Advanced Materials Research Vols. 396-398

Abstract: Isoamyl acetate was synthesized from isoamylol and glacial acetic acid with strong acidic cation exchanger as catalyst. The effects of reaction conditions such as acid-alcohol ratio, reaction time, catalyst dosage to esterification reaction have been investigated and the optimum reaction conditions can be concluded as: the molar ratio of acetic acid to isoamylol 0.8:1, reaction time 2h, 25 % of catalyst (quality of acetic acid as benchmark). The conversion rate can reach up to 75.46%. The catalytic ability didn’t reduce significantly after reusing 10 times and the results showed that the catalyst exhibited preferably catalytic activity and reusability.

Abstract: 5-Phenyl-1-H tetrazole was synthesized by catalytic [3+2] cycloaddition with benzonitrile and sodium azide. Indium trichloride was used as an efficient catalyst.

Abstract: It is necessary to control hydraulic fracture height growth by creating artificial barrier for reservoir with thin payzone or weak overburdens and underburdens. In this paper, the influential factors on resistance role of artificial barrier were firstly identified and the parameters value range was determined. Then, an affixing intermediate container was combined into the core flow test device in order to ensure buoyant diverter well dispersed into carrying fluid in experiment test, and the particle size distribution of buoyant additives was tested by Malvern laser counter. The crack was made about 2/3 length in artificial core for simulating artificial barrier process by core flow test which were accomplished in base of recommendation practice of petroleum industry. Lastly, successive regression method was applied and a statistical relationship of the barrier strength with carrying fluid viscosity, floating additives concentration and core permeability. Then scouring experiments are made under modeling hydraulically fracturing treatment conditions. It was proven that the artificial barrier was steady at current treatment parameters and that could be effectively controlled hydraulic fracture height growth.

Abstract: An innovative machine tool of trussed type is introduced in this paper. It has many advantages such as light weight, rapid traverse speed and so on. But as a new type of machine tool in structure, investigation of it is not enough and further efforts are still needed. With the development of manufacturing technology, higher and higher demands of machine tool are required, and more efforts should be put on research in order to reinforce the performance of it, such as the static and dynamic stiffness, the dynamic performance and natural frequency, frequency characteristic, and so on.

Abstract: A new purple photochromic diarylethene compound, [1- (2-ethyl-3-benzothienyl)-2-(1,3,5-trimethyl-4-pyrazolyl)]perfluoroclopentene (1a), was synthesized and its photochemical properties were investigated in detail. The results demonstrated that the compound has good photochromism in PMMA amorphous film and fluorescence switching properties.

Abstract: The recognition properties of a series of novel photoresponsive azo molecular tweezers containing ester bonds or amido bonds (1-5) for neutral small molecules were investigated. The results indicate that their cis-form show good selectivity for p-nitroaniline.

Abstract: The mechanism of the reaction of the monobromocarbene (¹CHBr) with ³O₂ was studied theoretically at the B3LYP/6-311++G(d,p) level on the singlet potential energy surface (PES). All structures of the stationary points (reactants, intermediates, transition states and products) were optimized and their energies were obtained. Three product channels, P₁ (HCO + BrO), P₂ (CO₂ + HBr) and P₃ (CO + HOBr), are found. P₂ (CO₂ + HBr) is the most favorable one both kinetically and thermodynamically.

Abstract: This study reported the feasibility of adsorption of heavy metals using dry garlic stem, an environmentally-friendly and natural adsorbent．Using batch adsorption technique, the efficiency of the adsorbent was studied under different experimental conditions by varying parameters such as pH, initial concentration and contact time. The results show that at pH 2.03, adsorption temperature 35°C, the adsorption time 90 min and the amount of garlic stem 1.0 g, Pb²⁺ have the maximum adsorption capacity. The maximum adsorption capacity of the Pb²⁺ on garlic stem is 28.42 mg/g and the adsorption rate is 94.74%. At pH 4.05, the adsorption time 120 min and the amount of garlic stem 1.0, Cu²⁺ have the maximum adsorption at the same temperature. The maximum adsorption of the Cu²⁺ is 20.90 mg/g and the adsorption rate is 69.75%. The dry garlic stem was found to be efficient in removing lead and copper from aqueous solution as compared to other adsorbents already used for the removal of these ions.

Abstract: Regarded planar linkage mechanism kinematic target and execution of kinematic pair constraint reaction restrictions as the quantitative objectives, established the comprehensive dynamic design fitness function with the distance between a kinematics target and execution of a set of practical movement points, and the difference between actual constraint reaction of kinematic pair and its limit. According to multi-branch tree expression and random configuration method to create mechanical initial population, driven by the fitness function, made the mechanical population evolution towards the target requirements by the use of copy, crossover and mutation operators of genetic program. In the evolutionary process, inserted kinematics and dynamics automatic analysis technique, design examples indicated that using a genetic program can search parallel in different mechanical configuration space, dimension space and inertia space, automatically searched to such kinds of mechanisms approximate kinematics target and dynamics requirements, thus fulfilling the dynamics automatic design.

Abstract: It is very necessary to establish a kind of rapid and accurate method about detecting crystal violet for food security. In this paper, we summary the present progress in analyzing the crystal violet from three respects: sample pretreatment, detection tool, and quantitative calculation method, puts forward the direction of future development on the detection and analysis of crystal violet in aquatic products ,and gives some suggestions on it. It has certain reference value on the detection and analysis of relevant research.