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21.
A silver palladium (Ag/Pd) alloy powder is used as an example material to illustrate potential applications of electrophoretic deposition (EPD) in electronics manufacturing, in particular the forming of multilayer devices. The dispersion and deposition of the Ag/Pd powder in acetic acid is characterized. It is found that deposition can be explained by the direct action of electrostatic force on individual particles. Depositions of this Ag/Pd powder are then used to demonstrate: forming of a continuous layer on a rigid substrate; forming of continuous layers in laminated and sintered BaTiO3 multilayers; and incorporation of patterned depositions into a multilayer by either overcasting the patterned deposition with a particulate slip to form a multicomponent tape, or direct lamination of the patterned deposition to a low temperature co-fired ceramic (LTCC) tape. It is shown that electrically conducting layers can be formed at an average thickness of only two times the diameter of the starting powder. Continuous conductor lines thirty times the average diameter of the starting powder were formed. 相似文献
22.
S. Mardnio P. Lucena Randall Q. Snurr Clio L. Cavalcante Jr. 《Microporous and mesoporous materials》2008,111(1-3):89-96
The adsorption of xylene isomers in AlPO4-11 (AEL network) was investigated using biased grand canonical Monte Carlo (GCMC) simulations. Preferential o-xylene adsorption was predicted by the simulations, in agreement with previously reported experimental data. In AlPO4-11 the selective adsorption behavior comes from the smaller length of the o-xylene molecule along the crystallographic c-axis compared to p-xylene. This is in contrast to AlPO4-5 and AlPO4-8, where the ortho-selectivity is caused by the characteristic face-to-face positioning of o-xylene. Energy minimization studies were also performed in a flexible AlPO4-11 lattice to study the structural changes upon xylene adsorption. The energy minimization study showed that the AlPO4-11 crystal distorts upon p- and o-xylene adsorption. The distortion mechanism is related to the strong interaction between xylene methyl groups and the sieve oxygen atoms in the O3 position in the wide region of the pore. 相似文献
23.
The thermal properties of a magnesium aluminium silicate (MAS) glass ceramic matrix composite reinforced by SiC (Nicalon)
fibres have been investigated before and after heat treatment in the temperature range 600–1,200 °C. Within this temperature
range, during the heat treatment at lower temperatures such as 600 and 700 °C, the oxidation of the carbon layer occurred
and mixture of silicon and carbon was formed in the interface. This results in a decrease in thermal diffusivity values. After
heat treatment at the temperatures higher than 1,000 °C, the carbon layer was thickened and resulted in the higher thermal
diffusivity values. 相似文献
24.
Power distribution systems have been significantly affected by many outage-causing events. Good fault cause identification can help expedite the restoration procedure and improve the system reliability. However, the data imbalance issue in many real-world data sets often degrades the fault cause identification performance. In this paper, the E-algorithm, which is extended from the fuzzy classification algorithm by Ishibuchi to alleviate the effect of imbalanced data constitution, is applied to Duke Energy outage data for distribution fault cause identification. Three major outage causes (tree, animal, and lightning) are used as prototypes. The performance of E-algorithm on real-world imbalanced data is compared with artificial neural network. The results show that the E-algorithm can greatly improve the performance when the data are imbalanced 相似文献
25.
Mark Taylor John Miles Dino Bouchlaghem Chimay Anumba 《Canadian Metallurgical Quarterly》2007,21(1):59-62
IT systems for engineers are becoming more numerous and complex and will further proliferate in the future. It is infeasible to expect users to be trained to work with a plethora of systems, especially as many of them will only see occasional use. Therefore, in the near future, systems will need user interfaces that allow intuitive access and usage. This paper examines a new style of user interface based on virtual reality. 相似文献
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29.
J Tyson L Tranebjaerg S Bellman C Wren JF Taylor J Bathen B Aslaksen SJ S?rland O Lund S Malcolm M Pembrey S Bhattacharya M Bitner-Glindzicz 《Canadian Metallurgical Quarterly》1997,6(12):2179-2185
The Jervell and Lange-Nielsen syndrome (JLNS) comprises profound congenital sensorineural deafness associated with syncopal episodes. These are caused by ventricular arrhythmias secondary to abnormal repolarisation, manifested by a prolonged QT interval on the electrocardiogram. Recently, in families with JLNS, Neyroud et al. reported homozygosity for a single mutation in KVLQT1 , a gene which has previously been shown to be mutated in families with dominantly inherited isolated long QT syndrome [Neyroud et al . (1997) Nature Genet ., 15, 186-189]. We have analysed a group of families with JLNS and shown that the majority are consistent with mutation at this locus: five families of differing ethnic backgrounds were homozygous by descent for markers close to the KVLQT1 gene and a further three families from the same geographical region were shown to be homozygous for a common haplotype and to have the same homozygous mutation of the KVLQT1 gene. However, analysis of a single small consanguineous family excluded linkage to the KVLQT1 gene, establishing genetic heterogeneity in JLNS. The affected children in this family were homozygous by descent for markers on chromosome 21, in a region containing the gene IsK . This codes for a transmembrane protein known to associate with KVLQT1 to form the slow component of the delayed rectifier potassium channel. Sequencing of the affected boys showed a homozygous mutation, demonstrating that mutation in the IsK gene may be a rare cause of JLNS and that an indistinguishable phenotype can arise from mutations in either of the two interacting molecules. 相似文献
30.
The purpose of this study was to examine the factors which affect the level of fatigue among patients participating in clinical trials in which this symptom had been assessed with the EORTC QLQ-C30. Data were assembled from 2390 patients in ten clinical trials in which the QLQ-C30 had been used to assess baseline and on-study quality of life. The relationship between the level of fatigue reported by the patients on the fatigue scale of this questionnaire and patient and disease characteristics was assessed in univariate and multivariate cross-sectional analyses. In addition, changes in fatigue scores were compared in a longitudinal analysis among patients on two arms of an anti-emetic trial whose emesis control was markedly different. Baseline fatigue levels differed substantially among patients taking part in the different trials. Factors associated with greater fatigue severity on univariate analysis included: female gender, presence of metastatic disease, and poorer performance status. In addition, on multivariate analyses the oldest patients were found to have less fatigue, as were patients with breast cancer, while patients with ovarian and lung cancer experienced greater fatigue. Patients on the arm of the anti-emetic trial in which emesis was better controlled showed significantly less increase in fatigue after receiving chemotherapy. The fatigue scale of the QLQ-C30 appears to provide a useful approach to assessing this important symptom. The relationships found between fatigue and patient and disease characteristics need further exploration as does the degree to which the QLQ-C30 fully captures this dimension of quality of life. 相似文献