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排序方式: 共有1149条查询结果,搜索用时 125 毫秒
991.
992.
993.
A single-phase γ?-FeN film with the rock-salt structure was produced by pulsed laser deposition of Fe onto an Al substrate in a N2 atmosphere. Its Mössbauer spectra and powder X-ray diffraction patterns were measured. γ?-FeN was found to be antiferromagnetic exhibiting a hyperfine magnetic field of 30 T at a temperature of 5 K. It was found to have a Néel temperature of 220 K. A minor component with a higher hyperfine magnetic field of 49 T at 5 K was also observed. It is thought to originate from defects in γ?-FeN. 相似文献
994.
Dr. Jinying Zhang Zhen Zhu Prof. Dr. Yanquan Feng Hitoshi Ishiwata Dr. Yasumitsu Miyata Dr. Ryo Kitaura Dr. Jeremy E. P. Dahl Prof. Dr. Robert M. K. Carlson Dr. Natalie A. Fokina Prof. Dr. Peter R. Schreiner Prof. Dr. David Tománek Prof. Dr. Hisanori Shinohara 《Angewandte Chemie (International ed. in English)》2013,52(13):3717-3721
995.
996.
Kazuhiko Hashimoto Ryo Ohsawa Naohiro Imai Masahiko Okada 《Journal of polymer science. Part A, Polymer chemistry》1999,37(3):303-312
Two kinds of novel vinyl monomers having D ‐glucaric moieties leading to a new type of glycopolymeric inhibitors of β‐glucuronidase, N‐p‐vinylbenzyl‐6‐D ‐glucaramide (6 ) and potassium N‐p‐vinylbenzyl‐6‐D ‐glucaramid‐1‐ate (8 ), were synthesized by the reaction of D ‐glucaro‐6,3‐lactone (3 ) with p‐vinylbenzylamine (5 ) with no catalyst, and the subsequent treatment of the reaction mixture with acetic anhydride and potassium hydroxide aqueous solution, respectively. The radical copolymerization of 8 with acrylamide in various feed ratios at 60°C in 0.1 N potassium chloride aqueous solution gave water‐soluble copolymers (9 ) composed of a synthetic polymeric main chain and many pendant D ‐glucaric chains. The resulting glycopolymers (9 ) were found to inhibit the activity of β‐glucuronidase strongly through a model reaction with p‐nitrophenyl β‐D ‐glucuronide (10 ) in acetic buffer solution (pH 4.7). © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 303–312, 1999 相似文献
997.
Objective: To derive a clinical prediction rule for early recovery of knee range of motion after total knee arthroplasty. Methods: This prospective cohort study evaluated the data of 273 individuals undergoing primary total knee arthroplasty. The individual factors, the physical and motor function data were assessed preoperatively upon admission as a baseline survey. The knee joint extension angle and knee joint flexion angle were re-evaluated on postoperative day 14 as a follow-up. The recovery group comprised individuals with a knee joint extension angle of more than -5 degrees and knee joint flexion angle of more than 110 degrees on postoperative day 14. The other patients constituted the non-recovery group. Multivariate logistic regression analysis was used for deriving a clinical prediction rule. Results: The results indicated that the use of a cane, knee joint extension and flexion angles, and Timed Up and Go test time were significant factors for predicting early recovery of knee range of motion after total knee arthroplasty. Furthermore, a clinical prediction rule was derived and included the use of a cane, knee joint extension angle ≥ -15 degrees, knee joint flexion angle ≥ 125 degrees, and a Timed Up and Go test time < 11.2 s. A total clinical prediction rule score ≥ 8 indicated a positive likelihood ratio of more than 10 for a successful outcome and the post-test probability was approximately 95%. Conclusions: The derived clinical prediction rule might be a useful screening tool for proper postoperative goal setting and the establishment of individualized physical therapy programs. 相似文献
998.
Ewa Broclawik Ryo Yamauchi Akira Endou Momoji Kubo Akira Miyamoto 《International journal of quantum chemistry》1997,61(4):673-682
Simple functional models for elementary steps in the total oxidation of methane over supported palladium catalysts were investigated using density functional theory. Three simple cluster models were proposed, namely, the palladium dimer and PdO diatomic and linear Pd2O, to probe the mechanism of the methane activation on metallic and oxidized palladium phases, respectively. The strongest adsorption was found on Pd2, where also the C(SINGLE BOND)H bond became easily activated; however, no stable product of the C(SINGLE BOND)H bond scission was indicated. Similar hydrogen activation took place on Pd2O and, in addition, adsorbed methyl and OH species formed the most stable system after crossing a moderate energy barrier. The same product was previously found stable also in the case of PdO dimer but the activation barrier was high. On the Pd2O cluster, the process of energy barrier crossing was accomplished in two steps: easy formation of a free hydrogen moiety and actual oxidation, which made the overall process less demanding energetically. © 1997 John Wiley & Sons, Inc. 相似文献
999.
A comparison is made between two types of solid particles used in electrorheological fluids: particles with homogeneous electrical
properties versus layered particles with a semi-conducting core surrounded by an outer layer of lower conductivity. Rheological
measurements of these suspensions under steady shear and d.c. electric field show that the layered particle system produces
the same yield stress but with a substantially reduced electric current. X-ray spectroscopic analysis confirms that these
particles have a thin layer of SiOx on the outer surface which causes the reduction in conductivity. Measurement of the dielectric permittivity followed by analysis
using the Maxwell-Wagner model of polarization indicates that the conductivity of the outer layer is about 0.62 times that
of the core region.
Received: 13 January 1999 Accepted: 26 July 1999 相似文献
1000.
Ryo Ikehata 《Mathematical Methods in the Applied Sciences》2001,24(9):659-670
This paper is concerned with some uniform energy decay estimates of solutions to the linear wave equations with strong dissipation in the exterior domain case. We shall derive the decay rate such as $(1+t)E(t)\le C$\nopagenumbers\end for some kinds of weighted initial data, where E(t) represents the total energy. Our method is based on the combination of the argument due to Ikehata–Matsuyama with the Hardy inequality, which is an improvement of Morawetz method. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献