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1.
The coordination chemistry of f-block elements (lanthanide and actinide) in molten salts has become a resounding topic in view of its great importance to the research and development (R&D) of molten salt reactors and pyroprocessing. In this Review article, a general overview of the coordination chemistry of f-block elements in molten salts is provided including past achievements and recent advances. Particular emphases are placed on the oxidation state, speciation, and solution structure of f-block metal ions in molten salts, as well as their relationships with the salt composition. Furthermore, this review briefly discusses the spectroscopic and theoretical methods that complement each other in revealing the coordination properties.  相似文献   
2.
柴国庆 《数学杂志》1996,16(3):293-298
本文给出了混合型多项式Hammerstein积分方程正解的迭代求法,并将所得结果应用到二阶非线性常微分方程的边值问题  相似文献   
3.
This paper presents a multiobjective hybrid metaheuristic approach for an intelligent spatial zoning model in order to draw territory line for geographical or spatial zone for the purpose of space control. The model employs a Geographic Information System (GIS) and uses multiobjective combinatorial optimization techniques as its components. The proposed hybrid metaheuristic consists of the symbiosis between tabu search and scatter search method and it is used heuristically to generate non-dominated alternatives. The approach works with a set of current solution, which through manipulation of weights are optimized towards the non-dominated frontier while at the same time, seek to disperse over the frontier by a strategic oscillation concept. The general procedure and its algorithms are given as well as its implementation in the GIS environment. The computation has resulted in tremendous improvements in spatial zoning.  相似文献   
4.
Banach空间中一类非线性算子Ishikawa迭代序列收敛定理   总被引:7,自引:1,他引:6  
在一般的Banach空间中,研究了Ishikawa迭代序列收敛问题,去掉了通常文献中关于空间X的一致光滑或S-一致光滑的严格要求,此外,还去掉或减弱了其它某些条件。因而本质地改进了近期文献的一系列相应定理。  相似文献   
5.
The in-plane electrical resistivity and thermoelectric power have been measured on single crystals of La2-xBaxCuO4 at around x=0.125. The room temperature resistivity and thermopower have their maximum values at x=0.125, indicating that the carrier concentration is the minimum and the carriers are most strongly localized at x=0.125. The observed semiconductor-like behaviour can be well described by the weak-localized quasi-two-dimensional state. The steep rise in electric resistivity of the sample at x=0.125 below 70K is attributed to the formation of static stripe-order of holes and spins, which are pinned by the low-temperature tetragonal (LTT) structure, as discovered in La1.48Nd0.4Sr0.12CuO4. The temperature dependence of electric resistivity below 70K is still well described by the formula ρ∝ lnT. A definite change in the slope of thermopower is observed at the low-temperature orthorhombic-LTT structural phase transition temperature. The origin of the 1/8 anomaly is discussed in the text.  相似文献   
6.
分别采用514 nm绿光、488 nm蓝光和390 nm紫外光作为敏化光,633 nm红光作为记录光,详细研究了敏化光波长对氧化(Fe,Ni):LiNbO3晶体全息记录性能的影响.结果表明:随着敏化光波长的逐渐减小,氧化(Fe,Ni):LiNbO3晶体的非挥发全息记录性能逐渐优化,390 nm紫外光是这三种敏化光中最优的敏化光.考虑敏化光的吸收,为了在双中心全息记录中获得最优的性能,应当选择合适波长的敏化光:一方面短波长敏化光能有效地敏化深中心;另一方面短波长敏化光的吸收太强(如对光折变效应无用的基质吸收),不能沿厚度方向有效地敏化晶体,所以实际上需折衷考虑,并从理论上给予了解释.  相似文献   
7.
采用多元芯片方法获得了一系列不同离子注入剂量的GaAsAlGaAs非对称耦合量子阱单元,通过光致荧光谱测量,研究了单纯的离子注入导致的界面混合效应.荧光光谱行为与有效质量理论计算研究表明,Al原子在异质结界面的扩散在离子注入过程中已基本完成,而热退火作用主要是去除无辐射复合中心. 关键词: 量子阱 离子注入 光致荧光谱 界面混合  相似文献   
8.
We report the application of electronic-resonance-enhanced coherent anti-Stokes Raman scattering (ERE-CARS) for measurements of nitric oxide concentration ([NO]) in three different atmospheric pressure flames. Visible pump (532 nm) and Stokes (591 nm) beams are used to probe the Q-branch of the Raman transition. A significant resonance enhancement is obtained by tuning an ultraviolet probe beam (236 nm) into resonance with specific rotational transitions in the (v’=0, v”=1) vibrational band of the A2Σ+–X2Π electronic system of NO. ERE-CARS spectra are recorded at various heights within a hydrogen-air flame producing relatively low concentrations of NO over a Hencken burner. Good agreement is obtained between NO ERE-CARS measurements and the results of flame computations using UNICORN, a two-dimensional flame code. Excellent agreement between measured and calculated NO spectra is also obtained when using a modified version of the Sandia CARSFT code for heavily sooting acetylene-air flames (φ=0.8 to φ=1.6) on the same Hencken burner. Finally, NO concentration profiles are measured using ERE-CARS in a laminar, counter-flow, non-premixed hydrogen-air flame. Spectral scans are recorded by probing the Q1 (9.5), Q1 (13.5) and Q1 (17.5) Raman transitions. The measured shape of the [NO] profile is in good agreement with that predicted using the OPPDIF code, even without correcting for collisional effects. These comparisons between [NO] measurements and predictions establish the utility of ERE-CARS for detection of NO in flames with large temperature and concentration gradients as well as in sooting environments. PACS 07.88.+y; 42.62.Fi; 42.65.Dr  相似文献   
9.
Recently, the semiconductor saturable absorber mirror (SESAM) has become a key component of passive mode-locked solid-state lasers. Here we present a simple method based on the reflection Z-scan technique to measure the key optical parameters of SESAM such as saturation fluence and modulation depth. The experimental results demonstrate that our method is able to perform with a high accuracy of 10−4 and a dynamic range of over four orders of magnitude.  相似文献   
10.
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   
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