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Arginine in grape juice can be metabolized by wine yeasts and malolactic bacteria to precursors of ethyl carbamate, a known carcinogen. The aim of this study was to develop a simple, fast and accurate method for determining arginine in grape juice with Sakaguchi reaction following the separation of arginine with Amberlite IR120 strong cation-exchange resin. Measurement was done under optimized conditions as follows: sample (mg) to cation-exchange resin (g) ratio of 0.683, sample pH 2.0, sample flow rate 0.5 mL/min, use of distilled water rinsing to avoid interference of other compounds adsorbed on the resin, and elution with 1 mol/L of NaOH solution. This method can be applied in a quick and accurate quantification of arginine in grape juice for controlling the ethyl carbamate level in wine.

Ochratoxin A (OTA) is a very important mycotoxin. However, there are few studies on the removal of OTA in wine because of the great influence on product quality and difficulty in practical application. A nano-MgO-modified diatomite ceramic membrane (MCM) with a high positive charge was prepared and applied to remove OTA in wine. The isotherm adsorption between the positively charged membrane and OTA was in accordance with the Langmuir model, with a maximum adsorption capacity of 806 ng/g at 25 °C. All of the changes in adsorption enthalpy (ΔH), adsorption free energy (ΔG) and adsorption entropy (ΔS) were negative, which indicated that the combination of nano-MgO MCM and OTA was a spontaneous exothermic and nonspecific physical adsorption process. The concentrations of OTA in adsorption-treated wines were lower than 2 μg/kg, and the removal rates exceeded 92%. After OTA removal, the composition of wines was preserved to some extent.

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Cloud computing is the emerging industry that develops rapidly at present, with extensive development prospect; however, the challenge to security technology that it faces is unprecedented. In this paper, the author analyzed the technical characteristics of cloud computing and the security problem at present, put forward the idea to establish the information security system architecture of vertical stratification and horizontal integration from the multiple perspectives of security technology, security management specification and safety laws & regulations, etc..

Arginine in grape juice can be metabolized by wine yeasts and malolactic bacteria to precursors of ethyl carbamate, known as carcinogen. The aim of this study was to develop a simple, fast, and accurate method for determining arginine in grape juice with Sakaguchi reaction by separating arginine with strong cation-exchange resins. Parameters were optimized including the concentrations of 8-hydroquinoline and sodium hydrobromite. The color stability lasted for 4 min, which is sufficient to finish the measurement. The method is simple, reproducible and accurate, and can be applied for quick measurement of arginine in grape juice to take necessary measures for controlling the level of ethyl carbamate.

Among the interfacial transport modulations to the LaAlO3/SrTiO3 (LAO/STO) heterostructure, mechanical strain has been proven to be an effective approach by growing the LAO/STO films on different substrates with varying lattice mismatches to STO. However, this lattice-mismatch-induced strain effect is static and biaxial, hindering the study of the strain effect in a dynamic way. In this work we realize dynamic and uniaxial strain to the LAO/STO oxide heterostructure at low temperature, through mechanical coupling from a magnetostrictive template. This anisotropic strain results in symmetry breaking at the interface and induces further splitting of the electronic band structure and therefore produces different conductivities along the x and y in-plane directions. In particular, we observe that along the strained direction the interface conductivity decreases by up to 70% under a tensile strain, while it increases by 6.8% under a compressive strain at 2 K. Also, it is revealed that the modulation on the interfacial transport property can be anisotropic, i.e., the resistance changes differently when an excitation current is parallel or perpendicular to the strain direction. This approach of strain engineering provides another degree of freedom for control of transport properties of oxide heterostructures and opens an additional way to investigate strain effects in materials science., Comment: 21 pages. 9 figures, main manuscript plus supporting information

Synthesis and growth properties of the TiSi2 film on a Si (001) substrate are investigated. A novel two-step method is used for deposition of the C54 phase TiSi2 film with low resistivity. The first step is the formation of the C49 phase TiSi2 at a relative low substrate temperature of 400 C, followed by rapid thermal annealing process at 850degrees C in N-2 for the formation of the C54 phase TiSi2 as the second step. Finally, selective wet, etching is employed to remove the un-reaction Ti on the surface and the low resistivity C54 TiSi2 film can be obtained. The films deposited under various parameters are evaluated by scanning electron microscopy, x-ray diffraction and the resistivity measurement. Compared with other sputtering technologies used commonly for TiSi2 synthesis, this two-step method has apparent advantages such as the mild synthesis temperature and the high purity of the final product with low resistivity, uniform large area and improving surface roughness. In addition, the film also shows that the low coefficient of resistivity-temperature appears in the temperature range from 20degrees C to 800degrees C.