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Facile Synthesis of Aryl-Substituted Cycloarenes via Bismuth(III)Triflate-Catalyzed Cyclization of Vinyl Ethers

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CCS Chemistry 2021年第5期3卷 1445-1452页

作者： Wei Fan Yi Han shaoqiang dong Guangwu Li Xuefeng Lu Jishan Wu Department of Chemistry National University of SingaporeSingapore 117543 Department of Materials Science Fudan UniversityShanghai 200438 Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207

Cycloarenes are an essential class of polycyclic aromatic hydrocarbons with unique electronic structure,but their synthesis is very ***,we report a facile synthetic strategy primarily involving macrocyclization by the Suzuki coupling reaction,followed by bismuth(III)triflate-catalyzed cyclization of vinyl *** utilizing this approach,aryl-substituted soluble cycloarenes 7 and 8 with different sizes were obtained.X-ray crystallographic analysis revealed a slightly distorted backbone in the kekulene derivative 7 and a saddle-shaped skeleton in the octulene derivative *** length analysis suggested that both of the cycloarenes mainly complied with the Clar’s bonding model with dominant local aromaticity,which was also in accord with our NMR measurements and the theoretical calculations[nucleus-independent chemical shift[NICS],anisotropy of the induced current density(ACID),three-dimensional isochemical shielding surface(3D ICSS)].The optical properties were investigated by UV-Vis absorption and fluorescence spectral *** method opens opportunities to access various expanded and core-modified cycloarenes in the future.

关键词： polycyclic aromatic hydrocarbon cycloarene kekulene octulene aromaticity

Fusing Thienoisoindigo to the Conjugated Ribbons with Strong Absorption in the Second Near-Infrared Window

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CCS Chemistry 2022年第11期4卷 3497-3504页

作者： Yu Jiang Yaogang Zhang Yunfeng Deng shaoqiang dong Bo Li Yuanping Yi Zebing Zeng Hanjiao Chen Hao Luo Yanhou Geng Joint School of National University of Singapore Tianjin UniversityInternational Campus of Tianjin UniversityBinhai New CityFuzhou 350207 School of Materials Science and Engineering Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072 Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190 Institute ofMolecular Aggregation Science Tianjin UniversityTianjin 300072 State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082 Analytical&Testing Center Sichuan UniversityChengdu 610064 School of Optoelectronic Science and Engineering University of Electronic Science and Technology of China(UESTC)Chengdu 610054

Organic dyes with strong absorption in the second near-infrared(NIR-II)window(1000-1700 nm)have multiple ***,the design and synthesis of stable NIR-II absorbing organic dyes are very challenging and constantly defy our synthetic *** this work,we have successfully synthesized a series of soluble and stable fused thienoisoindigo(nThIID)*** absorption maximum(λ_(max))of the ribbons increases from 644 nm of 1ThIID to 1252 nm of ***,nThIIDs with n≥4 all display strong absorption in the NIR-II window with molar extinction coefficients(ε_(max))greater than 105 L mol^(−1)cm^(−1)atλ*** molecules are promising photothermal conversion dyes with photothermal conversion efficiencies of ca.60%under 1064 nm laser irradiation.

关键词： organic dyes second near-infrared window low bandgap thienoisoindigo conjugated molecules

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二辛基酞菁氧钒的合成、表征和半导体性质

科学通报 2016年第3期61卷 315-324页

作者：董少强田洪坤耿延候王佛松中国科学院长春应用化学研究所高分子物理与化学国家重点实验室长春130022

设计与合成了2,3-二辛基酞菁氧钒(2,3-C8OVPc),2,16(17)-二辛基酞菁氧钒(dp-C8OVPc),1,15-二辛基酞菁氧钒(1,15-C8OVPc)和1,18-二辛基酞菁氧钒(1,18-C8OVPc)4种可溶性酞菁氧钒衍生物,研究了辛基位置对该类化合物的物理化学性质、固态薄... 详细信息

设计与合成了2,3-二辛基酞菁氧钒(2,3-C8OVPc),2,16(17)-二辛基酞菁氧钒(dp-C8OVPc),1,15-二辛基酞菁氧钒(1,15-C8OVPc)和1,18-二辛基酞菁氧钒(1,18-C8OVPc)4种可溶性酞菁氧钒衍生物,研究了辛基位置对该类化合物的物理化学性质、固态薄膜形貌和有机薄膜晶体管(OTFT)器件性能的影响.在溶液状态下,辛基的位置对共轭分子的吸收光谱和前线轨道能级影响很小,它们的最大吸收峰均在700 nm左右,最高被占分子轨道(HOMO)和最低未占分子轨道(LUMO)能级分别约为-5.20和-3.80 eV.在薄膜状态下,吸收光谱显著红移,且红移幅度与辛基的位置有关.4个化合物在薄膜中均以edge-on的方式排列,由它们制备的底栅-顶接触型OTFT器件的迁移率均大于0.1 cm^2/(Vs),其中2,3-C8OVPc的迁移率最高,达到0.19 cm^2/(Vs).

关键词：有机半导体酞菁溶液加工有机薄膜晶体管迁移率

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国内外汽车产品认证对比分析

汽车实用技术 2018年第15期44卷 281-284页

作者：刘小利董少强陕西汽车集团有限公司陕西西安710200

文章陈述了国外产品认证管理模式与国内产品认证管理模式,把两者用来对比分析。以某企业为依托,从我国现行产品认证的申请信息化流程简介入手,阐述了各个认证模块存在的问题,最后提出解决这种问题的有效措施。以便于今后企业持续改进和... 详细信息

文章陈述了国外产品认证管理模式与国内产品认证管理模式,把两者用来对比分析。以某企业为依托,从我国现行产品认证的申请信息化流程简介入手,阐述了各个认证模块存在的问题,最后提出解决这种问题的有效措施。以便于今后企业持续改进和提高产品的一致性。

关键词：产品认证管理申报流程有效措施

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应用二阶灵敏度修改结构固有频率

华中理工大学学报 2000年第1期28卷 20-22页

作者：董绍强廖道训黄其柏华中理工大学机械科学与工程学院

提出了一种用二阶灵敏度修改结构固有频率 (特征值 )的算法 ,修改量是结构的设计参数 .引入二阶灵敏度主要是为了提高估计精度 ,通过非线性优化方法求解满足给定特征值要求的设计参数的变化量 .数值算例表明 ,所提出的算法在特征值修改... 详细信息

提出了一种用二阶灵敏度修改结构固有频率 (特征值 )的算法 ,修改量是结构的设计参数 .引入二阶灵敏度主要是为了提高估计精度 ,通过非线性优化方法求解满足给定特征值要求的设计参数的变化量 .数值算例表明 ,所提出的算法在特征值修改量达到 2 0 0

关键词：结构动力修改灵敏度固有频率非线性优化

Variations of Vegetation Phenology Extracted from Remote Sensing Data over the Tibetan Plateau Hinterland during 2000–2014

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Journal of Meteorological Research 2020年第4期34卷 786-797页

作者： Ya LIU Junbang WANG Jinwei dong shaoqiang WANG Hui YE Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural ResourcesChinese Academy of SciencesBeijing 100101 Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008

How vegetation phenology responds to climate change is a key to the understanding of the mechanisms driving historic and future changes in regional terrestrial ecosystem productivity. Based on the 250-m and 8-day moderate resolution imaging spectroradiometer(MODIS) normalized difference vegetation index(NDVI) data for 2000-2014 in the Three-River Source Region(TRSR) of Qinghai Province, China, i.e., the hinterland of the Tibetan Plateau, we extracted relevant vegetation phenological information(e.g., start, end, and length of growing season) and analyzed the changes in the TRSR vegetation in response to climate change. The results reveal that, under the increasingly warm and humid climate, the start of vegetation growing season(SOS) advanced 1.03 day yr-1 while the end of vegetation growing season(EOS) exhibited no significant changes, which led to extended growing season length. It is found that the SOS was greatly affected by the preceding winter precipitation, with progressively enhanced precipitation facilitating an earlier SOS. Moreover, as the variations of SOS and its trend depended strongly on topography, we estimated the elevation break-points for SOS. The lower the elevations were, the earlier the SOS started. In the areas below 3095-m elevation, the SOS delay changed rapidly with increasing elevation;whereas above that, the SOS changes were relatively minor. The SOS trend had three elevation break-points at 2660, 3880, and 5240 m.

关键词： Three-River Source Region(TRSR) start of vegetation growing season(SOS) spatiotemporal change elevation climate change China

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中药黄芪的药理作用分析及临床应用效果

中国卫生标准管理 2024年第11期15卷 126-130页

作者：董立丛绍强程明丽王丹史家文泰安市中心医院/青岛大学附属泰安市中心医院/泰山医养中心药物临床试验机构办公室山东泰安271000

目的分析中药黄芪的药理作用及其临床应用效果。方法选取2022年10月—2023年10月青岛大学附属泰安市中心医院采用黄芪治疗的88例患者作为观察组,另选择同期应用西医治疗的88例作为对照组,观察运用中药黄芪后患者的临床疗效。结果观察组(... 详细信息

目的分析中药黄芪的药理作用及其临床应用效果。方法选取2022年10月—2023年10月青岛大学附属泰安市中心医院采用黄芪治疗的88例患者作为观察组,另选择同期应用西医治疗的88例作为对照组,观察运用中药黄芪后患者的临床疗效。结果观察组(95.45%)急性心肌梗死合并心力衰竭总有效率高于对照组(72.73%)(P<0.05)。观察组(90.91%)扩张型心肌病伴心力衰竭总有效率高于对照组(68.18%)(P<0.05)。观察组糖尿病周围神经病变总有效率(100%)高于对照组(77.27%)(P<0.05)。观察组脑血栓总有效率(95.45%)高于对照组(68.18%)(P<0.05)。结论中药黄芪在治疗糖尿病周围神经病变、急性心肌梗死伴心衰、脑血栓后遗症以及扩张型心肌病合并心力衰竭患者中疗效较理想,为临床治疗提供有力依据,同时也为中药在心血管和神经系统疾病治疗中的应用提供新思路。但仍需要进一步的研究来验证其机制和安全性。

关键词：中药黄芪药理作用糖尿病周围神经病变急性心肌梗死心力衰竭脑血栓扩张型心肌病

Spatiotemporal pattern of the dynamics in area,production,and yield of Aus rice in Bangladesh and its response to droughts from 1980 to 2018

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Journal of Geographical Sciences 2022年第10期32卷 2069-2084页

作者： KHONDAKAR Arifuzzaman dong Jinwei LI Zhichao DENG Xiangzheng SINGHA Mrinal RAHMAN Md.Mizanur JIN Zhenong WANG shaoqiang ZHEN Lin XIAO Xiangming Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100094China Department of Geography and Environment Pabna University of Science and TechnologyPabna 6600Bangladesh Deputy Director(Monitoring) Field Services WingDepartment of Agricultural ExtensionMinistry of AgricultureBangladesh Department of Bioproducts and Biosystems Engineering University of Minnesota-Twin CitiesSaint PaulMNUSA Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China Department of Microbiology and Plant Biology University of OklahomaNorman OK 73019USA

Bangladesh is one of the most vulnerable countries to natural disasters such as droughts in the *** pre-monsoon Aus rice in Bangladesh depends on rainfall and is threatened by increasing ***,limited information on the changes in Aus rice as well as droughts hamper our understanding of the country’s agricultural resilience and adaption to ***,we collected all the official statistical data of Aus rice at the district level from 1980 to 2018,and examined the interannual variations of area,yield,and *** results showed both area and production of Aus rice decreased significantly(61.58×103 ha yr-1 and 17.21×103 *** yr-1,respectively),while yield increased significantly(0.03 *** ha-1 yr-1).We also found a significantly increasing trend of droughts in 88%of area based on the Palmer Drought Severity Index(PDSI)data,especially in those rainfed agricultural ***,we found significant positive correlations between PDSI and Aus rice area(production)in 33(25)out of 64 *** is hardly a relationship between PDSI and yield,likely due to the improved management and increasing irrigated *** continuous drought monitoring,combined irrigation(surface and groundwater)systems,and conservation and precision agriculture are highly recommended in these drought-prone districts to ensure food security in Bangladesh.

关键词： Aus rice droughts acreage production yield PDSI Bangladesh

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基于稳态传热分析的高炉炉壁温度场建模方法

化工学报 2023年第12期74卷 4863-4880页

作者：徐思远潘冬蒋朝辉刘少强余浩洋中南大学自动化学院湖南长沙410083

高炉炉壁温度场是掌握炉内热负荷状态和燃料燃烧情况、及时发现高炉异常工况、保障高炉稳定顺行的重要信息。针对现有炉壁温度场获取难及温度场建模过程中未考虑渣皮脱落与生成现象等问题,提出一种基于稳态传热分析的高炉炉壁温度场建... 详细信息

高炉炉壁温度场是掌握炉内热负荷状态和燃料燃烧情况、及时发现高炉异常工况、保障高炉稳定顺行的重要信息。针对现有炉壁温度场获取难及温度场建模过程中未考虑渣皮脱落与生成现象等问题,提出一种基于稳态传热分析的高炉炉壁温度场建模方法。首先,利用COMSOL仿真软件搭建炉壁三维仿真模型;其次,充分考虑渣皮对炉壁温度变化的影响,建立包含渣皮热源项的稳态传热模型,获得初始炉壁内表面温度场;然后,为提高温度场模型精度,基于热传导反问题理论,以冷却壁中热电偶的实测温度为参考,构建炉壁温度场修正模型,实现炉壁温度场数据的迭代修正。实验表明经温度场修正模型修正后,传热模型的计算误差控制在5%以内,满足现场检测精度要求,并能可视化展示炉壁温度场,为高炉调控操作提供了可靠的炉壁温度场数据。

关键词：高炉炉壁渣皮温度场建模温度迭代修正热力学传热热传导反问题热传导