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以邻苯二甲酸结构与四苯基乙烯核心构筑点亮型Pb^(2+)与Al^(3+)荧光传感器

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科学通报 2022年第20期67卷 2405-2412页

作者：刘静董永强北京师范大学化学学院能量转换与存储材料北京市重点实验室北京100875

铅和铝在生产生活中的广泛使用会造成环境及水体污染而危害人类健康,对环境及生物体中Pb^(2+)和Al^(3+)的实时监测有重要的意义.荧光探针可对金属离子实现高灵敏度、实时快速检测.传统的荧光分子易发生聚集淬灭而影响荧光探针的性质,而... 详细信息

铅和铝在生产生活中的广泛使用会造成环境及水体污染而危害人类健康,对环境及生物体中Pb^(2+)和Al^(3+)的实时监测有重要的意义.荧光探针可对金属离子实现高灵敏度、实时快速检测.传统的荧光分子易发生聚集淬灭而影响荧光探针的性质,而以具有聚集诱导发光性质的荧光分子为核心,可设计合成高灵敏度的点亮型荧光探针.本文以邻苯二甲酸结构为电子受体,以四苯基乙烯(tetraphenylethylene,TPE)为核心,构筑了两个具有不同电子给体结构的水溶性点亮型Pb^(2+)和Al^(3+)荧光探针,具有强电子给体的探针与被检测物作用后发出更长波长的荧光.研究了两种荧光探针的检测灵敏度和抗干扰性,探究了其检测机理,两个荧光探针对Al的检出限均低于世界卫生组织(WHO)饮用水中Al含量标准.

关键词：聚集诱导发光(AIE) Pb^(2+) Al^(3+) 荧光探针邻苯二甲酸

Magnetron sputtered nickel oxide with suppressed interfacial defect states for efficient inverted perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 348-355页

作者： Guoqiang Ma Qin Tan Zhaoning Li Jingwei Xiu Jiafeng Wang Tianle Cheng dong He qiang Sun Xuhang Ma Francesco Lamberti Zhubing He Department of Materials Science and Engineering Institute of Innovative Materials (I2M) Shenzhen Key Laboratory of Full Spectral Solar Electricity Generation (FSSEG)Southern University of Science and Technology (SUSTech) Core Research Facilities Southern University of Science and Technology Department of Chemical Sciences Department of Industrial Engineering University of Padova

Widely used spin-coated nickle oxide （NiOx） based perovskite solar cells often suffer from severe interfacial reactions between the NiOxand adjacent perovskite layers due to surface defect states,which inherently impair device performance in a long-term view,even with surface molecule *** this study,we developed high-quality magnetron-sputtered NiOxthin films through detailed process optimization,and compared systematically sputtered and spin-coated NiOxthin film surfaces from materials to *** sputtered NiOxfilms exhibit improved crystallinity,smoother surfaces,and significantly reduced Ni3+or Ni vacancies compared to their spin-coated ***,the interface between the perovskite and sputtered NiOxfilm shows a substantially reduced density of defect *** solar cells （PSCs） fabricated with our optimally sputtered NiOxfilms achieved a high power conversion efficiency （PCE） of up to 19.93%and demonstrated enhanced stability,maintaining 86.2% efficiency during 500 h of maximum power point tracking under one standard sun ***,with the surface modification using (4-(2,7-dibromo-9,9-dimethylacridin-10（9H）-yl)butyl)p hosphonic acid （DMAcPA）,the device PCE was further promoted to 23.07%,which is the highest value reported for sputtered NiOxbased PSCs so far.

关键词： Perovskite

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高温下制焦温度对煤焦气化活性的影响

燃料化学学报 2002年第1期30卷 16-20页

作者：唐黎华吴勇强朱学栋朱子彬华东理工大学化工工艺研究所上海200237

研究了高温下扎莱诺尔、后布连、东胜、西山和沈阳五种煤焦的碳转化率和气化速率与制焦温度的关系 ,并考察了气化温度对不同制焦温度下所制得扎莱诺尔煤焦气化活性的影响。实验表明 :制焦温度对煤的气化活性的影响不尽相同 ,在较低的制... 详细信息

研究了高温下扎莱诺尔、后布连、东胜、西山和沈阳五种煤焦的碳转化率和气化速率与制焦温度的关系 ,并考察了气化温度对不同制焦温度下所制得扎莱诺尔煤焦气化活性的影响。实验表明 :制焦温度对煤的气化活性的影响不尽相同 ,在较低的制焦温度 10 0 0℃下 ,五种煤焦表现出很大的气化速率和碳转化率的差距 ,但随制焦温度的提高煤焦的气化活性下降 ,制焦温度在 12 0 0℃时 ,四种煤焦的气化速率逐步接近 ,当制焦温度达到 140 0℃时 ,除沈阳煤外 ,四种煤焦的气化反应速率与碳转化率分别趋于相同。从五种煤以及不同制焦温度下所制得相应焦的SEM分析发现 ,当制焦温度超过相应煤灰分的软化温度时 ,制焦温度将直接影响焦中矿物质的分散程度及聚集状态。随着温度的提高 ,矿物质颗粒也开始从初始的随机分散分布发展到团聚 ,温度越高 ,聚集态的矿物质颗粒尺寸越大 ,其催化作用也越弱。在高温下灰份的熔融是制焦温度影响煤焦气化速率的最重要原因之一。

关键词：制焦温度气化活性灰熔点煤焦煤气化

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期 174-180页

作者： Fan-Xiao Meng Xing-Yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du yong-qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

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Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-qiang Jiao Ming Li Xi Chen Mei-Ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei Li Xue-Yuan Liu yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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Synthesis and Crystal Structure of N,N′-4-aminomethyl-pyromellitic diimide

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1176-1180页

作者： LU Xing-qiang PI Xiang-dong SU Cheng-yong School of Chemistry and Chemical Engineering Sun Yat-Sen University Guangzhou 510275 China Chemtcal Envtronmental Protectton Monitoring Station of Hubei Wuhan 430060 China

The title compound N,N′-4-aminomethyl-pyromellitic diimide （4-pmpmd） crystallizes in monoclinic, space group P21/c with a = 4.785（1）, b = 6.200（1）, c = 29.907（2） A, β = 93.583（11）°, V= 885.5（2） A^3, Dc = 1.494 g/cm^3, Z= 2, C22H14N4O4, Mr = 398.37,/t（MoKα） = 0.106 mm^-1 and F（000） = 412, and its structure was refined to R = 0.0469 and wR = 0.1017 for 1194 observed reflections （F0 〉 4σ（F0））. The X-ray diffraction shows the existence of the staggered strong intermolecular C-H…O （DA） hydrogen bonds between adjacent molecules, the intermo- lecular C-H…π hydrogen bonds and the weak π…π stacking interactions, leading to the formation of multi-dimensional supramolecular network based on the Z-mode conformation of the title compound.

关键词： N,N′-4-aminomethyl-pyromellitic diimide intermolecular weak interactions,supramolecular network

Impacts of climate change on the potential forest productivity based on a climate-driven biophysical model in northeastern China

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Journal of Forestry Research 2020年第6期31卷 2273-2286页

作者： Wen-qiang Gao Xiang-dong Lei Li-yong Fu Institute of Forest Resource Information Techniques Chinese Academy of ForestryKey Laboratory of Forest Management and Growth ModellingState Forestry and Grassland AdministrationBeijing 100091People’s Republic of China

Climate warming is expected to influence forest growth,composition and ***,accurately estimating and predicting forest biomass,potential productivity or forest growth is still a challenge for forest managers dealing with land-use at the stand to regional *** the present study,we predicted the potential productivity(PP)of forest under current and future climate scenarios(RCP2.6,RCP4.5,RCP6.0 and RCP8.5)in Jilin province,northeastern China by using Paterson’s Climate Vegetation and Productivity(CVP)index *** PP was validated by comparing it with the mean and maximum net primary production calculated from light energy utilization(GLM_PEM).Our results indicated that using the CVP index model is partially valid for predicting the potential forest productivity in northeastern *** exhibited obvious spatial heterogeneity varying from 4.6 to 8.9 m3 ha-1 year-1 with an increasing tendency from northwest to southeast driven by the precipitation across the *** number of vegetation-active months,precipitation and insolation coefficient were identified as the primary factors affecting PP,but no significant relationship was found for warmest temperature or temperature *** future climate scenarios,PP across the Jilin Province is expected to increase from 1.38%(RCP2.6 in 2050)to 15.30%(RCP8.5 in 2070),especially in the eastern Songnen Plain(SE)for the RCP8.5 scenarios.

关键词： Climate vegetation and productivity index Potential productivity Climate change

PAM-PAA microgel inverse opal photonic crystal and pH response

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Chinese Chemical Letters 2007年第11期18卷 1395-1398页

作者： yong qiang He Xiao dong Wang Jian Ying Wang Yan Feng yong qiang Zhao Xiu dong You School of Science Tianjin University Tianjin 300072 China Insititute of Medical Equipment Academy of Military Medical Sciences Tianjin 300161 China

The colloidal crystal template or opal with a closed-packed face-centered cubic （fcc） lattice was prepared from monodisperse polystyrene （PS） spheres by vertical sedimentation. The template provided void space for infiltration of monomer precursor composed of acrylate acid, acrylamide and ammonium-persulfate, as well as microgel from the subsequent copolymerization. The sample was immersed in dimethylbenzene for completely removing PS spheres to form PAM inverse opal hydrogels （IOHPAM） or PAM/PAA inverse opal hydrogels （IOHPAM/PAA） photonic crystals. The PS spheres were replaced by air spheres, which interconnected each other through the windows. The study of responses to pH show that there are two peaks for both IOHPAM and IOHPAM/PAA films, but the IOHPAM/PAA peaks shift to higher pH, and the peaks are independent with the AA content.

关键词： Photonic crystal pH response PAM/PAA Opal Inverse opal hydrogel

经脐单孔腔镜下应用自制双孔缝合针治疗小儿腹股沟斜疝

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四川医学 2011年第4期32卷 543-545页

作者：刘建张勇祝东强刘恒成都市第五人民医院外一科四川成都611130

目的探讨自制双孔针+单孔腹腔镜技术在小儿腹股沟斜疝手术中的临床意义。方法对36例腹股沟斜疝患儿采用自制双孔针+Wolf-H型镜,行经脐单孔腹腔镜下疝囊高位结扎术,现对患儿的临床治疗资料进行回顾性分析。结果全组均在经脐单孔腹腔镜下... 详细信息

目的探讨自制双孔针+单孔腹腔镜技术在小儿腹股沟斜疝手术中的临床意义。方法对36例腹股沟斜疝患儿采用自制双孔针+Wolf-H型镜,行经脐单孔腹腔镜下疝囊高位结扎术,现对患儿的临床治疗资料进行回顾性分析。结果全组均在经脐单孔腹腔镜下完成疝囊高位结扎术,单侧手术时间8～10min,平均8.7min,双侧手术时间12～18min,平均15.1min。术后均无局部血肿、阴囊水肿、阴囊积气、切口感染及皮下异物感。术后无疝复发,腹部未见明显瘢痕。结论经脐单孔腹腔镜下应用自制双孔缝合针治疗小儿腹股沟斜疝,除具备普通腹腔镜手术的优点外,具有创伤更小,美容效果更佳的优势,是小儿疝外科的一个发展方向。

关键词：自制双孔缝合针单孔腹腔镜(Wolf-H型镜) 小儿腹股沟斜疝