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排序方式: 共有398条查询结果,搜索用时 15 毫秒
121.
122.
The first recordings of the Novaya Zemlya (NZ) effect were made during Willem Barents' third Arctic expedition. Ray-tracing analyses of the three key observations, on 24-27 January 1597, show that all the reported details can be explained by adopting one common and realistic type of temperature inversion. In particular, the Moon-Jupiter conjunction could have been visible over the central mountain ridge of the island. We show that the NZ effect distorts the relative positions of Jupiter and the Moon in such a way that the looked-for fingerprint of the conjunction occurred almost 2 h after the true conjunction. The quoted direction for the apparent Moon-Jupiter conjunction is then found to be accurate to within 1 degree. This delay of the apparent conjunction largely explains the error of 29 degrees in their longitude determination. The truthfulness of these observations, debated for four centuries, now appears to be beyond doubt. 相似文献
123.
124.
L Konrad P Schiemann H Renneberg G Wennemuth C Fini G Aumüller 《Canadian Metallurgical Quarterly》1998,59(1):190-196
The factor structure of the Millon Clinical Multiaxial Inventory (Millon, 1994; MCMI-III) was assessed among 444 African American inpatient substance abusers and constitutes the first factor analysis of the MCMI-III. We found 3 main factors: General Maladjustment, Paranoid Behavior/Thinking With Detached Emotionality, and Antisocial Acting Out. These factors were essentially similar to previous findings of factor studies with the MCMI and MCMI-II across diverse populations. This factor invariance should lend credibility to the revised test and spur additional research into its psychometric properties. 相似文献
125.
R. Gunther 《Glass and Ceramics》1957,14(7):262-263
126.
In the 11 years since the first practicable operational tropo systems were developed, there has been a tremendous growth in their number and complexity. This article describes the principles and applications of tropospheric scatter communications and discusses current development trends. Included is a table listing practically all of the tropo systems installed around the world, with pertinent technical data, together with maps showing the geographic location of most systems. The maps are keyed to the table for easy reference. 相似文献
127.
The activity of immobilized glucose dehydrogenase (GDH), a typical PQQ-dependent quinoprotein, was studied qualitatively and quantitatively by scanning electrochemical microscopy (SECM). PQQ-dependent GDH is of interest because of its high activity and independence of dissolved oxygen in catalyzing the transfer of electrons from glucose to an electron mediator. Biotinylated glucose dehydrogenase was bound to streptavidin-coated paramagnetic beads (surface concentration > or = 1.8 x 10(-11) mol cm(-2)) which were deposited as microscopic microspots on a hydrophobic surface. The catalytic activity of immobilized GDH was mapped in SECM feedback mode and generation-collection mode using ferrocenemethanol, ferrocenecarboxylic acid, p-aminophenol, and ferricyanide as electron mediators, respectively. The apparent steady-state kinetics of catalysis were measured under conditions of high d-glucose concentration using the theory developed for the SECM feedback and generation collection (GC) modes. In feedback mode, curves of the kinetically controlled substrate current against normalized distance were plotted, and it was found that GDH catalysis follows pseudo-first-order kinetics. In GC mode detection, the catalysis follows zero-order kinetics in the presence of high concentration of both substrates for GDH. The turnover rate obtained for immobilized GDH is lower than that of native GDH but much higher than that generally observed for glucose oxidase. 相似文献
128.
Gunther Maier 《Scientometrics》2006,69(3):651-667
Summary This paper discusses
the relationship between Journal Impact Factors and the scientific community's
judgment of the quality of journals in regional science, a discipline closely
related to economics and geography. The paper compares the results of a survey
inquiring the quality of journals in the discipline with the impact factors of
these journals for a total of five years. The comparison shows that no
significant positive correlation between the impact factors and the peer
judgments can be found. In many cases the correlation turns out to be negative
- in some cases even significantly. 相似文献
129.
Brbel Tress Gunther Tress Henri Dcamps Anne-Marie dHauteserre 《Landscape and urban planning》2001,57(3-4)
Landscape issues are of interest in many disciplines, but they are seldom seen as an opportunity for inter- or transdisciplinary cooperation. This limits the ability to account for real world complexity. Bridging human and natural sciences intends to foster and coordinate communication about landscape-related issues—within academia and between science and society. The collection of papers in this special issue and the recommendations for future research are selected from the conference “Multifunctional Landscapes—Interdisciplinary Approaches to Landscape Research and Management” in Roskilde, Denmark, 2000. The contributions all bear evidence of an integrating approach to landscape research, bridging human and natural sciences. 相似文献
130.