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991.
随着环境污染与能源危机的问题日益严重,利用清洁能源太阳能的光催化技术得到了研究者的广泛关注.然而,半导体光催化剂的带隙严重限制了其利用整个太阳光谱的能力.尽管通过能带工程、上转换等技术,已经有部分可见光可以被利用,但其本身的效率却并不高.太阳光谱中的近红外光有着显著的光热效应,可提高光催化反应的温度,促进光生载流子的分离,进而提升光催化的效果.光子晶体是一种周期性结构,通过调节其折射率以及孔径大小,可以对不同波段的光实现增强吸收或反射的效果.人们已制备了二氧化钛的反蛋白石结构用于光催化降解污染物,其光催化效率明显提高.但是,通过利用反蛋白石结构光子晶体增强近红外光的吸收,进而实现全光谱利用的光热协同催化目前还未有报道.本文以二氧化硅单分散微球为模板,制备了以苯胺黑-聚偏氟乙烯为基底、氧化锌为光催化剂的反蛋白石结构光子晶体薄膜,采用扫描电镜、XRD和XPS等技术表征了薄膜的结构,并通过透射光谱与镜面反射光谱验证了苯胺黑的加入可增强全光谱的利用率.结果发现,当苯胺黑掺量为0.5%时,微反应器中的薄膜温度在60 min内上升了13.6℃,而空气中的薄膜温度在2 min内升了24.5℃,表明苯胺黑在近红外光生热中起着重要作用.对比普通薄膜,Z0.5A-369在微反应器与空气中的温度分别提升了14.7和26.8℃,证实了光子晶体对于光谱吸收的增强效应.就光催化性能来看,Z0.5A-369比普通薄膜的效率提高了1.63倍,而微反应器也比普通反应器提升了5.85倍.可见,薄膜和反应器的设计实现了协同催化.光热协同光催化发现,利用近红外光的光热效应来提高光催化反应过程中的温度可有效促进光催化反应,是一种高效利用太阳光谱的方法.光子晶体因其多孔结构、高比表面积、限光效应和慢光效应而增强了对光的吸收,进一步提高了光催化效率.另外,微反应器通过其局域的热效应和缩短的传质路径有效地增加了反应速率. 相似文献
992.
Zhang Xie Zheng Li Gang Lou Qing Liang Jiang-Xing Chen Jianlong Kou Gui-Na Wei 《理论物理通讯》2021,73(5):55602
The folding and unfolding of the carbon chain, which is the basic constitutional unit of polymers,are important to the performance of the material. However, it is difficult to regulate conformational transition of the carbon chain, especially in an aqueous environment. In this paper, we propose a strategy to regulate the conformational transition of the carbon chain in water based on the all-atom molecular dynamics simulations. It is shown that the unfolded carbon chain will spontaneously collapse into the folded state, while the folded carbon chain will unfold with an external electric field. The regulation ability of the electric field is attributed to the electric field-induced redistribution of interface water molecules near the carbon chain. The demonstrated method of regulating conformational transition of the carbon chain in water in this study provides an insight into regulating hydrophobic molecules in water, and has great potential in drug molecule design and new polymer material development. 相似文献
993.
寇政文 《曲靖师范学院学报》2011,30(2):1-5
目前,朱德建党思想研究多从廉政视角展开,而将其作为独立研究领域进行宏观考察的相对较少,尚需深挖和进行理论规整。朱德作为老一辈无产阶级政党领袖,在革命、建设中对党的建设进行了许多深入思考,有着特色的表述方式:站在"科学最高成就"的高度认识马克主义理论指导地位,倡导理论学习与指导的"一贯性"与"发展性";以"站在群众之中"的政党建设根本利益观作为尺度,倡导党的群众利益观;把发展作为恒久命题,倡导党应领导建立"革命家务"和搞好建设;把干部发展作为主线,倡导人才选拔"眼光向下"、青年成长重在学习。 相似文献
994.
研究了1维简单晶格振动热容,得到了热容的表达式,并讨论了高温、低温情况,得到了在低温极限情况下,1维简单晶格振动热容与温度成正比的研究结果. 相似文献
995.
Min Chao Kaichang Kou Guanglei Wu Jiaoqiang Zhang Ning Li Dongna Zhang 《Journal of Macromolecular Science: Physics》2013,52(10):2003-2014
Copolyimides were prepared from 4,4′-diaminodiphenylether (4,4′-ODA), 1,3-bis(4-aminophenoxy) benzene (TPER), and pyromellitic dianhydride (PMDA) through a three-step imidization process with different monomer compositions. The copolymerization disrupted the molecular regularity and decreased the intermolecular interaction of the polyimide chains. The X-ray diffraction (XRD) results indicated the prepared copolyimides showed the same semicrystalline character, but had various crystallinity and crystal forms. The copolymerization also changed the crystal morphologies of the polyimides. With increasing TPER ratio, the copolyimides started to form spherulites and hedrites, which then tended to grow more perfectly as the TPER ratio was further increased. The solubility of the copolyimides and their dependence on the crystallnity and the chain flexibility was investigated. These copolyimides exhibited excellent thermal and thermo-oxidative stability. 相似文献
996.
997.
Shu Wang Xudong Zhang Jiangong Li Qiang Tian Xinli Kou 《Applied Physics A: Materials Science & Processing》2011,104(1):415-423
The effect of B content on the structure, soft magnetic properties, and high frequency characteristics of as-deposited FeCoB-Al2O3 nanogranular films fabricated by radio frequency magnetron co-sputtering was studied in this work. The introduction of B into the FeCo-Al2O3 films leads to a refinement of granular microstructure. The FeCoB-Al2O3 nanogranular films consist of the FeCoB nanoparticles uniformly embedded in the amorphous Al2O3 matrix. An addition of a small amount of B into the FeCo-Al2O3 films can markedly decrease the coercivity of the films. The excellent magnetic softness with a low coercivity of about 0.08?kA/m was achieved in the FeCoB-Al2O3 films. The Henkel plots confirm the existence of intergranular exchange coupling in the FeCoB-Al2O3 films. The FeCoB-Al2O3 films with low B content exhibit a high permeability over 200 at low frequency and a high-resonance frequency of 3.2?GHz, implying a high cut-off frequency for high frequency applications. 相似文献
998.
999.
Perhexiline is an effective drug for angina pectoris, but prolong use of the drug may induce toxicity. A simple and sensitive method was developed for monitoring the drug to avoid over medication. The method is based on derivatizing perhexiline with a fluorescent reagent (2‐napththoxy) acetyl chloride. The resulting derivative is highly responsive to a fluorimetric detector (λex = 230 nm, λem = 347 nm). The lower quantitation limit of the method is attainable at 0.3 μM with a detection limit of about 30 nM (S/N = 3 with 10 μL injected). The method was applicable to the analysis of perhexiline in spiked plasma. 相似文献
1000.
Fluorescence in situ Hybridization (FISH) was used to investigate whether the chromosome of the fetus prenatally diagnosed as pyelectasis was normal or not. Amniotic fluid was taken from the pregnant woman whose fetus was detected with pyelectasia by prenatal examination. The chromosome of the amniotic fluid cell without culture was examined with FISH. The result shows that compared with the traditional amniotic fluid cell culture, FISH has the advantages of more rapid, higher sensitivity and specificity, and was 10-12 days earlier to complete the diagnosing than the traditional method. The fetuses detected chromosomal abnormality in each groups were induced during the middle and late trimester, while those fetuses with normal chromosome continued pregnancy, the rate of spontaneous disappearance of pyelectasia decreased as the severity of pyelectasia increased. FISH can satisfy the urgent need in the clinical prenatal diagnosis due to its rapidity to determine whether fetus with pyelectasia was accompanied with chromosomal. 相似文献