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排序方式: 共有241条查询结果,搜索用时 15 毫秒
1.
The thermodynamic functions of the pure Co were assessed using CALPAHD method for the third generation thermodynamic databases. To model the magnetic properties of the cobalt, a two-state magnetic model was accounted for the fcc phase. Calculated results were compared with the experimental information and a good fit to the experimental data was achieved. 相似文献
2.
Nicole Jacqueline Jensen Helena Zander Wodschow Malin Nilsson Jrgen Rungby 《International journal of molecular sciences》2020,21(22)
Under normal physiological conditions the brain primarily utilizes glucose for ATP generation. However, in situations where glucose is sparse, e.g., during prolonged fasting, ketone bodies become an important energy source for the brain. The brain’s utilization of ketones seems to depend mainly on the concentration in the blood, thus many dietary approaches such as ketogenic diets, ingestion of ketogenic medium-chain fatty acids or exogenous ketones, facilitate significant changes in the brain’s metabolism. Therefore, these approaches may ameliorate the energy crisis in neurodegenerative diseases, which are characterized by a deterioration of the brain’s glucose metabolism, providing a therapeutic advantage in these diseases. Most clinical studies examining the neuroprotective role of ketone bodies have been conducted in patients with Alzheimer’s disease, where brain imaging studies support the notion of enhancing brain energy metabolism with ketones. Likewise, a few studies show modest functional improvements in patients with Parkinson’s disease and cognitive benefits in patients with—or at risk of—Alzheimer’s disease after ketogenic interventions. Here, we summarize current knowledge on how ketogenic interventions support brain metabolism and discuss the therapeutic role of ketones in neurodegenerative disease, emphasizing clinical data. 相似文献
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4.
Semiconductors - The transformation of a two-dimensional GaN layer into three-dimensional islands (2D–3D transition) under increasing temperature in a flow of ammonia is investigated... 相似文献
5.
Jian Zhao Linkun Shi Malin Liu Jiaxing Chang Youlin Shao Bing Liu Rongzheng Liu 《International Journal of Applied Ceramic Technology》2022,19(5):2514-2522
Dense sintering of SiC nanopowder under low temperature and pressure remains a big challenge, because of the great resistance caused by the severe agglomeration of nanopowder. A novel sintering strategy is proposed to prepare SiC composite ceramics by sintering the mixture of SiC nanopowder and SiC micron powder at low temperature and pressure. The SiC micron powder was in the size of 100 µm with little sintering activity, which was designed as a pressure conductor to promote the densification of SiC nanopowder. Experimental results showed that the SiC micron powder had a significant effect on increasing of the sintering density of nanopowder and improving the mechanical properties of SiC ceramics. An SiC composite ceramic with a relative density of 98%, a Vickers hardness of 22.6 GPa, and a fracture toughness of 5.43 MPa m1/2 could be sintered by spark plasma sintering under 1700°C and 30 MPa by adding 30 wt.% 100 µm SiC micron powder as reinforcements. 相似文献
6.
T. V. Malin D. S. Milakhin V. G. Mansurov Yu. G. Galitsyn A. S. Kozhuhov V. V. Ratnikov A. N. Smirnov V. Yu. Davydov K. S. Zhuravlev 《Semiconductors》2018,52(6):789-796
The effect of atomic aluminum deposited onto sapphire substrates with different nitridation levels on the quality of AlN layers grown by ammonia molecular-beam epitaxy is investigated. The nitridation of sapphire with the formation of ~1 monolayer of AlN is shown to ensure the growth of layers with a smoother surface and better crystal quality than in the case of the formation of a nitrided AlN layer with a thickness of ~2 monolayers. It is demonstrated that the change in the duration of exposure of nitrided substrates to the atomic aluminum flux does not significantly affect the parameters of subsequent AlN layers. 相似文献
7.
双歧杆菌发酵中国黑米口服液的研制 总被引:5,自引:0,他引:5
以中国黑米为主要原料,制作发酵培养基,采用耐氧两歧双歧杆菌进行发酵扩大培养,以双歧杆菌发酵中国黑米口服液。应用该口服液对腹泻、消化不良病人进行治疗观察,疗效明显 相似文献
8.
D. F. Malin 《成像科学杂志》2013,61(3):87-94
A simple, non-destructive method of image intensification and reduction is described which can be applied to continuous-tone negative materials. The method employs a commercially available direct copy (reversal) film whose contrast (γ) can be continuously varied by pre-exposure from 0.8 to ~ 10.0. This film is then used with a difTuse-light contact printer to extract images from negatives which have been severely under- or over-exposed. Examples of images extracted from Plus-X negatives which have received from eight SlOps over- to seven stops underexposure are shown. This same process can be used to retrieve usable images from exposures where the chemical or image fog levels approach developed densities of 5.0. The technique compares favourably with the complicated autoradiographic procedures recently introduced for thin negative enhancement but is not affected by high levels of chemical fog. It appears that the process is versatile enough to replace traditional chemical methods of photographic intcnsification and reduction. 相似文献
9.
Purhagen JK Sjöö ME Eliasson AC 《Journal of the science of food and agriculture》2012,92(6):1201-1213
BACKGROUND: The use of dietary fibre in bread products is increasing because of consumer demand for healthier products. However, an increase in dietary fibre level changes the rheological properties of the dough and also the quality properties of the final bread product. In this study, effects on dough and bread staling were followed after replacing 3% of wheat flour by fibre‐rich additives (fine durum, oat bran, rye bran and wheat bran). Free‐standing and pan‐baked loaves were baked to compare the influence of baking method and loaf shape. RESULTS: All additives increased dough stability, with oat bran giving the greatest stability and longest development time. Parameters measured during storage were distribution, migration and loss of water, cutability, crumbliness, firmness and springiness. Furthermore, amylopectin retrogradation and amylase‐lipid complex formation were assessed. Oat bran provided similar or better results than the control for all staling parameters, while other additives gave no general improvements. Cutability reached a plateau when crumb firmness was ≥ 4 N. CONCLUSION: Small amounts of fibre‐rich additives had a significant influence on staling. However, the baking method (free‐standing or pan‐baked bread) had a greater impact on staling than the additives, thus displaying the importance of the baking method. Cutability was found to be related to firmness. Copyright © 2011 Society of Chemical Industry 相似文献
10.
Malin Borg Eric Lefebvre Mikael Malmkvist Ludovic Desplanque Xavier Wallart Yannick Roelens Gilles Dambrine Alain Cappy Sylvain Bollaert Jan Grahn 《Solid-state electronics》2008,52(5):775-781
The effect of gate-length variation on DC and RF performance of InAs/AlSb HEMTs, biased for low DC power consumption or high gain, is reported. Simultaneously fabricated devices, with gate lengths between 225 nm and 335 nm, have been compared. DC measurements revealed higher output conductance gds and slightly increased impact ionization with reduced gate length. When reducing the gate length from 335 nm to 225 nm, the DC power consumption was reduced by approximately 80% at an fT of 120 GHz. Furthermore, a 225 nm gate-length HEMT biased for high gain exhibited an extrinsic fT of 165 GHz and an extrinsic fmax of 115 GHz, at a DC power consumption of 100 mW/mm. When biased for low DC power consumption of 20 mW/mm the same HEMT exhibited an extrinsic fT and fmax of 120 GHz and 110 GHz, respectively. 相似文献