光活性体N-马来酰基-L-丙氨酸/苯乙烯的合成

以过硫酸钾为引发剂,在微乳液中合成了具有旋光性的N-马来酰基-L-丙氨酸(AMI)与苯乙烯(St)的共聚物。用元素分析法测定了共聚物内氮摩尔分数,从而确定了共聚物摩尔组成与单体配比之间的关系.进而计算出AMI与St的竞聚率分别是0.05,0.10,并计算出相应的AMI单体活性值为1.59、AMI单体极性值为1.50.讨论了共聚物旋光性的成因以及旋光性共聚物的结构。结果表明,该共聚物具有交替共聚合的倾向。

光活性预聚体——聚醚聚氨酯丙烯酸酯的合成与表征

以２．４－ＴＤＩ、不同分子量聚醚及丙烯酸羟丙酯为原料合成了一系列具有光活性的预聚体；利用红外光谱、化学分析、粘度、硬度、拉伸强度等测试手段对树脂的性能进行了表征；研究和探讨了不同分子量的聚醚、ＮＣＯ／ＯＨ的摩尔比，不同的投料方式及反应温度等因素对树脂的结构和性能的影响．

载光敏剂磁性纳米粉的制备及其光敏活性

采用乳化和共沉淀法,制备了载四(对-羟基苯基)卟啉光敏剂的磁性纳米粉。通过X射线衍射、透射电子显微镜、红外光谱、振动探针式磁强计(VSM)、紫外可见光谱等测试技术对磁性纳米微粒的大小、形貌、化学成分、磁化率及其光敏剂含量等进行了测试表征;利用MTT法测定了该磁性纳米光敏剂对人结肠癌Lovo细胞株的体外光动力活性。结果表明,该磁性纳米微粒呈较规则的球形,粒径<50 nm。其Fe3O4磁核被葡聚糖包裹,质量磁化率为68.27 emu/g,光敏剂含量为8.5%。当Lovo细胞培养液中,加入含光敏剂最终浓度为1×10-6mol/L的磁性纳米粉并光照30 min后,对该细胞的体外抑制率达到81.85%。

国内紫外光固化涂料的发展及应用

紫外光固化涂料是一种节能和环境友好型涂料,本文首先介绍了紫外光固化涂料的特点、固化机理、组成紫外光固化涂料的各种组分及其作用,然后对紫外光固化涂料的发展现状与应用领域进行了详述,最后指出,未来紫外光固化涂料的研究和发展应朝水性化和粉末化方向发展。

Surface plasmon resonance-induced visible-light photocatalytic performance of silver/silver molybdate composites

Novel silver/silver molybdate（Ag/Ag2MoO4） composites with surface plasmon resonance（SPR）-enhanced photocatalytic performance were successfully fabricated via a facile one-pot hydrothermal route with the presence of sodium dodecyl sulfate（SDS） in this study.The as prepared silver/silver molybdate（Ag/Ag2MoO4） composites were systematically characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM） and ultraviolet-visible diffuse reflectance absorption spectroscopy（DRS） in order to investigate their crystal structure,morphology and optical property as well.The photocatalytic activities of the composites were subsequently evaluated by their ability to degrade rhodamine B（RhB） under visible-light irradiation.Varies of controlled experiments were then carefully operated to gain a deep insight into the assembling of Ag/Ag2MoO4composites.It was found that preparation conditions such as pH,reaction time,and the amount of surfactant played important roles in the formation of composites with octahedral microstructures.And the composite obtained at 160 ℃ using 0.5 g of sodium dodecyl sulfate exhibited the highest photocatalytic performance under visible-light irradiation.Capture experiments were also conducted to clarify the function of different active species generated on the surface of Ag/Ag2MoO4during the photocatalytic process,in which both holes and ·OH radicals were found to play crucial role in photocatalytic removal of RhB under visible light irradiation.A possible photocatalytic mechanism of Ag/Ag2MoO4 was finally proposed on the basis of all the results to explain the higher photocatalytic activity of the octahedral Ag/Ag2MoO4 composites.It was inferred that the photoinduced ＂hot＂ electrons can quickly transfer from the Ag NPs to the conduction band of Ag2MoO4 and react with oxygen and H2O to generate a large quality of active radicals such as ·OH and ·O2^- because of the SPR effects.Besides,this SPR effects of Ag nanoparticles deposited on the surface of Ag2MoO4 can not only dramatically amplify its light absorption,especially in the visible region,but also promote the separation of photoexcited electron-hole pairs and effectively decrease electron-hole recombination.

Hydrothermal synthesis of monodisperse Zn_(x)Cd_(1-x)S spheres and their photocatalytic properties

Monodisperse ZnxCd1-xS spheres were successfully fabricated with a high yield by a facile hydrothermal route.The as-prepared samples were characterized by X-ray diffractometry,scanning electron microscopy and UV-vis diffusion reflectance spectroscopy.The results indicate that all the prepared samples have the same hexagonal wurtzite phase and exhibit good size uniformity and regularity.Degradation of rhodamine-B（RhB） was used to evaluate the photocatalytic activities of ZnxCd1-xS samples.Zn0.4Cd0.6S possessed the best photocatalytic activity and exhibited high stability during the reaction.

Effect of carrier and axial ligand on the photocatalytic activity of cobalt thioporphyrazine

The photocatalytic activity of cobalt octakis（butylthio） porphyrazine（CoPz（BuS）8） was assessed through photodegradation of the dye rhodamine B（RhB） in water under irradiation with a Xe lamp and aerated conditions.The photocatalytic activity of CoPz（BuS）8 loaded on Al2O3 or SiO2@Fe3O4nanoparticles or coordinated with an axial azide ligand was also investigated.The results demonstrated that the photocatalytic activity of CoPz（BuS）8 loaded on Al2O3 was higher than that loaded on SiO2@Fe3O4.The kinetic curves of RhB degradation in aqueous solutions at different pH indicated the pseudo first-order kinetics of the reaction.The highest degradation rate for CoPz（BuS）8 loaded Al2O3 at pH = 4 after 160 min was 84.6%.However,the advantages of easier separation and recycling as well as the ability to terminate the reaction at any time for the CoPz（BuS）8 loaded SiO2@Fe3O4 cannot be ignored.When electron-rich NaN3 was coordinated with CoPz（BuS）8 as an axial ligand and loaded on Al2O3,the resulting catalyst produced more active oxygen species such as O2^- and HO· to promote the quicker degradation of RhB than that by the other catalysts.For the N3-coordinated CoPz（BuS）8 loaded on Al2O3,the reactions at pH = 4 and 7 distinctly deviated from first-order kinetics,and the degradation rate reached 77.6%after 80 min at pH = 4.

Effect of high-voltage discharge non-thermal plasma on g-C_3N_4 in a plasma-photocatalyst system

The synergistic effect of high voltage discharge non‐thermal plasma(NTP)and photocatalysts on contaminant removal has repeatedly confirmed by plenty of researches.Most previous plasma‐photocatalyst synergistic systems focused on the utilization of the ultraviolet light but ignored the visible light generated by high voltage discharge.Graphitic carbon nitride(g‐C3N4),a metal‐free semiconductor that exhibits high chemical stability,can utilize both the ultraviolet and visible light from high voltage discharge.However,the synergistic system of NTP and g‐C3N4 has been researched little.In this paper,the effect of NTP generated by dielectric barrier discharge(DBD)on g‐C3N4 is studied by comparing the photocatalytic activities,the surface physical structure and the surface chemical characteristics of pristine and plasma treated g‐C3N4.Experimental results indicate that the DBD plasma can change the physical structure and the chemical characteristics and to further affect the photocatalytic activity of g‐C3N4.The effect of NTP on g‐C3N4 is associated with the discharge intensity and the discharge time.For a long time scale,the effect of NTP on g‐C3N4 photocatalysts presents a periodic change trend.

Pyropia yezoensis can utilize CO_2 in the air during moderate dehydration

Pyropia yezoensis, an intertidal seaweed, experiences regular dehydration and rehydration with the tides. In this study, the responses of P. yezoensis to dehydration and rehydration under high and low CO2 concentrations （（600-700）×10^-6 and （40-80）×10^-6, named Group I and Group II respectively） were investigated. The thalli of Group I had a significantly higher effective photosystem II quantum yield than the thalli of Group II at 71% absolute water content （AWC）. There was little difference between thalli morphology, total Rubisco activity and total protein content at 100% and 71% AWC, which might be the basis for the normal performance of photosynthesis during moderate dehydration. A higher effective photosystem I quantum yield was observed in the thalli subjected to a low CO2 concentration during moderate dehydration, which might be caused by the enhancement of cyclic electron flow. These results suggested that P. yezoensis can directly utilize COz in ambient air during moderate dehydration.

杀虫剂硫丹的制备工艺

美国专利US20040092751公开了制备杀虫剂硫丹的新工艺；该专利称制得的硫丹不仅光活性有效体纯度高，而且非有效体可以回收并循环使用进而制得有效体。(LCL)

Preparation, Spectral Identification and Analytical Studies of Some Transition Metal Complexes with New Thiazolylazo Ligand and Their Biological Activity Study

A new MeTAMP （thiazolylazo dye ligand 2-[2-（5-methyl thiazolyl）azo]-4-methoxy phenol） was prepared by coupling reaction between 5-methyl thiazolylazonium chloride with 4-methoxy phenol in alkaline alcoholic solution. The structure of azo dye ligand has been characterized by available technique such as 1H-NMR, mass spectrum, FT-IR, UV-vis and elemental analysis. Eight new chelate complexes of Cr（III）, Mn（II）, Fe（II）, Fe（III）, Co（III）, Ni（II）, Cu（II） and Zn（II） ions were prepared and identified by elemental analysis, atomic absorption, magnetic susceptibility, molar conductance measurements, FT-IR and electronic spectra. The spectral and analytical data show that the ligand a tridentate and coordinating with metal ions through the phenolate O, azo N atom which is the farthest of thiazole molecule and with thiazole N atom. The molar ratio （M：L） was also studied which was found 1：1 for Zn（II） and 1：2 for the rest metal ions. Conductivity measurements for prepared complexes showed 1：1 electrolyte for Cr（III）, Fe（IlI）, and Co（llI） complexes and non-electrolyte for rest complexes. Stability constants of complexes were calculated by spectrophotometry. Octahedral configuration suggested for Cr（III）, Mn（II）, Fe（II）, Fe（III）, Co（III）, Ni（II） and Cu（II） but tetrahedral for Zn（IlI） complex. The solid complexes are found to have the general formula IML2]Cl H2O where M = Cr（III）, Fe（III） and Co（IIl） and [ML2] H2O where M = Mn（II）, Fe（II）, Ni（II） and Cu（II） while [MLCI].H20 for Zn（II）-complex. The biological activity of ligand and its complexes against five types of bacteria, Strepto coccus and Staphylococcus aureus as example of gram positive, Pseudomonas, Proteus and Esherichia coli as example of gram negative bacteria by agar plate different technique was studied. The activity was also assayed on molecular level by using PCR in an attempt to monitor DNA banding pattern.

紫外光固化涂料的研究现状

紫外光固化涂料是一种新型的绿色涂料 ,近几年发展迅速。文中从紫外光固化技术的原理出发 ,概述了国内外研究进展。介绍了光固化涂料的各个组成部分及其发展情况 ,分析其性能和结构的关系 ,提出了既要开展理论研究又要重视应用研究的新思路。在展望了紫外光固化涂料发展前景的同时 。

Observation of mitochondrial activity based on temporal and spatial pH variations measured by near-field fluorescent ratiometry

A novel method combining dual wavelength fluorescent ratiometry with scanning near-field optical microscopy (SNOM) is proposed and developed to measure the concentration and distribution of protons in the vicinity of biological samples. This method involves immersing mitochondria in a pH-sensitive fluorescent dye solution instead of injecting the dye into the surface of the mitochondrial membrane. It uses a dual emission pH-sensitive dye and SNOM with a thermally pulled and metal-coated optical fiber probe to improve the spatial resolution. The time dependence of the fluorescence intensity ratio (FIR) under acid addition and the response of mitochondria to nutritional supplementation were studied by using this method. Activation of mitochondria and a distance-dependent delay in the FIR response were observed. The results confirmed that mitochondrial activity could be observed by using this method.

Enhanced photoresponsivity and hole mobility of MoTe_2 phototransistors by using an Al_2O_3 high-κ gate dielectric

Molybdenum ditelluride （MoTe2） has been demonstrated great potential in electronic and optoelectronic applications. However, the reported effective hole mobility remains far below its theoretical value. Herein, taking advantage of high-κ screening effect, we have fabricated back-gated MoTe2 transistors on an Al2O3 high-κ dielectric and systematically investigated the electronic and optoelectronic proper- ties. A high current on/off ratio exceeding 106 is achieved in the Al2O3-based MoTe2 transistors, and the hole mobility is demonstrated to be 150 cm2 V^-1 s^-1, compared to 0.2-20 cm^2 V^-1 s^-1 ever obtained from back-gated MoTe2 transistors in the literatures. Moreover, a considerable hole concentration of 1.2 × 10^13 cm 2 is attained in our Al2O3-based MoTe2 transistors owing to the strong gate control capa- bility, leading to a high on-state hole current of 6.1 μA μm^-1. After optimization, our Al2O3-based MoTe2 phototransistor exhibits outstanding photodetective performance, with a high responsivity of 543 AW^-1 and a high photogain of 1,662 at 405 nm light illumination, which are boosted around 419 times compared to the referential SiO2-based control devices. The mechanisms of photoconductivity in the Al2O3-based MoTe2 phototransistors have been analyzed in detail, and the photogating effect is considered to play an important role. This work may provide useful insight to improve carrier mobility in two-dimensional layered semiconductors and open opportunities to facilitate the development of high-performance photodetectors in the future.

Ab initio simulation of the sum-frequency generation response of optically active liquids in the presence of a dc electric field —determination of the absolute molecular configuration

Quantum chemical computations have been performed to evaluate the first and second hyperpolarizability quantities of the interference term, linear in the external static electric field, that appear in the electric field-induced sum-frequency generation signal of chiral liquids. These are performed at the time-dependent Hartree-Fock level on the prototypical 1,1′-bi-2-naphtol chiral species.

Biocatalytic desymmetrization of 3-substituted glutaronitriles by nitrilases. A convenient chemoenzymatic access to optically active (S)-Pregabalin and (R)-Baclofen

Desymmetrization of prochiral 3-substituted glutaronitriles offers a new approach to access （S）-Pregabalin and （R）-Baclofen. A number of nitrilases from diverse sources were screened with 3-isobutylglutaronitriles （1a） or 3-（4＇-chlorophenyl）glutaronitriles （1b） as the substrate. Some nitrilases were found to catalyze the desymmetric hydrolysis of la and lb to form optically active 3-（cyanomethyl）-5-methylhexanoic acid （2a） and 3-（4＇-chlorophenyl）-4-cyanobutanoic acid （2b） with high enantiomeric excesse （ee）, respectively. This cannot be achieved using traditional chemical hydrolysis. Among them, AtNIT3 generated （R）-2b whereas BjNIT6402 and HsN1T produced the opposite （S）-enantiomer with high conversions and ee values. Not only the nitrilases showed different activities and stereoselectivities toward these 3-substituted glutaronitriles, the 3-substitueut of the substrates also exerted great effect on the enzyme activity and stereoselectivity. （S）-2a and （S）-2b were prepared with high yields and ee values using BjNIT6402 and HsNIT as the biocatalysts, respectively. A straightforward Curtius rearrangement of （S）-2a and （S）-2b, followed by the acidic hydrolysis, afforded （S）-Pregabalin and （R）-Baclofen. This offers a new platform methodology for the synthesis of optically active β-substituted T-amino acids of pharmaceutical importance.

ZnO nanopowders and their excellent solar light/UV photocatalytic activity on degradation of dye in wastewater

Low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O nanopowders(NPs)would determine their practical application in purifying wastewater.In this contribution,ZnO NPs were scalably synthesized via the simple reaction of Zn powder with H_2O vapor in autoclave.The structural,morphological and optical properties of the samples were systematically characterized by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectra,transmission electron microscopy,Micro-Raman,photoluminescence,and ultraviolet-visible spectroscopy.The as-prepared Zn O NPs are composed of nanoparticles with 100–150 nm in diameter,and have a small Brunauer-Emmett-Teller surface area of 6.85 m^2/g.The formation of Zn O nanoparticles is relative to the peeling of H_2 release.Furthermore,the product has big strain-stress leading to the red-shift in the band gap of product,and shows a strong green emission centered at 515 nm revealing enough atomic defects in Zn O NPs.As a comparison with P25,the obtained dust gray Zn O NPs have a strong absorbance in the region of 200–700 nm,suggesting the wide wave-band utilization in sunlight.Based on the traits above,the Zn O NPs show excellent photocatalytic activity on the degradation of rhodamine B(Rh-B)under solar light irradiation,close to that under UV irradiation.Importantly,the Zn O NPs could be well recycled in water due to the quick sedimentation in themselves in solution.The low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O NPs endow themselves with promising application in purifying wastewater.