Reinforcement of natural rubber with core-shell structure silica-poly(Methyl Methacrylate) nanoparticles

A highly performing natural rubber/silica (NR/SiO2) nanocomposite with a SiO2 loading of 2 wt% was prepared by combining similar dissolve mutually theory with latex compounding techniques. Before polymerization, double bonds were introduced onto the surface of the SiO2 particles with the silane-coupling agent. The core-shell structure silica-poly(methyl methacrylate), SiO2-PMMA, nanoparticles were formed by grafting polymerization of MMA on the surface of the modified SiO2 particles via in situ emulsion, and then NR/SiO2 nanocomposite was prepared by blending SiO2-PMMA and PMMA-modified NR (NR-PMMA). The Fourier transform infrared spectroscopy results show that PMMA has been successfully introduced onto the surface of SiO2, which can be well dispersed in NR matrix and present good interfacial adhesion with NR phase. Compared with those of pure NR, the thermal resistance and tensile properties of NR/SiO2 nanocomposite are significantly improved.

Synthesis and characterization of tin dioxide core-shell structure nanowires

In this study, one-dimensional and quasi-one-dimensional tin dioxide nanowires and nan-owalls were fabricated by the use of the chemical vapor deposition technique. It was demonstrated that the growth and nanostructure of tin oxide can be controlled by varying the thickness of gold layer and the partial pressure of vapor at growing sites. Nanowires with a core-shell structure, i.e., pure tin core and tin oxide shell, were synthesized from C-S_nO₂ powders at a mol ratio of C/S_nO₂=3/5 on both silicon and Lanthanum Strontium Co-balt Ferrite ceramic wafers through the vapor-solid mechanism. The conditions that are favorable to the growth of core-shell structure nanowires are investigated.

Using the solid-shell element to model the roll forming of large radii profiles

Roll forming is an incremental bending process for forming metal sheet, strip or coiled stock. Although Finite Element Analysis (FEA) is a standard tool for metal forming simulation, it is only now being increasingly used for the analysis of the roll forming process. This is because of the excessive computational time due to the long strip length and the multiple numbers of stands that have to be modelled. Typically a single solid element is used through the thickness of the sheet for roll forming simulations. Recent investigations have shown that residual stresses introduced during steel processing may affect the roll forming process and therefore need to be included in roll forming simulations. These residual stresses vary in intensity through the thickness and this cannot be accounted for by using only one solid element through the material thickness, in this work a solid-shell element with an arbitrary number of integration points has been used to simulate the roll forming process. The system modelled is that of roll forming a V-channel with dual phase DP780 sheet steel. In addition, the influence of other modelling parameters, such as friction, on CPU time is further investigated. The numerical results are compared to experimental data and a good correlation has been observed. Additionally the numerical results show that the CPU time is reduced in the model without friction and that considering friction does not have a significant effect on springback prediction in the numerical analysis of the roll forming process.

Height, aging and cognitive abilities across Europe

Previous research has found that as a marker of childhood circumstances, height is correlated with cognitive functioning at older ages. Using data from the Survey of Health, Ageing, and Retirement in Europe (SHARE) and about 17,000 respondents from 11 countries, we find that height is positively and significantly associated with cognitive functioning in later life despite controlling for a myriad of possible confounding factors. A 10 cm increase in height is associated with a 0.04 standard deviation increase in a summary cognitive score (mean 0.02, std. dev. 0.77). We find that being born in a country where the infant mortality rate at the time of birth is high has a negative and significant influence on cognitive functioning in later life. A 10% increase in the infant mortality rate is associated with a 0.1 standard deviation decrease in the summary cognitive score. We also find some evidence that height serves as a protective factor against age related deterioration in cognitive functioning. For persons of average stature, age related decreases in cognition scores are 3–5 percentage points smaller if they move up a quartile in the height distribution. Our results also suggest that there is a significant positive association between height and cognitive abilities across countries for this pre-1950 birth cohort of respondents, with correlations ranging from 0.4 to 0.8.

The impact of continuous versus intermittent high frequency stimulation of the nucleus accumbens shell on ethanol preference and circadian locomotor activity in alcohol preferring rats

This study aimed to investigate the effect of different patterns of high-frequency stimulation at the nucleus accumbens shell on ethanol preference and circadian locomotor activity in adult male alcohol preferring (P) and nonpreferring (NP) rats.

Distilled technical cashew nut shell liquid (DT-CNSL) as an effective biofuel and additive to stabilize triglyceride biofuels in diesel

We report distilled technical cashew nut shell liquid (DT-CNSL) as a non-transesterified biofuel and also as an additive to convert triglycerides to biofuel, without the need for the formation of methyl esters. DT-CNSL blends of diesel obey physico-chemical parameters of diesel. DT-CNSL offers stability to blends of straight vegetable oil (SVO) and tallow oil in diesel. Fluorescence studies using charge transfer probes show that the blend of DT-CNSL, triglycerides and diesel is a uniform solution, and fluorescence behavior is similar to that of diesel. The economics for the cultivation of cashew (Anacardium occidentale), its industrial use and rich carbon sink properties indicate that DT-CNSL could complement or replace traditional biodiesel crops like Jatropha and improve income for farmers. © 2014 Elsevier Ltd.

Surface modification and properties analysis of shell powder with sodium stearate surface modifier

In this study, shell powder was modified by sodium stearate surface modifier for improving the compatibility of SP with polymer materials. The surface modifiers influence on the physical and chemical properties of SP were studied by scanning electron microscope(SEM), fourier infrared spectrum(FT-IR), surface contact angle meter, XRD diffraction analysis meter and other modern instruments and analysis method. The results showed that the surface modifier was successfully coupled to the shell powder surface. After surface modifier modification, the interfacial compatibility of the shell powder with polymer materials was effectively improved. The contact angle of shell powder surface increased from 73.5 ° to 110.8 °, along with the dosage of sodium stearate surface modifier was 4.0%. All results suggested that modified shell powder is promising for using as a reinforcement filler in polymer materials. © (2014) Trans Tech Publications, Switzerland.

Synthesis of LiFePO4@carbon nanotube core-shell nanowires with a high-energy efficient method for superior lithium ion battery cathodes

A high-energy efficient method is developed for the synthesis of LiFePO4@CNT core-shell nanowire structures. The method consists of two steps: liquid deposition approach to prepare FePO4@CNT core-shell nanowires and solvothermal lithiation to obtain the LiFePO4@CNT core-shell nanowires at a low temperature. The solution phase method can be easily scaled up for commercial application. The performance of the materials produced by this method is evaluated in Li ion batteries. The one-dimensional LiFePO4@CNT nanowires offer a stable and efficient backbone for electron transport. The LiFePO4@CNT core-shell nanowires exhibit a high capacity of 132.8 mAh g^-1 at a rate of 0.2C, as well as high rate capability (64.4 mAh g^-1 at 20C) for Li ion storage.