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41.
The effects of beam wander corrected and pointing errors on the average capacity of a non-Kolmogorov turbulent atmosphere communication channel are studied. The gamma–gamma irradiance probability density function model has been considered to include the effects of non-Kolmogorov turbulence. An expression for the average capacity under beam wander corrected, pointing errors and the spectral index of refractive-index fluctuation. Simulation results for effects of circular detection aperture of radius, atmosphere turbulence strength and wavelength on average capacity are presented. Our results show that the average capacity has an oscillation in the case of short propagation distance, but in the case of long propagation distance, it has gradually reduced curves. And the turbulence strength has a strong influence on average capacity. In general, turbulence reduces the average capacity; it can reduce average capacity by increasing of the power law α. We can ignore the little effects of wavelength increases on the average capacity.  相似文献   
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通过受限空间油气爆燃可视化实验发现,在不同初始油气体积分数下,爆燃火焰呈现出不同的表观特征,据此提出了受限空间油气爆燃的3种火焰形态,即光滑球形火焰、褶皱球形火焰和卷曲絮状火焰。分析了3种火焰形态的形成机理,并通过实验观测与理论分析,给出了区分3种火焰形态的临界条件。结合实验中采集到的关键参数,总结了不同的火焰形态下受限空间油气爆燃的反应产物、最大压力、升压速率、反应时间、火焰强度等关键参数的特征与变化规律。  相似文献   
44.
Gao  Jian  Ma  Na  Tian  Jianjun  Shen  Cong  Wang  Lili  Yu  Pengfei  Chu  Yuanyuan  Liu  Wei  Tan  Xiaoyao  Li  Xifei  Yin  Zhen 《Journal of Solid State Electrochemistry》2018,22(2):519-525
Journal of Solid State Electrochemistry - One-pot strategy to fabricate N, P co-doping carbon was developed based on the functional ionic liquid (IL) as the N, P, and C precursors. The IL featuring...  相似文献   
45.
功率对氘代辉光放电聚合物结构和力学性能的影响   总被引:1,自引:0,他引:1  
采用射频辉光放电聚合技术,在低压等离子体聚合装置上开展在5~20 W功率下氘代辉光放电聚合物薄膜的制备及性能研究。利用傅里叶变换红外吸收光谱仪表征薄膜的化学结构,讨论了功率变化对其官能团结构的影响规律。利用元素分析仪和纳米压痕仪表征薄膜中氘原子的相对含量和薄膜的力学性能。研究表明:随着功率的升高,薄膜中的氘含量先升高后降低,在10W时达到最大,薄膜中SP3 CD的相对含量增加,SP3 CD2的相对含量减小;聚合物薄膜的硬度和杨氏模量均随功率的增加而减小。  相似文献   
46.
Controlled release formulation of pesticides is highly desirable for attaining the most effective utilization of the pesticide as well as reducing environmental pollution. Nano-sized controlled release formulations can provide better penetration through cuticle and deliver the active ingredients efficiently to the targeted tissue. In this study, a novel strategy for the preparation of a nanoconjugate derived from kasugamycin with amino-modified silica was developed. The kasugamycin was connected with amino-modified silica matrix by an amide bond, which could avoid the initial burst release effectively and prolong the duration remarkably. The results showed the kasuga-silica can protect kasugamycin against photo-degradation effectively and the release rate of the active ingredient of nanoconjugate was related to the temperature, pH value, and the particle size (52.5–315.4 nm). With reduced particle size as well as increased temperature and acidity, the release of the active ingredient was faster. This amide linkage of kasuga-silica could be degraded by amidase effectively. This nanoconjugate displayed a better and a sustained bactericidal efficacy against E. coli than kasugamycin technical, which makes it a potential candidate as a controlled release conjugate for kasugamycin in the future.  相似文献   
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The applications of a new supported tribromide reagent based on poly(vinylbenzyltrimethylammonium hydroxide) resin (Amberlite 717) were reported. This supported tribromide resin was used directly in α-bromination and α-bromoacetalization of acetophenones without any other catalyst under mild conditions. The effects of solvents and the amount of the supported tribromide resin on the reactions were investigated. Under the optimal conditions, most of α-bromo and α-bromoacetal of acetophenones were selectively obtained in excellent yields.  相似文献   
49.
Jianjun Li  Yan Sun  Zhiwei Chen 《合成通讯》2013,43(24):3669-3677
Acylation of imidazolidin-2-one with readily available N-acylbenzotriazoles, in the presence of K2CO3, produced 1-acylimidazolidin-2-ones and N,N′-diacyl-imidazolidin-2-one in moderate to good yields. The utilization of N-acylbenzotriazoles which make the reaction simple and mild, may be especially advantageous when the corresponding acid chlorides are not stable or not easily prepared. It's also an example of the reaction of N-acylbenzotriazoles and amide.  相似文献   
50.
Jianjun Li  Jia Li  Jin Fang 《合成通讯》2013,43(7):1029-1039
A facile and efficient procedure has been developed by one-pot condensation of β-naphthol, aldehydes, and cyclic 1,3-dicarbonyl compounds for the synthesis of 8,9,10,12-tetrahydrobenzo[a]xanthen-11-one or 8,9-dihydrobenzo-[f]cyclopenta[b]chromen-10(11H)-one derivatives catalyzed by p-toluenesulfonic acid under solvent-free and sonication conditions.  相似文献   
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