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981.
Yuanqing Zhou Jing Cao Jia Zhao Yixi Xie Junjie Fei Yuanli Cai 《Mikrochimica acta》2016,183(9):2501-2508
A temperature-responsive biosensing film consisting of the temperature-responsive block co-polymer poly (N-isopropylacrylamide)-b-poly(2-acrylamidoethyl benzoate) (referred to as PNIPAM-b-PAAE), graphene oxide (GO), and hemoglobin (Hb) was fabricated and used to modify a glassy carbon electrode (GCE). The film provides a favorable micro-environment for Hb to facilitate the electron transfer to the GCE. Hb at PNIPAM-b-PAAE/GO/Hb (PGH) film exhibits a couple of well-defined redox peaks with a formal potential of ?0.371 V (vs. SCE) and displays intrinsic electro-catalytic activity toward H2O2. The sensing film also shows temperature-tunable catalytic activity toward H2O2 that can be stimulated by temperature. Large peak currents can be seen in amperometry at 0.4 V (vs. SCE) in pH 7.0 phosphate buffer only if the temperature is above the lower critical solution temperature (LCST) of 32 °C. The response of the modified GCE is linear in the 0.1 to 3.7 μmol L?1 concentration range if operated at above 32 °C, but in the 0.2 to 3.7 μmol L?1 concentration range at below 30 °C. This behavior is attributed to the temperature-dependent phase transition of PNIPAM-b-PAAE and cooperative effect of GO. The strategy presented here in our perception meets the requirements of switchable sensors for use in bioscience and biotechnology. 相似文献
982.
Compression, tensile and mixed compression/shear tests were performed on PA66 by using a universal material testing machine in order to identify the experimental yield loci of PA66. For the mixed compression/shear tests, instead of using a complex loading device, SCS (shear-compression specimens) were used to generate the additional shear stresses. Then, the mechanical behavior of materials under complex stress states can be obtained for further analysis. Results show that the experimental yield loci of PA66 obtained by the test method proposed in the present paper agree well with the theoretical model based on three stresses invariant, which indicates the reliability of the test method. 相似文献
983.
Defect‐Controlled Preparation of UiO‐66 Metal–Organic Framework Thin Films with Molecular Sieving Capability 下载免费PDF全文
Caiqin Zhang Yajing Zhao Yali Li Prof. Xuetong Zhang Prof. Lifeng Chi Prof. Guang Lu 《化学:亚洲杂志》2016,11(2):207-210
Metal–organic framework (MOF) UiO‐66 thin films are solvothermally grown on conducting substrates. The as‐synthesized MOF thin films are subsequently dried by a supercritical process or treated with polydimethylsiloxane (PDMS). The obtained UiO‐66 thin films show excellent molecular sieving capability as confirmed by the electrochemical studies for redox‐active species with different sizes. 相似文献
984.
985.
CdSe/CdS quantum dots(QDs) functionalized by thiourea(TU) were synthesized and used as a fluorescent sensor for mercury ion detection.The TU-functionalized QDs were prepared by bonding TU via electrostatic interaction to the core/shell CdSe/CdS QDs after capping with thioglycolic acid(TGA).It was observed that the fluorescence of the functionalized QDs was quenched upon the addition of Hg~(2+).The quantitative detection of Hg~(2+) with this fluorescent sensor could be conducted based on the linear relationship between the extent of quenching and the concentration of Hg~(2+) added in the range of1-300 μg L~(-1).A detection limit of 0.56 μg L~(-1) was achieved.The sensor showed superior selectivity for Hg~(2+) and was successfully applied to the determination of mercury in environmental samples with satisfactory results. 相似文献
986.
Cong Wang Zhihua Guo Li Zhang Na Zhang Keying Zhang Bailu Fei Hongyan Wang Jigui Xu Hongwei Shi Miao Qin Lei Ren Xingxing Wu 《中国化学》2016,34(11):1151-1157
Ultralow Pt‐loading Au nanoparticles have been fabricated on the surface of reduced graphene oxide (RGO) by using underpotential deposition (UPD) monolayer redox replacement process. The Pt/Au/RGO modified electrode exhibits an excellent electrocatalytic activity toward catechol and hydroquinone. Under the optimized condition, the separation of peak‐to‐peak between hydroquinone and catechol is 197 mV, which is wide enough to distinguish the isomers of benzenediol. Catechol is detected by the Pt/Au/RGO/GCE with a low detection limit in the presence of hydroquinone. 相似文献
987.
Xiaoqing Liang Xue Wu Xiaoming Huang Yan Su Jun Hu Jijun Zhao 《Journal of Cluster Science》2016,27(3):935-946
We employ a noncollinear implementation of density functional theory (DFT) including spin–orbit coupling (SOC) interaction to calculate the magnetic properties of Irn (n = 2–5) clusters. The impact of the magnetic anisotropy on the geometric structures and magnetic properties has been analyzed. SOC leads to formation of large orbital moment and a mixing of different spin states, but does not affect the relative stability of different structural isomers for a given cluster. In order to measure the SOC effect, we further define the spin–orbit energy (Eso) and compute the exact values. Magnetic anisotropy energies (MAEs) obtained from DFT calculations are further supported by the results of torque approach. We find that MAEs of Ir2 and Ir3 in ground state configurations are 40.6 and 28.5 meV respectively, while the MAE decreases to 9 meV for Ir4. For Ir5, MAE for its ground state structure increases to 38.3 meV. 相似文献
988.
Combination of a Cyano Migration Strategy and Alkene Difunctionalization: The Elusive Selective Azidocyanation of Unactivated Olefins 下载免费PDF全文
Zhen Wu Dr. Rongguo Ren Prof. Dr. Chen Zhu 《Angewandte Chemie (International ed. in English)》2016,55(36):10821-10824
A conceptually new, efficient, and metal‐free approach for the challenging azidocyanation of unactivated alkenes is presented. The strategy of intramolecular distal cyano migration is combined with alkene difunctionalization for the first time. A variety of useful azido‐substituted alkyl nitriles are prepared in good yields and, most importantly, with exquisite regio‐ and stereo‐selectivities. 相似文献
989.
Organic‐Base‐Driven Intercalation and Delamination for the Production of Functionalized Titanium Carbide Nanosheets with Superior Photothermal Therapeutic Performance 下载免费PDF全文
Dujuan Liang Liang Cheng Xiaojing Yang Zhuang Liu Renzhi Ma Takayoshi Sasaki Fengxia Geng 《Angewandte Chemie (International ed. in English)》2016,55(47):14569-14574
The delamination of titanium carbide sheets, an intriguing class of two‐dimensional materials, has been critically dependent on the extraction of interlayer Al in acidic media, such as concentrated hydrofluoric acid (HF) or a mixture of hydrochloric acid (HCl) and a fluoride salt. Herein, we report an organic‐base‐driven intercalation and delamination of titanium carbide that takes advantage of the amphoteric nature of interlayer Al. The resulting aluminum‐oxoanion‐functionalized titanium carbide sheets manifested unusually strong optical absorption in the near‐infrared (NIR) region with a mass extinction coefficient as high as 29.1 L g?1 cm?1 at 808 nm. Thus, the performance of this material is comparable or even superior to that of state‐of‐the‐art photoabsorption materials, including gold‐based nanostructures, carbon‐based materials, and transition‐metal dichalcogenides. Preliminary studies show that the titanium carbide sheets serve as efficient photothermal agents against tumor cells. 相似文献
990.
Ruifang Gao Xiao Chen Chuntao Chen Rui Shi Fuzhong Ouyang Jiazhi Yang Dongping Sun Jian Liu 《Cellulose (London, England)》2016,23(4):2475-2485
Along with advances in life science and clinical research, there has been an increasing interest in enrichment technologies for proteins with post-translational modifications. Here we report a new platform to enrich and detect phosphopeptides using the hybrid nanofibers synthesized from bacterial cellulose (BC). Hydrothermal reactions have successfully been employed to synthesize BC@mTiO2 hybrid nanofibers. The morphology of the hybrid nanofibers has been characterized in detail. They are featured with tremendously increased specific surface areas and appropriate pore size for adsorption of phosphopeptides with high efficiency. The BC@mTiO2 tips allow improving both the sensitivity and selectivity of mass spectrometry by nearly two orders of magnitude compared with the commercial tips. As a robust and highly cost-effective platform, our approach has provided a nanotechnology invention to enrich and detect phosphorylated proteins with important biomedical applications. 相似文献