共查询到20条相似文献,搜索用时 78 毫秒
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简单介绍了聚醚醚酮(PEEK)的基本结构与特性。详细综述了几种改善聚醚醚酮植入材料抗菌性的方法及其相应的改性机理,包括化学改性、负载改性、涂层改性、辐照改性、陶瓷共混改性等。其中,涂层改性包括氧化石墨烯、黑磷等生物活性涂层改性,辐照改性又可分为等离子处理、微波辐照等改性措施。最后对聚醚醚酮在医学领域的应用进行了展望,并提出其在抗菌方面依然存在的问题与挑战。 相似文献
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无机纳米粒子在环氧树脂增韧改性中的应用 总被引:8,自引:0,他引:8
无机纳米粒子能够给聚合物赋以卓越的综合性能,为此,纳米材料在聚合物改性中的应用已成为聚合物改性领域中的一个研究热点。本文就近年来在环氧树脂增韧改性中应用的无机纳米粒子的种类、环氧树脂/无机纳米复合材料的制备方法及其应用研究进展进行了综述。 相似文献
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木质素活化改性制备酚醛树脂胶黏剂研究进展 总被引:1,自引:0,他引:1
木质素由于化学结构与苯酚相似,通过活化改性可部分替代苯酚制备木质素改性酚醛树脂胶黏剂。既可降低成本、达到生物质资源高效利用的目的,并且制备的木质素改性酚醛树脂胶黏剂有毒残余较低,具有环保意义,是合成制备生物质高分子材料的重要途径。本文综述了国内外研究人员在木质素活化改性制备酚醛树脂胶黏剂研究领域的最新进展,重点介绍了化学改性、物理改性、生物改性等木质素活化改性方法,比较了不同改性产物制备酚醛树脂胶黏剂的性能,并对影响木质素活化改性制备酚醛树脂胶黏剂实现工业化应用的主要因素进行了分析。 相似文献
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Herrmann A 《Angewandte Chemie (International ed. in English)》2007,46(31):5836-5863
Volatile organic compounds serve in nature as semiochemicals for communication between species, and are often used as flavors and fragrances in our everyday life. The quite limited longevity of olfactive perception has led to the development of pro-perfumes or pro-fragrances--ideally nonvolatile and odorless fragrance precursors which release the active volatiles by bond cleavage. Only a limited amount of reaction conditions, such as hydrolysis, temperature changes, as well as the action of light, oxygen, enzymes, or microorganisms, can be used to liberate the many different chemical functionalities. This Review describes the controlled chemical release of fragrances and discusses additional challenges such as precursor stability during product storage as well as some aspects concerning toxicity and biodegradability. As the same systems can be applied in different areas of research, the scope of this Review covers fragrance delivery as well as the controlled release of volatiles in general. 相似文献
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Kirschning A Solodenko W Mennecke K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(23):5972-5990
The concepts article describes enabling techniques (solid-phase assisted synthesis, new reactor design, microwave irradiation and new solvents) in organic chemistry and emphasizes the combination of several of them for creating new synthetic technology platforms. Particular focus is put on the combination of immobilized catalysts as well as biocatalysts with continuous flow processes. In this context, the PASSflow continuous flow technique fulfils both chemical as well as chemical engineering requirements. It combines reactor design with optimized, monolithic solid phases as well as reversible immobilization techniques for performing small as well as large scale synthesis with heterogenized catalysts under continuous flow conditions. 相似文献
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《印度化学会志》2023,100(1):100818
In the present paper, the heat generating and/or absorption as well as thermo-diffusion on the unsteady free convection MHD gyrating flow of radiation and chemical reactive second grade fluid past an unbounded perpendicular plate during absorbent medium have been discussed. Here, it is assumed that, the confining plate has the ramped wall temperature with ramped surface concentration and isothermal temperature with ramped surface concentration. The analytical solutions for the governing equations are found by utilization of Laplace transformation methodology. The velocity, temperature and concentration profiles are analyzed with quite few figures. It is determined that, velocity, temperature and concentration distribution sketches in case of ramped temperature as well as ramped surface concentration are not as much of as those of isothermal temperature as well as ramped surface concentration. In addition to the idioms of skin friction, Nusselt number as well as Sherwood number are achieved and characterized numerically with tabular format. 相似文献
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Enzyme-based biocatalysis is emerging as an advanced technique to develop green processes that help to maintain the sustainability of the environment. The bioremediation of toxic organic pollutants and waste to bioenergy production using enzymes as biocatalysts is rapidly growing due to its eco-friendly and sustainable nature. Additionally, a range of microbial species that typically grow on organic wastes can be used to produce these enzymes in an efficient manner. This is seen as a potential strategy for the development of cost-effective manufacturing for a number of biotechnological applications. The present study discusses biocatalysis as a promising and sustainable method toward the bioremediation of hazardous organic pollutants as well as for bioenergy production, based on the immense potential of enzymes as biocatalysts. Emphasis has been placed on evaluating the critical elements that can enhance the production of enzymes used as biocatalysts, as well as their functional effectiveness and stability. 相似文献
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The utility of diphosphorous tetraiodide as a new, mild, condensing agent for synthesis of oxadiazole is described. These data indicate the simple dehydration of oximes to 1,2,5-oxadiazole as well as the rearrangements of oximes to normal Beckmann product 1,2,4-oxadiazole. However, mono-oxime of benzil undergoes abnormal Beckman rearrangement to benzaldehyde as major product. The described method is simple and important for the synthesis of the oxadiazoles as well as for nitriles. 相似文献
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A general overview of the development of the uses of light-emitting diodes in analytical instrumentation is given. Fundamental aspects of light-emitting diodes, as far as relevant for this usage, are covered in the first part. The measurement of light intensity is also discussed, as this is an essential part of any device based on light-emitting diodes as well. In the second part, applications are discussed, which cover liquid and gas-phase absorbance measurements, flow-through detectors for chromatography and capillary electrophoresis, sensors, as well as some less often reported methods such as photoacoustic spectroscopy. 相似文献
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Aptamers: molecular tools for analytical applications 总被引:3,自引:0,他引:3
Mairal T Ozalp VC Lozano Sánchez P Mir M Katakis I O'Sullivan CK 《Analytical and bioanalytical chemistry》2008,390(4):989-1007
Aptamers are artificial nucleic acid ligands, specifically generated against certain targets, such as amino acids, drugs,
proteins or other molecules. In nature they exist as a nucleic acid based genetic regulatory element called a riboswitch.
For generation of artificial ligands, they are isolated from combinatorial libraries of synthetic nucleic acid by exponential
enrichment, via an in vitro iterative process of adsorption, recovery and reamplification known as systematic evolution of
ligands by exponential enrichment (SELEX). Thanks to their unique characteristics and chemical structure, aptamers offer themselves
as ideal candidates for use in analytical devices and techniques. Recent progress in the aptamer selection and incorporation
of aptamers into molecular beacon structures will ensure the application of aptamers for functional and quantitative proteomics
and high-throughput screening for drug discovery, as well as in various analytical applications. The properties of aptamers
as well as recent developments in improved, time-efficient methods for their selection and stabilization are outlined. The
use of these powerful molecular tools for analysis and the advantages they offer over existing affinity biocomponents are
discussed. Finally the evolving use of aptamers in specific analytical applications such as chromatography, ELISA-type assays,
biosensors and affinity PCR as well as current avenues of research and future perspectives conclude this review. 相似文献
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Asymmetric multicomponent reactions involve the preparation of chiral compounds by the reaction of three or more reagents added simultaneously. This kind of addition and reaction has some advantages over classic divergent reaction strategies, such as lower costs, time, and energy, as well as environmentally friendlier aspects. All these advantages, together with the high level of stereoselectivity attained in some of these reactions, will force chemists in industry as in academia to adopt this new strategy of synthesis, or at least to consider it as a viable option. The positive aspects as well as the drawbacks of this strategy are discussed in this Review. 相似文献