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111.
Somayazulu M Madduri A Goncharov AF Tschauner O McMillan PF Mao HK Hemley RJ 《Physical review letters》2001,87(13):135504
Simple molecular solids become unstable at high pressures, typically transforming to dense framework and/or metallic structures. We report formation of an unusual ionic solid NO(+)NO(3)(-) (nitrosonium nitrate) from N(2)O at pressures above 20 GPa and temperatures above 1000 K. Synchrotron x-ray diffraction indicates that the compound crystallizes with a structure related to the aragonite form of CaCO(3) and NaNO(3). Raman and infrared spectroscopic data indicate that the structure is noncentrosymmetric and exhibits a strong pressure dependent charge transfer and orientational order. 相似文献
112.
额尔齐斯河(新疆段)水质评价 总被引:2,自引:0,他引:2
对额尔齐斯河1993~1999年的水质污染数据用因子分析的方法进行分析,得到评价额尔齐斯河水质污染的有机污染因子,综合污染因子和金属污染因子,并以此对额尔齐斯河水质污染情况作出较客观的评价。 相似文献
113.
本文主要讨论s.i.s.向量随机测度关于白噪声的积分的收敛性,我们得到了如下结果设X是具type2的Banach空间,{Fn}∞n=0是一列被μ所控制的X值s.i.s随机测度,对任意的E∈∑,E[Fn(E)]=0,E‖Fn(E)‖2<+∞,{Fn(E)}∞n=0是一致W弱可积,且{Fn}∞n=1弱几乎收敛到F0,则(1)对每个n≥0∫FndW是s.i.s向量随机测度;(2)∫FndWwp→∫F0dW. 相似文献
114.
Hayward Tammy Kay Hamilton Jenny Tholudur Arun McMillan James D. 《Applied biochemistry and biotechnology》2000,84(1-9):859-874
Researchers studying cellulase enzymes for the economical production of fuel ethanol envision cellulose as the carbon source.
However, submerged Trichoderma reesei cultures grown on cellulose exhibit high run-to-run variability. Thus, an investigation of 30 batch cellulase production
experiments was instrumental in determining fermentation conditions that improved enzyme titers, yields, and productivities.
Eighteen of the 30 batch experiments experienced minimal process upsets and were classified into eight groups based on agitation
rate, gas sparge rate, and the use of oxygen supplementation. Comparing corn steep liquor with yeast extract/peptone also
tested the effect of different sources of nitrogen in the media. Average 7-d enzyme titers were doubled from 4 to 8 FPU/mL
primarily by increasing aeration. 相似文献
115.
(Molecular Physics, 1994, 83, 309–326) 相似文献
116.
Andrew J. Pugsley Andrea Sella Paul F. McMillan 《Journal of solid state chemistry》2011,184(9):2345-2352
We present results of an XAS and EXAFS study of the synthesis of Ge nanoparticles formed by a metathesis reaction between Mg2Ge and GeCl4 in diglyme (diethylene glycol dimethyl ether). The progress of the formation reaction and the products formed at various stages in the processing was characterised by TEM and optical spectroscopy as well as in situ XAS/EXAFS studies using specially designed reaction cells. 相似文献
117.
Abstract This paper is devoted to investigate extinction and nonextinction conditions of the extended Beverton–Holt equation (BHE) for dynamics of populations in Ecology when potential discontinuities at sampling points are included in the model. The proposed model is described by means of four sequences of parameters. Two of them are the intrinsic growth rate and the carrying capacity sequences which are included in the basic BHE model. The other two ones, namely, the harvesting (i.e., the hunting or fishing quota) and the internal consumption (which can include positive and negative migrations in the considered population habitat) sequences are included to parameterize the model discontinuities. Such discontinuities are related to impulses in the corresponding continuous‐time logistic equation. The obtained results establish how the harvesting quota and/or the internal consumption has to be fixed to guarantee the population nonextinction or, eventually, its extinction. Finally, some controllability results related to the search of a carrying capacity sequence such that the solution of the proposed impulsive BHE tracks a reference one are obtained. 相似文献
118.
采用水热合成法制备了CaF2:xYb3+,yEr3+(x=0.1~0.8,y=0.01~0.08)纳米颗粒,利用X射线粉末衍射仪、透射电子显微镜和F-4600荧光分光光度计表征了样品的物相和形貌尺寸,并探究了Yb3+和Er3+掺杂浓度对样品的上转换发光性质的影响。结果表明,所合成的样品为立方相,球形颗粒,平均直径为 12 nm,敏化剂Yb3+的最佳掺杂摩尔分数为20%,而激活剂Er3+的最佳掺杂摩尔分数为6%。此时,绿光与红光的强度之比最大。 相似文献
119.
Hill GL Bailey E Stennett MC Hyatt NC Maddrell EM McMillan PF Hriljac JA 《Journal of the American Chemical Society》2011,133(35):13883-13885
The simultaneous application of high pressure and high temperature has been used to achieve direct ion exchange of large cesium cations for the small sodium cations found in the zeolite natrolite by putting it into a superhydrated state with increased pore size. The larger cations remain trapped upon pressure release, and thus, this method is a means of producing new cationic forms of zeolites. 相似文献
120.