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pH- and temperature-sensitive nanogels (NGs) were prepared from sodium alginate (SA) and N-isopropylacrylamide (NIPAM), as the sensitivity at pH 5.5 and 31 °C. SA was pH-modified with glutamic acid (Glu) and ethylenediamine (EDA). The products Glu-SA (Glu-modified SA) and EGSA (EDA- and Glu-modified SA) were characterized by ninhydrin color reaction, infrared spectroscopy, and zeta potential, and the best reactant ratio was selected. Moreover, temperature-sensitive, pH-sensitive EGSA-NGs possessing a semi-interpenetrating network structure were prepared by radical polymerization using N-isopropylacrylamide. The morphology of EGSA-NGs was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The cytotoxicity test shows the low cytotoxicity and high biocompatibility of the NGs. The newly prepared NGs were also subjected to pH-sensitive temperature-sensitive in vitro drug-loading and drug-release experiments. The pH-sensitive and temperature-sensitive experiments showed that the particle size of EGSA-NGs was reduced at pH 5.5 and above 31 °C. The drug-loading and drug-release experiments also confirmed this finding, indicating that the newly synthesized NGs could release the drug according to the environmental changes. Therefore, the material has potential application value in solid tumor targeted therapy.

The purpose of our research is to find a new nanoparticle to conjugate BSA with a low water-soluble antitumor compound, cinnamaldehyde (CA). In this study, a cinnamaldehyde derivative (CAH) was synthesized by reacting CA with anthraniloyl hydrazine (AH) to obtain a pharmaceutical carrier with medicinal activity, and the yield can be 95%. BSA–CAH nanoparticles (NPs) were prepared by a desolvation method. Following modification, the isoelectric point of the NPs increased to 5.5–6.0, with negative changes in tumor micro environment. The microscopy analyses revealed that the NPs were homogeneously dispersed and exhibited a circular-granular structure, with 172 nm size. The modified BSA was characterized for the structure by various spectral analysis. The results showed that the content of β-turns and the antiparallel β-sheet increased, the fluorescence intensity at 370 nm was also significantly enhanced and red-shifted, so that the degree of conjugation increased after modification. Gel permeation chromatography (GPC) revealed that the molecular weight of the NPs was 83.629 kDa, confirming that 56 CAH molecules were conjugated to one molecule of BSA. By stability analysis, in solution, the NPs were stable for 30 days at room temperature, comparing with free CA. Moreover, the cell uptake experiment revealed that BSA–CAH NPs entered cancer cells as carriers and inhibited the majority of the studied cancer cell lines by FITC label. Notably, the laryngeal cancer inhibition rate was >80%. BSA–CAH NPs prepared herein exhibited promising anticancer activity.

Anion exchange membranes (AEMs) with a high ion exchange capacity, striking water uptake and excellent dimensional stability were prepared via an internal crosslinking networks strategy. Internal crosslinking networks were formed by reacting 4,4′-bipyridine with brominated poly (2,6-dimethyl-1,4-phenylene oxide) (BPPO). 4,4′-bipyridine not only provides a functional group but also comprises a cross-linking agent without requirements of post-functionalization. The variation of the 4,4′-bipyridine amount into the casting polymer solution was explored to regulate the performance of the anion exchange membranes, and the membrane properties were evaluated by AFM, ion exchange capacity (IEC), water uptake, the linear expansion ratio, tensile strength, thermal stability, membrane area resistance and electrodialysis experiments, etc. The results showed that the cross-linked membrane with the IEC of 1.98 mmol/g has much more outstanding dimensional stability (water uptake: 11.68%; swelling ratio: 3.8%) than non-cross-linked BPPO-Tri membrane (water uptake: 53.26%; swelling ratio: 7.71%) and commercial Neosepta AMX membrane (water uptake: 60.29%; swelling ratio: 5.08%), at the high temperature (50 °C). When being applied in ED application, the cross-linked BPPO-20 membrane (NaCl remove: 59.7%; energy consumption: 5.97 kWh/kg NaCl) exhibits slightly higher desalination efficiency and lower energy consumption than commercial Neosepta AMX membrane (NaCl remove: 58.3%; energy consumption: 6.51 kWh/kg NaCl), suggesting its promising application in ED.

Matrix factorization is an effective solution to sparse data problem in the recommendation algorithm, but it relies too much on the user's direct behavior, preventing the algorithm from representing the user's true preference for an item. In order to address this challenge, this paper establishes an implicit feedback model through the movie view duration based on explicit feedback. The alternating least-squares method and its optimization method ALS-WR are introduced to factorize the explicit feedback model and the implicit feedback model respectively into two user-latent factor matrices and two item-latent factor matrices. Then the concept of weight-value is introduced to integrate each pair of user-latent factor matrices and item-latent factor matrices to finally produce recommendations. The simulation experiment on the MovieLens dataset is compared with the ALS-based, ALS-WR-based, and SVD-based recommendation algorithms. The experiment results show that the algorithm proposed in the paper is superior to the above algorithms in terms of mean absolute error (MAE) and root mean square error (RMSE), and is effective in improving the quality of recommendation.

Silicon oxycarbide (Si–O–C) materials with high specific capacity are considered as a promising anodic material alternative to commercial graphite for advanced Li-ion batteries. However, the rapid capacity fading and poor rate performance are the main obstacles for practical application and still remain a large challenge. In this work, microalgae (Nannochloropsis) served as a biological template and carbon source to synthesize Si–O–C microspheres with the assistance of supercritical CO2 fluid. Compared to conventional artificial templates, microalgae is abundant, renewable and available, and can be regarded as a promising biological template. Meanwhile, supercritical CO2 fluid with high penetration, high diffusivity and high dissolving capacity can serve as a superior solvent to guarantee the efficient mass transfer and uniform dispersion of precursors. As anodic materials for Li-ion batteries, Si–O–C microspheres exhibit a high reversible specific capacity of 450 mA h g−1 at a current density of 0.1 A g−1 over 200 cycles, excellent rate cycling stability and high coulombic efficiency (100%). The discovery of this novel strategy to fabricate Si–O–C materials presents possibilities for energy storage applications.

Reliable and repeatable insect thermal mortality data rely on the performance of a heating device. Computer simulation has been widely used to optimize structures, design parameters and process conditions. To improve the temperature uniformity of a heating block system (HBS), a computer model was developed using finite element software COMSOL. Good agreement was obtained between the simulated and experimental block surface temperatures at three positions of the HBS and three heating rates. The validated computer model was further used to predict the effects of heating rates, the position of test insects and the addition of gases on the block and air temperature distributions. Simulation results showed that increasing heating rate reduced heating uniformity. The position of test insects in the treatment chamber largely affected their heating rate, with a position closer to the surface of the heat block providing a better temperature match between test insects and the HBS. When gas was added, block temperatures within the treatment chamber, particularly near the gas inlet, were influenced by gas speeds, temperatures and the gas channel design. The heating uniformity in the treatment chamber of the HBS was improved by heating the gas before adding it to the HBS, by routing the gas channel through the heating block to preheat the gas, and by using a relatively slow gas speed. The simulation results demonstrated that the validated computer model could be a reliable tool to evaluate the heating performance of the HBS for studying insect thermal death kinetics and optimize treatment conditions for the HBS when modified to include controlled atmospheres.

Radio frequency (RF) heating is considered as a potential postharvest technology for disinfesting legumes. However, the non-uniformity in RF heating is still a major problem in developing effective RF heat treatments for pest control and other applications. A computer simulation model was developed with a finite element-based commercial software, COMSOL, to analyse the temperature distributions. Dry soybeans packed in a rectangular plastic container were used to determine the heating uniformity and validate the simulation model using a 27.12 MHz, 6 kW RF system. Both simulated and experimental results showed similar heating patterns in RF treated soybeans, in which corners and edges were more heated and the temperature values were higher in the lower part of the container. The simulation results demonstrated that the RF heating uniformity could be improved using a similar dielectric material around the samples, a smaller top plate area (similar to the sample size), and placing the samples in the middle of the two plate electrodes. The simulation model developed in this study could be applied to improve the RF heating uniformity and to optimise the treatment parameters.

Lithium–sulfur (Li–S) battery is one of the most attractive candidates for the next-generation energy storage system. However, the intrinsic insulating nature of sulfur and the notorious polysulfide shuttle are the major obstacles, which hinder the commercial application of Li–S battery. Confining sulfur into conductive porous carbon matrices with designed polarized surfaces is regarded as a promising and effective strategy to overcome above issues. Herein, we propose to use microalgaes (Schizochytrium sp.) as low-cost, renewable carbon/nitrogen precursors and biological templates to synthesize N-doped porous carbon microspheres (NPCMs). These rational designed NPCMs can not only render the sulfur-loaded NPCMs (NPCSMs) composites with high electronic conductivity and sulfur content, but also greatly suppress the diffusion of polysulfides by strongly physical and chemical adsorptions. As a result, NPCSMs cathode demonstrates a superior reversible capacity (1030.7 mA h g–1) and remarkable capacity retention...

Information on thermal death kinetics of targeted stored insects under different heating conditions is essential for developing postharvest disinfestation treatment protocols. Using a heating block system, the thermal death kinetics of adult rice weevil, Sitophilus oryzae (L.), were determined at temperatures from 44 to 50 °C at 2 °C intervals and a heating rate of 5 °C/min. The effects of heating rates (0.1, 0.5, 1, 5 and 10 °C/min) on mortality were also examined. The results showed that thermal death curves of S. oryzae followed a 0-order kinetic reaction model. The required holding times for achieving 100% mortality were 130, 50, 12, and 4 min at 44, 46, 48, and 50 °C, respectively. The activation energy for killing S. oryzae was 505 kJ/mol and the z value obtained from the thermal-death-time curve was 3.9 °C. Insect mortality after a 20 min exposure to 46 °C at low heating rates (0.1 or 0.5 °C/min) was significantly lower than that at high heating rates (1–10 °C/min). The information provided by thermal death kinetics for S. oryzae is useful in developing effective postharvest thermal treatment protocols.

In this paper, a series of composites containing of the oligo-phenol (produced by reacting of 4-methyl-phenol with dicyclopentadiene and isobutylene (MPDI)) as organic fillers, and chlorinated butyl rubber (CIIR)/acrylate rubber (AR) as matrix were prepared by melting blending method. The selective distribution phenomenon of organic fillers in the matrix and the damping properties of AR/CIIR/MPDI composites were characterized by DMA, DSC, FT-IR and SEM, respectively. The results showed that MPDI could form hydrogen bond with AR more easily than with CIIR, which resulted in MPDI dispersing preferentially in AR phase in CIIR/AR composites. And the selective dispersion of MPDI caused that the damping temperature range was orientedly broadened towards the high temperature. Specially, with the content of MPDI increased to 10 wt% in AR/CIIR marix, only the Tg of AR in AR/CIIR composites shifted to higher temperature, which reached to 55.2 degrees C, while the Tg and Tll of CIIR in AR/CIIR composites kept almost unchanged. Otherwise, the temperature range of AR/CIIR/MPDI was expanded to 100.2 degrees C with the tan d > 0.3. Therefore, it was expected as a promising way to orientedly broaden damping temperature range according to the selective distribution of organic additives in binary systems. POLYM. COMPOS., 2012. (C) 2012 Society of Plastics Engineers

Hollow porous micro/nanostructures with high surface area and shell permeability have attracted tremendous attention. Particularly, the synthesis and structural tailoring of diverse hollow porous materials is regarded as a crucial step toward the realization of high-performance electrode materials, which has several advantages including a large contact area with electrolyte, a superior structural stability, and a short transport path for Li(+) ions. Meanwhile, owing to the inexpensive, abundant, environmentally benign, and renewable biological resources provided by nature, great efforts have been devoted to understand and practice the biotemplating technology, which has been considered as an effective strategy to achieve morphology-controllable materials with structural specialty, complexity, and related unique properties. Herein, we are inspired by the natural microalgae with its special features (easy availability, biological activity, and carbon sources) to develop a green and facile biotemplating method to fabricate monodisperse MnO/C microspheres for lithium-ion batteries. Due to the unique hollow porous structure in which MnO nanoparticles were tightly embedded into a porous carbon matrix and form a penetrative shell, MnO/C microspheres exhibited high reversible specific capacity of 700 mAh g(-1) at 0.1 A g(-1), excellent cycling stability with 94% capacity retention, and enhanced rate performance of 230 mAh g(-1) at 3 A g(-1). This green, sustainable, and economical strategy will extend the scope of biotemplating synthesis for exploring other functional materials in various structure-dependent applications such as catalysis, gas sensing, and energy storage.

Effects of carbon sources (Na2CO3, NaHCO3 and glucose) and concentration of NaHCO3 on the growth density and lipid contents of Nannochloropsis oculata were studied. N. oculata preferred inorganic carbon to glucose, the growth density and lipid content of algae cultured with NaHCO3 were higher than that with glucose. The effects of concentration of NaHCO3 on growth density and lipid content were related to inoculation density and nitrogen level. In high nitrogen level, the concentration of NaHCO3 had little effect on the growth density, but in low nitrogen level, the growth density increased at first, and then decreased with the increase of concentration of NaHCO3. Based on the results we suggest that an optimum ratio of carbon to nitrogen was existed. Furthermore, we found the optimum ratio was changed with inoculation density. The optimum ratio of carbon to nitrogen was 3 when inoculation density was OD440 of 0.10, the optimum ratio increased to 5 with OD440 of 0.70. Concentration of NaHCO3 and ratio of carbon to nitrogen had significant effects on the lipid content and productivity. Lipid content reached the highest value when the ratio of carbon to nitrogen was 1 with experimental range of nitrogen level and inoculation density. The lipid productivity was 56.7 mg/(L.d) , and the EPA productivity was 6.5 mg/(L.d) at optimum cultivation condition with NaHCO3 as carbon source, the ratio of carbon to nitrogen at 1, the concentration of NaNO3 at 0.225 g/L, and the inoculation density with OD440 of 0.70.