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Numerical simulation of cooling roller in planar flow melt spinning process was accomplished using CFD software, Get cooling water flow characteristics and the cooling roller wall temperature and pressure distribution with cooling roller rotation speed range 0-50r/s, The results show that: heat transfer coefficient h and Nusselt number between the cooling water and the inner wall surface of a copper roller creases with the increase of the cooling roller rotate speed, but the increase rate is relatively small; Effect of cooling roller rotate speed on inner wall pressure is large, cooling roller inner wall pressure increases with the rotation speed increase. This study provided a theoretical reference of amorphous cooling roller design and optimization.

The composite tubular scaffolds with highly oriented nanofibers used for vascular repair could improve the biomechanical properties of tubular scaffolds, satisfying the biomechanical requirement for the change of blood pressure and conducing to cell adhesion, migration and proliferation. The tubular scaffolds from poly(ε-caprolactone)(PCL) and silk fibroin (SF) composite nanofibers were successfully fabricated through electrospinning using cylindrical roller with an outer diameter (OD) of 3.0 mm. The influences of the collecting rotatation speeds on electrospun PCL/SF nanofibers orientation and radial/axial mechanical properties of the scaffolds were investigated. The results revealed that the electrospun PCL/SF tubular scaffolds fabricated at 1500 and 2000 r/min (linear velocity of 2.1, 2.8 m/s, respectively) possessed good arrangement around the circumferential direction of roller and sufficient radial strength and suture strength. The electrospun PCL/SF tubular scaffolds with circumferential-direction structure as a new vascular graft may be useful in vessel tissue engineering.

Using the mixed filling reaction column, this article examines that the influence of different inlet flow rate on the removal of nitrate nitrogen in groundwater, respectively by 90mL/h, 150 mL/h, 210mL/h velocity, under 30 °C each run five days, comparativly studies the influence of velocity on denitrification. The results show that the flow rate has an important effect on the denitrification of water, when the water inlet velocity decreased from 150mL/h to 90mL/h, the concentration of nitrate nitrogen reaction column effluent decreased gradually, and the denitrification of nitrite nitrogen accumulation system has been in a low level, but the ammonia nitrogen accumulation only in the flow rate of 90mL/h, began when the flow rate decreased significantly; also increased from 90mL/h to 210mL/h, the effluent nitrate nitrogen concentration, nitrite nitrogen concentration and ammonia nitrogen concentration increased significantly.

By zeolite column adsorption test process of nitrate pollution of groundwater, the research of three different inlet velocity of nitrate nitrogen removal, and the roles of nitrite nitrogen accumulation, zeolite adsorption of ammonia nitrogen and the influence of pH value changes, the results show that when the flow rate of 70 mL/h, the nitrate nitrogen concentration in the reaction column rising velocity under concentration less than before, but nitrate nitrogen concentration in the zeolite column has remained at about 3 mg/L, removal rate has remained at more than 95%; Nitrite nitrogen accumulation showed a trend of gradual decline, within the scope of flow rate of 90 mL/h, not affected by the late response, nitrite nitrogen concentration of 0.2 mg/L; As the reaction progresses, pH value gradually rose slightly, but still within the range of 6.0 to 8.0; Flow rate of 50 mL/h, zeolite adsorption of ammonia nitrogen effect is best.

This article introduces the working principle of the recovery fresh air heat pump units,and analyzes the applications system which units apply in air-conditioning heat recovery system.By using the principle of regression analysis of mathematical statistics,the article measured data for statistical analysis.The regression equation is established, the established regression equation has a high prediction accuracy.

A series of sulfonated poly(arylene ether sulfone) (SPAES) membranes were prepared for microbial fuel cell (MFC) application. The performance of the MFCs equipped with SPAES membranes was researched in details. The results showed that the output power density of the MFCs with different SPAES membranes increased with the increase of the IEC at the first few days. The performances were close after long-term operation. The influence of inoculum amount, the load and the concentration of K3Fe(CN)6 on the MFC performance was also investigated.

This paper focused on synthesizing the surfactant lyotropic liquid crystals (LLCs) through mixing the coconut diethanol amide (6501), primary alcobol ethoxylate (AEO9) and water. The LLCs phases formed in the ternary system are thoroughly investigated by polarized optical microscopy (POM). The obtained LLCs were characterized by XRD and SEM in order to analysis the texture, structure and the transformation. In addition, the LLCs have been applied in the preparation of TiO2nanoparticles in our research. The obtained TiO2powder were characterized by XRD and SEM, more importantly, the results showed that the LLCs are effective in the process of synthesizing TiO2nanoparticles.

The effect of enhanced solution treatment on microstructures, tensile properties, intergranular corrosion and exfoliation corrosion of a 6013 type aluminum alloy proceeded via various solution treatment were investigated by optical microscopy (OM), scanning electron microscopy (SEM), tension testing and corrosion resistance testing. The results show that compared with the conventional solution treatment (560°C×2 h), the enhanced solution treatment (560°C×2 h+570°C×2 h) can improve ultimate tensile strength and elongation, the corrosion resistance become worse after 151°C×8 h+191°C×8 h artificial aging. The tensile strength increase is believed to resulting from the coarse second phases dissolve. The corrosion resistance decrease is due to grain growth.

A novel substance, bi-(2, 4-dihydro-2H-3-(4-N-maleimido) phenyl-1, 3-benzoxazine) isopropane (BMIPBI), was investigated by density functional theory and calculation at the B3LYP/6-311+G* level for its molecular geometric configuration, infrared spectrum, electronic absorption spectrum and thermodynamic properties. The results demonstrated that, in the stable configuration of a BMIPBI molecule, the two side chains of 2, 4-dihydro-2H-3-(4-N-maleimido) phenyl-1, 3-benzoxazine connecting with both ends of the isopropane were not in the same plane, and the two side chains were rather different in structure. The minimal energy jump of gaseous molecules located at 533 nm, corresponding to π→π* jump of HOMO→LUMO. Along with the increase of the solvent’s polarity, the minimal energy absorption wavelength shifted to blue, mainly originated from changes in the transition properties, corresponding to π→π* jump of HOMO→LUMO+1. At 298.15 K and standard atmospheric pressure, the standard molar formation enthalpy and standard molar formation free energy of formation of the TMIPT molecule was-1212.46 and-532. 94 kJ/mol, respectively.

The prevention of urban floods and heat islands has become key emerging topics following recent climate changes. Pervious concrete can be used to effectively promote rainwater run-off into the ground, conserve base water, control floods, and regulate temperature. In addition, integrating and applying recycled aggregates, such as slag, in pervious concrete is an emerging development trend for enhancing the protection of environmental sustainability. In this study, we investigated various quality characteristics of pervious concrete. We adopted the design of experiment method as the research method, in which orthogonal arrays, factor response analysis, and analysis of variance were used to analyze data, and water-cement ratio, aggregate size, aggregate type, and cement paste filler ratio were the control factors. The analysis results obtained in this study can serve as a reference for pervious concrete proportioning designs.

In this paper, the fuzzy analytic hierarchy process (AHP) is used to establish the comprehensive evaluation index system for tiered electricity pricing scheme. First the calculation method of each factor is given, and it is translated into centesimal system. Than the fuzzy analytic hierarchy process (AHP) is used to calculate the weights of each factor. This evaluation method quantifies the qualitative indexes, to enhance the scientific and reliability for evaluation of tiered electricity pricing.

The crude oil of H oilfield contains wax and asphaltenes, and the formation water salinity is up to 160000-220000mg/l, so there is a tendency that the asphaltenes and scale will be deposited in the wellbore during the course of well production, which will influence the normal production greatly. It is necessary to make clear the sedimentary law and corresponding measures. The content of organic and inorganic of wellbore deposits of H oilfield is analyzed through a series of laboratory tests. On the base of the test results, integrated with comparison of conventional deposit prevention and removal technologies, chemical and mechanical methods are recommended. Moreover, formulation of the acid cleaning agent is determined and the principle and process of mechanical removal method is presented.

Planning of charging stations for electric vehicles (EVs) is the foundation of EV’s promotion and development. A novel multi-objective optimization model is proposed in this paper to better locate and size the charging stations for EVs from given alternative sites. Economic costs of charging station and the time wasted in waiting for charging are minimized in the model. The capacity constraints of the charging stations are included as main constraints. Pareto front is used to compare and estimate the practical value of the current substation locating and sizing plans. A calculation method based on rasterization and Voronoi diagram is proposed to make it clear where the jurisdiction of each charging station ends. Finally, the proposed model and calculation method are verified using case study.

Nanostructure WC composite coatings were prepared on surface of Q235 steel by argon arc cladding injection using microstructure WC feeding which were prepared by nanostructure WC powder. The microstructure of the coating were analyzed by scanning electron microscopy (SEM). Phase of the coating were analyzed by energy dispersive spectrometer and X-Ray diffract meter, moreover, microhardness and wear resistance were texted by Microhardness tester (HVST-1000) and friction wear testing machine (MMS-2A). The results show that the combination of coating and substrate is metallurgical bonding. and no Pores and cracks were founded in bonding area. aggregated nanostructure WC particles and nanostructure WC particles uniformly distributed in the coating. The maximum hardness of the coating is 1461 HV. Compared with the Q235 steel, the wear resistance of the coating increased about 15 times.

With the worsening ecological environment, urban landscape begins to focus on ecology theory in order to develop with balance. According to the current situation of the urban development, this paper, based on the theory of ecology, shows several ecological principles during urban landscape design process and then puts forward the evaluation system for urban landscape with intention for people to distinguish landscape quality. By analyzing urban landscape design based on ecology theory , it could be possible to realize the modern urban landscape meeting the needs of urban development and creating the harmony between human and nature.

Spatial layout optimization is a core of existing barracks renewal. Distinguishing from new built barracks, existing barrack spatial layout optimization needs to pay more attention to solve the contradiction between current and future. So in this chapter, we develop six primary design keys applied to existing barracks including harmony relations between barrack and its surrounding environment, emphasis on weakness construction, optimize allocation, improve security defense capabilities, enhance artistry of spatial layout and realize the whole structure optimization. Reference to ancient classical fortification thoughts and current construction conditions, we also explore 5 tactics to optimize existing barracks spatial layout , namely, function integration method, node co-ordinate method, axis control method, three-dimensional space construction method, as well as idle land reuse method. Finally, we choose one tipical case to integrated apply the above keys and tactics from theoretical and practical fields promoting the sustainable development of existing barrack .

The ancient building group of Jinci gathers different architectures in the dynasty of Song, Jin, Yuan, Ming, Qing , which is deserved to be recognized as the national treasure and living ancient architecture archives including more eras. Based on the location, layout, axis of the building arrangement, this essay expounds the layout features and analyses the ancients’ grasp of axis in Jinci.

Currently tourism, regeneration and reconstruction occur in the ancient city protection and gets hot, so protection of the ancient city becomes a research focus. This article regards the ancient city as a big ecosystem including old buildings, layout idea and cultural customs after analysis of a large number of cases. As people redefine the residency requirements, the original ecology of the ancient city has been difficult to meet the requirements of people in functionality, safety, convenience and other aspects. How to enhance the adaptability of the ancient city? For example, it needs to meet the requirements of modern society development, to adapt to the needs of modern people's lives, to adapt to the modern climate characteristics.

This study investigated the effects of silage additives on the anaerobic digestion performance of hybrid penisetum to produce methane. Specifically, we evaluated the effects of adding lactic acid bacteria (0, 1.0×105, 1.5×105, 2.0×105 cfu.g-1) and cellulase (0, 0.01, 0.02, 0.03 g.t-1) during ensilage for 45 days on biogas production of hybrid penisetum. The silage additives lactic acid bacteria (1.0×105cfu.g-1, 2.0×105cfu.g-1) and cellulase (0.03g.t-1) had a positive effect on the anaerobic fermentation performance of hybrid penisetum silage. The hybrid penisetum amended with 0.03 g.t-1 of cellulase showed the best biochemical methane potentials, with a methane yield of 218.15lN kg-1 ODMadded. The results of this study clearly demonstrate that type and concentration of additives influence biogas production by silage.

In the previous article we studied the strength quality of cement paste blended with waste solar PV cells. In this study, the similar research was performed by replacing cement paste with concrete except that a large w/c ratio of 0.55 was set since high permeability or more capillary pores may take a better observation on the experimental results. The conclusions were made on the effect of cement replacement with ground solar cells. The use of ground solar cells on the mechanical properties of cement-based composite was investigated, and as a result, we identified the strength performance for those of concrete specimens.

The fire resistance of concrete filled steel tubular column is usually obtained by the numerical analysis method, which is difficult to operate and not convenient in the actual civil engineering. So it is necessary to study the simplified calculation method. A large number of numerical simulation results of the temperature distribution of the section and the bearing capacity at high temperature of the concrete filled steel tubular columns are analyzed. The influences of secondary parameters are simplified. The simplified calculation method at 150 min and 180 min for the bearing capacity at high temperature of concrete filled steel tubular columns subjected to axial compression and fire is presented on the basis of comprehensive analysis of the numerical calculation results. The calculation results can be used as the basis to judge the fire resistance. It is shown by the comparison with the experimental results that the precision of the simplified calculation method can meet the requirements of engineering application.

Through the current situation survey of geological environmental disasters caused by limestone mining in Chongqing and combined with the principles of establishing evaluation index system and industry experts’ advices, we get the geological environmental impact assessment system of open-pit limestone mining which is consist of 7 dimensions and 25 indexes. Using analytic hierarchy process (AHP) to assign the weight of 25 indexes and based on membership functions of trapezoidal distribution to establish evaluation standard, the fuzzy comprehensive evaluation model is constructed. According to the principle of maximum membership degree, we get the influence degree of the geological environmental system affected by the open-pit limestone mining in Chongqing. This model makes the impact on geological environment of limestone mining quantitative and plays a certain guiding role in the local environmental protection strategy formulation and geological disaster prevention.

Ecological compensation is being applied to deal with transboundary external effects caused by water resources conservation or exploitation in China. A concept of water resources co-conservation and sharing was applied to burden the upstream conservation cost and to share the benefit in the whole river basin. Xin’an River Basin, related to two provinces in East China, was taken as the study area. The current territorial scales of the co-conservation area and the benefit sharing area were determined. The total actual water conservation cost for Xin’an River Basin was estimated to be about 488 million CNY in 2006. By analyzing the transformation of protection costs and benefits between different districts and sections, benefits brought by water to different beneficiaries were also estimated. The conservation cost was distributed to the water users or governments in the whole sharing area according to the proportion of shared benefits.

“Rapid response” features enable supercapacitor energy storage systems (SCESSs), used as auxiliary equipment for primary frequency regulation (PFR), to meet the stability and reliability requirements of power grids. In this application, capacity allocation for SCESSs is studied through theoretical derivation and simulation experiments. Firstly, the application scenarios of SCESSs in PFR are analyzed on the basis of weak grid frequency characteristics. Secondly, in two typical operating modes, namely virtual inertia control and droop control, an integrated operating mode is presented with consideration of the start-stop timing and the output depth of SCESSs, and the relationship between the operating modes and rated powers is derived. Then, to satisfy simulation needs of PFR, an analysis model for SCESSs is built, and a common process of SCESS capacity allocation is summarized. Finally, the optimal rated power, virtual inertia coefficient and droop coefficient of an SCESS is calculated with reference events and frequency control requirements of a weak grid as the benchmark. The results show that aforementioned theory is correct and reasonable, and that the proposed method can achieve optimal frequency regulation effects with a small capacity.

This paper introduces an easy automatic mousetrap. Solid works software is used for 3D model and structure design. When compared with existing products, this design has such advantages as simple structure, convenient and practical, easy to promote, simple principle, energy-saving and environmental protection, adaptability, high efficiency.

A numerical study was conducted to understand the flame characteristics of ethylene under O2/CO2 atmosphere by detailed chemical kinetic models. Special interest is focused on the effects of CO2 on flame propagation velocity and ignition delay. A modified reaction mechanism was established, and the ability of the reaction scheme was evaluated through comparison with well-defined laboratory data in the literature. A key result of the study is that the flame temperature and flame speed are significantly reduced because of the chemical and thermal effects of CO2. The most important reactions as well as the dominant reaction steps under both O2/CO2 atmosphere and air atmospheres were also studied. It can be concluded that although the main reaction paths of fuel oxidation under both atmospheres are quite similar, the most important elementary reactions are different from each other. Besides, the same reactions assume great importance for ignition under air atmosphere become less qualified under O2/CO2 atmosphere.

Themicro-grid technology is an effective way to promote renewable energydevelopment and utilization. Low voltage micro-grid can absorb photovoltaic,wind power and other large number of scattered random distributed power supply,and the system may be three-phase asymmetry while operation, randomness of thepower output and load is stronger. Therefore an improved bidirectional power flow algorithm is putforward suitable for low voltage micro-grid. According to the physicalstructure components of the micro-grid and different kinds of micro powersupply, the types of micro-grid in power flow calculation is studied to dealwith complex node in the micro-grid, improved Zbus algorithm is proposed tocalculate the power flow of micro -grid .IEEE-69 is taken as an example for simulation, the resultsshow that the proposed method is better for the biggest error ratio of voltagedrop and calculation time than traditional method. Atthe same time the algorithm is also suitable for island operation state of the microgrid.

In the background of condition-based maintenance (CBM), the equipment maintenance levels in a certain state have different choices, which has different impacts on the improvement of the equipment state and maintenance costs, which in turn affects the time schedule of equipment maintenance. Therefore, in this paper the equipment maintenance time and maintenance level are viewed as decision variables to make maintenance schedules. This paper presents a risk-based optimization model for system maintenance scheduling problem, considering the state of equipment, correlations of the equipment and the operation of grid. An optimization model minimizing total risk of grid operation by balancing system maintenance risk and failure risk is established, so that both optimal maintenance level and optimal maintenance time could be determined simultaneously. An example is taken to verify the validity of the model.

Aiming at the problem of multi point (32 and above) EFPI optical fiber gas sensing system in processing data, for instance, weak ability of parallel data processing, low computational efficiency, slow system response etc., this paper utilizing the advantage like maximum concurrent and distributed of membrane computing system studied a method of parallel data processing. This method adopted a algorithm called Bio-inspired Algorithm based on Membrane Computing-BIAMC compared to the commonly used Genetic Algorithm (GA) has less computational cost and higher computational efficiency. Firstly,4 Standard constrained functions was used as test and contrast function and then the improved algorithm is applied to the parallel data processing, to validate the quantitative analysis and effectiveness, in the end, through the simulation to verify the superiority of the algorithm in robustness and accuracy. The experimental results showed that with taking the parallel feature of data input into consideration the BIAMC which applying to EFPI optical fiber gas sensing system have improved the speed of data processing and the utilization rate of hardware system and the response time of whole system compared to the traditional serial processing method, which provided a new method of parallel data processing in multi-channel sensor system.

The micro-structural and formaldehyde adsorption abilities of pineapple leaf raw and degummed fibers are characterized by using SEM, FT-IR, chemical composition analysis and determination of acidic oxygen-containing functional groups and more other methods. Test results show that after being degummed, pineapple leaf fibers possess smoother surfaces, obvious grooves, better single-fiber separations and non-significant cross-sectional cavities. Hemicellulose’s characteristic absorption peaks disappear basically and their contents are reduced from 20.62% to 2.65%. The intensities of lignins’ characteristic absorption peaks drop and their contents are decreased from 3.68% to 1.20%. The locations of celluloses’ characteristic absorption peaks do not change too significantly and their contents are increased from 61.18% to 84.45%. The numbers of carboxyl, lactone and phenolic hydroxyl in acid oxygen-containing functional groups are reduced. Pineapple leaf raw fibers have higher formaldehyde adsorption abilities. After degumming, formaldehyde adsorption abilities of pineapple leaf fibers are similar, but all slightly lower than raw fibers.

DC-DC converter is a kind of power conversion equipment. Electricity is the direct power for most mechanical industrial equipment currently. However, because of the diversity of mechanical industrial equipment, electricity should be transformed through power conversion equipment. This paper presents a DC-DC boost converter with PWM control method. The hardware and the structure of the core circuit is designed and the boost principle is interpreted. The detail of the configuration circuit around is described as well.

Min-Max localization algorithm is usually used to acquire the position of a sensor node in wireless sensor networks by the reason of its simpleness and low complexity. However, Min-Max algorithm provides a coarse position estimation. In order to increase its accuracy, an Extended Min-Max (E-Min-Max) algorithm has been proposed. In this paper we focus on this algorithm and propose an improved E-Min-Max algorithm to enhance its accuracy further. Simulations show that the improved E-Min-Max algorithm outperforms its original version in localization.

To adapt to the changing requirement of task data interface under the situation of far distance, multiple segment, multiple circle, multiple satellite and multi-station visibility for satellite misson in transfer orbit segment, the web incremental maintenance system based on materialized view was achieved through applying incremental maintenance principle, database technology, synchronization mechanism and maintenance proxy, and realizing the synchronization and consistency of data interface about the distributed experiment information surveillance software system. The result shows that web incremental maintenance system can ensure the real-time and consistency of data processing and transmission.