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151.
建立了矩阵函数单重积分的格点漂移技术,并阐述了其特殊的数学意义;把格点漂移技术应用于分立基量子系统中的一般转动算符矩阵的格点方法计算中,并将其结果应用于计算二维叠加态在一般转动算符作用下的几率分布演变比。 相似文献
152.
S. Abboudy A. E. Hamed M. E. Kassem L. I. Abou-El-Nasr 《Journal of Thermal Analysis and Calorimetry》1993,39(3):301-308
The influence of stoichiometric ratio on the phase transition of sodium potassium sulphate (NaxK1–x)2SO4 crystals is investigated in the temperature range 300–500 K. The stoichiometric ratiox is chosen to bex=0.2, 0.3, 0.4, 0.8 and 0.9. The study has been carried out by using differential scanning calorimetry, DSC technique. The value of the specific heat,C
p, at the transition temperature,T
c
, increases asx is increased up tox=0.4 and then decreases for higher values ofx. The change in the specific heat, C
p, is following a relation of the form C
p C
p (T–T
c
/T
c
)– with = 0.12 which is in a fair agreement with the 3d Ising model. Insertion of Cu2+ ions into the lattice of (NaxK1–x)2SO4 crystals leads to a multiple peak in the temperature dependence ofC
p. The results are discussed from thermodynamical point of view.We would like to thank Prof. E. F. El-Wahidy, Prof. of Solid State Physics and Head of Physics Department, Faculty of Science, Alexandria University, for his interest and support of this work. 相似文献
153.
154.
The selectivity of a column system, S, defined by equation 28, includes a variation coefficient (β) of plate number with capacity ratio which has a large influence on the peak capacity, as shown in Fig. 18. Some typical chromatograms are given. In order to predict S for a column system from Kovat's Index, equations 40 and 41 are given to calculate the constant of the carbon number rule for squalane at different temperatures or for different stationary phases. The specific retention value of heptane on squalane at different temperatures can be calculated from equation 42. The nonpolarity index, defined by equation 43, was used to calculate the retention value of heptane on various stationary phases. In liquid chromatography, the order of elution may be reversed by changing the composition of the eluent on the same chemically bonded silica (manufactured in China). The linear relations between the log retention values of different kinds of solutes or of a single solute on the silicas of different surface areas when using the same eluent are given. 相似文献
155.
156.
A set of seven bituminous coal chars has been characterised by IR spectroscopy (FTIR), thermogravimetry (TG) and elemental analysis. FTIR study provided suitable information to establish differences between coal samples according to their chemical compositions. The reactivity of these samples was also studied and correlated with the coal parameters of mean vitrinite reflectance, fuel ratio and H/C ratio. The data suggest that reactivity as determined can be correlated with the mean vitrinite reflectance, fuel ratio and H/C ratio (0.90). The order of reactivity of samples were; Amasra (S1) (R m= 0.65)>Azdavay (S4) (R m=0.99)»Armutcuk (S2) (R m=0.81)»Acenta (S3) (R m=0.92)>Ac2l2k (S6) (R m=1.11) Cay (S5) (R m=1.03)>Sogutozu (S7) (R m=2.14). 相似文献
157.
Summary A modified Wald statistic for testing simple hypothesis against fixed as well as local alternatives is proposed. The asymptotic
expansions of the distributions of the proposed statistic as well as the Wald and Rao statistics under both the null and alternative
hypotheses are obtained. The powers of these statistics are compared and its is shown that for special structures of parameters
some statistics have same power in the sence of order
. The results obtained are applied for testing the hypothesis about the covariance matrix of the multivariate normal distribution
and it is shown that none of the tests based on the above statistics is uniformly superior.
Research supported by the National Science Foundation Grant MCS 830149. 相似文献
158.
159.
Summary Based on a thorough knowledge of the actual system precision significance testing of the primary eigen values, resulting from principal component analysis of the two-dimensional data array of HPLC with photodiode-array detection, is a powerful means to uncover unresolved chromatographic peaks. The implementation of this chemometric technique for assuring peak homogeneity and results showing the efficiency for two-component peaks in regard to spectral characteristics, chromatographic resolution and absorbance ratio of the investigated compounds are presented. 相似文献
160.
V. Kavan Kumar R. Mahendiran P. Subramanian S. Karthikeyan A. Surendrakumar 《印度化学会志》2022,99(3):100384
One of the most significant issues of the last few decades has been tracing for renewable energy sources. Animal fleshing (ANFL) is the most common proteinaceous solid waste accured during the production of leather and it must be disposed of in an environmentally responsible manner. This paper is attempts to assess the biogas production from solid waste originating from the chrome based tannery. Anaerobic digestion of these wastes will be a viable option for waste stabilization and energy production in the form of biogas to be utilized in the industry. The bio-methane potential of the wastes were examined by mixing these wastes with various sources of inoculum and different inoculum to substrate (I/S) ratio considered. The batch experiments were carried out in 2.5 l glass reactors with a various source of inoculumviz., Cow Dung (CD), Elephant Dung (ED) and Bio-Digested Slurry (BDS) with varied inoculum to substrate (LFs) ratios for a retention time of 50 days with replications. The results obtained from the experiments showed that BDS:LF (25:75) had the highest gas production of 14505 ml (651.85 ml CH4g?1 VS) followed by CD:LF (50:50) produced 12072.5 ml (789.36 ml CH4g?1 VS) and ED:LF (75:25) produced 11252.5 ml (1492.08 ml CH4g?1 VS)with a methane content of 63.77, 61.92 and 62.72%, respectively. 相似文献