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排序方式: 共有37条查询结果,搜索用时 15 毫秒
1.
CCD对高空间分辨率波前干涉检测的影响   总被引:2,自引:2,他引:0  
推导并用实验验证了光强与入射波前在单位像元面积里成近似线性关系,从而得到入射波前经CCD采样后的功率谱密度(PSD)公式.根据该公式,模拟分析了影响CCD采集系统的系统传递函数的各个因素:入射波前、CCD的填充因子及CCD的曝光时间,得出了他们与系统传递函数的定性关系,并且通过实验明确CCD曝光时间对高空间分辨率波前检测不确定度的影响,为高空间分辨率干涉设计提供了理论依据.  相似文献   
2.
本文提出了一种新的离子选择性电极分析方法,即等电位差-标准加入法。本方法已用于氟的测定。进行了理论数据验证及误差分析,标准溶液的回收率为96.6%-104.3%。本方法的影响因素少、准确度好、操作及计算简便。  相似文献   
3.
An angular‐shaped naphthalene tetracarboxylic diimide (NDI) was designed and synthesized as a new building block for n‐type conjugated polymers to tune their energy levels. Three n‐type copolymers incorporating this angular‐shaped NDI as the acceptor moiety were obtained by Stille coupling reactions and had number average molecular weights of 18.7–73.0 kDa. All‐polymer bulk‐heterojunction solar cells made from blends of these polymers with poly(3‐hexylthiophene) gave a power conversion efficiency up to 0.32% and exhibited an open‐circuit voltage (Voc) up to 0.94 V due to their relative high‐lying lowest unoccupied molecular orbital energy levels. The high Voc of 0.94 V is higher than that of solar cells based on linear‐shaped NDI‐containing polymers (<0.6 V). The results indicate that the angular‐shaped NDI is a promising building block for constructing nonfullerene polymer acceptors for solar cells with high open‐circuit voltages. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   
4.
We present recent progresses on applying the theoretical models and computational tools in assessing the performance of organic solar cells, especially the bulk heterojunction solar cells. Both the continuum device model and the dynamic Monte Carlo model are developed to investigate the photocurrent-voltage characteristics based on the exciton and charge carrier dynamics. Insights into key factors influencing the organic photovoltaic performances have been gained from these studies.  相似文献   
5.
富碳炸药在爆轰过程中可产生团簇分子,而现有的实验手段不能直接观测团簇分子的形成过程.本文采用ReaxFF/lg力场对梯恩梯(TNT)在不同温度下的热分解过程进行了模拟.研究发现:团簇分子在反应初始阶段形成缓慢,大约一次增加一个TNT相对分子质量.随着反应进行,团簇分子迅速增大,最大团簇分子相对分子质量可达8000~10000,约占体系质量的18%.分析团簇分子的结构发现,团簇分子中一部分苯环被破坏,形成五元环和夹杂N、O原子的六元环,在3500 K条件下还形成了更为复杂的七元环等结构.通过体积膨胀和直接降温的方法,研究了团簇分子的稳定性:体积膨胀使得团簇分子迅速分解;而直接降温,团簇分子又聚合成更大的团簇.分析类石墨结构的产生过程,发现先膨胀然后降温是必不可少的步骤.比较团簇分子和TNT分子中各原子质量所占比,团簇分子中C原子质量比始终在增加.  相似文献   
6.
A chiral tripod-terpyridine ligand is known to coordinate with Ag+. These complexes self-assemble into chiral aggregates at room temperature. Molecular dynamic simulation reveals the cooperation of tripodal ligand structures with Ag(I) cations, which leads to the formation of helical aggregations, thus the chirality.  相似文献   
7.
A series of compounds based on the angular-shaped naphthalene tetracarboxylic diimide core have been synthesized, characterized and used as active layers of organic field-effect transistors (OFETs). The fabricated OFET devices exhibit n-type semiconducting characteristics, demonstrating the first examples of semiconductors based on angular-shaped naphthalene tetracarboxylic diimides.  相似文献   
8.
利用高纯铜粉与稀土矿石粉末均匀混合压片制样.混合15种高纯稀土氧化物制样建立标准工作曲线,校正15种稀土元素相对灵敏度因子,再进行定量分析.结果 表明,稀土元素工作曲线的线性方程相关系数R2均大于0.996,相对标准偏差(RSD)小于5%,满足定量分析要求.测定结果与电感耦合等离子体质谱法(ICP-MS)和电感耦合等离...  相似文献   
9.
K2NaAlF6:Ce3+和KAlF4:Ce3+磷光体的光谱特性   总被引:3,自引:0,他引:3  
张吉林  洪广言 《发光学报》1991,12(3):224-229
采用高温固相反应法,在Ar气氛中,合成了K2NaAlF6和KAlF4基质化合物.分别测定了它们的结构,并计算了晶胞参数.测定了K2NaAlF6:Ce3+和KAlF4:Ce3+磷光体的激发光谱和荧光光谱,根据Ce3+的光谱结构的特点,讨论了Ce3+的取代格位.  相似文献   
10.
In this study, a series of well‐defined liquid crystalline molecular brushes with dual “jacketing” effects, polynorbornene‐g‐poly{2,5‐bis[(4‐methoxyhenyl)oxycarbonyl] styrene} (PNb‐g‐PMPCS), were synthesized by the “grafting through” method from ring opening metathesis polymerization of α‐norbornenyl‐terminated PMPCS. The rigid PMPCS side chain was synthesized by Cu(I)‐catalyzed atom transfer radical polymerization initiated by N‐[(2‐bromo‐2‐methylpropanoyl)ethyl]‐cis‐5‐norbornene‐exo‐2,3‐dicarboximide. The chemical structures of the molecular brushes were confirmed by 1H NMR and gel permeation chromatography (GPC), and the thermal properties were studied by thermogravimetric analysis (TGA). GPC results reveal that the molecular brushes have relatively narrow polydispersities. TGA results show that the molecular brushes have excellent thermal stabilities. The PMPCS side chains in all the molecular brushes form the columnar nematic liquid crystalline phase, which is a little different from the behavior of linear PMPCS possibly due to the confinement or other effects of the brush architecture which leads to decreased order. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2116–2123  相似文献   
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