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971.
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Marlene Knausz Gernot Oreski Gabriele C. Eder Yuliya Voronko Bernadette Duscher Thomas Koch Gerald Pinter Karl A. Berger 《应用聚合物科学杂志》2015,132(24)
In reliability testing of components for PV modules an always remaining question is about material (in)compatibilities and synergistic effects and thus, how results of singly tested materials correlate with materials aged within PV modules. Testing of single materials would simplify sample preparation, reduce costs and offer more testing options. Therefore the main objective of this study was to compare the aging behavior of single backsheets with that of backsheets incorporated within PV modules. Four different types of backsheets were chosen, all of them comprising of polyethylene terephthalate (PET) core layers, but differing outer protection layers. Test modules using identical components, varying only in the type of backsheet used were produced and damp heat aged (85°C/85% RH ≤2000 h). The results revealed no influence of the PV module lamination on the thermal characteristics of the polymeric backsheets. Even after DH aging, differences between single and module laminated backsheets were negligible. Degradation effects of PET could be detected for all aged sheets by thermal analysis and were confirmed by tensile tests and rheological measurements. Thus, it can be stated that testing of single PET based backsheets under DH aging conditions is a practicable way to investigate the applicability of a new backsheet. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42093. 相似文献
975.
Manfred A. Bohn Moritz Heil Heike Pontius Ernst-Christian Koch 《Propellants, Explosives, Pyrotechnics》2024,49(2):e202300055
Two compatibility test types based on gas generation obtained by vacuum stability test (VST) procedure and on heat generation obtained by heat flow microcalorimetry (HFMC) show that nitroguanidine (NGu), CAS-No. [556-88-7], is compatible with ammonium nitrate (AN), CAS-No. [6484-52-2], ammonium dinitramide (ADN), CAS-No. [140456-78-6], 1,1-diamino-dinitroethylene (FOX-7, DADNE), CAS-No. [145250-81-3], N-guanylurea dinitramide (FOX-12, GUDN, carbamoylguanidinium dinitramide), CAS-No. [217464-38-5], hexogen (RDX), CAS-No. [121-82-4], octogen (HMX), CAS-No. [2691-41-0], and trinitrotoluene (TNT), CAS-No. [118-96-7]. The evaluations with gas generation and heat generation were done using the so-called corresponding reactivity quantities RV and RQ, but the assessment criteria are in accordance with the present NATO standards. NGu and ADN show the rare case of reactivity with a negative assessment quantity, that is their inter-component reactivity quantities show negative values in RV and RQ. The evolved gas volume and the produced heat generation of the 1 : 1 mixture have lower values than the formally calculated values of the mixture. The root cause of this cannot be deduced with mere compatibility testing. A negative assessment quantity RQ is also observed with NGu and TNT at 80 °C, but not at 70 °C. 相似文献
976.
977.
Peter Kuper Werner-Michael Kulicke Stefan Horner Bodo Saake Jürgen Puls Jürgen Kunze Hans-Peter Fink Ute Heinze Thomas Heinze Erik-Andreas Klohr Heiko Thielking Wolfgang Koch 《大分子材料与工程》1998,260(1):53-63
Sodium carboxymethylcellulose (NaCMC) with varying degrees of substitution (DS) was investigated with different analytical methods in order to characterize the functional group distribution. The following methods were tested and adapted: high-resolution 13C NMR spectroscopy in the solid state (13C CP/MAS NMR) and 13C NMR spectroscopy on solutions of NaCMC samples with a reduced molar mass. Partial degradation was accomplished by ultrasonic means and with the enzyme endoglucanase. Combining the two techniques resulted in the greatest reduction in molar mass and hence in the best spectral resolution. Analysis of the NaCMC fragments following ultrasonic and/or endoglucanase degradation also reveals another interesting experimental finding. It appears that ultrasonic degradation is favored at unsubstituted areas near the center of the chain. These methods were compared with the following already familiar techniques of analysis: titrimetric techniques; 13C and 1H NMR spectroscopy as well as HPLC on completely hydrolysed solutions (hydrolysis with perchloric acid, trifluoroacetic acid and sulfuric acid). All of the methods characterize the samples as a series with increasing DS, the values of which range from 0.9 to 2.4. Methods that permit analysis of the partial degree of substitution produced the distribution x2 > x6 > x3. Therefore, they are in principle suited for determining the functionalization pattern of the NaCMC samples relative to one another. The most suitable method can therefore be selected according to the objectives and the apparatus available. However, the measured values do exhibit considerable spread, variances of approx. 20%, thus, place restrictions on using the values of DS or xi in absolute comparisons beyond these methods. 相似文献
978.
979.
980.
Jan Olav Jensen Dagfinn Sagen Helge Lunder Torstein Koc Thomas Knigge Sigrid Moldestad 《世界建筑导报》2011,26(3):70-71
河边桑拿位于一条美丽的河边,可以全景观赏远山的景色。它建在菲多斯景观酒店附近,供酒店的客人使用。桑拿房有一面玻璃墙,朝向景区。建筑物建在地形中,除玻璃墙外,四周用青草覆盖。 相似文献