Applied Mechanics and Materials Vol. 525

Abstract: To improve the miscibility of cinnamon oil with water, this study uses microcrystalline chitin as the surfactant to prepare cinnamon oil nanoemulsion. Firstly, use isopropyl alcohol and concentrated phosphoric to act with chitin, disperse molecular crystal structure of chitin, and then use hydrochloric acid for decalcification, and prepare microcrystalline chitin through centrifugation, washing, freezing and drying. Dissolve it in acetic acid solution as emulsification, and dissolve cinnamon oil in anhydrous ethanol, and mix both of which to obtain emulsion by drops. Judge the emulsification process and results of microcrystalline chitin on cinnamon oil through conductivity data. The conductivity decreases gradually to 0 from 1.4μS·cm^-1. At room temperature, the solution is aqueous liquid without stratification and precipitation, but has good stability.

Abstract: Nickel-cobalt alloy coatings were prepared on copper substrates by electrochemical deposition at various deposition current densities of 10, 20, 30, 40 and 50 mA cm^-2. Ni-Co alloy coating have been prepared by elecrodeposition technique due its low cost, easily maintainable equipment, easy control of film thickness and the method is also environmentally friendly. The effect of current density on deposit composition, structure, morphology and microhardness of electrodeposited Co-Ni alloy deposits were studied and discussed. The values of the current efficiency obtained are in the range of 68 95 %. From surface morphology obtained the current density increasing promotes the formation colony structure. Increasing the current density led to finer grain structure in Ni-Co deposit. The microhardness of electrodeposited Ni-Co coatings are in the range 482-610 HV.

Abstract: The research status of high purity magnesium oxide preparation is introduced in this paper. First, process for preparing high purity MgO is summarized, the global and domestic production status of high purity magnesia is also described. Finally, the problems and disadvantages of current MgO preparation methods are concluded, also development direction of preparation method basing on brine utilization in the production of MgO is put forward.

Abstract: Template method was used to prepare ordered mesoporous alumina, and with purchased γ-Al₂O₃ contrast. BET results showed that the specific surface area and average pore diameter of the mesoporous Al₂O₃ were 226.95 m².g^-1 and 3.91nm respectively, and with higher degree of order. XRD results showed that the cat-P catalyst with the carrier of prepared ordered mesoporous alumina hold small active component grains, which means better dispersion. H₂-TPR results showed that the SMSI effect of cat-P catalyst was stronger than that of cat-B. Stability tests showed that cat-P catalyst in 50h experiment showed high activity and stability, and the conversion of CH₄ and CO₂ were above 90% and 95% respectively among the reaction time, and the deactivation rate of CO₂ was 0.05%/h only. From TG-DTG curve could be seen that the deposition carbon on cat-P catalyst after 48h reaction was in whisker form, which did not cover the active sites and had little influence on the activity and stability of the catalyst.

Abstract: Based on the carbide material characteristics of two low and three high and its process characteristics, analysis the carbide milling cutter is easy to form crack defects in the grinding process. Through a briefly introduce the milling mill grinding process, the cemented carbide milling cutter grinding cracks are produced by a variety of reasons are detailed researched; Based on the causes of crack of the carbide milling cutter, the feasible preventive measures are put forward. And these research results can significantly reduced the crack phenomenon in the process of milling cutter grinding in corresponding enterprises, and which is of great significance for reducing the production cost for enterprises.

Abstract: Different sole materials impose very important influences on athletes movement effects. Sole materials of tennis shoes to a large extent decide athletes start and sudden stop etc. Through the study of the influences of common abrasion resistant rubber, DRC abrasion resistant rubber and adiWEAR composite of tennis shoe soles on non-slip performance of the tennis shoes, it is concluded that DRC abrasion resistant rubber has the best effect on sudden stop of athletes; common abrasion resistant rubber is more beneficial to abrupt changes in athletes movement than adiWEAR composite, but in terms of start and acceleration, common abrasion resistant rubber is worse than adiWEAR composite. Meanwhile, common abrasion resistant rubber has better support effects for long-time competitions and is more beneficial to diversified movement changes of athletes.

Abstract: Tennis has gradually become a very important leisure and entertainment project, and it has been popular among the extensive tennis fans. People pay close attention to the tennis materials and keep doing research all the way. Since the beginning of tennis, the tennis materials has been changed constantly, which ranges from the initial wood to the gradually emerging new macromolecule polymer material. The new macromolecule polymer material is of high intensity, toughness and antiknock, which is rather applicable to the tennis design technology. However, so far due to that the macromolecule polymer materials cost is higher, its promotion is limited in certain scope, and mainly be selected by the professional competition tennis players. And most of the tennis fans generally are in favor of the traditional tennis racket. This paper conducts comparing on the traditional material of tennis racket with the macromolecule polymer material of tennis racket, and makes it stand out so as to display the wide prospect of the application of the new macromolecule polymer material in the tennis design technology.

Abstract: The upper part and lower part of rice straw were respectively used as raw materials to prepare composites with poly (vinyl alcohol) (PVA) by hot-pressing at 140°C for 10 min. The performance differences of two kinds of composites were studied. Results showed that composites prepared with upper-part rice straw had higher tensile strength, strength at tensile break and hardness than that with lower-part rice straw. But the tensile elongation of composite prepared with upper-part rice straw was lower than that with upper-part rice straw. Difference ratio of tensile strength is higher than 6% and difference ratio of tensile elongation is higher than 16%. These differences were related to morphology and structure of upper-part rice straw and lower-part rice straw. Two parts of rice straw are both hollow, but upper-part rice straw has thinner holes. So the defect ratio of composite prepared with upper-part rice straw was low.

Abstract: It is found that the fluorescence of curcumin is greatly enhanced by La³⁺ in the prescence of sodium dodecyl benzene sulfonate (SDBS). Based on this, a sensitive fluorimetric method for the determination of curcumin in aqueous solution is proposed. In the HOAc-NaOAc buffer, the fluorescence intensity of curcumin is proportional to the concentration of curcumin in the range of 0.0074-7.4μg·mL^-1 and the detection limit is 3.66ng·mL^-1. The actual samples are satisfactorily determined.

Abstract: Herein we describle a facile synthesis of sulphonic acid oxime esters in acetonitrile from the corresponding sulphonic acids and oximes catalyzed by the environmental friendly 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate (TBTU) in the presence of triethylamine (TEA) under mild conditions. The present approach offers the advantages of a clean reaction, simple methodology, employing readily available catalyst, short reaction duration, high selectivity and high yield.