Wang H.-F.,Pacific Northwest National Laboratory |
Velarde L.,State University of New York at Buffalo |
Gan W.,CAS Xinjiang Technical Institute of Physics and Chemistry |
Fu L.,Pacific Northwest National Laboratory
Annual Review of Physical Chemistry | Year: 2015
Sum-frequency generation vibrational spectroscopy (SFG-VS) can provide detailed information and understanding of the molecular composition, interactions, and orientational and conformational structure of surfaces and interfaces through quantitative measurement and analysis. In this review, we present the current status of and discuss important recent developments in the measurement of intrinsic SFG spectral lineshapes and formulations for polarization measurements and orientational analysis of SFG-VS spectra. The focus of this review is topresent a coherent description of SFG-VS and discuss the main concepts and issues that can help advance this technique as a quantitative analytical research tool for revealing the chemistry and physics of complex molecular surfaces and interfaces. © 2015 by Annual Reviews. All rights reserved.
Chen S.,CAS Xinjiang Technical Institute of Physics and Chemistry |
Chen S.,University of Chinese Academy of Sciences |
Slattum P.,Vaporsens |
Wang C.,CAS Xinjiang Technical Institute of Physics and Chemistry |
Zang L.,University of Utah
Chemical Reviews | Year: 2015
A study is conducted to provide comprehensive information about one-dimensional (1D) self-assembly of PIs, providing a deep understanding of recent progress, along with possible challenges and breakthroughs coming in the future. The basic molecular design and synthetic strategies of PI molecules are described. A complete overview of the 1D self-assembly methodology of PIs then is presented, followed by a summary of the inspiring applications and relevant prospects of the 1D assemblies in photonic and electronic devices.
Ma P.-C.,CAS Xinjiang Technical Institute of Physics and Chemistry |
Ma P.-C.,Chinese Academy of Sciences |
Zhang Y.,China Aerospace Science and Technology Corporation
Renewable and Sustainable Energy Reviews | Year: 2014
The global market for wind energy has increased exponentially in the past few decades, and there is a continuous effort to develop cost-effective materials with higher strength to mass ratio for wind blades. With unique structural and transport properties, carbon nanotubes (CNTs) have attracted much interest as the reinforcement to develop polymer-based nanocomposites delivering exceptional mechanical properties and multi-functional characteristics. In light of previous and current status in carbon-based materials, herein the suitabilities of CNT/polymer nanocomposites for wind blade materials are analyzed. Special emphasis is placed on the mechanical, fatigue, electrical, thermal and barrier properties of CNT/polymer nanocomposites, which are important considerations when selecting suitable materials for wind blades with larger rotary radius. The application of CNT/polymer nanocomposites as sensory materials for the monitoring of defects in composite structures is also discussed. Finally, based on the progress made so far, some suggestions paving the way for the large commercialization of these nanocomposites for wind blades are presented. © 2013 Elsevier Ltd. All rights reserved.
Zu B.,CAS Xinjiang Technical Institute of Physics and Chemistry |
Guo Y.,CAS Xinjiang Technical Institute of Physics and Chemistry |
Dou X.,CAS Xinjiang Technical Institute of Physics and Chemistry
Nanoscale | Year: 2013
Optoelectronic sensing of gas phase hazardous chemicals is a newly explored field, which shows great advantages towards low concentration sensing when compared to normal gas sensing in the dark. Here, based on the recent progress on nanostructured vapor phase explosive gas sensors operated in dark conditions, the attractiveness of developing optoelectronic sensors for vapor phase explosive detection was highlighted. Furthermore, we try to propose some new insights to enhance optoelectronic sensing of vapor phase explosives. We suggest employing photocatalysis principles to enhance the sensitivity and employing a molecular imprinting technique (MIT) to enhance the selectivity. © 2013 The Royal Society of Chemistry.
Cao Y.,CAS Xinjiang Technical Institute of Physics and Chemistry |
Zhao M.,CAS Xinjiang Technical Institute of Physics and Chemistry
Process Biochemistry | Year: 2012
Eicosapentaenoic acid (EPA) is an ω3 polyunsaturated fatty acid which has been demonstrated to play important roles in a number of aspects of human health. EPA is traditionally obtained from marine fish oils. However, the shrinking fish populations are making the sustainability of these sources questionable. Consequently, alternative sources of EPA are being sought, especially from marine microalgae, bacteria, and fungi. These microorganisms contain relatively large amounts of high-quality EPA and they are the primary producers of this important fatty acid. There are two distinct pathways for EPA de novo biosynthesis in microbial systems: the desaturation and elongation pathway and the polyketide pathway. Genes involved in the biosynthetic pathways have been identified from different microorganisms and characterized in depth. In addition, numerous strategies have been developed for commercial production of EPA by microbial fermentation, among which strain improvements by genetic engineering could provide high-yield producers of EPA. In this review, we summarize recent efforts and experiences devoted to metabolic engineering of various microorganisms that lead to efficient biocatalysts for the production of EPA, as well as the key limitations and challenges. The combination of traditional biochemistry and molecular biology with new systems biology and synthetic biology tools will provide a better view of EPA biosynthesis and a greater potential of microbial production. Continued advances in metabolic engineering will help to improve the final titer, productivity, and yield of EPA. © 2012 Elsevier Ltd. All rights reserved.
CAS Xinjiang Technical Institute of Physics and Chemistry | Date: 2014-01-23
The present invention relates to a barium tetraborate compound and a barium tetraborate non-linear optical crystal, and a preparation method and use thereof, wherein the chemical formulae of the barium tetraborate compound and the non-linear optical crystal thereof are both BaB_(4)O_(7), with a molecular weight of 292.58; the barium tetraborate non-linear optical crystal has a non-centrosymmetric structure, which belongs to a hexagonal system, and has a space group P6_(5 )and lattice parameters of a=6.7233(6) , c=18.776(4) , V=735.01(17) ^(3), and Z=6, wherein the powder frequency-doubled effect thereof is two times that of KDP (KH_(2)PO_(4)), and the ultraviolet cut-off edge is lower than 170 nm. The barium tetraborate compound is synthesised by a solid-phase reaction method; the barium tetraborate non-linear optical crystal is grown by a high-temperature molten solution method; and the crystal has a moderate mechanical hardness, is easy to cut, polish and store, and is widely applicable in the non-linear optics of a double-frequency doubling generator, an upper frequency converter, a lower frequency converter or an optical parameter oscillator etc.
CAS Xinjiang Technical Institute of Physics and Chemistry | Date: 2014-05-28
A preparation method and application of a Na_(3)Ba_(2)(B_(3)O_(6))_(2)F birefringent crystal, the crystal having a chemical formula of Na_(3)Ba_(2)(B_(3)O_(6))_(2)F, and belonging to a hexagonal crystal system, the space group being P6_(3)/m, and the lattice parameters comprising a=7.3490(6) , c=12.6340(2) , V=590.93(12) ^(3), Z=2; the crystal is used for an infrared/deep ultraviolet waveband, and is an uniaxial negative crystal, n_(e)
CAS Xinjiang Technical Institute of Physics and Chemistry | Date: 2013-05-31
The present invention relates to a cesium borosilicate compound, a nonlinear optical crystal of cesium borosilicate, and a preparation method therefor and a use thereof. The cesium borosilicate compound has a chemical formula of Cs_(2)B_(4)SiO_(9 )and a molecular weight of 481.15, and is prepared using a solid phase method. The nonlinear optical crystal of the cesium borosilicate compound has a chemical formula of Cs_(2)B_(4)SiO_(9 )and a molecular weight of 481.15, does not have a center of symmetry, belongs to the tetragonal system with space group I 4 and unit-cell parameters a=6.731(3) , c=9.871(9) and V=447.2(5) ^(3), and has a wide transmittance range. The shortest ultraviolet cutoff edge is smaller than 190 nm, the frequency doubling effect of the crystal is 4.6 KDP, and the crystal is grown by a high-temperature solution spontaneous crystallization method and a flux method. The crystal has advantages of high growth rate, being transparent and inclusion free, low cost having a wide transmittance range, high hardness, good mechanical property, being crack resistant and not prone to deliquescence, being easy to process and store, and the like. The crystal is widely applied to manufacturing of nonlinear optical devices such as frequency doubling generators, frequency up-converters, frequency down-converters or optical parametric oscillators.
CAS Xinjiang Technical Institute of Physics and Chemistry | Date: 2014-01-23
Provided area deep ultraviolet non-linear optical crystal of barium borate hydrate, a preparation method therefor and the use thereof. The chemical formula of the crystal is Ba_(2)B_(H)O_(22)H_(7), belonging to monoclinic system, with the space group thereof being P2_(1), the crystal cell parameters thereof being a=6.7719(10) , b=21.1195(4) , c=6.8274(10) , =119.3950(10) , and the molecular weight thereof being 752.65. The non-linear optical crystal of borate is obtained by means of programmed cooling or natural cooling using a hydrothermal method. The crystal powder has a frequency-doubled effect of about 2 times that of KDP (KH_(2)PO_(4)) and an ultraviolet cut-off edge of below 175 nm and can be used as a deep ultraviolet non-linear optical crystal. The growth process of the crystal has advantages such as simple, a low cost, a low toxicity, a short growth cycle, stable physical and chemical properties, etc. The deep ultraviolet non-linear optical crystal of barium borate hydrate Ba_(2)B_(11)O_(22)H_(7 )is widely used in the preparation of non-linear optical devices such as frequency doubling generators, upper frequency converters, lower frequency converters, optical parametric oscillators etc.
CAS Xinjiang Technical Institute of Physics and Chemistry | Date: 2011-01-12
The present invention provides a barium fluoroborate compound, a nonlinear optical crystal and the preparation method and use thereof. Both of the barium fluoroborate compound and the nonlinear optical crystal have a chemical formula of Ba_(4)B_(11)O_(20)F. The crystal belongs to orthorhombic crystal system, has a space group Cmc2_(1 )with unit cell parameters of a=18.802(3) , b=10.7143(19) , c=8.6113(14) , V=1734.7(5) ^(3). The crystal has a powder second harmonic generation efficiency of 10 times that of KDP (KH_(2)PO_(4)). The ultraviolet cutoff wavelength is about 170 nm. The barium fluoroborate compound is prepared by a solid-state reaction. The barium fluoroborate nonlinear optical crystal prepared by a high temperature melting liquid method has large hardness and is easy to be cut, polished and stored. This crystal can be used widely in preparing the nonlinear optical devices of the second harmonic generator, the up frequency converter, the down frequency converter or the optical parametric oscillator or the like.