不饱和类锗烯H_2CGeNaBr的密度泛函理论研究

应用密度泛函理论DFT方法,在B3LYP/6-311G(d,p)水平上研究了不饱和类锗烯H2CGeNaBr的结构及异构化反应.结果表明,不饱和类锗烯H2CGeNaBr有3种平衡构型,其中非平面的p-配合物型构型能量最低,是其存在的主要构型.并对平衡构型间异构化反应的过渡态进行了计算,求得了转化势垒,预言了最稳定构型的振动频率和红外强度.     

Enzyme-conjugated hybridization chain reaction for magneto-controlled immunoassay of squamous cell carcinoma antigen with pH meter

A nanoparticle-based potentiometric immunoassay was designed for the sensitive detection of squamous cell carcinoma antigen (SCCA; cervical carcinoma marker) on a portable pH meter coupling enzyme-labeled hybridization chain reaction (HCR) with two alternating hairpin DNA probes for the signal amplification. Initially, a sandwich-type immunoreaction was carried out between anti-SCCA capture antibody-conjugated magnetic bead and detection antibody/initiator strand-coated gold nanoparticle (AuNP). Then, the HCR reaction was readily executed between two glucose oxidase (GOx)-labeled hairpins through the initiator strand to form numerous GOx concatamers on the AuNP via the long nicked double-helix. The concatenated GOx oxidized glucose into gluconic acid and hydrogen peroxide, thus resulting in the pH change of the detection solution on a handheld pH meter. Several labeling protocols including GOx-antibody, GOx-AuNP-antibody and GOx-HCR-AuNP-antibody were investigated for detection of target SCCA, and improved analytical features were obtained with the immune-HCR assay. Under optimum conditions, the immune-HCR assay exhibited good pH responses for the determination of SCCA at a concentration as low as 5.7 pg/mL. Additionally, the immune-HCR assay had good precision and reproducibility, high specificity, and acceptable accuracy for analyzing human serum specimens.     

吡啶并[1,4]噁嗪衍生物的合成新方法--酰胺溴代吡啶的分子内偶联

描述了一个方便制备吡啶并1，4-噁嗪衍生物的合成新方法，该法通过分子内偶联构建了噁嗪环系统。     

CARBONIUM CYCLIZATION-STUDIES ON LIGNANS CONTAINING THE DIBENZOCYCLOOCTADIENE SYSTEM.Ⅰ

Schisandrin(1)under the Ritter reaction conditions (conc.H₂SO₄/CH₃CN)gave trace amounts of the expected acetamido derivatives(2 a, 2 b).The main product is 5 a, from intramolecular car-bonium cyclization.     

以学生为中心探讨大学化学与高中化学教育的衔接——无机化学主题

基于阶段教育理论，通过调研大学一年级学生高中化学以及大学无机化学的学习情况，归纳高中化学和大学无机化学的联系与差别，了解学生学习的难点，把握教与学的关系，以学生发展为中心，结合实际教学情况探讨大学无机化学与高中化学的有效衔接问题，为大学无机化学课程教师开展教学工作提供依据和建议。     

LOW-TEMPERATURE HEAT CAPACITY AND THERMODYNAMIC FUNCTIONS OF 2-CHLORO-6-(TRICHLOROMETHYL)PYRIDINE

The heat capacity of 2- chloro- 6- (trichloromethyl)pyridine has heen measured with anadiabatic calorimeter in the range from 13 to 316K. There is no indication of any phasetransition or thermal anomaly in this temperature region for the present compound. Theresults have been compared with those reported in [1] in the overlapping temperaturerange. The experimental heat capacity data have been fitted to a smoothed curve by the aidof the effective frequency distribution method, and the heat capacities below 13K have beenobtained by extrapolating the fitting curve down to 0K. The standard molar thermodynamicfunctions between 0 and 400 K have been derived by combining the present heat capacitymeasurements with the previous ones. The values of C_p~o (T), S~o(T) - S~o(0), [H~o(T) -H~o(0)]/T, and - [G~o(T) - H~o(0)]/T at T = 298.15 K are 189.35, 244.60, 112 .45 and 132.15J·K~(-1)·mol~(-1), respectively.     

LOW-TEMPERATURE HEAT CAPACITIES AND THERMODYNAMIC PROPERTIES OF LANTHANUM AND CERIUM TRIISOTHIOCYANATE HYDRATESI (Ⅰ)——La(NCS)_3, 7H_2O AND Ce(NCS)_3. 7H_2O

The heat capacities of La(NCS)_3. 7H_2O and Ce(NCS)_3. 7H_2O have been measured from 13 to 300K with a fully-automated adiabatic calorimeter. The construction and procedures of the calorimetric system are described in detail. No obvious thermal anomaly was observed for both compounds in the experimental temperature range. The polynomial equations for calculating the heat capacity values of the two compounds in the range 13—300K were obtained by the least-squares fitting based on the experimental C_p data. The C_p values below 13K were estimated by using the Debye and Einstein heat Capacity functions. The standard molar thermodynamic functions were calculated from 0 to 300K. Gibbs energies of formation were also calculated.     

热动力学方法的研究(Ⅱ)——流动混合法的理论和方法

通过对流动体系物理模型的分析，推导出在ＬＫＢ２２７７生物活性检测仪上，采用流动混合方式进样条件下适用的热功率与流速关系，并用计算机回归分析处理，同时求出反应的反应焓变和速率常数．将此方法运用于乙酸乙酯的皂化反应，得到了满意的结果．     

卤代羰基叶立德:“推-拉”稳定作用对四苯基环戊二烯酮与卡宾的脱氧反应的影响(英文)

研究了四苯基环戊二烯酮与三溴甲基苯基汞（二溴卡宾的前体化合物）的卡宾反应，发现该反应可给出比通常有立体障碍的酮要高得多的脱氧（以脱CO的形式）产率．本文从羰基叶立德中间体的“推-拉”稳定作用以及该中间体的构象和电子分布的角度出发，并结合产物分析对这一反常现象进行了讨论，发现在潜芳香结构的羰基化合物与二卤卡宾的反应中，有可能由于“推-拉”作用形成具有芳香结构的羰基是中间体，该中间体由于正负电荷及以较好的分散以及其接近0°／90°型的构象，有效地阻碍了分子间环加成和分子内电环化这两个竞争反应的进行，从而使脱氧途径成为该反应的主渠道．本项研究进一步揭示了一些尚未被人了解的反应规律，合理地解释了反应机理．     

Crystal structures of the complexes of rare earth picrates with N, N, N'''', N''''-tetraphenyl-3, 6-dioxaoctanediamide

The complexes of rare earth picrate with N,N,N',N'-tetraphenyl-3,6-dioxaoctanediamide(TDD),Eu(picc(TDD)] 2CH3CN and [ Y(pic)3(TDD)],have been synthesized.The crystal structures reveal that TDD at is as n tetradentate ligand,forming a ring-like coordination structure with its oxygen atoms together with one oxygen atom of the bidentate pterate In the Eu(Ⅲ) complex,the europium ion with a larger ionic radius lies out of the ring,while in the Y(Ⅲ) complex,the yttrium ion with a smaller ionic radius enters the cavity of the ligand.The structures of the complexes are greatly affected by the ionic radii due to participation of the picrates in coordination.