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Introduction To deliver specific antigens in tumor immunotherapy, tumor cell lysates are commonly used to sensitize dendritic cells (DCs). However, the lysates possess low immunogenicity and contain many types of non-tumor-related antigens, which may induce autoimmune diseases. Tumor antigen peptides can provide high specificity but are expensive and their short half-lives limit their clinical application. Methods In this study, we used adenovirus to transfer the carbonic anhydrase IX (CA9) gene into DCs to generate specificity to renal cell carcinoma (RCC) which is the most common space-occupying lesion in humans. Inhibition of antigen presentation attenuators (iAPA) technology was also used to enhance the DC delivery capacity. Finally, DCs were co-cultured with cytotoxic T-lymphocytes (CTLs) and the anti-tumor effects were evaluated. Results The results showed that the CA9-DC-CTLs possessed a high specificity to CA9-positive cells and showed stronger anti-tumor activity than GFP-DC-CTLs both in vitro and in vivo. Discussion These findings may suggest a novel treatment option for RCC.

Ganoderma lucidum mycelia are rich in active substances such as triterpenoids and sterols. However, reports on the development of effective submerged fermentation processes are lacking and the resulting total triterpene and sterol yield is still quite low. In this study, a new G. lucidum strain G0017 mycelium isolated by screening was studied in a 3-L fermenter to investigate the effect of aeration rate in liquid submerged fermentation production of triterpenoids and sterols. By fitting the specific mycelial growth rate and the specific production rate of the triterpenoid and sterol model, an effective multistage aeration rate control process for triterpenoid and sterol fermentation production was developed. This process was validated and proven in 3-L and 50-L fermenters. The resulting yields of triterpenoids and sterols were 3.34 and 3.46 g/L, respectively, which were 69.54% and 75.63% higher than the fixed aeration rate of 1.50 volume of air per volume of liquid per minute. This optimized fermentation production process conceivably could be applied to larger-scale industrial production and perhaps also to improve liquid submerged fermentation processes with relevant edible and medicinal mushrooms.

1-Ally-3-methylimidazolium chloride ([Amim]Cl), dimethyl sulfoxide (DMSO), and CaCl2 were selected to construct dissolution systems to produce value-added products from pretreatment of waste corrugated cardboards (P-WCCs). The dissolution behaviors of P-WCCs before and after ball milling were studied in different dissolution systems. The regenerated cellulose films were quickly and efficiently prepared via dissolving, regenerating, and pressurized drying. When 4 wt % waste corrugated cardboard was dissolved in [Amim]Cl for 4 h at 90 °C, the regenerated cellulose films featured tensile strengths as high as 59.00 MPa. Adding 40% DMSO and 2 wt % CaCl2 increased the tensile strength of the film to a maximum value of 85.86 MPa. This demonstrates that DMSO improves the ability of WCC to dissolve in ionic liquids; Ca2+ improves the tensile strength and thermal stability of the regenerated cellulose film but reduces its transparency. This work provides a new, simple, and highly efficient way to use WCCs for packaging and wrapping.

Chlorine dioxide is classified by the World Health Organization as a fourth-generation A1, widely used, safe, and effective disinfectant. It is widely used in bleaching, water treatment, oil extraction, aquaculture, plants, fruits and vegetables, meat products, preservation of aquatic products, food sterilization and sterilization industries. The technology of chlorine dioxide produced by the combination reduction method is widely used in domestic papermaking related companies. In order to promote the application of chlorine dioxide, the effects of storage conditions on the stability of chlorine dioxide solution prepared by the combination reduction method and the experimental study of decomposition kinetics were studied. Experiments have shown that high temperature, high pH and high initial concentration accelerate the decomposition of chlorine dioxide solution, and the addition of sodium dihydrogen phosphate (NaH2PO4) and dimethyl sulfoxide (DMSO) can inhibit the decomposition of chlorine dioxide. The kinetic experiments showed that the decomposition rate of chlorine dioxide was secondary to ClO2 and was −0.406 for [ H + ] [{\mathrm{H}^{+}}] . The apparent activation energy of chlorine dioxide solution decomposition reaction was 26.7 kJ·mol−1, and the decomposition rate equation of chlorine dioxide was established.

Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are components of fine particulate matter associated with adverse health outcomes. However, limited work has examined the effects of PM constituents on mortality risk. Our multiple regression analysis evaluated the association of estimated neighborhood-level average fine particulate matter (PM2.5), BC, and PAH concentrations for 2013 obtained from local-scale land use regression models with 2007–2011 census tract-level age-adjusted non-accidental, cardiovascular, pulmonary, cancer, and other mortality rates in Allegheny County, PA. Models were further adjusted for census tract-level race, education, and health insurance status. In our adjusted models, estimated pollutant concentrations were not consistently associated with mortality. Only one model’s effect estimate did not include the null value, although the relationship was opposite of our original hypothesis. An interquartile range (0.25 μg/m3) increase in BC concentration was associated with a 5.9% (95% CI − 11.07, − 0.36%) decrease in log-transformed cancer mortality. However, in all mortality categories, education and health insurance covariates had a robust association with outcomes. We did not find a consistent relationship between pollutant exposures and age-adjusted mortality rates in Allegheny County, PA. However, having health insurance and having greater than a high school diploma were associated with lower mortality risk.

A long-acting and slow-release material for chlorine dioxide, based on bagasse pulp (BP) was prepared with a superabsorbent resin as the slow-release substrate and agar as the cross-linking agent. The stable ClO2 solution and the acidic activator were locked into the network structure of the superabsorbent resin, which was prepared with a carboxymethyl cellulose made from bagasse pulp. Because of the network structure of the resin, the diffusion resistance was greatly increased, and the effective release time was up to 2 months. The mechanism for the release process of the ClO2 was explored, and a kinetic model was established based on modified Fick’s diffusion law. The results showed that the release process was a diffusion-controlled process. When compared with a zero-order kinetic model and a Higuchi model, the new established model had better fitting results, and it more fully reflected the release patterns and characteristics of the ClO2.

A uniform LiF/Li–M alloy functional interfacial layer based on chemical modification effectively stabilizes LMBs by inhibiting the growth of Li dendrites., Using highly dispersed metal fluoride nanoparticles to construct a uniform fluorinated alloy type interfacial layer on the surface of Li metal anodes is realized by an ex situ solution chemical modification method. The fluorinated alloy-type interfacial layer can effectively inhibit the growth of undesirable Li dendrites while enhancing the performance of Li metal anodes.

As an excellent material for candidate coolant of the molten salt reactor, the activation of 2LiF-BeF2 is an important issue and should be concerned. In this paper, the activation of 2LiF-BeF2 has been analyzed based on a specific Molten Salt Reactor. And combined approaches, Monte Carlo method for neutron transport and extension of the Euler for inventory calculation, have been adopted. The short life nuclides for shielding design, the long-life nuclides for occupational radiation exposure management and 3H, 14C production for environment protection have been studied.

Teeth arise from the tooth germ through sequential and reciprocal interactions between immature epithelium and mesenchyme during development. However, the detailed mechanism underlying tooth development from tooth germ mesenchymal cells (TGMCs) remains to be fully understood. Here, we investigate the role of Wnt/β‐catenin signalling in BMP9‐induced osteogenic/odontogenic differentiation of TGMCs. We first established the reversibly immortalized TGMCs (iTGMCs) derived from young mouse mandibular molar tooth germs using a retroviral vector expressing SV40 T antigen flanked with the FRT sites. We demonstrated that BMP9 effectively induced expression of osteogenic markers alkaline phosphatase, collagen A1 and osteocalcin in iTGMCs, as well as in vitro matrix mineralization, which could be remarkably blunted by knocking down β‐catenin expression. In vivo implantation assay revealed that while BMP9‐stimulated iTGMCs induced robust formation of ectopic bone, knocking down β‐catenin expression in iTGMCs remarkably diminished BMP9‐initiated osteogenic/odontogenic differentiation potential of these cells. Taken together, these discoveries strongly demonstrate that reversibly immortalized iTGMCs retained osteogenic/odontogenic ability upon BMP9 stimulation, but this process required the participation of canonical Wnt signalling both in vitro and in vivo. Therefore, BMP9 has a potential to be applied as an efficacious bio‐factor in osteo/odontogenic regeneration and tooth engineering. Furthermore, the iTGMCs may serve as an important resource for translational studies in tooth tissue engineering.

Oxidative stress, which is an early determinant of Alzheimer's disease (AD), is involved in mediating neuronal apoptosis in Aβ-induced cell death. C60 fullerenes are known to behave like a ”radical sponge” as they can sponge tip free radicals and act more effectively than other antioxidants. PEO-C60-3, a C60 fullerene derivative, was investigated against β-amyloid (Aβ)(subscript 25-35)-induced toxicity toward Neuro-2A cells in this study. PFG-C60-3 reduced Aβ(subscript 25-35)-induced cytotoxicity, which showed an increasing cell viability with C60 and Aβ(subscript 25-35) co-treated cells. Moreover, the intracellular reactive oxygen species (ROS) accumulation caused by Aβ-treated Neuro-2A cells was reduced by PEG-C60-3 co-treatment. Microarray for the analysis of gene expressions was investigated. Endoplasmic reticulum (ER) stress responsive genes, ion-channel, cell-cycle and anti-oxidant related cell responses were found to be associated with C60 protective mechanism against Aβ(subscript 25-35) treatment. The results offered new comprehension into the possible pathway of Aβ(subscript 25-35) gene expression and C60 protective mechanism. With the understanding of the roles of Aβ and C60 in cells, we can hopefully provide insight on therapeutic design using C60 fullerene nanoparticles against Aβ-associated diseases.

This study investigated the effectiveness of cellulose nanocrystals derived from cassava residues as a reinforcement to starch films. Thermoplastic starch films are biodegradable to a certain extent, but the scope of their applications is limited due to their strong water absorption and poor mechanical properties. Therefore, we used abandoned cassava residues to prepare cellulose nanocrystals quickly and efficiently using a mechanochemical method. Their average diameter and length were 6.281 nm and 437.232 nm, respectively, with an aspect ratio of 70; this average size is smaller than that of CNCs obtained via acid hydrolysis. Cellulose nanocrystals were ester modified using soybean oil to improve their polarity and hydrophobicity. Thermoplastic starch-based composite films were prepared using the film casting method; the mechanical and wettability properties of these films were investigated, by controlling the concentration of modified cellulose nanocrystals in the films. Scanning electron microscopy results showed that M-CNCs were evenly distributed in the composite films; thermal stability analysis showed that composite films exhibited high thermal stability; Fourier transform infrared spectroscopy results showed that the structure of cellulose nanocrystals prepared using a mechanochemical method was stable; water contact angle measurements showed promising hydrophobic effects at a contact angle of 105.7°. Moreover, mechanical tests showed that the tensile strength of the composite film increased by 73%. Therefore, soybean-oil-modified cellulose nanocrystals were excellent reinforcing agents for thermoplastic starch films, effectively improving the overall performance of the films.

Because of its non-toxic, pollution-free, and low-cost advantages, environmentally-friendly packaging is receiving widespread attention. However, using simple technology to prepare environmentally-friendly packaging with excellent comprehensive performance is a difficult problem faced by the world. This paper reports a very simple and environmentally-friendly method. The hydroxyl groups of cellulose nanofibrils (CNFs) were modified by introducing malic acid and the silane coupling agent KH-550, and the modified CNF were added to cassava starch as a reinforcing agent to prepare film with excellent mechanical, hydrophobic, and barrier properties. In addition, due to the addition of malic acid and a silane coupling agent, the dispersibility and thermal stability of the modified CNFs became significantly better. By adjusting the order of adding the modifiers, the hydrophobicity of the CNFs and thermal stability were increased by 53.5% and 36.9% &plusmn, 2.7%, respectively. At the same time, the addition of modified CNFs increased the tensile strength, hydrophobicity, and water vapor transmission coefficient of the starch-based composite films by 1034%, 129.4%, and 35.95%, respectively. This material can be widely used in the packaging of food, cosmetics, pharmaceuticals, and medical consumables.

Aims This study aimed to explore that the human neural stem cell derived extracellular vesicles (hNSC-EVs) have therapeutic effect on neuronal hypoxia-reperfusion (H/R) injured neurons in vitro by mediating the nuclear translocation of NF-E2-related factor 2 (Nrf2) to regulate the expression of downstream oxidative kinases. Main methods The neuroprotective effects of hNSC-EVs were evaluated in an in vitro neuronal H/R model. Three parameters of hNSC-EVs, structure, phenotype and particle size, were characterized. At the cellular level, a human neuron cerebral ischemic reperfusion (CIR) injury model was constructed. Cell viability, apoptosis, and the amount of reactive oxygen species (ROS) were detected using real-time cell analysis (RTCA), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and dichloro-dihydro-fluorescein diacetate (DCFH-DA), respectively. The neuronal axonal elongation was assessed by Opera Phenix™ screening system. The angiogenesis of human umbilical vein endothelial cells (HUVECs) was evaluated by co-culturing HUVECs with hNSC-EVs in Matrigel. The expression of apoptosis and oxidative stress-related proteins in cells and the nuclear transfer of Nrf2 following hypoxia-reperfusion (H/R) was verified by Western-blotting. Key findings We found that the hNSC-EVs can promote the survival of post-H/R injury neurons, inhibit neuronal apoptosis, and enhance nuclear transfer of Nrf2, in response to oxidative stress. We also found the hNSC-EVs can promote the elongation of neuronal axons and the angiogenesis of HUVECs. Significance At present, there is no effective therapy for CIR injury. We suggest that the hNSC-EVs could be considered a new strategy to achieve nerve repair for the treatment of neurological diseases, especially stroke.

This review summarizes the preparation methods of cellulose nanofibrils (CNFs) and the progress in the research pertaining to their surface modification. Moreover, the preparation and surface modification of nanocellulose were comprehensively introduced based on the existing literature. The review focuses on the mechanical treatment of cellulose, the surface modification of fibrillated fibers during pretreatment, the surface modification of nanocellulose and the modification of CNFs and their functional application. In the past five years, research on cellulose nanofibrils has progressed with developments in nanomaterials research technology. The number of papers on nanocellulose alone has increased by six times. However, owing to its high energy consumption, high cost and challenging industrial production, the applications of nanocellulose remain limited. In addition, although nanofibrils exhibit strong biocompatibility and barrier and mechanical properties, their high hydrophilicity limits their practical application. Current research on cellulose nanofibrils has mainly focused on the industrial production of CNFs, their pretreatment and functional modification and their compatibility with other biomass materials. In the future, with the rapid development of modern science and technology, the demand for biodegradable biomass materials will continue to increase. Furthermore, research on bio-based nanomaterials is expected to advance in the direction of functionalization and popularization.

PVDF/GO membranes were successfully casted using phase inversion method. X-Ray analysis (XRD) showed that GO was well dispersed into the PVDF membrane matrix without any agglomeration. Crystallinity of PVDF/GO membrane was lower than pristine PVDF membrane. Field Emission Scanning Electron Microscopy (FESEM) images showed that surface porosity of PVDF/GO membrane was lesser than pristine PVDF membrane. Performance of PVDF/GO membrane was tested in oily waste water at pH ranging from 4 to 10 and 2 bar operating pressure. Highest water fluxes of 290 L/m2 hr was achieved for membrane at pH 10 at 30 minutes and then decline to 165 L/m2hr at 90 minutes. Then, the used PVDF/GO membranes were cleaned chemically. The flux recovery ratio at pH ranging from 4 to 10 were almost the same which was 80% at all pH value.

Composite films of polybutylene adipate terephthalate (PBAT) were prepared by adding thermoplastic starch (TPS) (TPS/PBAT) and nano-zinc oxide (nano-ZnO) (TPS/PBAT/nano-ZnO). The changes of surface morphology, thermal properties, crystal types and functional groups of starch during plasticization were analyzed by scanning electron microscopy, synchronous thermal analysis, X-ray diffraction, infrared spectrometry, mechanical property tests, and contact Angle and transmittance tests. The relationship between the addition of TPS and the tensile strength, transmittance, contact angle, water absorption, and water vapor barrier of the composite film, and the influence of nano-ZnO on the mechanical properties and contact angle of the 10% TPS/PBAT composite film. Experimental results show that, after plasticizing, the crystalline form of starch changed from A-type to V-type, the functional group changed and the lipophilicity increased, the increase of TPS content, the light transmittance and mechanical properties of the composite membrane decreased, while the water vapor transmittance and water absorption increased. The mechanical properties of the composite can be significantly improved by adding nano-ZnO at a lower concentration (optimum content is 1 wt%).

The gas puffing performance plays a key role in repeatable discharges in the Sino-UNIted Spherical Tokamak (SUNIST) experiments. In this paper, temporal evolution of the gas pressure in the vacuum vessel and the dependence of the repeatability of plasma discharges on different timing arrangements between the gas puffing pulse and the Ohmic field have been experimentally investigated. The results show that, after a fast rising phase, the gas pressure becomes quasi-stationary. In the regime of the discharges being started up when the gas pressure has already reached the quasi-stationary state for about 37 ms, an improved repeatability of the plasma discharges is achieved.

Purification process of MG-Si was limited by the difficulties involved in reducing boron content. The possibility of removing impurity boron (B) in MG-Si using CaO–Al 2 O 3 –SiO 2 –CaF 2 slags was investigated in the present study. Different from traditional research methods, the whole melting process was carried out under atmosphere condition, which was closer to the actual production conditions. The thermodynamic and kinetic mechanisms of B removal were analyzed. Based on the ionic structure theory, the relation between ionic structure of slags at high temperature and optical basicity can be explained firstly. The parameters, including the slag optical basicity, melting time and CaF 2 content were discussed. The boron content was reduced from original 25 ppmw to 4.4 ppmw through 120 min melting with the optical basicity of 0.551 and 5 wt% CaF 2 additions.

Small amounts of multicrystalline silicon were melted in an electron beam furnace in different experimental conditions in order to investigate the oxygen evaporation behavior during the electron beam melting (EBM) process. The oxygen content level before and after EBM was determined by secondary ion mass spectroscopy. The oxygen content was reduced from 6.177 to 1.629 ppmw when silicon was melted completely at 15 kW with removal efficiency up to 73.6 %. After that, it decreased continually to

A new method for boron removal from silicon using electron beam injection (EBI) is proposed. After thermal oxidation on monocrystalline silicon (100) wafer at 1000 °C for 1 h, EBI was used to induce thermal and negative charging effects to enhance boron diffusion in the oxide film and the silicon substrate. This facilitates boron removal from the silicon substrate. The boron concentration in samples was measured by secondary ion mass spectrometry. The results show that EBI reduced the boron concentration in the silicon substrate by 4.83%.

A multicrystalline silicon ingot was obtained from metallurgical-grade silicon by vacuum induction melting and directional solidification. Based on the concentration distributions of aluminum and calcium along the growth direction, the removal mechanism of such impurities with both high saturated vapor pressures and low segregation coefficients is investigated. The results show that the removal of this type of impurities only depends on evaporation during vacuum induction melting process, thus their contents decrease significantly due to the strongly evaporation under the high temperature and high vacuum conditions. During subsequent directional solidification process, a model including both segregation and evaporation is used to simulate the concentration distribution. The results show that the impurity distribution is controlled by both two mechanisms in the initial stage of solidification and is mainly determined by segregation in the end stage due to the decrease of the diffusibility and evaporability of the impurity atoms.

This paper proposed a theoretical model to determine the thermal contact resistance (TCR) on the surfaces of silicon and copper during electron beam melting. The effect of temperature and pressure on TCR, based on specific melting process conditions, was discussed. Hertz's theory was used to analyze the characteristics of material surfaces and to calculate the relationship between the pressure and distance of contact surfaces, the real contact area and the number of contact asperities combined with the physical characteristics of the material. The geometric parameter of the theoretical model was obtained based on theoretical calculations. The TCR of the entire surface was obtained by analyzing the temperature field of silicon and copper using Ansys and TCR equations. The relationship among TCR, pressure, and temperature were found. The computational results agreed with existing experimental results.

Silicon is widely used as a raw material for production of solar cells. As a major impurity in silicon, phosphorus must be removed to 1 × 10−5 wt.%. In the present study, based on the distribution of phosphorus in a silicon ingot obtained by vacuum refining and directional solidification, the mechanism for removal of phosphorus from silicon is investigated. The results show that the distribution is controlled not only by segregation at the solid–liquid interface but also by evaporation at the gas–liquid interface, showing some deviation from Scheil’s equation. A modified model which considers both segregation and evaporation is used to simulate the distribution, matching quite well with the experimental results. The temperature and solidification rate are two important parameters that affect the overall mass transfer coefficient and the effective segregation coefficient and thus the distribution of phosphorus. A high removal efficiency and a homogeneous distribution can be obtained by adjusting these two parameters.

Two ternary copper(II) complexes of dl-threonine and polypyridyl ligands with formula of [Cu(Thr)(Byp)Cl]·H2O (1) and [Cu(Thr)(Phen)H2O]Cl·2H2O (2) were synthesized. The complexes were characterized by spectral (NMR, FT-IR, and UV–Vis), CHN elemental analysis and have been structurally elucidated by X-ray crystallography. Both of the complexes formed slightly distorted square-pyramidal coordination geometry. The electronic absorption spectra of the complexes showed a very low intensity d–d electronic band in the range of 610–620 nm in Tris–HCl/NaCl (5:5 mM) pH 7.2 buffer solution. The DNA binding interaction with calf-thymus DNA (CT-DNA) was investigated by electronic absorption spectral titration and viscosity measurements. The results revealed that the phenanthroline complex (2) interact with CT-DNA through intercalation while bipyridyl complex (1) through the groove binding mode. The calculated intrinsic binding constant (Kb) of (1) and (2) were 0.5 and 4.4 × 105 M−1, respectively. Both the complexes were found to promote efficient DNA cleavage activities at low concentration in the presence of H2O2. The results showed that (2) has the highest DNA binding and nuclease activity. Furthermore, both the complexes were tested against human colon cancer (HCT 116) and breast cancer (MCF-7) cell lines and showed a dose-dependent antiproliferation effect.

The purification of metallurgical grade silicon, especially the removal of aluminum, was investigated by electron beam melting and solidification. Small amounts of silicon raw materials were melted in an electron beam furnace with same melting time and different solidification time to obtain the distribution of Al in silicon ingot. The removal mechanisms in different stages were also discussed. The results show that the removal of Al during melting process only depends on evaporation and that during solidification process depends on both segregation and evaporation. The distribution of Al shows an obvious increasing trend from the bottom to the top of the silicon ingot when solidification time is 600 s. The removal efficiency in most area is close to that in the ingot solidified instantaneously, but the energy consumption is less, which is considered to be an effective way for the purification of silicon.

In this paper a mathematical model is developed to investigate the removal of volatile impurities in molten silicon by electron beam melting (EBM) with a high efficiency and low energy consumption. The temperature distribution of molten silicon is obtained using the commercial software FLUENT. Based on the temperature distribution, the vaporization behaviors of phosphorus and silicon are investigated by Langmiur's vaporization theory. The results show that the evaporation rate of silicon during EBM increases exponentially with the increase of beam power, while, it decreases with the increase of scanning radius. The optimal parameters are discussed from the aspect of efficiency and energy saving. The energy consumption decreases with the decrease of scanning radius and with the increase of the beam power. The optimum values are consider to be with a scanning radius of 0.0339 m and a beam power of 23.4 kW for 0.5 kg silicon when phosphorus is removed from 1.44 × 10−2 to 1 × 10−5 (wt.%).

According to the traditional metallurgical theory, the evaporation process of phosphorus and silicon during silicon refining by electron beam melting (EBM) is discussed and a theoretical model is established to obtain the loss rate of silicon, the removal efficiency of phosphorus and the corresponding energy consumption. The results show that phosphorus can be removed from silicon melt efficiently and quickly by EBM. There is a one-to-one correspondence between the loss of silicon and the removal efficiency of phosphorus, indicating that they have obvious effect on each other, whereas the EB power has little influence on the loss rate of silicon. If the EB power is increased from 9 kW to 21 kW, the melting time can be shortened by 68%, the loss of silicon increased by only 0.1% and the energy consumption decreased by 25%. Based on the theoretical and experimental results, a high-power EBM method is considered to be a better way for the removal of phosphorus with high efficiency and low energy consumption under such experiment conditions.

Solidification rate has a significant influence on purification of silicon due to segregation of impurities at a liquid–solid interface of a solidifying silicon ingot. A mathematical model is developed to evaluate time-dependent position of the liquid–solid interface and solidification rate of electron beam melted ingots. A series of solidification experiments with different cooling rates are conducted to measure position of a line which separates directionally grown columnar crystals visible in cross-sections of the solidified ingots. Results show that not the whole ingot solidifies directionally when the reduction rate of the beam current is larger than 1.67 mA/s. The position of the dividing line depends on cooling rate and the experimental trend is consistent with that resulted from theoretical simulations. Modeling shows that the solidification rate changes fast when the beam current reduces linearly that is detrimental for segregation of impurities. It also predicts that an exponential reduction of the beam current leads to a uniform solidification rate which is beneficial to segregation of impurities, though not all exponential current reductions lead to this kind of solidification behavior.

An experimental investigation into the removal of phosphorus from molten silicon using electron beam melting has been carried out. The time variation of phosphorus content is obtained at the electron beam power of 9, 15, and 21 kW, respectively. The results show that, at a constant power, the content of phosphorus decreases rapidly within the range of approximately 0–900 s after silicon is melted completely, and then tends to level out with further extension of the melting time. The content of phosphorus is decreased from 33.2 × 10 −4 wt.% to 0.07 × 10 −4 wt.% after 1920 s at a power of 21 kW, which achieves the target for solar-grade silicon of less than 0.1 × 10 −4 wt.%. Moreover, the removal reaction of phosphorus by evaporation from the surface of silicon melt during electron beam melting occurs in accordance with the first order kinetics. The mass transfer coefficients in different removal steps are calculated and discussed, which indicate the removal reaction of phosphorus is controlled by both the transport of phosphorus atom from the bulk to the melt free surface and the vaporization from the free melt surface into the gas phase.

Synthetic biopolymer blends are gaining interest in the packaging industry because the incorporation of natural materials imparts biodegradable properties to films. In this study, polyethylene/chitosan (chitosan) films with thicknesses of about 0.3 ± 0.01 mm were fabricated via compression molding. The effects of the variation in the length of compounding as a function of the length/diameter (l/d) ratio (15:1, 30:1, 45:1, 60:1, and 75:1) were investigated. The experimental results show that a higher degree of miscibility of the blends was achieved with increasing compounding length; this led to improved mechanical properties in the films, and this was verified by the statistical analysis of data with the analysis of variance procedure. The tensile strength (TS) increased by about 25%, whereas the elongation at break (Ebreak) increased by twofold. Films fabricated from blends compounded with an l/d ratio of 60:1 had the highest TS and Ebreak values, and the TS was comparable to that of low-density polyethylene films. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43796.

The enthalpies of dissolution for ammonium dipicrylamide (ADPA) in dimethyl sulfoxide (DMSO) and N-methyl pyrrolidone (NMP) were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K under atmospheric pressure. Empirical formulae for the calculation of the enthalpies of dissolution (ΔdissH) were obtained from the experimental data of the dissolution processes of ADPA in DMSO and NMP. The linear relationships between the rate (k) and the molality (b) were found. The corresponding kinetic equations describing the two dissolution processes were d α / d t = 10 − 2.38 ( 1 − α ) 0.86 for the dissolution of ADPA in DMSO, and d α / d t = 10 − 2.49 ( 1 − α ) 0.83 for the dissolution of ADPA in NMP, respectively.

This study investigates the benefits of modifying asphalt and stone-matrix-asphalt (SMA) mixtures in flexible pavement. 70/100-penetration-grade asphalt cement and 5% styrene-butadiene-styrene (SBS...

This paper investigates the viability of using starch (ST) as a new modifier for asphalt paving materials. Different ratios of ST (2.5, 5.0, and 7.5% by weight of asphalt) were blended with 70/100 paving grade asphalt. Unmodified and modified asphalt binders were subjected to physicochemical, alkali, acid and fuel resistance tests. The performance tests including, Marshall stability, Marshall Quotient (MQ), tensile strength, tensile strength ratio, flexural strength, rutting resistance and resilient modulus (MR) were carried out on unmodified and modified stone matrix asphalt (SMA) mixtures. The analyses of test results show that the performance of ST-modified asphalt mixtures are better than conventional and styrene–butadiene–styrene (SBS)-modified mixtures. The rutting potential, moisture susceptibility and temperature susceptibility can be reduced by the inclusion of ST in the asphalt mixture. The laboratory MR values are lower than the calculated ones using the empirical equations. The results also revealed that this modifier can be used as anti-stripping agent. It also shows resistance to fuels and most common chemicals. A ST content of 5% by weight of asphalt is recommended for the improvement of the performance of asphalt concrete mixtures similar to that investigated in this study.

Summary Biodegradable triblock copolymers of PEG, poly(ethyl carbonate) and acid-functional polycarbonate with precisely controlled molecular weight and well-defined structure were synthesized via organocatalytic living ring opening polymerization, and self-assembled into nanostructures with narrow size distribution. These nanostructures demonstrated exceptionally high loading capacity of an amine-containing cargo (i.e. doxorubicin, an anticancer drug) due to acid–base ionic interaction between the cargo and the polymer. To further fine-tune critical properties of drug-loaded micelles, a urea-containing polycarbonate was combined with an acid-functional polycarbonate to form mixed micelles stabilized by hydrogen bonding interactions. The mixed micelles provided greater kinetic stability, nanosize with narrow size distribution and high cargo loading capacity. These nanostructures can be used as carriers to deliver a variety of anticancer drugs that contain amine functional groups.

The present study investigates the benefits of modifying the asphalt and stone matrix asphalt (SMA) mixture in flexible pavement. Fifty/sixty penetration grade asphalt cement and four proportion of pyrolisis polypropylene (PP) were selected. Unmodified and modified asphalt binders were subjected to rheological and homogeneity tests. The performance tests including, Marshall stability, tensile strength and compressive strength were conducted on unmodified and modified SMA mixtures. The regression relationships between the performance tests were obtained. A mechanistic-empirical design approach was used for estimating the improvement in service life of the pavement or reduction in thickness of SMA and base layer for the same service life due to modification the SMA mixtures. The analyses of test results show that the performance of PP-modified asphalt mixtures are better when compared to conventional mixtures. The temperature susceptibility can be reduced by the inclusion of PP in the asphalt mixture. A PP content of 5% by weight of asphalt is recommended for the improvement of the performance of asphalt concrete mixtures similar to that investigated in this study. The results of multi-layer elastic analysis presented herein indicate that the pavement consisting of PP-modified SMA as a surface layer is beneficial in reducing the construction materials. Actual savings would depend upon the option exercised by the designer for reducing the thickness of an individual layer.

The present study investigates the potential use of pyrolysis low density polyethylene (LDPE) as a modifier for asphalt paving materials. Five different blends including conventional mix were subjected to binder testing such as rheological tests, as well as to some other tests related to the homogeneity of the system. Further, its effect on the moisture sensitivity and low temperature performance of stone matrix asphalt (SMA) mixtures was studied. Research results indicate that modified binders showed higher softening point, keeping the values of ductility at minimum range of specification of (100+ cm), and caused a reduction in percentage loss of weight due to heat and air (i.e. increase durability of original asphalt). The results indicated that the inclusion of LDPE in SMA mixtures can satisfy the performance requirement of high-temperature, low temperature and much rain zone. In addition, the horizontal tensile strain at the bottom of asphalt concrete layer (Et) and the vertical compressive strain at the top of subgrade layer (Ec) were calculated using multi-layer elastic analysis program, BISAR under 50KN set of dual tires with 106.5 mm contact radius. These responses were used for estimating the improvement in service life of the pavement or reduction in thickness of SMA and base layer for the same service life due to modification the SMA mixtures.

Ginkgo is a genus of highly unusual non-flowering plants with one extant species. The Ginkgoaceae is a family of gymnosperms which appeared during the Mesozoic Era, of which the only extant representative is Ginkgo biloba, which is for this reason sometimes regarded as a living fossil. Extracts of Ginkgo contain flavonoid glycosides and terpenoids (ginkgolides, bilobalides) and have been used pharmaceutically. Polysaccharides of G. biloba can reduce blood sugar, immune regulation, antioxidation, anti-inflammatory effects and play an important role in anti-tumor effects. At present, the method of water extraction and alcohol precipitation was generally used for the extraction of polysaccharides from G. biloba. The de-protein methods of polysaccharides were Savag’s and trichloroacetic acid method. The extracted polysaccharides were generally a mixture and usually use a combination of two or more methods to separate from proteins and other contaminants to yield pure polysaccharides. The commonly used methods for purification were the step-by-step precipitation, salting-out and column chromatography method. Polysaccharides of G. biloba were polymers of glucose, rhamnose, arabinose, mannose, galactose and xylose. In this review, we summarized previous and current researches on polysaccharides from G. biloba and provide new insights for future work on polysaccharide of this specie. Key words: Polysaccharides, Ginkgo biloba, biological activity, chemical constituent.

Viscoelasticity and microstructure of gels prepared by heating mixtures of chicken breast salt-soluble protein (SSP) and partially insolubilized whey protein concentrate (WPC) with solubilities ranging from 98.1 to 27.5% in 0.1 M NaCl, pH 7.0, were evaluated. Storage (G') and loss (G'') moduli ofsolutions containing 4% SSP, or combinations of 4% (w/w protein) SSP and 12% (w/w protein) WPC, were determined while heating from 30 to 95 o C or isothermally at 65 or 90 o C. The WPC altered the temperature and magnitude of G' and G'' transitions of SSP during heating. At 65 o C, insolubilized WPCs increased elasticity of SSP gels

Wavelength 1064 nm is one of the most widely used laser wavelengths in industries and science. The high-precision measurement of the refractive index of optical materials at 1064 nm is significant for improving the optical design. We study the direct measurement of refractive index at 1064 nm of lasers, including calcium fluoride (CaF2), fused silica and zinc selenide (ZnSe), whose refractive indices cover a large range from 1.42847 to 2.48272. The measurement system is built based on the quasi-common-path Nd:YAG laser feedback interferometry. The thickness can be measured simultaneously with the refractive index. The results demonstrate that the system has absolute uncertainties of ~10−5 and ~10−4 mm in refractive index and thickness measurement, respectively.