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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Bibliometric analysis of tsunami research 总被引:3,自引:0,他引:3
The use of the bibilometric analytical technique for examining tsunami research does not exist in the literature. The objective
of the study was to perform a bibliometric analysis of all tsunami-related publications in the Science Citation Index (SCI).
Analyzed parameters included document type, language of publication, publication output, authorship, publication patterns,
distribution of subject category, distribution of author keywords, country of publication, most-frequently cited article,
and document distribution after the Indonesia tsunami. The US and Japan produced 53% of the total output where the seven major
industrial countries accounted for the majority of the total production. English was the dominant language, comprising 95%
of articles. A simulation model was applied to describe the relationship between the number of authors and the number of articles,
the number of journals and the number of articles, and the percentage of total articles and the number of times a certain
keyword was used. Moreover the tsunami publication patterns in the first 8 months after the Indonesia tsunami occurred on
26 December 2004 indicated a high percentage of non-article publications and more documents being published in journals with
higher impact factors. 相似文献
42.
R Albrecht TC Awes C Baktash P Beckmann F Berger R Bock G Claesson G Clewing L Dragon A Eklund RL Ferguson A Franz S Garpman R Glasow HA Gustafsson HH Gutbrod J Idh P Jacobs K Kampert BW Kolb P Kristiansson IY Lee H Loehner I Lund FE Obenshain A Oskarsson I Otterlund T Peitzmann S Persson F Plasil AM Poskanzer M Purschke H Ritter S Saini R Santo HR Schmidt T Siemiarczuk SP Sorensen E Stenlund ML Tincknell GR Young 《Canadian Metallurgical Quarterly》1991,44(6):2736-2752
43.
C. T. Ho 《Journal of Materials Science》1996,31(21):5781-5786
Nickel and copper were deposited over brominated, surface treated, and pristine P-100 carbon fibres using cementation and electroplating techniques. The fibres were brominated by bromine vapour for 48 h and then desorbed at 200 °C in air for 12 h. The anodic oxidation treatment of the fibres involved electrochemical etching in a dilute sodium hydroxide electrolyte for 3 min. Electroplated coated fibres showed better tensile properties than cementation coated fibres. In addition, nickel coating exhibited better bonding with the carbon fibres compared to copper coating. The effect of bromination and surface treatment was improved adhesion between coating and fibres. Nickel- and copper-coated fibres, which were brominated, anodically oxidized, and pristine, reinforced tin-lead alloy composites were fabricated by squeeze casting. The composites containing coated treated carbon fibres had higher tensile and shear strength than the ones containing coated pristine carbon fibres. Moreover, the composite with coated brominated carbon fibres had better tensile strength and shear strength than the surface treatment. The results also showed the composites containing nickel-coated fibres had higher tensile and shear strength than the ones containing copper-coated fibres. 相似文献
44.
Because T cells appear to modulate the severity of murine Borrelia burgdorferi infections, we decided to examine the possible involvement of T cell-associated cytokines in disease outcome. Comparison of in vitro B. burgdorferi Ag-induced cytokine production in disease-susceptible and -resistant strains revealed striking differences; spleen cells from susceptible C3H mice produced significantly higher levels of IL-2 and IFN-gamma and lower levels of IL-4 than spleen cells from resistant BALB/c mice. Lymph node responses were even more divergent, with C3H mice producing high levels of IFN-gamma, and BALB/c mice producing little or none. This apparent Th1/Th2 cytokine imbalance was also reflected in vivo, since serum from C3H had significantly higher levels of B. burgdorferi-specific IgG2a Ab and lower levels of IgG1 Ab than serum from BALB/c mice. In vivo studies confirmed the importance of IL-4 in early control of spirochete growth, since treatment of either strain with neutralizing anti-IL-4 mAb led to increased joint swelling and higher spirochete burdens in joints compared with those in control mAb-treated mice. In contrast, IFN-gamma may hinder early control of spirochete growth in susceptible C3H mice, since treatment of mice with neutralizing anti-IFN-gamma mAb reduced both joint swelling and joint spirochete burdens compared with those in control mAb-treated mice. These studies indicate opposing roles for IL-4 and IFN-gamma in the modulation of spirochete growth and disease development in B. burgdorferi-infected mice and suggest that differential cytokine production early in infection may contribute to strain-related differences in susceptibility. 相似文献
45.
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47.
In multiple pregnancies, survival of remaining fetuses after premature death and delivery of one fetus is uncommon. We report a case of a triplet pregnancy that was reduced to twins at the 14th gestational week and then had preterm premature rupture of membranes and intrauterine fetal death of one twin at the 17th gestational week. To save the surviving fetus, delivery of the dead fetus and ligation of the umbilical cord at the cervical level were performed. We also performed McDonald cervical cerclage to keep the placenta of the dead fetus as well as that of the surviving one in the uterine cavity. After a series of aggressive procedures, including immediate administration of tocolytic agents, and antibiotic prophylaxis to prevent infection and preterm labor, the surviving fetus was delivered vaginally 73 days later due to intractable uterine contractions. After a 10-week hospital stay, the infant boy, weighing 2,500 g, was discharged without any sequelae. To our knowledge, this was the longest interval between deliveries in a triplet pregnancy reported in Taiwan. With adequate intensive management, a satisfactory outcome of the fetus and mother in such cases is possible. 相似文献
48.
X. Zhang J.R. Ho C.P. Grigoropoulos 《International Journal of Heat and Mass Transfer》1996,39(18):3835-3844
Heat and mass transfer at the nanosecond time scale and the nanometer length scale in pulsed laser fabrication of ultra-shallow p+-junctions is studied in this work. A new technique is developed to fabricate the ultra-shallow p+-junctions with pulsed laser doping of crystalline silicon with a solid spin-on-glass (SOG) dopant, through the nanosecond pulsed laser heating, melting, and boron mass diffusion in the 100 nm thin silicon layer close to the surface. High boron concentration of 1020 atoms cc−1 and the ‘box-like’ junction profile are achieved. The key mechanism determining the ‘box-like’ junction shape is found to be the melt-solid interface limited diffusion. The ultra-shallow p+-junctions with the depth from 30 to 400 nm are successfully made by the excimer laser. The optimal laser fluence condition for SOG doping is found about 0.6–0.8 J cm−2 by studying the ultra-shallow p+-junction boron profiles measured by the secondary ion mass spectroscopy (SIMS) vs the laser fluence and the pulse number. The one-dimensional numerical analysis agrees reasonably with the experiment, within the available physical picture. Possible mechanisms such as boron diffusivity dependence on the dopant concentration in the molten silicon are proposed. 相似文献
49.
JJ Bull MR Badgett HA Wichman JP Huelsenbeck DM Hillis A Gulati C Ho IJ Molineux 《Canadian Metallurgical Quarterly》1997,147(4):1497-1507
Replicate lineages of the bacteriophage phiX 174 adapted to growth at high temperature on either of two hosts exhibited high rates of identical, independent substitutions. Typically, a dozen or more substitutions accumulated in the 5.4-kilobase genome during propagation. Across the entire data set of nine lineages, 119 independent substitutions occurred at 68 nucleotide sites. Over half of these substitutions, accounting for one third of the sites, were identical with substitutions in other lineages. Some convergent substitutions were specific to the host used for phage propagation, but others occurred across both hosts. Continued adaptation of an evolved phage at high temperature, but on the other host, led to additional changes that included reversions of previous substitutions. Phylogenetic reconstruction using the complete genome sequence not only failed to recover the correct evolutionary history because of these convergent changes, but the true history was rejected as being a significantly inferior fit to the data. Replicate lineages subjected to similar environmental challenges showed similar rates of substitution and similar rates of fitness improvement across corresponding times of adaptation. Substitution rates and fitness improvements were higher during the initial period of adaptation than during a later period, except when the host was changed. 相似文献
50.