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171.
Although cocrystallization has provided a promising platform to develop new organic optoelectronic materials, it is still a big challenge to purposely design and achieve specific optoelectronic properties. Herein, a series of mixed-stacking cocrystals (TMFA, TMCA, and TMTQ) were designed and synthesized, and the regulatory effects of the acceptors on the co-assembly behavior, charge-transfer nature, energy-level structures, and optoelectronic characteristics were systematically investigated. The results demonstrate that it is feasible to achieve effective charge-transport tuning and photoresponse switching by carefully regulating the intermolecular charge transfer and energy orbitals. The inherent mechanisms underlying the change in these optoelectronic behaviors were analyzed in depth and elucidated to provide clear guidelines for future development of new optoelectronic materials. In addition, due to the excellent photoresponsive characteristics of TMCA, TMCA-based phototransistors were investigated with varying light wavelength and optical power, and TMCA shows the best performance among all reported cocrystals under UV illumination.  相似文献   
172.
建立食品药品检验机构仪器设备计量的信息化规范管理方法。总结了传统人工计量管理的弊端,提出计量信息化管理的流程,将计量信息化管理分为计量计划申报、计量应急申报、计量信息登记、计量结果确认4个步骤,详细介绍了4个步骤中信息管理的主要内容及注意事项。建立食品药品检验机构仪器设备计量信息化管理的标准化规程,可以为仪器设备计量信息的动态监管提供支持。  相似文献   
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A novel approach to nanoscale broadband viscoelastic spectroscopy is presented. The proposed approach utilizes the recently developed modeling-free inversion-based iterative control (MIIC) technique to achieve accurate measurement of the material response to the applied excitation force over a broad frequency band. Scanning probe microscope (SPM) and nanoindenter have become enabling tools to quantitatively measure the mechanical properties of a wide variety of materials at nanoscale. Current nanomechanical measurement, however, is limited by the slow measurement speed: the nanomechanical measurement is slow and narrow-banded and thus not capable of measuring rate-dependent phenomena of materials. As a result, large measurement (temporal) errors are generated when material is undergoing dynamic evolution during the measurement. The low-speed operation of SPM is due to the inability of current approaches to (1) rapidly excite the broadband nanomechanical behavior of materials, and (2) compensate for the convolution of the hardware adverse effects with the material response during high-speed measurements. These adverse effects include the hysteresis of the piezo actuator (used to position the probe relative to the sample); the vibrational dynamics of the piezo actuator and the cantilever along with the related mechanical mounting; and the dynamics uncertainties caused by the probe variation and the operation condition. In the proposed approach, an input force signal with frequency characteristics of band-limited white-noise is utilized to rapidly excite the nanomechanical response of materials over a broad frequency range. The MIIC technique is used to compensate for the hardware adverse effects, thereby allowing the precise application of such an excitation force and measurement of the material response (to the applied force). The proposed approach is illustrated by implementing it to measure the frequency-dependent plane-strain modulus of poly(dimethylsiloxane) (PDMS) over a broad frequency range extending over 3 orders of magnitude (~1 Hz to 4.5 kHz).  相似文献   
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A facile and efficient synthetic methodology for the preparation of aza-pyrimidone and beno-pyrimidone derivatives is described, in which the triazinone ring and dihydroquinazolin-2(1H)-one was convenient constructed. The structures of all the newly synthesized compounds were characterized by mass, 1H NMR, and infrared spectroscopy. In additional, the crystal of pymetrozine was obtained to find useful information such as configuration and molecular action mechanisms.  相似文献   
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The fabrication of room-temperature organic phosphorescence and afterglow materials, as well as the transformation of their photophysical properties, has emerged as an important topic in the research field of luminescent materials. Here, we report the establishment of energy landscapes in dopant-matrix organic afterglow systems where the aggregation states of luminescent dopants can be controlled by doping concentrations in the matrices and the methods of preparing the materials. Through manipulation by thermodynamic and kinetic control, dopant-matrix afterglow materials with different aggregation states and diverse afterglow properties can be obtained. The conversion from metastable aggregation state to thermodynamic stable aggregation state of the dopant-matrix afterglow materials to leads to the emergence of intriguing afterglow transformation behavior triggered by thermal and solvent annealing. The thermodynamically unfavorable reversible afterglow transformation process can also be achieved by coupling the dopant-matrix afterglow system to mechanical forces.  相似文献   
180.
正The Chang'E-3(CE-3)mission began with a smooth countdown and flawless launch on the Long March 3B rocket from the Xichang satellite launch center at 01:30 CST on December 2,2013.It landed on the northeastern Imbrium basin(340.49°E,44.12°N)at 21:11 CST on December 14,2013,and the Yutu rover was deployed from the lander the next morning at 04:35.The lander was equipped with a number of remote-sensing  相似文献   
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