The aim of this work was to develop an alginate-casein composite microsphere as a bioactive vehicle for oral administration of nutrients by a simple extrusion dripping method. Riboflavin was selected as a model drug, and the microencapsulation efficiency was raised to 97.94% after optimizing the preparation conditions by response surface methodology. In vitro release studies showed that riboflavin was released completely from alginate-casein microspheres in simulated intestinal fluids. Meanwhile, the morphology, structure and interaction between alginate and casein were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectra.

Liquid-liquid equilibrium data of two ternary systems methyl palmitate+ethanol+glycerol and methyl stearate+ethanol+glycerol at(318.2 and 333.2)K and atmospheric pressure were measured. The values of distribution coefficient and selectivity were calculated, which indicates that glycerol can be separated from fatty acid ester by using ethanol as an extraction solvent. The consistency of the isothermal tie-line data were checked by the Othmer-Tobias equation. The correlation coefficients R ₂ are higher than 0.993,9 for all the fitted curves. The NRTL activity coefficient model was applied to the correlation of the measured tie-line data. The root mean square deviation(RMSD)values are less than 0.007 for all the systems, which shows a good predictive capability of this model for such systems.

A series of metal chlorides supported solid catalysts were prepared by simple wet impregnation method. Their catalytic performances for Friedel-Crafts acylation of toluene with benzoyl chloride were evaluated and the excellent results were obtained over FeCl₃/SiO₂. These catalysts were characterized by BET, NH₃-TPD and FT-IR of pyridine adsorption to clarify the structure-activity relationship. It was found that FeCl₃/SiO₂ has larger pore size and pore volume than other catalysts, which increased the accessibility of the catalyst. In addition, FeCl₃/SiO₂ exhibited higher molar ratio of Lewis acid sites and Brφnsted acid sites, which might be another reason for the increase of toluene conversion. Furthermore, the reaction parameters, including temperature, time and molar ratio, were optimized. Under the optimized conditions, 91.2%, conversion and 82.0%, selectivity were obtained. Meanwhile, the generality of the catalyst was demonstrated by the acylations of alkyl substituted aromatics. Finally, the catalyst was reused for four runs with slight loss in catalytic activity, which attributed to the drain of the active component.

A series of 4,4’-disubstituted-[2,2’]-bipyridines, featuring electron withdrawing/donating functional groups such as amino, chloro, nitro, ethoxycarbonyl, carboxy, methyl, methoxy and hydroxymethyl, have been synthesized and employed in the copolymerization of carbon monoxide(CO)and styrene. The available bipyridine and its derivatives were coordinated with palladium(II)acetate for catalyzing the copolymerization of CO and styrene, and the concomitant polyketone was characterized by means of ¹³C NMR, FTIR, differential scanning calorimetry( DSC)and element analysis techniques concerning its structure and thermal performance. The effect of different electron-donating and electron-withdrawing groups on catalyst performance and molecular weight of copolymer was studied under certain experimental condition. It has been proved that the enhancement of electron donating and conjugative effects on bipyridine ligand will not only improve the catalytic activity of the composition, but also increase the molecular weight of the as-prepared polyketone. The catalytic activity is the highest in hydroxymethyl substituted 2,2’-bipyridine ligand(1 356 gSTCO/(gPd · h)), when the molecular weight and polydispersity index of the polyketone are M _n=8 502,M _w=1 3440 and M _w/M _n=1.581, respectively.

A fast and facile method of fabricating fiber-optic localized surface plasmon resonance sensors based on spherical gold nanoparticles was introduced in this study. The gold nanoparticles with an average diameter of 55 nm were synthesized via the Turkevich method and were then immobilized onto the surface of an uncladded sensor probe using a polydopamine layer. To obtain a sensor probe with high sensitivity to changes in the refractive index, a set of key optimization parameters, including the sensing length, coating time of the polydopamine layer, and coating time of the gold nanoparticles, were investigated. The sensitivity of the optimized sensor probe was 522.80 nm per refractive index unit, and the probe showed distinctive wavelength shifts when the refractive index was changed from 1.328 6 to 1.398,7. When stored in deionized water at 4 °C, the sensor probe proved to be stable over a period of two weeks. The sensor also exhibited advantages, such as low cost, fast fabrication, and simple optical setup, which indicated its potential application in remote sensing and real-time detection.

Polystyrene(PS)@SiO₂ core-shell microbeads with large pore and large particle size were prepared via layer-by-layer(LBL)assembly technique for potential applications in nano-micro composites. Negative silica nanoparticles synthesized via modified Stöber method and cationic poly(diallyldimethylammonium chloride)were alternately adsorbed on the surface of microbeads. Zeta potential, size, and morphology of the microbeads were monitored during LBL assembly process to ensure the successful deposition of silica nanoparticles. The porous shell was characterized using nitrogen adsorption and desorption analyses, and the surface area, volume and diameter of the pores were derived. It is found that the porous shell thickness and the pore size can be tuned by changing the coating times of silica nanoparticles. Finally, PS@SiO₂ core-shell microbeads with 5,μm PS solid core and 350,nm mesoporous shell(mean BJH pore diameter is ~27,nm)were used to load CdSe/ZnS quantum dots(QDs). The fluorescence microscopic image and the optical amplification of the QDs-embedded microbeads (QDBs)indicate that the as-prepared core-shell microbeads can provide adequate space for QDs and may be useful for further application of nano-micro composites.

Ethanol-water near-azeotropic mixture dehydration was investigated by formulated compound starchbased adsorbent(CSA), which consists of corn, sweet potato and foaming agent. The net retention time and separation factor of water over ethanol were measured by inverse gas chromatography(IGC). Results indicated that water has a longer net retention time than ethanol and that low temperature is beneficial to this dehydration process. Orthogonal test was conducted under different vapor feed flow rates, bed temperatures and bed heights, to obtain optimal fixed-bed dehydration condition. Dynamic saturated adsorbance was also studied. It was found that CSA has the same water adsorption capacity(0.15 g/g)as some commercial molecular sieves. Besides, this biosorptive dehydration process was found to be the most energy-efficient compared with other ethanol purification processes.

Antioxidant peptides of flatfish skin protein hydrolyzed by four enzymes(Papain, Pepsin, Trypsin and Neutrase, respectively)were investigated. The Trypsin hydrolysate obtained by hydrolysis exhibited the highest 1,1-dipheny-l-2-picrylhydrazyl(DPPH)radical scavenging activity(DRSA)compared with other hydrolysates. Response surface method ology(RSM), based on Box-Behnken design, was used to study the influence of hydrolysis conditions on the DRSA. The optimal hydrolysis conditions were as follows: pH 7.38, temperature 48.2°C and enzyme/substrate(E/S)ratio 2 840 U/g. Under these conditions, the maximum DRSA was(22.85 ± 0.57)%,. The experimental values agreed with the value (23.09%,)predicted by the model within a 95%, confidence interval. By using gel filtration chromatography and reversed-phase high performance liquid chromatography(RP-HPLC), antioxidant peptide(D2-P)was isolated from flatfish skin protein hydrolysates(FSPH)and could exhibit a(54.28 ± 1.37)%, scavenging activity on DPPH radical at the concentration of 5 mg/mL. This is the first report of a scientific basis for the preparation of antioxidant peptides from flatfish skin. The results suggested that the antioxidant peptides can be exploited into functional foods or used as a novel source of nutraceuticals.

In order to investigate the effect of plant density of Potamogeton crispus L. on the remediation of sediments contaminated by polycyclic aromatic hydrocarbons, a 54-day experiment with four plant densities(642, 1,604, 2,567 and 3,530 plants/m²)was conducted. The results showed higher plant density with slower plant growth rate. Surface area per plant was the most sensitive root parameter to plant density. At the end of the 54-day experiment, planting P. crispus enhanced the dissipation ratios of phenanthrene and pyrene in sediments by 6.5%—26.2% and 0.95%—13.6%, respectively. The dissipation increment increased with increasing plant density. Plant uptake accounted for only a small portion of the dissipation increments. Furthermore, P. crispus could evidently improve sediment redox potentials, and strong positive correlations between root surface area and the redox potential as well as between the redox potentials and the dissipation ratios of phenanthrene and pyrene were obtained, indicating that the oxygen released by the roots of P. crispus might be the main mechanism by which P. crispus enhanced the dissipation of PAHs in sediments.

In this paper, a 2-D airlift reactor was developed. The streamline and hydrodynamic parameters were measured in a 2-D airlift loop reactor(ALR)with different draft baffles. Three regimes were observed under different conditions. Particle image velocimetry(PIV)measurement showed that the liquid velocity distribution in horizontal direction presented different profiles in the three regimes. The length, the height and the spacing of draft baffles were applied in the experiments to optimize the ALR structure. It was found that the draft tube structure is of great importance in determining the hydrodynamics of ALRs. Additionally, the experimental results may serve as a step to the further optimization and design of ALR.

The accelerated life test was carried out to investigate the change of spectral transmittance of di-methyl silicon oil and the effects on the electrical performance of silicon solar cell. The di-methyl silicon oil samples before and after accelerated life test were analyzed by FT-IR, GC-MS and LC-MS. The ring compounds and linear compounds with larger molecular weight were detected. The spectral transmittance of di-methyl silicon oil decreased because the chromophore and auxochrome of the products made a sunlight receive decrease on the surface of the solar cell, and resulted in the reduction of cell performance. According to the decrease of spectral transmittance of di-methyl silicon oil, two recovery methods were proposed. The results showed that extraction was superior to vacuum distillation in recovering the aged di-methyl silicon oil.

Reverse transcription quantitative PCR(RT-qPCR)combined with the published genome information of Saccharopolyspora spinosa can allow sophisticated studies about S. spinosa, including studying the regulation of spinosyn biosynthesis, finding new target genes for engineering, and discovering and exploiting other macrolide secondary metabolites. Studies have demonstrated that appropriate internal control is needed to normalize target genes at transcription levels. However, many studies have shown that no single reference gene is universal for all strains under all experimental conditions. Thus, eight candidate reference genes of three different S. spinosa strains in two different cultures were studied to find suitable reference gene(s). The number of amplification cycles of these candidate genes was calculated by BestKeeper, NormFinder and geNorm. The results indicated that the most suitable reference genes for normalization during the fermentation of S. spinosa were 16S rRNA and rbL13.

Carotenoid isomerase(CRTISO)is a key enzyme that catalyzes the conversion of cis-lycopene to alltrans lycopene. In this study, we isolated and characterized the CRTISO gene from Lycium chinense (LcCRTISO) for the first time. The open reading frame of LcCRTISO was 1 815 bp encoding a protein of 604 amino acids with a molecular mass of 66.24 kDa. Amino acid sequence analysis revealed that the LcCRTISO had a high level of similarity to other CRTISO. Phylogenetic analysis displayed that LcCRTISO kept a closer relationship with the CRTISO of plants than with those of other species. Semi-quantitative PCR analysis indicated that LcCRTISO gene was expressed in all tissues tested with the highest expression in maturing fruits. The overexpression of LcCRTISO gene in transgenic tobacco resulted in an increase of total carotenoids in the leaves with β-carotene and lutein being the predominants. The results obtained here clearly suggested that the LcCRTISO gene was a promising candidate for carotenoid production.