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61.
62.
Jian Fei Yang Xiu Fang Bian Mei Ling Yuan Yan Wen Bai Yang Liu Jun Peng Fan Xiao Qian Lu Kai Kai Song 《Journal of Sol-Gel Science and Technology》2013,67(2):362-367
The metallic glass/titanium dioxide powders (MG/TiO2) with enhanced photocatalytic oxidation activity were synthesized, which exhibit a higher efficiency in decolorizing methylene blue solutions (MB). Compared with the pure TiO2 and crystalline alloy/TiO2 (CA/TiO2) under the same circumstances, its degradation rate was 60 % and 30 % higher, respectively. Furthermore, compared with the CA/TiO2, the MG/TiO2 photocatalytic rate was three times faster when decolorizing MB. Considering the excellent intrinsic high-performance photocatalytic degradation under visible light irradiation, these novel powders were proven to have potential applications in water purification industry. 相似文献
63.
Dr. Yan‐Yan Fu Dr. Cheng‐Xiong Yang Prof. Dr. Xiu‐Ping Yan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(40):13484-13491
The unique features of high porosity, shape selectivity, and multiple active sites make metal–organic frameworks (MOFs) promising as novel stationary phases for high‐performance liquid chromatography (HPLC). However, the wide particle size distribution and irregular shape of conventional MOFs lead to lower column efficiency of such MOF‐packed columns. Herein, the fabrication of monodisperse MOF@SiO2 core–shell microspheres as the stationary phase for HPLC to overcome the above‐mentioned problems is reported. Zeolitic imidazolate framework 8 (ZIF‐8) was used as an example of MOFs due to its permanent porosity, uniform pore size, and exceptional chemical stability. Unique carboxyl‐modified silica spheres were used as the support to grow the ZIF‐8 shell. The fabricated monodisperse ZIF‐8@SiO2 packed columns (5 cm long × 4.6 mm i.d.) show high column efficiency (23 000 plates m?1 for bisphenol A) for the HPLC separation of endocrine‐disrupting chemicals (bisphenol A, β‐estradiol, and p‐(tert‐octyl)phenol) and pesticides (thiamethoxam, hexaflumuron, chlorantraniliprole, and pymetrozine) within 7 min with good relative standard deviations for 11 replicate separations of the analytes (0.01–0.39, 0.65–1.7, 0.70–1.3, and 0.17–0.91 % for retention time, peak area, peak height, and half peak width, respectively). The ZIF‐8@SiO2 microspheres combine the advantages of the good column packing properties of the uniform monodisperse silica microspheres and the separation ability of the ZIF‐8 crystals. 相似文献
64.
Dr. Ming‐Hua Xie Xiu‐Li Yang Dr. Yabing He Prof. Dr. Jian Zhang Prof. Dr. Banglin Chen Prof. Dr. Chuan‐De Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(42):14316-14321
A simple strategy to rationally immobilize metalloporphyrin sites into porous mixed‐metal–organic framework (M′MOF) materials by a metalloligand approach has been developed to mimic cytochrome P450 monooxygenases in a biological system. The synthesized porous M′MOF of [Zn2(MnOH–TCPP)(DPNI)] ? 0.5 DMF ? EtOH ? 5.5 H2O ( CZJ‐1 ; CZJ=Chemistry Department of Zhejiang University; TCPP=tetrakis(4‐carboxyphenyl)porphyrin); DPNI=N,N′‐di(4‐pyridyl)‐1,4,5,8‐naphthalenetetracarboxydiimide) has the type of doubly interpenetrated cubic α‐Po topology in which the basic Zn2(COO)4 paddle‐wheel clusters are bridged by metalloporphyrin to form two‐dimensional sheets that are further bridged by the organic pillar linker DPNI to form a three‐dimensional porous structure. The porosity of CZJ‐1 has been established by both crystallographic studies and gas‐sorption isotherms. CZJ‐1 exhibits significantly high catalytic oxidation of cyclohexane with conversion of 94 % to the mixture of cyclohexanone (K) and cyclohexanol (A) (so‐called K–A oil) at room temperature. We also provided solid experimental evidence to verify the catalytic reaction that occurred in the pores of the M′MOF catalyst. 相似文献
65.
Transition from π Radicals to σ Radicals: Substituent‐Tuned Cyclization of Hydrazonyl Radicals
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Xiu‐Long Yang Prof. Dr. Wei Yu Prof. Dr. Bing Han 《Angewandte Chemie (International ed. in English)》2014,53(12):3158-3162
Hydrazonyl radicals are known for their π‐electronic structures; however, their σ‐electronic structures have not been reported as yet. Herein, we show that readily accessible β,γ‐ and γ,δ‐unsaturated N‐trichloroacetyl and N‐trifluoroacetyl hydrazones can be conveniently converted into hydrazonyl σ radicals, which subsequently undergo 5‐exo‐trig radical cyclization at the N1 or N2 atom to form pyrazolines and azomethine imines, respectively. 相似文献
66.
Inside Cover: Uniaxial Movements of a Metal–Cyanide Framework Switched by Weak Interactions through Dehydration and Rehydration (Chem. Eur. J. 27/2014)
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67.
Tailoring 3,3′‐Dihydroxyisorenieratene to Hydroxystilbene: Finding a Resveratrol Analogue with Increased Antiproliferation Activity and Cell Selectivity
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Yan‐Fei Kang Wen‐Jing Yan Ting‐Wen Zhou Dr. Fang Dai Dr. Xiu‐Zhuang Li Xia‐Zhen Bao Yu‐Ting Du Cui‐Hong Yuan Hai‐Bo Wang Xiao‐Rong Ren Dr. Qiang Liu Dr. Xiao‐Ling Jin Prof. Dr. Bo Zhou Prof. Dr. Jie Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):8904-8908
Four novel compounds were designed by “tailoring” 3,3′‐dihydroxyisorenieratene (a natural carotenoid) based on an isoprene unit retention truncation strategy. Among them, the smallest molecule 1 (2,3,6,2′,3′,6′‐hexamethyl‐4,4′‐dihydroxy‐trans‐stilbene) was concisely synthesized in a one‐pot Stille–Heck tandem sequence, and surfaced as a promising lead molecule in terms of its selective antiproliferative activity mediated by blocking the NCI‐H460 cell cycle in G1 phase. Additionally, theoretical calculations and cell uptake experiments indicate that the unique polymethylation pattern of compound 1 significantly induces a conformational change shift out of planarity and increases its cell uptake and metabolic stability. The observation should be helpful to rationally design resveratrol‐inspired antiproliferative agents. 相似文献
68.
Jun‐Jie Shen Prof. Shou‐Fei Zhu Dr. Yan Cai Huan Xu Xiu‐Lan Xie Prof. Qi‐Lin Zhou 《Angewandte Chemie (International ed. in English)》2014,53(48):13188-13191
An iron‐catalyzed asymmetric intramolecular cyclopropanation was realized in high yields and excellent enantioselectivity (up to 97 % ee) by using the iron complexes of chiral spiro‐bisoxazoline ligands as catalysts. The superiority of iron catalysts exhibited in this reaction demonstrated the potential abilities of this sustainable metal in asymmetric carbenoid transformation reactions. 相似文献
69.
哈茨木霉CGMCC 2979生物转化栀子中的京尼平苷制备京尼平 总被引:1,自引:0,他引:1
采用微生物直接转化药材的方法,将栀子中的京尼平苷转化为京尼平,无需糖苷酶和京尼平苷的制备. 在培养温度为30 ℃,pH 6.1以及栀子载量为80 g/L的条件下,48 h京尼平苷的转化率为97.8%. 转化后的京尼平通过XAD-16N大孔树脂偶联硅胶层析的方法,制备得到纯度大于95%的京尼平,收率为62.3%. 在催化、转化机制研究中,从哈茨木霉CGMCC2979的发酵液中分离得到了分子量为74.4 kDa的京尼平苷β-葡萄糖苷酶,该酶最优催化条件为50 ℃和pH 4.0-5.0. Km和Vmax分别为3.6 mmol/L和775 μmol/h/mg蛋白. 本文提供了一种简便、高效制备京尼平的新方法. 相似文献
70.
Two different eight-arm star-shaped polyhedral oligomeric silsesquioxane (POSS) fluorinated acrylates were synthesized through atom transfer radical polymerization (ATRP) and applied for hydrophobic honeycomb-patterned porous films through the breath figure (BF) method. The structure of polymers was characterized by Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC), and surface analysis was featured by X-ray photoelectron spectroscopy (XPS). Depending on the influences of polymer architectures, solvents utilized, and solution concentrations, honeycomb-patterned porous films were obtained. It could be found that the introduction of fluorine components was a favorable condition for BF formation and chloroform (CHCl3) utilized as solvent with an appropriate concentration of 30 mg/mL was the best condition for these hydrophobic honeycomb-patterned porous films. Meanwhile, the obtained honeycomb films could be retained after long-time preservation in an acid-base condition, which shows a great potential in filtration, cell culture, tissue engineering, and marine antifouling applications. 相似文献