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91.
92.
A CWDM is proposed for fiber optic communication networks. The OADM is designed based on SOI structure. The scheme for CWDM optical signal protection is presented. 相似文献
93.
Leakage currents through In/MgO/n-type Si/In structures were studied. The electrical conduction investigations suggest that the leakage behavior is governed by the Schottky (Poole-Frenkel) emission for the gate (substrate) injection. This is because of strong leakage current dependent on the interfacial property of devices. It is shown that the discrepancy in the MgO permittivity extracted from the Schottky and Poole-Frenkel emissions is due to the formation of intermediate MgSixOy layer. 相似文献
94.
Substituted acetophenone 1 in BMImPF6 ionic liquid, heated at 120 °C for 24 h, produces β‐methylchalcone 2 , triarylbenzene 3 , and triarylpyrylium salt 4. BMImPF6 catalyzes the self‐aldol condensation of 1 , whose cyclotrimerization gives an increased conversion to 4 at the expense of 3 normally obtained from the cyclotrimerization of 1 in common organic solvent. 相似文献
95.
Monoclonal antibodies (mAbs) of the IgM isotypes were produced from mice immunized with blood forms ofTrypansoma cruzi Y strain. Characterization of the epitope recognized by one of the mAbs, 164C11, as well as the effects of this mAb on complement-mediated
lysis and host cell invasion are reported. Immunocytochemical analysis showed that the mAb was reactive with various strains
ofT. cruzi (Y, WSL, and Colombiana) as well as other trypanosomatids. The mAb 164C11 demonstrated a high complement-mediated lytic activity
against bloodstream trypomastigotes, being more effective than chronic mouse serum. A protein with an apparent molecular weight
of 72 kDa was detected by this mAb on all developmental stages ofT. cruzi. Studies using periodate and endoglycosidase treatments suggested that the epitope is not a carbohydrate and seems to be
located on the parasite membrane. In addition, preliminary results are presented, suggesting that the72-kDa protein is involved in adhesion/or internalization of bloodstream trypomastigotes. 相似文献
96.
A statistical linear discriminant method is used to determine if a carbon, nitrogen or oxygen atom is bonded to a monosubstituted phenyl ring. A pattern vector is developed using peak heights of each of the seventeen active infrared and sixteen active Raman bands characteristic of the ring vibration. The Sadtler Standard Raman Spectra, which includes infrared spectra, served as the data base. The success rate is compared for the use of infrared data only. Raman data only and combined infrared and Raman data normalized by several possible methods. 相似文献
97.
Marshall M. Siegel Rushung Tsao Allan Wissner 《Journal of mass spectrometry : JMS》1993,28(11):1297-1308
A series of substituted bisaryl phosphate compounds, (R1CH2)+ ArOP = O(O?)(OArR2R3), was analyzed and characterized by fast atom bombardment mass spectrometry. Abundant fragment ions were observed and correlated with the proposed structures. From fragmentation pattersn, ‘ortho effect’ reactions were demonstrated to have occurred when the phosphoryl oxygen reacted with the (CH2R1)+ and C?O(OCH3) substituents in the ortho position, relative to the phosphate group, and displaced the R1 and OCH3 groups, respectively, to produce phosphorus containing six-membered rings fused to the aryl moiety. When the (CH2R1)+ substituents were in the meta position relative to the phosphate group, the ‘ortho effect’ reactions were not observed. However, when the C?O(OCH3) substituent was in the meta position relative to the phosphate group, an abundant fragment ion containing a five-membered phosphate ring fused to the aryl ring was detected with the original phosphoryl oxygen ortho to both the phosphate oxygen and a formyl group, formed from the original C?O(OCH3) substituent. All other fragmentations not involving the ‘ortho effect’ reactions were nearly identical for the different structural isomers of the substituted bisaryl phosphate compounds. 相似文献
98.
Lee Ching-Yi Wen Jingquan Thomas Seqwana Delgass W. Nicholas Grutzner John B. Tsao George T. 《Applied biochemistry and biotechnology》1995,53(1):29-35
In theEscherichia coli cell-free system, the modification of cell extract can be achieved by preparation of the strains carrying additional property
or those being induced with a certain gene expression prior to harvesting. In this study, we analyzed the cell-free system
with S30 extract containing T7 RNA polymerases (S30 extract-T7pol) prepared from E.coli BL21(DE3) strain, which includes T7 RNA polymerase from extrinsic genes by IPTG induction, as a model for the improvement
of the cell-free system. The fact that a significant degree of mRNA degradation was observed in the cell-free system with
S30 extract-T7pol indicates the increase of ribonuclease activity was an unfavorable influence derived from the cell-extract
modification process. We also showed that this influence was settled by the addition of an effective ribonuclease inhibitor,
such as copper (II) ion, to the reaction mixture. 相似文献
99.
The purpose of this paper is to extend the TOPSIS method based on interval-valued fuzzy sets in decision analysis. Hwang and Yoon developed the technique for order preference by similarity to ideal solution (TOPSIS) in 1981. TOPSIS has been widely used to rank the preference order of alternatives and determine the optimal choice. Considering the fact that it is difficult to precisely attach the numerical measures to the relative importance of the attributes and to the impacts of the alternatives on these attributes in some cases, therefore, the TOPSIS method has been extended for interval-valued fuzzy data in this paper. In addition, a comprehensive experimental analysis to observe the interval-valued fuzzy TOPSIS results yielded by different distance measures is presented. A comparative analysis of interval-valued fuzzy TOPSIS rankings from each distance measure is illustrated with discussions on consistency rates, contradiction rates, and average Spearman correlation coefficients. Finally, a second-order regression model is provided to highlight the effects of the number of alternatives, the number of attributes, and distance measures on average Spearmen correlation coefficients. 相似文献
100.
Sulfur-substituted azido dienes 1 and 11 , conveniently prepared from the corresponding 3-sulfolenes 5 and 10 , were thermolyzed to give pyrrolizidine and indolizidine products, 6 , 7 and 14 . 相似文献