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61.
Roger Chevrel Marcel Sergent Bernd Seeber Øystein Fischer Andreas Grüttner Klaus Yvon 《Materials Research Bulletin》1979,14(4):567-577
A new ternary molybdenum chalcogenide has been found with composition InxMo15Se19. This compound crystallizes in the hexagonal space group P63/m, and shows both types of blocks Mo6Se8 and Mo9Se11. To our knowledge, this is the first Me9X11 unit ever observed in a material. It presents a homogeneity domain: 2, 9 < x < 3, 4. Substitution of sulphur and tellurium for selenium in In3.3Mo15Se19-yXy (X = S, Te) is possible in the limits 0 < y < 12 and 0 < y < 2 respectively. The new compound becomes a high field superconductor at low temperature. 相似文献
62.
为了得到用于1.3μm光通讯窗口掺镨化镓铟(PGICE)高数值孔光纤,本文报道以ZrF4-BaF2-LaF3-AlF3-Na(Li)F-PbF2(ZBLAN(Li)Pb)和NaPO3-BaF2-ZnF2-PbF2(FPG)玻璃作为包层材料,研究了芯和包层玻璃在物理性质和化学组分上的匹配性,差热扫描(DSC)和电镜(SEM)分析表明PGICZ/ZBLAN(Li)Pb虽在物理性质上匹配,但在化学组分不 相似文献
63.
Patrícia Martins de Oliveira Afonso Mota Ramos Eliane Maurício Furtado Martins Érica Nascif Rufino Vieira Ariana de Souza Soares Marcel Cardoso de Noronha 《International Journal of Food Science & Technology》2017,52(12):2547-2554
This study aimed to evaluate the vacuum impregnation (VI) and soaking methods in the addition of Lactobacillus acidophilusLA‐3 to minimally processed melon (MPM). The melons were washed, sanitised in chlorine solution (200 mg L?1), peeled and cutted into cubes. Lactobacillus acidophilusLA‐3 (1.4 × 1010 CFU g?1) were added to the MPM through both techniques. The L. acidophilusLA‐3 count in MPM was similar to those commonly found in dairy products having probiotic claim, but VI was more efficient than soaking in maintaining the viability (8.61 and 7.98 Log CFU g?1, respectively). The pH, acidity and soluble solids were not affected by probiotic culture and the incorporation technique; however, the VI affected the firmness of fruit. The MPM was within Brazilian standards for their microbiological characteristics. MPM may be used as a carrier of probiotic bacteria, being one more alternative for individuals who consume probiotic products. 相似文献
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Signatures of a Two‐Dimensional Ferromagnetic Electron Gas at the La0.7Sr0.3MnO3/SrTiO3 Interface Arising From Orbital Reconstruction 下载免费PDF全文
67.
Thomas Huld Marcel úri Ewan D. Dunlop 《Progress in Photovoltaics: Research and Applications》2008,16(7):595-607
We present a geographical assessment of the performance of crystalline silicon photovoltaic (PV) modules over Europe. We have developed a method that is based on a material specific analytical expression of the PV conversion efficiency, relative to nominal efficiency, as a function of module temperature and irradiance. This method is combined with a climate database that includes average daytime temperature and irradiance profiles. It is found that the geographical variation in ambient temperature and yearly irradiation causes a decrease in overall yearly PV performance from 3 to 13% relative to the performance under Standard Test Conditions, with the highest decrease found in the Mediterranean region. Based on the above results we developed a simplified linear expression of the relative PV module efficiency that is a simple function of yearly total irradiation and yearly average daytime temperature. The coefficients to the linear expression are found by fitting to the map resulting from the above‐mentioned analytical approach. The prediction of total yearly PV output from this linear fit deviates less than 0·5% from the more detailed calculation, thus providing a faster and more simplified alternative to the yield estimate, in the case when only limited climate data are available. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
68.
Yuriy Zakrevskyy Marcel Richter Svitlana Zakrevska Nino Lomadze Regine von Klitzing Svetlana Santer 《Advanced functional materials》2012,22(23):5000-5009
The light‐induced reversible switching of the swelling of microgel particles triggered by photo‐isomerization and binding/unbinding of a photosensitive azobenzene‐containing surfactant is reported. The interactions between the microgel (N‐isopropylacrylamide, co‐monomer: allyl acetic acid, crosslinker: N,N′‐methylenebisacrylamide) and the surfactant are studied by UV‐Vis spectroscopy, dynamic and electrophoretic light scattering measurements. Addition of the surfactant above a critical concentration leads to contraction/collapse of the microgel. UV light irradiation results in trans‐cis isomerization of the azobenzene unit incorporated into the surfactant tail and causes an unbinding of the more hydrophilic cis isomer from the microgel and its reversible swelling. The reversible contraction can be realized by blue light irradiation that transfers the surfactant back to the more hydrophobic trans conformation, in which it binds to the microgel. The phase diagram of the surfactant‐microgel interaction and transitions (aggregation, contraction, and precipitation) is constructed and allows prediction of changes in the system when the concentration of one or both components is varied. Remote and reversible switching between different states can be realized by either UV or visible light irradiation. 相似文献
69.
Aguor EN Arslan F van de Kolk CW Nederhoff MG Doevendans PA van Echteld CJ Pasterkamp G Strijkers GJ 《Magma (New York, N.Y.)》2012,25(5):369-379
Object
Imaging of myocardial infarct composition is essential to assess efficacy of emerging therapeutics. T 2 * mapping has the potential to image myocardial hemorrhage and fibrosis by virtue of its short T 2 * . We aimed to quantify T 2 * in acute and chronic myocardial ischemia/reperfusion (I/R) injury in mice.Materials and methods
I/R-injury was induced in C57BL/6 mice (n?=?9). Sham-operated mice (n?=?8) served as controls. MRI was performed at baseline, and 1, 7 and 28?days after surgery. MRI at 9.4?T consisted of Cine, T 2 * mapping and late-gadolinium-enhancement (LGE). Mice (n?=?6) were histologically assessed for hemorrhage and collagen in the fibrotic scar.Results
Baseline T 2 * values were 17.1?±?2.0?ms. At day 1, LGE displayed a homogeneous infarct enhancement. T 2 * in infarct (12.0?±?1.1?ms) and remote myocardium (13.9?±?0.8?ms) was lower than at baseline. On days 7 and 28, LGE was heterogeneous. T 2 * in the infarct decreased to 7.9?±?0.7 and 6.4?±?0.7?ms, whereas T 2 * values in the remote myocardium were 14.2?±?1.1 and 15.6?±?1.0?ms. Histology revealed deposition of iron and collagen in parallel with decreased T 2 * .Conclusion
T 2 * values are dynamic during infarct development and decrease significantly during scar maturation. In the acute phase, T 2 * values in infarcted myocardium differ significantly from those in the chronic phase. T 2 * mapping was able to confirm the presence of a chronic infarction in cases where LGE was inconclusive. Hence, T 2 * may be used to discriminate between acute and chronic infarctions. 相似文献70.