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991.
A thorough understanding of the magnetocaloric properties of existing magnetic refrigerant materials has been an important issue in magnetic refrigeration technology. This paper reviews a new class of magnetocaloric material, that is, the ferromagnetic perovskite manganites (R1−xMxMnO3, where R=La, Nd, Pr and M=Ca, Sr, Ba, etc.). The nature of these materials with respect to their magnetocaloric properties has been analyzed and discussed systematically. A comparison of the magnetocaloric effect of the manganites with other materials is given. The potential manganites are nominated for a variety of large- and small-scale magnetic refrigeration applications in the temperature range of 100–375 K. It is believed that the manganite materials with the superior magnetocaloric properties in addition to cheap materials-processing cost will be the option of future magnetic refrigeration technology. 相似文献
992.
Difluorocarbene reacts with 2-methoxy and 2-carbomethoxy-7,7-dimethylnorbornadiene to give homo-1,4 adducts only. The relative rates of addition are compared with that for 7,7-dimethylnorbornadiene and are found to be 2.63, 0.045 and 1.0 respectively. Consequently, an electrophilic process is operating. Difluoro, dichloro and dibromocarbenes react with 7,7-dimethylnorbornadiene exclusively on the endo face to give 1,2 and homo-1,4 adducts in ratios of ≈0.1, 0.5 and 0.7 respectively. The homo-cheletropic reaction, compared to the competing cyclopropanation, is increasingly sensitive to the bulk of the carbene partner. 相似文献
993.
L.A. Schaller L. Schellenberg T.Q. Phan G. Piller A. Ruetschi H. Schneuwly 《Nuclear Physics A》1982,379(3):523-535
Muonic X-ray energies of the K-series of the carbon isotopes 13C and 14C have been determined relative to 12C. For the first time, muonic atom measurements using radioactive 14C have been performed. Model-independent equivalent nuclear charge radii Rk,α and their differences have been deduced. The Rk,α radii increase by 10(14) and 32(11) am respectively with the filling of the neutron Subshell. The results are compared with recent elastic electron scattering data. The former natural carbon data have been reanalysed using a new value for the nuclear polarization. In terms of the rms charge radius, we then obtain for the 12C isotope. 相似文献
994.
995.
Billia B Bergeon N Thi HN Jamgotchian H Gastaldi J Grange G 《Physical review letters》2004,93(12):126105
The dynamical interaction between columnar interface microstructure and self-stress, resulting in unforeseen mechanical deformation phenomena, is brought to light by means of in situ and real-time synchrotron x-ray topography during directional solidification of dilute aluminum alloys. Beyond long-known local mechanical stresses, global mechanical constraints are found to be active. In particular, column rotation results from deformation caused by the mechanical moments associated with the very growth shape, namely, the cumulative torque acting together with the cumulative bending moment under gravity. A basic model allowing for a qualitative explanation of the observed distinctive features of the self-stress effects on microstructure dynamics is proposed. 相似文献
996.
Tra Nguyen Thanh Thuy Nguyen Ngoc Nhu Van Tuyen Nguyen Ha Nguyen Thi Thu Anh Le Thi Tu Son Ninh The 《Chemistry of Natural Compounds》2022,58(4):607-609
Chemistry of Natural Compounds - Phytochemical investigation of the ethyl acetate extract of Styrax annamensis leaves has led to the isolation and determination of a new lignan,... 相似文献
997.
Gibadullina E. M. Thu Nguyen Thi Azmukhanova R. R. Burilov A. R. Pudovik M. A. Strelnik A. G. 《Russian Journal of Organic Chemistry》2017,53(3):465-467
Russian Journal of Organic Chemistry - Dialkyl [(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-ylidene)methyl]phosphonates reacted with 2,2′-[1,3-phenylenebis(oxy)]di(ethan-1-amine)... 相似文献
998.
This paper analyzes the stability of the elastic rectangular thin plates with sinusoidal changes in the plate thickness. The buckling load is defined in a weighted residual approach for different boundary conditions. The influence of the plate thickness variation and the edge ratio on the critical loads is investigated. The results are compared to the case of uniform thickness. 相似文献
999.
Joo-Eun Lee Fang Bo Nguyen Thi Thanh Thuy Jaewoo Hong Ji Shin Lee Namki Cho Hee Min Yoo 《Molecules (Basel, Switzerland)》2021,26(1)
This study explores the potential anticancer effects of lesbicoumestan from Lespedeza bicolor against human leukemia cancer cells. Flow cytometry and fluorescence microscopy were used to investigate antiproliferative effects. The degradation of mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) was evaluated using immunoprecipitation, Western blotting, and confocal microscopy. Apoptosis was investigated using three-dimensional (3D) Jurkat cell resistance models. Lesbicoumestan induced potent mitochondrial depolarization on the Jurkat cells via upregulated expression levels of mitochondrial reactive oxygen species. Furthermore, the underlying apoptotic mechanisms of lesbicoumestan through the MALT1/NF-κB pathway were comprehensively elucidated. The analysis showed that lesbicoumestan significantly induced MALT1 degradation, which led to the inhibition of the NF-κB pathway. In addition, molecular docking results illustrate how lesbicoumestan could effectively bind with MALT1 protease at the latter’s active pocket. Similar to traditional 2D cultures, apoptosis was markedly induced upon lesbicoumestan treatment in 3D Jurkat cell resistance models. Our data support the hypothesis that lesbicoumestan is a novel inhibitor of MALT1, as it exhibited potent antiapoptotic effects in Jurkat cells. 相似文献
1000.
Hoang Thi Hong Anh Esmaeil Shahsavari Nathan J. Bott Andrew S. Ball 《Molecules (Basel, Switzerland)》2021,26(11)
Although axenic microbial cultures form the basis of many large successful industrial biotechnologies, the production of single commercial microbial strains for use in large environmental biotechnologies such as wastewater treatment has proved less successful. This study aimed to evaluate the potential of the co-culture of two halophilic bacteria, Marinirhabdus sp. and Marinobacter hydrocarbonoclasticus for enhanced protease activity. The co-culture was significantly more productive than monoculture (1.6–2.0 times more growth), with Marinobacter hydrocarbonoclasticus being predominant (64%). In terms of protease activity, enhanced total activity (1.8–2.4 times) was observed in the co-culture. Importantly, protease activity in the co-culture was found to remain active over a much broader range of environmental conditions (temperature 25 °C to 60 °C, pH 4–12, and 10–30% salinity, respectively). This study confirms that the co-culturing of halophilic bacteria represents an economical approach as it resulted in both increased biomass and protease production, the latter which showed activity over arange of environmental conditions. 相似文献