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921.
Chunxiao Feng Guangqing Xu Haipeng Liu Jun Lv Zhixiang Zheng Yucheng Wu 《Journal of Solid State Electrochemistry》2014,18(1):163-171
A GOx/Ag/TiO2 glucose biosensor was achieved by photoreducing Ag nanoparticles on TiO2 nanotube arrays (NTAs) following with adsorption of GOx. The morphology, structure, and element component of Ag/TiO2 NTAs were characterized by scanning electron microscope, transmission electron microscope, and X-ray diffraction. Ag nanoparticles were uniformly deposited on surface of TiO2 NTAs with average size of 15 nm and the size and distribution changed with the immersing time of TiO2 NTAs in AgNO3 aqueous solution. Electrochemical properties of Ag/TiO2 NTAs were characterized by cyclic voltammetry and amperometric detection of H2O2, revealing that TiO2 NTAs with immersing time of 30 min achieve the best electrochemical activity. The GOx/Ag/TiO2 NTAs biosensor with optimum conditions achieves a sensitivity of 0.39μA mM?1 cm?2 with liner range from 0.1 to 4 mM. 相似文献
922.
Yaokang Lv Dr. Jun Cheng Dr. Alexander Steiner Prof. Lihua Gan Prof. Dominic S. Wright 《Angewandte Chemie (International ed. in English)》2014,53(7):1934-1938
Metal‐doped polyoxotitanium cages are a developing class of inorganic compounds which can be regarded as nano‐ and sub‐nano sized molecular relatives of metal‐doped titania nanoparticles. These species can serve as models for the ways in which dopant metal ions can be incorporated into metal‐doped titania (TiO2), a technologically important class of photocatalytic materials with broad applications in devices and pollution control. In this study a series of cobalt(II)‐containing cages in the size range ca. 0.7–1.3 nm have been synthesized and structurally characterized, allowing a coherent study of the factors affecting the band gaps in well‐defined metal‐doped model systems. Band structure calculations are consistent with experimental UV/Vis measurements of the TixOy absorption edges in these species and reveal that molecular dipole moment can have a profound effect on the band gap. The observation of a dipole‐induced band‐gap decrease mechanism provides a potentially general design strategy for the formation of low band‐gap inorganic cages. 相似文献
923.
Wenrui Chen Ziyu Lv Peng Xiong Prof. Dr. Taolei Sun 《Angewandte Chemie (International ed. in English)》2014,53(8):2124-2129
For chiral gels and related applications, one of the critical issues is how to modulate the stereoselective interaction between the gel and the chiral guest precisely, as well as how to translate this information into the macroscopic properties of materials. Herein, we report that this process can also be modulated by nonchiral solvents, which can induce a chiral‐interaction reversion for organogel formation. This process could be observed through the clear difference in gelation speed and the morphology of the resulting self‐assembly. This chiral effect was successfully applied in the selective separation of quinine enantiomers and imparts “smart” merits to the gel materials. 相似文献
924.
Total Synthesis of (±)‐Clavilactones A,B, and Proposed D through Iron‐Catalyzed Carbonylation–Peroxidation of Olefin 下载免费PDF全文
Leiyang Lv Prof. Dr. Baojian Shen Prof. Dr. Zhiping Li 《Angewandte Chemie (International ed. in English)》2014,53(16):4164-4167
Biologically significant clavilactones A, B, and the previously proposed D have been synthesized through iron‐catalyzed carbonylation–peroxidation of a 1,5‐diene. Three steps from aldehydes, alkenes, and tert‐butylhydroperoxide build up α,β‐epoxy‐γ‐butyrolactone skeleton as a key building block for synthesis of clavilactone family and its derivatives. Based on our results, the structure of the proposed clavilactone D is not correct and requires revision. 相似文献
925.
Dr. Weiqiang Lv Dr. Xuemei Yang Dr. Wei Wang Yinghua Niu Dr. Zhongping Liu Prof. Weidong He 《Chemphyschem》2014,15(13):2688-2691
In the field of oriented‐attachment crystal growth, one‐dimensional nanocrystals are frequently employed as building blocks to synthesize two‐dimensional or large‐aspect‐ratio one‐dimensional nanocrystals. Despite recent extensive experimental advances, the underlying inter‐particle interaction in the synthesis still remains elusive. In this report, using Ag as a platform, we investigate the van der Waals interactions associated with the side‐by‐side and end‐to‐end assemblies of one‐dimensional nanorods. The size, aspect ratio, and inter‐particle separation of the Ag precursor nanorods are found to have dramatically different impacts on the van der Waals interactions in the two types of assemblies. Our work facilitates the fundamental understanding of the oriented‐attachment assembling mechanism based on one‐dimensional nanocrystals. 相似文献
926.
Efficient Water Oxidation Catalyzed by Mononuclear Ruthenium(II) Complexes Incorporating Schiff Base Ligands 下载免费PDF全文
Ting‐Ting Li Prof. Dr. Yong Chen Fu‐Min Li Wei‐Liang Zhao Chuan‐Jun Wang Dr. Xiao‐Jun Lv Dr. Quan‐Qing Xu Prof. Dr. Wen‐Fu Fu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(26):8054-8061
Four new charge‐neutral ruthenium(II) complexes containing dianionic Schiff base and isoquinoline or 4‐picoline ligands were synthesized and characterized by NMR and ESI‐MS spectroscopies, elemental analysis, and X‐ray diffraction. The complexes exhibited excellent chemical water oxidation activity and high stability under acidic conditions (pH 1.0) using (NH4)2Ce(NO3)6 as a sacrificial electron acceptor. The high catalytic activities of these complexes for water oxidation were sustained for more than 10 h at low concentrations. High turnover numbers of up to 3200 were achieved. A water nucleophilic attack mechanism was proposed. A RuV?O intermediate was detected during the catalytic cycle by high‐resolution mass spectrometry. 相似文献
927.
Taming Living Carbocations in Catalytic Direct Conjugate Addition of Simple Alkenes to α,β‐Enones 下载免费PDF全文
Dr. Jian Lv Xingren Zhong Prof. Dr. Sanzhong Luo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(27):8293-8296
A Lewis acid in the presence of an anionic phosphate ligand enables the addition of alkenes to α,β‐enones. The ligand facilitates selective β‐proton elimination by suppressing competing pathways, thus leading to vinylation adducts in high yields (up to 99 %) for a broad range of substrates. 相似文献
928.
The chitosan-microparticles reinforced cellulose biocomposite sponges regenerated from ionic liquid were prepared and characterized. Fourier transform infrared (FTIR) spectroscopy confirmed that the cellulose dissolved in 1-allyl-3-methylimidazolium chloride without derivatization. Chitosan particles as reinforcement were incorporated into the cellulose matrix. FTIR spectra indicated hydrogen bonding between hydroxyl groups of cellulose and chitosan. The biocomposite sponges showed uniform three-dimensional interconnected porous structures. The breaking strength of the sponges increased significantly, from 0.09 to 0.32 MPa with the addition of 1.0 wt% chitosan. The sponges also demonstrated excellent antibacterial activity against S. aureus and E. coli with the average inhibition zone diameters >2 mm and the inhibition rate higher than 80 %. Furthermore, the biocomposite sponges exhibited good moisture penetrability and high porosity. The water uptake ability of the sponge was >25 times of its weight in water with a fast swelling. The chitosan/cellulose composite sponge is expected to be a promising material for potential applications as wound dressing. 相似文献
929.
Determination of bisphenol A, 4‐octylphenol,and 4‐nonylphenol in soft drinks and dairy products by ultrasound‐assisted dispersive liquid–liquid microextraction combined with derivatization and high‐performance liquid chromatography with fluorescence detection 下载免费PDF全文
Tao Lv Xian‐En Zhao Shuyun Zhu Fei Qu Cuihua Song Jinmao You Yourui Suo 《Journal of separation science》2014,37(19):2757-2763
A novel hyphenated method based on ultrasound‐assisted dispersive liquid–liquid microextraction coupled to precolumn derivatization has been established for the simultaneous determination of bisphenol A, 4‐octylphenol, and 4‐nonylphenol by high‐performance liquid chromatography with fluorescence detection. Different parameters that influence microextraction and derivatization have been optimized. The quantitative linear range of analytes is 5.0–400.0 ng/L, and the correlation coefficients are more than 0.9998. Limits of detection for soft drinks and dairy products have been obtained in the range of 0.5–1.2 ng/kg and 0.01–0.04 μg/kg, respectively. Relative standard deviations of intra‐ and inter‐day precision for retention time and peak area are in the range of 0.47–2.31 and 2.76–8.79%, respectively. Accuracy is satisfactory in the range of 81.5–118.7%. Relative standard deviations of repeatability are in the range of 0.35–1.43 and 2.36–4.75% for retention time and peak area, respectively. Enrichment factors for bisphenol A, 4‐octylphenol, and 4‐nonylphenol are 170.5, 240.3, and 283.2, respectively. The results of recovery and matrix effect are in the range of 82.7–114.9 and 92.0–109.0%, respectively. The proposed method has been applied to the determination of bisphenol A, 4‐octylphenol, and 4‐nonylphenol in soft drinks and dairy products with much higher sensitivity than many other methods. 相似文献
930.
PAN BingCai WAN ShunLi ZHANG ShuJuan GUO QingWei XU ZhengCheng LV Lu ZHANG WeiMing 《中国科学:化学(英文版)》2014,57(5):763-771
Tl(I)in water even at a trace level is fatal to human beings and the ecosystem.Here we fabricated a new polymer-supported nanocomposite(HMO-001)for efficient Tl(I)removal by encapsulating nanosized hydrous manganese dioxide(HMO)within a polystyrene cation exchanger(D-001).The resultant HMO-001 exhibited more preferable removal of Tl(I)than D-001 and IRC-748,an iminodiacetic chelating polymer,particularly in the presence of competing Ca(II)ions at greater levels in solution.Such preference was ascribed to the Donnan membrane effect caused by D-001 as well as the specific interaction between Tl(I)and HMO.The adsorbed Tl(I)was partially oxidized into insoluble Tl(III)by HMO at acidic pH,while negligible oxidation was observed at circumneutral pH.The exhausted HMO-001 was amenable to efficient regeneration by binary NaOH-NaClO solution for at least 10-cycle batch runs without any significant capacity loss.Fixed-bed column test of Tl(I)-contained industrial effluent and natural water further validated that Tl(I)retention on HMO-001 resulted in a conspicuous concentration drop from 1.3 mg/L to a value lower than 0.14 mg/L(maximum concentration level for industrial effluent regulated by US EPA)and from 1–4?g/L to a value lower than 0.1?g/L(drinking water standard regulated by China Health Ministry),respectively. 相似文献