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41.
The orientation crystallization behavior of natural rubber vulcanizates was investigated by means of a dynamic X-ray diffraction technique utilizing the half-circle sector technique. The frequency dependence of dynamic diffraction intensities from diatropic and paratropic crystal planes, (002) and (200) planes, was observed over a frequency range from 10?3 to 101 Hz as a function of temperature, degree of cross-linking, static extension ratio, and dynamic strain amplitude.

The frequency dependence of the dynamic X-ray diffraction gives two dispersion regions around 10?2 and 10?1 Hz. The phase angle between the dynamic X-ray diffraction and dynamic strain of a bulk specimen is definitely positive; i.e., the dynamic strain of the specimen is always behind the dynamic orientation crystallization.

The frequency dispersion at low frequencies, around 1WZ Hz is very obvious for the (200) crystal plane and shifts somewhat to higher frequencies under those conditions that increase the mobility of self-diffusion of rubber molecules, i.e., increase of temperature and decreases of extension ratio and degree of cross-linking. The frequency dispersion at high frequencies, around 101 Hz, is rather obvious for the (002) crystal plane and does not shift appreciably under the experimental conditions.  相似文献   
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Summary An application of the Raman microprobe according to the original concept of M. Delhaye but modified to increase its sensitivity was accomplished so successfully that a good Raman spectrum of a 1m polystyrene sphere can be obtained.Moreover, to utilize the fact that the intensity of Raman scattering from a small particle is enhanced by influence of a metal substrate to be two times stronger than on a silicon wafer surface, a sampling technique adopting Press-O-Film® has been established. This is a replicating film coated with a thin gold layer for use with the electron microscope. These means have clarified the sources of particulate contaminants, especially polymer particles in the IC process, which could not be identified by conventional methods.Nothing other than Raman microprobe analysis can easily distinguish allotropic forms of carbon from particulate contaminants.
Anwendung der Raman-Mikrosonde zur Identifizierung partikulärer Verunreinigungen bei der Produktion integrierter Schaltkreise
Zusammenfassung Die Instrumentierung für die Raman-Mikrosonde nach dem ursprünglichen Konzept von Delhaye wurde so erfolgreich verbessert, daß nunmehr ein gutes Ramanspektrum von einer 1-m-Polystyrolkugel aufgenommen werden kann. Darüberhinaus wurde zur Verstärkung der Ramanstreuung kleiner Teilchen, die von einem Metallsubstrat doppelt so stark ist wie von einer Siliziumoberfläche, eine Probenahmetechnik unter Verwendung von Press-O-Film®, einem goldbeschichteten Film für die Replikattechnik in der Elektronenmikroskopie, entwickelt. Dadurch konnten die Partikelkontaminationen bei der Herstellung integrierter Schaltkreise, die durch keine andere analytische Methode identifiziert werden konnten, als Polymerteilchen erkannt werden. Außerdem kann nur die Raman-Mikrosonde zwischen den allotropen Kohlenstofformen und Mikropartikeln unterscheiden.


Presented at the 9th International Symposium on Microchemical Techniques, Amsterdam, August 28–September 2, 1983.  相似文献   
44.
Two novel membrane-bound yellow pigments natronochrome (1) and chloronatronochrome (2) were isolated from the obligately chemolithoautotrophic sulfur-oxidizing natrono(alkali)philic bacterium Thialkalivibrio versutus strain ALJ 15. They were derivatives of fully unsaturated fatty acids with a phenyl group, and their structures were determined by spectral data.  相似文献   
45.
We have found that the initial permeability μμ of Co2ZCo2Z ferrite is improved by the substitution of Ti4+Ti4+ and Zn2+Zn2+ ions for Fe3+Fe3+ ions. The substituted sample of Ba3Co2TixZnxFe24-2xO41Ba3Co2TixZnxFe24-2xO41 with x=0.85x=0.85 has a maximum μμ of 24, which is twice as large as that of the non-substituted sample with x=0x=0. The particle size and shape are changed by the substitution. This is influential in the densification and the preferential orientation of a toroidal-shape sample, which results in the improvement of μμ.  相似文献   
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Reliability of the screened Coulomb renormalization method, which was proposed in an elegant way by Alt?CSandhas?CZankel?CZiegelmann (ASZZ), is discussed on the basis of ??two-potential theory?? for the three-body AGS equations with the Coulomb potential. In order to obtain ASZZ??s formula, we define the on-shell M?ller function, and calculate it by using the Haeringen criterion, i.e. ??the half-shell Coulomb amplitude is zero??. By these two steps, we can finally obtain the ASZZ formula for a small Coulomb phase shift. Furthermore, the reliability of the Haeringen criterion is thoroughly checked by a numerically rigorous calculation for the Coulomb LS-type equation. We find that the Haeringen criterion can be satisfied only in the higher energy region. We conclude that the ASZZ method can be verified in the case that the on-shell approximation to the M?ller function is reasonable, and the Haeringen criterion is reliable.  相似文献   
48.
A new fluorescent molecular probe, 2,2′‐(1E,1′E)‐2,2′‐(4‐(dicyanomethylene)‐4H‐pyrane‐2,6‐diyl)bis(ethene‐2,1‐diyl)bis(sodium benzenesulfonate) salt ( 1 ), possessing the cyanopyranyl moieties and two benzene sulfonic acid groups was designed and synthesized to detect proteins in solution and for high‐throughput SDS‐PAGE. Compound 1 exhibited no fluorescence in the absence of proteins; however, it exhibited strong fluorescence on the addition of bovine serum albumin as a result of intramolecular charge transfer. Compared with the conventional protocols for in‐gel protein staining, such as SYPRO Ruby and silver staining, 1 achieves higher sensitivity, even though it offers a simplified, higher throughput protocol. In fact, the total time required for protein staining was 60–90 min under optimum conditions much shorter than that required by the less‐sensitive silver staining or SYPRO Ruby staining protocols. Moreover, 1 was successfully applied to protein identification by mass spectrometry via in‐gel tryptic digestion, Western blotting, and native PAGE together with protein staining by 1 , which is a modified protocol of blue native PAGE (BN‐PAGE). Thus, 1 may facilitate high‐sensitivity protein detection, and it may be widely applicable as a convenient tool in various scientific and medical fields.  相似文献   
49.
Monatshefte für Chemie - Chemical Monthly - ?The electronic absorption and polarized absorption spectra were measured at various pH conditions for ellagic acid. Comparison of these...  相似文献   
50.
We construct an atomistic silica pore model mimicking templated mesoporous silica MCM-41, which has molecular-level surface roughness, with the aid of the electron density profile (EDP) of MCM-41 obtained from X-ray diffraction data. Then, we present the GCMC simulations of argon adsorption on our atomistic silica pore models for two different MCM-41 samples at 75, 80, and 87 K, and the results are compared with the experimental adsorption data. We demonstrate that accurate molecular modeling of the pore structure of MCM-41 by using the experimental EDP allows the prediction of experimental capillary evaporation pressures at all investigated temperatures. The experimental desorption branches of the two MCM-41 samples are in good agreement with equilibrium vapor–liquid transition pressures from the simulations, which suggests that the experimental desorption branch for the open-ended cylindrical pores is in thermodynamic equilibrium.  相似文献   
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