Key Engineering Materials Vols. 480-481

Abstract: A fluorine-silicon polymer (PFAMS) with pendant perfluoroalkyl and reactive epoxy groups was firstly synthesized by bulk polymerization (Si-H additional reaction) of polymethyltrifluoropropylsiloxane (PFHMS), allylpolyoxyethylene ether (AGE) and perfluorooctyl ethylene (PFOE). Then amino-functionalized nano silica (KH550-SiO2) was prepared via sol-gel method by 3-aminopropyltriethoxylsilane (KH550) and tetraethyl orthosilicate (TEOS). Finally novel fluorosiloxane polymer/silica hybrid nanocomposites (PFAMS-SiO2) were fabricated through graft copolymerization method by the above two chemicals, PFAMS and KH550-SiO2 and super-hydrophobic cotton fabric was also constructed with contact angle of water on its surface 160.91° through immersing-padding-baking processes. Chemical structure, thermal performance, micro-morphology and hydrophobic property of the hybrid materials and film were investigated by Fourier Transform Infrared Spectrum (FT-IR), Thermogravimetric Analyzer (TGA), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM) and Static contact angle analyzer, respectively. Results show that a hydrophobic film and many lotus-leaf-like micro-nano scale tubercles are coated on the surface of cotton fabrics.

Abstract: Preparation of semi-solid Sn–58Bi alloys by mechanical stirring casting method was investigated. The effect of temperature below the melting temperature on the microstructures and mechanical properties of semi-solid Sn–58Bi alloys was discussed. The experimental results showed that long plate shape, block shape and suborbicular Sn phases were formed by mechanical agitation during the casting solidification process. The non-lamellar Sn-Bi Microstructure improves prominently the elongation of Sn-Bi alloy. The elongation of semi-solid Sn-Bi alloy with suborbicular Sn phase is enhanced up to 37% compared with the elongation of lamellar eutectic Sn-Bi alloy prepared by conventional die casting. After the agigation above 130 °C, non-lamellar Sn-Bi eutectic structure is formed and lamellar Sn-Bi eutectic precipitates. When the agitating temperature was 135 °C, the elongation of semi-solid Sn-Bi alloy mixed with non-lamellar and lamellar Sn-Bi alloy microstructure is enhanced up to 24%.

Abstract: Hydrophilic Polyvinylidene fluoride (PVDF) flat ultrafiltration membranes were prepared by wet-spinning method. The influence of blending ratio ( the mass ratio of PVDF and PAA), polymer concentration on preparation of blending modified hydrophilic PVDF ultrafiltration membranes were investigated, the technical parameters of preparation of hydrophilic PVDF membranes were determined, and hydrophilic PVDF membranes were prepared. Then, hydrophilic PVDF membranes were characterized in terms of IR spectra, contact angle, scanning electron microscopy images, pure water flux and rejection. The results showed that hydrophilic ultrafiltration membrane could be prepared with PAA and PVDF blends, the hydrophilicity improved greatly, and it was better than traditional PVDF membrane.

Abstract: The overlapping mineral resources are always occupied by the various buildings and cannot be exploited anymore, so to determine their boundaries correctly is an important task for both local government and constructers. Based on “regulations about exploiting overlapping coal and keeping coal pillar for buildings, waters, railways and major tunnels”, the software is developed to calculate the overlapping mineral resources. Four main design steps about the software are illustrated, the main dialogue box of the software is introduced, which is composed of three part boxes. In the end Chaochuan industry square is selected as an example, variables are calculated by the software, and the protected boundaries are drawn in MapGis.

Abstract: It has become a huge challenge faced by concrete industry to complete the high efficiency and low cost transportation under constraint trucks and time. Based on establishment of ready mixed concrete dispatching mathematical model and aiming at dynamic change of orders, the paper presented a kind of ready mixed concrete dispatching method based on simulated annealing algorithm. It changes ready mixed concrete dispatching into a combined optimal problem constrained by many conditions and introduces idea of penalty function, and then utilize distance matrix and new searching algorithm to compute optimal path and optimal truck number. Computation example of ready mixed concrete dispatching center in some city verifies the feasibility and validity of the proposed algorithm.

Abstract: In this paper, the CSP (compact strip production) technology was studied with the aid of elastic-plastic and thermal-mechanical coupled FEM using commercial software ABAQUS. The distribution and change of temperature, stress and strain field in rolling process were analyzed. In the view of boundary conditional influence on temperature, some factors such as thermal exchange between the work-roll and the thin slab, plastic deforming quantity of heat, cooling flux, convection and radiation heat exchange were considered during simulation. The results show contact heat conduction and deformation heat are the main factors that influence the temperature change of the thin slab. A good agreement was found between the predicted and the experimental data.

Abstract: In order to improve the engine room monitoring level of aging ship in coastal waters, to reduce engineers’ work load and to improve the supervision of shipping companies, the present study designs an engine room monitoring system by using VC++ programming technique, SQL Sever database technology, CAN Bus and CDMA 2000 network. The system incorporates such functions as data collection, data storage, interface display and operation, as well as wireless transmission, etc. Application results show that the system is stable, easy to use and incurs a low modifying cost. It facilitates both engineers’ timely control of the engine room status and shipping companies’ uniform supervision of the vessel. Thus the efficiency is improved and ship’s safe navigation is ensured.

Abstract: Airborne laser underwater detecting system is applied in military and civil field. The range gated technology can improve the SNR of laser detecting system efficiently and increase the detecting distance and scope. In this paper, the principle of range gated imaging was expatiated firstly, and then the demands and choice for laser transmitter and receiver were analyzed in detail. The Laser range gated synchronization control system based on TMS320DM642 was designed and the design principle and the practical realization process were implemented. This system can input target distance in real-time and choose the pulse width and delay time easily to gain clear range gated images.

Abstract: It is of vital importance to evaluate logistics performance of logistics company along with fiercer competition. ID3 algorithm is an effective method. In this paper, fisrtly we introduce ID3 algorithm. Then we apply it to evaluate logistics performance of a logistics company.

Abstract: Chinese fir (Cunninghamia Lanceolata) is a unique fast growing merchantable timber species in China with good materials, and is a major fast growing timber species in provinces of southern China. With the increase in Chinese fir plantation areas and the improvement in the degree of pure forests, the diseases of Chinese fir are increasing and their damages are getting worse, which have caused great losses and affected the sustainable, rapid and healthy development of forestry in China. This article gives a description of pathogenies, symptoms and occurrence regularities of four important diseases of Chinese fir, including Glomerella cingulata, Pestalotia Sp., Pseudomonas cunninghamiae and Chlorosis, and puts forward the corresponding control measures of these diseases, which provides an important basis for disease control of Chinese fir plantations.