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981.
Yuling Chen Chao Chen Ruitao Lv Wanci Shen Feiyu Kang Nyanhwa Tai Zhenghong Huang 《中国化学快报》2018,29(4):616-619
By controlling the electroplating time of solution containing Mn(Ac)2, the MnO2 nanosheets were self-assembled to the honeycomb structure and showed an excellent electrochemical performance in 1 mol/L Na2SO4 electrolyte. Via pairing with activated carbon as negative electrode, the capacitor could deliver a maximum energy density of 43.84 Wh/kg and a maximum power density of 6.62 kW/kg. 相似文献
982.
983.
Thermodynamic modeling of fluids (liquids and gases) uses mostly series expansions which diverge at low temperatures and do not fit to the behavior of metastable quenched fluids (amorphous, glass like solids). These divergences are removed in the present approach by the use of reasonable forms for the “cold” potential energy and for the thermal pressure of the fluid system. Both terms are related to the potential energy and to the thermal pressure of the crystalline phase in a coherent way, which leads to simpler and non diverging series expansions for the thermal pressure and thermal energy of the fluid system. Data for solid and fluid argon are used to illustrate the potential of the present approach. 相似文献
984.
MOVPE growth of grade-strained bulk InGaAs/InP for broad-band optoelectronic device applications 总被引:1,自引:0,他引:1
Shurong Wang Wei Wang Hongliang Zhu Lingjuan Zhao Ruiyin Zhang Fan Zhou Huiyin Shu Rufeng Wang 《Journal of Crystal Growth》2004,260(3-4):464-468
In this paper we present a novel growth of grade-strained bulk InGaAs/InP by linearly changing group-III TMGa source flow during low-pressure metalorganic vapor-phase epitaxy (LP-MOVPE).The high-resolution X-ray diffraction (HRXRD) measurements showed that much different strain was simultaneously introduced into the fabricated bulk InGaAs/InP by utilizing this novel growth method. We experimentally demonstrated the utility and simplicity of the growth method by fabricating common laser diodes. As a first step, under the injection current of 100 mA, a more flat gain curve which has a spectral full-width at half-maximum (FWHM) of about 120 nm was achieved by using the presented growth technique. Our experimental results show that the simple and new growth method is very suitable for fabricating broad-band semiconductor optoelectronic devices. 相似文献
985.
Quality evaluation of Yin Chen Hao Tang extract based on fingerprint chromatogram and simultaneous determination of five bioactive constituents 总被引:2,自引:0,他引:2
Wang X Lv H Sun H Jiang X Wu Z Sun W Wang P Liu L Bi K 《Journal of separation science》2008,31(1):9-15
A completely validated method based on HPLC coupled with photodiode array detector (HPLC-UV) was described for evaluating and controlling quality of Yin Chen Hao Tang extract (YCHTE). First, HPLC-UV fingerprint chromatogram of YCHTE was established for preliminarily elucidating amount and chromatographic trajectory of chemical constituents in YCHTE. Second, for the first time, five mainly bioactive constituents in YCHTE were simultaneously determined based on fingerprint chromatogram for furthermore controlling the quality of YCHTE quantitatively. The developed method was applied to analyze 12 batches of YCHTE samples which consisted of herbal drugs from different places of production, showed acceptable linearity, intraday (RSD <5%), interday precision (RSD <4.80%), and accuracy (RSD <2.80%). As a result, fingerprint chromatogram determined 15 representative general fingerprint peaks, and the fingerprint chromatogram resemblances are all better than 0.9996. The contents of five analytes in different batches of YCHTE samples do not indicate significant difference. So, it is concluded that the developed HPLC-UV method is a more fully validated and complete method for evaluating and controlling the quality of YCHTE. 相似文献
986.
Preparative parallel high performance liquid chromatography combined with solvent partition and other pretreatments were adopted to separate and purify compounds from an extract of Scutellaria barbata D. Don. Mass-triggered fraction collection allowed the rapid and precise isolation of target compounds. Twelve compounds were isolated from the extract of S. barbata D. Don, their purity in area percent was determined by HPLC analysis, and the structures of seven compounds were further identified with HPLC/ESI-MS, (1)H NMR, and( 13)C NMR, among which 4-(3,4-dihydroxy-phenyl)-but-3-en-2-one, acacetin-7-diglucuronide, and luteolin-7-diglucuronide were the first to be identified from this plant. The results demonstrated that multi-channel parallel preparative HPLC/UV/MS is an efficient method for isolation and purification of compounds from natural products. 相似文献
987.
988.
989.
Single crystals of new Cu,Lu(Ho)–alumoborate and known Cu,Al–borate were synthesized through reaction between CuB2O4 and LnBO3 on the Al2O3 surface by annealing at 1100 °C. Structure of commensurate modification of Ln4AlCu2B9O23, (Ln = Lu,Ho), sp. gr. , was solved at room temperature. It was found that a low–temperature (110 K) modification possesses incommensurate modulations with modulation vector q =(0, 0, 0.132). The nonaborate block – [B9O23]19– – 9[6T+3Δ] forms an isolated unique dense closed anionic unit. This block is terminated by Al–tetrahedrons in the chessboard pattern, resulting in formation of complex alumoborate layer [AlB9O23]16–. Apical oxygen of central BO3 triangle of the nonaborate block seems to be the source of modulations observed in low temperature polymorph. Cationic layers with the Ln and Cu atoms are alternating along c axis with anionic layers. The structure Cu2Al6B4O17, previously studied by the Rietveld method, was corroborated by single crystal data and was compared with LiAl7B4O17. 相似文献
990.