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排序方式: 共有110条查询结果,搜索用时 31 毫秒
11.
Ye E Win KY Tan HR Lin M Teng CP Mlayah A Han MY 《Journal of the American Chemical Society》2011,133(22):8506-8509
We report a facile chemical synthesis of well-defined gold nanocrosses through anisotropic growth along both <110> and <001>, whereas gold nanorods grow only along either <110> or <001>. The multiple branching was achieved by breaking the face-centered-cubic lattice symmetry of gold through copper-induced formation of single or double twins, and the resulting gold nanocrosses exhibited pronounced near-IR absorption with a great extension to the mid-IR region. As studied by discrete dipole approximation (DDA) simulations, the entire nanocross gets excited even when one of the branches is exposed to incident light. The above properties make them useful as octopus antennas for capturing near-IR light for effective photothermal destruction of cells. The cell damage process was analyzed using the Arrhenius model, and its intrinsic thermodynamic characteristics were determined quantitatively. Besides effective photothermal treatment and two-photon luminescence imaging, the near- and mid-IR-absorbing gold nanocrosses may also find applications in IR sensing, thermal imaging, telecommunications, and the like. 相似文献
12.
Gy. Szász L. Khin und Frau M. Zacskó-Szász 《Fresenius' Journal of Analytical Chemistry》1963,192(2):287-291
Zusammenfassung Es wird über eine papierchromatographische Methode zum Nachweis von Bleiverunreinigungen in Schwermetallsalzen berichtet, die auf dem Unterschied zwischen der Löslichkeit des Bleisulfats und der übrigen Schwermetallsulfate beruht. Als Lösungsmittel wird das durch Rex u. Diller vorgeschlagene Gemisch Methanol-Schwefelsäure-Wasser verwendet. Nach der Chromatographie bleibt das Blei auf der Startlinie, während die übrigen Metalle mit Rf-Werten von 0,7–0,9 wandern. In den untersuchten Co2+-, Ni2+-, Cd-, Zn- und Cu-Salzen konnten im allgemeinen Bleiverunreinigungen von 30 g/g (=0,003%) nachgewiesen werden. Ni-, Cd- und Cu-Sulfate bleiben gleichfalls auf der Startlinie zurück, weshalb in diesen Salzen das Blei nach der beschriebenen Methode nicht nachgewiesen werden kann.Herrn Prof. Dr. A. Végh sind wir für die Unterstützung unserer Arbeit zu Dank verpflichtet. 相似文献
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14.
U Myint Khin Mg Nyo Thein Thein Win 《Journal of Radioanalytical and Nuclear Chemistry》1995,201(4):263-267
60Co was used as indicator for studies on the separation of cobalt with sodium alginate. Effect of eight experimental parameters (digestion time, digestion temperature, mode of separation, concentration of reagents, pH, order of heating, ammonia, mixing of reagents) on the precipitation and separation of cobalt alginate have been investigated. 相似文献
15.
Chin KK Chuang SC Hernandez B Selke M Foote CS Garcia-Garibay MA 《The journal of physical chemistry. A》2006,110(51):13662-13666
The photophysical properties of a novel 1,2,3,4,5,6-hexasubstituted fullerene derivative (1) are examined in this study. In addition to the ground state absorption spectrum of 1, we report its triplet-triplet absorption spectrum and molar extinction coefficient (Deltae(T-T)), as well as the triplet quantum yield (PhiT), lifetime (tauT), and energy (ET). The saturation of a single six-member ring on the fullerene cage results in significant changes in the triplet state properties as compared to that of pristine C60. The triplet-triplet absorption spectrum shows a hypsochromic shift in long wavelength absorption, and both the triplet state lifetime and the triplet quantum yield are decreased. The triplet energy was found to be similar to that of C60. In addition, the quantum yield (PHI(delta)) of singlet oxygen generated by 1 was calculated and is found to be significantly less than in the case of C60. 相似文献
16.
Vasilieva T. M. Vasiliev M. N. Garaeva V. V. Zlobin I. S. Mint Zaw Ye Htau Khin Maung Kyaw Htet Wai Yan Zaw Htet Ko Ko 《Russian Physics Journal》2020,62(11):2092-2100
Russian Physics Journal - Different schemes and designs of generators of low-temperature hybrid plasma produced by simultaneous ionization of plasma-generating medium by an electron beam with... 相似文献
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The semivolatile composition of stem-bark of 10 Cinnamomum species, collected from China and Myanmar, were obtained by extraction with diethyl ether and analyzed by GC-FID and GC-MS. Identification of the substances was made by comparison of standards, mass spectra, and retention indices with literature records. Total of 74 compounds were identified. All data were statistically processed with principal component analysis and cluster analysis. Cinnamaldehyde and alpha-cubebene were found as the common constituent of the investigated population. Except Cinnamomum multiflorum, volatile terpenoids were the main constituents of all taxa. Major constituent of C. multiflorum was phenylpropanoid. Cluster subset gave the information that chemical components variation was influenced by geographical sources. Here, the first information on the semivolatile composition of six never investigated species viz. C. multiflorum, C. obtusifolium, C. inunctum, C. chartophyllum, C. pathenoxylon, and C. glanduliferum. Furthermore, those species could be alternative source of bioactive compounds. 相似文献
19.
A chemo-electro-mechanical multi-field model, termed the multi-effect-coupling pH-electric-stimuli (MECpHe) model, has been
developed to simulate the response behavior of smart hydrogels subject to pH and electric voltage coupled stimuli when the
hydrogels are immersed in a pH buffer solution subject to an externally applied electric field. The MECpHe model developed
considers multiphysics effects and formulates the fixed charge density with the coupled buffer solution pH and electric voltage
effects, expressed by a set of nonlinear partial differential governing equations. The model can be used to predict the hydrogel
displacement and the distributive profiles of the concentrations of diffusive ionic species and the electric potential and
the fixed charge density in both the hydrogels and surrounding solution. After validation of the model by comparison of current
numerical results with experiment data extracted from the literature, one-dimensional steady-state simulations were carried
out for equilibrium of the smart hydrogels subject to pH and electric coupled stimuli. The effects of several important physical
conditions, including the externally applied electric voltage, on the distributions of the concentrations of diffusive ionic
species, the electric potential, the fixed charge density, and the displacement of the hydrogel strip were studied in detail.
The effects of the ionic strength on the bending deformation of the hydrogels under the solution pH and electric voltage coupled
stimuli are also discussed. 相似文献
20.
da Silva RS Marchesi MS Khin C Lunardi CN Bendhack LM Ford PC 《The journal of physical chemistry. B》2007,111(24):6962-6968
The photochemical behavior of the tetraazamacrocyclic complex trans-RuCl([15]ane)(NO)2+ (RuNO2+) in a 10 mM phosphate buffer solution, pH 7.4, and in the presence of Ru(NH3)5pz2+ (Rupz2+) is reported. Irradiation (436 nm) of an aqueous solution containing both cationic complexes as PF6- salts labilizes NO from RuNO2+ with a quantum yield (phiNO) dependent on the concentration of Rupz2+ with a maximum value of phiNO (1.03(11)x10(-3) einstein mol-1) found for a solution with equimolar concentrations (5x10(-5) M) of the two complexes in phosphate buffer solution. The quantitative behavior of this system suggests that the two cations undergo preassociation such that photoexcitation of the visible absorbing Rupz2+ is followed by electron or energy transfer to RuNO2+, which does not absorb appreciably at the excitation wavelength, and this leads to NO release from the reduced nitrosyl complex. Notably, the NO release was not seen in the absence of phosphate buffer; thus, it appears that phosphate ions mediate NO generation, perhaps by facilitating formation of a supramolecular complex between the two ruthenium cations. Reexamination of the cyclic voltammetry of Rupz2+ showed that the electrochemical behavior of this species is also affected by the presence of the phosphate buffer. 相似文献