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991.
可消除热零点漂移的双压阻半桥压力传感器 总被引:1,自引:0,他引:1
提出一种可消除热零点漂移的压阻式压力传感器。该传感器由两个压阻半桥构成。两个“半桥”受力时输出信号的极性相反,而零压时输出信号极性相同。两桥输出信号相减后,其压敏输出与一个压阻全桥的输出值相同,而随温度变化的零压输出则相互抵消。模拟实验显示出预期效果 相似文献
992.
993.
994.
高炉锰铁液固态的锰磷成分差异 总被引:1,自引:1,他引:0
用数理统计方法对大量生产记录数据进行了分析核对,确认高炉锰铁在液、固两种状态时,锰、磷成分存在着差异这一事实。并确定了固态锰铁含锰量降低、含磷量增加的成分劣化区间为:锰的平均降低值在-0.275%和 0.022%之间,磷的平均升高值在-0.0015%和 0.0171%之间。按GB7730.1-7730.4-87规定与允许化验误差比较分析,也有一定超差比例存在。 相似文献
995.
The technique of group psychotherapy has recently been introduced to the practice in self-assertiveness training group. This study aims to assess various group factors that are hypothesized to be effective in the group process in a self-assertive group. Subjects of the study were participants in a 13-member self-assertiveness training group, with 4 female nurses and 8 male employees and 1 male student. The average age of this group was 35.2 years. Assessment of the group was based on Yalom's concept of twelve therapeutic factors in the group process. The results showed that 'identification', 'The existential factor' and 'interpersonal learning-input' were the three most important factors demonstrated during the group process. There were no significant age and gender differences in the above 'identification' and 'existential' factors. However, different beneficial factors were found for each group: for subjects aged 40 and above and males, it was 'interpersonal learning-output'; while in those with aged under 40 and females, 'universality' was more important than 'interpersonal learning-input'. Comparison of therapeutic factors among different groups was attempted. The above results were found different from patient groups, or the groups of university students. The discrepancy is due to different composition and tasks of each group. 相似文献
996.
HC112市内电话维护管理系统 总被引:1,自引:0,他引:1
本文介绍了市内电话维护管理系统体系结构的层次模型,讨论了各组成部分的关键技术及层间关系,给出了一种基于局域网和广域网的HC112(Hypo Centralized112)的实现。 相似文献
997.
SH Willis AH Rux C Peng JC Whitbeck AV Nicola H Lou W Hou L Salvador RJ Eisenberg GH Cohen 《Canadian Metallurgical Quarterly》1998,72(7):5937-5947
Previously, we showed that truncated soluble forms of herpes simplex virus (HSV) glycoprotein D (gDt) bound directly to a truncated soluble form of the herpesvirus entry mediator (HveAt, formerly HVEMt), a cellular receptor for HSV. The purpose of the present study was to determine the affinity of gDt for HveAt by surface plasmon resonance and to compare and contrast the kinetics of an expanded panel of gDt variants in binding to HveAt in an effort to better understand the mechanism of receptor binding and virus entry. Both HveAt and gDt are dimers in solution and interact with a 2:1 stoichiometry. With HveAt, gD1(306t) (from the KOS strain of HSV-1) had a dissociation constant (KD) of 3.2 x 10(-6) M and gD2(306t) had a KD of 1.5 x 10(-6) M. The interaction between gDt and HveAt fits a 1:1 Langmuir binding model, i.e., two dimers of HveAt may act as one binding unit to interact with one dimer of gDt as the second binding unit. A gD variant lacking all signals for N-linked oligosaccharides had an affinity for HveAt similar to that of gD1(306t). A variant lacking the bond from cysteine 1 to cysteine 5 had an affinity for HveAt that did not differ from that of the wild type. However, variants with double cysteine mutations that eliminated either of the other two disulfide bonds showed decreased affinity for HveAt. This result suggests that two of the three disulfide bonds of gD are important for receptor binding. Four nonfunctional gDt variants, each representing one functional domain of gD, were also studied. Mutations in functional regions I and II drastically decreased the affinity of gDt for HveAt. Surprisingly, a variant with an insertion in functional region III had a wild-type level of affinity for HveAt, suggesting that this domain may function in virus entry at a step other than receptor binding. A variant with a deletion in functional region IV [gD1(Delta290-299t)] exhibited a 100-fold enhancement in affinity for HveAt (KD = 3.3 x 10(-8) M) due mainly to a 40-fold increase in its kinetic on rate. This agrees with the results of other studies showing the enhanced ability of gD1(Delta290-299t) to block infection. Interestingly, all the variants with decreased affinities for HveAt exhibited decreased kinetic on rates but only minor changes in their kinetic off rates. The results suggest that once the complex between gDt and HveAt forms, its stability is unaffected by a variety of changes in gD. 相似文献
998.
HC Hung WC Chen Y Chao MC Hou HC Lin FY Chang SD Lee 《Canadian Metallurgical Quarterly》1998,93(12):2603-2604
Complication of endoscopic variceal injection sclerotherapy for esophageal variceal hemorrhage is not unusual. However, sclerotherapy complicated panophthalmitis was never reported before. We report such an unusual complication and discuss its possible mechanism and treatment. 相似文献
999.
回转窑是直接还原铁厂的主体设备,因为回转窑是分段制造,在安装现场组装焊接成一体的,所以,在回转窑的安装中,保证各段窑壳的同心度是施工的一个关键环节。本文主要介绍回转窑安装中如何定心找正,确保回转窑同心度的方法。 相似文献
1000.
The immobilization of DNA on the self-assembled monolayer of 3-aminopropyltrimethoxysilane (APTES) on mica wafer functionalized with glutaraldehyde (GA) by chemical bonding was studied by atomic force microscopy (AFM). The DNA used for our investigation was amplified by polymerase chain reaction, and primers were labeled with a -NH2 group at their 5' terminus. The surfaces were analyzed by X-ray photoelectron spectroscopy (XPS) and AFM. Results from XPS and AFM showed that the mica with the APTES and activated with GA can be formed, and the flatness of the mica can be adapted for AFM images. We found that the modified surface was capable of binding DNA molecules so that it withstood a thorough rinsing with a solution of sodium dodecylsulfate. Covalent binding between the aldehyde-terminated membrane and -NH2 groups at both ends of double-stranded DNA resulted in immobilization and straightening of the DNA. 相似文献