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101.
Past and Present of Sol-Gel Science and Technology   总被引:17,自引:0,他引:17  
In the last twenty years sol-gel science has undergone a spectacular development. The various stages of the sol-gel process have been scrutinised in considerable detail and a sound basis for future technological developments established. In the beginning the studies centred mainly on silica and silicate glasses and were progressively extended to many ceramics and composites. A turning point was reached with the emergence of ormosils and of organic-inorganic nanocomposites. This opened the gateway to whole classes of new materials. The present studies show a definite tendency towards very specialised high-tech applications.  相似文献   
102.
A photoelectrochemical cell with a coupled SnO2|CdSe nanocrystalline semiconductor electrode has been prepared by sequential deposition of SnO2 and CdSe films onto an optically transparent electrode (OTE), and its photoelectrochemical behavior has been studied. The results show that the coupling of CdSe with SnO2 leads to an improvement in the performance of OTE|SnO2|CdSe over OTE|CdSe cells in terms of increased incident photon-to-current conversion efficiency, increased stability and smaller reversal of current. The favorable positioning of the energy bands of SnO2 and CdSe is responsible for the above observations. Various photoelectrochemical parameters of the OTE|SnO2|CdSe cell obtained for an incident light power of 0.31 mW cm−2 at 470nm, are as follows: Isc ≈ 25–30 μA cm−2, Voc ≈ 0.5–0.6 V, ƒƒ = 0.47 and a power conversion efficiency of about 2.25%.  相似文献   
103.
色谱是一门以分离分析为主,旨在追求复杂事物纯而净的分析化学的重要分支学科.其经过百余年的发展,理论与技术日臻完善,集科学、技术与艺术于一体.近年来,色谱及其与质谱、核磁共振波谱、原子发射光谱等联用技术极大推动了环境、食品、石油化工、生物医药等领域中所涉及复杂体系的研究进展.作为我国传统文化的核心代表,中医药为中国乃至世...  相似文献   
104.
《Mendeleev Communications》2021,31(5):593-604
In this focus overview, the main types and directions of engineering, methods and techniques of intensification of chemical process systems (CPS) and process optimization of energy- and resource-efficient processes for the representative production of titanium compounds, mining waste processing systems, electrochemical coating technologies, combined technologies for the treatment of industrial effluents and energy-and resource-efficient technologies for cleaning soils from petroleum and chemical pollution products are reviewed. The following issues have been discussed: methods of complex assessment of production energy efficiency and software and information support for automated synthesis of optimal energy-efficient regenerative heat exchange systems using pinch analysis; methods and algorithms for fractal-statistical characteristics analysis of nonstationary gas flows in complex gas pipelines; methods of ecological and economic optimization of production, infrastructure supply chains; methods for assessing and preventing the dangerous environmental impact assessment of chemical pollution; organization and logistics management of business processes engineering for improving the energy efficiency of plants; engineering of problem oriented computer systems, heuristic-computational models and algorithms for intelligent integrated logistics support of the equipment life cycle; engineering developments in the field of digital transformation of energy-efficient CPS and technological production systems; application of methods for optimizing reliability factors optimization, digitalized risk and safety management in the engineering of energy- and resource efficient CPS.  相似文献   
105.
如何强化安全工程教育是化学化工类专业高等教育的一个重要课题。通过对蒸汽锅炉爆炸、火灾爆燃事故以及锈蚀危害等3个实例的详细讲述,指出在物理化学的教学中,若适时融入相关的安全工程教育,可以使学生深刻理解安全事故发生及防范所依赖的物理化学原理,从而起到安全意识的内化作用。教学中现代教育技术的引入可以增强这一效果。  相似文献   
106.
Nanomaterials with localized surface plasmon resonance (LSPR) locating in the near-infrared region have broad application prospects in the field of biomedicine. However, the biggest problem that limits the biomedical application of such nanomaterials lies in two aspects: First, the potential long-term in vivo toxicity caused by the metabolism of many nanomaterials with LSPR effect; Second, most of current nanomaterials with LSPR effect are difficult to achieve LSPR wavelength tunability in the near-infrared region to adapt to different biomedical applications. Copper selenide nanomaterials are composed of selenium and copper, which are necessary nutrient elements for human life. Because of the active and flexible chemical properties of selenium and copper, copper selenide nanomaterials can not only be effectively degraded and utilized in human body, but also be endowed with various physicochemical properties by chemical modification or doping. Recently, copper selenide nanomaterials have shown unique properties such as LSPR in the near-infrared region, making them attractive for near-infrared thermal ablation, photoacoustic imaging, disease marker detection, multimode imaging, and so on. Currently, to the best of our knowledge, there is no review on the LSPR properties of copper selenide nanomaterials and its biomedical applications. This review first discusses the relationship between the physicochemical properties and the LSPR of copper selenide nanomaterials and then summarizes the latest progress in the application of copper selenide nanomaterials in biological detection, diagnosis, and treatment of diseases. In addition, the advantages, and prospects of copper selenide nanomaterials in biomedicine are also highlighted.  相似文献   
107.
从过氧化氢(H2O2)的原位生成技术角度总结了近年来利用原位合成H2O2处理水中污染物的研究,分析了当前可充当氢源材料的种类及不同的氢源材料对于提高H2O2产率的影响,以及不同的催化剂材料和催化反应环境提高H2O2利用率对污染处理效果的影响因素,并对原位合成H2O2在水处理领域中面临的挑战和发展前景做了展望,从而为该技术的大规模应用提供指导和借鉴。  相似文献   
108.
W/O型乳胶粒子表面电性的近代测试技术   总被引:1,自引:0,他引:1  
采取近代表面电学测试技术对乳胶粒子表面电性进行微观测量,取得了一系列反映胶粒表面双电层结构的特征参量,证明表面扩散双电层的存在。为完善W/O型乳胶体系的稳定性理论提供了一定实验依据。  相似文献   
109.
In this work, a new hybrid material (C5H6N2Cl)2[FeCl4].Cl abbreviated (CAP)2[FeCl4].Cl was prepared using room temperature slow evaporation technique. The X-ray diffraction analysis revealed that the compound is crystallized in the centrosymmetric space group P21/c of the monoclinic system. The crystallographic network consists of an Fe(III) ion located on an inversion center and coordinated by four chlorine, isolated Cl and two (CAP)+ protonated cations linked by N–H...Cl and C–H...Cl hydrogen bonds to form a zero-dimensional network. Hirshfeld surface analysis was used to analyze intermolecular interactions present in the crystal structure. The vibrational properties were inspected by means of Infra-Red absorption and Raman diffusion spectroscopy techniques. In addition, theoretical calculations based on the DFT/B3LYP/LanL2DZ method and the time-dependent density functional theory (TD–DFT) were performed in order to gain more information and help in the examination of over-all properties of the title compound. Good and interesting experimental findings were presented and good consistency was found with the calculated results.  相似文献   
110.
金鑫  王晓英 《化学学报》2019,77(4):340-350
口腔癌系头颈部癌,癌组织均位于口腔内,其非侵入性早期诊断是减少该病死亡的有效手段.唾液系口腔癌变相关物质首先释放进入的体液,取材方便,安全无创,是口腔癌普查筛选、早期诊断的首选指标.本文对唾液肿瘤生物标志物的种类、目前国内外常用的检测方法进行概述,重点阐述新型电化学生物传感方法在口腔癌相关唾液肿瘤生物标志物检测方面的相关应用及其最新研究进展.并对口腔癌相关唾液肿瘤生物标志物电化学传感技术的未来发展方向提出展望,拟为其深入研究与应用提供参考.  相似文献   
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