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Synthesis and properties of tribranched chromophores with triazine and fluorene units

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Chinese Chemical Letters 2011年第10期22卷 1147-1150页

作者： Li Liu Zhi Qiang Zhou Jie Ping Shi chang gui lu Yi Ping Cui Guo Yuan lu Department of Chemistry State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China Advanced Photonics Center Southeast University Nanjing 210096 China

Two tribranched chromophores,1,3,5-triazine as electron deficient core,9,9-dimethylfluorene asπ-conjugated bridge, diphenylamino（4a） and naphthylamino（4b） as electron-donating end-groups,were successfully prepared via Buchwald-Hartwig coupling *** linear photophysical and two-photon absorption（TPA） properties were investigated by absorption, fluorescence and nonlinear transmission method,*** absorption cut-offs of the chromophores are below 550 nm and both chromophores have strong fluorescence *** compound 4a（206.3 GM） exhibits larger TPA cross-section than 4b （57.8 GM） in the femtosecond regime at 800 nm.

关键词： Octupolar molecules Buchwald-Hartwig cross-coupling Photophysical properties TPA cross-section

Two-photon Absorption and Optical Power Limiting Properties of Two Novel Dibenzothiophene-based Chromophores

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Chinese Chemical Letters 2006年第9期17卷 1263-1266页

作者： Jian Wei CHENG Xiao Mei WANG Jin XU chang gui lu Yi Ping CUI Bo LI Shi Xiong QIAN Ping YANG Material Engineering Institute Chemical Department of Suzhou University Suzhou 215021 Department of Electronic Engineering Southeast University Nanjing 210096 Laboratory of Advanced Materials Fudan University Shanghai 200433

Two novel V-shaped symmetric chromophores： E-2,8-bis（4-vinyl-4-carbazol-9-yl）diben- zothiophene （abbreviated as SK-G1） and E-2,8-bis（4-vinyl-4-triphenylamino） dibenzothiophene （abbreviated as ST-G1） have been synthesized and characterized. Their two photon absorption properties were measured by the open-aperture femtosecond Z-scan technique and the nanosecond nonlinear optical transmission （NLT）, respectively, when pumped by Ti： sapphire laser at 750 nm and 800 nm.

关键词： E-2,8-Bis(4-vinyl-4-carbazol-9-yl)dibenzothiophene E-2,8-bis(4-vinyl-4-triphenyl- amino)dibenzothiophene two-photon absorption optical limiting.

Enteroenteroanastomosis near adjacent ileocecal valve in infants

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World Journal of Gastroenterology 2012年第48期18卷 7314-7318页

作者： Wei-Wei Jiang Xiao-Qun Xu Qi-Ming Geng Jie Zhang Huan Chen Xiao-Feng Lv chang-gui lu Wei-Bing Tang Department of Pediatric Surgery Nanjing Children's Hospital Affiliated to Nanjing Medical University

AIM:To investigate the feasibility and the effectiveness of ileoileostomy in the region adjacent to the ileocecal valve,which can retain the ileocecal valve in ***:This is a retrospective review of 48 patients who underwent ileoileostomy in the region adjacent to the ileocecal valve(group 1) and 34 patients who underwent ileocecal resections and ileotransversanastomosis(group 2).Patients were monitored for the time to flatus,resumption of eating,length of hospital stay after surgery,serum total bile acid,vitamin B12 and postoperative ***:The time to flatus,time until resumption of eating and post-operative length of hospital stay showed no statistically significant differences between the two *** total bile acid and vitamin B12were not significantly different between the two groups at post-operative day 1 and day 3,but were significantly decreased at 1 wk after operation in group *** of the patients died or suffered from stomal leak in these two ***,the incidence of diarrhea,intestinal infection,disturbance of acid-base balance and water-electrolytes in group 1 was lower than in group ***:Ileoileostomy in the region adjacent to the ileocecal valve is safe and results in fewer complications than ileotransversanastomosis in infants.

关键词： Ileocecal valve Ileoileostomy Infants

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连铸中间包水口堵塞机理及控制技术的发展

钢铁研究学报 2017年第10期29卷 773-780页

作者：杨明磊程常桂李阳卢海彪周焱金焱武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室湖北武汉430081

中间包水口堵塞问题严重影响连铸正常操作,造成铸坯卷渣、铸坯质量恶化,解决好中间包水口堵塞问题对于稳定连铸生产、提高铸坯质量具有重要意义。结合前人研究成果,总结了不同钢种、脱氧与精炼工艺条件下连铸中间包水口堵塞的机理,评述... 详细信息

中间包水口堵塞问题严重影响连铸正常操作,造成铸坯卷渣、铸坯质量恶化,解决好中间包水口堵塞问题对于稳定连铸生产、提高铸坯质量具有重要意义。结合前人研究成果,总结了不同钢种、脱氧与精炼工艺条件下连铸中间包水口堵塞的机理,评述了钢液中夹杂物的生成、夹杂物向水口内壁面传递、粘附与沉积等因素对水口堵塞的影响机制,分析了各种防止水口堵塞控制技术的特点,提出了改善水口堵塞技术和理论研究方向。

关键词：连铸中间包水口堵塞机理控制技术

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第01期 201-208页

作者： Hui-Feng Wang Wen-Jie Shi Yu-Xin Yang Bao-Xia Dong Tong-Bu lu Di-chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

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Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-Ang Nan Qing Li Xiufang Li Zi-Xiu lu Linzhe Lü Jin Liu luyao Liu Wenjing Wang Wei Wang Daqiang Yuan You-gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-Hui Zhang Zhi-Lai Zhan Guang-lu chang Yan Gao Xia Li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

Numerical studies on four-engine rocket exhaust plume impinging on flame deflectors with afterburning

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Defence Technology（防务技术） 2021年第4期17卷 1207-1216页

作者： Zhi-tan Zhou chang-fang Zhao Chen-yu lu gui-gao Le School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

This paper studies the four-engine liquid rocket flow field during the launching *** threedimensional compressible Navier-Stokes equations and two-equation realizable k-epsilon turbulence model,an impact model is established and flow fields of plume impinging on the two different shapes of flame deflectors,including wedge-shaped flame deflector and cone-shaped flame deflector,are *** finite-rate chemical kinetics is used to track chemical *** simulation results show that afterburning mainly occurs in the mixed *** the region of peak pressure occurs directly under the rocket nozzle,which is the result of the direct impact of exhaust *** with the wedgeshaped flame deflector,the cone-shaped flame deflector has great performance on guiding exhaust *** wedge-shaped and cone-shaped flame deflectors guide the supersonic exhaust plume away from the impingement point with two directions and circumferential direction,*** maximum pressure and temperature on the wedge-shaped flame deflector surface are 37.2%and 9.9%higher than those for the cone-shaped flame *** results provide engineering guidance and theoretical significance for design in flame deflector of the launch platforms.

关键词： Four-engine rocket Afterburning Impinging flow field Different deflectors Numerical simulations

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降低聚丙烯粉料灰分的措施探讨

弹性体 2003年第3期13卷 38-42页

作者：丁长胜陆贵根张世忠锦州石化分公司辽宁锦州121001

分析了影响聚丙烯粉料灰分的因素,介绍了CS 1型高效催化剂体系聚丙烯灰分理论值计算公式,论述了从完善丙烯精制手段、提高丙烯质量、降低催化剂加料量、提高单釜产量诸方面入手,降低聚丙烯粉料灰分,提高产品质量的几项措施。

关键词：聚丙烯粉料灰分聚合催化剂