer causes the third most common type of malignant tumors with high morbidity and *** is currently one of the most effective and common treatments for colorectal ***,the poor water solubility of some chemotherapeutics,untargeted drug delivery,and the undesirable systemic side effects of conventional treatment remain the major issues for colorectal cancer ***,drug delivery systems(DDS)based on biomaterials have been widely investigated and found to be capable of resolving those issues with good ***,the main goal of this review is to summarize and discuss the progress and potential advantages of different DDS for colorectal cancer *** not only reviewed the nanocarriers used to improve the solubility of chemotherapeutics,including liposomes,micelles,and nanoparticles,but also discussed targeted DDS based on specific ligand-receptor recognition and tumor microenvironmental stimulus ***,locally administered systems based on hydrogels and microspheres,which have been shown to increase drug accumulation at the tumor site while decreasing systemic toxicity,were also *** provides a good option for improving the efficacy of chemotherapy in the treatment of colorectal cancer.

关键词： Colorectal cancer Chemotherapy Drug delivery systems Solubility Targeted Local administration

Catalytic asymmetric dearomative azo-Diels–Alder reaction of 2-vinlyindoles

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Chinese Chemical Letters 2024年第4期35卷 357-362页

作者： Yu-Hang Miao Zheng-Xu Zhang Xu-Yi Huang Yuan-Zhao Hua shi-kun Jia Xiao Xiao Min-Can Wang Li-Ping Xu Guang-Jian Mei Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450052China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China Institute of Pharmaceutical Science and Technology Zhejiang University of TechnologyHangzhou 310014China

Due to the high electrophilic nature of azo-dienophiles, azo-Diels–Alder proceeds rapidly even without the need of a catalyst and is therefore regarded as the “click reaction”. This spontaneity causes strong background reaction and poses a daunting challenge to chemists for developing the catalytic asymmetric version. Reported herein is the first catalytic asymmetric dearomative azo-Diels–Alder reaction between2-vinylindoles and triazoledione. This protocol makes use of the high energy barrier of dearomatization to avert the strong background reaction of azo-Diels–Alder reaction, allowing the implementation of the projected reaction at ambient temperature. Density functional theory calculations have been performed to gain insights into the reaction mechanism and the origins of the enantioselectivity. By using this method,a variety of tetracyclic indole derivatives have been readily prepared in good to excellent yields and with excellent diastereo-and enantio–selectivities(33 examples, up to 97% yield and >99% ee, >20:1 dr).

关键词： Catalytic asymmetric dearomatization Azo-Diels–Alder reaction 2-Vinylindoles Chiral phosphoric acid Tetracyclic indole derivatives

An alfalfa MYB-like transcriptional factor MsMYBH positively regulates alfalfa seedling drought resistance and undergoes MsWAV3-mediated degradation

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Journal of Integrative Plant Biology 2024年第4期66卷 683-699页

作者： kun shi Jia Liu Huan Liang Hongbin Dong Jinli Zhang Yuanhong Wei Le Zhou Shaopeng Wang Jiahao Zhu Mingshu Cao Chris S.Jones Dongmei Ma Zan Wang College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Institute of Animal Sciences Chinese Academy of Agricultural SciencesBeijing 100193China AgResearch Grasslands Research Centre Palmerston North 4442New Zealand International Livestock Research Institute Nairobi 00100Kenya School of Ecology and Environment Ningxia UniversityYinchuan 750021China

Drought is a major threat to alfalfa(Medicago sativa L.)*** discovery of important alfalfa genes regulating drought response will facilitate breeding for drought-resistant alfalfa ***,we report a genome-wide association study of drought resistance in *** identified and functionally characterized an MYB-like transcription factor gene(MsMYBH),which increases the drought resistance in *** with the wild-types,the biomass and forage quality were enhanced in MsMYBH overexpressed *** RNA-seq,proteomics and chromatin immunoprecipitation analysis showed that MsMYBH can directly bind to the promoters of MsMCP1,MsMCP2,MsPRX1A and MsCARCAB to improve their *** outcomes of such interactions include better water balance,high photosynthetic efficiency and scavenge excess H_(2)O_(2)in response to ***,an E3 ubiquitin ligase(MsWAV3)was found to induce MsMYBH degradation under long-term drought,via the 26S proteasome ***,variable-number tandem repeats in MsMYBH promoter were characterized among a collection of germplasms,and the variation is associated with promoter ***,our findings shed light on the functions of MsMYBH and provide a pivotal gene that could be leveraged for breeding drought-resistant *** discovery also offers new insights into the mechanisms of drought resistance in alfalfa.

关键词： alfalfa drought resistance E3 ubiquitin ligase MsMYBH MsWAV3 MYB-like transcriptional factor

激光清洗时氟碳铝粉漆层表面粗糙度的分析及其对激光吸收的影响

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焊接学报 2024年第3期45卷 43-53,I0005页

作者：朱明张豪石坤侯宵飞石玗兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室兰州730050 兰州理工大学有色金属合金及加工教育部重点实验室兰州730050

激光清洗2024铝合金飞机蒙皮表面漆层过程中,粗糙表面的形成与演化会对漆层与激光的热交互作用及漆层去除机理产生较大的影响.1 064 nm脉冲激光逐层除漆过程中,分析了漆层表面形貌与粗糙程度的变化,研究了粗糙表面的产生机理及其演化规... 详细信息

激光清洗2024铝合金飞机蒙皮表面漆层过程中,粗糙表面的形成与演化会对漆层与激光的热交互作用及漆层去除机理产生较大的影响.1 064 nm脉冲激光逐层除漆过程中,分析了漆层表面形貌与粗糙程度的变化,研究了粗糙表面的产生机理及其演化规律,并通过建立漆层粗糙表面等效分析模型计算分析了漆层粗糙表面对激光吸收率的影响规律.结果表明,激光除漆过程中不同的去除机理作用后漆层均会出现粗糙表面,且粗糙表面的演化存在一定的规律;逐层除漆时,漆层粗糙表面对激光吸收率有明显增加作用,在激光作用7次后漆层粗糙表面对激光的吸收率增加了32.8%,如果采用固定的初始激光清洗工艺,会因吸收率增大导致铝合金基材产生损伤行为.

关键词：激光清洗铝合金漆层粗糙表面吸收率

Hsa-miR-483-5p/mRNA network that regulates chemotherapy resistance in locally advanced rectal cancer identified through plasma exosome transcriptomics

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World Journal of Clinical Oncology 2024年第8期15卷 1061-1077页

作者： Gan-Bin Li Wei-kun shi Xiao Zhang Xiao-Yuan Qiu Guo-Le Lin Department of General Surgery Peking Union Medical College HospitalPeking Union Medical CollegeBeijing 100730China

BACKGROUND Chemoresistance is the primary contributor to distant metastasis in the context of neoadjuvant chemoradiotherapy(nCRT)for rectal ***,the underlying mechanisms remain *** To detect the differential expression profiles of plasma exosomal microRNAs(miRNAs)in poor and good responders and explore the potential mechanisms of *** In this study,the profiles of plasma exosomal miRNAs were compared in two dimensions according to treatment responses(poor/good responders)and treatment courses(pre/post-nCRT)using RNA *** Exosome hsa-miR-483-5p was up-regulated in good responders *** analysis revealed that the target genes of hsa-miR-483-5p were mainly enriched in tumor-specific pathways,such as the MAPK signaling pathway,EGFR tyrosine kinase inhibitor resistance,Toll-like receptor signaling pathway,VEGF signaling pathway,and mTOR signaling *** analysis indicated that MAPK3,RAX2,and RNF165 were associated with inferior recurrence-free survival in patients with rectal cancer,and the profiles of MAPK3,TSPYL5,and ZNF-417 were correlated with tumor *** addition,the expression profiles of MAPK3,RNF165,and ZNF417 were negatively correlated with inhibitory concentration 50 ***,an hsa-miR-483-5p/MAPK3/RNF 165/ZNF417 network was *** This study provides insights into the mechanism of chemoresistance in terms of exosomal ***,further research is required within the framework of our established miRNA-mRNA network.

关键词： Locally advanced rectal cancer Neoadjuvant chemoradiotherapy Poor-responders Good responders Exosome miRNA

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提拉纺丝制备弹性离子液体凝胶纤维

高分子学报 2024年第5期55卷 573-581页

作者：时英坤王栋武培怡孙胜童纤维材料改性国家重点实验室东华大学化学与化工学院先进低维材料中心上海201620 武汉纺织大学材料科学与工程学院武汉430200

规模化制备兼具高弹性和高离子电导率的可拉伸导电纤维极具挑战性.为此,我们开发了一步法提拉纺丝策略,可连续制备高弹性离子液体凝胶纤维.其中,离子液体与聚合物基质以非共价相互作用结合,在纤维中稳定存在,并可大幅调控纤维力学性能.... 详细信息

规模化制备兼具高弹性和高离子电导率的可拉伸导电纤维极具挑战性.为此,我们开发了一步法提拉纺丝策略,可连续制备高弹性离子液体凝胶纤维.其中,离子液体与聚合物基质以非共价相互作用结合,在纤维中稳定存在,并可大幅调控纤维力学性能.得益于通过氢键自发纳米限域形成的多尺度相分离结构,所得离子液体凝胶纤维具有良好的拉伸性(707%)、高透明度(98%)、高回弹性(残余应变仅9%)、导电性(0.12 S·m^(-1))以及抗冻性能.此外,该纤维还可对湿气、温度以及应变表现出极为灵敏的信号感知能力.这一工作为开发面向智能感知的高性能离子导电纤维材料提供了设计思路.

关键词：纺丝导电纤维离子液体凝胶智能感知

基于BIM技术的工程项目施工进度计划编撰与优化

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工程建设与设计 2024年第10期 107-109页

作者：杨世昆贵州安顺交通旅游集团有限责任公司贵州安顺561099

针对施工进度管理效率低等问题,提出了利用BIM技术进行项目施工进度计划编撰及优化的方法,包括基础模型准备、计划编制和进度跟踪控制,并在关键路径法的基础上优化工序的逻辑关系。结果表明,其实现了项目缓冲区对工序安全时间的消除。基... 详细信息

针对施工进度管理效率低等问题,提出了利用BIM技术进行项目施工进度计划编撰及优化的方法,包括基础模型准备、计划编制和进度跟踪控制,并在关键路径法的基础上优化工序的逻辑关系。结果表明,其实现了项目缓冲区对工序安全时间的消除。基于BIM技术在工程项目施工进度管理中的作用,说明BIM技术能够对项目进度计划进行更加直接、高效的编排,可以有效减少项目的工期,实现了该技术在工程进度管理中的科学运用。

关键词： BIM技术工程项目施工进度计划编撰

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燃料电池膜电极失效原因及机理分析

能源与节能 2024年第3期 44-46,54页

作者：石锟上海捷氢科技股份有限公司上海201800

质子交换膜燃料电池的寿命与其核心部件质子交换膜的耐久性密切相关。为了探究影响膜电极耐久性的主要因素,采用扫描电子显微镜、 X射线荧光光谱仪、弹性模量测试等方法,对工况耐久循环后的失效膜电极进行了分析。结果表明,质子交换膜... 详细信息

质子交换膜燃料电池的寿命与其核心部件质子交换膜的耐久性密切相关。为了探究影响膜电极耐久性的主要因素,采用扫描电子显微镜、 X射线荧光光谱仪、弹性模量测试等方法,对工况耐久循环后的失效膜电极进行了分析。结果表明,质子交换膜树脂层脱落、增强层变形是导致膜电极窜漏失效的主要原因。进一步测试结果显示,膜电极中过渡金属元素局部富集,且其弹性模量在横向和纵向分别衰减了14%和25%。基于表征数据,深入研究了质子交换膜的失效机理,并提出了后续改进迭代方向。

关键词：燃料电池膜电极失效原因衰减机理

混合盐碱胁迫对紫花苜蓿幼苗生理和基因表达的影响

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草地学报 2024年第4期32卷 1044-1054页

作者：朱晨晨史昆何沁坤郑雨琴苑峰刘亚玲王赞中国农业大学草业科学与技术学院北京100193 内蒙古草业技术创新中心有限公司内蒙古呼和浩特010070

本研究以‘ZN-1’和‘保定’苜蓿(Medicago sativa L.‘Baoding’)为试验材料,以浓度梯度为0 mmol·L^(-1),40 mmol·L^(-1)和80 mmol·L^(-1),pH值为9.3的混合盐碱溶液(NaCl∶Na_(2)SO_(4)∶NaHCO_(3)∶Na_(2)CO_(3)摩尔比为1∶1∶1∶1)进行胁迫处理,比较2个紫花苜蓿幼苗的生长指标、生理指标和基因表达(ROS清除、离子转运和光合调控3类基因)差异,以期为解析紫花苜蓿耐混合盐碱胁迫响应机制提供理论依据。结果表明,随着混合盐碱胁迫浓度的增加,2个紫花苜蓿的株高、干重、叶绿素含量、光合速率以及Fv/Fm等均出现明显的损伤(P<0.05)。其中,‘ZN-1’的耐混合盐碱性显著高于‘保定’苜蓿,主要表现为‘ZN-1’的株高和生物量更高、叶绿素含量和抗氧化酶的活性更高,净光合速率更强,脯氨酸和可溶性糖含量更高,叶片ROS积累量和地下部Na+积累更少,ROS清除、脯氨酸生物合成、Na+液泡区隔化以及叶绿素维持相关编码基因的表达水平更高。因此,脯氨酸生物合成、Na+液泡区隔化、叶绿素维持以及抗氧化酶可能在‘ZN-1’耐混合盐碱胁迫中发挥重要作用。

关键词：紫花苜蓿混合盐碱胁迫生理响应基因表达

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