介质对配合物稳定性的影响——Ⅱ.Cu(SCN)+—NaNO3—二氧六环—水体系

本文用分光光度法确定了25℃时配阳离子Cu(SCN)~+在NaNO_3—二氧六环—H_2O介质中的稳定常数。溶剂组成变化范围为0,5,10,15和20wt％二氧六环,离子强度范围为0.2～3.0moledm~(-3),溶液的pH=1.5～1.6。本文提出了基于Pitzer方程式的最小二乘多项式逼近法,确定出各种不同组成混合溶剂中配合物的热力学稳定常数。讨论了该常数和一级介质效应与溶剂组成和介电常数的关系。     

Novel synthesis of photochromic polymers via ROMP

[reaction: see text] Ring-opening metathesis polymerization (ROMP) of a photochromic 1, 2-bis(3-thienyl)cyclopentene monomer generated a series of novel polymers. All polymers exhibit reversible light-activated interconversion between their colorless-open and their colored-closed forms.     

邻苯二酚紫退色光度法测定微量锰(Ⅱ)

在硫酸介质中．高锰酸根氧化邻苯二酚紫使其退色，退色程度在一定范围内与高锰酸根加入量成良好的线性关系。据此建立了一种测定微量锰（Ⅱ）的新方法。最大吸收波长λmax＝550nm，表观摩尔吸光系数ε＝4．2×104L·mol-1·cm－1·。锰（Ⅱ）量在0－0．8mg／L范围内符合比耳定律．方法应用于求和面粉中微量锰（Ⅱ）的测定，结果满意。     

2，6－双（1′－苯基－3′－甲基－5′－氧代－4′－甲酰吡唑）吡啶稀土配合物的合成与表征

在乙醇－水溶液中合成了１４种２，６－双（１′－苯基－３′－甲基－５＇－氧代－４＇－甲酰吡唑）吡啶稀土配合物。元素分析确定其化学组成为ＲＥ＿２Ｌ＿３·ｎＨ＿２Ｏ，并用紫外可见光谱、红外光谱、核磁共振谱、热分析、荧光光谱、摩尔电导等进行了表征。     

Fe（Ⅲ）－TEA－5－Br－PADAP－H_2O_2体系中催化波的研究及其应

在０．２ｍｏｌ·Ｌ￣（－１）ＮＨ＿４Ｃｌ－ＮＨ＿３·Ｈ＿２Ｏ底液中，（ｐＨ为９．２６），得到一个极为灵敏的Ｆｅ（Ⅲ）－ＴＥＡ－５－Ｂｒ－ＰＡＤＡＰ－Ｈ＿２Ｏ＿２配合吸附催化波，其峰电位为－０．７１Ｖ（ｖｓ．ＳＣＥ）。铁浓度在１．８×１０￣（－１０）～５．４×１０￣（－６）ｍｏｌ·Ｌ￣（－１）范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究，证明是一种配合吸附催化波，并成功地应用于各类水样，钒催化剂中微量或痕量铁的测定。     

Determination of catechol derivatives on pretreatment and copolymer coated glassy carbon electrode

A glassy carbon electrode was pretreated electrochemically and was coated with a copolymer of maleic acid anhydride attached with Eastman-AQ55D (MA/AQ). The voltammetric behavior of a series of biologically important compounds, such as dopamine, L-DOPA, DOPAC, ascorbic acid and uric acid were examined at both pretreated and coated electrodes. Electrochemical pretreatment increased peak current of dopamine and L-DOPA while decreased that of ascorbic acid, uric acid and DOPAC. The copolymer coating caused a decrease of peak currents, but effectively hindered the anionic species (ascorbic acid, uric acid and DOPAC) access to the electrode surface. In flow injection and liquid chromatographic analysis. The dopamine and L-DOPA yielded the better selectivity response at MA/AQ electrode than at bare and AQ electrodes.     

Octasilsesquioxane Chemistry II. Hydrosilylation Reaction of Octa(hydrido)silsesquioxane with Unsaturated Substrates and Product Properties

The hydrosilylation reaction of octa(hydrido)silsesquioxane with ω‐halo‐1‐alkenes and other unsaturated substrates allows attachment of 8 long‐chain functionalized alkyls on the cubic Si₈O₁₂ skeleton. Pt/C and H₂PtCl₆ have been adopted as the catalysts, the yields being 74–98% for compounds 2–9 . For terminal alkenes, the hydrosilylation follows the anti‐Markonikov's rule. The morphological state of 2–9 ranges from viscous liquid to crystalline materials. The pyrolysis results indicate that 7 , a material of hard spherical core and soft flexible shell, may likely act as nanometer‐size ball bearings up to more than 400 °C. The X‐ray structure of 9 reveals that the molecule is required to possess a center of symmetry crystallographically. The linear arms on 9 , except for two of them, are virtually all‐trans in conformation, not counting the ω‐C‐Cl bond.     

硝酸肼的量热研究

用精密自动绝热量热计测定了在220 K—370 K温度范围内硝酸肼的热容、熔化热、熔化温度和熔化熵。所得热容数据的精密度以百分偏差的均方根值表示为±0.2％。三次熔化热测定的相对偏差为±0.1％。为验证结果的可靠性, 用该装置测定了冰的熔化热和熔化温度, 其结果与文献值一致; 又用法国SETARAM公司的高温量热计测定了硝酸肼的熔化热和熔化温度, 其结果与我们用量热法测定的结果一致; 从量热结果计算出了该试样的纯度, 该结果亦与化学分析的结果一致。这些均可说明我们所测得的数据是可靠的。     

反气相色谱法研究聚丙烯结晶动力学及对熔点和结晶度的测定

<正> 研究聚合物的结晶动力学,过去大多采用膨胀计法和解偏振光法。曾有文献报道采用反气相色谱法测得聚乙烯等温结晶线。通过实验可知,测定聚丙烯结晶度时,试样热历史和测定前陈化温度的选择均影响测定结果。此外在测定聚丙烯试样的熔点时,保留图中出现了两个转折,经反复实验证实:此两转折对应于聚丙烯中不同晶形(α-、β-形)的熔点。     

工业原料铁制备浆态床FT合成用的Fe-Cu-K-Si催化剂的探索

费托合成技术是公认的将煤基合成气转化为液体燃料和化工原料的重要技术途径。虽然固定床费托合成技术从五十年代起已经工业运转，但是浆态床费托合成技术由于其传热性能好，可直接使用第二代气化炉生产的富CO合成气，反应器结构简单，单台反应器生产能力大，开工率高，产品结构合理，