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Solar steam generation has attracted considerable interest due to its easy accessibility and sustainability. However, dye molecules were gradually concentrated on bulk water or the surface of solar absorbers during the disposal of dye wastewater. Herein, LaB6/g-C3N4 composites were immobilized on porous cotton cloth, served as a solar absorber resistant to dye clogging. The optimal solar absorber possessed solar harvesting of 92.3% and showed great application potential in the field of the treatment of dye wastewater. This study presented a new approach for the treatment of dye wastewater.  相似文献   
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Several results based on the Langmuir probes' data on the HL-2A tokamak are presented. The blob structures' radial and poloidal drift velocities, estimated by the gradient of floating potential and by time delay evaluation, are compared in different line-averaged density and electron cyclotron resonance heating conditions. A positive correlation is observed in the comparison between blobs' radial velocity estimated by the two methods mentioned above, regardless of the situation differences mentioned above. Correlation is also observed in the comparison between the blobs' poloidal velocity estimated by the two methods in different situations, while a shift due to the different line-averaged density is observed. These results imply that the radial gradient of floating potential may have some value as a reference during data analysis in low-parameter discharge.  相似文献   
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通过对煤焦油加氢装置能量进行梯级利用,优化能源的使用状态,保证温位的合理匹配,实现降本增效,同时消除装置运行瓶颈问题,提高装置加工负荷,优化设备运行,进而提高煤焦油加氢装置的市场竞争力.  相似文献   
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针对伊拉克米桑油田盐膏层巨厚、钻井液密度窗口窄、存在高压盐水层,储层段漏塌同层导致复杂时效高等问题,通过对比分析国内外盐膏层和窄压力窗口地层钻井技术,总结了米桑油田钻井面临的主要技术难点,从井身结构优化、钻井提速和复杂预防等方面入手,研究形成了适合米桑油田的钻井关键技术,并进行了现场试验应用,取得了显著的效果.伊拉克米桑油田钻井关键技术对该地区钻井技术方案设计和钻井提速提效具有较强的借鉴和指导作用.  相似文献   
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聚氨酯材料在生产生活中应用非常广泛,以其优异的性能被用于各个领域.但废旧的聚氨酯原料有剧毒,难以合理回收,易造成环境污染,限制了聚氨酯在诸多方面的应用,而以生物基为原材料生产可降解聚氨酯,绿色环保,对环境非常友好.综述了国内外可降解聚醚酯型聚氨酯改性的几种方法,同时展望了可降解聚酯性聚氨酯研究的发展趋势.  相似文献   
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Developing high-performance visible-to-UV photon upconversion systems based on triplet–triplet annihilation photon upconversion (TTA-UC) is highly desired, as it provides a potential approach for UV light-induced photosynthesis and photocatalysis. However, the quantum yield and spectral range of visible-to-UV TTA-UC based on nanocrystals (NCs) are still far from satisfactory. Here, three different sized CdS NCs are systematically investigated with triplet energy transfer to four mediators and four annihilators, thus substantially expanding the available materials for visible-to-UV TTA-UC. By improving the quality of CdS NCs, introducing the mediator via a direct mixing fashion, and matching the energy levels, a high TTA-UC quantum yield of 10.4% (out of a 50% maximum) is achieved in one case, which represents a record performance in TTA-UC based on NCs without doping. In another case, TTA-UC photons approaching 4 eV are observed, which is on par with the highest energies observed in optimized organic systems. Importantly, the in-depth investigation reveals that the direct mixing approach to introduce the mediator is a key factor that leads to close to unity efficiencies of triplet energy transfer, which ultimately governs the performance of NC-based TTA-UC systems. These findings provide guidelines for the design of high-performance TTA-UC systems toward solar energy harvesting.  相似文献   
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介绍了高分子材料导热性能影响因素研究进展,重点阐释了聚合物基体的结构特性(链结构、分子间相互作用、取向、结晶度等)、导热填料(种类、含量、形态、尺寸等)以及制备方法等对高分子材料导热性能的影响。  相似文献   
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Mg-Zn-Nd alloy is a promising biodegradable metal material for surgical staples during the reconstruc-tion of digestive tract due to its good biocompatibility and suitable mechanical properties.However,its deformation property and corrosion resistance should be improved to make better safety and effective-ness of staples.In the present study,bi-direction drawing was adopted to maintain the initial texture characteristics,and improve mechanical property and corrosion resistance of Mg-2Zn-0.5Nd alloy.The results showed that the microstructure after bi-direction did not change too much,but the texture could maintain its initial characteristics.The ductility of the alloy with 60 % accumulative area reduction after bi-direction drawing was increased by 70 %,indicating that an outstanding deformation property of Mg-Zn-Nd alloy can be obtained by bi-direction drawing.The corrosion resistance was also improved after bi-direction drawing compared with that under single direction drawing.  相似文献   
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