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The biosafety and biocompatibility after implantation of the transcutaneous energy transfer system of artificial anal sphincter is verified by combining simulation and experiment in this paper. The biosafety study is based on the simulation of bioelectromagnetic radiation experiment and the thermal rise during the charging period while the biocompatibility study is based on the coloration experiment of the tissue around the energy supply system during the in vivo experiment. The results of biosafety indicate that the transcutaneous energy transfer system performs excellently in bioelectromagnetic safety in the experimental environment with a resonance frequency of 110 kHz and an output power of 10 W. In addition, the local specific absorption rate is far below the international human electromagnetic safety standard. After 30 minutes of fast charging, the system temperature increases by 2.81 ℃, which is lower than the temperature threshold of 4.8 ℃, demonstrating the outstanding biothermal safety of the system. The section staining experiment of the wireless energy supply system indicates that the poly-ether-ether-ketone (PEEK) shell can significantly reduce immune rejection and improve the biocompatibility of the system.

Understanding bacterial adsorption and the evolution of biofilms on arsenopyrite with different surface structures is of great significance to clarifying the mechanism of microbe-mineral interfacial interactions and the production of acidic mine drainage impacting the environment. In this study, the attachment of Sulfobacillus thermosulfidooxidans cells and subsequent biofilm formation on arsenopyrite with different surface structures in the presence of dissolved As(III) was studied. Arsenopyrite slices with a specific surface were obtained by electrochemical corrosion at 0.26 V. The scanning electronic microscopy-energy dispersion spectra analyses indicated that the arsenopyrite surface deficient in sulfur and iron obtained by electrochemical treatment was not favorable for the initial adsorption of bacteria, and the addition of As(III) inhibited the adsorption of microbial cells. Epifluorescence microscopy showed that the number of cells attaching to the arsenopyrite surface increased with time; however, biofilm formation was delayed significantly when As(III) was added.

Photocatalysts with the photocatalytic “memory” effect could resolve the intrinsic activity loss of traditional photocatalysts when the light illumination is turned off. Due to the dual requirements of light absorption and energy storage/release functions, most previously reported photocatalysts with the photocatalytic “memory” effect were composite photocatalysts of two phase components, which may lose their performance due to gradually deteriorated interface conditions during their applications. In this work, a simple solvothermal process was developed to synthesize Bi2WO6 microspheres constructed by aggregated nanoflakes. The pure phase Bi2WO6 was found to possess the photocatalytic “memory” effect through the trapping and release of photogenerated electrons by the reversible chemical state change of W component in the (WO4)2− layers. When the illumination was switched off, Bi2WO6 microspheres continuously produced H2O2 in the dark as those trapped photogenerated electrons were gradually released to react with O2 through the two-electron O2 reduction process, resulting in the continuous disinfection of Escherichia coli bacteria in the dark through the photocatalytic “memory” effect. No deterioration of their cycling H2O2 production performance in the dark was observed, which verified their stable photocatalytic “memory” effect.

For many applications, polyurethanes (PU) need to have a fast curing speed but long pot life. Latent catalysts are seen to be one of the approaches that can fulfill the need. In this article, we ha...

Immobilization of radioiodine is a significant requirement for future nuclear fuel development. This research mainly focuses on the production of iodosodalite through a novel preparation method and the effect of boron on zeolite-4A immobilization of iodine waste forms. Through this novel way, the phase mass of iodosodalite can reach to 95.5% at 1050 °C and the rest is nepheline. The addition of B2O3 promotes the formation of iodosodalite at a lower sintering temperature and the phase mass of iodosodalite for the sample sintered at 1050 °C is 93.7% which is due to part of iodosodalite’s transformation into amorphous phase under the addition of B2O3. The existence of amorphous phase is proved by FTIR and SEM results. The EDS analysis reflects that Na, Al, Si, O and I elements are distributed homogeneously on the surface. The leaching rate of iodine proves considerable chemical durability of iodosodalite prepared through this novel method. Our finding provides a novel way to synthesis iodosodalite and is aimed to immobilize iodine waste forms.

A silicalite-1-based catalyst with highly dispersed manganese and iron oxides was synthesized by the wet impregnation method for the selective catalytic reduction (SCR) of NOx with NH3 at low temperatures. The optimized catalyst demonstrated over 90% NOx conversion efficiency between 135 and 270 °C with a space velocity of 35 000 h−1, which can be attributed to the well-developed porous structure of silicalite-1 and the synergistic effects between silicalite-1 and supported metal oxide active sites. In addition, the porous structure and the addition of FeOx greatly promoted the dispersion of MnOx nanoparticles, which further improves the efficiency of SCR. Moreover, the reaction route for the NH3-SCR reaction was further investigated by in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). The corresponding test results indicate that the reaction route follows both Eley–Rideal (E–R) and Langmuir–Hinshelwood (L–H) mechanisms.

Powdery photocatalyst has shown great potential in wastewater treatment, yet the low reusability is still its deficiency. In this work, we prepared magnetically recyclable lanthanum-nitrogen co-doped titania/CaFe 2 O 4 /diatomite (LN-TCD) ternary material by sol-gel technology. The photocatalytic activity of this material was evaluated via the decomposition of antibiotic oxytetracycline and disinfection of bacteria Escherichia coli under visible light. Charge transfer took place at the interface between titania and CaFe 2 O 4 , and improved the photocatalytic activity. The photodecomposition rate was accelerated by the high adsorption ability of substrate diatomite. The optimal preparation and experimental factors were determined, and the decomposition mechanism was proposed.

The sodium superionic conductor (NASICON)-type Na3V2(PO4)3 (NVP) with 3D framework is a promising candidate in sodium ion batteries. Plenty of subsequent modification methods are reported. However, the research of selection of carbon resources is few investigated. To explore the significant effects of different carbon resources on the sodium storage property of NVP system, herein, two kinds of carbon resources, such as citric acid and oxalic acid, are chosen to prepare the carbon coated NVP/C system utilizing a facile sol-gel route. The effects of different raw materials on the crystal structure, morphological features, kinetic characteristics and electrochemical property are deeply explored. The results demonstrate that the optimized NVP/C composite generated by citric acid possesses a larger crystal cell volume and a smaller particle size morphology, which brings the favorable expanded channel and shortened pathway for Na+ migration, resulting in superior kinetic characteristics. Accordingly, the citric acid induced NVP/C electrode exhibits a significantly improved sodium storage property. As a consequence, it delivers a high capacity of 112.3 mAh g−1 at 0.1 C. The retention ratio is nearly 100% cycled at 1 C rate after 200 cycles. Favored by the rapid electron and ion transfer, distinct reversible capacities of 90.0 and 89.1 mAh g−1 are obtained at 2 and 5 C rate, accompanied by high retention of 92.7% and 90.0% after 200 cycles. Therefore, this modified NVP/C material is a promising cathode for practical applications.

The immobilization of iodine waste is a challenge in the field of nuclear waste. In this work, iodine waste (silver-coated silica gel with different iodine loadings) was immobilized at low-sintering temperatures (500, 550, and 600 ​°C). XRD represented that the crystallized phases of the sintered matrix consist of AgI and B2O3. The crystallization behavior of boron can be found as the sintering temperature increased from 500 ​°C to 600 ​°C. FT-IR results proved that in the process of crystallization, part of the microstructure related to B–O stretching transformed from [BO4] to [BO3] units, which benefits low-temperature iodine waste immobilization due to the bonding energy of [BO3] is higher than that of [BO4]. Our work reveals the B-related microstructure transition in low-temperature immobilization iodine waste.

The gradient-structure is ideal nanostructure for conversion-type anodes with drastic volume change. Here, we demonstrate an inorganic-organic competitive coating strategy for constructing gradient-structured ferroferric oxide-carbon nanospheres, in which the deposition of ferroferric oxide nanoparticles and polymerization of carbonaceous species are competitive and well controlled by the reaction thermodynamics. The synthesized gradient-structure with a uniform size of ~420 nm consists of the ferroferric oxide nanoparticles (4–8 nm) in carbon matrix, which are aggregated into the inner layer (~15 nm) with high-to-low component distribution from inside to out, and an amorphous carbon layer (~20 nm). As an anode material, the volume change of the gradient-structured ferroferric oxide-carbon nanospheres can be limited to ~22% with ~7% radial expansion, thus resulting in stable reversible specific capacities of ~750 mAh g−1 after ultra-long cycling of 10,000 cycles under ultra-fast rate of 10 A g−1. This unique inorganic-organic competitive coating strategy bring inspiration for nanostructure design of functional materials in energy storage., The gradient-structure is ideal nanostructure for conversion-type anodes with drastic volume change. Here, the authors demonstrate an inorganic-organic competitive coating strategy to construct gradient-structured Fe3O4@C nanospheres.

The nanotube array-like WO3 (WA) photoanode has been widely utilized in solar-driven photoelectrocatalytic applications due to its excellent light absorption. However, it still suffers from a low quantum efficiency. Herein, double oxygen-evolution catalyst (OEC) layers (FeOOH and NiOOH) were deposited onto the surface of WA with the formation of a WA-FeOOH/NiOOH photoanode (WA-FeNi). The FeOOH greatly decreased the WA/OEC interfacial electron–hole pair recombination rate, while the NiOOH reduced the OEC/electrolyte interfacial electron–hole pairs recombination and promoted the composite’s water oxidation activity significantly. The as-formed WA-FeNi photoanode possessed a photocurrent density of 120 μA/cm2 under simulated sunlight irradiation, which is almost 200% that of WA. The electron–hole separation yield at 0.6 V versus SCE in the former was determined to be 39.3%, which is nearly 2.5 times that of the latter. As a result, the photoanode exhibited superstrong simulated-sunlight-driven photoelectroca...

Controlled introduction of oxygen vacancies in metal oxide based photocatalysts could improve their charge carrier separation efficiencies to enhance their photocatalytic performances. In this work, oxygen vacancies were introduced in Bi2MoO6 nanosheets through a postsynthesis etching treatment by NaOH aqueous solution at room temperature for the first time, which removed the requirement of high temperature treatment, chemicals of high cost and environmental hazardness, or specific apparatus for the introduction of oxygen vacancies in previous studies. Furthermore, the crystal structure, morphology, optical properties, and energy band structures of these Bi2MoO6 nanosheets were not changed by this approach, which allowed the separation and illustration of the charge carrier separation role of oxygen vacancies for the photocatalytic performance enhancement. With the increase of oxygen vacancies, Bi2MoO6 nanosheets demonstrated improved electron–hole separation efficiency and largely enhanced photocatalytic...

Monoclinic wolframite Ni1-xCoxWO4 (x = 0 and 0.15) nanosheets are synthesized successfully through chemical co-precipitation. The specific surface area increases appreciably with reduced pore radius when Co2+ ions are incorporated into the NiWO4 lattice. In comparison with NiWO4, the band gap of Ni0.85Co0.15WO4 reduces with the electrical conductivity increased threefold. The electrochemical properties and the device performance of supercapacitors with Ni1-xCoxWO4 as electrodes are characterized via the potentiostatic and galvanostatic cycle measurements, and electrochemical impedance spectroscopy (EIS). The Ni0.85Co0.15WO4 electrode exhibits an obvious increase in specific capacitance, six-fold higher than that of NiWO4 electrode at a current density of 0.5 A g−1. Ni0.85Co0.15WO4 electrode also shows excellent rate performance with ~78% capacitive retention while the current density is enhanced fivefold. The possible mechanism for the improved electrical conductivity and capacitive performance due to the incorporation of Co2+ to NiWO4 lattice has been discussed.

Protein crystallization is of great importance because protein crystals have a number of different important applications, including large-scale purification of proteins, determination of protein structure, nanoparticle preparation, and theoretical studies of crystallization. An approach often used to efficiently crystallize proteins is the use of nucleants or seeds (small fragments of protein crystals) that can help increase the probability of protein crystallization. Due to the very positive effect that seeding has on protein crystallization, seeds are now widely accepted and utilized in practical protein crystallization. Here, we show that cross-linked protein crystals (CLPCs), which retain the crystal structure but are much more stable than non-cross-linked crystals, can also be used as a new type of seed for promoting protein crystallization. Seeding with CLPCs has effects on both the reproducibility and screening of protein crystals and could improve the optical perfection (well-defined facets) of p...

Knowledge of the catalytic performances of different crystalline phases of a material is vital for the development of superior catalysts. In this study, different phases of MnO2 (α, β, γ, and δ) have been prepared by the oxidation of Mn2+, and their catalytic performances were evaluated using the aerobic oxidation of benzyl alcohol to benzaldehyde as a model reaction. α-MnO2 promoted the reaction to the highest yield. However, when the yields were normalized by the corresponding surface areas, δ-MnO2 exhibited the highest specific activity and α-MnO2 the lowest, indicating that the diverse microstructures resulting from the crystalline phase have a profound effect on catalytic performance. α-MnO2 showed the highest catalytic stability, resulting from its unchanged composition and morphology after use. Informed by the experimental results, a possible reaction mechanism involving the Mars-van Krevelen process was proposed. This work provides useful information for the development of effective catalysts for aerobic oxidation.

This article presents as follows the most recent progresses of our group on in-situ characterization and evaluation of the molecular mechanisms of interfacial interaction of minerals and bioleaching microorganisms. (1) By studying the speciation transformation of iron/copper/sulfur on the mineral surface, the evolution of cell surface properties and EPS composition, the evolution of microbial community structure, and the evolution of expression of key oxidase genes during bioleaching, to characterize the adaptation process and therein the effects of it on the specific sulfur oxidation efficiency of bioleaching; (2) by in-situ characterization of the evolution of chalcopyrite surface microstructure, chemical speciation and the biofilm formation, to illustrate the specific adsorption and the relationship between cell growth/biofilm formation and the structure and speciation on the defect mineral surface; (3) by studying the utilization, transformation and activation of S0, which is one of the major intermediates during bioleaching, and the distribution of extracellular thiol groups and iron speciation, to evaluate in situ the sulfur activation mechanism; and (4) by comparative proteomics study of the extracellular and outmembrane proteins and looking up the genome sequence, to screen sulfur activation/transportation relevant proteins and genes.

We have proposed a rational strategy for selecting a suitable pH of protein solution based on protein biochemical properties. However, it is difficult to use this strategy for biochemical properties unknown proteins. In this paper, a simpler and faster pH buffer strategy was proposed. An additional pH-controlling buffer was added to crystallization droplet mixed with protein solution and commercial crystallization reagents to adjust its pH. The results revealed that protein crystallization success rates were enhanced by this strategy due to expansion of the pH screening space, which was closely related with protein solubility. Thus, the possibility of reaching supersaturation was increased by using this strategy.

Layer-by-layer (LbL) assembly technique has been proven to be a convenient and eco-friendly method to obtain multifunctional coatings. In this research we presented a hydrophilic and transparent coating on various types of substrates by layer-by-layer deposition of polyvinylamine (PVAm) and dopamine-modified hyaluronic acid (HA-DN). The successfully constructed multilayers on gold surface were monitored by quartz crystal microbalance (QCM). The coating significantly improved the hydrophilicity of glass, stainless steel, gold, and polyvinyl chloride (PVC) surface as compared with the unmodified ones, which can reduce the water contact angle of the substrates by 30% to 45%. The growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was significantly inhibited on LbL-coated PVC, and 6 bilayers of coating can achieve nearly 100% suppression of bacterial growth. The coating was with no toxicity to mouse lymphocytes in polystyrene (PS) cell culture plate, while it significantly attenuated the viability of Michigan cancer foundation – 7 cells (MCF7) and human acute monocytic leukemia cell line (THP-1) in vitro. Therefore, this hydrophilic, transparent, antibacterial, biocompatible, and tumor-cell-suppressive coating would have broad potential in biomedical applications.

Regulating anode structure and component are necessary to the operation of the microbial electrochemical system (MES). In this work, graphene-based amino modification carbon nanotubes composite aerogel is prepared through simple hydrothermal reduction method. It is proved that the three-dimensional (3D) structure can provide a plenty of sites for microorganisms growth. The carbon nanotubes inserted in the graphene sheets can provide more paths for electron conduction in the anode and can enhance the electron transfer process. The introduction of amino groups promote the population of Geobacter in anode biofilm and further enhance the performance of the system. The maximum power density of the MES equipped with the composite anode can reach 944.3 W m−3, higher than previously reported high-output MESs with 3D graphene-based anodes. Meanwhile, the maximum current density of the system (2637.8 A m−3) increases 39.9% compared to the control anode system (1586.3 A m−3). The graphene-based amino modification carbon nanotubes composite anode in this study shows great potential for enhancing the performance of MES.

Protein crystallizes at specific conditions (correct precipitants, appropriate concentrations of protein and precipitants, suitable pH and correct temperature, etc.). If the conditions are not appropriate, crystallization will not occur. In protein crystallization screening, the target protein is mixed one by one with many chemical agents and then incubated at a set temperature. If the concentrations of the chemical agents and the target proteins are not in a range suitable for crystallization, the crystallization will not occur. To expand the concentration screening space, we propose in this paper a new design of protein crystallization plates for cross-diffusion microbatch and microbatch methods. The new plates have 96 units corresponding to the conditions of the commercial screening kits, and each unit contains four wells for holding the crystallization droplets. By dispensing crystallization droplets to the four wells at different volume ratios of protein to precipitant solutions, we can obtain four d...

Environments with varying temperatures have been shown to beneficially increase the probability of obtaining protein crystals. Therefore, a cycling temperature strategy (CTS) has been proposed for protein crystallization screening. During the practical application of this strategy, it is necessary to know the effective temperature range that promotes crystallization to design a suitable temperature program. In this paper, the effects of different temperature ranges on lysozyme crystallization (or more specifically, nucleation) were investigated. The results show that a small periodic variation in the temperature range of as little as 0.4 K can have a significant effect on the crystallization success rate under some crystallization concentration conditions, confirming that crystallization of lysozyme is very sensitive to temperature variation. Because practical protein crystallization is always performed in an environment with slight temperature variations, the sensitivity of protein crystallization to temperature may provide an explanation for the poor reproducibility of protein crystallization. Further investigation of the CTS on lysozyme crystallization showed that a cycling temperature strategy exerts an effect on protein crystallization by altering the supersaturation caused by changes in temperature.

Taking advantage of the self-assembly between the components, novel stable antibacterial nanoparticles were efficiently fabricated via a facile one-step co-polymerization of acrylic acid (AA) and N,N'-methylenebisacrylamide (MBA) on a mixed aqueous solution of poly(hexamethylene guanidine hydrochloride) (PHMG) and hydroxyethylcellulose (HEC). The z-average hydrodynamic diameters of the nanoparticles ranged from 220 nm to 450 nm. The inner layer of the nanoparticles is composed of water-insoluble interpolymer complexes of PHMG and PAA networks, while the outer layer is composed of PHMG and HEC. The nanoparticles are stabilized by electrostatic interactions, hydrogen bonding interactions, and the chemical bonds. The nanoparticle solution remained stable in a wide pH range of 2.0-12.0 and at salt concentrations below 0.25 mol/L. The nanoparticles were incorporated into handsheets using a dipping treatment. The resulted handsheets exhibited excellent antimicrobial activities even after multiple water washing treatments. The nanoparticles are promising in fabricating paper, water-based coatings and textiles with permanent antibacterial activity.

Bio-based unsaturated poly(butylene adipate-co-butylene itaconate) (PBABI) aliphatic copolyesters were synthesized with pentaerythritol (PE) as a modifier, observing the melting point, crystallization, and glass transition temperatures were decreased from 59.5 to 19.5 &deg, C and 28.2 to &minus, 9.1 &deg, C as an increase of itaconate concentration, and Tg ranged from &minus, 54.6 to &minus, 48.1 &deg, C. PBABI copolyesters tend to the amorphous state by the existence of the BI unit above 40 mol%. The yield strength, elongation, and Young&rsquo, s modulus at different BA/BI ratios were valued in a range of 13.2&ndash, 13.8 MPa, 575.2&ndash, 838.5%, and 65.1&ndash, 83.8 MPa, respectively. Shear-thinning behavior was obtained in all BA/BI ratios of PBABI copolyesters around an angular frequency range of 20&ndash, 30 rad s&minus, 1. Furthermore, the thermal and mechanical properties of PBABI copolyesters can be well regulated via controlling the itaconic acid contents and adding the modifier. PBABI copolyesters can be coated on a 3D air mesh polyester fabric to reinforce the mechanical property for replacing traditional plaster applications.

Manganese and iron oxides catalysts supported on silicalite-1 and titanium silicalite-1 (TS-1) are synthesized by the wet impregnation method for the selective catalytic reduction (SCR) of NOx with NH3 (NH3-SCR), respectively. The optimized catalyst demonstrates an increased NOx conversion efficiency of 20% below 150 &deg, C, with a space velocity of 18,000 h&minus, 1, which can be attributed to the incorporation of Ti species. The presence of Ti species enhances surface acidity and redox ability of the catalyst without changing the structure of supporter. Moreover, further researches based on in situ NH3 adsorption reveal that Lewis acid sites linked to Mn4+ on the surface have a huge influence on the improvement of denitration efficiency of the catalyst at low temperatures.

The use of thiosulfate salt (S2O32−), a low-cost reductant, as an absorbent for NO2 removal has been rarely reported. In this study, we propose a method that combines ozone oxidation and (NH4)2S2O3/steel slag slurry spraying to simultaneously remove sulfur dioxide (SO2) and nitrogen oxides (NOx) from flue gas. We investigated the effects of operation conditions on the simultaneous removal efficiencies of SO2 and NOx. Results showed that SO2 removal efficiency was affected by pH, whereas NOx removal efficiency was mostly influenced by (NH4)2S2O3 concentration, reaction temperature, and pH level. Under optimal operation conditions, removal efficiencies of almost 100% for SO2 and above 78.0% for NOx were achieved. NH4+ in the steel slag slurry could tolerate high NO2− concentrations (up to 3.00 mol/L), and the co-existence of NH4+ and S2O32− had a significant synergistic effect on NOx removal. Together with S2O32−, Mg2+ that leached from the steel slag also had a synergistic effect on NO2 removal. We established the reaction mechanisms for NOx removal using (NH4)2S2O3/steel slag slurry. In this process, S2O32− acted as a reducing agent and an oxidation inhibitor of SO32−, thereby enhancing NO2 removal. Moreover, NH4+ inhibited the denitration product (NO2−) from decomposing into NO and NO2, thereby accelerating NOx removal.

The effect of the surface microstructure and chemical speciation of chalcopyrite on the attachment behaviors of thermoacidophilic archaeon Sulfolobus metallicus was evaluated for the first time by using integrated techniques including epifluorescence microscopy (EFM) and sulfur K-edge X-ray absorption near edge structure (S K-edge XANES) spectroscopy, as well as scanning electron microscopy with energy dispersive spectrometry (SEM/EDS) and Fourier transform infrared (FT-IR) spectroscopy. In order to obtain the specific surface, the chalcopyrite slices were electrochemically oxidized at 0.87 V and reduced at −0.54 V, respectively. The EFM analysis showed that the quantity of cells attaching on the mineral surface increased with time, and the biofilm formed faster on the electrochemically treated slices than on the untreated ones. The SEM-EDS analysis indicated that the deficiency in energy substrate elemental sulfur (S0) in the specific microsize of local defect sites was disadvantageous to the initial attachment of cells. The XANES and FT-IR data suggested that the elemental sulfur (S0) could be in favor of initial attachment, and surface jarosites inhibited the adsorption and growth of S. metallicus. These results demonstrated that not only the surface microstructure but also the chemical speciation defined the initial attachment behaviors and biofilm growth of the extreme thermophilic archaeon S. metallicus.

A new method had been developed for the preparation of fluorescent Magnesium doped carbon quantum dots (Mg-CQDs) by a simple mechanical ball milling a mixture of cellulose and Mg power. The Mg-CQDs were characterized by X-ray photoelectron spectroscopy, Fourier transform infrared, X-ray photoelectron spectroscopy, UV-vis spectra, Fluorescent emission spectra and Transmission electron microscopy. And the result showed that the prepared Mg-CQDs displayed high selective and sensitive detection of iron ions with a detection limit of 50 ppb. Moreover, the idea of mechanical ball milling provided a method of large-scale industrial production to carbon quantum dots (CQDs).

A facile approach was developed to prepare highly dispersed TiO2 nanoparticles with selected phase. The crystallization phase of the nanoparticles can be easily tuned from anatase to rutile by the dosage of hydrochloric acid in the reaction system. The crystallite size of the as-prepared anatase TiO2 nanoparticles was ca. 3.2 nm with high dispersion. A transparent TiO2 colloid was obtained by dispersing the as-prepared anatase TiO2 nanoparticles in deionized water without any organic additives added. The concentration of TiO2-H2O colloid can be as high as 1600 g/L. The optical transmittance of TiO2-H2O colloid with a low concentration was nearly 100% in the visible region. Furthermore, anatase TiO2 nanoparticles(TiO2-NPs) showed superior photocatalytic performance compared to rutile TiO2-NPs.

One well-known prerequisite for successful crystallization from solution is a supersaturated solution. To achieve supersaturation, many methods are known, among which solvent evaporation is a common approach. For protein crystallization, the most widely used method is vapor diffusion, in which solvent evaporation from the crystallization solution is the major reason for achieving supersaturation. The solvent evaporation rate may affect the actual concentration distribution in the crystallization solution, thereby influencing the crystallization process. To explore the effect of evaporation rate on protein crystallization, we used lysozyme as a model protein and studied the crystallization success rate at different evaporation conditions. Successful crystallization occurred only when both supersaturation and evaporation rates were in suitable ranges. This study demonstrates that both supersaturation level and the rate of reaching supersaturation (or solvent evaporation rate) are important for lysozyme crystallization. To increase the chance of obtaining crystals, manipulation of solvent evaporation rate is one choice. According to this assumption, we performed crystallization screening trials at different evaporation rates using three model proteins. The trials demonstrate that control of the evaporation rate during crystallization may provide more opportunities to obtain crystals.

Cross-linked protein crystals (CLPCs) are very useful materials in applications such as biosensors, catalysis, and X-ray crystallography. Hence, preparation of CLPCs is an important research direction. During the preparation of CLPCs, an often encountered problem is that cracks may appear in the crystals, which may finally lead to shattering of the crystals into small pieces and cause problem in practical applications. To avoid cross-link induced cracking, it is necessary to study the cracking phenomenon in the preparation process. In this paper, we present an investigation on how to avoid cracking during preparation of CLPCs. An orthogonal experiment was designed to study the phenomenon of cross-link induced cracking of hen-egg white lysozyme (HEWL) crystals against five parameters (temperature, solution pH, crystal growth time, glutaraldehyde concentration, and cross-linking time). The experimental results showed that, the solution pH and crystal growth time can significantly affect cross-link induced cracking. The possible mechanism was studied, and optimized conditions for obtaining crack-free CLPCs were obtained and experimentally verified.

Al and S co-doped TiO2 (S-Al-TiO2) mesoporous materials as a kind of visible light photo- catalysts are prepared using pyridine as a template through a solid state reaction route. The materials features are characterized by the advanced instruments. The photodegradation kinetic of paclobutra- zol is investigated. It is shown that the doping of S and Al could effectively inhibit the growth of anatase TiO2, both S and Al have entered into the lattice of TiO2. Surface area of 81.3m2/g and narrow pore size distribution (~2.1nm) are presented, it not only enables the visible-light absorption but also promotes photocatalytic property of paclobutrazol. Moreover, within 150 min of visible-light irradiation, the photocatalytic degradation of paclobutrazol approximately follows an order kinetics, and the photodegradation rate in 46.7% and reaction rate constant of 0.00414 min-1 are obtained.

A novel nanohybrid was successfully fabricated by deposition of gold nanoparticles (AuNPs) onto the surface of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized bacterial cellulose nanofibers (TOBCNs). The prepared AuNPs/TOBCNs nanohybrids were characterized by UV-vis spectral analysis, XRD, TEM and HRTEM. Their catalytic activity for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) was estimated by UV-vis spectrometry. The results showed that the AuNPs/TOBCNs nanohybrids possessed AuNPs with an average diameter of 4.30±0.97nm exhibited superior catalytic properties for the reduction of 4-NP to 4-AP. The influences of the content of reducing agent and system temperature on the catalytic property were studied. Moreover, the turnover frequency of AuNPs/TOBCNs was 750h-1, which is higher than most recently reported AuNPs-based catalysts. This work reported a heterogeneous catalyst based on TOBCNs supported AuNPs with superior catalytic properties.

In the present work, the acidophilic and thermophilic strain Acidithiobacillus caldus was used for biodesulfurizing coal and bioleaching coal pyrite. The surface characteristics of cells and minerals and the mineral transformation during the coal pyrite leaching process were investigated combined with zeta-potential, FT-IR spectroscopy, scan electronic microscopy and X-ray absorption near edge structure spectroscopy (XANES). The results showed that the coal pyritic desulfurization with A. caldus was about 47% and the total desulfurization was 19%. After processed by cells, there was clear corrosion on the pyrite surface. Coal pyrite and elemental sulfur-grown cells had more hydrophilic functional groups than thiosulfate-grown cells. During the coal pyrite leaching course, the elemental sulfur was the main sulfur speciation but no other secondary mineral components were detected. (C) 2012 Elsevier B.V. All rights reserved.

Ag2Al intermetallic compound nanoparticles were synthesized by the flow-levitation method. The morphologies, granularity and phase structure were investigated by transmission electron microscope, X-ray diffractometer, and energy dispersive spectrometer. The results indicate that the prepared nanoparticles are regular spheres, with the grain size ranging from 20 to 110 nm. The nanoparticles are mainly composed of Ag2Al, including a little Al. The data of chemistry elementary analysis indicate that the atomic ratio of Ag to Al in the nanoparticles is about 66.5∶33.5. The grain size of Ag2Al in the prepared nanoparticles is about 33 nm, and that of Al is about 21 nm.

The adsorption-induced polymerization of 3-methylthiophene (3MT) on silver vapor-deposited glass surfaces is investigated using micro Raman scattering and UV–Vis reflection spectroscopy. Both techniques provide the evidence of an adsorption-induced polymerization mechanism of these molecules, indicating that the orientation of 3MT molecules randomly distributes in the bulk poly(3-methylthiophene) film. The kinetics of 3MT adsorption-induced polymerization is also studied using Auger electron spectroscopy. The adsorption-induced polymerization process shows constant adsorption rate (0.15 nm min−1) within adsorption time of 1 h. Moreover, the electroactive characteristics of P3MT are employed to detect uric acid in phosphate buffer solution.

Nanocomposites of poly (vinyl alcohol) and antimony-doped tin oxide (ATO) were prepared by solution blending. The PVA composites were characterized by FTIR, TGA, DSC, WXRD and stress-strain testing. It has been found that adding ATO to the matrix has great influence on the crystallization behavior and glass transition temperature of PVA. The mechanical properties of PVA changed with the filler content, exhibiting an initial increase in these properties due to polymer-filler interactions. After a maximum value, at about 5 wt%, the mechanical properties decreased. Thermal stability of the nanocomposites was found to be remarkably enhanced by the incorporation of ATO.

Photochromic nanofibers were fabricated by electrospinning the complex of cellulose acetate (CA)–1′,3′,3′-trimethyl-6-nitrospiro (2H-1-benzopyran-2,2′-indoline) (NO 2 SP) and their photochromic properties were investigated. The as-spun nanofibers were characterized by infrared spectra (IR) and the results showed a significant hydrogen bonding reaction between CA and NO 2 SP. Incorporated NO 2 SP was found to exert no effect on the nanofiber morphology. Through monitoring the color change and the water contact angle of the CA–NO 2 SP nanofibrous mat, the reversible photochromic property of the nanofibers was testified. The results of ultraviolet–visible (UV–vis) spectrophotometry and fluorescence microscopy indicated that NO 2 SP could endow electrospun fibers with good photochromic and fluorescent properties. Photochromic nanofibers with excellent photosensitivity have great potentials for the applications in optical devices and/or biosensors.

Varying the temperature has been proven to be beneficial for improving the screening efficiency of protein crystallisation, and thus a crystallisation screening strategy based on this phenomenon can be developed. Such a temperature varying strategy can be applied in practical crystallisation screening, however, there are no guidelines for determining what temperature programme should be utilised. It is therefore necessary to investigate how the temperature programme affects the crystallisation process, so as to help people design a suitable temperature programme. For this purpose, we investigated the effect of temperature programmes on the protein crystallisation (lysozyme, proteinase K, and concanavalin A) that are characterised by different solubility behaviours with respect to temperature. Judging from the reproducibility studies of protein crystallisation with different temperature programmes, we recommend using linear temperature programmes for a moderate time period (24 to 48 h) and a large temperature range according to the properties of the proteins. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Polypropylene (PP) microporous membranes were successfully prepared by swift heavy ion irradiation and track-etching. Polypropylene foils were irradiated with (197)Au ions of kinetic energy 11.4 MeV.u(-1) (total energy of 2245.8 MeV) and fluence 1x10(8) ions.cm(-2) at normal incidence. The damaged regions produced by the gold ions along the trajectories were etched in H(2)SO(4) and K(2)Cr(2)O(7) solutions leading to the formation of cylindrical pores in the membranes. The pore diameters of the PP microporous membranes increased from 380 to 1610 nm as the etching time increased from 5 to 30 min. The surface and cross-section morphologies of the porous membranes were characterized by scanning electron microscopy (SEM). The micropores in the membranes were found to be cylindrical in shape, homogeneous in distribution, and equal in size. Some mathematical relations of the porosity of the PP microporous membranes were established by analytic derivation. The microporous membranes were used in lithium-ion batteries to measure their properties as separators. The electrical conductivity of the porous membrane immersed in liquid electrolyte was found to be comparable to that of commercial separators by electrochemical impedance spectroscopy (EIS). The results showed that the porosity and electrical conductivity were dependent on the ion fluence and etching time. By adjusting these two factors, microporous membranes with good porosity and electrical conductivity were made that met the requirements for commercial use.

An advanced heat-resistant hyperbranched poly(phenylene sulfide) (HPPS) had been subjected to dynamic thermogravimetric analysis (TGA) in nitrogen. The presence of a single peak in the DTG cures suggested that weight loss occurs in a single stage. The thermal decomposition kinetics had been analyzed by applying the Kissinger, Friedman and Ozawa-Flynn methods. The E values determined for the hyperbranched PPS using these analyses were found to be 183.1, 189.2, 193.9 kJ mol−1, respectively. Coats-Redfern method was used to discuss the probable degradation mechanisms. The solid-state decomposition mechanism followed by the degradation stage of HPPS was Phase boundary controlled mechanism (R1). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009