Analyses without calibration curve for determination of indium in sediment and geochemical samples

Influences of atomization temperatures on the characteristic mass and the atomic absorption coefficient of indium were studied. The results show that the values of characteristic mass obtained from the wall, using the platform and the V-shaped boat have appeared to be stable to better than 10, 6 and 12% in the range of 1600–2400 °C, respectively. The determination of indium without calibration curve by furnace with the V-shaped boat using palladium and ammonium salt of EDTA as a matrix modifier are described. The proposed method was applied to the determination of indium in standard sediment and geochemical reference samples and satisfactory results were obtained.     

Tb^3＋配合物的电子振动光谱研究

采用时间分辨荧光光谱系统测量了几种稀土Ｔｂ３＋配合物的＾７Ｆ６－＾５Ｄ４电子跃迁的激发光谱，同时测量了与该跃迁及配合物中配位基团的相关的电子振动光谱。结合电子振动跃迁的理论分析，研究了这些电子振动光谱的强度和位置的特征。及其与Ｔｂ＾３＋周围配位情况的关系，表明电子振动光谱有可能用作稀土在其梧合物或在生物分子中结合位置的微结构光谱探针。     

Synthesis and crystal structure of nickel(Ⅱ) and zinc(Ⅱ) complexes with 2,4-bis(3,5-dimethylpyrazol-1-yl)-6-methoxyl-1,3,5-triazine

2,4-Bis(3,5-dimethylpyrazol-1-yl)-6-methoxyl-1,3,5-triazine(bpt) has been synthesized by using a new, simple and general method with high yields. Reactions of bpt with Ni(CIO4)2 · 6H2O and Zn(CIO4)2 · 6H2O in methanol gave mononuclear complex [Ni(bpt)2] · (CIO4)2 · H2O and ternary complex [Zn(mpt)2(dmp)](CIO4)2 respectively, where mpt (2,4-dimethoxy-6-(3,5-dimethyl-pyrazol-1-yl)-1,3,5-triazine) and dmp(3,5-dimethylpyrazole) are the alcoholysis products of bpt in the presence of Zn2+ ion. A possible mechanism for this catalytic reaction was proposed. X-ray crystal structure for ligand bpt, Ni and Zn complexes are reported. The protonated form of the ligand bpt crystallizes as its perchlorate salt including one molecule of water, [Hbpt · H2O · CIO4]. The proton is located on one pyrazole N-atom. [Hbpt ?H2O ?CIO4], in which [Hbpt]+ is in cis-cis conformation, are packed in slipped stacks of approximately parallel layers. The π-π overlap interactions between the non-protonized pyrazoles of the adjace     

Temperature compensating Elinvar character in Fe-Mn-Si alloys

Young's modulus-temperature and thermal expansion curves were measured in γ-Fe-31Mn-(0.25-8.67) Si-0.77C (at%) alloys by dynamic audio resonance method and in a light dilatometer. The results show that the anomalies in Young's modulus and thermal expansion appear near the Néel temperature. The temperature coefficient of Young's modulus, (1/E_p)(dE_p/dT), is controlled by Si content below the Néel temperature. When Si content increases to 5.31 at%, (1/E_p)(dE_p/dT) is close to zero in temperature range from 260 to 335 K, i.e. the Fe-31Mn-5.31Si-0.67C (at%) alloy shows Elinvar character. The temperature range in which the Elinvar character appears is wider than that of γ-Fe-Mn Elinvar alloys. The change in exchange energy and the ΔE effect result from the effect of Si on the antiferromagnetic behavior in γ-Fe-Mn alloys since it induces or enhances localized magnetic moment. When the increase in normal Young's modulus due to lowering temperature is compensated by the ΔE effect caused by the antiferromagnetic ordering, Elinvar character appears.     

Global convergence of serial Boolean networks based on algebraic representation

This paper analyzes the global convergence of serial Boolean networks (SBNs) via the semi-tensor product of matrices, and presents some new results. Firstly, an algebraic representation is obtained for SBNs, and an algorithm is established for the conversion between the algebraic representations of SBNs and the corresponding Boolean networks. Secondly, the non-equivalence of global convergence between SBNs and the corresponding Boolean networks is revealed, although they have the same fixed points. Thirdly, a necessary and sufficient condition is presented for the global convergence of SBNs. Finally, the obtained results are applied to the evolutionary behaviour analysis of evolutionary networked games with cascading myopic best response adjustment.     

硫酸根型阴离子交换树脂法改善PAC絮凝性能的研究

体系以聚合氯化铝溶液为原料，以硫酸型强碱性阴离子交换树脂为载体，进行离子交换反应。结果表明，在保持氧化铝含量基本不变的情况下，能有效地提高聚合铝的碱化度。同时生成含ＳＯ４＾２－的聚合氯化铝，实验证明它的絮凝效果优于了聚合氯化铝。     

反应性离子交换法合成纳米ZnO及其光催化性能

 以 ZnSO4 和 NaOH 为原料, 强碱性阴离子交换树脂为模板, 采用反应性离子交换法一步合成了高纯纳米 ZnO 晶体, 并运用扫描电子显微镜、X 射线衍射和紫外-可见光谱等技术对样品进行了表征, 初步探讨了合成机理. 结果表明, 制得的纳米 ZnO 晶体呈一维棒状, 它在树脂表面的形成过程与 ZnSO4 的初始浓度密切相关. 该 ZnO 样品对光催化降解甲基橙具有较高的活性和循环使用性能.     

PLS-原子吸收光谱法同时测定稀土氧化物中的Eu和Cu

用偏最小二乘法（ＰＬＳ）校正了火焰原子吸收分析中Ｅｕ３２４．７５３ｎｍ对Ｃｕ３２４．７５４ｎｍ吸收线重叠干扰,用铜空心阴极灯同时测定了合成样及稀土氧化物中的Ｅｕ和Ｃｕ。     

多波长线性回归法校正火焰原子吸收光谱干扰

用多波长线性回归法校正了火焰原子吸收分析中Ｇａ４０３．２９８ｎｍ对Ｍｎ４０３．３０７ｎｍ的吸收线重叠干扰，对合成样中Ｍｎ和Ｇａ含量的测定，结果令人满意。     

DNA-mediated exciton coupling and electron transfer between donor and acceptor stilbenes separated by a variable number of base pairs

The synthesis, steady-state spectroscopy, and transient absorption spectroscopy of DNA conjugates possessing both stilbene electron donor and electron acceptor chromophores are described. These conjugates are proposed to form nicked DNA dumbbell structures in which a stilbenedicarboxamide acceptor and stilbenediether donor are separated by variable numbers of A-T or G-C base pairs. The nick is located either adjacent to one of the chromophores or between two of the bases. Thermal dissociation profiles indicate that stable structures are formed possessing as few as two A-T base pairs. Circular dichroism (CD) spectra in the base pair region are characteristic of B-DNA duplex structures, whereas CD spectra at longer wavelengths display two bands attributed to exciton coupling between the two stilbenes. The sign and intensity of these bands are dependent upon both the distance between the chromophores and the dihedral angle between their transition dipoles [Deltaepsilon approximately Rda(-2) sin(2theta)]. Pulsed laser excitation of the stilbenediamide results in creation of the acceptor-donor radical ion pair, which decays via charge recombination. The dynamics of charge separation and charge recombination display an exponential distance dependence, similar to that observed previously for systems in which guanine serves as the electron donor. Unlike exciton coupling between the stilbenes, there is no apparent dependence of the charge-transfer rates upon the dihedral angle between donor and acceptor stilbenes. The introduction of a single G-C base pair between the donor and acceptor results in a change in the mechanism for charge separation from single step superexchange to hole hopping.