液相色谱-电喷雾离子阱质谱法测定贝类中软骨藻酸

记忆缺失性贝类毒素(amnesicshellfishtoxin,简称.ASP)主要成分软骨藻酸(domoicacid,简称DA)是一种氨基酸类的生理活性物质(图1),因最早从红藻属的树枝软骨藻(chondriaarmata)分离出来而被命名为软骨藻酸。自1987年加拿大首次发生集体贝类食品中毒事件后,人们从赤潮藻类中的硅藻属(diatom)的多列尖刺菱形藻(nitzschpungensf.multiseries)中检测到了DA,随后,美国、加拿大、北欧一些国家,澳大利亚、日本等国先后从紫贻贝(myltilusedulis)、扇贝(pectenmaximus)、文蛤(callistachione)等贝类体内以及鲭鱼和石蟹的内脏中检测到了DA。鱼、贝通过滤食毒藻,将DA富积在体内,人类因食用被DA污染的鱼、贝而中毒,中毒症状包括恶心、呕吐、腹痛、腹泻等,同时有晕眩、     

New competitive enzyme-linked immunosorbent assay for determination of metallothionein in tissue and sera

A method for the determination of non-ionic surfactants (NS) in the presence of an excess of hydrocarbons is developed. The modified BiAS procedure combined with the indirect tensammetric method (BiAS-ITM) is applied for this purpose. The method consists of extraction of NS into ethyl acetate, precipitation of ethoxylates with modified Dragendorff reagent, removal of adsorbed hydrocarbons by washing with isooctane and the determination of NS in the dissolved precipitate by the ITM. The method is characterised by 96-100% recovery and RSD of 0.02-0.04 at a 1000-fold excess of hydrocarbons. The detection limit of the procedure is 1.5 mug and the linear dynamic range is 2-20 mug in the sample, which facilitates work within the range of 2-1000 mug through the use of aliquots. The non-modified version of the BiAS-ITM exhibits a loss of NS due to their extraction by droplets of residual hydrocarbons trapped in the precipitate. Isooctane as a washing agent is found to be the best among eight tested media: methanol, ethyl acetate, diisopropyl ether, chloroform, water, glacial acetic acid, benzene and isooctane.     

Nachweis und Bestimmung anorganiseher Bestandteile bei Mensch und Tier

Ohne Zusammenfassung     

Mechanistic Study of the Titanocene(III)‐Catalyzed Radical Arylation of Epoxides

An atom‐economical and catalytic arylation of epoxide‐derived radicals is described. The key step of the catalytic system is a sequential electron and proton transfer for the rearomatization of the radical σ‐complex and catalyst regeneration. Kinetic, computational, spectroscopic, and cyclovoltammetric investigations highlight the key issues of the reaction mechanism and catalyst stabilization by collidine hydrochloride. Studies employing radicophiles rule out the participation of cations as reactive intermediates.     

Absorption in the ν3 Band of UF6 Dissolved in Solid Xenon

The ν₃ band of UF₆ isolated in solid xenon is shown to consist of a single sharp spectral feature.     

Ligand functionalization as a deactivation pathway in a fac-Ir(ppy)3-mediated radical addition

Knowledge of the kinetic behavior of catalysts under synthetically relevant conditions is vital for the efficient use of compounds that mediate important transformations regardless of their composition or driving force. In particular, these data are of great importance to add perspective to the growing number of applications of photoactive transition metal complexes. Here we present kinetic, synthetic, and spectroscopic evidence of the mechanistic behavior of fac-Ir(ppy)₃ in a visible light-mediated radical addition to 3-methylindole, demonstrating the instability of fac-Ir(ppy)₃ under these conditions. During the reaction, rapid in situ functionalization of the photocatalyst occurs, eventually leading to deactivation. These findings demonstrate a conceivable deactivation process for catalytic single electron reactions in the presence of radicophilic ligands. Attempts to inhibit photocatalyst deactivation through structural modification provide further insight into catalyst selection for a given system of interest.     

The effect of trip wire roughness on the performance of the Wortmann FX 63-137 airfoil at low Reynolds numbers

An experimental investigation was conducted on the performance and boundary layer characteristics of the Wortmann FX 63-137 airfoil with and without trip wire roughness. Data were obtained through use of a three-component strain gage force balance and static pressure measurement equipment at a test Reynolds number of R _c = 100,000. Emphasis was placed on determining the effect of trip wire placement and size on such performance parameters as (C _l /C _d )_max and (C _l ^3/2 /C _d )_max. Prediction of transition location by the criterion due to Tani and Gibbings was found to have limited application. Most trip wire locations resulted in degraded performance, but for some locations, minimum drag was reduced, maximum lift to drag ratio increased, and hysteresis averted.     

Integral transform and convolution of analytic functionals on abstract Wiener space

Yeh defined a convolution of functionals on classical Wiener space and investigated the relationship between the Fourier-Wiener transforms of functionals in certain classes and the Fourier-Wiener transform of their convolution. Yoo extended Yeh's results to abstract Wiener space. In this paper, we introduce the intergal transform and convolution of analytic functionals on abstract Wiener space. And we establish the relationship between the integral transforms of exponential type of analytic functionals and the integral transform of theor convolution. Also we obtain Parseval's and Plancherel's relations for those functionals from this relationship. The main results of Yeh and Yoo then follow from our results as corollaries.     

Crystal structure and spectroscopic elucidation of 3-phenylpyridinium hydrogensquarate

The novel 3-phenylpyridinium hydrogensquarate (1) has been synthesized and its structure and properties are elucidated spectroscopically, thermally and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy, TGA, DSC, DTA and ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and electronic spectrum. 3-Phenylpyridinium hydrogensquarate, crystallizes in the space group P?1 and the ions in the unit cell are joined into layers by intermolecular NH?OC_(Sq) bonds with bond lengths of 2.625 and 2.626 Å, respectively. Hydrogentartarates form dimers by strong OCOH?OCO interactions (2.499 Å).     

A mathematical approach to the study of the United States Code

The United States Code (Code) is a document containing over 22 million words that represents a large and important source of Federal statutory law. Scholars and policy advocates often discuss the direction and magnitude of changes in various aspects of the Code. However, few have mathematically formalized the notions behind these discussions or directly measured the resulting representations. This paper addresses the current state of the literature in two ways. First, we formalize a representation of the United States Code as the union of a hierarchical network and a citation network over vertices containing the language of the Code. This representation reflects the fact that the Code is a hierarchically organized document containing language and explicit citations between provisions. Second, we use this formalization to measure aspects of the Code as codified in October 2008, November 2009, and March 2010. These measurements allow for a characterization of the actual changes in the Code over time. Our findings indicate that in the recent past, the Code has grown in its amount of structure, interdependence, and language.