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Highly selective synthesis and near-infrared photothermal response of heterometallic double trefoil knot and D-type[2]catenanes

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Science China Chemistry 2025年

作者： Ying Zhao Jian-Xin Yang Yin-Hang Chai Yao He Peng Wang Francisco Aznarez Bo li li-Long dang Lu-Fang Ma College of Chemistry and Chemical Engineering Luoyang Normal University College of Chemical and Pharmaceutical Engineering Nanyang Normal University

The selective construction of sophisticated supramolecular topologies has always attracted the remarkable attention of ***,various molecular knots and catenanes have recently been reported and were obtained either accidentally or by following a previously planned synthetic ***,we introduce a series of supramolecular topologies including double trefoil knot (1),trefoil knot (2) and[2]catenanes (4,5),which were prepared via an elaborated self-assembly strategy by using half-sandwich units based on a flexible pyridyl linker *** formation of all the structures has been confirmed by single crystal X-ray diffraction analysis and NMR spectroscopy,and ***,the central potassium ion of 1 coordinates six oxygen atoms belonging to six amide groups from two trefoil *** double trefoil knot 1 and[2]catenanes 4,5 are stabilized by parallel-displacedπ···πstacking interactions (of interlayer distance 3.34–3.82?) between the pyridyl fraction and phenyl moieties of three ligands L1,and by edge-to-face-type CH···πinteractions (2.64–2.83?) between BiBzIm conjugated planes and phenyl hydrocarbon ***,the addition/removal of potassium ions resulted in topological transformation between the double trefoil knot 1 and the trefoil knot *** addition,the addition of DMF-d7to a methanolic solution of the double trefoil knot 1 induced its structural conversion into the metallamacrocycle *** photothermal studies of 1,4,and 5 showed different photothermal responses in solid and solution ***,the photothermal conversion efficiencies of 4,and 5 were within the limit of 16.8%–45.1%based on different power areas,the number and the fashion ofπ···πstacking interactions can directly affect the photothermal conversion efficiency,and EPR experiments confirmed the recorded results.

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Friction and wear properties of ultra-high molecular mass polyethylene reinforced with Al2O3 nano-particle

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 354-358页

作者： FAN Dong-li XIONG dang-sheng Department of Materials Science & Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials Science & Engineering Nanjing University of Science and Technology Nanjing 210094 China

The ultra-high molecular mass polyethylene (UHMMPE) as an artificial joint acetabular material was filled with nano-powder of Al2O3 of various mass fractions. The effect of Al2O3 mass fraction on the hardness, wetting property and tribological properties of the Al2O3-UHMMPE composites under dry friction sliding against both stainless steel and Ti-6Al-4V alloy was investigated. The morphologies of the worn surfaces of composites were observed with optical microscope. The results show that, wetting property and wear resistance of the composites are improved by filling Al2O3, while the friction coefficient is decreased largely under dry friction as compared with that of the unfilled UHMMPE. This is attributed to the reinforcing function of the nano-powder of Al2O3 in the composites. The wear of UHMMPE is dominated by plowing, plastic deformation and fatigue wear; while the Al2O3-UHMMPE composites are characterized by the mild fatigue wear.

关键词： ultra-high molecular mass polyethylene Al2O3 nano-powder filling modification friction and wear properties artificial joint

When should endovascular gastrointestinal anastomosis transection Glissonean pedicle not be used in hepatectomy?A case report

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World Journal of Clinical Cases 2022年第24期10卷 8742-8748页

作者： Jian Zhao, Yan-li dang Department of Hepatobiliary Surgery The Affiliated Hospital of Yunnan UniversityKunming 650000Yunnan ProvinceChina Department of Obstetrics First People's Hospital of Yunnan ProvinceKunming 650000Yunnan ProvinceChina

BACKGROUND The literature on post-hepatectomy bile duct injury(PHBDI)is limited,lacking large sample retrospective studies and high-quality experience ***,we reported a special case of iatrogenic bile duct injury caused by Glissonean pedicle transection with endovascular gastrointestinal anastomosis(endo-GIA)during a right hepatectomy,analyzed the causes of this injury,and summarized the experience with this *** SUMMARY We present the case of a 66-year-old woman with recurrent abdominal pain and cholangitis due to intrahepatic cholangiectasis(Caroli's disease).Preoperative evaluation revealed that the lesion and dilated bile ducts were confined to the right liver,with right hepatic atrophy,left hepatic hypertrophy,and hilar *** problem can be resolved by performing a standard right *** the operation went well,jaundice occurred soon after the *** bile duct injury was considered after magnetic resonance cholangiopancreatography review,and the second operation were performed 10 d *** the second operation,it was found that the endo-GIA had damaged the lateral wall of the hepatic duct and multiple titanium nails remained in the bile duct *** led to severe stenosis of the duct wall,and could not be ***,the injured bile duct was transected,and a hepatic-jejunal-lateral Roux-Y anastomosis was performed at the healthy part of the left hepatic *** this surgery,the patient had a smooth postoperative recovery,and the total bilirubin gradually decreased to *** patient was discharged 41 d after *** anastomotic stenosis was found at the 6 mo of *** Not all cases are suitable for endo-GIA transection of Glissonean pedicle,especially in cases of intrahepatic bile duct *** caused by endo-GIA is very difficult to repair due to extensive ischemia,which requires special attention.

关键词： Endovascular gastrointestinal anastomosis Glissonean pedicle Hepatectomy Bile duct injury Safety Case report

Electronic Properties of Passive Films Formed on G3 and G30 Nickel-based Alloys in Bicarbonate/Carbonate Buffer Solution

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Chemical Research in Chinese Universities 2011年第2期27卷 304-312页

作者： li dang-guo WANG Jia-dao CHEN Da-rong State Key Laboratory of Tribology School of Mechanical Enginering Tsinghua University Beijing 100084 P. R. China

The electronic properties of passive films formed on G3 and G30 alloys in bicarbonate/carbonate buffer solution were comparatively studied by electrochemical impedance spectra（EIS） and Mott-Schottky analysis, the chemical composition of the passive film formed on G3 alloy was detected by X-ray photoelectron spectroscopy （XPS）. The results show that passive film on G3 alloy had better protection than that on G30 alloy. The transfer resistance, film resistance and diffusion resistance of the passive films on both alloys increased with increasing formation potential, prolonging formation time, increasing pH value, decreasing formation temperature, and decreasing chloride and sulphide ions concentration. Mott-Schottky plot reveals that the passive films on the two alloys show a p-n semi-conductive character. XPS analysis indicates that the passive film on G3 alloy was composed of an inner Cr oxide and an outer Fe, Mo/Ni oxides.

关键词： Nickel-based alloy Electronic property Passive film

Anti-corruption, marketisation and firm behaviours: evidence from firm innovation in China

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Economic and Political Studies 2016年第1期4卷 39-61页

作者： li dang Ruilong Yang School of Economics at Renmin University of China BeijingChina

China has launched an anti-corruption campaign since theEighteenth CPC National Congress, which has exerted widespreadinfluences on Chinese politics and economy. This paper examinesthe effect of the anti-corruption initiative on firm behaviours fromthe perspective of research and development (R&D) investments. Itshows that pursuing political connections and improving innovation are two mutually exclusive alternatives for firm growth inChina. The anti-corruption campaign raises the cost of seeking forpolitical bond and strengthens the incentive for firm *** anti-corruption policies and regulations were issued, R&Dexpenditure in politically connected firms increases significantly;the anti-corruption initiative has positive effects on firm *** research shows that the effects vary with different types offirms. For state-owned enterprises (SOEs), the anti-corruptioninitiative only increases the R&D investments of firms with seniorexecutives who used to serve in the government;while for nonstate-owned enterprises (non-SOEs), this campaign has all-aroundpositive effects on their R&D investments. In the meantime, a heterogeneity at the provincial level is observed: R&D investments offirms with political connections increase more significantly in provinces with more intense anti-corruption efforts. Finally, marketisation also has a role to play. For regions with a more developedmarket economy, anti-corruption increases the innovation of firmswith political connections;whereas in regions with a less developed market economy, this effect is insignificant. This paper provides evidence for the opinion that anti-corruption is favourable toeconomic growth in China. To solve the endogeneity problem, ituses data obtained from the anti-corruption policy experimentsince the Eighteenth CPC National Congress and the difference-indifferences (DID) method to further test the hypotheses.

关键词： Anti-corruption DID firm innovation political connections

Scope and Mechanism on Iridium-f-Amphamide Catalyzed Asymmetric Hydrogenation of Ketones

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Chinese Journal of Chemistry 2018年第9期36卷 851-856页

作者： Zhiqin liang Tilong Yang Guoxian Gu li dang Xumu Zhang Department of Chemistry Southern University of Science and Technology 1088 Xueyuan Rd Nanshan District Shenzhen Guangdong 518055 China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou UniversityShantou Guangdong 515063 China

A series of novel and easily accessed ferrocene-based amino-phosphine-sulfonamide （f-Amphamide） ligands have been developed and ap- plied in Ir-catalyzed asymmetric hydrogenation of aryl ketones, affording the corresponding chiral secondary alcohols with excellent results （up to 〉99% conversion, 〉99% ee and TON up to 200 000）. DFT calculations suggest an activating model involving an alkali cation li.

关键词： aryl ketone asymmetric f-Amphamide hydrogenation iridium

Triterpene Acids from Cynoglossum amabile

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Chemical Research in Chinese Universities 2009年第3期25卷 404-406页

作者： XU Qing-jun ZHANG De-zhi dang li-juan li Kun-ping College of Pharmacy Guangdong Pharmaceutical University Guangzhou 510006 P. R. China

Cynoglossum amabile Stapf et Drumm is widely distributed in southern China, which has been used as an anti-inflammatory, antihepatitis, anticystitis agent in Chinese folk medicine. However, only a few phytochemical researches have been performed . Therefore, a systematic chemical investigation of it was carried out. In this work, we further investigated the chemical constituents and ten compounds were obtained, three of which were triterpene acids.

关键词： Cynoglossum amabile Triterpene acid Amabilic acid

Relationship between cellular radio-sensitivity and naked DNA damage in mammalian cells exposed to heavy ions

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Nuclear Science and Techniques 2009年第6期20卷 349-353页

作者： li Wenjian ZHOU Guangming WANG Zhuanzi li Qiang dang Bingrong WANG Jufang Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

The relationship between deoxyribonucleic acid (DNA) damage and the cell death induced by 12C ions irradiation was examined in four kinds of cells, Melanoma B16, cervical squamous carcinoma HeLa, Chinese hamster V79 and hepatoma SMMC-7721. Cell survival was determined by a colonogenic assay, and the sensitivity was described by D50 (the dose of radiation necessary to reduce the survival to 50%). For all cell lines, D50 ranged from 0.74 Gy to 3.85 Gy, among them B16 was the most radiosensitive to 12C ions, and V79 and HeLa cells had almost the same radio-sensitivity, SMMC-7721 was the last. The induction of deproteinized DNA double-strand breaks induced by 12C ions were measured by pulsed-field gel electrophoresis (PFGE), and the initial yield of the deproteinized DNA dsbs per unit dose was expressed as the DNA double break level (L). A linear dose-response curve was seen for initial DNA dsbs for all cell lines (slopes range from 0.40-0.98 (DSBs/100Mbp/Gy)). V79 was the steepest, B16 was the last. There was an inverse relationship between the initial DNA dsb and D50 if the B16 cell line was not considered, but there was no relativity even excludes the B16 cell line. The present results indicate that there is no relationship between cellular sensitivity and initial DNA dsb, even exclude the effects of chromatin structure.

关键词：哺乳动物细胞 DNA损伤放射敏感性重离子 DNA双链断裂脉冲场凝胶电泳无线蜂窝

Key to the fungus-feeder Phlaeothripinae species from China(Thysanoptera: Phlaeothripidae)

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Zoological Systematics 2014年第3期39卷 313-358页

作者： li-Hong dang Ge-Xia Qiao Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Bio-resources Key Laboratory of Shaanxi Province School of Biological Sciences & Engineering Shaanxi University of Technology

In China, 31 genera and 95 species of fungivorous Phlaeothripinae are recorded here, of which 7 species are newly recorded and illustrated. An illustrated identification key to the 94 species is also provided, togethe... 详细信息

关键词： Key Phlaeothripinae fungus-feeder China.