Extraction Process Optimization and Moisturizing Performance of Fucoidan from Sargassum fusiforme

[Objectives] The research aimed to optimize extraction process of fucoidan from Sargassum fusiforme( FSF) and study its moisturizing performance. [Methods]Extracting condition of FSF by cellulase hydrolysis-ultrasonic assisted extraction method was optimized. The influences of solvent p H,enzyme dosage,extraction temperature,cellulose hydrolysis time,ultrasonication time,and the ratio of material to liquid on FSF were investigated by single factor and orthogonal experiments. [Results] The optimum extraction conditions were as followings:p H,4. 5; enzyme dosage,1%; extraction temperature,40℃; cellulose hydrolysis time,2 h; ultrasonic time,15 min; and the ratio of material to liquid,1∶ 10( g∶ m L). Under the optimal condition,the extraction yield of FSF was 8. 50%,RSD = 2. 74%. The short-time hygroscopicity( within 8 h) of crude extract of fucoidan from S. fusiforme( CEFSF) was better than glycerin,butanediol,and sodium alginate,and the moisture retention capacity of 1% CEFSF aqueous solution was better than 1% butanediol or 1% sodium alginate,and was equal to 5% glycerin under relative humidity of 43% and 81%. The determination results of skin moisture content and transepidermal water loss rate( TEWL)showed that: 5% CEFSF solution had good moisturizing effect. [Conclusions]The research could provide certain reference for deep development of S. fusiforme.

Completely Green Synthesis of Ag Nanoparticles Stabilized by Soy Protein Isolate under UV Irradiation

A completely green pathway for the preparation of Ag nanoparticles was proposed, by using soy protein isolate （SPI） as stabilizer under UV irradiation and H2O as the environmentally benign solvent throughout the preparation. Transmission electronic microscopy （TEM） and zeta potential characterization results indicated that the Ag nanoparticles were stable and well dispersed with an average diameter about 13 nm, and X-ray diffraction （XRD） analysis of SPI/Ag composite nanoparticles confirmed the formation of metallic silver. UV-Vis spectrum showed that the Ag nanoparticles dispersion solution had the maximum absorbance at about 430 nm due to surface plasmon resonance of the Ag nanoparticles. Infrared spectroscopy confirmed that the polypeptide backbone of SPI was not cleaved during the conjugation process and that some active amino groups were oxidized. The SPI/Ag composite nanoparticles have excellent antibacterial activity against two representative bacteria, staphylococcus aureus （Gram positive） and escherichia coli （Gram negative） in the presence of SPI.

表面活性剂双水相分离茶多酚生产废液中的茶氨酸(英文)

Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactant two-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that the region of ASTP is narrow and there is only a two-phase region of cationic surfactant. The increase in concentrations of NaBr and Na2SO4 are beneficial to the formation of ASTP. Theanine concentration in the bottom phase increases with increasing concentration of theanine, whereas the partition coefficient and extraction rate only change a little when the concentration of theanine is above 0.2 g·L-1 . With the increase of SDS concentration, the phase ratio and the partition coefficient decrease, while the extraction efficiency of theanine increases and the concentration of theanine changes a little in the range from 2.4/7.5 to 2.8/7.2 for SDS/CTAB ratio. The temperature has a notable effect on the concentration of theanine in the bottom phase, partition coefficient and extraction rate of theanine. The increase of waste liquid decreases the phase ratio, increases the concentration and extraction rate of theanine in the bottom phase, since the protein and the saccharide enter the bottom phase with theanine.

Fabrication of 3D biomimetic composite coating with broadband antireflection, superhydrophilicity, and double p-n heterojunctions

The traditional single material with two-dimensional （2D） biomimetic moth-eye structures is limited by its narrowband antireflection and single functional capability. To overcome these disadvantages, we exploited wet etching and hydrothermal synthesis coupled with chemical oxidation for fabricating a three- dimensional （3D） biomimetic moth-eye coating with ternary materials （polypyrrole nanoparticles, TiO2 nanorods, and Si micropyramids, i.e., PPy/TiOa/Si-p）. This coating reduced the reflectivity to 〈4% at wavelengths ranging from 200 to 2,300 nm and exhibited remarkable superhydrophilidty with a low water contact angle of 1.8°. Moreover, the composite coating had double p-n heterojunctions, allowing the high-efficiency separation of photogenerated carriers. The photo- current density of PPy/TiO2/Si-p was more than three times higher than that of TiO2/Si-p at a positive potential of 1.5 V. The proposed method provides a means to enhance solar energy conversion.

Effect of Different Ionic Liquids on 5-Hydroxymethylfurfural Preparation from Glucose in DMA over AlCl_(3):Experimental and Theoretical Study

In this work,effect of different ionic liquids(ILs)on 5-hydroxymethylfurfural(HMF)preparation from glucose in N,N-dimethylacetamide(DMA)over AlCl3 was revealed by a combined experimental and computational study.ILs used as cocatalysts in this work included N-methyl-2-pyrrolidone hydrogen sulfate([NMP]HSO_(4)),N-methyl-2-pyrrolidone methyl sulfate([NMP]CH_(3)SO_(3)),N-methyl-2-pyrrolidone chlorine([NMP]Cl)and N-methyl-2-pyrrolidone bromide([NMP]Br)which were endowed with the same cation but different anions.According to the conclusion that fructose was intermediate product from glucose to HMF,we found fructose was transformed to more by-products by[NMP]H_(S)O_(4),making HMF yield decline significantly when glucose was treated as substrate.Neither glucose nor fructose could be converted by[NMP]CH_(3)SO_(3)efficiently,leading to its no influence on glucose conversion to HMF.[NMP]Br had a higher selectivity for HMF from fructose than[NMP]Cl and AlCl3.Besides,Al^(3+)preferred to combine with Br−,slightly decreasing both the overall free energy barrier for glucose isomerization and activation barrier for H-shift at 393.15 K.So a high HMF yield of 57%was obtained from glucose catalyzed by AlCl3 together with[NMP]Br under mild conditions.

Synthesis and Properties of Degradable Copolymers Com- posed of Poly（E-caprolactone） and 3,4-Dihydroxycinnamic Acid

Photoreactive and degradable hyperbranched （HB） copolymers with various 3,4-dihydroxycinnamic acid （DHCA） compositions, poly（e-caprolactone）-co-poly（3,4-dihydroxycinnamic acid） （PCL-co-PDHCA）, were ob- tained by thermal melt-polycondensation of PCL and DHCA. The HB structures and the branching degree （BD） of the PCL-co-PDHCA copolymers were confirmed by Fourier transform infrared spectroscopy （FTIR） and nuclear magnetic resonance （1H NMR）. The melting points （Tm） of the PCL-co-PDHCA copolymers changed depending on the PCL and DHCA composition by differential scanning calorimetry （DSC） measurements. Wide angle X-ray dif- fraction （WXRD） analysis showed semi-crystalline of the PCL and PCL-co-PDHCA polymers. The PCL-co-PDHCA copolymers showed good photoreactivities and fluorescent properties. Crosslinking of the cin- namoyl groups in the copolymers caused by UV irradiation affected the thermal stability and wettability slightly. Moreover, the hydrolysis experiments revealed that copolyrners are facile degradable.

Facile and Controllable Assembly of Multiwalled Carbon Nanotubes on Polystyrene Microspheres

Herein a facile and controllable heterocoagulation between polystyrene （PS） microspheres and multiwalled carbon nanotubes （MWCNTs） is introduced based on colloid thermodynamics. The MWCNTs play the role of steric stabilizer for stabilizing the metastable PS microspheres and thus immobilize spontaneously on the surface of PS microspheres. The synthesized MWCNTs-coated PS composite particles have been extensively characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetry and Raman spectroscopy. The results indicate that the structure and morphology of the resultant MWCNTs-coated PS composite particles are significantly affected by the weight ratio of PS and MWNCTs and the amount of poly（vinylpyrrolidone） that is injected into PS dispersion before they are mixed with MWCNTs. Therefore, these composite particles have the potential to produce MWCNTs-based composite materials with controllable mass loading and dispersity of MWCNTs.

Gold-Loaded Polymeric Micelles with TemperatureModulated Catalytic Activity

Four-armed amphiphilic block copolymers, polystyrene-b-poly(N-isopropylacrylamide)(PS-bPNIPAM)4, were synthesized by atom transfer radical polymerization(ATRP).(PS-b-PNIPAM)4 self-assembled into micelles with PS block as core and thermoresponsive PNIPAM block as corona. The gold nanoparticles(Au NPs) with average diameter about 5.8 nm were immobilized on the surfaces of the micelles by the reduction of the corresponding ions. The micelle-supported gold nanoparticles(Au-micelles) were applied to catalyze the reduction of p-nitrophenol. Moreover, the activity of the Au-micelle catalyst could be modulated by the temperature and the Au-micelles could be easily recovered by changing the temperature and recycled four times with high catalytic activity.

Well-dispersive K2O-KCl alkaline catalyst derived from waste banana peel for biodiesel synthesis

In this work, a novel alkaline catalyst was synthesized by an economical and effective method of roasting waste banana peel. From XRD, FTIR, SEM, EDS, TGA and CO2-TPD characterization, it was proved that the calcined banana peel catalyst showed the strong alkalinity and well dispersity in microstructure, and K2O-KCl as the main active contents. The calcined banana peel catalyst showed better catalytic performance than the catalysts by physical mixing of K2O and KCl, which was due to good dispersibility of K2O-KCl formed during decomposing of carbon fiber by calcination of banana peel. Furthermore, the calcined banana peel catalyst also performed well in both water-resistant ability and recyclability, indicating their potential for biodiesel production from an efficient, robust, and low-cost catalyst.

Asymmetric Hydrosilylation of Aromatic Ketones Catalyzed by an Economical and Effective Copper-Diphosphine Catalytic System in Air

In the presence of the inexpensive and non-toxic polymethylhydrosiloxane, the combination of copper(II) acetateand a chiral diphosphine displayed high catalytic efficiency in the asymmetric hydrosilylation of a series ofaromatic ketones in air atmosphere and at room temperature. (R)-1-Arylethanols were obtained with up to 99%yield and 93% enantiomeric excess. Meanwhile, the electron effect and steric hindrance of substituents on the aromaticring had an interesting influence on both the yields and enantioselectivities. Furthermore, a possible mechanismwas presented to explain the influence of some key factors on the reaction.

Facile and Convenient Fabrication of Color-controlled Colloidal Magnetically Assembled Photonic Crystals

A facile, convenient and flexible method to tune the structural color of the colloidal magnetically assembled photonic crystals（CMA-PCs） was proposed. The mechanism to tune structural color could be attributed to the significant influence of the surfactant sodium dodecyl sulfate（SDS） concentration on the particle size, especially on the magnetite content of the superparamagnetic composite nanoparticles（MCNPs）. By adjusting SDS concentra- tion in miniemulsion polymerization of MCNPs, CMA-PCs with desired diffraction colors could be obtained.

One-step synthesis of fluorescent smart thermo- responsive copper clusters： A potential nanothermometer in living cells

与在生活房间探查的敏感温度一起，在生物学和医药诊断的温度测量是很重要的；然而，它仍然面对重要挑战。有吸引人的光性质的金属 nanoclusters (NC ) 可能正在答应候选人克服如此的挑战。这里，一出新奇一步舞合成方法被介绍准备高度荧光灯处于由把谷胱甘肽(GSH ) 用作减少的代理人和阻止同样形成的 NC 的聚集的保护的层的周围的条件的铜 NC (CuNCs ) 。结果的 CuNCs 与 2.3 nm 的一条平均直径，包含 13 原子和展览红荧光( 他们 = 610 nm ) 与高量收益(QY，多达 5.0%) 。有趣地， CuNCs 的荧光信号在意大利对在 1580 的范围的环境温度 reversibly 应答。学习题目经历了 ba 慀 ? 慀吗？？

Synthesis of Visible-Light-Driven g-C3N4/PPy/Ag Ternary Photocatalyst with Improved Photocatalytic Performance

g-C3N4/PPy/Ag ternary photocatalyst was synthesized by a three-step method. Firstly, graphitic carbon nitride （g-C3N4） photocatalyst was obtained by sintering melamine at high temperature, then a series ofg-C3N4/PPy com- posite photocatalysts were prepared by in-situ polymerization of pyrrole, and finally the g-C3N4/PPy/Ag ternary composite photocatalyst was obtained by depositing Ag on the surface of g-C3N4/PPy. The photocatalytic activities of as-prepared samples were evaluated by degradation of antibiotic tetracycline （TC） under visible light. The influ- ence of the amounts of polypyrrole （PPy） and Ag on the photocatalytic activity of g-C3N4/PPy/Ag ternary photo- catalyst was investigated. Both PPy and Ag played critical roles for the enhanced photocatalytic activity of g-C3N4/PPy/Ag. The g-C3N4/PPy/Ag composites exhibited remarkably improved photocatalytic activities for de- grading TC compared with g-C3N4, g-C3N4/PPy and g-C3N4/Ag. Besides, the photocatalytic mechanism was also analyzed. The band match of PPy with g-C3N4 benefited the separation of photo-generated carriers in g-C3N4, and the deposited Ag nanoparticles played important roles as an electron mediator due to the surface plasmon resonance （SPR） effects. The present study offered new insight into the design of the economical and gently environ- ment-friendly synthesis of highly efficient photocatalysts.

Effect of various functional groups on biodiesel synthesis from soybean oils by acidic ionic liquids

Preparation of biodiesel from soybean oils catalyzed by five acidic ionic liquids with three cationic functional groups was investigated. The improvement of the catalytic activities was affected by various functional groups including pyridine group, N- methylimidazole group, triethylamine group. Among them [C4SO3Hpy]HSO4 with pyridine group showed better catalytic activity with the biodiesel yield of 94.5%, and still yielded more than 90% after six successive uses. The possible mechanism was also discussed by two reaction paths in detail.