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Coaxial nanocomposites were prepared by in–situ chemical polymerization of 4– dibromomethyl–2,5–2–octyloxy phenylene in the presence of multiwall carbon nanotubes. The morphology, microstructure and thermal and electrochemical properties of the resulting nanocomposites were investigated by scanning electron microscopy, Fournier infrared spectroscopy, thermal gravimetric analysis and cyclic voltammetry. The results indicated that the nanocomposites with uniform core-shell structure exhibited higher thermal stability than neat poly (phenylene vinylene). Furthermore, energy storage ability of these coaxial nanocomposites as electrode materials for supercapacitor was evaluated.

Jinma company of Liaohe oilfield has carried out weak gel flooding in-depth in block Hai1 and achieved good effect. But in the process of profile and flooding, problems of gelation fluctuating and gelling rate declining seriously affected the implementation effect of the profile control and flooding project. It is researched that one of main factors affecting gelling effect of profile and flooding system is the dissolved oxygen. Aiming at this problem, this paper studies critical value affecting gelling in combination with the actual situation of polymer displacement in block Hai 1. The experimental results show that, content of dissolved oxygen affects both gelling strength and gelling time of weak gel in the way that when dissolved oxygen content is between 0mg/L and 3mg/L, low gelling strength and long gelling time are obtained, while in the range of 4mg/L-10mg/L, gelling effect is good. Two critical values are respective 1.5mg/L and 7mg/L.

This paper mainly discusses the design and construction in coal enterprises management information system. Construction of coal enterprise information management systems follow the general information system construction process, first through needs analysis clearly the basic functions, the establishment of the system and the overall objectives and the establishment of basic principles; Second, obtain the logical solution based on detailed analysis of coal system, fully describe the existing system of business process and the required data; Finally, using the logic design of the whole system, and form the final software. In addition to this paper gives a detailed program of coal enterprise management, for the establishment of enterprise management information system has a certain guiding role.

The progressive failure study of the slope is a challenging problem. There exist a lot of problems at present in this area, it’s necessary to do some summaries. This paper did some analysis and discussion from four aspects: limit equilibrium analysis of the slope progressive failure; test analysis of the slope progressive failure, numerical simulation of the slope progressive failure and limit equilibrium analysis on the basis of finite element, and provided some reference for slope progressive failure study.

Calcium lignosulfonate (CL) was separated into three fractions with different molecular weight by using ultrafiltration membranes, and the effect of the composition of commercial CL on the setting time of Portland cement with anhydrite was studied in this paper. Results show that the CL fraction with the cut-off molecular weight of less than 150 (CL-A) shortens setting time most. Further analysis indicates that the content of reducing sugar in CL-A reaches to 15.3%, including mannose, glucose, galactose, xylose and arabinose, and these five kinds of monosaccharides are found to be the main components of inducing quick set of cement. Ultrafiltration is an effective method to remove most of the reducing sugar in CL and weaken the quick set of Portland cement with anhydrite.

The hydropower station tunnel construction is crossover operation and environment is poor. Installation space and time are limited. The paper introduces corresponding measures and installation method.Through field investigation and vast demonstration, using electric hoist and little bridge machine in equipment assembly area can avoid the effect to power house equipment installation and reduce crossover operation time. Using installation platform on the little bridge in hydro-generator area can reduce the use of the little bridge machine and improve the installation efficiency .

Light gauge steel-light weight aggregate concrete structure is a new type of structure system. This paper introduces the composition, characteristics and production and installation process of this kind of structure. For the Da Yunhe villas, as an example, this paper presents the structure detail and analysis method, and gives the bearing capacity and rigidity calculation result of the typical wall and floor beams, which verify the design code of the steel structure. This paper provides the beneficial reference and basis for future research and promotion.

Crack in the port crane which is prevalent in the metal structure of crane is a serious threat to the safety use of crane, therefore, it is very important to study on the production and repair of the cracks. This article takes the actual operating portal crane as an example to study on the crack locations and monitoring methods for metal structure of port crane, with the analysis for the reason of crane load bearing structure’s cracks ,this paper gives the common repair method for metal structure crack for cranes on this basis.

In this paper, we demonstrated the preparation and electrochemical performance of mesoporous carbon foams as electrode materials for ultracapacitors. By using n-octane as oil phase, cetyltrimethylammonium bromide (CTAB) and butanol as emulsifiers, resorcinol and formaldehyde dissolved in water as the aqueous phase, an O/W microemulsion system was obtained. Mesoporous carbon foams (MCFs) were prepared by the polymerization of the O/W microemulsion, followed by drying and carbonization and subsequently activation at 1273 K by KOH under nitrogen atmosphere. The mesoporous carbon foams were characterized by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analyzer. The results show that MCFs have specific surface area of 666.7 m2/g, total pore volume of 0.36 cm3/g and the most probable pore size of 4 nm. The electrochemical properties of the resultant mesoporous carbon foams have been investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge with a three-electrode system in electrolyte of 6 mol/L KOH solution. The CV curves show quite rectangular shape under the scan rate of 5-20 mV/s, suggesting a typical nonfaradic adsorption/desorption reaction. The mesoporous carbon foams possess linear galvanostatic discharge curves under the current densities of 10-50 mA/cm2 and corresponding specific capacitance values are 132.6-172.1 F/g. Thus the MCFs have good electrochemical performance and they provide an important candidate for electrode materials used in ultracapacitors.

Wave soldering is mainly used in electronic assembling process of traditional through-hole cartridge printed-circuit board and hybrid packaged process combining surface mounting with through-hole cartridge components. Compared with manual welding, wave soldering has advantages of high productive efficiency, good welding quality and high reliability. Wave soldering process is a complex and systematic project. During the practical productive process, flux coating quantity, preheat temperature of printed board, soldering temperature and time, uphill height of printed board and peak height should be strictly controlled and its process parameter should be comprehensively regulated in order to achieve better soldering quality.

To guarantee the quality of surface mounting electronic products, this article analyzes the process features of its four working zones, discusses some main factors which influences the soldering quality of reflow soldering, analyzes the common soldering defects and their causes according to the temperature and process features of reflow soldering during the process of reflow soldering like row-up, bridging, wicking and solder balling. By these measurements, appearance frequency of reflow soldering is effectively reduced and quality of surface mounting electronic products is also raised.

Take series of impact tests on welded joints for steel 09MnNiDR of LPG tank manufacture. And take scanning electron microscopy on impact fracture specimens. The results for the LPG storage tanks at low temperature welding process of steel making and the structure of low temperature storage tank to provide data to support safety analysis.

The stiffness and shear strength of soft clay attenuate under long-term cyclic loading, resulting in reduced foundation bearing capacity of road. The variation regularity of undrained shear strength of saturated soft clay which is normally consolidated or over consolidated under cyclic loading was studied with two-way vibration triaxial test, and some useful results are obtained.

Obtained stress distribution of hammer bottom according to the analysis of horizontal and vertical red sandstone fill dry density of the hammer bottom after dynamic compaction; affirmed the stress distribution situation of the hammer bottom through comparative analysis of the test results by laboratory and field monitoring.