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101.
In order to study the collisional quantum interference (CQI) on rotational energy transfer in atom-diatom system, we have studied the relation of the integral interference angle and differential interference angle in Na+Na2 (A1Σ+u, v=8∽b3Π0u, v=14) collision system. In this paper, based on the first-Born approximation of time-dependent perturbation theory and takinginto accounts the anisotropic effect of Lennard-Jones interaction potentials,we present a theoretical model of collisional quantum interference inintramolecular rotational energy transfer, and a relationship betweendifferential and integral interference angles. 相似文献
102.
带式输送机弯曲变形阻力理论研究 总被引:2,自引:0,他引:2
为了减小带式输送机的弯曲阻力,基于黏弹性材料在动载荷下的能耗理
论,对输送带运行时的弯曲变形能耗机理进行了分析,推导出输送带弯曲变形阻力系数的近似理
论公式,并通过试验验证了公式的正确性. 利用公式对各因素对弯曲阻力系数
的影响规律进行了探讨,结果表明可以通过选配合适的输送带橡胶材料获得合适的
输送带黏弹性参数,并结合调整输送带、输送机的结构参数达到降低输送机弯曲阻力的目的. 相似文献
103.
L. M. Sabirov D. I. Semenov T. M. Utarova Kh. S. Khaidarov 《Physics of Wave Phenomena》2011,19(3):177-183
The dependence of the hypersonic velocity V in an aqueous solution of tertiary butyl alcohol on the solution temperature t has been measured from the Mandelshtam-Brillouin scattering spectra. A change in the temperature derivative of the velocity,
dV/dt, in a narrow range from ≈43 to ≈44°C, with jumps at its boundaries, is revealed. The measurement results and their comparison
with the previous data indicate the existence of structural transitions with respect to temperature and concentration in these
solutions. 相似文献
104.
针对强耦合方法求解风与柔性结构流固耦合作用时,大量计算资源都耗费在对强耦合方程求解中这一弊端,本文研究了强耦合方程的预处理求解方法。在风与柔性结构流固耦合作用的强耦合整体方程的基础上,将时空离散和线性化后的类似结构方程看成是鞍点问题,首先推导得到了类似结构方程的预处理矩阵;再基于此推导出了强耦合整体方程的预处理矩阵。首先采用预处理方法对经典二维流固耦合问题进行了计算,验证了提出的预处理矩阵的正确性;然后对风与三维膜结构的流固耦合作用进行了分析,评估了所提出预处理方法的相关计算参数。计算结果表明,所提出的预处理方法可使强耦合整体方程的求解在计算精度和计算效率上都得到较大提升,证明本文提出的预处理方法适用于风与柔性结构的流固耦合分析。 相似文献
105.
Qiuling Zhao Zhen Zhang Li Xu Ted Xia Nan Li Jianli Liu Xiaohong Fang 《Analytical and bioanalytical chemistry》2014,406(12):2949-2955
A novel enzyme-linked aptamer assay (ELAA) with the aid of Exonuclease I (Exo I) for colorimetric detection of small molecules was developed. The fluorescein isothiocyanate (FITC)-labeled aptamer was integrated into a double-stranded DNA (dsDNA). In the presence of target, the binding of aptamer with target protected the aptamer from Exo I degradation, which resulted in the FITC tag remaining on the aptamer. Then, the anti-FITC-HRP conjugate was used to produce an optically observable signal. By monitoring the color change, we were able to detect two model molecules, ATP and L-argininamide, with high selectivity and high sensitivity even in the serum matrix. It is expected to be a simple and general ELAA method with wide applicability. Figure
Sensing strategy for exonuclease I-aided enzyme-linked aptamer assay 相似文献
106.
以水热合成法制备的一维取向n型ZnO纳米线阵列为衬底,采用电化学沉积法在其上沉积生长一层p型Cu2O半导体包覆层,制备出了新型ZnO/Cu2O异质结纳米线阵列光敏器件.利用XRD、SEM、TEM、XPS、PL及光响应特性等测试方法对样品的形貌、晶体结构、化学成分及光电特性进行了分析表征.研究了生长条件对ZnO/Cu2O异质结纳米线阵列各种特性的影响.研究发现,适宜的沉积电压和沉积时间是保证ZnO/Cu2O异质结光敏器件具有适宜厚度核壳包覆层及较好光响应特性的关键因素.研究结果为ZnO及Cu2O半导体材料在光敏器件中的应用提供了实验基础. 相似文献
107.
This paper deals with the problem of damping driveline oscillations, which is crucial to improving driveability and passenger comfort. Recently, this problem has received an increased interest due to the introduction in several production vehicles of the dual-clutch powershift automatic transmission with dry clutches. This type of transmission improves fuel economy, but it results in a challenging control problem, due to driveline oscillations. These oscillations, also called “shuffles”, occur during gear-shift, while traversing backlash or when tip-in and tip-out maneuvers are performed. The contribution of this paper is to demonstrate that horizon-1 model predictive control based on flexible Lyapunov functions and piecewise affine drivetrain models with three inertias provides an effective solution to driveline oscillation damping. Several simulations based on realistic scenarios show that the proposed control scheme can handle both the performance and physical constraints, and the strict limitations on the computational complexity. 相似文献
108.
The super-hydrophobic and IR-reflectivity hollow glass microspheres (HGM) was synthesized by being coated with anatase TiO2 and a super-hydrophobic material. The super-hydrophobic self-cleaning property prolong the life time of the IR reflectivity. TBT and PFOTES were firstly applied and hydrolyzed on HGM and then underwent hydrothermal reaction to synthesis anatase TiO2 film. For comparison, the PFOTES/TiO2 mutual-coated HGM (MCHGM), PFOTES single-coated HGM (F-SCHGM) and TiO2 single-coated HGM (Ti-SCHGM) were synthesized as well. The MCHGM had bigger contact angle (153°) but smaller sliding angle (16°) than F-SCHGM (contact angle: 141.2°; sliding angle: 67°). Ti-SCHGM and MCHGM both showed similar IR reflectivity with ca. 5.8% increase compared with original HGM and F-SCHGM. For the thermal conductivity, coefficients of F-SCHGM (0.0479 W/(m K)) was basically equal to that of the original HGM (0.0475 W/(m K)). Negligible difference was found between the thermal conductivity coefficients of MCHGM-coated HGM (0.0543 W/(m K)) and Ti-SCHGM (0.0546 W/(m K)). 相似文献
109.
Zhen-Yu Cui You-Yi Xu Li-Ping Zhu Jian-Yu Wang Zhen-Yu Xi Bao-Ku Zhu 《Journal of membrane science》2008
Microporous poly(vinylidene fluoride)/polyethylene oxide-co-polypropylene oxide-co-polyethylene oxide (PVDF/PEO-PPO-PEO, or PVDF/F127) blend membranes were prepared via thermally induced phase separation (TIPS) process using sulfolane as the diluent. Then they were soaked in a liquid electrolyte to form polymer electrolytes. The effects of F127 weight fraction on the morphology, crystallinity and porosity of the blend membranes were studied. It was found that both electrolyte uptake of blend membranes and ionic conductivity of corresponding polymer electrolytes increased with the increase of F127 weight fraction. The maximum ionic conductivity was found to reach 2.94 ± 0.02 × 10−3 S/cm at 20 °C. Electrochemical stability window was stable up to 4.7 V (vs. Li+/Li). The testing results indicated that the PVDF/F127 blend membranes prepared via TIPS process can be used as the polymer microporous matrices of polymer electrolytes for lithium ion batteries. 相似文献
110.