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Preparation of Pt/K_2La_2Ti_3._(10) and its photo-catalytic activity for hydrogen evolution from methanol water solution

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Science china Chemistry 2006年第2期49卷 162-168页

作者： CUI Wenquan1,3. LIU Li2, FENG Liangrong1, XU Chenghua1, LI Zijian1, Lü Shaojie1 & qiu fali1 1. Chengdu Institute of Organic Chemistry, chinese {3. of sciences, Chengdu 610041, china 2. Chemistry Department, Sichuan University of Science & Engineering, Zigong 643.3., china 3. graduate school of the chinese academy of sciences, Beijing 10003., china correspondence should be addressed to qiu fali 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China 3. graduate school of the chinese academy of sciences Beijing 100039 China 2. Chemistry Department Sichuan University of Science & Engineering Zigong 643033 China

A layered perovskite-type oxide K2La2Ti3.10 was prepared with high-temperature solid-state reaction, and characterized with X-ray diffraction (XRD) and ultraviolet-visible diffuse re-flectance spectroscopy (UV-Vis DRS). Platinum was loaded onto K2La2Ti3.10 as a co-catalyst with different methods. The dispersion of platinum on K2La2Ti3.10 was determined with HOT method. The photocatalytic activity of Pt/K2La2Ti3.10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than Ni/K2La2Ti3.10. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 23..88 μmol·h?1 by Pt(2%)/K2La2Ti3.10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2La_2Ti_3._(10) support

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Study on the coating of nano-scale SiO_2 film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science china Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1,2,3. MEI Xiujuan2, XU Chenghua1 & qiu fali1 1. Chengdu Institute of Organic Chemistry, chinese {3. of sciences, Chengdu 610041, china 2. Sichuan Fire Research Institute of Public Security Ministry, Chengdu 61183., china 3. graduate school of the chinese academy of sciences, Beijing 10003., china correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Sichuan Fire Research Institute of Public Security Ministry 611830 Chengdu China 3. graduate school of the chinese academy of sciences 100039 Beijing China

The coating process of a nano-scale SiO2 film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2film with a thickness of about 5 nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3.or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2p, Mg 2p, Si 2s and O 1s on the coated particles indicate that the coating of the SiO2 nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2-coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2on the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 244.67℃ and 43..13., whose corresponding heat absorption capacities are 412.28 J/g and 3.6.3. J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 243.60℃ with a heat absorption capacity of 221.25 J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

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Kinetics and reaction mechanism of phenol hydroxylation catalyzed by La-Cu_4FeAlCO_3

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Science china Chemistry 2005年第6期48卷 530-537页

作者： CHEN Chunxia1,2, XU Chenghua1, FENG Liangrong1, SUO Jishuan1 & qiu fali1 1. Chengdu Institute of Organic Chemistry, chinese {3. of sciences, Chengdu 610041, china 2. graduate school of the chinese {3. of sciences, Beijing 10003., china 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. graduate school of the chinese {3. of sciences 100039 Beijing China

The present work synthesizes La-Cu4FeAlCO3.catalyst under microwave irradiation and characterizes its structure using XRD and IR techniques. The results show that the obtained La-Cu4FeAlCO3.has a hydrotalcite structure. In the phenol hydroxylation with H2O2 catalyzed by La-Cu4FeAlCO3. the effects of reaction time and phenol/H2O2 molar ratio on the phenol hy-droxylation, and relationships between the initial hydroxylation rate with concentration of the catalyst, phenol, H2O2 and reaction temperature are also investigated in details. It is shown the phenol conversion can reach 50.09% (mol percent) in the phenol hydroxylation catalyzed by La-Cu4FeAlCO3. under the reaction conditions of the molar ratio of phenol/H2O2 1/2, the amount ratio of phenol/catalyst 20, reaction temperature 3.3.K, reaction time 120 min, 10 mL distilled water as solvent. Moreover, a kinetic equation of v = k[La ? Cu 4 FeAlCO 3.][C 6 H 5 OH][H 2 O 2]. and the activation energy of Ea=58.3. kJ/mol are obtained according to the kinetic studies. Due to the fact that the HO-Cu+-OH species are detected in La-Cu4FeAlCO3.H2O2 system by XPS, the new mechanism about the generation of hydroxyl free radicals in the phenol hydroxylation is pro-posed, which is supposed that HO-Cu+-OH species are transition state in this reaction.

关键词： rare earth, hydrotalcite, microwave irradiation, phenol hydroxylation, kinetics, reaction mechanism.

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Small molecule metabolites:discovery of biomarkers and therapeutic targets

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Signal Transduction and Targeted Therapy 2023年第4期8卷 1684-1720页

作者： Shi qiu Ying Cai Hong Yao Chunsheng Lin Yiqiang Xie Songqi Tang Aihua Zhang International Advanced Functional Omics Platform Scientific Experiment CenterHainan General Hospital(Hainan Affiliated Hospital of Hainan Medical University)College of Chinese MedicineHainan Medical UniversityXueyuan Road 3Haikou 571199China graduate school Heilongjiang University of Chinese MedicineHarbin 150040China First Affiliated Hospital Harbin Medical UniversityHarbin 150081China Second Affiliated Hospital Heilongjiang University of Chinese MedicineHarbin 150001China

Metabolic abnormalities lead to the dysfunction of metabolic pathways and metabolite accumulation or deficiency which is wellrecognizedhallmarks of diseases. Metabolite signatures that have close proximity to subject’s phenotypic informative dimension,are useful for predicting diagnosis and prognosis of diseases as well as monitoring treatments. The lack of early biomarkers couldlead to poor diagnosis and serious outcomes. Therefore, noninvasive diagnosis and monitoring methods with high specificity andselectivity are desperately needed. Small molecule metabolites-based metabolomics has become a specialized tool for metabolicbiomarker and pathway analysis, for revealing possible mechanisms of human various diseases and deciphering therapeuticpotentials. It could help identify functional biomarkers related to phenotypic variation and delineate biochemical pathwayschanges as early indicators of pathological dysfunction and damage prior to disease development. Recently, scientists haveestablished a large number of metabolic profiles to reveal the underlying mechanisms and metabolic networks for therapeutictarget exploration in biomedicine. This review summarized the metabolic analysis on the potential value of small-moleculecandidate metabolites as biomarkers with clinical events, which may lead to better diagnosis, prognosis, drug screening andtreatment. We also discuss challenges that need to be addressed to fuel the next wave of breakthroughs.

关键词： diagnosis therapeutic Small

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