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The water-stable PAA/PVA/PW 12 nanofiber was firstly prepared by electrospinning and thermal treatments. The negatively charged phosphotungstic acid (PW 12 ), positively charged polyethylenimine (PEI) and silver nanoparticle (Ag NPs) were alternatively deposited onto the fibrous substrate by layer-by-layer (LBL) self-assembly technique. The photocatalytic activity of different coated LBL film was observed under visible light irradiation. The results indicated that the conversion rate of methylene blue (MB) was gradually decreased with increasing the number of bilayers pairs. The behavior might ascribe to the more polycation electrolyte PEI that prevented from permeating for the MB molecule. On the other hand, in terms of the effects of surface charges on the photocatalytic activity, negatively charged surface (PEI) n (PW 12 ) n indicated higher photocatalytic activity than that of positively charged surface (PEI) n (PW 12 ) n − 1 . For the Ag NPs deposited on the LBL film, Ag-(PEI) n (PW 12 ) n film were found to be a better photocatalytic activity than other multilayer films, specially, Ag-(PEI) 2 (PW 12 ) 2 exhibited the most excellent activity due to the influence of the synergy in the hybrid materials.

Stimuli-responsive luminescent hybrid nanoparticles consisting of a magnetite Fe3O4 core and a hydrophilic outer shell were synthesized. The shell was a thermo-responsive Eu(III) complex shell, which was synthesized as follows: first, 3-Methacryloxypropyl-trimethoxysilane (MEMO)-co-poly(N-isopropylacrylamide) (NIPAM) (MEMO-co-PNIPAM) copolymer was prepared by free radical polymerization. Subsequently, the copolymer chelated with Europium(III) ions to form a luminescent polymeric layer. Finally, the polymeric shell was grafted onto the Fe3O4 nanoparticles surface through chemical action. The sizes of fabricated nanoparticles with core���shell structure were controlled at about 30-45 nm. The as-synthesized nanocomposite particles had excellent fluorescence performance and thermo-responsive behavior, which possessed high color purity and produced red-emission at 613 nm. The lower critical solution temperature (LCST) of thermo-sensitive magnetic nanoparticles was at around 37���38 ��C. Cell viability assays suggested that these nanoparticles showed excellent biocompatibility and fluorescence-intensity in vitro.

Three dimeric mono-Fe(III)-substituted polyoxotungstates [C16H33(CH3)3N]10[(PW11FeO39)2O]·3.5H2O (1), [(C2H5)4N]10[(PW11FeO39)2O]·3H2O (2) and [(CH3)4N]10[(PW11FeO39)2O]·4H2O (3) were synthesized and characterized by elemental analysis, TGA-DSC, FT-IR, UV–vis and SEM. The catalytic activities of them were detected in the oxidation of cyclohexanol with H2O2 as oxidant. 1 with the longest carbon chain of organic countercations showed the best catalytic activity and exhibited a reaction-controlled phase transfer behavior. Many kinds of alcohols can be also efficiently oxidized into corresponding aldehydes or ketones based on 1. The fresh catalyst, the recovered one and the catalyst 1 treated with H2O2 were characterized by IR, UV and MALDI-TOF mass spectroscopy. The results manifested that the dimeric 1 decomposed into monomeric [C16H33(CH3)3N]4PW11Fe(H2O)O39·H2O (4) after the reaction. The temperature and H2O2 had an influence on the dimer-monomer transformation process. With the addition of H2O2, the solubility of 1 in the reaction solution was enhanced and 1 gradually decomposed into 4 with the temperature increasing, until decomposed completely at high temperature (70, 80 and 90 °C), eg., the dimer-monomer transformation completed at the first 3 h of the reaction at 70 °C. The mechanism of 1-catalyzed oxidation of cyclohexanol system with H2O2 was mainly a radical-chain mechanism. It was found that a faster reaction rate was observed during the transformation process based on 1 compared to 4 at the same amount of Fe in the catalyst. This suggested that there should exist the equilibrium of [(PW11FeO39)2O]10−, [PW11Fe(OH)O39]5- and [PW11Fe(H2O)O39]4- anions during the transformation process based on the radical decomposition of H2O2, which all played a catalytic role in the oxidation of cyclohexanol. But after the transformation, the [(PW11FeO39)2O]10- anion entirely decomposed into [PW11Fe(H2O)O39]4- anion until the reaction ended.

Rapid reduction of postprandial blood glucose is very beneficial to diabetics. In order to shorten the onset time of recombinant insulin, the cone snail insulin G1 (cI G1) of Conus geographus was studied. First, the nucleotide sequence of recombinant cone snail proinsulin G1 (cPI G1) was designed and synthesized according to the genes of human proinsulin (hPI) and cPI G1. The codon was optimized according to Escherichia coli (E. coli) codon usage frequency. Then, the plasmid pET22b(+)-cPI G1 was constructed and the recombinant cPI G1 was expressed in E. coli BL21(DE3) host strain. The recombinant cPI G1 was then purified and cleaved specially by trypsin to generate the recombinant cI G1, and its potency is 25.9 IU/mg. Fasting blood glucose test (FBGT) and oral glucose tolerance test (OGTT) suggested that the recombinant cI G1 could rapidly reduce blood glucose in normal and streptozotocin (STZ)-induced diabetic mice, but only for a short duration. This study provides a technical reference for the development of recombinant fast-acting insulin.为缩短重组胰岛素起效时间，达到快速降低餐后血糖的作用，以圆锥芋螺胰岛素G1 (cI G1) 为研究对象，参照人胰岛素原 (hPI) 和圆锥芋螺胰岛素G1 原 (cPI G1) 基因设计重组cPI G1 的核苷酸序列，按照大肠杆菌Escherichia coli 密码子使用频率进行密码子优化后构建pET22b(+)-cPI G1 质粒，以E. coli BL21(DE3) 菌株为宿主进行原核表达，获得重组cPI G1 蛋白，经胰蛋白酶切割及纯化得到重组cI G1，其效价为25.9 IU/mg。空腹血糖测试 (FBGT) 和葡萄糖耐量实验 (OGTT) 表明，cI G1 可迅速降低正常和链脲佐菌素 (STZ) 致糖尿病模型小鼠的血糖，但持续时间短，研究结果为重组速效胰岛素的开发提供参考。.

Regarding poly(vinyl alcohol)/silicotungstic acid (PVA/H 4 SiW 12 O 40 ) gel as precursor, the silver nanoparticles (NPs) were selectively deposited on the surface of the PVA/H 4 SiW 12 O 40 nanofibers by using electrospinning and photoreduction methods. X-ray photoelectron spectroscopy, Fourier transformation infrared spectroscopy, and UV–vis diffuse reflectance spectroscopy were used to affirm the structure and formation of tri-component nanohybrids. Field environmental scanning electron microscope and transmission electron microscopy indicate that the average diameter of silver NPs was changed from 25 nm to 50 nm, with decreasing the relative concentration of SiW 12 in the as-electrospun nanofibers. The nanocomposites exhibit excellent photocatalytic activity in degradation of Rhodamine B. This result arises from the synergistic effects and the large specific surface areas of Ag/PVA/H 4 SiW 12 O 40 tri-component nanohybrids.

Regarding gel poly (vinyl alcohol)/H 3 PW 12 O 40 as precursor, the ultra-fine fibers tungsten oxide (WO 3 ) was prepared by using electrospinning and calcinating techniques. Scanning electron microscope (SEM) shows that the average diameter of fibrous WO 3 were changed from 200 nm to 600 nm after calcined PVA/H 3 PW 12 O 40 fibers at 600 and 800 °C, respectively. X-ray diffraction (XRD) and Raman spectroscope revealed that the fibrous WO 3 was monoclinic phase, and the band-gap energies were observed by UV–vis diffuse reflectance spectra. The small size WO 3 exhibits excellent photocatalytcic activity in degradation of Rhodamine B at 365 nm wavelength.

In this paper, fibrous membranes of poly(vinyl alcohol)/α-2-K 8 P 2 W 17 MO 61 (M = Co, Ni) were prepared by electrospinning technique. Calcining the fibrous membranes at 340 °C for 6 h, fibrous membranes of pure α-2-K 8 P 2 W 17 CoO 61 and α-2-K 8 P 2 W 17 NiO 61 were obtained, respectively. Fourier transformation infrared spectroscopy and X-ray diffraction showed that Dawson–Wells structure of the polyoxometalates was still remained in the fibrous membranes. Scanning electron microscopy images and diameter distribution curves of the fibrous membranes indicated that the average diameter of α-2-K 8 P 2 W 17 CoO 61 fibers was about 145 nm, and α-2-K 8 P 2 W 17 NiO 61 about 168 nm. The magnetic property of the fibrous membranes was investigated.

Polyaniline/Prussian blue micro-composites have been synthesized by a low-temperature hydrothermal process. Prussian blue is obtained using the single iron-source precursor K 3 [Fe(CN) 6 ] in acidic aqueous solution. The composite was characterized by field-emission scanning electron microscopy (FE-SEM), Fourier transmission infrared spectroscopy (FT-IR), and X-ray diffractometer (XRD). The magnetic behavior of polyaniline/Prussian blue composites and the effect of the concentration of K 3 [Fe(CN) 6 ] on the morphology of polyaniline/Prussian blue micro-composites have been investigated.

Different morphologies of α-Fe 2 Ο 3 crystals including snowflake-like, paired microplates, dumbbell, column, and spindle microstructures have been prepared though a hydrothermal reaction in K 3 [Fe(CN) 6 ] solution with different pH values at 140 °C. The influences of the experimental conditions, such as pH value and reaction time on the morphologies of the as-prepared α-Fe 2 Ο 3 crystals, have been studied. The morphologies and structures of the α-Fe 2 Ο 3 crystals have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Selected-area electron diffraction confirms that the snowflake-like microstructure and paired microplates grow along the [001] direction, respectively. A possible growth process of α-Fe 2 Ο 3 crystals with varied morphologies from sixfold snowflake-like to the column-like microstructure has been proposed. Additionally, magnetic investigations show that the α-Fe 2 Ο 3 crystals with column-like microstructures exhibit a weakly ferromagnetic property at room temperature.

Thin film containing highly ordered silver nanowires array was prepared by using anodic aluminum oxide (AAO) template method. The morphology of the silver nanowires was confirmed by scanning electron micrograph (SEM). The result of the SEM showed that the silver nanowires were substantive, parallel, and ordered in the AAO template. Diameter distribution of the silver nanowires indicated that the average diameter was about 35 nm. The composition and structure of the Ag nanowires were investigated by Energy dispersive X-ray (EDX) spectroscopy and X-ray diffraction (XRD) pattern, respectively.

To investigate the effect of selenopeptide on phagocytosis, NO and H2O2 secretion of mouse peritoneal macrophages.Mouse peritoneal macrophages induced by lipopolysaccharide (LPS) were cultured for 24 hours by various concentrations of Se-ZnCu-65P, which is a selenopeptide with double antioxidant activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx). Then, the relative cell activity was determined by methyl thiazolyl tetrazolium (MTT) assays, the phagocytic ability of macrophages was evaluated by neutral red uptake assay, nitric oxide (NO) content was examined by nitrate reductase method, and hydrogen peroxide (H2O2) content was detected by molybdate colorimetric method.When Se-ZnCu-65P acted on macrophages alone, the relative cell viability was enhanced, the phagocytic ability was not affected, H2O2 content was reduced, and NO level was almost unchanged. However, the phagocytic ability of macrophages induced by LPS was raised, meanwhile, secretion of NO and H2O2 was promoted. When Se-ZnCu-65P acted on macrophages induced by LPS, the phagocytic ability were further enhanced, and secretion of NO and H2O2 was inhibited significantly.Se-ZnCu-65P can effectively improve the relative cell activity of mouse peritoneal macrophages induced by LPS, enhance the phagocytic ability of macrophages, and reduce the secretion levels of NO and H2O2.

In this paper, polyaniline (PANI) microfibers with average diameter of 250 nm were synthesized by utilizing H 4 SiW 12 O 40 /polyacrylamide (HPA/PAM) microfibers seeding template method. The PANI microfibers were characterized by element analyses, FT–IR spectra, X-ray diffraction pattern (XRD), and Scanning electron micrograph (SEM). The microfibers seeding template significantly affected the fibrous morphology of the resulting PANI. However, the diameter of the PANI microfibers was almost not affected by the diameter of the microfibers seeding template in the experimental range. In addition, the conductivity of the PANI microfibers was also investigated. The result showed that the best conductivity of the PANI microfibers doped with H 4 SiW 12 O 40 was 27.1 S/cm.