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961.
偏最小二乘法分析非线性加和的多组分体系   总被引:7,自引:3,他引:7  
倪永年 《分析化学》1990,18(4):344-347
  相似文献   
962.
采用两步溶胶-凝胶过程制备了含铕的三元配合物的凝胶。荧光激发光谱证实于SiO2基质中原位合成了铕的配合物。含铕配合物的杂化材料发出铕的特征荧光,与相应的纯配合物溶于乙醇相比,铕离子具有较长的荧光寿命。  相似文献   
963.
Linear copolymers from N-isopropylacrylamide(NIPA),acrylic acid(AA)and diacetone acrylamide(DAA)have been prepared. The effect of composition,ionic strength and pH on their lower critical solution temperature(LCST)has been investigated.  相似文献   
964.
965.
The studies of the Bulung Boni and Bulung Anggur (Caulerpa spp.) species and secondary metabolites are still very limited. Proper identification will support various aspects, such as cultivation, utilization, and economic interests. Moreover, understanding the secondary metabolites will assist in developing algae-based products. This study aimed to identify these indigenous Caulerpa algae and analyze their bioactive components. The tufA sequence was employed as a molecular marker in DNA barcoding, and its bioactive components were identified using the GC-MS method. The phylogenetic tree was generated in MEGA 11 using the maximum likelihood method, and the robustness of the tree was evaluated using bootstrapping with 1000 replicates. This study revealed that Bulung Boni is strongly connected to Caulerpa cylindracea. However, Bulung Anggur shows no close relationship to other Caulerpa species. GC-MS analysis of ethanolic extracts of Bulung Boni and Bulung Anggur showed the presence of 11 and 13 compounds, respectively. The majority of the compounds found in these algae have been shown to possess biological properties, such as antioxidant, antibacterial, anticancer, anti-inflammation, and antidiabetic. Further study is necessary to compare the data obtained using different molecular markers in DNA barcoding, and to elucidate other undisclosed compounds in these Caulerpa algae.  相似文献   
966.
非简谐振子与新条件精确可解势   总被引:2,自引:0,他引:2  
马涛  倪致祥 《中国物理 C》1999,23(7):650-654
利用超对称性,由平移的非简谐振子构造出了多类新的条件精确可解势,并得到相应的非线性谱生成代数.  相似文献   
967.
对一系列杂环双齿配体--4,7-二苯邻菲绕啉、5-硝基邻菲绕啉、2,9-二甲基邻菲绕啉、2,9-二甲基-4,7-二苯邻菲绕啉和α,α'-联喹啉(以下均用L表示)与CCl3COO-和15种正三价稀土离子形成的三元络合物在水-氯仿间的革取行为进行了研究。发现在这些体系中,都存在明显的“四分组效应”,且稀土的萃取率随介质pH而变化。井讨论了L的分子量及结构对稀土萃取的影响。  相似文献   
968.
In this paper, we first elaborate on the effects of surface plasmon (SP) coupling on the modulation responses of the emission of a light-emitting diode (LED) and its down-converted lights through colloidal quantum dots (QDs). The results of our past efforts for this subject are briefly discussed. The discussions lay the foundation for the presentation of the new experimental data of such down-converted lights in this paper. In particular, the enhancement of the modulation bandwidth (MB) of a QD-based converted light through SP coupling is demonstrated. By linking green-emitting QDs (GQDs) and/or red-emitting QDs (RQDs) with synthesized Ag nano-plates via surface modifications and placing them on a blue-emitting LED, the MBs of the converted green and red emissions are significantly increased through the induced SP coupling of the Ag nano-plates. When both GQD and RQD exist and are closely spaced in a sample, the energy transfer processes of emission-reabsorption and Förster resonance energy transfer from GQD into RQD occur, leading to the increase (decrease) in the MB of green (red) light. With SP coupling, the MB of a mixed light is significantly enhanced.  相似文献   
969.
Ionic liquids (ILs) have a wide range of applications, owing to their negligible vapor pressure, high electrical conductivity, and low melting point. However, the thermal hazards of ILs and their mixtures are also non-negligible. In this study, the thermal hazards of various binary imidazolium ionic liquids (BIIL) mixtures were investigated. The effects of parent salt components and molar ratios on the thermal decomposition temperature (Td) and flashpoint temperature (Tf) are investigated. It is found that both Td and Tf increase as the proportion of highly thermally stable components in BIIL mixtures increases. Furthermore, the decomposition process of BIIL mixtures can be divided into two stages. For most molar ratios, the Tf of the BIIL mixtures is in the first stage of thermal decomposition. When the proportion of highly thermally stable components is relatively high, Tf is in the second stage of thermal decomposition. The flammability is attributed to the produced combustible gases during the thermal decomposition process. This work would be reasonably expected to provide some guidance for the safety design and application of IL mixtures for engineering.  相似文献   
970.
In several previous studies, it was reported that a supported pipe with small geometric imperfections would lose stability when the internal flow velocity became sufficiently high. Recently, however, it has become clear that this conclusion may be at best incomplete. A reevaluation of the problem is undertaken here by essentially considering the flow-induced static deformation of a pipe. With the aid of the absolute nodal coordinate formulation(ANCF) and the extended Lagrange equations for dynam...  相似文献   
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