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1.
Recently,considerable attention has been paid to the synthesis and research of various rare-earth(RE) doped fluoride nanomaterials because of their high refractive index and appropriate phonon energy,which have potential applications in optics,optoelectronics,microelectronics,and tribology[1].  相似文献   

2.
Recently, low dimension nanostructures have gained considerable attention due to their technological potential as unique types of nanoscale building blocks for future optoelectronic devices and systems. Semiconducting composite nanomaterials, which can combine the advantages of two or more components, have been the focus in the area of nanomaterials synthesis and device application. In this paper, we report our work on the preparation of composite nanomaterials based on CNTs. CNTs were coate…  相似文献   

3.
张新奇 《结构化学》2012,(5):718-722
One-dimensional Nd doped CePO4 hexagonal nanowires have been synthesized for the first time at 140 ℃ for 24 hours via a hydrothermal method using P123 surfactant as the template.The products were characterized by X-ray diffraction,transmission electron microscopy,photoluminescence and high-resolution transmission electron microscopy.Compared with CePO4,one-dimensional nanomaterials we have synthesized,Nd doped CePO4 nanomaterials remain their hexagonal one-dimensional morphology and smooth surface.However,their photoluminescence emissions are greatly enhanced at the wavelength of 348 nm.With their novel fluorescence-emission property,the Nd doped CePO4 nanomaterials are potential in many fields such as optics and electronics.  相似文献   

4.
Organically templated metal phosphates have been extensively studied because of interesting structural chemistry and potential applications in catalysis. However, in most cases the organic templates cannot be removed without collapse of the frameworks. This is in contrast to the high thermal stability and extensive applications of zeolites in refinery and petrochemical processes. Therefore, studies have been directed to the synthesis of transition metal silicates to produce more stable framewo…  相似文献   

5.
LIU Gang  LI De-Hua  ZHANG Ru 《结构化学》2011,30(8):1115-1121
The systematic trends and effect introduced by Zr and C co-doping to TiO2 of electronic structure and optical properties of anatase TiO2 have been calculated by the plane-wave ultra-soft pseudopotential density functional theory (DFT) method within the generalized gradient approximation (GGA) for the exchange-correlation potential. Through the current calculations, the density of states (DOS), energy band structure and optical absorption coefficients have been obtained for TiO2 and compared with the doped TiO2, and the influence of electronic structure and optical properties caused by Zr and C co-doping has been presented qualitatively together. The results revealed that the energy band gap has been decreased owing to the doped Zr and C, whereas the optical absorption coefficients have been increased in the region of 400~800 nm and a red shift of absorption band can be found. Accordingly, photo catalytic activity of TiO2 has been enhanced. The current calculations are in good agreement with the experimental data.  相似文献   

6.
Quantum dots (QDs) have received more and more attention as a novel example of nanomaterials. Due to their unique fluorescent characteristics,quantum dots have been successfully applied in biotech-nology and medicine applications. Recently,the toxicity and the potential environmental effects of QDs have become a research hotspot. In this paper,toxicological effects of QDs are reviewed,and the prospects and research directions are given based on the analysis of this research field.  相似文献   

7.
Poly-3-methylthiophene (P3MT) was synthesized in the room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6) by constant potential and constant current respectively. The structure and morphology of P3MT films were characterized by FTIR spectrum and SEM. The undoped (reduction) and doped (oxidation) forms of P3MT film prepared in ionic liquid were reversible and stable. The P3MT film has strong characteristics of electrocatalytic oxidation of ascorbic acid and can separate the oxidation peaks of ascorbic acid and dopamine. Two methods of potential steps were used to observe the response time of the film and the film was found to have perfect electrochromic response.  相似文献   

8.
Due to the excellent properties including high specificity,low side-effect and good biocompatibility,conjugated polymer nanomaterials have been served as efficient anticancer reagents in die past decades.According to the developed anticancer systems based on conjugated polymer nanomaterials,it could be summarized into three main cancer therapy strategies:photodynamic therapy(PDT),photothermal therapy(PTT)and combination therapy.In this mini review,we provide a brief introduction to three different cancer therapy modes,their mechanisms and potential biological applications.Furthermore,some perspectives on the further development of conjugated polymer nanomaterials are proposed in the territory of anticancer precision medicine.  相似文献   

9.
1 INTRODUCTION The design synthesis of metal oxide heterpoly compounds have been the subject due to their diverse structures and potential applications in catalysis, sorption, electrical conductivity, ion exchange and anti-virus[1]. Molybdenum phosphates with microporous framework serve as a new kind of inorganic microporous materials. In the course of our investigation on the synthesis of Molybdenum phosphates, we have hydrothermally synthesized an organically templated solid material[…  相似文献   

10.
Low-temperature catalytic preparation of multi-wall MoS_2 nanotubes   总被引:1,自引:0,他引:1  
Since the first report on inorganic fullerene-like WS2 polyhedra and nanotubes by Tenne et al.[1] in 1992, this kind of nanostructural materials have become extensive research topics owing to their unique electronic structures. WS2 and MoS2 nanomaterials have shown potential applications in the fields of scanning probe microscopy[2], solid-state lubrication[3], heterogeneous catalysis[4], and electrochemical hydrogen storage[5]. Up to now, a great deal of progress has been achieved in the st…  相似文献   

11.
Phase and structural relationships of the sulfur, selenium, and tellurium compounds of the 4d and 5d transition elements of groups IV to VII of the periodic system are discussed. Homologous elements behave very similarly with respect to the chalcogens, and this is particularly the case for niobium and tantalum, and for molybdenum and tungsten. However, zirconium, niobium, and molybdenum have a greater tendency towards formation of chalcogen-poor phases than their homologues hafnium, tantalum, and tungsten. Subchalcogenides are known only for zirconium and niobium. The number of phases and the tendency towards formation of solid solutions are considerably smaller among the tellurides than among the sulfides and selenides. The crystal structures of the telluride phases also differ from those of the sulfide and selenide phases of analogous composition. In addition, a review of the phase and structural relationships of the arsenic and antimony compounds of the 4d and 5d transition elements of groups V to VII is given.  相似文献   

12.
翟广玉 《化学通报》2021,84(12):1338-1344
芦丁属于类黄酮化合物,广泛存在于人们日常食用的各种蔬菜、水果和中草药中。 芦丁是天然的抗氧化剂,有清除自由基的特性,可调节众多疾病有关的细胞内和细胞外信号通路,影响细胞的生长,分化及其功能,对人们的健康,防病治病起着重要作用。芦丁具有广泛的药理活性,抗氧化、抗炎、抗病毒、抗癌、预防和治疗心脑血管疾病。以芦丁为原料的药品有多种,使用芦丁毒副作用小,安全,成本低。由于芦丁的生物利用度低,在临床上应用受到一定的限制。克服芦丁溶解性差的问题已经有各种方法,例如使用环糊精的络合,磷脂等,改善水溶性,从而增加生物利用度。本文综述了芦丁的多种潜在用途和治疗作用的信息,与药物输送相关的问题,以及改善药物生物利用度的可能方法。重点介绍了芦丁的抗炎、抗癌、降糖、对心血管的保护作用,为天然化合物的开发和利用奠定基础。  相似文献   

13.
There is currently a worldwide consensus and recognition of the undoubted health benefits of the so-called Mediterranean diet, with its intake being associated with a lower risk of mortality. The most important characteristics of this type of diet are based on the consumption of significant amounts of fruit, vegetables, legumes, and nuts, which provide, in addition to some active ingredients, fiber and a proportion of vegetable protein, together with extra virgin olive oil (EVOO) as the main sources of vegetable fat. Fish and meat from poultry and other small farm animals are the main sources of protein. One of the main components, as already mentioned, is EVOO, which is rich in monounsaturated fatty acids and to a lesser extent in polyunsaturated fatty acids. The intake of this type of nutrient also provides an important set of phytochemicals whose health potential is widely spread and agreed upon. These phytochemicals include significant amounts of anthocyanins, stilbenes, flavonoids, phenolic acids, and terpenes of varying complexities. Therefore, the inclusion in the diet of this type of molecules, with a proven healthy effect, provides an unquestionable preventive and/or curative activity on an important group of pathologies related to cardiovascular, infectious, and cancerous diseases, as well as those related to the metabolic syndrome. The aim of this review is therefore to shed light on the nutraceutical role of two of the main phytochemicals present in Olea europaea fruit and leaf extracts, polyphenols, and triterpenes, on healthy animal growth. Their immunomodulatory, anti-infective, antioxidant, anti-aging, and anti-carcinogenic capabilities show them to be potential nutraceuticals, providing healthy growth.  相似文献   

14.
We review the syntheses, optical properties, and biological applications of cadmium selenide (CdSe) and cadmium selenide–zinc sulfide (CdSe–ZnS) quantum dots (QDs) and gold (Au) and silver (Ag) nanoparticles (NPs). Specifically, we selected the syntheses of QDs and Au and Ag NPs in aqueous and organic phases, size- and shape-dependent photoluminescence (PL) of QDs and plasmon of metal NPs, and their bioimaging applications. The PL properties of QDs are discussed with reference to their band gap structure and various electronic transitions, relations of PL and photoactivated PL with surface defects, and blinking of single QDs. Optical properties of Ag and Au NPs are discussed with reference to their size- and shape-dependent surface plasmon bands, electron dynamics and relaxation, and surface-enhanced Raman scattering (SERS). The bioimaging applications are discussed with reference to in vitro and in vivo imaging of live cells, and in vivo imaging of cancers, tumor vasculature, and lymph nodes. Other aspects of the review are in vivo deep tissue imaging, multiphoton excitation, NIR fluorescence and SERS imaging, and toxic effects of NPs and their clearance from the body. Figure Semiconductor quantum dots and metal nanoparticles have extensive applications, e.g., in vitro and in vivo bioimaging Tamitake Itoh and Abdulaziz Anas contributed equally to this article.  相似文献   

15.
The review presents a comprehensive survey of recent developments and applications of high performance capillary and microchip electroseparation methods (zone electrophoresis, isotachophoresis, isoelectric focusing, affinity electrophoresis, electrokinetic chromatography, and electrochromatography) for analysis, micropreparation, and physicochemical and biochemical characterization of peptides since 2017 up to about the middle of 2019. Progress in the study of electromigration properties of peptides and in the methodology of their analysis (sample preseparation, preconcentration and derivatization, adsorption suppression, EOF control, and detection) are described. Advances in CE and CEC methods are demonstrated and their applications in the following areas are presented: qualitative and quantitative analysis, determination in complex (bio)matrices, monitoring of chemical and enzymatical reactions and physical changes, amino acid, sequence and chiral analysis, and peptide mapping of proteins. In addition, micropreparative separations and determinations of important physicochemical characteristics of peptides by CE and CEC methods are reported.  相似文献   

16.
The scale at which MS‐ and NMR‐based platforms generate metabolomics datasets for both research, core, and clinical facilities to address challenges in the various sciences—ranging from biomedical to agricultural—is underappreciated. Thus, metabolomics efforts spanning microbe, environment, plant, animal, and human systems have led to continual and concomitant growth of in silico resources for analysis and interpretation of these datasets. These software tools, resources, and databases drive the field forward to help keep pace with the amount of data being generated and the sophisticated and diverse analytical platforms that are being used to generate these metabolomics datasets. To address challenges in data preprocessing, metabolite annotation, statistical interrogation, visualization, interpretation, and integration, the metabolomics and informatics research community comes up with hundreds of tools every year. The purpose of the present review is to provide a brief and useful summary of more than 95 metabolomics tools, software, and databases that were either developed or significantly improved during 2017–2018. We hope to see this review help readers, developers, and researchers to obtain informed access to these thorough lists of resources for further improvisation, implementation, and application in due course of time.  相似文献   

17.
This review focuses on key topics in the field of drug delivery related to the design of nanocarriers answering the biomedicine criteria, including biocompatibility, biodegradability, low toxicity, and the ability to overcome biological barriers. For these reasons, much attention is paid to the amphiphile-based carriers composed of natural building blocks, lipids, and their structural analogues and synthetic surfactants that are capable of self-assembly with the formation of a variety of supramolecular aggregates. The latter are dynamic structures that can be used as nanocontainers for hydrophobic drugs to increase their solubility and bioavailability. In this section, biodegradable cationic surfactants bearing cleavable fragments are discussed, with ester- and carbamate-containing analogs, as well as amino acid derivatives received special attention. Drug delivery through the biological barriers is a challenging task, which is highlighted by the example of transdermal method of drug administration. In this paper, nonionic surfactants are primarily discussed, including their application for the fabrication of nanocarriers, their surfactant-skin interactions, the mechanisms of modulating their permeability, and the factors controlling drug encapsulation, release, and targeted delivery. Different types of nanocarriers are covered, including niosomes, transfersomes, invasomes and chitosomes, with their morphological specificity, beneficial characteristics and limitations discussed.  相似文献   

18.
纳米材料由于其独特的光、电、磁、力学等性质,成为了构建功能材料与器件的理想基元。实现纳米粒子的精确组装,是探究粒子之间的耦合聚集性质和制备宏观功能器件的基础。但是由于纳米粒子的小尺寸以及在溶液中运动的随机性与复杂性,精准控制纳米粒子组装体的形貌以及在空间中的相对位置仍存在巨大挑战。为了将纳米粒子组装成理想的有序结构,许多控制粒子组装的策略与方法得到发展。本文首先概述了纳米粒子自组装的控制方法与典型形貌,着重分析了影响粒子精准排布的因素与控制方法,并对纳米粒子及其组装体的光学性质与器件应用的最新研究进展进行了讨论,最后对目前纳米粒子精准组装所面临的挑战以及未来发展的方向进行了展望。  相似文献   

19.
采用脱矿物质、提取腐殖酸等方法结合ICP-MS对伊敏15、16煤中的32种微量元素的含量及其赋存特征进行了分析。与地壳克拉克值及中国侏罗-白垩纪煤和世界褐煤中微量元素含量相比,伊敏褐煤中微量元素没有明显富集。脱矿物质处理后,Ni明显富集,As略比原煤高,其他微量元素都低于原煤。原煤提取腐殖酸和脱矿物煤提取腐殖酸中Ni、Mo、Cd、Sn、W明显富集,这表明Ni、Mo、Cd、Sn、W和腐殖酸形成了稳定的有机态化合物。原煤提取腐殖酸残煤和脱矿物煤提取腐殖酸残煤中V、Ni、As富集,表明V、Ni、As与煤的大分子结构形成了稳定的有机态化合物。根据微量元素和灰分的相关性系数,把微量元素分为以下几类:无机富集元素Cr、U;亲无机元素Cu、Cd、In、Sn、Ga、Y、Zr、Hf、Bi、Th;偏无机元素Be、Sc、Rb、Sr、Nb、Cs、Ta、Pb;偏有机元素V、As、Tl、Ba、Se;亲有机元素Li、Co、W;有机富集元素Ni、Zn、Mo、Sb。  相似文献   

20.
赵燕青  许文辉  贾琼 《色谱》2022,40(10):862-871
蛋白质的磷酸化和糖基化作为研究最广泛的两种翻译后修饰(PTMs),在疾病的早期无创诊断、预后和治疗评估中表现出越来越大的潜力。蛋白质的异常磷酸化和糖基化经常被用于临床蛋白质组学研究和疾病相关生物标志物的发现。目前已有多种材料被开发用于磷酸化肽和糖肽的富集研究,其中,智能响应材料由于具有独特的响应特性,已被陆续报道用于磷酸化肽和糖肽的富集。智能响应材料可对外界刺激做出响应,发生结构和性质上的变化,将光、电、热、机械等信号转化为生物化学信号。响应分子是决定智能响应材料响应特性的先决条件,它们在不同刺激条件下(如温度、pH、光、机械应力、电磁场等)的可逆异构化将导致材料的宏观物理和化学性质的动态变化。与传统材料相比,智能响应材料可以可逆地“打开”和“关闭”,具有更好的可调控性。由于引起智能材料响应的刺激信号对其性能具有重要的影响,综述根据施加的刺激种类对智能响应材料进行分类,具体分为外源性响应材料和内源性响应材料,且分别总结了外源性响应材料、内源性响应材料以及内外源共同响应材料在磷酸化肽和糖肽富集方面的工作。此外,综述对智能响应材料在磷酸化肽和糖肽富集方面的发展前景进行了展望,并且提出了智能响应材料在其他蛋白质翻译后修饰方面的应用中存在的挑战。  相似文献   

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