作者机构:
[Mei, Lei; Yuan, Liyong; Chai, Zhifang; Liu, Kang; Yu, Jipan] Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.;[Zhao, Yubao; Chen, Siyu] Univ South China, Coll Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.;[Chai, Zhifang] Chinese Acad Sci, Inst Ind Technol, Engn Lab Adv Energy Mat, Ningbo 315201, Peoples R China.
通讯机构:
[Mei, Lei] C;Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.
关键词:
1,6-addition;Diarylmethane;p-QMs;Uranyl
摘要:
A direct 1,6-addition route of p-QMs to synthesize substituted diarylmethanes catalyzed by uranyl ion was developed. In our approach, the salient feature of this transformation is that abundant, underexploited, neglected and sequestrable depleted uranium made the reaction more sustainable. Moreover, diarylmethane derivatives were delivered in moderate to high yields with broad scope and functional group tolerance. Facile operation and mild conditions offer a practical and attractive protocol. (C) 2020 Elsevier Ltd. All rights reserved.
作者机构:
[Zhao, Yu-Bao; Zhang, Xiao-Lin] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Mei, Lei; Zhang, Xiao-Lin; Hu, Kong-Qiu; Chai, Zhi-Fang; Shi, Wei-Qun] Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.;[Wang, Yi-Tong] China Int Engn Consulting Corp, Beijing 100089, Peoples R China.
通讯机构:
[Zhao, Yu-Bao] U;[Shi, Wei-Qun] C;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.
摘要:
<![CDATA[We report five novel uranyl coordination polymers, [(CH_(3))_(2)NH_(2)]UO_(2)(BTPCA) (<b>1 ), [(CH_(3))_(2)NH_(2)]UO_(2)(BTPCA) (<b>2 ), [(CH_(3))_(2)NH_(2)]_(2)[UO_(2)(BTPCA)][UO_(2)(BTPCA)]·(H_(2)O)_(5.5) (<b>3 ), [(CH_(3))_(2)NH_(2)]_(2)(UO_(2))_(2)(BTPCA)_(2)·(H_(2)O)_(3) (<b>4 ), and [(CH_(3))_(2)NH_(2)]UO_(2)(BTPCA) (<b>5 ), by the utilization of semirigid ligand 1,1′,1″-(benzene-1,3,5-triyl)tripiperidine-4-carboxylic acid (H_(3)BTPCA) and uranyl nitrate through solvothermal reactions. Single-crystal X-ray diffraction analysis reveals that the five compounds share a similar structure composition and local coordination mode to the exclusion of disordered water or DMF molecules. Each UO_(2)(COO)_(3)~(–) motif is connected to six neighboring units through three BTPCA~(3–) ligands, generating an infinite uranyl honeycomb (6, 3) net. The structures of all the five compounds consist of 2D honeycomb nets of various degrees of distortions, which are induced by the flexibility of piperidine rings. The dimethylamine cations and solvent molecules fill in the space between layers. Therefore, these five compounds are isomers in a broad sense. Notably, both compounds <b>3 and <b>4 possess 2-fold interpenetrated structures. For compound <b>5 , the distance between the neighboring 2D honeycomb nets is 7.253 ?. This is the largest distance between the 2D honeycomb nets in uranyl-based coordination polymers, to the best of our knowledge. In addition, compounds <b>1 , <b>2 , and <b>4 are also characterized by infrared spectroscopy (IR), thermogravimetric analysis (TG), powder X-ray diffraction (PXRD), and luminescence properties.]]>
作者机构:
[Zhao, Yubao; Qiu, Liang; Li, Hui; Fan, Zao; Zhai, Wei] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Hoffmann, Michael R.; Zhao, Yubao] CALTECH, Linde Robinson Lab, Pasadena, CA 91125 USA.
通讯机构:
[Zhao, Yubao] U;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.
摘要:
BiOBr samples with different facets were prepared and used for photocatalytic reduction of hexavalent chromium under visible light. The results reveal that BiOBr dominated with {110} facets giving a specific rate constant 3 times as high as BiOBr with {001} facets, and its much stronger internal electric field was believed to be the main reason.
摘要:
Meningococcal disease is a fatal illness of sudden onset caused by Neisseria meningitides. Meningococcal capsular polysaccharide (CPS) is a major virulence factor that generally does not induce immunological memory. Conjugation with a carrier protein can significantly increase the immunogenicity of CPS and induce immunological memory. However, it is highly desired to optimize the CPS-specific immunogenicity of the conjugate vaccine. Although adjuvant has been widely used to improve the immunogenicity of antigens, co-administration and conjugation of adjuvant with the conjugate vaccine has rarely been investigated. As a stimulator of humoral and cellular immunity, beta-glucan can activate macrophages and trigger intracellular processes to secrete cytokines initiating inflammatory reactions. In the present study, a conjugate vaccine (CPS-TT) was generated by conjugation of tetanus toxoid (TT) with meningococcal group Y CPS. CPS-TT was further conjugated with beta-glucan to generate CPS-TT-G. Immunization with CPS-TT-G led to an 8.2-fold increase in the CPS-specific IgG titers as compared with CPS-TT. Presumably, conjugation of beta-glucan ensured the two components to simultaneously reach the antigen presenting cells and stimulate the immune response. In contrast, co-administration of beta-glucan suppressed the CPS-specific immunogenicity of CPS-TT. Thus, conjugation of beta-glucan is an effective strategy to markedly improve the CPS-specific immunogenicity of the conjugate vaccine. (C) 2015 Elsevier Ltd. All rights reserved.
通讯机构:
[Zhao, Yubao] U;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.
摘要:
Rod-shaped rutile TiO2 nanocrystals with various aspect ratios were prepared by a two-step wet-chemical method, and their photocatalytic performance for the reduction of uranyl ions under UV irradiation was investigated. Results show that there is an obvious difference between their specific activities based on equal surface area; rutile TiO2 nanorods with a moderate aspect ratio exhibited the best activity. Different occupation of {111} and {110} facets and a synergistic effect between them are proposed to explain the activity order.