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901.
Zhou XJ Shi J Yoshida T Cuk T Yang WL Brouet V Nakamura J Mannella N Komiya S Ando Y Zhou F Ti WX Xiong JW Zhao ZX Sasagawa T Kakeshita T Eisaki H Uchida S Fujimori A Zhang Z Plummer EW Laughlin RB Hussain Z Shen ZX 《Physical review letters》2005,95(11):117001
High resolution angle-resolved photoemission spectroscopy data along the (0,0)-(pi,pi) nodal direction with significantly improved statistics reveal fine structure in the electron self-energy of the underdoped (La2-xSrx)CuO4 samples in the normal state. Fine structure at energies of (40-46) meV and (58-63) meV, and possible fine structure at energies of (23-29) meV and (75-85) meV, have been identified. These observations indicate that, in (La2-xSrx)CuO4, more than one bosonic modes are involved in the coupling with electrons. 相似文献
902.
903.
Huan Huan Zhang Ya Ting Liu Rong Wang Xiao Yan Yu Xiong Wei Qu Qing Xin Zhang 《中国化学快报》2011,22(4):485-488
A novel nanodiamond-epoxy derivative(ND-EP) was synthesized by grafting epoxy monomers onto the surface of nanodiamond(ND),and characterized by FTIR and TGA.The ratio of grafted epoxy groups was determined to be 32.5 wt% by TGA.The developed methodology provides an efficient method for the functionalization of nanodiamond material,which enables a variety of advanced engineering and biomedical applications of ND. 相似文献
904.
A novel Selectfluor-mediated copper-catalyzed highly selective benzylic C-O cyclization for the synthesis 4H-3,1-benzoxazines is reported. The predominant selectivity for a benzylic C(sp(3))-H over an aromatic C(sp(2))-H bond in N-o-tolylbenzamides is achieved. 相似文献
905.
Xiong DB Okamoto NL Waki T Zhao Y Kishida K Inui H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(9):2536-2542
Heusler phases, including the full- and half-Heusler families, represent an outstanding class of multifunctional materials on account of their great tunability in compositions, valence electron counts (VEC), and properties. Here we demonstrate a systematic design of a series of new compounds with a 2×2×2 superstructure of the half-Heusler unit cell in X-Y-Z (X=Fe, Ru, Co, Rh, Ir; Y=Zn, Mn; Z=Sn, Sb) systems. Their structures were solved by using both powder and single-crystal X-ray diffraction, and also directly observed by using high-angle annular dark-field imaging in a scanning transmission electron microscope (HAADF-STEM). The VEC values of these new compounds span a wide and continuous range comparable to those for the full- and half-Heusler families, thereby implying tunability in compositions and physical properties in the superstructure. In fact, we observed abnormal electrical properties and a ferromagnetic semiconductor-like behavior with a high and tunable Curie temperature in these superstructures. 相似文献
906.
Huaping Tan Qixin Zhou Haifeng Qi Dan Zhu Xiaoxue Ma Dangsheng Xiong 《Macromolecular bioscience》2012,12(5):621-627
A new methodology is developed to conjugate hyaluronic acid (HA) hydrogel with novel nano‐fibrous architectures via non‐covalent assembly that specifically allows for targeted adipose‐derived stem cells (ASCs) differentiation and soft tissue engineering. The assembly of non‐covalently associated hydrogel network produced via the interaction of a low molecular weight heparin (LMWH) modified HA derivative and heparin interacting protein (HIP). The multifunctional star poly(ethylene glycol) (PEG) and HIP copolymer has the capability to mediate the non‐covalent assembly of nano‐fibrous HA hydrogel networks via affinity interactions with LMWH. The effect of the HIP mediation on in vitro gelation, rheological characteristics, degradation, equilibrium swelling, adipose‐derived stem cells (ASCs) proliferation and differentiation of nano‐fibrous hydrogel is examined. The results suggest the potential utility of this unique design of the bioactive nano‐fibrous HA hydrogel in directing the differentiation of ASCs and adipogenesis in ECM‐mimetic scaffolds in vitro. These studies demonstrate that this nano‐fibrous HA hydrogel can render the formulation of a therapeutically effective platform for in vitro adipogenesis applications.
907.
Modifying the β‐diketimine ligand LH 1 (LH=[ArN?C(Me)? CH?C(Me)? NHAr], Ar=2,6‐iPr2C6H3) through replacement of the proton in 3‐position by a benzyl group (Bz) leads to the new BzLH ligand 2, which could be isolated in 77 % yield. According to 1H NMR spectroscopy, 2 is a mixture of the bis(imino) form [(ArN?C(Me)]2CH(Bz) 2a and its tautomer [ArN?C(Me)? C(Bz)?C(Me)NHAr] 2b. Nevertheless, lithiation of the mixture of 2a and 2b affords solely the N‐lithiated β‐diketiminate [ArN?C(Me)? C(Bz)?C(Me)? NLiAr], BzLLi 3. The latter reacts readily with GeCl2?dioxane to form the chlorogermylene BzLGeCl 4, which serves as a precursor for a new zwitterionic germylene by dehydrochlorination with LiN(SiMe3)2. This reaction leads to the zwitterionic germylene BzL′Ge: 5 (BzL′=ArNC(?CH2)C(Bz)?C(Me)NAr) which could be isolated in 83 % yield. The benzyl group has a distinct influence on the reactivity of zwitterionic 5 in comparison to its benzyl‐free analogue, as shown by the reaction of 5 with phenylacetylene, which yields solely the 1,4‐addition product 6, that is, the alkynyl germylene BzLGeCCPh. Compounds 2–8 have been fully characterized by multinuclear NMR spectroscopy, mass spectrometry, elemental analyses, and single‐crystal X‐ray diffraction analyses. 相似文献
908.
A novel electromagnetic induction detector with two inductors for CE was described here.The two inductors were used as signal detection and reference,respectively.The parameters affecting the detector performance(including coil turns,detection distance, excitation frequency,voltage,etc.) were optimized.Under the optimum condition,the feasibility of the detector was examined by analyzing inorganic ions.The fabricated detector showed good linear relationship between the response and the analytes concentrations,with a detection limit of 13μmol/L for Na~+(S/N = 3).A variety of advantages,such as simple construction, ease of operation,and considerably universal response,suggested this novel detector a promising application prospect in analytical area. 相似文献
909.
Simultaneous determination of 20 food additives by high performance liquid chromatography with photo-diode array detector 总被引:1,自引:0,他引:1
An efficient and accurate analytical method was developed for the simultaneous determination of 20 synthetic food additives, including three sweeteners,seven food colorants,nine synthetic preservatives and caffeine,by high performance liquid chromatography (HPLC) with photodiode array detector(PDA).This method permits the detection of food additives at very low concentrations(0.005-0.150μg/mL).The applicability was verified by the determination of food additives present in various foodstuffs. 相似文献
910.
Series of carbon nanotube supported Ru-based catalysts were prepared by impregnation method and applied successfully for complete removal of CO by CO selective methanation from H2-rich gas stream conducted in a fixed-bed quartz tubular reactor at ambient pressure.It was found that the metal promoter,reduction temperature and metal loading affected the catalytic properties significantly.The most excellent performance was presented by 30 wt% Ru-Zr/CNTs catalyst reduced at 350℃.Since it decreased CO concentration to below 10ppm from 12000ppm by CO selective methanation at the temperature range of 180-240℃,and kept CO selectivity higher than 85% at the temperature below 200℃.Characterization using XRD,TEM,H2-TPR and XPS suggests that Zr modification of Ru/CNTs results in the weakening of the interaction between Ru and CNTs,a higher Ru dispersion and the oxidization of surface Ru.Amorphous and high dispersed Ru particles with small size were obtained for 30 wt% Ru-Zr/CNTs catalyst reduced at 350℃,leading to excellent catalytic performance in CO selective methanation. 相似文献