Applied Mechanics and Materials Vol. 473

Abstract: A new unsymmetrical photochromic diarylethene compound 1a was synthesized and its photochromism were investigated, such as photochromism and kinetics in solution. The compound exhibited good photochromism in solution with alternating irradiation by UV/Vis light, and the maxima absorption of its closed-ring isomer 1b are 515nm. The open-ring isomer of the diarylethene 1a exhibited relatively strong fluorescence at 424 nm when excited at 280 nm. Its fluorescence intensity decreased along with the photochromism from open-ring isomers to closed-ring isomers upon irradiation with 297 nm UV light.

Abstract: An unsymmetrical photochromic diarylethene which called 1-[(2-methyl-5-dioxolane)-3-thienyl]-2-[(2-methyl)-5-(4-methoxyphenyl)-3-thienyperfluorocyclo-pentene was synthesized and its photochromic properties were examined in detail. The result demonstrate that the diarylethene changed the color from colorless to blue violt upon irradiation with 297 nm UV light, in which absorption maxima were observed at 552 nm and 563 nm in hexane and PMMA films, respectively. This photochromic compound also exhibited remarkable fluorescence switching both in hexane solution and in PMMA films.

Abstract: An unsymmetrical photochromic diarylethene 1-(3-methyl-2-pyridyl)-2-[2-methyl-5-(4-formylphenyl)-3-thienyperfluoroyclopentene (1a) was synthesized, its photochromic properties were examined, The results showed that the compound exhibits good photochromism with UV/Vis light irradiation. The Diarylethene 1a changed the color from colorless to plum upon irradiation with 297 nm UV light, in which absorption maxima were observed at 560 and 535 nm in hexane and PMMA films, respectively.

Abstract: n-butanol is a basic chemical compound with lower volatility, intersolubility and higher heating value, making it suitable to be used as a potential alternative biofuel. One butanol producing strain was isolated from soil and identified by 16S rDNA sequencing. Two universal primers (27F, 1492R) were used. Squence analysis indicated 16S rDNA sequence (Accession Number KF418240) of this strain was 99% identical to that of Bacillus amyloliquefaciens. This strain was designed as Bacillus amyloliquefaciens NELB-12. Optimaization of fermentation medium composition and fermentation conditions were carried out. The optimal medium main components were 30 g/l starch, 4 g/l ammonium nitrate, and 30 g/l beef extract. The optimal fermentation cultured with working volume of 120 ml in 250 ml flask at pH 6.5, 39°C, and 100 rpm. Bacillus NELB-12 could produce butanol at higher concentration that reached 8.9 g/l with a total ABE of 12.7 g/l and showed a high butanol tolerance. B. amyloliquefaciens NELB-12 is considered as an economical and cost effective potential producer for butanol industry.

Abstract: With the continuous progress of science and technology, especially with the continuous development of material science, many new materials are applied to all kinds of sports equipment and equipment. It boosts the irreplaceable role for the development of competitive sports. This research is on the carbon fiber material model in the tennis racket on the application of analysis and discussion. The systematic study is on the characteristics of carbon fiber materials, to provide the theoretical basis for the application of the present sports equipment development of carbon fiber materials.

Abstract: In addition to be used in the manufacture of tires, rubber is also widely used in the preparation of sporting goods. In table tennis, the rubber is used in the manufacture of the rubber on the table tennis bat that it can satisfy the requirements for high elasticity and durability of the bat. With the continuous development of table tennis, and increasingly fast ball, rotating become stronger and stronger, this calls for increasingly high quality and specifications of the table tennis equipment. The table tennis bat is composed of three parts, the bottom plate, rubber and sponge, the reasonable collocation of the three determines the quality of a bat. The physical properties of table tennis pat rubber has a great influence on the quality of a bat, with regard to the production of rubber products of table tennis pat rubber, on the basis of choosing the appropriate types of rubber, by adjusting the rubber compounding and production process reasonably, that the products with the best performance can be obtained.

Abstract: Springback is a problem that must be solved in multi-point forming in this paper, finite element software ls-dyna was used to simulate plate stamping springback. 3mm thick elastic cushion inhibited dimple of sheet forming, but the use of elastic cushion and plate springback would lead to shape error. A method was proposed which modified the forming surface of element group in the Multi-point forming (MPF) by iterative ways according to the numerical simulation results. The accuracy of forming was improved after two compensation, it was proved that this method can compensate springback of the multi-point forming.

Abstract: Secondary effluent of sewage treatment plant directly reused in power plant circulating cooling water system was the main cause of scale inhibition in the system.Facing this serious scaling problem,static scale inhibition experiment was carried out to filter out the efficient compound formulation.Corrosion inhibition performance by rotary coupon experiment was studied.Scale and corrosion inhibition effect under the field condition by homemade dynamic simulation experiment and the environment toxicity were tested. The result showed that this water treatment agent gain the high scale and corrosion inhibition effect, with low phosphorus,non-toxic,friendly to environment.

Abstract: To predict the sound radiation of structures, both a structural problem and an acoustic problem have to be solved. In case of thin structures and dense fluids, a strong coupling scheme between the two problems is essential, since the feedback of the acoustic pressure onto the structure is not negligible. A popular idea for solving this class of problems is to discretizing the structural domain with the finite element (FE) method and with boundary element (BE) method on the acoustic field. A wide range of researches has been carried on the coupling the FE and BE methods. For fast prediction of sound radiation characteristic of similar structures, a coupled solver in frequency domain is presented in this essay. Numerical experiments showed acceleration on noise optimization problems of underwater structures with different materials.

Abstract: We study a two-electron system in a double-layer quantum dot under a magnetic field by means of the exact diagonalization of the Hamiltonian matrix. We find that discontinuous ground-state energy transitions are induced by an external magnetic field in the case of strong coupling. However, in the case of weak coupling, the angular momentum of the true ground state does not change in accordance with the change of the magnetic field B and remains = 0.