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941.
Wang Xuegang Li Peng Liu Yajie Sun Zhanxue Chai Liyuan Min Xiaobo Guo Yadan Zheng Zhihong Ke Yong Liang Yanjie 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(2):1033-1040
Journal of Radioanalytical and Nuclear Chemistry - We evaluated the effectiveness of bioleaching uranium from a low-grade carbonaceous-siliceous-argillaceous type uranium ore using an indigenous... 相似文献
942.
Guo Xue Feng Yurun Ma Li Yu Jincheng Jing Jie Gao Dezhi Khan Adil Saleem Gong Hongyu Zhang Yujun 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):397-407
Nickel hydroxide solubility has been studied in this work in different cementitious systems. Our results indicate that once Glenium® 27, cement superplasticizer admixture, is added to water and then mixed with cement, this polymeric material is stabilized and not released back to the aqueous solution, with negligible effects on the mobility of nickel. Contrary to that, when Glenium® 27 is added directly in solution at high dosages, an important effect is observed on nickel behaviour. Thermodynamic calculations indicate that the effect of such component on Ni is likely the effect that other small organics could have over this element.
相似文献943.
Bifunctional Fluorescent Probe for Sequential Sensing of Thiols and Primary Aliphatic Amines in Distinct Fluorescence Channels 下载免费PDF全文
Meiyu Huang Prof. Dr. Lingliang Long Ning Wang Xiangqi Yuan Siyu Cao Aihua Gong Prof. Dr. Kun Wang 《化学:亚洲杂志》2018,13(5):560-567
Thiols and primary aliphatic amines (PAA) are ubiquitous and extremely important species in biological systems. They perform significant interplaying roles in complex biological events. A single fluorescent probe differentiating both thiols and PAA can contribute to understanding the intrinsic inter‐relationship of thiols and PAA in biological processes. Herein, we rationally constructed the first fluorescent probe that can respond to thiols and PAA in different fluorescence channels. The probe exhibited a high selectivity and sensitivity to thiols and PAA. In addition, it displayed sequential sensing ability when the thiols and PAA coexisted. The application experiments indicated that the probe can be used for sensing thiols and PAA in human blood serum. Moreover, the fluorescence imaging of endogenous thiols and PAA as well as antihypertensive drugs captopril and amlodipine in living cells were successfully conducted. 相似文献
944.
Back Cover: Promoted Fixation of Molecular Nitrogen with Surface Oxygen Vacancies on Plasmon‐Enhanced TiO2 Photoelectrodes (Angew. Chem. Int. Ed. 19/2018) 下载免费PDF全文
945.
Xiuting Chen Qingnuan Li Yu Gong 《Journal of the American Society for Mass Spectrometry》2018,29(12):2327-2332
Ligated tetrapositive metal ions are rare gas-phase species which tend to form complexes with lower charges due to the high 4th ionization energies of metals. We report the observation of tetrapositive Zr(TMPDA)34+ and Zr(TMOGA)34+ complexes in the gas phase by electrospray ionization of Zr(ClO4)4/TMPDA and Zr(ClO4)4/TMOGA mixtures. The Zr4+ center in both complexes is coordinated by nine atoms from three neutral diamide ligands forming nine-coordinate twisted tricapped trigonal prismatic geometry on the basis of DFT calculations. Collision-induced dissociation of both complexes resulted in the loss of protonated ligands to form tripositive Zr(TMPDA)(TMPDA-H)3+ and Zr(TMOGA)(TMOGA-H)3+ products which retain the IV oxidation state of zirconium at the cost of charge reduction from 4+ to 3+ of the whole complexes. The very high 4th ionization energy of zirconium (34.34 eV) makes tetrapositive zirconium complex the most challenging tetracation to be stabilized against charge reduction in the gas phase to date. 相似文献
946.
947.
Zirconium–Porphyrin‐Based Metal–Organic Framework Hollow Nanotubes for Immobilization of Noble‐Metal Single Atoms 下载免费PDF全文
Ting He Dr. Shuangming Chen Bing Ni Yue Gong Zhao Wu Prof. Li Song Prof. Lin Gu Prof. Wenping Hu Prof. Xun Wang 《Angewandte Chemie (International ed. in English)》2018,57(13):3493-3498
Single atoms immobilized on metal–organic frameworks (MOFs) with unique nanostructures have drawn tremendous attention in the application of catalysis but remain a great challenge. Various single noble‐metal atoms have now been successfully anchored on the well‐defined anchoring sites of the zirconium porphyrin MOF hollow nanotubes, which are probed by aberration‐corrected scanning transmission electron microscopy and synchrotron‐radiation‐based X‐ray absorption fine‐structure spectroscopy. Owing to the hollow structure and excellent photoelectrochemical performance, the HNTM‐Ir/Pt exhibits outstanding catalytic activity in the visible‐light photocatalytic H2 evolution via water splitting. The single atom immobilized on MOFs with hollow structures are expected to pave the way to expand the potential applications of MOFs. 相似文献
948.
The nickel catalyzed reductive coupling of allylic carbonates with chloro-cyclotryptamine analogs to construct sterically congested all C(sp3) quaternary centers has been achieved with emphasis on the substrate scope. And the using of dienyl methyleneyl carbonates coupling with a variety of tertiary alkyl halides furnished the dienylated products improved the reaction's applicability. 相似文献
949.
Zufu?Yao Xin?YangEmail author Xiaobo?Liu Yaqi?Yang Yangjian?Hu Zijian?ZhaoEmail author 《Mikrochimica acta》2018,185(1):70
An electrochemical quercetin (QR) sensor is described that is based on the use of magnetic reduced graphene oxide (MrGO) incorporated into a molecularly imprinted polymer (MIP) on the surface of a screen-printed electrode (SPE). The MrGO consists of reduced graphene oxide (rGO), magnetite (Fe3O4) and silver nanoparticles (Ag). The analyte (QR) is electrostatically adsorbed on the surface of the MrGO. Finally, the MIP was deposited via in-situ polymerization. The composite was characterized by X-ray diffraction, Fourier transform infrared spectroscopy and Vibrating sample magnetometry. The morphologies and electrochemical properties of different electrodes were characterized by Field emission scanning electron microscopy, Electrochemical impedance spectroscopy and differential pulse voltammetry. Under optimal conditions, the modified electrode has a linear response in the 20 nM to 250 μM QR concentration range. The limit of detection is 13 nM (at an S/N ratio of 3). The electrode is selective, stable, regenerable and reliable. It was applied to the determination of QR in spiked pharmaceutical samples and gave satisfactory results. 相似文献
950.
Influence of Functional Groups and Modi cation Sites of Metal-Organic Frameworks on CO2/CH4 Separation: A Monte Carlo Simulation Study 下载免费PDF全文
In order to explore the in uence of modification sites of functional groups on landfill gas (CO2/CH4) separation performance of metal-organic frameworks (MOFs), six types of organic linkers and three types of functional groups (i.e. -F, -NH2, -CH3) were used to construct 36 MOFs of pcu topology based on copper paddlewheel. Grand canonical Monte Carlo simulations were performed in this work to evaluate the separation performance of MOFs at low (vacuum swing adsorption) and high (pressure swing adsorption) pressures, respectively. Simulation results demonstrated that CO2 working capacity of the unfunctionalized MOFs generally exhibits pore-size dependence at 1 bar, which increases with the decrease in pore sizes. It was also found that -NH2 functionalized MOFs exhibit the highest CO2 uptake due to the enhanced Coulombic interactions between the polar -NH2 groups and the quadrupole moment of CO2 molecules, which is followed by -CH3 and -F functionalized ones. Moreover, positioning the functional groups -NH2 and -CH3 at sites far from the metal node (site b) exhibits more significant enhancement on CO2/CH4 separation performance compared to that adjacent to the metal node (site a). 相似文献