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951.
Fu ZY Wu XT Dai JC Wu LM Cui CP Hu SM 《Chemical communications (Cambridge, England)》2001,(18):1856-1857
A hydrothermally synthesized mixed-ligand molecular solid composed of pillared bilayers has been formulated; it presents a new remarkable three-dimensional architecture sustained by the catenation of two-fold decked layers, and exhibits intense photoluminescence upon photoexcitation at 314 nm. 相似文献
952.
Electrochemical studies of the effect of lanthanide ions on the activity of glutamate dehydrogenase 总被引:6,自引:0,他引:6
Using the electrochemical method based on the "diffusion" layer concept of the convective system, the effect of lanthanide ions La3+ and Eu3+ on the activity of glutamate dehydrogenase (GLDH) has been determined. In suitable concentrations, the lanthanide ions La3+ and Eu3+ can activate the GLDH in the reductive amination of alpha-Ketoglutarate (alpha-KG). The activation mechanism would be that the lanthanide ions could interrupt the binding of NAD+ to GLDH by combining preferentially to NAD+. This mechanism was proposed by the voltammetric studies. 相似文献
953.
Abu-Zayyad T Belov K Bird DJ Boyer J Cao Z Catanese M Chen GF Clay RW Covault CE Cronin JW Dai HY Dawson BR Elbert JW Fick BE Fortson LF Fowler JW Gibbs KG Glasmacher MA Green KD Ho Y Huang A Jui CC Kidd MJ Kieda DB Knapp BC Ko S 《Physical review letters》2000,84(19):4276-4279
The average mass composition of cosmic rays with primary energies between 10(17) and 10(18) eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the muon density as a function of energy. The results show that the composition is changing from a heavy to lighter mix as the energy increases. 相似文献
954.
C.V. Subba Reddy Z.R. Deng Q.Y. Zhu Y. Dai J. Zhou W. Chen S.-I. Mho 《Applied Physics A: Materials Science & Processing》2007,89(4):995-999
Molybdenum trioxide (MoO3) and PPyxMoO3 (x=0.5 and 1) nanobelts were obtained by the simple hydrothermal process from MoO3 sol. The morphology and structure of the samples were characterized using X-ray diffractometry (XRD), Fourier transformation
infrared spectroscopy (FTIR), Raman spectra, SEM and AFM. The results show that the H atoms in polypyrrole are H-bonded with
the O atoms in the Mo=O bonds of MoO3 nanobelts. Using the electrolyte, we fabricated electrochemical cells with a configuration of Li/(LiPF6+EC+DMC)/(MoO3+acetyleneblack+PTFE) and studied discharge profiles.
PACS 81.07.BC; 81.05.Je; 82.47.Aa; 82.45.Fk; 82.45.Gj 相似文献
955.
Super-hydrophobic PTFE surfaces were obtained by irradiation of 200 keV Xe+ ion with the fluence of 6.2×1013 ions/cm2. The contact angle of water on such surface is as large as 161±3°. SEM and XPS were used to investigate how the topological and chemical changes affect the wettability of the irradiated surface. Needle like structures at nanometer scale caused by irradiation are considered to be the reason of the super-hydrophobicity. The formation of oxygen containing group and defluorination effect on the treated surface are inferred to have negative contribution to the hydrophobic optimization of PTFE surface. 相似文献
956.
We study three types of practical optimization problems faced by a firm that can control its liquid reserves by paying dividends
and by issuing new equity. In the first problem, we consider the classical dividend problem without equity issuance. The second
problem aims at maximizing the expected discounted dividend payments minus the expected discounted costs of issuing new equity
over strategies associated with positive reserves at all times. The third problem has the same objective as the second one,
but with no constraints on the reserves. Under the assumption of proportional transaction costs, we identify the value functions
and the optimal strategies. We also present the relationship between three problems. 相似文献
957.
Lü Qing WANG ShuFang LI LongJiang WANG JiangLong DAI ShouYu YU Wei FU GuangSheng 《中国科学:物理学 力学 天文学(英文版)》2014,57(9):1644-1648
High temperature electrical and thermal transport properties, that is, electrical conductivity, Seebeck coefficient and thermal conductivity, of CdO ceramics have been investigated. Because of the good electrical properties and low thermal conductivity, the dimensionless figure-of-merit ZT of the CdO ceramics reaches 0.34 at 1023 K. This value is comparable to the best reported ZT for the n-type oxide ceramic thermoelectric materials and remains as potential to be further improved by porosity controlling or nanostructuring. 相似文献
958.
引入电流负反馈会使放大电路的输出电阻变大,这种变化在实验测量时几乎没有出现。我们在分析原因后,提出了一种简单、易行的解决方案,并且对电路参数进行了合理化设计,使实验效果非常理想。 相似文献
959.
Through quantum-beat spectroscopy collision relaxation of a high vibrational level of SO2 at 44 877.52 cm(-1) is characterized. This is a first measurement of collision relaxation for a single, highly excited vibrational level. The deduced relaxation cross section of this excited level by Ar is 216 A(2), 5 times the area of the hard sphere, and by an ambient temperature SO2 molecule is 969 A(2), almost 20 times the hard sphere. These cross sections indicate that relaxation collisions of highly vibrationally excited molecules have effective distances much longer than van der Waals radii and involve mechanisms qualitatively different from lower excitations. 相似文献
960.
Plant phenolics: extraction, analysis and their antioxidant and anticancer properties 总被引:8,自引:0,他引:8
Phenolics are broadly distributed in the plant kingdom and are the most abundant secondary metabolites of plants. Plant polyphenols have drawn increasing attention due to their potent antioxidant properties and their marked effects in the prevention of various oxidative stress associated diseases such as cancer. In the last few years, the identification and development of phenolic compounds or extracts from different plants has become a major area of health- and medical-related research. This review provides an updated and comprehensive overview on phenolic extraction, purification, analysis and quantification as well as their antioxidant properties. Furthermore, the anticancer effects of phenolics in-vitro and in-vivo animal models are viewed, including recent human intervention studies. Finally, possible mechanisms of action involving antioxidant and pro-oxidant activity as well as interference with cellular functions are discussed. 相似文献