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A nanoSiO2/polyacrylamide (PAM) organic–inorganic nanocomposite system was prepared using acrylamide as the monomer, nanoSiO2 as the modifier, and ammonium persulfate as the initiator. The system was then used to investigate the impact of various factors, including amount of modifier and concentration of monomer, thereby determining the conditions for optimal reaction. Infrared spectroscopy was then used for structural characterization. Measurements using the viscosity method indicated that the viscosity average molecular weight of the product exceeded 1 million. Electron microscopy images showed that a good organic coating layer formed on the surface of the microspheres.

In order to clarify the relationship between fractures and gas accumulation, using data of cores, image logs and experimental analysis, we analyzed the fracture genetic types, development characteristics, controlling factors, distribution rules and formation periods. And then, by combining the evolution of source rock, activity periods of gas source faults and the evolution of cap rock sealing ability in the study area, we discussed the relationship between tectonic fractures and gas accumulation. The results show that there exist primary fracture and secondary fracture in the volcanic rocks of Yingcheng Formation in Songliao Basin. Between the two types, the secondary facture is dominant. Tectonic fractures are controlled by lithology, lithofacies and faults in the plane, and by unconformities vertically, with the characteristics of distribution of cycles. The tectonic fractures formed in three phases, wherein the second period coincides with the hydrocarbon generation peak period. During the second period, gas source faults are active and cap rock had a better sealing ability. This period is the main hydrocarbon accumulation stage in the study area.

In this paper, design of roadway with stope working face Yeqing 8459 had been optimized combined with geological characteristics of the working face based on the actual measurement of ground stress and mechanical properties of coal rock of Yangquhe mine in Feng Feng mining area. Analyzing eight kinds of roadway support design scheme through numerical simulation and evaluating the supporting effect of each supporting design scheme, designating the construction guidelines ultimately.

Using the data of cores, outcrops, thin sections and image logs, we analyzed the fracture distribution characteristics in the ultra-low permeability reservoirs of Anpeng oilfield. Then, we analyzed the main factors controlling the development of fractures. There are tectonic fractures and diagenetic fractures in the ultra-low permeability reservoirs. Tectonic fractures with high dip-angle are the main fracture type. Under the stresses resulting from horizontal tectonic compressions in the Early and Late Himalayan movements, three sets of tectonic fractures formed in the study area, i.e. E-W, NE-SW and NW-SE orientations. The E-W oriented fractures are developed better, then the NE-SW and NW-SE oriented fractures. The formation and distribution of these tectonic fractures are controlled by the tectonic stress field, lithology, porosity, permeability, layer thickness and structures. Under the same controlling factors, the origin types, occurrences and development characteristics of fractures in shallow-to mid-depth reservoirs are similar to that in the deep reservoirs. But fractures developed better in the deep reservoirs than that in the shallow-to mid-depth reservoirs.

Fracture is an important controlling factor for the distribution of natural gas reservoirs in the tight conglomerate reservoirs in the Lower Jurassic Zhenzhuchong Formation at the north of Western Sichuan basin. Using the data of outcrops, cores, image logs and thin sections, combined with experimental analysis, we analyze the fracture origin types, distribution characteristics and formation sequences. There are three types of fractures, i.e. tectonic fractures, diagenetic fractures and original fractures in the tight conglomerate reservoirs. Among them, tectonic fractures are dominant, which can be classified into four sets, i.e. E-W, nearly S-W, NWW-SEE, NEE-SWW orientations. According to the statistics of areal density and fractal dimension, the average fracture areal density is 0.31cm/cm2, with the bulk in the range of 0.15-0.60cm/cm2. The fracture fractal dimensions are distributed at 0.95-1.70. There is a well positive correlation between fracture areal density and fractal dimension. Micro-fractures are important channels that connect matrix intergranular pores and intragranular dissolved pores, which improve the connectivity among pores. The tectonic fractures in the study area were formed in two periods, i.e. the end of Cretaceous and the end of Neogene.

This paper study the problem of the stability analysis for Lurie type systems with time-varying delay. By exploiting a suitable Lyapunov-Krasovskii functional, new criteria on delay-dependent stability are derived. Some better results are obtained by using a delay partitioning approach and reciprocally convex technique. Finally, numerical examples are presented to illustrate the effectiveness and reduced conservatism of the obtain results.

This paper selects the waste plastics of two typical electronic components of the computer circuit board, which are parallel communication port and slot, the influences of different heating rates and components on the pyrolysis and their kinetics analysis are researched. Pyrolysis experiments are performed under a nitrogen atmosphere, the experimental temperature ranges from room temperature to 1000°C, and heating rates are 10°C / min and 20°C / min. The result shows that the plastics of parallel communication port and slot in the weight loss have similar variation trend, and with the changing of heating rates, the temperature that reach the maximum pyrolysis rates also change. The weight loss rate of slot is lower than the parallel communication port. The pyrolysis rates increase with the increasing of the heating rates, the remainder mass fraction of the same samples are basically the same under different heating rate.

The accident happens sometimes in the oil industry and that the Human errors (HEs) are studied and used in the petroleum field is fewer. Then, the paper analyzes the early achievements and finds that most of the studies are aimed at the operation behavior but not the operator. So, using probability theory, the paper discusses the HE Causes and the relationship between human behavior and the accident, and it presents the error state evaluation model of organization and the evaluation model of the number of operators doing Error. According to the evaluation models, the management can get the risk status of accident of an organization.

Esterification of carboxylic acids and transesterification of β-ketoesters with alcohols have been developed by using catalytic amount ofp-toluene sulfonic acid (PTSA) to afford the corresponding esters in good yields.

During running period of the Three Gorges reservoir ,failure mechanism of bank slope is one of the important scientific problems of geological disaster mitigation for reservoir bank. GongJiafang bank slope is located in left of Wu Gorge in Three Gorges of the Yangtze River, where damage events appeared in 175 m experimental water storage in 2008 and 175 m normal water storage in 2011.Study shows that, GongJiafang bank slope located in the core of the Heng Shi stream anticline developes two group of tectonic fractures .The first one is unloading fracture of bank slope, whose upper part is in transfixion or intermittent transfixion status,and the second one belongs to shear shear fracture. Bank slope presents cataclastic rock mass structure ,whose water physical properties are poor. The shear strength parameters of bank slope soil reduce after being immersed, a decreas of about 52 % on cohesion, and 30 % on friction. Regional new tectonic stress field control the macroscopic law for failure of GongJiafang bank slope .Especially max2 shear zone in new tectonic stress field is consistent with the first group fracture, which strengthen progress of the unloading fracture developement .Bank slope basically appear unstable failure along with the first group fracture. About 50% unbroken lower part of unloading fracture in GongJiafang bank slope locate in reservoir water level change belt between 145m and 175m.During the reservoir water level rising, stability coefficient of bank slope decreases from 1.31 to 0.88 after being immersed, and it is inevitable for bank slope to fail suddenly. Research results for further exploration on the formation mechanism of bank landslide in the Three Gorges reservoir and its mitigation has positive significance.

In this paper, a method of magnetoelectricity power generation system for vehicle on the downhill of expressways is proposed. This system is a clean energy system that can be reused. Its structure includes car magnetic poles, magnetic poles imbedded in road surface, closed circuit imbedded in road surface, rectifier, inverter and storage battery. Multi-unit magnetic poles and closed circuits imbedded in the road surface are used in this invention, so when the car poles move with the running down of cars on downhill, magnetic flow in closed circuits will change to produce a technique of group control power generation. From the simulated system in the test, it can be seen that it is efficient and effective in generating power.

Regulated DC-DC converter and unregulated DC-DC transformer is the basic types of DC-DC converter. Now the research is focusing on the regulated form named regulated LLC resonant DC-DC converter. Unregulated form of LLC resonant DC-DC converter named LLC resonant DC-DC transformer is studied in this paper in order to increase the practical topology of soft-switching and high-efficiency DC-DC transformer. Design method is proposed by the gain curve analyze of LLC resonant DC-DC transformer, and load characteristic of gain and efficiency of the DC-DC transformer is analyzed specializing for optimal design. A LLC resonant DC-DC transformer prototype is designed and implemented. Experimental results verify the correctness and validity of the design method and the load characteristic analysis.

Adsorption isotherms of new type cationic Gemini surfactant named CGS on quartz sand has been got by using solution concentration difference method. The effect of different factors on adsorption, such as temperature, pH value and salinity, are studied too. The adsorption isotherm of CGS on quartz sand accorded with Langmuir shape. The adsorption quantity increased with the increasing of surfactant concentration at an adagio rate, then the adsorption quantity increased fast, and it reached adsorption saturation when mass concentration was 150 mg/L, and saturated absorption was 6.3 mg/g. The adsorption quantity of CGS increased with the increasing of salt concentration. When heighten temperature and pH value, the adsorption quantity of CGS decreased.

A twin-screw extruder was used to carry out the ring opening graft polymerization of L-lactide onto cellulose through reactive extrusion process. Ionic liquid (1-butyl-3-methylimidazolium chloride) [Bmim]Cl and Sn(oct)2 were used as solvent and catalyst, respectively. FTIR, TGA and XRD were used to investigate the structure, thermal stability and crystalline behavior of the reaction products. The result showed a successful ring opening polymerization of L-lactide on cellulose. Furthermore, it showed a increased crystalline degree and thermal stability after being introduced the PLLA.

Monitoring the flow behaviour on the micro-scale is very important in many industrial and biochemical process, the multiphase coexistence in microchannel provide many attractive characteristics compared to a single-phase flow. The precise flow rate control and well-defined channel geometries make it possible for us to make detailed investigation on multiphase flow phenomena. This paper aims at the measurement of resistance distribution in the cross-section of a novel microchannel based on the Agilent measuring instruments. Experimental results verified the possibility of estimation on particle concentration in the solid-liquid two-phase flow by the measurement of resistance distribution in the microchannel.

It takes a long time to replenish energy for electric-bus by charging, while battery swap is an effective way with fast energy supplement ability. The process of electric-bus battery swap is complex, how to realize automatic, efficient and reliable battery swap is an urgent problem to be solved. This paper analyzed the electric-bus battery swap system, and then constructed the control model of battery swap according to state machine theory, finally developed a battery swap control system based on Quantum Platform framework. The battery swap control system has been applied to many electric-bus battery swap stations; it improves the station’s efficiency and reliability greatly, and provides a guarantee for the popularization and application of electric-bus.

Coal seam B1 has characteristics of soft, poor air permeability, high gas content and gas pressure, therefore, there's strong outburst danger in Liangbei Coal Mine. However, the gas control in the coal with lower strength and lower permeability is still in the exploration. Depth of coal roadway is 610-750m at 11 mining area. The roadway excavating speed is seriously influenced by gas outburst, so it brings unfavorable influence to the mine. Based on the principle of relieving gas pressure in the low permeability reservoir, the shortages of existing methods are analyzed for gas control and optimization measure for gas outburst prevention, i.e. "short, flat, long, subtraction, stay, support", put forward from the view of system engineering. With the new measure, drilling efficiency increase, borehole collapse decrease, single borehole drainage scope increase, the gas control meets the requirement and the coal side is easily to be controlled. After application of the optimization technique, the roadway excavating speed is increased from 45m to 70m every month in 11mining area, and the tight situation of excavation replacement is alleviated.

Seven concrete beams were constructed with normal reinforcement bars. Grooves were opened on the concrete cover of the tensile region in the concrete beams using different combinations of carbon fiber reinforced plastic (CFRP) and pre-stressed helical rib bar (HRB), CFRP and HRB pre-stressed at different levels were inserted into the grooves and filled with resin. Flexural experimental results indicated that the limit bearing capacity, rigidity, and crack resistance of the beams were strengthened significantly with near-surface mounted two pre-stressed HRB and one CFRP (BF1P2) bar, or near-surface mounted one pre-stressed HRB and two CFRP (BF2P1) bars, in which HRB was pre-stressed at 30%, 45%, and 60% of its limit strength, respectively. Compared with an un-strengthened beam, the crack loads of the BF1P2 beams increased by 86.70% and 133.33%, the yield loads by 32.25% and 72.04%, and the limit bearing capacities by 72.73% and 90%. The crack loads of the BF2P1 beams increased by 50% and 133.33%, the yield loads by 50.54% and 136.56%, and the limit bearing capacities by 72.20% and 173.60%. The BF1P2 beams had better reinforcing results compared to those of the BF2P1 beams. The beam strengthened with HRB pre-stressed at 45% of its limit strength was the best concrete beam.

In this paper, needle-shape insulation defect was made in XLPE cable samples. With high-voltage and high-frequency accelerated aging, water tree was formed inside XLPE layer. One group of the samples was injected siloxane catalyzed by isopropoxide for rejuvenation, and the breakdown voltage was significantly greater than new samples. Nano-inorganic particles were observed by scanning electron microscope (SEM) inside the breakdown channels of rejuvenated samples. The insulation enhancement mechanism is described in this paper based on the new discovery, that the insulating property of cables is enhanced by the nano-inorganic particles, because of its ability to inhibit the partial discharge damage inside the water tree channel.

Based on the analysis for seismic load and failure modes of pile foundation, this article adopts dynamic Winkler foundation beam model, and employs continuous distributional and independent spring and damper, instead of the dynamic resistance of the soil around the pile, and to explore interaction between pile and soil dynamic at horizontal load. In consideration of six kinds of boundary conditions combination, this paper proposes the solution method for displacement and internal force on pile. From analysis of cases, it finds that the effect of pile’s length on dynamic response can be negligible when pile slenderness ratio l/d>20, and the pile can be simplified into infinite long pile. Dynamic response of pile increases with the increase of stiffness ratio. When establish the control equations, influence of axial force can not be ignore. Otherwise, results will be small than the actual value.

AlN-ZrO2composites were prepared by hot pressed sintering with AlN particle (d≈2mm, d≈1.5mm and d≈1mm) and ZrO2powder as material. Its phase composition, thermal conductivity and sintering performance were investigated by XRD, SEM, EDS and performance testing. The results showed that AlN could be reserved in samples, and the thermal conductivity and the apparent porosity of the samples ascended with increase of the content of AlN, and the bending strength of the samples with same AlN particle occurred change according to V-shape with content of AlN increasing. Thereinto, the thermal conductivity of the samples with 1.5mm AlN was most excellent, amang samples with AlN particle of 2mm, 1.5mm and 1mm, and sintering performance of the samples with 1mm AlN was best. Particle interface of AlN and ZrO2was high concentration area of elements Ca and O, and was a structural loose crack area with CaAl12O19formed. The area is abominable for performances of AlN-ZrO2composites such as thermal conductivity, density and strength. It is more appropriate for preparation of AlN-ZrO2composites with AlN particle of 1.5mm and 1mm as materials.

Established the Fuzzy matter-element Model for Comprehensive Evaluation of the stability of coal mining subsidence. Analyzed each factor of the stability of coal mining subsidence, and constructed Fuzzy Comprehensive Evaluation of coal mining subsidence. With Fuzzy matter-element theory, make the stability of coal mining subsidence as matter element thing, Application of the things of the evaluation criteria and the fuzzy values to construct compound fuzzy matter element, and calculate the weights of each index with AHP, construct degree Evaluation Model with the concept of closeness, in order to achieve the stability evaluation of coal mining subsidence.

Rare earth (RE) ternary complexes of Eu0.5Ln0.5(NPPD)3×DPQ (HNPPD = 1-(naphthalen-2-yl)-3-phenylpropane-1, 3-dione; DPQ = Dipyridobenzoquinone; Ln3+= Nd3+, Er3+, Ce3+, Dy3+), Eu1-xYx(NPPD)3×DPQ and Eu1-xLux(NPPD)3×DPQ (x= 0.0, 0.1, 0.3, 0.5, 0.7, 0.9) were synthesized by the reaction of RECl3×6H2O with HNPPD and DPQ in stoichiometry. The UV-vis and fluorescence properties of the complexes were investigated. The experimental results show that the luminescence efficiency of Eu3+complexes was enhanced by doping some other lanthanide ions.

The support of surrounding rock under the condition of deep mining has significant challenges due to high stress and low rock strength environment. Using the method of strengthening broken rock, reinforcing support force and releasing the mine-induced stress, this study has pointed out the complementary support technology which is based on the support using bolt-wire-shotcrete and is combined with steel arched yielding support. For the purpose of permanent support, the complementary support technology could combine the each support element and adequately take advantage of load-caring capacity of surrounding rock. The monitoring data of Xiaokang coal mine, Muchengjian coal mine and Yangquhe coal mine indicate that, for the various geological conditions, complementary support system has provided powerful support force to resist large deformation of weak and broken surrounding rock. It is proved that this type of support technology could reduce the mine-induced stress as well and has economical significance.

Rehabilitation of existing structures with fiber reinforced plastics (FRP) has been growing in popularity because they offer superior performance in terms of resistance to corrosion and high stiffness-to-weight ratio. This paper presents strain coordination results of (two groups)6 reinforced concrete beams strengthened with different methods including near-surface mounted CFRP bar and helical rib rebar in order to investigate the strain coordination of CFRP bar or HR bar and steel rebar of RC beam. Because there is relative slipping between RC beam and bar, the strain of CFRP or HR bar and steel rebar of RC beam satisfies the quasi-plane-hypothesis, that is, the strain of longitudinal fiber that parallels to the neutral axis of plated beam within the scope of effective height (h0) of the cross section is in direct proportion to the distance from the fiber to the neutral axis, the strain of CFRP or HR and steel rebar satisfies the equation:εCH=βεsteel , the value of β is equal to 1.0～1.2 according to the test results.

Rehabilitation of existing structures with fiber reinforced plastics (FRP) has been growing in popularity because they offer superior performance in terms of resistance to corrosion and high stiffness-to-weight ratio. This paper presents strain coordination results of (two groups)15 reinforced concrete beams strengthened with different methods including external-bonded and near-surface mounted carbon FRP strip in order to investigate the strain coordination of CFRP and steel rebar of RC beam. Because there is relative slipping between RC beam and CFRP, the strain of CFRP and steel rebar of RC beam satisfies the quasi-plane-hypothesis, that is, the strain of longitudinal fiber that parallels to the neutral axis of plated beam within the scope of effective height (h0) of the cross section is in direct proportion to the distance from the fiber to the neutral axis, the strain of FRP and steel rebar satisfies the equation: , the value of is equal to 1.1~1.3 according to the test results.

In order to prepare nano-hydroxyapatite/poly(lactide) (n-HA/PLA) composite with good interfacial interaction, some groups which could bind with Ca ions in HA crystals need to be introduced onto PLA surface. Poly(α-methacrylic acid) (PMAA) was grafted on the PLA surfaces via photooxidization and subsequent UV induced polymerization. Suspension of PMAA-PLA microparticles with an average size as 133.1nm was prepared with solvent evaporation technique. Then utilizing the action of template manipulating of PMAA-PLA microparticles, n-HA/PLA composite were synthesized. Zeta potentials measurement and SEM indicated that there were good interfacial interactions between two phases of n-HA/PLA composite. The results of cell viability confirmed that n-HA/PLA composite possessed good cytocompatibility, so the n-HA/PLA composite scaffold obtained by electrospun technology might be used as bone tissue engineering scaffold.

A electrospinning process to prepare soft tissue engineering scaffold was introduced in this study. This kind of scaffold was composed with ultrathin fiber and characterized with high porosity, well-interconnected pores and high surface-to-volume ratio. Biodegradable polylaticacid (PLA) was used to spin the scaffold and the scaffold was evaluated in vitro by analysis the microscopic structure, porosity, mechanical property, especially cytocompatibility. The results indicated that the electrospun PLA scaffold showed good cytocompatibility and the tensile property of electrospun scaffold was similar to human’s soft tissue. It could be expected that the electrospun scaffold would be potential in soft tissue engineering or soft tissue repair.

In recent years, electrospinning process is gradually applied in producing tissue-engineering scaffold. In this study, we chose polylacticacid(PLA) and β-tertiary calcium phosphate(β-TCP) as raw materials to fabricate PLA/β-TCP biodegradable composite scaffold by electrospinning process. The characteristics of the scaffold and effect of the scaffolds to cell proliferation and cell adhesion was studied. Compare with pure PLA scaffold, blendingβ-TCP in the spinning process of the scaffold could improve the properties of the scaffold, especially the hydrophilicity and the proliferation and adhesion of cells, this means that the material is more potential to be used as tissue engineering scaffolds.

With the strategy thought of sustainable development, proceeding from materials used in sustainable design, to analysis the relationship between the selection of materials and the environment resources. To realize the purpose of making a harmony development of human and environment, using the source from design, we think about how to reduce the destruction to nature, to maintain a sustainable development in economic society.