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1.
Small clusters are entities comprised of assemblies of atoms or molecules which often display properties that differ from the individual components and the bulk and, hence, are considered a unique state of matter. Investigating ones of differing sizes provides information that serves to bridge states of matter and, as recently shown, cluster research bridges many disciplines of science. This plenary lecture focused on the varying properties of matter of restricted size, the ability to produce clusters that mimic elements of the periodic table and, hence, behave as super-atoms that can serve as building blocks for new nanoscale matter with designed properties. Mass spectrometry has in the past, and continues in the future, to play a central role in this field.  相似文献   

2.
The forensic discipline of ignitable liquid and fire debris analysis is rapidly changing. Refinements in existing methods as well as development of new techniques are changing the routine methods of analysis. Optimization of existing extraction techniques and research into novel methods of extracting debris have improved the recovery of ignitable liquids from debris samples. The application of highly specialized instrumentation to problems of sensitivity and matrix interference has resulted in new ways of performing chemical analyses, allowing for improved limits of detection. Preliminary research in novel approaches to ignitable liquid comparisons is being evaluated, with the hopes of providing more detailed information to the field investigators. Research into a variety of areas related to fire debris analysis is ongoing, and will continue to improve the quality of ignitable liquid residue analysis.  相似文献   

3.
In this paper, we focus on the recent advances on the physical chemistry of lignin. Emerging trends of incorporating lignin in promising future applications such as controlled release, saccharification of lignocelluloses, bioplastics, composites, nanoparticles, adsorbents and dispersants, in electro-chemical applications and carbon fibers, are also reviewed. We briefly describe the complexity of the lignin structure that influences the solution behavior, both as a macromolecule and a colloid, as well as the potential of being a renewable precursor in the development of high-value applications. Special attention is paid on summarizing the present knowledge on lignin colloidal stability and surface chemistry.  相似文献   

4.
Abstract: Catalysis of GTP of MMA with nucleophilic anions on cross-linked polystyrene supports was studied. With anion-bound supported catalyst, evidence is presented for formation in solution of ester enolates as reaction intermediates. Study of the cyanide-catalyzed initiation of GTP of MMA by TMSCN, has provided quantitative data for the association constant Ka for the complexation of cyanide by TMSCN and, by inference, an upper limit for the Ka for the association of this nucleophilic anion with silyl ketene acetals. The effects of i-propyl- and t-butoxy-silyl analogs of TMSCN on anion-complexation and on initiation and propagation of GTP are discussed. Coordination by hydrogen-bonding of nucleophilic anions to acetonitrile is shown to be the mechanism for “livingness-enhancement” of anion-catalyzed GTP at low concentrations of acetonitrile. GTP was used to prepare an ABC triblock dispersant, poly(methacrylic acid)-block-poly(2-phenylethyl methacrylate)-block-poly(ethoxytriethylene glycol methacrylate), and the surface activity of an aqueous solution of the potassum salt was compared with that of other polymer architectures.  相似文献   

5.
Zheng  Yian  Wang  Jintao  Wang  Aiqin 《Cellulose (London, England)》2021,28(9):5269-5292
Cellulose - Kapok fiber (KF) belongs to a type of seed fibers collected from the fruits of Ceiba pentandra tree. From sustainable biomass resource, KF is a naturally abundant cellulose fiber with...  相似文献   

6.
7.
Among the different extraction techniques used at analytical and preparative scale, supercritical fluid extraction (SFE) is one of the most used. This review covers the most recent developments of SFE in different fields, such as food science, natural products, by-product recovery, pharmaceutical and environmental sciences, during the period 2007–2009. The revision is focused on the most recent advances and applications in the different areas; among them, it is remarkable the strong impact of SFE to extract high value compounds from food and natural products but also its increasing importance in areas such as heavy metals recovery, enantiomeric resolution or drug delivery systems.  相似文献   

8.
Ma Q  Su X 《The Analyst》2011,136(23):4883-4893
As a unique nanomaterial, quantum dots (QDs) are not only applied in fluorescent labeling and biological imaging, but are also utilized in novel sensing systems. Because QDs have attractive optoelectronic characteristics, QD-based sensors present high sensitivity in detecting specific analytes in the chemical and biochemical fields. In this review, we describe the basic principles and different conjugation strategies in QD-based sensors. An overview of recent advances and various models of QD-sensing systems is also provided. Furthermore, perspectives for sensors based on QDs are discussed.  相似文献   

9.
10.
Ding  Fuyuan  Li  Houbin  Du  Yumin  Shi  Xiaowen 《Research on Chemical Intermediates》2018,44(8):4827-4840
Research on Chemical Intermediates - Over the past few decades, self-healing materials derived from chitosan have attracted a great deal of attention due to their excellent physical and biological...  相似文献   

11.
Chi Z  Zhang X  Xu B  Zhou X  Ma C  Zhang Y  Liu S  Xu J 《Chemical Society reviews》2012,41(10):3878-3896
Mechanofluorochromic materials, which are dependent on changes in physical molecular packing modes, have attracted considerable interest over the past ten years. In this review, recent progress in the area of pure organic mechanofluorochromism is summarized, and majority of the reported organic mechanofluorochromic systems are discussed, along with their derived structure-property relationships. The existence of a structural relationship between aggregation-induced emission compounds and mechanofluorochromism is recognized based on our recent results, which considered aggregation-induced emission compounds as a well of mechanofluorochromic materials. The established structure-property relationship will guide researchers in identifying and synthesizing more mechanofluorochromic materials.  相似文献   

12.
Surfactant-mediated wetting and spreading are ubiquitous. Understanding of these phenomena in-depth allows precise tailoring of wetting performance which can contribute to global challenges in the food supply chain, healthcare, ecology and industrial processes. The first part of this review shows how surfactants can be used to improve the efficacy of fertilisers and pesticides in agriculture, enhanced oil recovery, treatment of lung diseases and extinguishing fires involving flammable liquids. The second part provides analysis of recent studies on wetting and spreading over solid substrates. It includes discussion on the effect of surfactants on the outcome of the impact of liquid drops, the wetting state after impact, autophobic effect and spreading kinetics for both partial and complete wetting, including superspreading. Perspectives of future development in the area of surfactant-assisted wetting and spreading on solid substrates are outlined.  相似文献   

13.
As a rigid and planar aza-based heteroaromatic scaffold, hexaazatriphenylene (HAT) exhibits excellent electron-deficient property and high π-π stacking tendency, which makes it an ideal building block in the construction of supramolecular architectures and functional materials. In addition, HATs have also been picked out as building blocks for the construction of novel porous organic polymers, one of the most attractive fields of porous materials in the past decade, which includes intrinsic microporosity (PIMs), π-conjugated microporous polymers (CMPs), and covalent organic frameworks (COFs). In this digest paper, the synthetic methods of HAT derivatives have been briefly introduced and some recent advances of HATs in the applications of supramolecular self-assembly and porous organic materials have been highlighted.  相似文献   

14.
Employing a multiscale systems-based research approach, chemists and chemical engineers at the Center for Environmentally Beneficial Catalysis (CEBC) are collaboratively addressing major grand challenges facing the sustainable manufacture of fuels and chemicals from both traditional and renewable feedstocks. By judiciously combining the principles of green chemistry and green reactor engineering, augmented by valuable insights from industrial partners, CEBC researchers are developing alternative technology concepts that minimize the environmental footprint of chemical manufacturing processes including the reduction of carbon emissions. Such collaborations have resulted in several remarkable discoveries as follows: CO2-expanded liquids (CXLs) as reaction media for selective and inherently safe O2 oxidations including that for terephthalic acid production from p-xylene with potentially reduced solvent burning (i.e., reduced carbon footprint); propylene oxide production with environmentally benign solvents and oxidant, exploiting the compressibility of propylene at ambient temperatures for process intensification; a novel pressure-intensified ethylene oxide process virtually eliminating CO2 formation as a byproduct; highly selective hydroformylation of higher olefins employing CXLs and soluble polymer-supported homogeneous Rh-based catalysts that are easily retained in solution while the product is isolated by membrane filtration; and creation of nanoparticles of transition metal complexes with unique functional properties such as reversible oxygen binding and room-temperature nitric oxide disproportionation. Quantitative economic and environmental impact analyses have been employed to benchmark CEBC's novel technology concepts against conventional processes and to guide research and development. Examples of such advances in green processing are discussed in this review.  相似文献   

15.
The field of Small Molecule Microarray's (SMM's) is an ever-expanding part of the larger microarray field. SMM's are array based detection systems that use small molecules as probes immobilized on a variety of microarray surfaces that are screened against a number of targets for purposes including, but not limited to, protein-small molecule ligand recognition and protein function profiling. This review covers the recent advances in the field with particular emphasis on the successful applications of SMM's, as well as technical advances in platform optimization and novel small molecule immobilization strategies.  相似文献   

16.
The abuse of antibiotics will cause an increase of drug-resistant strains and environmental pollution,which in turn will affect human health.Therefore,it is important to develop effective detection techniques to determine the level of antibiotics contamination in various fields.Compared with traditional detection methods,electrochemical sensors have received extensive attention due to their advantages such as high sensitivity,low detection limit,and good selectivity.In this mini review,we summarized the latest developments and new trends in electrochemical sensors for antibiotics.Here,modification methods and materials of electrode are discussed.We also pay more attention to the practical applications of antibiotics electrochemical sensors in different fields.In addition,the existing problems and the future challenges ahead have been proposed.We hope that this review can provide new ideas for the development of electrochemical sensors for antibiotics in the future.  相似文献   

17.
Sodium-ion batteries(SIBs)have been considered as an ideal choice for the next generation large-scale energy storage applications owing to the rich sodium resources and the analogous working principle to that of lithium-ion batteries(LIBs).Nevertheless,the larger size and heavier mass of Na+ion than those of Li+ion often lead to sluggish reaction kinetics and inferior cycling life in SIBs compared to the LIB counterparts.The pursuit of promising electrode materials that can accommodate the rapid and stable Na-ion insertion/extraction is the key to promoting the development of SIBs toward a commercial prosperity.One-dimensional(1 D)nanomaterials demonstrate great prospects in boosting the rate and cycling performances because of their large active surface areas,high endurance for deformation stress,short ions diffusion channels,and oriented electrons transfer paths.Electrospinning,as a versatile synthetic technology,features the advantages of controllable preparation,easy operation,and mass production,has been widely applied to fabricate the 1 D nanostructured electrode materials for SIBs.In this review,we comprehensively summarize the recent advances in the sodium-storage cathode and anode materials prepared by electrospinning,discuss the effects of modulating the spinning parameters on the materials’micro/nano-structures,and elucidate the structure-performance correlations of the tailored electrodes.Finally,the future directions to harvest more breakthroughs in electrospun Na-storage materials are pointed out.  相似文献   

18.
Recent progress in hybrid materials science   总被引:2,自引:0,他引:2  
This themed issue of Chemical Society Reviews reviews recent progress made in hybrid materials science. Guest editors Clément Sanchez, Susumu Kitagawa and Ken Shea introduce the issue and the academic and industrial importance of the field.  相似文献   

19.
Recent advances and applications in 1,2,4,5-tetrazine chemistry   总被引:2,自引:0,他引:2  
  相似文献   

20.
Biosensors have shown great potential for health care and environmental monitoring. The performance of biosensors depends on their components, among which the matrix material, i.e., the layer between the recognition layer of biomolecule and transducer, plays a crucial role in defining the stability, sensitivity and shelf-life of a biosensor. Recently, zinc oxide (ZnO) nanostructures and thin films have attracted much interest as materials for biosensors due to their biocompatibility, chemical stability, high isoelectric point, electrochemical activity, high electron mobility, ease of synthesis by diverse methods and high surface-to-volume ratio. ZnO nanostructures have shown the binding of biomolecules in desired orientations with improved conformation and high biological activity, resulting in enhanced sensing characteristics. Furthermore, compatibility with complementary metal oxide semiconductor technology for constructing integrated circuits makes ZnO nanostructures suitable candidate for future small integrated biosensor devices. This review highlights recent advances in various approaches towards synthesis of ZnO nanostructures and thin films and their applications in biosensor technology.  相似文献   

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