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The development of efficient visible-light-driven photocatalysts remains one of the greatest scientific challenges of this century. In this paper, visible light active ZnO/Ag heterostructures have been synthesized on a large-scale by a simple one-pot synthesis method. The influence of the Zn/Ag ratio on the properties of heterostructures was investigated in detail. In light of the formation process of heterostructures, ZnO rods and Ag nanoparticles can link each other by strong bonds due to the bridging effect of NH3, which is found to be essential for the efficient visible-light-responsive activity and stability. These heterostructures were characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray fluorescence, Raman and UV-vis spectroscopy. These results indicate that ZnO/Ag composition is well-constructed with a band gap of 2.85 eV. Moreover, photocatalytic experiments show that these ZnO/Ag heterostructures are robust and exhibit high photocatalytic activity for the efficient separation of electron–hole pairs and the subsequent generation of hydroxyl radicals.

As a common monocomponent metal oxide, an α-MnO2 nanotube was synthesized by a simple hydrothermal method and developed as an ozonation catalyst for the first time. α-MnO2 nanotubes revealed excellent catalytic activity and stability for degradation of phenol in water. The strong interaction between ozone and α-MnO2 in water was observed and confirmed as a critical step of catalysis. The IR analysis and the influence of phosphate showed that the surface hydroxyl groups and chemisorbed water acted as the active sites in promoting active oxygen species, while Lewis acid sites were confirmed as reactive centers for catalytic ozonation in the aqueous phase. The ˙OH, O2˙−, *O2 and *O were not mainly involved in the catalytic ozonation of phenol based on the corresponding experimental results. According to the X-ray photoelectron spectroscopy (XPS) results, in the presence of α-MnO2, electrons from the surface Mn(III) were responsible for the catalysis and the oxidation of lattice oxygen enhanced the reversion of Mn(IV) to Mn(III). The balance between Mn(III)/Mn(IV) and O(–II)/O(0) was the primary factor for the catalytic performance of α-MnO2.

In this paper, the kinetics and interface sensitivity of nano-sized magnetic NiFe2O4 in incomplete catalytic ozonation were investigated in detail. By analyzing the kinetics of heterogeneous reactions, it was found that both the degradation of phenol and the decomposition of molecular ozone appeared to follow a first order kinetics model and the presence of nano-NiFe2O4 significantly enhanced these processes. The kinetics equations and reaction rate constants were determined according to experimental results. In light of the IR spectra, the Lewis acid sites were further confirmed as reactive centers for catalytic ozonation in the aqueous phase, and the reason for deactivation of the NiFe2O4 nanocatalyst during incomplete ozonation of organic compounds was determined. The catalytic activity of the NiFe2O4 nanocatalyst could be completely recovered by calcination and ozonation methods, which makes it an attractive nanomaterial with prospective applications in water treatment. According to the interface sensitivity of ozone in water, a strong interaction between ozone and NiFe2O4 was observed and the role of water was revisited. Water molecules were clarified as two different types: one is chemisorbed water on the catalyst surface and the other is bulk water in aqueous solution. Both bulk and chemisorbed water molecules should be weak competitors compared with ozone, and the chemisorbed water on the catalyst surface was proposed not as an inhibitor but an accelerator for catalytic activity.

Exploitation of efficient photocatalytic materials is a vital matter to settle the energy and environmental crisis we are facing. In this work, BiOCl with oxygen vacancy (OV-BOC) is synthesized by solvothermal modification method. According to the acquired DRS, VB-XPS, ESR results, solvothermal modification synthesis can not only introduce oxygen vacancy which supports the generation of 1O2 but regulate the band structure, giving rise to the valance band down-shift and hence the photogenerated h+ possesses higher oxidation capacity, which brings about desirable photodegradation efficiency on organic pollutants. It is unexpected that the degradation rate can be promoted by 2.6, 3.1 and 2.4 times after adding a little H2O2 towards rhodamine B, methyl orange and phenol, respectively, which benefits from the increased production of O2−. These increased O2− comes from activated H2O2 through the direct attack of holes which possesses higher oxidation capacity because of valance band down-shift H 2 O 2 + h + → • O 2 - + 2 H + , as certified by analyses of free radicals and band positions. Radical species capturing and ESR experiments are used to reveal the mechanisms involved by reactive oxygen species and the results show that h+, 1O2 and O2− species are all responsible for photocatalytic degradation. This study may give some guidance on architecting photocatalysts on band structure regulation and molecular oxygen activation simultaneously.

High concentration of 5-amino salicylic acid (5-ASA) in the distal ileum and colon is necessary for the treatment of inflammatory bowel disease (IBD). The control of small molecules, drugs, released from a polymeric matrix remains a great challenge.To study the preparation and properties of a pH-sensitive carrier for targeting delivery of 5-ASA.The carrier was prepared by ternary blends method based on polyvinyl alcohol (PVA), sodium alginate (SA) and polylactic acid. It was characterized by infrared spectrometry and scanning electronic microscopy. The adsorption and release of 5-ASA in different pH media were investigated.We found out the best ratio of the materials for synthetic carrier. The vector exhibited good performance by the controlled release of the target drug experiment. The adsorption capacity of the carrier for 5-ASA was 70.34% in phosphate buffer saline at pH 1.00, and the release rate was 100.49% in phosphate buffer solution at pH 6.80.PVA is vector backbone of the carrier, and SA plays key role in its pH performance. It is a promising material to effectively deliver 5-ASA to the specific sites of IBD.

A thermal desorption method with gas chromatography–mass spectrometry (TD–GC–MS) analysis was developed to directly profile the volatile organic compounds in Cinnamomum cassia(C. cassia) for the first time. The GC–MS conditions were optimized and internal electron ionization (EI) was used as the ionization method. The peaks were identified by comparing the obtained EI mass spectra with those of standard EI mass spectra in the National Institute of Standards and Technology mass spectral library. The relative contents of the volatile compounds were estimated by comparing the relative peak areas. Nine volatile organic compounds were identified and quantified. Cinnamaldehyde (E) was detected as the main compound in C. cassia and its relative content among the volatile components is estimated to be 72.7%. This developed method was compared with traditional hydrodistillation using a Clevenger-type apparatus for extraction prior to GC–MS analysis. The results shown that the total ion chromatogram (TIC) of TD–GC–...

A two-dimensional thin-layer chromatographic fingerprint has been developed on a polyamide plate for the quality control of Helleborus thibetanus Franch. The investigated sample was separated by chloroform-ethyl acetate-methanol (3.0:8.0:4.4, v/v) in the first dimension and isooctane-n-propyl alcohol-water (10:2.5:1.0, v/v) adding 0.28 mol L-1 sodium dodecyl sulfate, a reversed micelle, in the second dimension. The plate was dried in the air at room temperature and examined in ultraviolet (UV) light at lambda = 365 nm after development. The two developments were carried out over a distance of 70 mm. The two-dimensional thin-layer chromatographic method was validated in terms of repeatability, stability, and robustness. For fingerprint analysis, nine spots were identified as common spots. Statistical method (canonical correlation analysis) was first used to calculate the degree of similarity between the two-dimensional chromatograms. The proposed method was novel and accurate for the identification and quality evaluation of H. thibetanus Franch.

A novel Cu-Co-O composite nanocatalyst was designed and prepared for the ozonation of phenol. A synergistic effect of copper and cobalt was observed over the Cu-Co-O composite nanocatalyst, which showed higher activity than either copper or cobalt oxide alone. In addition, the Cu-Co-O composite revealed good activity in a wide initial pH range (4.11-8.05) of water. The fine dispersion of cobalt on the surface of copper oxide boosted the interaction between catalyst and ozone, and the surface Lewis acid sites on the Cu-Co-O composite were determined as the active sites. The Raman spectroscopy also proved that the Cu-Co-O composite was quite sensitive to the ozone. The trivalent cobalt in the Cu-Co-O composite was proposed as the valid state.

The mix of warm and hot recycled asphalt mixtures were determined after reclaimed asphalt mixture (RAP) analysis and mix design. With similar aggregate gradation, the RAP content in warm recycled asphalt mixture increased to 45%, guaranteeing good performance of the warm recycled mixture. Thus, the 30% RAP restriction in asphalt mixture was surpassed. The fatigue performance of the warm recycled asphalt mixture, its hot counterpart, and hot mix asphalt (HMA) was tested using the four-point bending test. The testing result indicates that, although the fatigue performance of warm recycled asphalt mixture is not as good as that of HMA, it is superior to that of the hot recycled asphalt mixture, especially at high strain levels. The fatigue life of warm recycled asphalt mixture is 1.5 times that of the hot recycled asphalt mixture.

This study reported a pH-mediated stacking CE coupled with ESI MS/MS method to determine the phosphorylation sites of three synthetic phosphopeptides containing structural isomers. These phosphopeptides mimic the phosphopeptides (amino acid residues 12-25) derived from the trypsin-digested products of human lamin A/C protein. The LODs were determined to be 118, 132 and 1240 fmol for SGAQASS(19)TpPL(22)SPTR, SGAQASS(19)TPL(22)SpPTR, and SGAQASS(19)TpPL(22)SpPTR, respectively. The established method was employed to analyze the phosphorylation sites of the trypsin-digested products of glutathione S-transferase-lamin A/C (1-57) fusion protein that had been phosphorylated in vitro by cyclin-dependent kinase 1. The results indicated that this method is feasible to specifically determine the phosphorylation site from phosphopeptide isomers in the trypsin-digested products of a kinase-catalyzed phosphoprotein, which should benefit the investigation of protein kinase-mediated cellular signal transduction.

In this study, a simple and amplified colorimetric assay is developed for the detection of the enzymatic activity of glucose oxidase (GOx) based on in situ formation of a photoswitchable oxidase mimetic of PO₄(3-)-capped CdS quantum dots (QDs). GOx catalyzes the oxidation of 1-thio-β-d-glucose to give 1-thio-β-d-gluconic acid which spontaneously hydrolyzes to β-d-gluconic acid and H₂S; the generated H₂S instantly reacts with Cd(2+) in the presence of Na₃PO₄ to give PO₄(3-)-stabilized CdS QDs in situ. Under visible-light (λ ≥ 400 nm) stimulation, the PO₄(3-)-capped CdS QDs are a new style of oxidase mimic derived by producing some active species, such as h⁺, (•)OH, O₂(•-) and a little H₂O₂, which can oxidize the typical substrate (3,3,5,5-tetramethylbenzydine (TMB)) with a color change. Based on the GOx-triggered growth of the oxidase mimetics of PO₄(3-)-capped CdS QDs in situ, we developed a simple and amplified colorimetric assay to probe the enzymatic activity of GOx. The proposed method allowed the detection of the enzymatic activity of GOx over the range from 25 μg/L to 50 mg/L with a low detection limit of 6.6 μg/L. We believe the PO₄(3-)-capped CdS QDs generated in situ with photo-stimulated enzyme-mimicking activity may find wide potential applications in biosensors.

A graphitic g-C3N4 based photocathode is prepared by dip coating a NiO-coated FTO (F-doped tin oxide) glass support in an aqueous solution of (NH2)2CS for 4 h followed by sintering under N2 (500 °C, 2 h).

A sensitive and simple method for the determination of melamine (MA) was developed based on the fluorescence enhancement effect of MA for thioglycolic acid-capped (TGA-capped) CdS quantum dots (QDs). Under optimum conditions, a good linear relationship was obtained from 2.0 × 10−9 to 5.0 × 10−5 M. The detection limit was 1.0 × 10−9 M, which was much lower than the safety limit (2.5 ppm in USA and the UK; 1 ppm for infant formula in China). The solution pH, the adding sequence of the buffer solution and MA and surface modifiers of CdS QDs greatly influenced the enhancement extent of MA for CdS QDs. The fluorescence enhancement was attributed to the surface passivation of the surface states of QDs by amine group of MA. The method was applied to detect MA in raw milk with satisfactory results. The proposed method manifested several advantages such as high sensitivity, short analysis time, low cost and ease of operation.

A kind of nanosized sulfated zirconia was prepared by a hydrothermal method, and full characterized by XRD, TEM, BET, TGA, and FTIR. Its catalytic activity was evaluated in the esterification reactions, including the testing of the catalytic reusability and the optimization of reaction conditions. The obtained catalyst was revealed to be highly efficient solid catalyst for the esterification of acetic acid with n-butanol, presenting the advantages of high conversion and selectivity, easy recovery, and steady reusability.

ZnO nanoparticles were synthesized through a facile route and were used as ozonation catalysts. With the increase of calcination temperature (150-300 o C), surface hydroxyl groups and catalytic efficiency of asobtained ZnO decreased remarkably, and the ZnO obtained at 150 o C showed the best catalytic activity. Compared with ozonation alone, the degradation efficiency of phenol increased above 50% due to the catalysis of ZnO-150. In the reaction temperatures range from 5 o C to 35 o C, ZnO nanocatalyst revealed remarkable catalytic properties, and the catalytic effect of ZnO was better at lower temperature. Through the effect of tertbutanol on degradation of phenol and the catalytic properties of ZnO on degradation of nitrobenzene, it was proposed that the degradation of phenol was ascribed to the direct oxidation by ozone molecules based on solidliquid interface reaction.

The degradation efficiencies of phenol in aqueous solution were studied by semi-continuous experiments in the processes of ozone alone, ozone/bulky Co 3 O 4 and ozone/Co 3 O 4 nanoparticles. Catalyst samples (bulky Co 3 O 4 and Co 3 O 4 nanoparticles) were characterized by X-ray diffraction and transmission electron microscopy. The Brunauer-Emmett-Teller surface area, pH pzc and the density of surface hydroxyl groups of the two catalyst samples were also measured. The catalytic activity of Co 3 O 4 nanoparticles was investigated for the removal of phenol in aqueous solutions under different reaction temperatures. Tert-butyl alcohol had little effect on the catalytic ozonation processes. Based on these results, the possible catalytic ozonation mechanism of phenol by Co 3 O 4 nanoparticles was proposed as a reaction process between ozone molecules and pollutants.

The novel mesoporous materials containing titanium and manganese, Ti-HMS (50) and Mn-HMS (50) (the number 50 denoting the Si/metal of molar ratio), were synthesized using laurylamine as template at room temperature. They were characterized by a series of techniques including powder XRD, FT-IR, UV–Vis spectroscopy, TEM, TG and Nitrogen physisorption. The results indicated that titanium and manganese had been incorporated into the HMS and both them had a wormhole mesopore structure. It also suggested that Mn2+ and Mn3+ coexisted in the Mn-HMS, Ti4+ in Ti-HMS. Besides, epoxidation of soybean oil over these synthesized catalysts was performed using tert-butyl hydroperoxide (TBHP) as oxidant. An increase in the activity was observed when surface area, pore diameter and hydrophobic nature were increased, which meant more active center reacting with soybean oil (SBO), also could reduce the energy barrier and avoid the oxirane ring opening. Furthermore, the result indicated that Mn-HMS showed a higher selectivity (up to 82.9% for Mn and 51.1% for Ti), but Ti-HMS exhibited a better conversion. The novel mesoporous materials containing titanium and manganese, Ti-HMS (50) and Mn-HMS (50), were synthesized. All catalysts was characterized by XRD, which suggested a single low-angle (100) peak at 2.3°

Quasi-monodisperse hydrophobic transition-metal ferrite MFe2O4 (M = Mn, Fe, Co, Ni, Zn) nanocrystals were synthesized by the thermolysis of transition-metal acetates in oleyl alcohol solutions under aerobic conditions. The proposed reaction protocol is simple, rapid, and highly versatile because it takes advantage of the multiple roles of the oleyl alcohol molecules, namely, solvent for the precursors, reaction medium, and capping ligand for the metal oxide nanoparticles. A systematic FT-IR spectroscopy study has indicated that the transition-metal ferrite nanoparticles are precipitated in oleyl alcohol solutions via a thermal decomposition process with no evidence about a potential esterification reaction, involving the long-chain alcohol and the metal acetate salt. A detailed characterization of the oleyl alcohol capped ferrite nanoparticles was performed by XRD, TEM, SAED, EXAFS, FT-IR, and SQUID measurements. The as-prepared transition-metal ferrite nanocrystals are spherically shaped, and their avera...

A series of new organometallic catalysts for epoxidized vegetable oils using H2O2 in a biphasic system were investigated. The effect of reaction parameters such as the amount of hydrogen peroxide, reaction time and temperature in the epoxidation of soybean oil are discussed in detail. A selectivity of 83.8% was obtained in 4 h at 60 °C, when [(C18H37)2N(CH3)2]3{PO4[WO(O2)2]4} was used as the catalyst. When methyltrioxorhenium (MTO), imidazole and CH3CN were used as the catalyst, adduct, and solvent respectively, a selectivity of 99.90% was achieved in 4 h at 20 °C. The catalytic system was used for the epoxidation of other oils, whose results showed it was active in the epoxidation of long-chain unsaturated compounds. Furthermore, the reaction of H2O2 with methyltrioxorhenium was studied by UV–Vis spectroscopy, which revealed the active peroxorhenium complexes formed during the reaction. Epoxidation of these oils with organometallic compounds occurred through the interactions between the oils unsaturated sites HOMO π(C–C) and the unoccupied peroxo σ*(O–O) orbital.

In this paper nanosized Co3O4/CeO2 was successfully synthesized by a simple hydrothermal method and was applied as catalyst in catalytic ozonation of phenol in solution. The observed results show that nanoparticles have a pleasant special surface. Ozonation experiments indicate that the nanoparticles present a certain catalytic effect on the degradation of phenol and a remarkable acceleration on the chemical oxygen demand removal. Further investigations reveal that a mechanism of solid–liquid interface reactions exists in this system.

The interaction between human immunoglobulin (HIgG) and BAFP (2,6-bis[4-(4-amino-2-trifluoromethyl phenoxy)benzoyl] pyridine was studied by fluorescence quenching, Fourier transform infrared (FT-IR) spectra and molecule modeling. The synchronous fluorescence spectra indicated the information on qualitative changes of the protein secondary structure in the presence of BAFP in aqueous solution. The quantitative alterations of the protein secondary structure were estimated by the evidences from FT-IR spectra with increases of a helices by about 2.6%-10.2%, increases of beta-sheet structure by about 13.6%-27.7%, and reductions of beta-turn structure by about 23.8%-30.3%. Molecular docking suggests that BAFP can strongly bind to HIgG. There are four hydrogen bond interactions between the drug and the residues Trp 170, Val 105, Met 139 and Asn 52. It was also considered that BAFP bound to HIgG mainly by a hydrophobic interaction, which is in good agreement with the results from the experimental thermodynamic parameters (the enthalpy change Delta H(circle minus) and the entropy change Delta S(circle minus)) were calculated to be -6.70 kJ.mol(-1) and 71.93 J.mol(-1).K(-1), respectively, according to the Van't Hoff equation).

Using Mn(NO 3 ) 2 and ozone as raw materials, β-MnO 2 nanowires with diameters of about 6–12 nm, lengths of 2–5 μm and surface area of 73.54 m 2 g −1 were synthesized by a simple hydrothermal process. The influences of synthesis conditions such as hydrothermal temperature, reaction time and ozone were investigated, and the growth process of β-MnO 2 nanowires was discussed. The catalytic properties of β-MnO 2 nanowires for the degradation of phenol were evaluated. β-MnO 2 nanowires revealed good separability and remarkable catalysis for the degradation of phenol.

Natural mineral brucite was used directly in catalytic ozonation of dye wastewater of active brilliant red X-3B. Compared with single ozonation, degradation of X-3B increased from 47% to 89%, and removal rate of COD increased from 9% to 32.5% in catalytic ozonation for 15 min. The catalytic ozonation of X-3B followed a direct oxidization mechanism by ozone molecule, and this was actually a homogeneous catalysis of OH− due to dissolution of Mg(OH)2 from natural brucite. As a natural mineral catalyst, brucite has supplied an economical and feasible choice for catalytic ozonation of X-3B in industrial wastewater.

In this work, magnesia from natural brucite mineral has been used firstly for catalytic degradation of nitrobenzene and aniline in presence of ozone. Compared with single ozonation, the catalytic ozonation accelerated markedly the degradation of nitrobenzene and aniline. The influences of hydroxyl radical scavengers, pH values, and reaction temperatures on degradation were investigated. It was found that the essential of catalysis was the homogeneous catalysis of hydroxyl ions in water, which accelerated the generation of hydroxyl radicals. As a catalyst, magnesia from natural brucite has supplied an economical and feasible choice for catalytic ozonation of nitrobenzene and aniline in industrial wastewater.

In this study, 3-(trimethoxysilyl)propyl methacrylate (γ-MPS), a bifunctional group compound, was used as a single cross-linking agent to prepare molecular imprinted inorganic-organic hybrid polymers by in situ polymerization for open-tubular capillary electro chromatography (CEC) column. The optimal preparation conditions were: the ratio between template molecule and functional monomer was 1:4; the volume proportion of porogen toluene and methanol was 1:1 and the volume of cross-linking agent γ-MPS was 69 μL. The optimal separation conditions were separation voltage of 15 kV; detection wavelength at 215 nm and background electrolyte composed of 70% acetonitrile/20 mmol/L boric acid salt (pH 6.9). Under the optimized conditions, the propranolol enantiomers can be separated well by CEC. The method is simple and fast, it can be a potentially useful approach for propranolol enantiomers separation.

In this work, we report a novel AgBi(WO4 )2 -Bi2 WO6 heterostructure, which was designed and synthesized by using a simple hydrothermal method. Methyl orange was used as a representative dye indicator to evaluate the visible-light catalytic activity and the catalytic mechanism was investigated. The as-synthesized AgBi(WO4 )2 -Bi2 WO6 composite displayed a 43 times higher photocatalytic activity than Bi2 WO6 . Owing to the matched band gap and distinctive heterostructure, AgBi(WO4 )2 -Bi2 WO6 reveals a high visible-light response and high-efficiency utilization of both photogenerated electrons and holes. AgBi(WO4 )2 reveals a similar energy level to and good lattice match with Bi2 WO6 , which are favorable qualities for band bending and fluent electron transfer. Furthermore, the photoexcited electrons can produce oxygen to generate (.) O2 (-) radicals, which is vital for the overall utilization of both holes and electrons. This is the first example of AgBi(WO4 )2 being used as photocatalytic material.

The alkaline phosphatase (ALP) biocatalysis followed by the in situ enzymatic generation of a visible light responsive nanozyme is coupled to elucidate a novel amplification strategy by enzymatic cascade reaction for versatile biosensing. The enzymatic hydrolysis of o-phosphonoxyphenol (OPP) to catechol (CA) by ALP is allowed to coordinate on the surface of TiO2 nanoparticles (NPs) due to the specificity and high affinity of enediol ligands to Ti(IV). Upon the stimuli by CA generated from ALP, the inert TiO2 NPs is activated, which demonstrates highly efficient oxidase mimicking activity for catalyzing the oxidation of the typical substrate of 3,3',5,5'-tetramethylbenzidine (TMB) under visible light (λ ≥ 400 nm) irradiation utilizing dissolved oxygen as an electron acceptor. On the basis of the cascade reaction of ALP and the nanozyme of CA coordinated TiO2 (TiO2-CA) NPs, we design exquisitely colorimetric biosensors for probing ALP activity and its inhibitor of 2, 4-dichlorophenoxyacetic acid (2,4-DA). Quantitative probing of ALP activity in a wide linear range from 0.01 to 150 U/L with the detection limit of 0.002 U/L is realized, which endows the methodology with sufficiently high sensitivity for potentially practical applications in real samples of human serum (ALP level of 40-190 U/L for adults). In addition, a novel immunoassay protocol by taking mouse IgG as an example is validated using the ALP/nanozyme cascade amplification reaction as the signal transducer. A low detection limit of 2.0 pg/mL is attained for mouse IgG, which is 4500-fold lower than that of the standard enzyme-linked immuno-sorbent assay (ELISA) kit. Although only mouse IgG is used as a proof-of-concept in our experiment, we believe that this approach is generalizable to be readily extended to other ELISA systems. This methodology opens a new horizon for amplified and versatile biosensing including probing ALP activity and following ALP-based ELISA immunoassays.

In this work, we report a novel AgBi(WO4 )2 -Bi2 WO6 heterostructure, which was designed and synthesized by using a simple hydrothermal method. Methyl orange was used as a representative dye indicator to evaluate the visible-light catalytic activity and the catalytic mechanism was investigated. The as-synthesized AgBi(WO4 )2 -Bi2 WO6 composite displayed a 43 times higher photocatalytic activity than Bi2 WO6 . Owing to the matched band gap and distinctive heterostructure, AgBi(WO4 )2 -Bi2 WO6 reveals a high visible-light response and high-efficiency utilization of both photogenerated electrons and holes. AgBi(WO4 )2 reveals a similar energy level to and good lattice match with Bi2 WO6 , which are favorable qualities for band bending and fluent electron transfer. Furthermore, the photoexcited electrons can produce oxygen to generate (.) O2 (-) radicals, which is vital for the overall utilization of both holes and electrons. This is the first example of AgBi(WO4 )2 being used as photocatalytic material.

A novel CdSe/NiO heteroarchitecture was designed, prepared, and used as a photocathode for hydrogen generation from water. The composite films were structurally, optically, and photoelectrochemically characterized. The deposition of CdSe on the NiO film enhanced light harvesting in the visible-light region and photoelectrochemical properties. Moreover, the CdSe/NiO photoelectrode showed superior stability both in nitrogen-saturated and air-saturated neutral environments. The CdSe/NiO photoelectrode after MoS2 modification retained the stability of the CdSe/NiO electrode and exhibited higher photocatalytic and photoelectrochemical performances than the unmodified CdSe/NiO electrode. In pH 6 buffer solution, an average hydrogen-evolution rate of 0.52 μmol h(-1) cm(-2) at -0.131 V (versus reversible hydrogen electrode, RHE) was achieved on a MoS2 /CdSe/NiO photocathode, with almost 100 % faradaic efficiency.

In this report, a novel nanocomposite of highly dispersed CeO2 on a TiO2 nanotube was designed and proposed as a peroxidase-like mimic. The best peroxidase-like activity was obtained for the CeO2/nanotube-TiO2 when the molar ratio of Ce/Ti was 0.1, which was much higher than that for CeO2/nanowire-TiO2, CeO2/nanorod-TiO2, or CeO2/nanoparticle-TiO2 with a similar molar ratio of Ce/Ti. Moreover, in comparison with other nanomaterial based peroxidase mimics, CeO2/nanotube-TiO2 nanocomposites exhibited higher affinity to H2O2 and 3,3',5,5'-tetramethylbenzidine (TMB). Kinetic analysis indicated that the catalytic behavior was in accordance with typical Michaelis-Menten kinetics. Ce(3+) sites were confirmed as the catalytic active sites for the catalytic reaction. The first interaction of surface CeO2 with H2O2 chemically changed the surface state of CeO2 by transforming Ce(3+) sites into surface peroxide species causing adsorbed TMB oxidation. Compared with CeO2/nanowire-TiO2, CeO2/nanorod-TiO2, and CeO2/nanoparticle-TiO2, the combination of TiO2 nanotube with CeO2 presented the highest concentration of Ce(3+) thus leading to the best peroxidase-like activity. On the basis of the high activity of CeO2/nanotube-TiO2, the reaction provides a simple method for colorimetric detection of H2O2 and glucose with the detection limits of 3.2 and 6.1 μM, respectively.

of air at 140°C. Through the study of thermal analysis of fiber feedthrough, we got the temperature field distribution and heat flux distribution of the optical feedthrough. Optical feedthrough will produce thermal stress when it is heated. And the thermal stress will affect the performance of optical feedthrough. Consider this real problem, we carried out the thermal-structural analysis further. Then we simulated the thermal deformation in the process of optical feedthrough heating, got the stress field and deformation of optical feedthrough. And we also analyzed whether structural damage will happen when the fiber feedthrough working on the specific temperature. This study provide a basis for the same type structure.

The fluorogenic property of guaiacol was exploited for the first time to analyze the interaction with target protein as a probe by molecular modeling, fluorescence, circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy. Molecular docking was performed to reveal the possible binding mode or mechanism and suggested that guaiacol can strongly bind to human immunoglobulin (HIgG). It is considered that guaiacol binds to HIgG mainly by a hydrophobic interaction and there are two hydrogen bond interactions between the drug and the residues LEU 80 and ASP 65, which is in good agreement with the results from the experimental thermodynamic parameters (the enthalpy change Δ H 0 and the entropy change Δ S 0 were calculated to be 65.55 kJ·mol -1 and 132.95 J·mol -1 ·K -1 according to the Vant’ Hoff equation). Data obtained by the fluorescence spectroscopy indicated that binding of guaiacol with HIgG leads to dramatic enhancement in the fluorescence emission intensity along with significant occurrence of efficient Forster resonance energy transfer (FRET) from the residue of HIgG to the protein bound guaiacol. From the low value of fluorescence anisotropy ( r = 0.06), it is argued that the probe molecule is located in the motionally unrestricted environment of the protein. The alterations of protein’s secondary structure in the presence of guaiacol in aqueous solution were quantitatively calculated by the evidences from FT-IR and CD spectroscopes.

A method of nonaqueous capillary electrophoresis was established for the separation and determination of alanine, phenylalanine, isoleucine and valine after derivatization with 4-chloro-7-nitrobenzo-2-oxa-1, 3-diazol in nonaqueous media. The derivatization and separation conditions were optimized. The optimum derivatization conditions were 70 min for the reaction time, 55 °C for the reaction temperature and 20 mM ammonium acetate in methanol for the derivatization buffer. The most suitable running buffer was composed of 60 mM ammonium acetate, 10% acetonitrile in methanol with a fused-silica capillary column (47 cm × 75 µm i.d.), 20 kV applied voltage and 20 °C capillary temperature. The correlation coefficients were better than 0.995 in the investigated concentration ranges. The relative standard deviation (R.S.D.) (n = 5) of the migration times and peak areas were 2.0–4.3% and 1.9–4.5%, respectively. The method was applied to the determination of four compounds in two compound amino acid injections, with the exception of phenylalanine, the recoveries for the other three compounds ranging between 88–116%.

A nonaqueous capillary electrophoresis with laser-induced fluorescence detection method was developed for the quantification of ephedrine and pseudoephedrine after derivatization with 4-chloro-7-nitrobenzo-2-oxa-1, 3-diazol in nonaqueous media. The derivatization was made in off-line mode. By a series of optimizations, a derivatization buffer composed of 40 mm ammonium acetate and 20% acetonitrile and a running buffer composed of 80 mm ammonium acetate and 3% acetic acid were applied for the derivatization and separation of ephedrine and pseudoephedrine, respectively. Linear relationships for ephedrine and pseudoephedrine were obtained in the range 1.23-19.60 mg/L (correlation coefficients 0.9970 for ephedrine and 0.9994 for pseudoephedrine), and the detection limits for ephedrine and pseudoephedrine were 0.014 and 0.011 mg/L, respectively. The method was applied to the analysis of ephedrine and pseudoephedrine in four preparations with recoveries in the range 93.9-105.1%.

A novel poly(acryl-benzoylamidrazone-acryl-benzoylhydrazine) chelating fiber was synthesized simply from nitrilon (polyacrylonitrile fiber). The structure of the chelating fiber was verified with the help of FT-IR spectrum. The parameters influencing the efficiency of the fiber for concentrating trace amounts of Au(III) and Pd(IV) were investigated in detail. Trace Au(III) and Pd(IV) were enriched and separated from real sample solutions and detected using inductively coupled plasma atomic emission spectrometry (ICP-AES) with satisfactory results. The experiments show that the method is rapid, precise, simple and convenient to use.

A novel poly(acryl-p-toluenesulfonamideamidine-p-toluenesulfonylamide) chelating fiber containing S, N and O elements was synthesized from polyacrylonitrile fiber and p-toluenesulfonamide and used for the preconcentration and separation for traces of Ru(III), Rh(III), Au(III) and Pd(IV) ions from waste water and ore sample solution. The synthesis of this fiber was simple and rapid. The results indicate that 100 ng mL−1 of these ions can be quantitatively enriched by the chelating fiber at a flow rate of 6 mL min−1 and a pH of 4 and desorbed quantitatively with 20 mL of 6 mol L−1 HCl and 5% CS(NH2)2 solution at 50 °C (with recovery> 95%). A 50 to 1000-fold excess of Ca2+, Mg2+, Mn2+, Co2+, Fe3+, Cu2+, Zn2+, and Al3+ ions caused little interference in the concentration and determination of the analyzed ions. When the fiber had been reused twenty times, the recoveries of the ions enriched by the fiber were still over 96%. The saturated adsorption capacities of the fiber were in the range of 22–96 mg g−1. The relative standard deviation (RSD) of the method was between 0.70% and 0.84%. Recoveries of a standard added to actual samples were in range of 95–101%. The results obtained for these ions in real solution samples were basically in agreement with the given values, the average errors being below 5.0%. FT-IR spectra show that the existence of –SO2–Ar, HN=C–NH–, O=C–NH– and –NH–SO2 functional groups are verified in the chelating fiber. The experiments show that the method is rapid, precise, simple and convenient.

A novel mesoporous MoO2 composite supported on graphene oxide (m-MoO2/GO) has been designed and applied as an efficient epoxidation catalyst. The m-MoO2/GO composite was characterised by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, Brunauer–Emmet–Teller surface area analysis, field emission scanning electron microscopy, and transmission electron microscopy. Compared with pure mesoporous MoO2 (m-MoO2) and amorphous MoO2-graphene oxide (a-MoO2/GO), m-MoO2/GO exhibits the best catalytic activity. The conversion and selectivity for cyclooctene are both over 99 % in 6 h. Remarkably, the mesoporous structure in m-MoO2/GO which derives from SiO2 nanospheres endows the catalyst better catalytic performance for long chain olefins: the conversion of methyl oleate can be as high as 82 %. Such a robust catalyst can be easily recycled and reused five times without significant loss of catalytic activity. This novel catalyst is promising in the synthesis of epoxides with a long carbon chain or large ring size.

Photocathode based on p-type PbS quantum dots (QDs) combing a novel signal amplification strategy utilizing catalase (CAT) mimetics was designed and utilized for sensitive photoelectrochemical (PEC) detection of DNA. The bio-bar-coded Pt nanoparticles (NPs)/G-quadruplex/hemin exhibited high CAT-like activity following the Michaelis–Menten model for decomposing H2O2 to water and oxygen, whose activity even slightly exceeded that of natural CAT. The bio-bar-code as a catalytic label was conjugated onto the surface of PbS QDs modified electrodes through the formed sandwich-type structure due to DNA hybridization. Oxygen in situ generated by the CAT mimetics of the bio-bar-code of Pt NPs/G-quadruplex/hemin acted as an efficient electron acceptor of illuminated PbS QDs, promoting charge separation and enhancing cathodic photocurrent. Under optimal conditions, the developed PEC biosensor for target DNA exhibited a dynamic range of 0.2 pmol/L to 1.0 nmol/L with a low detection limit of 0.08 pmol/L. The high sensitivity of the method was resulted from the sensitive response of PbS QDs to oxygen and the highly efficient CAT-like catalytic activity of the bio-bar-coded Pt NPs/G-quadruplex/hemin.

An ultrasensitive photoelectrochemical (PEC) immunoassay based on signal amplification by enzyme mimetics was fabricated for the detection of mouse IgG (as a model protein). The PEC immunosensor was constructed by a layer-by-layer assembly of poly (diallyldimethylammonium chloride) (PDDA), CdS quantum dots (QDs), primary antibody (Ab1, polyclonal goat antimouse IgG), and the antigen (Ag, mouse IgG) on an indium-tin oxide (ITO) electrode. Then, the secondary antibody (Ab2, polyclonal goat antimouse IgG) combined to a bio-bar-coded Pt nanoparticle(NP)-G-quadruplex/hemin probe was used for signal amplification. The bio-bar-coded Pt NP-G-quadruplex/hemin probe could catalyze the oxidation of hydroquinone (HQ) using H2O2 as an oxidant, demonstrating its intrinsic enzyme-like activity. High sensitivity for the target Ag was achieved by using the bio-bar-coded probe as signal amplifier due to its high catalytic activity, a competitive nonproductive absorption of hemin and the steric hindrance caused by the polymeric oxidation products of HQ. For most important, the oxidation product of HQ acted as an efficient electron acceptor of the illuminated CdS QDs. The target Ag could be detected from 0.01pg/mL to 1.0ng/mL with a low detection limit of 6.0fg/mL. The as-obtained immunosensor exhibited high sensitivity, good stability and acceptable reproducibility. This method might be attractive for clinical and biomedical applications.

Due to the intrinsic hole oxidation reaction occurred on the photoanode surface, currently developed photoelectrochemical biosensors suffer from the interference from coexisting reductive species (acting as electron donor) and a novel design strategy of photoelectrode for photoelectrochemical detection is urgently required. In this paper, a self-operating photocathode based on CdS quantum dots sensitized three-dimensional (3D) nanoporous NiO was designed and created, which showed highly selective and reversible response to dissolved oxygen (acting as electron acceptor) in the electrolyte solution. Using glucose oxidase (GOD) as a biocatalyst, a novel photoelectrochemical sensor for glucose was developed. The commonly encountered interferents such as H2O2, ascorbic acid (AA), cysteine (Cys), dopamine (DA), etc., almost had no effect for the cathodic photocurrent of the 3D NiO/CdS electrode, though these substances were proved to greatly influence the photocurrent of photoanodes, which indicated greatly improved selectivity of the method. The method was applied to detect glucose in real samples including serum and glucose injections with satisfactory results. This study could provide a new train of thought on designing of self-operating photocathode in photoelectrochemical sensing, promoting the application of semiconductor nanomaterials in photoelectrochemistry.

A high-performance liquid chromatographic method using a single standard has been established for the quantitative analysis of four podophyllum lignans in Dysosma versipellis (Hance) M. Cheng and Podophyllum emodi Wall. Var. chinesis Sprague. The method involved the quantitative analysis of multiple components by a single marker. The chromatographic method was validated for linearity and range, limit of detection and qualification, precision, stability, reproducibility and robustness. Relative correcting factors were calculated and examined by five concentrations of four podophyllum lignans, two high-performance liquid chromatographic systems and three chromatographic columns. The method was applied to analyze 10 batches of samples. The quantitative results were compared with the results by an external standard method through intra-class coefficient, which indicated that the established method was reliable for the determination of the four podophyllum lignans in the two medicinal plants.

A novel colorimetric thiourea (TU) sensor was developed utilizing citrate modified silver nanoparticles (AgNPs). The introduction of TU reduced the overall surface charges of the AgNPs, resulting in aggregation of AgNPs and a colorimetric response correlating with the concentration of TU. The detection of TU could be realized within 2 min, with an ultralow detection limit of 0.8 nM by the absorption method. In addition, the AgNPs sensor also showed good selectivity in the presence of potential interfering compounds. Since common steps such as modification and separation could be successfully avoided, the sensor developed here could provide a simple, cost-effective yet rapid and sensitive measurement tool for TU detection, and may provide new opportunities in the development of sensors for food safety and environmental monitoring in the future.

The method provides an innovative dual functional sensors for mercury (II) ions and hydrogen peroxide. The addition of H(2)O(2) to the mixture of silver nanoparticles (AgNPs) and Hg(2+) induced color changes of the solution within several seconds even at 2.0 nM Hg(2+). Other metallic ions could not induce color change even at 10 μM. Of importance, this probe was not only successfully applied to detect Hg(2+), but also it could be used to sense H(2)O(2) at a concentration as low as 50 nM (by naked-eye). The outstanding sensitivity and selectivity property for Hg(2+) and H(2)O(2) resulted from the AgNPs mediated reduction of Hg(2+) to elementary Hg in the presence of H(2)O(2), causing the aggregation and colorimetric response of AgNPs. This sensitive and selective colorimetric assay opens up a fresh insight of development facile and fast detection methods for metal ions and biomolecules using the special catalytic reactivity of AgNPs.

The scrap tire crumb rubber modified (CRM) bitumen mixture with over 20% crumb has higher viscosity, better flexibility, improved anti-fatigue and anti-aging properties. This paper mainly investigated material design and performance of asphalt rubber stone mastic mix (AR-SMA). The rotation viscosity test was used to ascertain adoption of fiber in AR-SMA. Due to the swelling of asphalt rubber mortar, the gap-coarse graded aggregate must be used in asphalt rubber concrete to provide enough free space. This paper reinforces material composition and grade proportion range of adapted AR-SMA depending on special characteristic of this mix. After confirming best grade of AR-SMA, this paper used the Marshall method to design job mix formula (JMF) of AR-SMA13. The best CRM asphalt binder content and feasible gradation middle value were obtained by Marshall Test and volume parameter calculation. In performance evaluation phase, two SMA usually used in Beijing region were added in comparison with AR-SMA. Mechanical properties of AR-SMA mix were evaluated by wheel rutting test(WRT), midpoint beam bending test (MBBT) at low temperatures, indirect tensile strength test(ITST) at various freeze/thaw cycles, Cantabro test, and Schellenburg binder drainage test. The results indicate that the pavement performance of AR-SMA is very excellent, compared to the other two SMA's frequently used in Beijing region.

The importance of cysteine (Cys) in biological systems has stimulated a great deal of efforts in the development of analytical methods for the determination of this amino acid. In this work, a novel fluorescent probe for Cys based on citrate (Cit)-capped CdS quantum dots (QDs) is reported. The Cit-capped CdS QDs fluorescent probe offers good sensitivity and selectivity for detecting Cys. A good linear relationship was obtained from 1.0 × 10 −8 mol L −1 to 5.0 × 10 −5 mol L −1 for Cys. The detection limit was calculated as 5.4 × 10 −9 mol L −1 . The proposed method was applied to detect Cys in human urine samples, which showed satisfactory results. This assay is based on both the lability of Cit and the strong affinity of thiols to the surface of CdS QDs. The addition of Cys improved the passivation of the surface traps of CdS QDs and enhanced the fluorescence intensity.

Using FeSO4 x 7H2O and H2O2 as raw materials, a facile route to selective synthesis of alpha-FeOOH and alpha-Fe2O3 nanorods was developed by adjusting the reaction temperature in hydrothermal synthesis. Without undergoing calcinations, the obtained alpha-FeOOH nanorods (at 150 degrees C) and alpha-Fe2O3 nanorods (at 200 degrees C) possess high morphological yield (> 95%). The influences of synthesis conditions such as H2O2, hydrothermal temperature and hydrothermal time were investigated. The formation process of alpha-FeOOH and alpha-Fe2O3 nanorods was discussed in detail, and a possible temperature-controlled selective synthesis mechanism was proposed.