锰(Ⅱ)催化氧化1，5-二(2-羟基-5-磺酸基苯)-3-氰基甲动力学及其应用

建立了一种测定痕量锰的新方法,并对反应的最佳条件、动力学参数及反应机理进行探讨,建立了反应动力学方程。方法测定 Mn(Ⅱ)范围 0.00～1.00 ng/mL,检出限 8.5×10-12 g/mL。方法可用于一次蒸馏水和井水中痕量锰的测定。     

超级铝热剂Al/CuO前驱体的制备、表征、热分解机理及非等温分解反应动力学

以硝酸铜、无水乙醇、1,2-环氧丙烷和纳米铝粉为原料, 在超声振荡条件下, 采用溶胶-凝胶法制备了纳米复合含能材料——超级铝热剂Al/CuO的前驱体. 利用热重-差示扫描量热-傅里叶变换红外-质谱(TG- DSC-FTIR-MS)联用技术, 研究了纳米Al/CuO溶胶-凝胶前驱体的热行为和分解过程及机理. 利用不同升温速率下的TG-DTG分析, 研究了纳米超级铝热剂Al/CuO的溶胶-凝胶前驱体的热分解反应机理, 采用了6种动力学分析方法进行动力学参数计算, 得到前驱体分解反应的表观活化能、反应级数、频率因子等动力学参数, 纳米Al/CuO前驱体分解反应的动力学方程为: dα/dt=10^14.0×4α^3/4exp(-2.0×10⁴/T).     

铑(Ⅰ)催化有机汞化合物偶联反应机理的研究

研究了β-氯化萘汞在[CIRh(CO)₂]₂催化下于六甲基磷酰胺溶液中的偶联反应动力学,证明其反应为二级,求得了偶联反应动力学常数.α-氯化萘汞和α-溴汞代苯乙酸乙酯在相同的反应条件下不发生偶联反应;在α一溴汞代苯乙酸乙酯的偶联反应条件下分离和鉴定了有机铑(I)中间体,根据所提出的反应机理,对上述现象进行了讨论.     

Co(II)Schiff碱配合物的合成、氧合反应热力学及热分解动力学的研究

合成了两种新的钴(II)schiff碱配合物水杨醛L-甲硫氨酸-水合钴(II)(1), 邻香兰素L-甲硫氨酸-水合钴(II)(2)。通过元素分析、红外光谱、热分析等测试手段研究了配合物的性质, 并确定了配合物的组成。用气体吸收装置测定配合物在乙腈溶液中不同温度下的饱和吸氧量, 求得氧合反应的平衡常数及热力学参数, 同时探讨了温度和配体结构对配合物氧合性能的影响。用TG-DTG法研究了配合物的热稳定性及非等温热分解动力学, 并采用积分法和微分法相结合的方法,推断了两种配合物的第一步热分解反应机理, 得到了热分解反应动力学参数及其动力学方程。     

Co(II)Schiff碱配合物的合成、氧合反应热力学及热分解动力学的研究

合成了两种新的钴(II)schiff碱配合物水杨醛L-甲硫氨酸-水合钴(II)(1), 邻香兰素L-甲硫氨酸-水合钴(II)(2)。通过元素分析、红外光谱、热分析等测试手段研究了配合物的性质, 并确定了配合物的组成。用气体吸收装置测定配合物在乙腈溶液中不同温度下的饱和吸氧量, 求得氧合反应的平衡常数及热力学参数, 同时探讨了温度和配体结构对配合物氧合性能的影响。用TG-DTG法研究了配合物的热稳定性及非等温热分解动力学, 并采用积分法和微分法相结合的方法,推断了两种配合物的第一步热分解反应机理, 得到了热分解反应动力学参数及其动力学方程。     

铁(Ⅲ)离子在ATP与去铁转铁蛋白之间交换动力学的研究

使用分光光度法研究了Fe(Ⅲ)离子在去铁转铁蛋白(apoTf)与ATP之间的交换动力学,得到反应的动力学参数及反应速率表达式,并提出了反应机理。     

铁(Ⅲ)离子在ATP与去铁转铁蛋白之间交换动力学的研究

使用分光光度法研究了Fe(Ⅲ)离子在去铁转铁蛋白(apoTf)与ATP之间的交换动力学,得到反应的动力学参数及反应速率表达式,并提出了反应机理。     

固态硫酸锂一水合物脱水过程的非等温动力学

采用TG DTG技术研究了固态硫酸锂一水合物脱水过程 ,运用Malek等提出的热分析动力学数据处理方法 ,确定了脱水过程的动力学机理模式f(α)为n(1-α) [-ln(1-α) ]1 - 1 n或为αm(1-α) n,并求得相应动力学参数。     

钴(Ⅱ)催化过氧化氢氧化5-Br-TAMB的褪色反应动力学及其应用

研究了NaAc-HAc介质中钴(Ⅱ)催化H_2O_2氧化5-Br-TAMB的褪色的反应,测定了反应动力学参数,探讨了反应机理,并建立了测定痕量钴的新方法。本法检出限为1.8×10~(-10)g/mL,钴(Ⅱ)浓度在0～124.7 ng/12.5 mL范围内与1g(A_0/A)呈良好的线性关系。该体系已用于人发、茶叶中钴的测定,结果满意。     

典型聚乙烯、聚丙烯、聚苯乙烯废塑料共热解初期反应特性的ReaxFF分子模拟研究

利用反应力场分子模拟(ReaxFF MD)结合反应机理自分析(AutoRMA)工具,从动力学、热解产物及热解反应过程三方面在原子层面上,探究了典型聚乙烯(PE)、聚丙烯(PP)、聚苯乙烯(PS)废塑料共热解的反应机理.结果表明,PE/PP/PS共热解的动力学参数可通过C–C键和C–H键断裂的活化能加权求和(即Char ...     

STRUCTURE,STEREOCHEMISTRY, AND MECHANISM OF FORMATION OF N-ACYLSULFILIMINES

Abstract

The methods for the preparation of sulfilimines are summarized, and the stereochemistry and electronic structure of N-acylsulfilmines are discussed. Sulfilimines have a non-planar structure, but the S^IV[sbnd]N bond character cannot be determined from their resolvability. N-Sulfonylsulfilimines (RR'SNSO₂Q) contain a delocalized S^IVNS^VI d bond system, the S^IVN and S^VIn bonds are of intermediate bond order. S^IV[sbnd]CH₃ hyperconjugation causes strong bond shortening. An asymmetric conformation of a sulfilimine containing two identical S^IV substituents was found in the crystalline state which could be accounted for theoretically. The rotation of the SN bond is not restricted in solution. The structure of N-carboacylsulfilimines (RR'SNCOQ) is strongly polar due to the strong NCO conjugation, and the instability of these compounds can be ascribed to the polar structure. The reaction between thioethers and chloramine-T is a nucleophilic substitution; the rate of the reaction is influenced by the nucleophilic character of the thioether sulfur atom. Thioether carboxylic acids are usually oxidized by chloramine-T and only give a sulfilimine if the carboxyl group is fixed sufficiently distant from the sulfur atom. The formation of sulfilimines from an optically active sulfoxide by the action of a sulfonamide (or N-sulfinylsulfonamide) proceeds via a trigonal bipyramidal intermediate with complete inversion. The intermediate of the sulfilimine synthesis starting from arylsulfonyl azides is a sulfonyl imene.     

煤中砷,铅,铍,铬等元素的存在状态

煤是由有机物和无机物组成的混合物。无机物按其在煤中的浓度大小可分为三类:(1)常量元素,在煤中浓度大于0.5%,如Si,Al,Fe,Ca等。(2)次要元素,约占煤的0.02%—.5%,包括K,Mg,Na,Ti,有时还有P,Ba等。(3)微量元素,在煤中浓度<0.02%,这类元素目前已测出60种左右。60年代以来,基于能源需求的增加,国内外煤炭消耗量都很大,考虑到有害的微量元素对环境的污染,国外进行了大量的煤     

关于二元酸与二元醇的聚酯反应和酯化与水解反应动力学

关于二元酸与二元醇的聚酯反应动力学,Flory和等人都会做过研究,唐敖庆等在较广泛的实验基础上提出氢离子催化机理及其动力学.酯化机理为:     

THERMOCHEMISTRY OF HETEROATOMIC COMPOUNDS,XX. THEORETICAL CALCULATIONS OF THE VAPORIZATION ENTHALPIES OF ALKYLARSINES,STIBINES, AND BISMUTHINES

The vaporization enthalpies (ΔH _vap ) of 26 primary, secondary, and tertiary alkylarsines, stibines, and bismuthines were calculated using the Trouton and Wadso equations and the first-order topological solvation index, ¹ χ ^S . The contributions to vaporization enthalpy for ─AsH ₂ (16.6 ± 0.2), > AsH (16.7 ± 0.1) groups and As(III)-atom in R ₃ As (13.7 ± 1.0), ─SbH ₂ (22.0 ± [2.0]), > SbH (19.0 ± [2.0]) groups and Sb(III)-atom in R ₃ Sb (12.7 ± 3.5), ─BiH ₂ (26.3 ± [2.2]), > BiH (24.3 ± [2.2]) groups and Bi(III)-atom in R ₃ Bi (16.2 ± 3.1 kJ mol^?1 ) were calculated.     

MAGNETOSTRATIGRAPHY OF PERMO-TRIASSIC BOUNDARY SECTION OF MEISHAN OF CHANGXING,ZHEJIANG

A hundred and eleven samples were collected from the Permian-Triassic boundarysection of Meishan (31.1°N, 119.7°E) which includes the Changxing Formation of thelate Permian and the Qinglong Formation of early Triassic. The thickness of the sectionis about 60 m. Paleomagnetic results indicate that six normal and reversed polarity zoneswere recorded in the section which all belong to the Illawarra mixed interval. Theboundary of Permo-Triassic lies at 1.2 m (or 2.7 m) above the bottom of normal polarityzone V. The magnetic minerals in the rocks of the lower part of the Changxing Forma-tion mainly are goethite, haematite and titaniferous magnetite while in the upper part ofthe formation are chiefly titanomagnetite and magnetite, goethite is secondary. Magne-tite and haematite as the main magnetic minerals were included in marl and mudstone ofthe Qinglong Formation. Based on the results of the magnetically stable samples thepaleopole position of 50.7°N, 230.3°E was obtained, meanwhile, the paleolatitude     

PHOTOSENSORY BEHAVIOR OF A BACTERIORHODOPSIN-DEFICIENT MUTANT, ET-15, OF Halobacterium halobium

– Halobacterium halobium , strain ET-15, which does not contain detectable amounts of bacteriorhodopsin (BR) shows behavioral responses to UV and yellow-green light. Attractant stimuli. i.e. light-increases in the yellow-green range or light-decreases in the UV, suppress the spontaneous reversals of the swimming direction for a certain time. Repellent stimuli, i.e. light-decreases in the yellow-green range or light-increases in the UV, elicit an additional reversal response after a few seconds. Action spectra of both sensory photosystems, PS 370 and PS 565, were measured with attractant as well as with repellent stimuli. As in BR-containing cells, maximal sensitivity was always found at 370 nm for the UV-system and at 565 nm for the long-wavelength system. Fluence-response curves at 370 and 565 nm obtained with strain ET-15 and with a BR-containing strain show that the sensitivity of both photosystems is not reduced in the absence of BR. It is concluded that BR is required neither for PS 565 nor for PS 370. Instead retinal-containing pigments different from BR have to be assumed to mediate photosensory behavior.     

延胡索己素、壬素、癸素和子素的结构鉴定

延胡索(Corydalis turtshnninovii Bess.f.Yanhusuo Y.H.Chou et C.C.Hsü)^*块茎又称元胡,能活血散瘀,利气止痛.药用主要作为镇痛药.赵承嘏^[1]曾从其块茎中分得十三种生物碱,分别命名为延胡索素甲、乙、丙、丁、戊、己、庚、辛、壬、癸、子、丑和寅.其中甲素鉴定为紫堇碱,丙素为普鲁托品,丁素为l-四氢黄连碱,戊素为dl-四氢黄连碱,己素为l-紫堇单酚碱,庚素为d-紫堇球碱,寅素为a-别隐品碱.黄鸣龙^[2]除证明乙素为dl-四氢巴马汀外,还分得黄连碱和去氢紫堇碱.     

A THEORETICAL TREATMENT OF THE SULFUR-CONTAINING ANALOGS OF CYCLOBUTADIENE,CYCLOOCTATETRAENE, BUTALENE,AND OCTALENE

Abstract

Several coordination complexes of cyclobutadiene (I) have been prepared (e.g., cyclobutadiene iron tricarbonyl [1]) and cyclooctatetraene (II) is a well-known compound (for a potentially planar form of cyclooctatetraene, see [2]). Although butalene [3] (III) has not been synthesized so far, octalene (IV) has been obtained by Vogel and co-workers [4,5]. Recently we have carried out a theoretical study of the physical and chemical properties of butalene (III) and octalene (IV), and of the various annelated butalenes and octalenes [6,7] using the HMO and SCF-MO (PPP) quantum-chemical methods as well as the structure-resonance theory and graph theoretical methods. Numerous theoretical data are available in the literature on cyclobutadiene (I) and cyclooctatetraene (II).     

OLEFIN SYNTHESIS USING LITHIUM DERIVATIVES OF N,N,N',N'-TETRAMETHYLDIAMIDES OF ARYLMETHANEPHOSPHONIC ACIDS

Abstract

The reaction of lithium derivatives of N,N,N',N'-tetramethyldiamides of arylmethanephosphonic acids (1-Li) with aldehydes 2 is studied. It is found that under certain reaction conditions (THF, 5 hrs at -70°C and then allowing to warm to room temperature) the aldol stage of the reaction is highly stereoselective, only erythro adducts (2-hydroxyphosphonamides) 3, 4 being formed in 47–75% yields. By heating of 3 and 4 in neutral medium the corresponding (Z)-olefins 5, 6 are obtained (yields 64–74%). It is established that an acid catalyzed olefination of 2-hydroxyphosphonamides is also possible, but the reaction is not stereospecific.