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81.
太阳红外光谱中蕴含着丰富的物理信息,其中CO 4.6μm波段是具有代表性的分子谱带,其形成于温度极小区附近,对研究太阳物理具有极其重要的意义。为获得CO 4.6μm波段太阳单色像,本文建立了一套全反射太阳红外成像观测系统。该系统采用定天镜跟踪引光,通过成像反射镜将太阳成像于3~5μm波段红外相机的焦平面上,该相机采用的是国产HgCdTe焦平面阵列器件。同时,为提高信噪比,提出了一种有效计算平场提取观测目标的方法,并利用该方法获得了CO 4.6μm波段的太阳单色像。 相似文献
82.
Da Xu Zhong Lan Gao Na Li Ke An Li Key Laboratory of Bioorganic Chemistry Molecular Engineering of Ministry of Education College of Chemistry Molecular Engineering Peking University Beijing China 《中国化学快报》2007,18(5):561-564
Ru(bpy)_(3~(2 )) electrochemiluminescence (ECL) was applied to determination of rutin. ECL intensity of Ru(bpy)_(3~(2 ))could be enhanced in the presence of rutin in basic solution on platinum electrode. At pH 9.9, light emission intensity was found to be linear with rutin in the range of 1-50 mmol/L. 相似文献
83.
Rabindra N. Roy Lakshmi N. Roy Jason G. Grant Mason P. Cummins Bennett J. Tabor III Sarah J. Richards Curtis A. Himes Bret R. Lively Penny L. Blackwell Ashley N. Simon 《Journal of solution chemistry》2002,31(11):861-872
The values of the second dissociation constant, pK
2, for the dissociation of the NH+ charge center of the zwitterionic buffer compounds 4-(N-morpholino)butanesulfonic acid (MOBS), and N-(2-hydroxyethyl)piperazine-N-4-butanesulfonic acid (HEPBS) have been determined from 5 to 55°C, including, 37°C at intervals of 5°C. The electromotive-force (emf) measurements have been made utilizing hydrogen electrodes and silver–silver chloride electrodes. The value of pK
2 for MOBS was found to be 7.702 ± 0.0005, and 8.284 ± 0.0004 for HEPBS, at 25°C, respectively. The related thermodynamic quantities, G
o, H
o, S
o, and C
p
o for the dissociation processes of MOBS and HEPBS have been derived from the temperature coefficients of pK
2. Both the MOBS and HEPBS buffer materials are useful as primary pH standards for the control of pH 7.3 to 8.6 in the region close to that of physiological fluids. 相似文献
84.
H. Fiedler 《Numerische Mathematik》1987,51(5):571-581
Summary Interpolatory quadrature formulae consist in replacing
by
wherep
f
denotes the interpolating polynomial off with respect to a certain knot setX. The remainder
may in many cases be written as
wherem=n resp. (n+1) forn even and odd, respectively. We determine the asymptotic behaviour of the Peano kernelP
X
(t) forn for the quadrature formulae of Filippi, Polya and Clenshaw-Curtis. 相似文献
85.
B. Misra 《Journal of statistical physics》1987,48(5-6):1295-1320
It is widely recognized that for highly unstable dynamical systems there exists a fundamental limitation on predictability and determinism. An important class of such highly unstable systems is the class of K-flow, which is further characterized by the existence of time-asymmetric objects in the form of K-partition. Our recent approach to the problem of irreversibility has shown that when the implications of the limitation on determinism arising from strong form of instability and those of the existence of K-partition are consistently taken into account, one is naturally led from the physically unrealizable deterministic evolution of phase points to an entropy-increasing stochastic Markovian evolution. Furthermore, this transition is not the result of extraneously imposed coarse graining and/or approximation schemes, but can be brought about by an invertible transformation whose existence and construction are determined by the nature of the instability of the dynamical system itself. After a brief review of this theory which also contains some relatively new remarks, we prove that classical Klein-Gordon field (both massive and massless) possess the structure of K-flow. This seems to provide the first examples of relativistic systems that are K-flows. Some of the implications of this result are briefly discussed. From a mathematical point of view, this seems to be a first step toward an ergodic theory of partial differential equations. In the process, we also provide an independant group-theoretic proof of the existence of incoming and outgoing subspaces of the scattering theory of Lax and Phillips for the wave equation. 相似文献
86.
Composite membranes were prepared by (a) infiltrating NAFION with SiO2-P2O5-ZrO2 sol, and (b) recasting a film using NAFION solution containing SiO2-P2O5-ZrO2 sol. The membranes were characterized by Differential Thermal Analysis and ac-impedance spectroscopy as a function of relative humidity. The influences of the heat treatment (80°C–150°C) and cleaning on the electrical properties were investigated. The incorporation of SiO2-P2O5-ZrO2 gels into NAFION lead to improvements in its thermal stability and proton conductivity. 相似文献
87.
A. M. Vinogradov 《Acta Appl Math》1986,5(2):169-180
First we propose a model of visual perception essentially based on the Keldysh-Chernavsky-Sossinsky three-channel theorem, from which three-dimensionality of space follows. Second, we associate with a system of subgroups H
1, ..., Hs of a given group G a geometric object, called a group crystal, in order to visualize G. How this notion works is illustrated via the Burnside problem. 相似文献
88.
Kenzo Sato 《International Journal of Infrared and Millimeter Waves》1986,7(6):927-947
Under the influence of perpendicularly applied positive electro-static field less than 103V/cm to silk fibron textiles, at the high frequency side of the C2–O bending reflection band (450350 cm–1), effect of step creation and step annihilation of the C2–O pseudo dending bands was induced in three stages at 600450 cm–1 region IR spectroscopically relating to the stepnized statistical transfer of the unbonded 2P2, electrons in carbon which present with density of 4.0×1014/cm2 in the surface mono-layer of silk fibroin from the states formed in (–C1–C2–N–)m spiral chains upto the pseudo-bending states formed in C2–O bondings. Fine 90 steps measured overlapping on these four types of C2–O reflection bands were analysed as to consist four step series and they were shown as,y = A·Jm + B cm–1 with A=20, B=521, m=0.55 and J=1, 2...18 for the B-series.And with A=39, B=283, m=0.63 and J=1, 2 ...17 for the C-series.y
J = A·J + B cm–1 with A=11.42, B=201 and J=1, 2...13, for the D-series. And, stepnized C2–O bending bands including that of permanent oscillators and pseudo-bending oscillators induced by the effect of transfer of the unbonded 2P2 electrons in carbon atoms were shown as, EN=A·N2+B·N+C (eV) with A=–1.50×10–3, B=1.65×10–2 and C=2.4×10–2. 相似文献
89.
ab initio Calculation of the Cl2C=CHOMe molecule has been carried out with geometrical optimization in the split valence basis set in the RHF/6-31G*//RHF/6-31G* approximation. An analysis of the populations of the p-orbitals of the Cl atoms implies the absence of p,-conjugation between the unshared electron pairs of these atoms and the -bond. The asymmetry parameters of the electric field gradient at the35Cl nuclei, calculated from the 3p-orbital populations of the Cl atoms, practically coincide with the experimental values.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2369–2372, December, 1995.The authors are grateful to G. S. Beloglazov for assistance in accomplishingab initio calculations. 相似文献
90.
Itsuo Furuoya 《Catalysis Surveys from Japan》1999,3(1):71-73
The vapor phase catalytic reaction between aromatic carboxylic acid and acetic acid was investigated. Many metal oxides catalyzed the reaction between 2methylbenzoic acid (OTA) and acetic acid (AA) to produce 2methylacetophenone (OMA), and weakly acidic oxides such as Th, U, Ce, and La oxide exhibited higher yield of OMA. The OMA yield depended on the catalyst support. SiO2, Al2O3, TiO2, and ZrO2 with a surface area of less than 200 m2 g–1 appeared to be suitable as industrial catalyst supports. CeO2 on Al2O3was chosen as an industrial catalyst for the synthesis of OMA because of higher productivity, longer catalyst life, and lifting of legal restrictions on catalyst handling. This catalyst system can also be applied to the syntheses of acetophenone, nitroacetophenone, and chloroacetophenone. 相似文献