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901.
合成了配合物Bi[S2P(OC6H4But-p)2]3,通过元素分析、红外光谱、紫外-可见光谱、热重分析和X-射线衍射法进行了结构表征。该晶体属于单斜晶系,C2/c空间群;晶胞参数为:a=30.907(5),b=12.7421(9),c=20.287(2),α=90.00°,β=120.925(18)°,γ=90.00°,V=6853.7(19)3,Dc=1.338g/cm3,Z=4,F(000)=2804,μ(Mo Kα)=2.869mm-1,S=1.062,(Δ/σ)max=0.001,R1=0.0621,wR2=0.1906(I>2σ(I))。晶体结构研究表明,配合物中的(p-ButC6H4O)2PS2-为双齿配体,Bi(III)原子与3个配体(p-ButC6H4O)2PS2-的6个S原子配位形成了畸变八面体构型,分子通过C3—H3…O3氢键形成了一维链状结构。 相似文献
902.
Lijun Zhang Qun He Yin Jiang Xun Hu Aimin Yu 《International journal of environmental analytical chemistry》2013,93(11):1250-1261
A new ionic liquid modified silica gel sorbent was prepared from the reaction of active silica gel with N-3-(-3-triethoxysilylepropyl)-3-methylimidazolium chloride ([(TESP)MIm]Cl). This sorbent was exploited as solid phase extractant for separation and preconcentration of metal ions prior to their determination by inductively coupled plasma atomic emission spectrometry (ICP-AES). It was found that it can selectively adsorb Fe(Ш). Identification of the surface modification was performed on the basis of FT-IR. Experimental conditions for effective adsorption of trace Fe(Ш) were optimised using both batch and column procedures. At pH 3, Fe(Ш) could be quantitatively adsorbed and completely eluted by using 2?mL of 0.1?mol?L?1 of HCl. 150?mL of sample solution was adopted as the maximum sample volume and a high enrichment factor of 75 was obtained. Most common coexisting ions did not interfere with the separation and preconcentration of Fe(Ш) at optimal conditions. The maximum static adsorption capacity of the sorbent was 37.0?mg?g?1. The detection limit of the present method was 0.48?µg?L?1, and the relative standard deviation (R. S. D.) was lower than 1.7%. The method was successfully applied to the preconcentration of trace Fe(Ш) in biological and natural water samples with satisfactory results. 相似文献
903.
Fan Yang Hongmei Yang Baozhu Tian Jinlong Zhang Dannong He 《Research on Chemical Intermediates》2013,39(4):1685-1699
Mo and C co-doped TiO2 photocatalysts were successfully prepared by a calcination–hydrothermal method. The catalysts were characterized by XRD, XPS, DRS, FTIR, and Raman spectroscopy. Results from photocatalysis showed that 1%Mo–C4/TiO2 had excellent visible light photocatalytic activity. This may be ascribed not only to the Mo and C doping but also to synergism between the Mo and C. 相似文献
904.
Suhang He Chan Zhou Haibo Zhang Xiaohai Zhou 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(3-4):333-344
Binding behaviors of cucurbit[6]uril (CB[6]) and cucurbit[7]uril (CB[7]) with a series of bis-pyridinium compounds N, N’-hexamethylenebis(1-alkyl-4-carbamoyl pyridinium bromide) (HBPB-n) (alkyl chain length, n = 6, 8 and 10) guests were investigated using 1H-NMR, ESI–MS and single crystal X-ray diffraction methods. The results show that CB[6] and CB[7] can form [2]pseudorotaxanes with HBPB-n easily. When increasing the length of tail alkyl chain, the binding site of CB[6] at guest molecules changed from the tail to the middle part, while CB[7] remained located over the tail chain. As CB[6] and CB[7] were added in HBPB-8 aqueous solution, a [3]pseudorotaxane was formed by the inclusion of the internal middle site in CB[6] and the tail chain in CB[7]. 相似文献
905.
Jian‐Nan Xiang Li‐Hui Jiang Chao‐Yue Chen Zhi‐ying Fu Jun‐Fei Duan Xiao‐Xiao He 《Journal of carbohydrate chemistry》2013,32(7):595-614
New retinoyl sugar derivatives of 13‐cis‐retinoic acid were synthesized in three ways in this paper in order to enhance pharmacal effects, especially antiproliferative activities of 13‐cis‐retinoic acid. Their structures were confirmed by IR, 1H‐NMR, 13C‐NMR, and MS spectra and their antiproliferative activities were determined in vitro using human cancer lines. Results showed that some compounds possessed potential antitumor activities. 相似文献
906.
Yaoyao Zhang Xiaoyan Wu Ye Lin Dan Wang Chunming Zhang Dannong He 《Journal of Sol-Gel Science and Technology》2013,68(2):169-174
LiNi1/3Co1/3Mn1/3O2 was prepared by a modified sol–gel method, selecting ethylene diamine tetraacetic acid and citric acid as the co-chelating agent. The mole ratios of ethylene diamine tetraacetic acid (EDTA) to metal ion (Mn+) were 0:1, 1:1 and 2:1. The obtained samples were characterized by XRD, BET and SEM. The XRD showed that LiNi1/3Co1/3Mn1/3O2 had good crystallinity and well-ordered layered structure. After calcined at 850 °C, the LiNi1/3Co1/3Mn1/3O2 particles exhibited a three-dimensional space network structure, which was greatly correlated with the ratio of EDTA to metal ion. The LiNi1/3Co1/3Mn1/3O2 obtained from a mole ratio of 1:1 (EDTA:Mn+) had the best electrochemical performance. The reversible capacities were reached 168 and 100 mAh/g at 1C and 10C discharge rate, respectively. The result of the cycling performance showed a high capacity maintenance ratio of 89.3 % at 1C and 25 °C after 50 cycles. The further electrochemical performance was evaluated by electrochemical impedance spectroscopy and cyclic voltammetry. 相似文献
907.
Pingting He Jie Tao Xianli Huang Jianjun Xue 《Journal of Sol-Gel Science and Technology》2013,68(2):213-218
Nitrogen doped TiO2 (N-TiO2) nanoparticles with about 30 nm in size were produced by a sol–gel method and characterized respectively by UV–vis, X-ray diffraction (XRD), Transmission electron microscopy, X-ray photoelectron spectroscopy (XPS). Their photocatalytic antibacterial properties were evaluated by the antibacterial ratio against Escherichia coli in dark and under simulated sunlight respectively. The XRD pattern showed that the doped nano-TiO2 was mainly composed of anatase phase. The XPS spectra of the N-TiO2 sample indicated that TiO2 was doped by nitrogen atom. The nitrogen doping created a new N 2p state slightly above the valence band top consists of O 2p state, and this pushes up the valence band top and decreased the band gap. Which leaded to the absorption edge was red-shifted to the visible light region of UV–vis spectra of nitrogen doped nano-TiO2 comparing with pure nano-TiO2. The antibacterial percentage of N-TiO2 against E. coli reached to 90 % under simulated sunlight for 2 h, which was much better than that in dark, also than that of pure nano-TiO2. The photo-catalytic antibacterial activity was activated under visible light. The structure and integrity of cell wall and cell membrane were destructed, and even caused the bacteria death. 相似文献
908.
Li Zhang Li Tong Zhang Jing He Zhi Jun Lin Yan Jiang Li Fu Chen 《Journal of Sol-Gel Science and Technology》2013,68(1):150-154
Aluminum nitride (AlN) fibers were prepared from alumina gel fibers and by heat-treatment in ammonia. The influence of silica on the formation of AlN was investigated. It was shown that phase transformation of alumina (γ-Al2O3 to α-Al2O3) and nitridation reaction took place above 1,100 °C for pure alumina fiber. The addition of a small amount of silica (3 wt%) suppressed the formation of α-Al2O3 and preserved the highly reactive metastable alumina, and nitridation rate was enhanced. Fine grain (~20 nm) AlN fibers were obtained for pyrolysis at 1,150–1,250 °C for 3 h in ammonia, and AlN was identified as the sole crystalline phase. 相似文献
909.
Li‐Wei Zhao Hui‐Min Shi Zhe An Jiu‐Zhao Wang Prof. Jing He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(37):12350-12355
Effectively enhancing the enantioselectivity is a persistent challenge in heterogeneous asymmetric catalysis. Here, the validity of a layered double hydroxides (LDH) nanosheet as an efficient planar substituent to enhance the enantioselectivity has been investigated theoretically; first in vanadium‐catalyzed asymmetric epoxidation of allylic alcohols, and then in zinc‐catalyzed direct asymmetric aldol addition. The computational predication is further confirmed experimentally in zinc‐catalyzed direct asymmetric aldol addition by controlling the location of catalytic sites. 相似文献
910.
Yang Xu Ming Wu Yang Liu Prof. Dr. Xi‐Zeng Feng Prof. Dr. Xue‐Bo Yin Prof. Xi‐Wen He Prof. Yu‐Kui Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(7):2276-2283
Carbon dots (Cdots) are an important probe for imaging and sensing applications because of their fluorescence property, good biocompatibility, and low toxicity. However, complex procedures and strong acid treatment are often required and Cdots suffer from low photoluminescence (PL) emission. Herein, a facile and general strategy using carbonization of precursors and then extraction with solvents is proposed for the preparation of nitrogen‐doped Cdots (N‐Cdots) with 3‐(3,4‐dihydroxyphenyl)‐L ‐alanine (L ‐DOPA), L ‐histidine, and L ‐arginine as precursor models. After they are heated, the precursors become carbonized. Nitrogen‐doped Cdots are subsequently extracted into N,N′‐dimethylformamide (DMF) from the carbogenic solid. A core–shell structure of Cdots with a carbon core and the oxygen‐containing shell was observed. Nitrogen has different forms in N‐Cdots and oxidized N‐Cdots. The doped nitrogen and low oxidation level in N‐Cdots improve their emission significantly. The N‐Cdots show an emission with a nitrogen‐content‐dependent intensity and Cdot‐size‐dependent emission‐peak wavelength. Imaging of HeLa cells, a human cervical cancer cell line, and HepG2 cells, a human hepatocellular liver carcinoma line, was observed with high resolution using N‐Cdots as a probe and validates their use in imaging applications and their multicolor property in the living cell system. 相似文献