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排序方式: 共有293条查询结果,搜索用时 484 毫秒
121.
Safe and Selective Nitro Group Reductions Catalyzed by Sustainable and Recyclable Fe/ppm Pd Nanoparticles in Water at Room Temperature 下载免费PDF全文
Jie Feng Dr. Sachin Handa Dr. Fabrice Gallou Prof. Dr. Bruce H. Lipshutz 《Angewandte Chemie (International ed. in English)》2016,55(31):8979-8983
As a result of a unique synergy between ligand‐free Fe/ppm Pd nanoparticles and PEG‐containing designer surfactants, a facile and selective reduction of nitro‐containing aromatics and heteroaromatics can be effected in water at room temperature in the presence of NaBH4. This new nanotechnology involves low catalyst loadings, is highly chemoselective, and tolerates a wide variety of functional groups. The process, which includes recycling of the entire aqueous medium, offers a general, environmentally responsible, and notably safe approach to highly valued reductions of nitro‐containing compounds. 相似文献
122.
Muneo Chō Mariko Giga Tadasi Huruya Takeaki Yamazaki 《Integral Equations and Operator Theory》2007,57(3):303-308
Let
be an invertible class A operator such that
. Then we show that
, where gT is the principal function of T. Moreover, we show that if T is pure, then
. 相似文献
123.
Dr. Sachin Handa Eric D. Slack Prof. Bruce H. Lipshutz 《Angewandte Chemie (International ed. in English)》2015,54(41):11994-11998
Nickel nanoparticles, formed in situ and used in combination with micellar catalysis, catalyze Suzuki–Miyaura cross‐couplings in water under very mild reaction conditions. 相似文献
124.
Both enantiomers of 8-oxabicyclo[3.2.1]oct-3-en-2-one (6) have been synthesized from 4-hydroxycyclohept-2-enone (3) on the basis of a novel oxidative cyclo-etherification using PhI(OH)OTs (Koser's reagent). (-)-(1S,5R)-8-Oxabicyclo[3.2.1]oct-3-en-2-one [(-)-6, 95% ee] was expeditiously transformed to (+)-sundiversifolide (1). 相似文献
125.
Yamauchi K Mimura H Kimura T Yumoto H Handa S Matsuyama S Arima K Sano Y Yamamura K Inagaki K Nakamori H Kim J Tamasaku K Nishino Y Yabashi M Ishikawa T 《J Phys Condens Matter》2011,23(39):394206
We have constructed an extremely precise optical system for hard-x-ray nanofocusing in a synchrotron radiation beamline. Precision multilayer mirrors were fabricated, tested, and employed as Kirkpatrick-Baez mirrors with a novel phase error compensator. In the phase compensator, an at-wavelength wavefront error sensing method based on x-ray interferometry and an in situ phase compensator mirror, which adaptively deforms with nanometer precision, were developed to satisfy the Rayleigh criterion to achieve diffraction-limited focusing in a single-nanometer range. The performance of the optics was tested at BL29XUL of SPring-8 and was confirmed to realize a spot size of approximately 7 nm. 相似文献
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128.
Misa Miura Kazunori Seki Osamu Ito Yasunobu Handa Masahiro Kohzuki 《Physical Therapy Research》2012,15(1):15-20
Background: Strength of the trunk muscles is a key component of motor control, but it declines easily with the process of aging and/or disuse. Objectives: To investigate the effects of surface electrical stimulation (ES) to the abdominal muscles and the motor performance for care-needing elderly. Design: Controlled trial. Participants: Twenty-one elderly people (60–90 years) with care-needing, who were admitted to a nursing home or hospital for daily care and their score of Barthel Index had been stable from 55.3 ± 19.4 to 55.3 ± 19.8 during 3 months before intervention. Intervention: Common physical/occupational therapy was performed for all of the subjects during the study period. ES was applied to the abdomen of 15 subjects (ES group) twice a day for 8 weeks. Measurements: Functional measurements were performed before and after beginning of the study with some parameters as follows: grip strength; movement time for sitting up (MSU); maximum walking speed (WS). Results: No significant differences between two groups were noted for characteristics at baseline. In the ES group, MSU (from 21.1 ± 21.4 to 10.4 ± 8.3 sec) significantly improved (p < 0.05) after 8weeks. WS (from 17.7 ± 12.1 to 24.3 ± 15.3 m/min) were also improved (p < 0.05) after 8 weeks. Limitations: A limitation of this study was the small sample size. Conclusions: ES to the abdominal area has the potential to improve motor function in the care-needing elderly through reinforcement of the abdominal muscles. 相似文献
129.
Daisuke Taniguchi Akihiro Handa Risa Kodama Yohei Okada Kazuhiro Chiba 《Electroanalysis》2019,31(12):2299-2302
Although acid/base reactions are used widely to denature proteins during food processing, the application of reduction/oxidation (redox) reactions are relatively rare in this field. Herein, we demonstrate a “redox denaturation” of proteins, using egg plasma as a model. Electrochemical treatment of egg plasma in the presence of iodide ion (I?) selectively induced intramolecular disulfide bond formations, resulting in a different type of denaturation than that achieved via heat treatment. The reaction mechanism was examined through electrochemical analysis using cyclic voltammetry. Although the involvement of hypervalent iodine (“I+”) cannot be ruled out, molecular iodine (I2) generated at the surface of anode is the most likely oxidizing agent that formed the disulfide bonds. We believe that the redox denaturation of proteins described herein would be a promising approach in food processing and can find practical applications in this field. 相似文献
130.