Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

Synthesis and Optical and Redox Properties of Symmetric and Asymmetric BODIPYs

Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

Conformations and steric and stacking interactions of trisubstituted ureas and thioureas with alkyl and phenyl groups

The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R₂UPh type and -thioureas of the R₂TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.     

A configurational and conformational study of aframodial and its diasteriomers via experimental and theoretical VA and VCD spectroscopies

In this work we present the experimental and theoretical vibrational absorption (VA) and the theoretical vibrational circular dichroism (VCD) spectra for aframodial. In addition, we present the theoretical VA and VCD spectra for the diasteriomers of aframodial. Aframodial has four chiral centers and hence has 2⁴ = 16 diasteriomers, which occur in eight pairs of enantiomers. In addition to the four chiral centers, there is an additional chirality due to the helicity of the entire molecule, which we show by presenting 12 configurations of the 5S,8S,9R,10S enantiomer of aframodial. The VCD spectra for the diasteriomers and the 12 configurations of one enantiomer are shown to be very sensitive not only to the local stereochemistry at each chiral center, but in addition, to the helicity of the entire molecule. Here one must be careful in analyzing the signs of the VCD bands due to the ‘non-chiral’ chromophores in the molecule, since one has two contributions; one due to the inherent chirality at the four chiral centers, and one due to the chirality of the side chain groups in specific conformers, that is, its helicity. Theoretical simulations for various levels of theory are compared to the experimental VA recorded to date. The VCD spectra simulations are presented, but no experimental VCD and Raman spectra have been reported to date, though some preliminary VCD measurements have been made in Stephens’ lab in Los Angeles. The flexible side chain is proposed to be responsible for the small size of the VCD spectra of this molecule, even though the chiral part of the molecule is very rigid and has four chiral centers. In addition to VCD and Raman measurements, Raman optical activity (ROA) measurements would be very enlightening, as in many cases bands which are weak in both the VA and VCD, may be large in the Raman and/or ROA spectra. The feasibility of using vibrational spectroscopy to monitor biological structure, function and activity is a worthy goal, but this work shows that a careful theoretical analysis is also required, if one is to fully utilize and understand the experimental results. The reliability, reproduceability and uniqueness of the vibrational spectroscopic experiments and the information which can be gained from them is discussed, as well as the details of the computation of VA, VCD and Raman (and ROA) spectroscopy for molecules of the complexity of aframodial, which have multiple chiral centers and flexible side chains. Festschrift in Honor of Philip J. Stephens’ 65th Birthday.     

Antioxidant Properties of Fruit and Vegetable Whey Beverages and Fruit and Vegetable Mousses

The study assesses the antioxidant activity, total phenolic content, total flavonoids content and lipophilic pigments (β-carotene, chlorophyll a, chlorophyll b) content in homemade and marketed fruit and vegetable whey beverages and fruit and vegetable mousses. All of the tests were performed using spectrophotometric methods. The highest polyphenol content was found in the homemade green whey beverage W1G (541.95 mg/100 g) and the lowest in the market green whey beverage W2G (46.18 mg/100 g). In the fruit and vegetable mousses under study, the highest content of polyphenolic compounds was determined in the red mousse R3 (76.41 mg/100 g). The highest content of flavonoids was observed in the homemade orange whey beverage W1O (63.06 mg/100 g) and in the green mousse G2 (69.80 mg/100 g). The values of the antioxidant activity of whey beverages and mousses varied depending on the composition. The highest content of β-carotene was identified in homemade orange whey beverage (4.36 mg/100 g) and in orange mousses (in range 1.10–2.24 mg/100 g), while chlorophylls a and b—in homemade green whey beverage W1G (3.00 mg/100 g and 1.31 mg/100 g respectively) and in green mousses (chlorophyll a in range 0.54 to 1.42 mg/100 g and chlorophyll b in range 0.13 to 0.32 mg/100 g).     

金、铜金属纳米棒或纳米线的AFM和SERS的研究(英文)

通过电化学氧化法制备具有不同孔径氧化铝模板 ,利用交流电镀的方法在模板中沉积金属 ,再用酸溶解模板可以得到相应尺度的金属纳米线或纳米棒的阵列 .本文利用原子力显微镜和表面增强拉曼技术分别表征了金和铜两种金属纳米线阵列 .研究结果表明 ,作为探针分子的硫氰(SCN )在金属纳米线上的碳氮三键的振动频率随纳米线直径的增大而蓝移 .这一现象可能是因为尺寸效应对纳米线的费米能级造成影响 ,使不同直径的金属纳米线电子结构存在微小的差别 .     

Anticancer and Antibiotic Rhenium Tri- and Dicarbonyl Complexes: Current Research and Future Perspectives

Organometallic compounds are increasingly recognized as promising anticancer and antibiotic drug candidates. Among the transition metal ions investigated for these purposes, rhenium occupies a special role. Its tri- and dicarbonyl complexes, in particular, attract continuous attention due to their relative ease of preparation, stability and unique photophysical and luminescent properties that allow the combination of diagnostic and therapeutic purposes, thereby permitting, e.g., molecules to be tracked within cells. In this review, we discuss the anticancer and antibiotic properties of rhenium tri- and dicarbonyl complexes described in the last seven years, mainly in terms of their structural variations and in vitro efficacy. Given the abundant literature available, the focus is initially directed on tricarbonyl complexes of rhenium. Dicarbonyl species of the metal ion, which are slowly gaining momentum, are discussed in the second part in terms of future perspective for the possible developments in the field.     

Formation and control of Turing patterns and phase fronts in photonics and chemistry

We review the main mechanisms for the formation of regular spatial structures (Turing patterns) and phase fronts in photonics and chemistry driven by either diffraction or diffusion. We first demonstrate that the so-called ‘off-resonance’ mechanism leading to regular patterns in photonics is a Turing instability. We then show that negative feedback techniques for the control of photonic patterns based on Fourier transforms can be extended and applied to chemical experiments. The dynamics of phase fronts leading to locked lines and spots are also presented to outline analogies and differences in the study of complex systems in these two scientific disciplines.     

Synthesis of Tyrosol and Hydroxytyrosol Glycofuranosides and Their Biochemical and Biological Activities in Cell-Free and Cellular Assays

Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.     

Homo- and copolymerizaton of norbornene and norbornene derivative with Ni- and Pd-based β-ketoiminato complexes and MAO

Neutral nickel(II) and palladium(II) complexes bearing β-ketoiminato ligand have been synthesized. The two complexes have been investigated as catalyst for the polymerization. Using methylaluminoxane (MAO) as a cocatalyst, both complexes produce vinyl-addition polynorbornenes, but palladium(II) complex displays much higher activity up to 8.0 × 10⁷ g/(molPd h). Furthermore, both Ni(II) and Pd(II)/MAO system can efficiently copolymerize norbornene and 5-norbornene-2-yl acetate (NB-OCOMe) in moderate yields and in relatively high molecular weights. The analyses of the product by FTIR, ¹H NMR and ¹³C NMR spectra give the verification of vinyl addition copolymer. The copolymers show narrow molecular weight distribution and good solubility in common organic solvents.     

Concentrations and distributions of trace and minor elements in Chinese and Canadian coals and ashes

A total of 35 trace and minor elements including some of environmental significance were determined in each of a selection of 15 Chinese and 6 Canadian thermal coals and their ashes by using the SLOWPOKE-2 nuclear reactor facility of the University of Toronto. The concentrations and distributions of these constituents among the coals and their combustion products (viz. ash and volatile matter) are presented together with an interpretation of their significance in relation to the large scale combustion of these coals as thermal fuels in industrialized countries such as China and Canada. The detailed results showed wide variations in trace impurity concentrations (up to a factor of 100 and more) among the coals studied with few large differences between those of Chinese and Canadian origin except that the rare earths, Sc, Th, U, I, and Se were much higher in the former, other halogens, As and Na were lower. Values for elemental enrichment factors (EF) relative to normal crustal abundances indicated that only As(EF=13), Br(5.7), I(16), S(230), Sb(11) and Se(320) were appreciably enriched in coal. During static ashing at 750°C most of the halogens, S and Se were volatilized whereas most other inorganic constituents were highly retained and concentrated in the ash by factors of 6 to 11.     

Comparative semiempirical and DFT study of styrylnaphthalenes and styrylquinolines and their photocyclization products

Semiempirical molecular orbital (PM3, PM6, and RM1) and density functional theory (DFT) (B3LYP/6‐31G*) studies are carried out for 1‐ and 2‐styrylnaphthalenes and their aza‐derivatives—2‐ and 4‐styrylquinolines. Relative stabilities of three isomeric forms: E‐ and Z‐isomers and the closed‐ring dihydrocyclophotoproduct (derivative of dihydrophenanthrene) are calculated. Compared to PM3, PM6 and especially RM1 understate heats of formation; in some cases, PM6 and RM1 even place Z‐isomer in energy below E‐isomer. PM3 rather close to DFT predicts heats of isomerization reaction, whereas PM6 and especially RM1 underestimate these values. Semiempirical methods in comparison with DFT markedly underestimate heats of cyclization reaction; however, reproduce trends in relative stabilities of different isomers in dependence on the structure of styrylnaphthalenes and styrylquinolines. Qualitative correlation is found between calculated relative stabilities of the closed‐ring forms (heats of cyclization reaction) and experimental data: cyclized products with low heats of cyclization are observed in steady‐state photolysis and those with high heats of cyclization are not. In the latter case, the closed‐ring compounds, if formed in the excited state, due to thermal instability decompose rapidly with ring opening in the ground state that prevents their observation. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

钒与糖代谢及糖尿病

微量元素钒作为生物体内必需元素，经证实有很重要的生理学功能，与机体糖代谢有十分密切的关系，且能降低糖尿病动物模型的高血糖，极有可能被开发为治疗糖尿病的药物。     

Preparation and photochromic properties of dye-doped aluminosilicate and ORMOCER gels and coatings

Aluminosilicate and ORMOCER gels and coatings containing photochromic dyes, 1, 3-dihydro-1, 3, 3-trimethylspiro-[2H-indole-2, 3-[3H]-naphth-[2, 1-b][1, 4]-oxazine] (SO) and 1, 8a-dihydro-2, 3-dimethoxycarbonyl-spiro [fluorene-9, 1-indolizine] (DHI), were prepared by the sol-gel method and the photochromic activity was monitored in the course of the sol-wetgel-xerogel transformation. The photochromic activity of the aluminosilicate gels decreases rapidly and even vanishes in the wetgel-xerogel stage while that of ORMOCER gels and coatings levels off in the early wetgel-xerogel stage at a reasonably high photochromic intensity with the colour-fading speed similar to that in ethanol and the photostability being considerably improved. The experimental results are discussed in terms of the matrix effect on photochromism of organic dyes.     

Syntheses of 7-fluoro- and 6,7-difluoroserotonin and 7-fluoro- and 6,7-difluoromelatonin

The Abramovitch adaption of the Fischer indole synthesis gave low yields of 7-fluoro-5-methoxytryptamine due in part to decomposition during the required decarboxylation step. Therefore, 7-fluoro- and 6,7-difluoro-5-methoxytryptamines were prepared by reaction of aminobutyraldehyde (generated in situ from the diethyl acetal) with 2-fluoro- and 2,3-difluoro-4-methoxyphenylhydrazine, and the products converted to the corresponding serotonins. The melatonins were prepared by a one-pot reaction that involved in situ acetylation of the aminobutyraldehyde.     

软硬酸碱规则与体内微量元素

阐述了ＳＨＡＢ规则,分类,酸碱软硬度的定量标度和理论解释。根据ＳＨＡＢ规则把体内微量元素分为Ｌｅｗｉｓ硬酸,软酸与交界酸和硬碱,软碱与交界碱,体内不同体液和器官含有丰富的软硬配体,与各类软硬酸（金属离子）结合成不同稳定性的配合物,发挥其生物活性作用。     

Chemoenzymatic Synthesis of Cylindrocyclophanes A and F and Merocyclophanes A and D

Incorporating enzymatic reactions into natural product synthesis can significantly improve synthetic efficiency and selectivity. In contrast to the increasing applications of biocatalytic functional-group interconversions, the use of enzymatic C−C bond formation reactions in natural product synthesis is underexplored. Herein, we report a concise and efficient approach for the synthesis of [7.7]paracyclophane natural products, a family of polyketides with diverse biological activities. By using enzymatic Friedel–Crafts alkylation, cylindrocyclophanes A and F and merocyclophanes A and D were synthesized in six to eight steps in the longest linear sequence. This study demonstrates the power of combining enzymatic reactions with contemporary synthetic methodologies and provides opportunities for the structure–activity relationship studies of [7.7]paracyclophane natural products.     

Adsorption and Mobility of Water and Benzene Molecules in Carbon and Polymer Adsorbents

The correlation between the adsorption and the mobility of adsorbed molecules was analyzed. The peculiarities of molecular mobility in microporous adsorbents with relatively rigid (active carbons) and non-rigid (polymer super-crosslinked and methacrylate sorbents) structure were studied using pulsed nuclear magnetic resonance (NMR) techniques. It was shown that the translational behavior of water and benzene in pores are connected with the specific adsorption mechanism. The NMR data allowed analyzing the changes of molecular state in the processes of adsorption. Diffusional properties of water molecules in the super-crosslinked polystyrenes and active carbons with relatively rigid framework are similar and differ from that in methacrylate polymer sorbents. Moreover, the results of NM relaxation measurements allowed analyzing the porous structure over the scale of pore sizes, while the scale of the self-diffusion measurements comprises the areas of different porosity. The NMR data agree well with the data of adsorption measurements and complement them. Dedication: This work is devoted to memory of the professor W. Schirmer.     

药物免疫分析及其进展

本文对用于检测药物的免疫技术作了概述，并总结了近年来一些分析体系的改进和发展，同时指出了现代药物免疫分析的一些新的发展趋势，其中包括多分析物免疫分析方法，新型均相免疫分析方法，以及色谱、流动注射技术等在药物免疫分析中的应用。免疫分析技术可使今后药物定量检测更为灵敏，快速。