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91.
Jeffrey Bub 《Foundations of Physics Letters》1993,6(1):21-35
Elby (1993) has raised certain problems that appear to be devastating for modal interpretations of quantum mechanics, but do not arise for Bohm's pilot wave theory. Here I show that the features Elby identifies as objectionable in my version of the modal interpretation have their counterpart in Bohm's theory. To the extent that Bohm's theory works as a no collapse solution to the measurement problem - and I think it does - so does my modal interpretation. 相似文献
92.
S.?BabootaEmail author S.?P.?Agarwal 《Journal of inclusion phenomena and macrocyclic chemistry》2005,51(3-4):219-224
Meloxicam is a non steroidal anti inflammatory drug, used in the treatment of rheumatoid and osteoarthiritis. It is practically insoluble in water and its prolonged use is associated with the incidence of side effects like gastro intestinal perforations, ulcerations and bleeding. Therefore, an attempt has been made to improve the aqueous solubility of the drug by making an inclusion complex using hydroxy propyl β cyclodextrin(HPβ-CD). The complexes were prepared by physical mixture and freeze drying method. The different methods employed for evaluation such as DSC, XRD, SEM and FT-IR studies indicated complete formation of the complex by freeze drying method in a molar ratio of 1:2. The prepared complexes showed improved in-vitro dissolution profile as compared to the pure drug. 相似文献
93.
94.
19F and 1H NMR spectra of halocarbons 总被引:1,自引:0,他引:1
Foris A 《Magnetic resonance in chemistry : MRC》2004,42(6):534-555
19F NMR chemical shifts and coupling constants are reported for 215 compounds. For 77 of these compounds, 1H NMR spectral data are also given. Long-range couplings, including 8J(F,F) and 5J(F,H), are reported. The complexity of halocarbon spectra owing to the presence of rotational isomers, asymmetric centers, long-range couplings, and chlorine isotope effects are illustrated, and the methods used for analyzing such complex spectra are briefly discussed. 相似文献
95.
Glow discharge mass spectrometry 总被引:5,自引:0,他引:5
Hoffmann V Kasik M Robinson PK Venzago C 《Analytical and bioanalytical chemistry》2005,381(1):173-188
Over the past twenty years or so, glow discharge mass spectrometry (GDMS) has become the industry standard for the analysis of trace elements in metals and semiconductors. A review of its history is followed by a picture of the present situation and a look to where the future may lie. Applications are summarised, including the ability of GDMS to offer depth-resolved data and non-conductor analysis, and the well-documented quantitative nature of the results is reviewed. The effects resulting from the physical properties of the analyte material are discussed at length. Finally, recent work such as fast flow sources and pulsed glow discharges is reviewed. 相似文献
96.
《Surface and interface analysis : SIA》2003,35(11):932-939
Error surfaces are calculated for the fitting of concentration–depth profiles to angle‐resolved x‐ray photoelectron spectroscopy (ARXPS) data. The shapes of the error surfaces indicate that model parameters related to composition (especially at the very surface of the sample) are well constrained by the data, whereas parameters related to depth have a less significant impact on the fit. It is then shown that certain parameters in the different depth profile models employed are highly correlated and that the different models convey essentially the same information in different ways. Finally, a compromise profile definition is proposed for the fitting of constrained but flexible depth profiles to ARXPS data. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
97.
Nevin Çelebi Osamu Shirakura Yoshiharu Machida Tsuneji Nagai 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(4):407-413
Inclusion complex formation of piromidic acid (PA) with dimethyl--cyclodextrin (DM--CD) in aqueous solution and in the solid state was confirmed by the solubility method, differential scanning calorimetry (DSC) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The apparent stability constant,K
c
, of the complex was estimated to be 244 M–1. The stoichiometry of the complex was given as the ratio 1:2 of PA to DM--CD. The dissolution rate of the PA/DM--CD complex was much greater than that of intact PA.Presented at the Fourth International Symposium on Inclusion Phenomena and the Third International Symposium on Cyclodextrins, Lancaster, U.K., 20–25 July 1986. 相似文献
98.
血浆样品经0.01mol·L-1盐酸和无水乙醇浸取,在碱性条件下用氯仿萃取,GG-MS-选择离子测量法测定,外标法定量。在选定的色谱条件下,盐酸克仑特罗的检出限为0.05ng,线性范围为0.1-100ng,方法的平均回收率为95.6%,RSD小于6.82%(n=6)。该法毋需衍生化,基质无干扰,简便可靠,适用于生物材料中克仑特罗的快速分析。 相似文献
99.
100.
摘要利用改进的可视化装置, 研究了10°锥角的台锥型液相色谱柱内的谱带流型与柱参数变化的关系. 将有机玻璃柱管加工成内圆台外方型的一体结构, 选择折射率一致的色谱固定相硅胶和流动相环己烷, 使整个色谱柱成为高度清晰的透明体, 能直接观察柱中彩色样品谱带的动态三维流型. 研究结果表明, 在实验条件范围内, 流动相流速对谱带流型无影响, 填料的形状和性质对塞子状流型有一定程度的影响. 比较了柱长为5cm和等比例放大后柱长为10cm锥型柱内的流型, 发现放大后的锥型柱内仍然保持塞子状流型, 总柱效等比例增加. 表明继续按比例放大成为工业规模色谱柱后仍能保持塞子状流型. 相似文献