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111.
We have developed 32-fiber and 60-fiber super high density multi fiber connector. This 32-fiber connector can be applicable for single-mode fiber and 60-fiber connector for multi-mode fiber. We have also established PC (physical contact) connection technology by optimizing polishing condition and clamping force.  相似文献   
112.
Abstract

Crystal structure of a 1:2 complex of hexakis(3-O-acetyl-2,6-di-O-methyl)-α-cyclodextrin (ADMACD) with butylacetate was determined by the X-ray method. The space group of the crystal is P212121 with Z = 4 and D x = 1.293 g cm?3, and the cell dimensions are a = 11.087(2), b = 23.543(3), and c = 31.739(6) Å. The structure was solved by the direct method and refined to the R-value of 0.123 for all the 4993 observed reflections with 1<0. The ADMACD molecule is in a round shape with the pseudo hexagonal symmetry. Methyl and acetyl groups point towards the outside of the molecule. Because of the acetyl groups attached to O3 and methyl groups attached to O6, the intramolecular cavity is ca. 3 Å deeper than the cavity of native α-CD. One butylacetate molecule is coaxially accommodated with its acetyl group at the O6 side in the host cavity while the other guest molecule is located in an intermolecular space between host molecules which are stacked to form a head-to-tail channel-type packing structure along the a axis.  相似文献   
113.
采用在经典离子晶体作用势中附加Morse势,并进行必要的量子化修正,对α-quartz型GeO2结构随压力变化特性,进行分子动力学计算模拟,获得了在压力高于6.0 GPa, α-quartz型GeO2从晶相向非晶相相变的模拟结果,并利用其摩尔体积变化、键角、径向分布、配位数等重要信息对模拟结果作了深入的探讨;相变后的非晶相,由占体积66%的八面体结构和33%的四面体结构组成的非晶体,其中还有极少量的α-quartz型GeO2存在。  相似文献   
114.
Summary: Temperature rising elution fractionation (TREF) has been regarded as a powerful technique for study of semicrystalline polymers. In this paper, two examples of unique applications of TREF were introduced. One was the study on the influence of extraction of internal donor on the variation of isospecific active sites of a MgCl2- supported Ziegler catalyst, and the other was the estimation of the relationship between polymer micro-tacticity and degradation rate of isotactic polypropylene (iPP). The former example revealed the conversion from high to low isospecific site by the extraction of internal donors, whereas the latter showed a negative correlation between the level of isotacticity and the degradation rate. These results demonstrated that TREF was useful in these research applications.  相似文献   
115.
Through experimentation and analysis of the cyclotron resonance, the [110] arm in the electron Fermi surface of lead has been found to be a corrugated cylinder having different shapes of longitudinal cross section cut by various planes including the axis of the arm. The resonance amplitude of the orbit ζ on the [110] arm is also dependent on the crystallographic differences of the surfaces, even for the same orientation of the magnetic field. The best fitting of the theoretical overall line shape to the observed one of the orbit ζ has been obtained by considering the decrease of relaxation time for higher indices of harmonic resonance. The second and third harmonics are well understood in terms of the theory of surface impedance by Chambers and by Tsuji et al. The rapid broadening of the line shapes of much higher harmonics is attributed to the relation between the cyclotron orbit radius and the range of dislocation strain field. Identification of the orbit ω has been also made.  相似文献   
116.
117.
In this study, we investigate the performance of a high-efflciency KNSBN:Cu double phase-conjugate mirror (DPCM). A phase-conjugate transmissivity as high as 58% and a phase-conjugate reflectivity as high as fivefold are observed. Experimental results also show that the DPCM has a good fidelity of phase-conjugate image. Also, amplified phase-conjugate images are observed.  相似文献   
118.
Summary A sampling method of bulk precipitations for assessing the atmospheric environment and an emission spectrographic method for simultaneous determinations of trace elements were investigated 17.0 mg of carbon powder containing the internal standards (Pd and Ge) were mixed with 3.0 mg of the sample ash and burnt until the whole mixture volatized in a dc-arc (300 V, 12 A) generated in argon (5 l/min) and oxygen (2 l/min) atmosphere. The middle part (1 mm) of the arc was passed through the spectrograph slit by midway focusing method. The matrix effects of 8 major elements on minor elements were negligible. Analytical results of 14 elements agreed well with those of other methods, and the reproducibility for 24 elements have been observed to vary between ±5.0 and 17%. When the contents of 8 elements in human tissues, bulk precipitations and foodstuffs analyzed by this method were correlated with other methods, the correlation coefficients were 0.95±0.01. For sampling bulk precipitations over a long period a container with polyethylene funnel fitted with filter paper to avoid contamination due to dry fallout was used. Acid was placed in the container to prevent adsorption on the wall.
Simultanbestimmung von über 20 Elementen in Niederschlägen und biologischen Geweben mit Hilfe der Emissionsspektrographie
Zusammenfassung Für die Probenahme der Gesamtniederschläge im Rahmen von Umweltuntersuchungen wurde eine Methode untersucht, ebenso wurde ein spektrographisches Verfahren für die Bestimmung von über 20 Elementen ausgearbeitet. Bei dem Verfahren werden 17,0 mg Kohlepulver, das die inneren Standards Pd und Ge enthält, mit 3,0 mg von der Probenasche vermischt und bis zur vollständigen Verflüchtigung in einem Gleichstrombogen (300 V, 12 A) abgebrannt (Argon 5 l/min, Sauerstoff 2 l/min). Der mittlere Teil des Bogens (1 mm) wird nach der Methode der Halbweg-Fokusierung durch den spektrographischen Spalt geleitet. Die Matrixeffekte von 8 Hauptelementen gegenüber den kleineren Bestandteilen waren vernachlässigbar. Für 14 Elemente zeigten sich gute Übereinstimmungen mit anderen Methoden. Die Reproduzierbarkeit von 24 Elementen lag im Bereich von ±5–17%. Beim Vergleich der Ergebnisse für 8 Elemente in Humangewebe, Niederschlägen und Nahrungsmitteln ergaben sich Korrelationskoeffizienten von 0,95±0,01. Zur Probenahme von Niederschlägen über einen längeren Zeitraum hat sich ein Behälter mit Polyethylentrichter bewährt, der mit Filterpapier zur Verhinderung von Verunreinigungen versehen war. In den Behälter wurde zur Vermeidung von Adsorption an den Wänden Säure gegeben.
  相似文献   
119.
Thioamide dianions were generated by the highly efficient reaction of N-benzyl thioamides with 2 equiv of BuLi. Alkylation, allylation, and silylation took place selectively at the carbon atom adjacent to the nitrogen atom of the thioamide dianions. Oxiranes and an aldehyde were also used as electrophiles in the reaction of thioamide dianions to form N-thioacyl 1,3- or 1,2-amino alcohols. The insertion reaction of elemental sulfur to a thioamide dianion and subsequent ethylation afforded a N-thioacyl hemithioaminal. NMR studies on the thioamide mono- and dianions derived from N-benzyl 2-methoxythiobenzamide showed a linear relationship between the chemical shifts of all carbon atoms of thioamide mono- and dianions. The results also suggested that the negative charge at the benzylic carbon atom of the dianion is not fully delocalized. The charge distribution patterns of the dianion are consistent with those of pi polarization.  相似文献   
120.
This paper is concerned with the problem of estimating a matrix of means in multivariate normal distributions with an unknown covariance matrix under invariant quadratic loss. It is first shown that the modified Efron-Morris estimator is characterized as a certain empirical Bayes estimator. This estimator modifies the crude Efron-Morris estimator by adding a scalar shrinkage term. It is next shown that the idea of this modification provides a general method for improvement of estimators, which results in the further improvement on several minimax estimators. As a new method for improvement, an adaptive combination of the modified Stein and the James-Stein estimators is also proposed and is shown to be minimax. Through Monte Carlo studies of the risk behaviors, it is numerically shown that the proposed, combined estimator inherits the nice risk properties of both individual estimators and thus it has a very favorable risk behavior in a small sample case. Finally, the application to a two-way layout MANOVA model with interactions is discussed.  相似文献   
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