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991.
在介绍国内汽车涂装的环保、节能减排现状及差距和"绿色涂装"理念(6个高效、10个更少、2个高效、1个更低)的基础上,按汽车涂装工艺推荐了26项成熟的先进适用的绿色涂装工艺技术。 相似文献
992.
993.
利用分光光度法比较了3种显色体系——酸性铬蓝K、铬黑T、酸性铬蓝K-萘酚绿B在测定钙镁离子浓度时所需试验条件的差异。结果表明:利用酸性铬蓝K-萘酚绿B混合溶液作为显色剂时,所得钙镁离子浓度标准曲线拟合度好,结果准确。 相似文献
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995.
Nanographitic materials are gaining enormous interest as a new class of reinforcement for nanocomposites, promising revolutionary electrical, thermal, and mechanical properties. However, the progress has been quite limited especially in terms of mechanical properties. Here we report a significant leap, >2× increases in tensile strength and modulus of an epoxy composite using surface treated graphite nanoplatelets (GnPs). This corroborated by increases in Tgs as well as the presence of oxygen‐functionalized groups verified by XPS, suggest improved distribution and chemical interaction at the filler‐to‐matrix interface. Toughness values also showed increases with concentration, without compromising the strength or failure strain. However, if solvent levels during degassing were not reduced sufficiently, negligible contributions to strength and stiffness were observed with GnP loading. Subsequent elevated temperature treatments increased the strength of the composite due to cure enhancement of the matrix material, yet did not provide mechanical enhancements due to the incorporation of the filler. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40802. 相似文献
996.
Elaboration of small‐diameter vascular prostheses—Selection of appropriate sterilisation method 下载免费PDF全文
Olga Chrzanowska Marcin Henryk Struszczyk Izabella Krucinska Michał Puchalski Lucyna Herczyńska Michał Chrzanowski 《应用聚合物科学杂志》2014,131(18)
The aim of study is the elaboration of semi‐biodegradable, multilayered tubular structures as substitutes for the reconstruction of small diameter vascular prostheses (<6 mm). The inert external layer of the prostheses will be fabricated via the melt electrospinning of poly (l ‐lactide‐co‐glycolide) (PLGA). The middle layer will be constructed from polypropylene (PP); the first prototype will be produced via melt electrospinning and the second using the melt blowing technique. The general aim of this stage of the research is the selection of a sterilisation technique that is appropriate for semi‐biodegradable, multilayered tubular structures. For this purpose, single tubular structures created via the melt electrospinning of PLGA or PP and melt blown tubular structures of PP were elaborated. The influence of steam, ethylene‐oxide (EO), and radiation sterilisation techniques on the elaborated microstructure of tubular structures was analyzed during this study. The effect of each sterilisation technique was evaluated using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy/energy‐dispersive X‐ray spectroscopy analysis (SEM/EDS). The changes in average molecular weight (Mw) and crystallinity index (CI) of the PLGA tubular structures after EO and steam sterilisation were evaluated. The EO and steam sterilisation resulted in the complete destruction of PLGA tubular structures. Only the radiation sterilisation (accelerated electrons) did not influence on PLGA tubular structures morphology as well as thermal and chemical properties. FTIR and SEM/EDS analysis indicated that no changes in the chemical properties of PP tubular structures after each sterilisation occurred. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40812. 相似文献
997.
Dendrimers are novel three dimensional, hyperbranched globular nanopolymeric architectures. Attractive features like nanoscopic size, narrow polydispersity index, excellent control over molecular structure, availability of multiple functional groups at the periphery and cavities in the interior distinguish them amongst the available polymers. Applications of dendrimers in a large variety of fields have been explored. Drug delivery scientists are especially enthusiastic about possible utility of dendrimers as drug delivery tool. Terminal functionalities provide a platform for conjugation of the drug and targeting moieties. In addition, these peripheral functional groups can be employed to tailor-make the properties of dendrimers, enhancing their versatility. The present review highlights the contribution of dendrimers in the field of nanotechnology with intent to aid the researchers in exploring dendrimers in the field of drug delivery. 相似文献
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999.
《Journal of the European Ceramic Society》2014,34(1):81-89
Thermally induced phase separation (TIPS) was used to produce spherical polypropylene–zirconia composite powder for selective laser sintering (SLS). The influence of the composition of the composite starting powder and the SLS parameters on the density and strength of the composite SLS parts was investigated, allowing realizing SLS parts with a relative density of 36%. Pressure infiltration (PI) and warm isostatic pressing (WIPing) were applied to increase the green density of the ZrO2–PP SLSed parts. Infiltrating the SLS parts with an aqueous 30 vol.% ZrO2 suspension allowed to increase the sintered density from 32 to 54%. WIPing (135 °C and 64 MPa) of the SLS and SLS/infiltrated complex shape green polymer–ceramic composite parts prior to debinding and sintering allowed raising the sintered density of the 3 mol Y2O3 stabilized ZrO2 parts to 92 and 85%, respectively. 相似文献
1000.
重金属铬对人类的影响不仅仅只是自身,还会影响以后的一代人甚至是几代人。文章在遵循以废治废及可持续发展的绿色环保理念的前提下,通过粉煤灰净水法与人工复合生态系统净水法的有机结合,使电镀铬废水达标排放。 相似文献