Influence of Inorganic Salts on the Adsorption of Cationically Modified Starch to Fibers

The article is focused on the influence of inorganic salts on the adsorption of cationically modified starch to fibers. Results show that low concentrations of inorganic salts usually affect the process of adsorption in a positive way. Adsorption efficiency at higher concentrations, however, depends on the type of inorganic salts as well as the sequence of adding inorganic salts and starch to paper suspension.

Effect of phosphorus and heat treatment on microstructure of Al-25%Si alloy

It is known that phosphorus can refine the primary silicon and heat treatment can spheroidize the eutectic silicon. This paper presents an optimal combination of heat treatment processes and P refinement on hypereutectic Al-Si alloy. The optimal P addition amount, and the solution and aging temperatures for Al-25%Si alloy were obtained through the orthogonal experiment, and their modification effects were discussed. The results show that P addition has the greatest modification effect, followed by aging temperature, and the modification effect of solution temperature is the least. The optimized modification parameters are: addition of 0.6% P, solution at 540 oC and aging at 160 oC. In addition, the cooling curve, superheating and hardness of the alloy were also analyzed.

Modification and aging precipitation behavior of hypereutectic AI-21wt.%Si alloy treated by P+Ce combination

In the present study, the tested hypereutectic Al-21 wt.%Si alloys were prepared by modifying the melt using different proportions of P and Ce, and then applying T6 heat treatment. The modif ication effects and mechanism of P+Ce complex modif ier on the Si phase of hypereutectic Al-21 wt.%Si alloy were studied, and the aging precipitation behavior after modif ication was characterized by means of tensile strength measurement, OM, SEM and TEM analysis. The results show that the massive primary silicon phase particles are signif icantly ref ined after modif ication, while the needle-like eutectic silicon crystals become f ibrous and short. It was found that the mechanism of phosphorus modifi cation on the primary silicon can be attributed to heterogeneous nucleation of Al P, while the modification mechanism of Ce can be explained by adsorbing-twinning theory. In the aged microstructure of the modif ied hypereutectic Al-21 wt.%Si alloy, there existed some strengthening phases such as Al4Cu9, Al2 Cu, AlC u3, and Al57Mn12. The P+Ce complex modif ier not only affected the size of primary silicon and eutectic silicon, but also the aging behavior of alloys under the heat treatment process. When Al-21 wt.%Si alloy was modif ied using 0.08%wt.P + 0.6wt.% Ce, the aging precipitates were dispersed uniformly in the alloy, and its mechanical properties at room and elevated temperatures are optimized(Rm = 287.6 MPa at RT, Rm = 210 MPa at 300 ℃).

Deflection modification factors of multistory buildings considering soil-structure interaction

In this investigation,attempts are made to examine the effects of soil-structure interaction on the deflection modification factor of multistory buildings and to clarify the role of deformable soil on this factor.A comprehensive study is conducted to investigate the effect of inertial interaction on displacement demand ratios in soil-structure systems with different structural characteristics and various non-dimensional parameters,using a simplified interacting model.A two-step regression analysis of the nonlinear,dynamic computer simulation results obtained,leads to a reliable and accurate formula for predicting deflection modification factors that incorporate foundation flexibility.The results illustrate that the application of deflection modification factors derived from fixed-base structures can lead to unsafe evaluation of the structures on soft soil.The proposed formula provides a useful tool for design engineers to incorporate the effect of soil-structure interaction into the evaluation of structural deformations.

Modifi cation of β-TCP/PLGA Scaffold and Its Effect on Bone Regeneration in vivo

In order to look for the best proportion of β-tricalcium phosphate（β-TCP）and poly（lactideco-glycolide）（PLGA）we fabricated porous composites β-TCP/PLGA scaffold using freeze-drying method.Morphologicalcharacterization using scanning electron microscopy showed that the interconnected pore distribution was even and there was no significant difference with the increase of PLGA content.Moreover,the porosity,compressive strength and degradation in vitro were characterized.The fabricated scaffolds with increased PLGA in the composites β-TCP/PLGA scaffolds willget stronger mechanicalproperty and better appearance,furthermore,get suitable environment for cells.According to the evaluation indexes for the tissue engineering scaffold,the group of scaffold（β-TCP/PLGA=6：4）was selected to evaluate the induced celladhesion and proliferative ability of the scaffolds.Then as transplant embed into the bone criticaldefect sites on rats femur.The repairing processes of bone defect sites were characterized by X-ray analysis within 12 weeks.X-ray analysis showed that the bone defect sites alldisplayed the formation of callus obviously,In summary,our data suggest that the scaffold（β-TCP/PLGA=6：4）has a promising clinicalfuture in regeneration of bone criticaldefects.

Effects of Surface Modifi cation on the Properties of Microcapsules for Self-healing

Poly（urea-formaldehyde）（UF） microcapsules with epoxy resin E-51 as core material used as self-healing materials were prepared by interfacial polymerization method. The surface of UF microcapsules was modifi ed by γ-（2,3-epoxypropoxy） propytrimethoxysilane（KH-560）. The interfacial interactions between UF microcapsules and KH-560 were studied by Fourier transform infrared spectroscopy（FTIR） and X-ray photoelectron spectrometric analysis（XPS） of microcapsules. The surface topography of microcapsules was characterized by scanning electron microscopy（SEM）. The thermal stability and mechanical properties were evaluated. FTIR and XPS results showed that there were physical and chemical combinations between the silicon coupling agent and the microcapsules surface. The thermal stability and mechanical property analysis showed that the addition of KH-560 could greatly improve the thermal stability, tensile property and elastic property. SEM results indicated that the addition of KH-560 could improve the bonding between the surface of microcapsules and resin matrix and improve the ability of self-healing.

Effect of algal flocculation on dissolved organic matters using cationic starch modified soils

Modified soils（MSs） are being increasingly used as geo-engineering materials for the sedimentation removal of cyanobacterial blooms. Cationic starch（CS） has been tested as an effective soil modifier, but little is known about its potential impacts on the treated water.This study investigated dissolved organic matters in the bloom water after algal removal using cationic starch modified soils（CS-MSs）. Results showed that the dissolved organic carbon（DOC） could be decreased by CS-MS flocculation and the use of higher charge density CS yielded a greater DOC reduction. When CS with the charge density of 0.052, 0.102 and0.293 meq/g were used, DOC was decreased from 3.4 to 3.0, 2.3 and 1.7 mg/L, respectively.The excitation–emission matrix fluorescence spectroscopy and UV254 analysis indicated that CS-MS exhibits an ability to remove some soluble organics, which contributed to the DOC reduction. However, the use of low charge density CS posed a potential risk of DOC increase due to the high CS loading for effective algal removal. When CS with the charge density of 0.044 meq/g was used, DOC was increased from 3.4 to 3.9 mg/L. This study suggested, when CS-MS is used for cyanobacterial bloom removal, the content of dissolved organic matters in the treated water can be controlled by optimizing the charge density of CS. For the settled organic matters, other measures（e.g., capping treatments using oxygen loaded materials） should be jointly applied after algal flocculation.

An epigenetic view of developmental diseases: new targets, new therapies

Background:Function of epigenetic modifications is one of the most competitive fields in life science.Over the past several decades,it has been revealed that epigenetic modifications play essential roles in development and diseases including developmental diseases.In the present review,we summarize the recent progress about the function of epigenetic regulation,especially DNA and RNA modifi cations in developmental diseases.Data sources:Original research articles and literature reviews published in PubMed-indexed journals.Results:DNA modifications including methylation and demethylation can regulate gene expression,and are involved in development and multiple diseases including Rett syndrome,Autism spectrum disorders,congenital heart disease and cancer,etc.RNA methylation and demethylation play important roles in RNA processing,reprogramming,circadian,and neuronal activity,and then modulate development.Conclusions:DNA and RNA modifications play important roles in development and diseases through regulating gene expression.Epigenetic components could serve as novel targets for the treatment of developmental diseases.

Aluminum Electroplating on AZ31 Magnesium Alloy with Acetic Anhydride Pretreatment

Magnesium(Mg)alloys for metal electroplating require a surface pretreatment,i.e.,the removal of the spontaneously oxidized surface layer(MgO,Mg(OH)_(2),andMgCO_(3)).However,the use of highly toxic and/or corrosive acids in conventional pretreatment processes has become an issue.In this study,a facile and less toxic pretreatment is demonstrated and applied in aluminum(Al)electroplating.The immersion of the AZ31 Mg alloy into acetic anhydride(Ac_(2)O)removed the spontaneously oxidized surface layer and formed a thin but stable magnesium acetate(Mg(OAc)_(2))layer that protects the metal substrate from further oxidation.The Al electroplating bath is a concentrated diglyme(G2)-AlCl_(3)organic solution that can readily dissolve Mg(OAc)_(2)to enable direct plating onto a metal substrate.The as-deposited Al layer has a compact and crack-free morphology that improves the corrosion resistance and hardness(2.7 GPa).Owing to the lack of an interfacial oxidized layer,heat treatment led to the successful diff usion of Mg and Al atoms,which increased the hardness to 4.4 GPa.The Ac_(2)O pretreatment of Mg alloys enables the successful Al electroplating and subsequent heat treatment.