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991.
On Neumann-Bessel series 总被引:2,自引:0,他引:2
In this paper, we shall introduce a kind of biorthogonal series: Neu mann-Bessel series, then give an expression of kernel
functions, an equiconvergence theorem, and finally discuss its application in Bessel series. 相似文献
992.
The collision-induced absorption of the symmetric vibration of CO2 has been observed in the pure gas at densities from 20.0 to 40.0 amagat and at temperatures of 273, 298, and 323 K using infrared techniques. From the integrated intensities of the bands and using the (exp ?4) model of van Kranendonk, it is possible to deduce a value for the first derivative of the quadrupole moment with respect to the vibrational coordinate. For CO2 the contribution from quadrupole distortion to the binary absorption coefficient is reported for several temperatures. The (exp ?4) model of van Kranendonk is used to calculate the binary absorption coefficients for the fundamental vibrational bands of N2 and O2 at temperatures from 70 to 340 K. The parameters λ and p/σ describing the magnitude and range of the short-range collision-induced dipole moments were determined using the known experimental absorption coefficients. The contributions from atomic distortion and quadrupole distortion to the binary absorption coefficient are calculated for N2 and O2. 相似文献
993.
994.
本文用X射线衍射分析方法,研究铝铬红颜料的相组成和合成条件关系,发现按NazCrO, " 2HZ0 : NazMoOa : Pb(NO,)z=85 : 15 : 110mo1原料比,用共沉淀方法合成的颜料均由黄色铬酸铅和红色铝铬酸铅固溶体组成.二者比例受合成条件变化而有很大差别。指标化结果表明:红色相钥铬酸铅固溶体属单斜晶系,空间群C.'z/c.a:7. 250(8) } ,6:12. d4d ( 7 )人,c:5.119(5)人,夕=132. 58 (6 )0,化学式Pb (Cro. eeMoo. }z )U:每个单胞由四个分子组成所得粉末衍射的数据可以代替)CPDS19-685号卡片.可以用定量PbCrO,相含量的方法来表征颜料的质量。 相似文献
995.
根据结构分支型初始后屈曲中有约束的有限元平衡方程组的特点,推导了一种具有工程实用价值的变换方法,将其化为无约束的线性方程组,并给出了数值算例。 相似文献
996.
本文介绍了用γ共振吸收法测量40Ca 9603.9keV,10321.0keV两组能级和9864.6,9868.8keV一组双重态能级的能级宽度,选用39K(p,γ)反应所放出的γ射线激发相应的40Ca吸收核能级。对于9603.9keV,10321.0keV的能级宽度,这里给出了比较精确的结果,相应的能级宽度分别为Γ=188±47eV,Γ=91±15eV。对于9864.6,9868.8keV能级,结果为Γ=100±24eV,Γ=899±214eV,由于40Ca 9864.6,9868.8keV两能级靠得很近,因此这里用γ共振吸收法测量它们的能级宽度与以往有所不同,将同时有两组γ射线用来激发同样两个能级而发生交叉激发。我们对相应的实验处理方法作了推广。此外,用(p,γ)共振产额法测量了40Ca 9603.9keV,10321.0keV能级宽度,得到了与γ共振吸收法一致的结果。本文还对40Ca 9603.9keV,10321.0keV能级的(p,γ)共振强度Spγ、同位旋T等进行了讨论。
关键词: 相似文献
997.
Sang Il Jeon Mu Shik Jhon 《Journal of polymer science. Part A, Polymer chemistry》1984,22(11):3555-3561
Isotactic and syndiotactic poly(2-hydroxyethyl methacrylate) (PHEMA) have been prepared. Intrinsic viscosity–molecular weight relationships were established for the isotactic and syndiotactic PHEMA in N,N-dimethylformamide (DMF) at 25°C by solution viscometry and light scattering. The unperturbed dimensions and interaction parameters were examined in DMF, water, methanol, ethanol, and water–methanol (1:7 by volume) mixture for isotactic PHEMA and in DMF, methanol, and water–methanol (1:7 by volume) mixture for syndiotactic PHEMA using the Stockmayer–Fixman representation. The results suggest that the compact random coil structure for isotactic PHEMA occurs in water solvent and the isotactic PHEMA is more highly extended in polar solvents. 相似文献
998.
Elisa Lozano-Chaves Maria -Purificación Hernández-Artiga Antonio Muñoz-Leyva 《Mikrochimica acta》1994,116(1-3):91-99
A new spectrophotometric method for the determination of phosphate in urine is proposed, based on the ligand exchange extraction produced by phosphate solution at pH 7.5 when it is shaken with a solution of Fe(III) indole-2-carboxylate iniso-amyl alcohol. The organic layer decoloration is measured at 400 nm and the phosphate indirectly determined. The sensitivity of the method is 1.07 × 103 1 mol–1 cm–1, the linear working range 1–15 × 10–5 mol/l of phosphate and the relative standard deviation 5%. It does not require previous treatment of the sample and it is free from interferences by other normal or pathological constituents of the urine samples. The results agreed closely with those obtained by using a Sigma Diagnostics procedure for inorganic phosphorus, based on the Fiske-SubbaRow method. The method does not require special instrumentation and is not expensive. 相似文献
999.
The defects associated with interstitial oxygen in lead tungstate crystals (PbWO4) are investigated by the relativistic self-consistent discrete variational embedded cluster method. The research work is focused on the density of states of interstitial oxygen defects and relational Frankel defects. The transition state method is used to calculate excitation energy of different electron orbits. Simulation results show that the existence of defects related to interstitial oxygen can diminish the bandwidth of the WO4^2- group, and it might produce the green luminescence, Frankel defects associated with interstitial oxygen could result in the absorption at 420nm. 相似文献
1000.
L. Torres M. Zazo J. Iñiguez C. de Francisco J. M. Muñoz 《Applied Physics A: Materials Science & Processing》1995,60(3):303-307
FerroMagnetic Resonance (FMR) measurements of polycrystalline nickel ferrites at 11 GHz from 77 to 400 K have been carried out. The different contributions to the FMR linewidth have been studied by a computational technique based on the parameters previously obtained for single-crystal nickel ferrite. A new qualitative comparison between the FMR and disac-commodation measurements by means of the induced anisotropy formalism is presented. 相似文献