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One-Pot Synthesis of Axially and Centrally Chiral A-type Nanogrids

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Chinese Journal of Chemistry 2023年第22期41卷 2969-2974页

作者： ying wei Xue Du Wan-Xin Huang Ming-Yang Fu Zheng Zhang Chun-Xiao Zhong Yi-Ru Wang HaiFeng Ling Ling-Hai Xie wei Huang Centrefor Molecular Systems and Organic Devices(CMSOD@IAM) State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM)Nanjing University of Posts&Telecommunications9 Wenyuan RoadNanjingJiangsu 210023China Frontiers Science Centerfor Flexible Electronics(FSCFE) MIT Key Laboratory of Flexible Electronics(KLoFE)Northwestern Poly-technical UniversityXi'anShaanxi710072China

A novel type of A-type nanogrids(AGs)with axial and central chirality was synthesized via Friedel-Crafts gridization of thiophenes and difluorenyl biaromatic derivatives,yielding 9%-30%.Additionally,the effect of stereoisomers of 1,1'-binaphthyl difluorenols(BINDFOH)was investigated to demonstrate that R/S-BINDFOH is more advantageous for the synthesis of AGs than Mix-BINDFOH.Furthermore,tests on OFET memory devices showed that AGs have a larger storage window,indicating potential for data storage applications.

关键词： Friedel-Crafts gridization A-type nanogrids OFET Chirality Nanostructures Organic chemistry

Ce-promoted Mn/ZSM-5 catalysts for highly efficient decomposition of ozone

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Journal of Environmental Sciences 2021年第5期33卷 219-228页

作者： Linlin wei Hongxia Chen ying wei Jingbo Jia Runduo Zhang State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Energy Environmental CatalysisBeijing University of Chemical TechnologyBeijing 100029PR China

Manganese oxides supported by ZSM-5 zeolite(Mn/ZSM-5) as well as their further modified by Ce promoter were achieved by simple impregnation method for ozone catalytic decomposition. The yCe20Mn/ZSM-5–81 catalyst with 8% Ce loading showed the highest catalytic activity at relative humidity of 50% and a space velocity of 360 L/(g × hr), giving 93% conversion of 600 ppm O_(3) after 5 hr. Moreover, this sample still maintained highly activity and stability in humid air with 50%–70% relative humidity. Series of physicochemical characterization including X-ray diffraction, temperature-programmed technology(NH_3-TPD and H_(2)-TPR), X-ray photoelectron spectroscopy and oxygen isotopic exchange were introduced to disclose the structure-performance relationship. The results indicated that moderate Si/Al ratio(81) of zeolite support was beneficial for ozone decomposition owing to the synergies of acidity and hydrophobicity. Furthermore, compared with 20 Mn/ZSM-5-81, Ce doping could enhance the amount of low valance manganese(such as Mn^(2+) and Mn^(3+)). Besides, the Ce^(3+)/Ce^(4+) ratio of 8Ce20Mn/ZSM-5-81 sample was higher than that of 4Ce_(2)0 Mn/ZSM-5-81. Additionally, the synergy between the MnO_x and CeO_(2) could easily transfer electron via the redox cycle, thus resulting in an increased reducibility at low temperatures and high concentration of surface oxygen. This study provides important insights to the utilization of porous zeolite with high surface area to disperse active component of manganese for ozone decomposition.

关键词： Manganese oxide ZSM-5 zeolite Ce promoter Adsorbed oxygen Ozone decomposition

A nano-delivery system expands the insecticidal target of thiamethoxam to include a devastating pest,the fall armyworm

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Insect Science 2023年第3期30卷 803-815页

作者： Qin-Hong Jiang Ting Li Yan Liu Zi-Yi Zhou Yang Yang ying wei Mei-Zhen Yin Jie Shen Shuo Yan Department of Plant Biosecurity and MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests College of Plant ProtectionChina Agricultural UniversityBejingChina State Key Laboratory of Chemical Resource Engineering Bejing Lab of Biomedical MaterialsBejing University of Chemical TechnologyBeijingChina

Nano-delivery systems have been applied to deliver various synthetic/botanical pesticides to increase the efficiency of pesticide use and reduce the volumes of pesticides applied.Previous studies have supported the hypothesis that the nanocarriers can help expand the insecticidal target of pesticides to include non-target pests.However,the potential mechanism underlying this interesting phenomenon remains unclear.Herein,a widely applied star polycation(SPc)nanocarrier was synthesized to construct a thiamethoxam(TMX)nano-delivery system.The SPc-based delivery system could promote the translocation of exogenous substances across the membrane of Sf9 cells,increase the cytotoxicity of TMX against Sf9 cells by nearly 20%,and expand the insecticidal target of TMX to include Spodoptera frugiperda(the fall armyworm),with a 27.5%mortality increase at a concentration of 0.25 mg/mL.Moreover,the RNA-seq analysis demonstrated that the SPc could upregulate various transport-related genes,such as Rab,SORT1,CYTH,and PIKfive,for the enhanced cellular uptake of TMX.Furthermore,enhanced cell death in larvae treated with the TMX-SPc complex was observed through changes in the expression levels of death-related genes,such as Casp7,BIRC5,MSK1,and PGAM5.The SPc-based nano-delivery system improved the cellular uptake of TMX and expanded its insecticidal target by adjusting the expression levels of death-related genes.The current study mainly identified the transport and cell death genes related to nanocarrier-based insecticidal target expansion,which is beneficial for understanding the bioactivity enhancement of the nano-delivery system.

关键词： insecticides nanotechnology nanomaterials thiamethoxam

传染病扩散的对策及医疗资源配置问题研究——以新冠疫情为例

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工业工程与管理 2024年第2期29卷 114-129页

作者：李锋魏莹华南理工大学工商管理学院广东广州510640 暨南大学企业管理系广东广州510632

疫情防控下的医疗资源配置需要同时考虑资源的服务水平和利用率两大评价指标。首先,将人员流动因素等引入流行病扩散的易感-潜伏-传染-恢复模型中,构建更加符合流行病扩散的多智能体模型。通过仿真,不仅能够得到传染病感染的总人数,还... 详细信息

疫情防控下的医疗资源配置需要同时考虑资源的服务水平和利用率两大评价指标。首先,将人员流动因素等引入流行病扩散的易感-潜伏-传染-恢复模型中,构建更加符合流行病扩散的多智能体模型。通过仿真,不仅能够得到传染病感染的总人数,还能得到病患人数的实时变化情况。结合病患人数的动态变化,计算医疗资源的需求满足率和利用率指标。在此基础上,分析了包括佩戴口罩、隔离病患、接种疫苗、筛查核酸和“封城”等多种疫情防控措施的实施效果,以及这些防控措施对医疗资源的影响。最后,以病床为例进行了医疗资源配置问题分析。结果表明:及时启动防疫对策,能够大幅降低对医疗资源的数量需求;反之,防疫对策不能够减少对医疗资源的数量需求,仅能够降低病患总人数。

关键词：传染病扩散资源配置对策研究 SEIR模型元胞自动机

我国主要河流水系硝态氮污染特征及定量源解析

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环境科学 2024年第2期45卷 755-767页

作者：韦英怀胡敏鹏陈丁江浙江大学环境与资源学院杭州310058 浙江大学环境修复与生态健康教育部重点实验室杭州310058 浙江大学浙江省农业资源与环境重点实验室杭州310058

准确定量污染来源组成是有效控制水体硝态氮污染的关键科学基础.采用荟萃分析的方法,收集了2000~2022年我国167条主要水系河流的硝态氮浓度和硝态氮的氮氧同位素等数据,分析了七大主要河流水系硝态氮污染的时空变异规律及其转化特征,定... 详细信息

准确定量污染来源组成是有效控制水体硝态氮污染的关键科学基础.采用荟萃分析的方法,收集了2000~2022年我国167条主要水系河流的硝态氮浓度和硝态氮的氮氧同位素等数据,分析了七大主要河流水系硝态氮污染的时空变异规律及其转化特征,定量识别了河流硝态氮的污染来源组成.结果表明,我国主要河流水系ρ(NO_(3)^(-)-N)平均值为(4.54±3.99)mg·L_(-1),其中9.6%的河流硝态氮浓度超过我国地表水环境质量标准(GB 3838-2002)规定的限值(10.0 mg·L_(-1)),海河水系的硝态氮污染最为严重.东部地区河流水系的硝态氮浓度总体高于西部,各大河流水系支流的硝态氮浓度高于干流.除黄河水系以外,其他水系枯水期的硝态氮浓度总体高于丰水期.珠江水系、黄河水系中下游地区、辽河水系中游地区、松花江水系,以及海河水系河流水体存在显著的硝化作用,而长江水系、淮河水系和珠江水系下游地区存在显著的反硝化作用.污水/粪肥是长江水系、海河水系、辽河水系,以及东南诸河水系硝态氮的主要来源(>50%),土壤氮是松花江水系硝态氮的主要来源(56.4%),化肥氮、土壤氮和污水/粪肥对珠江水系、淮河水系和黄河水系硝态氮的污染贡献为20%~40%.污水/粪肥对水系支流硝态氮贡献率总体大于干流的,土壤氮对干流硝态氮的贡献总体大于支流的.土壤氮、化肥氮和大气沉降氮对丰水期河流硝态氮的贡献率高于枯水期,而污水/粪肥对枯水期河流硝态氮的污染贡献率高于丰水期.因此,海河水系、长江水系、辽河水系、黄河水系支流与下游干流地区和珠江水系下游地区应重点控制生活和生产的污水排放等点源污染,而淮河水系、松花江水系、黄河水系中游干流地区和珠江水系中上游地区要重点控制化肥和土壤氮等流失造成的非点源污染.研究结果可为有效控制我国各河流水系硝态氮的污染提供科学依据.

关键词：硝态氮源解析河流氮氧同位素非点源污染点源污染

基于CNN-LSTM的燃气轮机燃烧室故障预警

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热能动力工程 2024年第1期39卷 191-197,215页

作者：周锐康英伟上海电力大学自动化工程学院上海200090

为了解决燃气轮机燃烧室中的故障问题,结合深度学习的优势,在长短期记忆网络(Long Short-term Memory,LSTM)的基础上,提出了一种基于卷积神经网络-长短期记忆网络的燃烧室故障预警方法。首先,根据正常的历史运行数据构建燃烧室的预警模... 详细信息

为了解决燃气轮机燃烧室中的故障问题,结合深度学习的优势,在长短期记忆网络(Long Short-term Memory,LSTM)的基础上,提出了一种基于卷积神经网络-长短期记忆网络的燃烧室故障预警方法。首先,根据正常的历史运行数据构建燃烧室的预警模型,再将特征参数输入到预警模型中得到预测值,预测值与实际值之间的偏离度可以反映燃烧室内部工作是否正常。考虑到模型预测结果的非平稳性和非线性等特点,引入滑动窗口法确定故障预警阈值,最后根据确定的预警阈值判断是否出现故障。采用某燃气-蒸汽联合循环发电机组仿真平台对上述模型进行验证。仿真结果表明:该模型相较于LSTM预测模型具有更高的精确度,可以及时发现故障征兆,并对燃烧室故障做出有效预警。

关键词：燃烧室故障预警 LSTM神经网络卷积神经网络预测偏离度滑动窗口法

Dipeptides VL increase protein accumulation in C2C12 cells by activating the Akt-mTOR pathway and inhibiting the NF-κB pathway

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Food Bioscience 2022年第1期45卷 122-130页

作者： Mingliang Li ying wei Zhiyuan Feng Muyi Cai Yaguang Xu Ruizeng Gu Yongqing Ma Xingchang Pan Beijing Engineering Research Center of Protein&Functional Peptides China National Research Institute of Food and Fermentation IndustriesBeijing 100015PR China

The Akt-mTOR signaling pathway plays a central role in regulating intracellular protein metabolism,and the NF-κB signaling pathway plays a vital role in developing skeletal muscle atrophy.In this study,we took the three dipeptides Val-Leu(VL),Leu-Leu(LL),and Leu-Gln(LQ)identified from corn peptides as the research objects and proved that peptides could promote C2C12 cell differentiation and protein synthesis by activating the Akt-mTOR signaling pathway.On the other hand,the dipeptides also inhibited the classical pathway of the NF-κB signaling pathway,down-regulated the expression of two E3 ubiquitin ligases MAFbx and MURF-1,attenuated apoptosis induced by TNF-α,and thus inhibited protein degradation in cells.In conclusion,the dipeptides isolated from corn peptides showed the effect of increasing protein accumulation in skeletal muscle,suggesting the application potential of corn peptides in promoting the growth of skeletal muscle mass.In addition,this experiment compared the different characteristics of the effects of the dipeptide VL and its corresponding amino acid mixture on the Akt-mTOR signaling pathway.

关键词： VL C2C12 Akt-mTOR NF-κB Skeletal muscle

国家目标下的创新生态系统构建:以极紫外光刻机为例

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学术研究 2024年第1期 89-97页

作者：李君然魏莹清华大学人文学院写作与沟通教学中心北京100086 中国科学院科技战略咨询研究院北京100190

产业权力是一国在战略性产业国际体系中影响其他国家行为和利益以维护本国利益或相对优势的能力。新型举国体制面向国家重大战略需求突破关键核心技术的最终指向也在于谋求产业权力。产业权力的形成是国家与市场互相嵌入的过程,也是一... 详细信息

产业权力是一国在战略性产业国际体系中影响其他国家行为和利益以维护本国利益或相对优势的能力。新型举国体制面向国家重大战略需求突破关键核心技术的最终指向也在于谋求产业权力。产业权力的形成是国家与市场互相嵌入的过程,也是一个系统性的过程。本文分析了创新生态系统中的权力结构及其形成过程,并以极紫外光刻机为例说明美国如何利用开放的市场机制完成其产业权力构建。研究发现,美国通过设计愿景、投放资源、定义规则等方式,成功在极紫外光刻机创新生态系统中嵌入了产业权力,实现其对极紫外光刻机产业的控制。创新生态系统能够调和国家战略控制与市场追求行业利润的目标差异,这为新型举国体制在国家战略目标下动员和整合各类要素资源、发挥政府机制与市场机制的作用提供了参考。

关键词：创新生态系统产业权力新型举国体制极紫外光刻机

阳关:西汉经敦煌郡与西域间交流交往的关隘——基于史籍与出土文献的考察

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苏州大学学报（哲学社会科学版） 2024年第1期45卷 176-182页

作者：魏迎春郑炳林兰州大学敦煌学研究所甘肃兰州730020

西汉敦煌郡阳关、玉门关的命名与设置布局应是仿照中原关隘布局而来的,即复制或者移植了中原地区的关隘名称与布局。而悬泉汉简所载“敦煌塞”很可能就是指阳关一带的边塞,也即阳关都尉所辖边塞。阳关是西汉中原前往西域地区使用最多的... 详细信息

西汉敦煌郡阳关、玉门关的命名与设置布局应是仿照中原关隘布局而来的,即复制或者移植了中原地区的关隘名称与布局。而悬泉汉简所载“敦煌塞”很可能就是指阳关一带的边塞,也即阳关都尉所辖边塞。阳关是西汉中原前往西域地区使用最多的关隘。西汉敦煌郡九置组成的邮驿系统向东可通达长安,向西从最西端的龙勒置就近经由阳关出塞,又经文候鄣可抵达鄯善国伊循城,至此连接西域南道。这条阳关通道相对玉门关通道更便于通行,因而,阳关通道是文书传送之路,也是戍卒、施刑士来往之路,还是西汉与西域间通使、通商之路。因此,阳关应当是为了与西域诸国通使通商需要而设置的关隘,此后成为西汉中原与西域交流交往交融的一扇大门。

关键词：西汉阳关敦煌郡西域