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991.
Li-Jun Li Cheng Wang Yu Qiao Xiao-Yan Yang Xing-Xing Hua Jian-Long Du 《Research on Chemical Intermediates》2014,40(1):413-424
A series of platinum(II) complexes of reduced amino acid esters Schiff bases were synthesized as potential anticancer agents and characterized by 1H NMR, EA, IR, and molar conductivity. These compounds were tested for their DNA interaction with salmon sperm DNA by ultraviolet spectrum and CD spectrum, and their in vitro anticancer activities have been validated against HL-60, KB, BGC-823, and Bel-7402 cell lines by MTT assay. The cytotoxicity of complexes 5d and 5f are better than cisplatin against Bel-7402 cell lines, and show a close cytotoxic effect against HL-60 cell line. 相似文献
992.
993.
Geng Tianfeng Du Chunyu Cheng Xinqun Xu Xing Jian Jiyuan He Xiaoshu Zuo Pengjian Yin Geping 《Journal of Solid State Electrochemistry》2019,23(1):101-108
Journal of Solid State Electrochemistry - Li-rich layered oxide (LrLO) cathode has attracted much attention for Li-ion batteries in recent years due to its superior capacity of exceeding... 相似文献
994.
Tao Yong Cao Yanbing Hu Guorong Chen Pengwei Peng Zhongdong Du Ke Jia Ming Huang Yong Xia Jin Li Luyu Xie Xiaoming 《Journal of Solid State Electrochemistry》2019,23(7):2243-2250
Journal of Solid State Electrochemistry - LiFePO4 cathode material is considered as prospective materials for lithium-ion batteries and attracted great interest because of excellent cyclic... 相似文献
995.
Jared B. Shaw Tzu-Yung Lin Franklin E. LeachIII Aleksey V. Tolmachev Nikola Tolić Errol W. Robinson David W. Koppenaal Ljiljana Paša-Tolić 《Journal of the American Society for Mass Spectrometry》2016,27(12):1929-1936
We provide the initial performance evaluation of a 21 Tesla Fourier transform ion cyclotron resonance mass spectrometer operating at the Environmental Molecular Sciences Laboratory at the Pacific Northwest National Laboratory. The spectrometer constructed for the 21T system employs a commercial dual linear ion trap mass spectrometer coupled to a FTICR spectrometer designed and built in-house. Performance gains from moving to higher magnetic field strength are exemplified by the measurement of peptide isotopic fine structure, complex natural organic matter mixtures, and large proteins. Accurate determination of isotopic fine structure was demonstrated for doubly charged Substance P with minimal spectral averaging, and 8158 molecular formulas assigned to Suwannee River Fulvic Acid standard with root-mean-square (RMS) error of 10 ppb. We also demonstrated superior performance for intact proteins; namely, broadband isotopic resolution of the entire charge state distribution of apo-transferrin (78 kDa) and facile isotopic resolution of monoclonal antibody under a variety of acquisition parameters (e.g., 6 s time-domains with absorption mode processing yielded resolution of approximately 1 M at m/z?=?2700). 相似文献
996.
Ladislav Androvič Jan Bartáček Miloš Sedlák 《Research on Chemical Intermediates》2016,42(6):5133-5145
This mini-review describes recent developments and trends in the area of syntheses and applications of azo compounds, which are planned to act as initiators of radical reactions, particularly polymerizations. The paper reports chemical modifications of well-known initiators (AIBN, etc.) or variants of syntheses of new types of these compounds. The chemical modifications of basic skeletons of azo initiators are discussed in the context with their properties and applications. Also discussed are the contemporary trends in the development of these initiators, particularly in preparation of microparticles and nanoparticles of polymers or hybrid inorganic–organic microparticles and nanoparticles prepared for intentional studies and applications. 相似文献
997.
Nikica Šprem Ivan Babić Domagoj Barišić Delko Barišić 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(1):513-517
The aim of this study was to investigate 137Cs and 40K load in large mammal game species in the mountain forest region of Gorski Kotar in Croatia approximately a quarter of century after the Chernobyl accident. 137Cs and 40K activity were determined by the gamma-spectrometric method in 49 meat samples of five large game species: brown bear (Ursus arctos), wild boar (Sus scrofa), roe deer (Capreolus capreolus), red deer (Cervus elaphus), and chamois (Rupicapra rupicapra). The results indicated that herbivore game species (roe deer, red deer and chamois) show significantly lower 137Cs concentrations than omnivore species (brown bear, wild boar), thereby confirming the hypothesis that different dietary strategy impact caesium concentrations in meat. The measured caesium load in brown bear meat was in the range of two orders of magnitude, while caesium load in wild boar meat was found in the range of one order of magnitude. The estimated effective equivalent dose showed that uptake of the highest caesium doses would be from consumption of omnivore species meat, while much lower doses could be taken in with the consumption of meat from herbivore species. 相似文献
998.
Potassium tantalate (KT) thin films and powders of both K2Ta2O6 (KT pyrochlore) and KTaO3 (KT perovskite) structures were prepared by means of chemical solution deposition method using Si(111) with ZnO and MgO buffer layers as a substrate. The influence of reaction atmosphere on reaction pathway and phase composition for both KT powders, and KT thin films has been studied mainly by means of powder diffraction and infrared spectroscopy. When an oxygen flow instead of static air atmosphere has been used the process of pyrolysis in oxygen runs over much narrower temperature interval (200–300 °C), relatively to air atmosphere (200–600 °C) and almost no (in case of powders), or no (in case of thin films) pyrochlore intermediate phase has been detected in comparison with treatment in air, where the pyrochlore phase is stable at temperatures 500–600 °C (powders). KT perovskite phase starts to crystallize at temperatures 50° and 150 °C lower compared to air atmosphere in case of powders and thin films, respectively. Microstructure formed by near-columnar grains and small grains of equiaxed shape was observed in films treated in oxygen and air atmosphere, respectively. 相似文献
999.
Zhu B Yuan F Li R Li Y Wei Q Ma Z Du B Zhang X 《Chemical communications (Cambridge, England)》2011,47(25):7098-7100
A simple but highly selective colorimetric and ratiometric fluorescent chemodosimeter was designed and synthesized to detect fluoride ions (F(-)) in aqueous solution and living cells by virtue of the strong affinity of F(-) toward silicon. 相似文献
1000.
Maintaining the predictive abilities of multivariate calibration models by spectral space transformation 总被引:1,自引:0,他引:1
Du W Chen ZP Zhong LJ Wang SX Yu RQ Nordon A Littlejohn D Holden M 《Analytica chimica acta》2011,690(1):64-70
In quantitative on-line/in-line monitoring of chemical and bio-chemical processes using spectroscopic instruments, multivariate calibration models are indispensable for the extraction of chemical information from complex spectroscopic measurements. The development of reliable multivariate calibration models is generally time-consuming and costly. Therefore, once a reliable multivariate calibration model is established, it is expected to be used for an extended period. However, any change in the instrumental response or variations in the measurement conditions can render a multivariate calibration model invalid. In this contribution, a new method, spectral space transformation (SST), has been developed to maintain the predictive abilities of multivariate calibration models when the spectrometer or measurement conditions are altered. SST tries to eliminate the spectral differences induced by the changes in instruments or measurement conditions through the transformation between two spectral spaces spanned by the corresponding spectra of a subset of standardization samples measured on two instruments or under two sets of experimental conditions. The performance of the method has been tested on two data sets comprising NIR and MIR spectra. The experimental results show that SST can achieve satisfactory analyte predictions from spectroscopic measurements subject to spectrometer/probe alteration, when only a few standardization samples are used. Compared with the existing popular methods designed for the same purpose, i.e. global PLS, univariate slope and bias correction (SBC) and piecewise direct standardization (PDS), SST has the advantages of implementation simplicity, wider applicability and better performance in terms of predictive accuracy. 相似文献