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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.

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.

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.

Small-molecule fluorescent probe with advantages of small size, low background and simple preparation have been widely used. The detection of anions by small-molecule fluorescent probes is usually achieved through one of the following reaction mechanisms: hydrogen bonds and electrostatic interactions; metal or Lewis acid coordination; covalent interaction. This article summarizes the advances in the design principles of small-molecule fluorescent probes for the detection of anions in biological and environmental media in recent years.

Based on the V-type diesel engine crankshaft system, the paper combined the finite element method (fem) and multi-body dynamics method together, made a virtual simulation analysis. First, by 3d software and finite element software to establish the multi-body dynamic models of the crankshaft, bearing and piston, then simulated the actual engine working condition, and got the data such as crankshaft acceleration, velocity and displacement by the multi-body dynamics simulation analysis. By calculation, the paper found that by using the combination of finite element and multi-body simulation method, can we effectively simulate the diesel engine crankshaft dynamics characteristics.

A graphene nanosheet/polyaniline (GNS/PANI) nanocomposite was synthesized using in situ polymerization. The morphology and microstructure of GNS/PANI nanocomposite were examined by transition electron microscopy (TEM) and X-ray diffraction (XRD). Electrochemical properties were characterized by cyclic voltammetry (CV) and galvanostatic charge/discharge. GNS as a support material could provide more active sites for nucleation of PANI as well as excellent electron transfer path. The GNS was homogeneously coated on both surfaces with PANI, and a high specific capacitance of 331 F g-1was obtained at a current load of 0.02 A g-1. The kinetics properties of GNS/PANI electrodes were investigated by AC impedance measurements. GNS/PANI electrode exhibited higher electrochemical activity and more favorable kinetic properties during charge and discharge process.

In this paper, the computational fluid dynamics (CFD) methodology as well as the shear-stress transport (SST) k-omega turbulence model was adopted to model the air pressure reducer (APR). Changing the gas needle’s displacement of APR continuously, the writer obtains the displacement-pressure characteristics of APR. In order to demonstrate the validity of these characteristics, a physical experiment was conducted, which generates another displacement-pressure characteristic. Comparing the two characteristics with a good agreement, it is indicated that the CFD methodology is suitable to study the displacement-pressure characteristics of APR.

Three kinds of carbonaceous materials with different structural and chemical properties, Carbon Black (CB), Multi-walled Carbon Nanotubes (MWNTs), and Graphene Oxide (GO), were well suspended in sodium alginate (SA) solutions, and the suspension rheological behaviors were investigated in details. Steady rheological results showed that the suspensions exhibited same shear-thinning behaviors as SA solution. Dynamic rheological results showed that the complex viscosity (η*) was similar to that of steady rheological measurement, and both SA solution and SA/carbonaceous materials suspensions exhibited liquid-like behaviors, confirmed by the loss modulus larger than the storage modulus. The loss factor tanδremarkably decreased for SA/GO solution compared with SA/CB and SA/MWNTs suspension at the same concentration, indicating the increase of elasticity via interactions between the GO and SA.

Tianjin, the financial industry is constantly growing, the number of employees as well as financial institutions and financial assets grows rapidly. Financial agglomeration effect on economic growth can be reflected in: optimizing resource allocation, innovation-driven, industrial restructuring and so on. Tianjin promoted financial industry gathering in the financial markets, focusing on the development of multi-level marketing structure system, and gradually formed a diversified development and opening of Binhai New Area and adapted to modern financial service system.

In the process of calculating the crankshaft frequency and vibration mode, free mode is always applied for the crankshaft modal analysis. Considering the effect of centrifugal force generated by the rotation to the crankshaft frequency and vibration mode, the frequency and vibration mode of multi-speed cases are calculated, and compared, which fully shows the vibration situation of the crankshaft in the process of actual working situations, the results match actual situation.

The vertical distributions of nutriment elements (TN, TP and TOC) in the columnar sediments of sampling site in Lake Hong of Jiangxi were determined on the basis of 210pb dating.In order to investigate vertical distribution characteristics of nutrient elements and the sequence feature changes over time,analyze the impact of human activities on the Lake district environment.The method of 210pb dating was used to derive accumulation rates of 0.407g/cm2.a-1,The results showed that the contents of all the elements lowered continuously with the increase of the sediment depth.The historical profiles of Hong Lake showed that TOCTN and TP mainly enriched in 0-37cm ,and presented simultaneously changeable trends. 1862~1953, TN, TOC and TP are in a relatively stable trend, human activities in this stage have less disturbance to the environment and natural factors play a major role, Lake is without pollution to the state, belonging to II~IIIstandard, the overall ecological environment of lake is stable. 1953~1992, TN, TOC and TP are in the rapid increase stage,and the vertical variation of amplitude became enlarged.In this period, the increase of human activity,especially the agricultural activities,resulted in nutrient element content higher.Lake is being III ~ IV standard.The lake eco-environmental issues began to emerge. From 1992 to 2011, the nutrient content is with high volatility, human activities is the main factors affecting the lake environment, organic index and organic nitrogen pollution is IV level standard,the lake environment problem aggravate.

A green oxidation of benzylic alcohols to the corresponding aldehydes or ketones was achieved in aqueous media using ionic liquid/H2O2/HCl catalytic oxidation system. The procedure is mild, environment-friendly and simple. Ionic liquids can be successfully recovered and reused for the oxidation of the same (different) substance. The directing effect of the ionic liquid is supported by the good selectivities and yields. These reactions demonstrate the catalytic oxidation and phase transfer function of the ionic liquid is stronger than that without ionic liquid.

Honeycomb absorbing materials were measured using the method of free space in this paper. The reflectance of honeycomb absorbing materials was calculated and simulated, and it was verified based on the measured results. It was demonstrated that this test method was feasible. Through studying on absorbing properties of honeycomb, the results have showed that the radar absorbing properties of honeycomb are related to electromagnetic parameters, as well as thickness of the dip-coatings. With the increase of thickness of the dipping layer, the radar absorbing capability of high frequency and low frequency wave are significantly increased. It is worth noting that the resonance peak moved to the low frequency with the increase of dipping layer thickness. These results are useful for design of honeycomb absorbing materials.

Concerned that wind generators start up and establish the stable terminal voltage of the stator which is connected to the grid, this paper presents that wind generator can be operated as the independent generator at a certain voltage and frequency by means of capacitive excitation. The paper also deduces the calculation method for the proper capacitance value of self-exciting startup of wind generator. The paper builds a simulation model based on real time digital simulator (RTDS) and takes a case for simulating self-excited startup of wind generator. Simulation results demonstrate that the wind generator with self-excitation can successfully start up and be connected to the grid, it make a good agreement of actual situation. Furthermore, the results of RTDS simulation show that only proper capacitors value from optimized calculation can lead to a normal terminal voltage characteristic. The validity of proposal methods and designed simulation model is verified by experimental and computed results.

The Petlyuk distillation configuration has received considerable attention because of its efficiency to reduce the energy required for the separation of ternary mixtures. The dynamic properties of fully thermal coupling distillation column, which separates ternary mixtures of H2O, ethylene glycol (EG), diethylene glycol (DEG), are analyzed. The possible control configurations were investigated using Relative Gain Array (RGA) Analysis and dynamic simulation. The results indicate that the provided control scheme is able to produce a stable control response for thermally coupled distillation systems and shows better dynamic responses than the conventional distillation sequence.

In order to screen out the optimum varieties of sweet sorghum to be planted in Yellow River Delta, the agronomy characters of different varieties (strains) of sweet sorghum including jitianza 1 (JZ1), jitianza 2 (JZ2), jitianza 3 (JZ3), jitianza 4 (JZ4), liaosiza 1 (LSZ1), liaotian 1 (LT1), liaotian 3 (LT3), liaotian 6 (LT6) planted in the saline soil of Yellow River Delta were analyzed; Further more, the effect of different sowing time on the agronomy characters of sweet sorghum was explored with JZ2. The study provided bases for the cultivation of sweet sorghum in saline-alkali soil of Yellow River Delta in order to transform the biomass into bio-energy such as fuel alcohol.

Seedlings of sweet sorghum were supplied with 0.1 mmol L-1, 2 mmol L-1, 5 mmol L-1 and 10 mmol L-1 nitrogen fertilizers under 0% or 0.6% NaCl conditions. Then the growth parameters of the seedlings including photosynthetic gas exchange and leaf chlorophyll a fluorescence were determined. Results showed that the seedlings grew worse under 0.6% NaCl. Furthermore, with the increase of nitrogen level, the net photosynthetic rate (Pn), transpiration rate (Tr), the maximum photochemical efficiency of PSII (PHI(Po)) , the driving force on light absorption basis (D.F), the active reaction centers per cross section (RS/CSm), trapped energy per cross section (TRo/CSm) and PQ size of photosystem (PS) II (Sm) all increased and reached the peak at 5 mmol L-1 nitrogen level. On the other hand, heat dispassion per cross section (DIo/CSm) and the close extent of PS II reaction center (Vj and M0) all decreased with nitrogen level. The results indicated that the optimum nitrogen level for sweet sorghum is about 5 mmol L-1.

The paper introduces the theory of maximal wind energy tracking based on wind turbine aerodynamic theory, based on which methods to realize are provided and control subsystem is build on RTDS. Simulating results on RTDS, of whole DFIG wind generating system, showed the method is feasible and the control subsystem is correct and effective.

This paper introduces several kinds of reactors for methane catalytic combustion. Furthermore, we briefly summarize and compare advantages, disadvantages, research progresses and experimental applications of fixed-bed reactor, catalytic fluidized-bed reactor, catalytic reverse flow reactor, micro-channel reactor and catalytic membrane reactor for methane catalytic combustion.

Reactive power optimization is a typical high-dimensional, nonlinear, discontinuous problem. Traditional Genetic algorithm(GA) exists precocious phenomenon and is easy to be trapped in local minima. To overcome this shortcoming, this article will introduce cloud model into Adaptive Genetic Algorithm (AGA), adaptively adjust crossover and mutation probability according to the X-condition cloud generator to use the randomness and stable tendency of droplets in cloud model. The article proposes the cloud adaptive genetic algorithm(CAGA) ,according to the theory, which probability values have both stability and randomness, so, the algorithm have both rapidity and population diversity. Considering minimum network loss as the objective function, make the simulation in standard IEEE 14 node system. The results show that the improved CAGA can achieve a better global optimal solution compared with GA and AGA.

Superscript text Superscript textThe concentration of six potential carcinogenic compounds (3-Methylcholanthrene, Dibenz(a,h)acridine, Dibenz(a,i)acridine, Dibenzo(a,e)pyrene, Dibenzo(a,h)pyrene, Dibenzo(a,i)pyrene ) in the urban air of Dalian, China were monitored from November 2009 to March 2010 with active high-volume sampler. They were detected in gaseous phase and particulate phase, respectively. The total concentration of them was 563.2 pg m-3, and they were mainly found in particulate phase with the concentration of 540.5 pg m-3 while the concentration in the gas phase only was 22.7 pg m-3. The concentration of them changed apparently in different month.

In order to study the vary circumstance of underground water level of multi-level groundwater. This paper takes example for the Shenyang Eco-Tech Development Zone of Liaoning Province .Firstly, a conceptual model is built in this paper. Secondly, the groundwater system is numerically simulated and forecast with the internationally standard Visual Modflow. According the results of numerical simulation ，It is proved that between the underground water level’s calculating result and observation result has a higher fitting degree, and the results testify that the mathematical model established in this paper is reasonable. Conclusion the validated mathematical model can be used to simulation and forecast of the underground water level in the research area.

Supported rare earth double perovskite (La2MnNiO6) oxide catalysts were prepared by incipient wet impregnation method for methane catalytic combustion, and effects of the support (Al2O3, ZrO2 and MgO) were investigated. The loaded catalysts were characterized by means of XRD, TPR, SEM techniques and their catalytic activities were tested by complete methane oxidation. Depending on the different oxide carrier (e.g. Al2O3, MgO and ZrO2), catalysts have different catalytic properties, because the interaction of metal oxide-support will affect both redox property and dispersity of the active phase. The results on catalysts have shown that the dispersion on Al2O3 and MgO supports had an effect to enhance the catalytic performances of the catalysts that had been treated at 1100 oC. The activity of ZrO2 supported catalyst significantly decreases when calcination temperature at is 1100 oC. The dispersity of the active phase and the nature of the oxide carrier played an important role in the catalytic performance.

This paper reports NiO/γ-Al2O3 photocatalysts have well photocatalytic degradation capacity. NiO/γ-Al2O3 catalysts were prepared by Ni(NO3)2•6H2O,γ-Al2O3 with the impregnation method, and treated by the plasma-assisted, which were characterized by XRD, FT-IR,BET and other analytical tools. The influence factors of methyl orange degradation efficiency were analyzed under the 250W high-pressure mercury lamp.

Ba(Ti0.95Sn0.05)O3 ceramics were prepared using BaCO3, SnO2 and TiO2 et al as crude materials, La2O3 as dopant, and their dielectric properties are investigated. The morphology analysis of sintered samples was conducted by SEM. It is found that for 0.1 wt% La2O3 doped BTS5 ceramics sintered at 1290oC has the highest dielectric constant. It can also be seen that the samples sintered at 1260oC have higher dielectric loss, which can result from the existence of the pore. Meanwhile, in the terms of dielectric loss, 0.1 wt% La2O3 doped BTS5 ceramics has lower value and the dielectric loss is more stable with temperature varying.

When a rock sample is subjected to cyclic loadings, acoustic emission (AE) events increase sharply when the peak stress value applied previously is attained. This phenomenon is called Kaiser effect (KE). One important application of the KE is to determine the in situ stress, the knowledge of which is critical for the design work for underground engineering. Compared to the traditional methods, the acoustic emission (AE) method based on KE is done in the laboratory with special loadings on the rock cores and thus very economical. However, one fundamental question needs to be answered is the influence of the damage introduced by many factors during the period of the coring and samples preparation and so on. In this paper, we explore the influence by a series of loadings on samples in the direction perpendicular to the direction of the previous peak stress. Cyclic uniaxial compressions on the rectangular specimen and cyclic Brazilian tests were carried out based on the contact model in the particle flow code. The results demonstrate that, the disturbance in the orthogonal direction cannot influence Kaiser effect of the rock sample.

A sequencing batch reactor was employed to treat ammonia wastewater, the pH, DO and OUR were adopted to monitor the start of short-cut nitrification. The results showed that the start of short-cut nitrification was achieved in 31days, ammonia consumption rate was higher than 90% and nitrite accumulation rate was higher than 85%, when pH, DO and OUR were applied to monitor and determine the aeration time, under the condition of temperature was 30°C. With ammonia shock loading conditions, OUR curve couldn’t indicate the end of short-cut nitrification exactly. But real-time control using pH and DO could achieve a stable shortcut nitrification under steady stage and ammonia load shocking stage.

Electrical conductive carbon black-filled cement-based composites are significant as multifunctional structural materials. Double percolation in carbon black-filled cement-based composites involves both carbon black particle percolation and cement paste percolation, which has great effect on the resistivity of composites. Based on double percolation theory, the influences of sand-binder ratio and carbon black volume fraction on the resistivity of carbon black-filled cement-based composites are investigated. The results show that besides carbon black volume fraction, sand-binder ratio is a key factor affecting double percolation behavior in carbon black-filled cement-based composites. At a fixed carbon black content in overall mortar, with increasing sand-binder ratio, the cement paste percolation though aggregate phase increases due to high obstruction of aggregate but the carbon black particle percolation in cement paste decreases. This is because that the microstructure of aggregate is impenetrable so that the carbon black particles are limited in cement paste, that is, the carbon black content in paste is compacted and large amount of conductive paths are generated by lapped adjacent carbon black particles in paste. The double percolation in the electrical conduction in carbon black-filled cement-based composites is observed when the carbon black volume fraction is 7.5% and sand-binder ratio is 1.4, and its resistivity is only 3200 Ωcm, so that a sand-binder ratio of 1.4 and 7.5% carbon black volume fraction or more are recommended for attaining high conductivity with a compromise between workability and conductivity.

Based on the tunnel effect, a mathematic model was set up to describe the tunnel resistivity of carbon black-filled cement-based composites (CBCC). The relationships between the tunnel resistivity and the microstructure parameters, the motion parameters of carriers as well as the external electric field strength in the CBCC were established by using the model. Furthermore, the inherent relation between the tunnel resistivity and carbon black volume fraction was discovered. Moreover, the effect of carbon black volume fraction on tunnel effect of CBCC was investigated through experiments. The theoretical results obtained from the model were in agreement with the experimental data, which proved the rationality of the tunnel resistivity model of CBCC.

Based on the complexity of surface vibration of diesel engine, the wavelet denoising method is used to process the monitor signal Preliminary. And then several vibration modes are isolated based on EMD method. Finally take the energy of these vibration modes as the input parameters to create neural network for fault diagnosis of diesel engine valve. The method has accomplished the fault diagnosis of the diesel engine merging many methods.

Ba0.62Sr0.38TiO3 ceramics of perovskite structure are prepared by solid reaction method with the addition of x wt% NiO and their dielectric properties are investigated. It is found that Ni2+ can enter the B site in ABO3 perovskite when doping concentration is less than 0.6 wt%, whereafter, Ni2+ ions most segregates on the grain boundaries to inhabit the grain growth. Due to the decrease of grain size and the impurity, the dielectric constants are decreased. Decrease of dissipation factor is attributed to appearance of the oxygen vacancy and disappearance of the reduction of Ti4+ ion. It is concluded that the diffuse phase transition is linked to the adulteration of Ni2+. The disordering, mechanical stress in the grain and the oxygen vacancies are produced because of the adulteration of Ni2+, and the diffuse phase transition increases with the level of doping increasing, leading to that the peaks of dielectric constants becomes slower and flatter.

Spherical α-Fe2O3/Ag core/shell nanoparticles were prepared by reducing Ag(NH3)2+ with formaldehyde using the seeding method. 3- Aminopropyltriethoxysilane (APS) acts as a “bridge” to link between α-Fe2O3 core and Ag shell. The obtained nanoparticles were characterized by XRD, TEM, SEM, EDS, and Roman. The results show thatα-Fe2O3 cores are coated by Ag shell completely. The average size of α-Fe2O3/Ag nanoparticles is 95 nm and the thicknesses of Ag shell are 15nm in 3.7% HCHO and 1.0M AgNO3. The thickness of Ag shell can be tunable by changing reaction conditions, such as the concentration of AgNO3, reduction reaction rate. The surface-enhanced Raman scattering (SERS) effect of the core/shell particles are measured with Pyridine (Py) as molecule probe. SERS indicate that the Raman signals of Py adsorbed on α-Fe2O3/Ag nanoparticles exhibit large enhancement at 1010 and 1038 cm-1 respectively. And the intensity of signals is enhanced with the increase of the thickness of Ag shell. The uniform and rough surface of α-Fe2O3/Ag particles exhibits strong SERS activity in 3.7% HCHO and 1.0M AgNO3. The spherical α-Fe2O3/Ag core/shell nanoparticles exhibit SERS activity.

Mullite was synthesized by firing precursors prepared from kaolinite via a wet chemistry method at various temperatures. The acicular mullite grains were formed in samples with addition of AlF3 by this process. The phase evolution and morphology of the fired samples were investigated. For the samples without AlF3, the mullitization began to occur at 1300 and almost completed at 1550 , the grains formed were normal-shaped. For the samples with AlF3, acicular mullite was formed, and mullitization began to occur at 1100 and completed at 1250 . The growth of the acicular mullite was associated with a liquid phase. The formed acicular mullite was alumina-rich and had a composition of about 73.4 wt% Al2O3 and 26.6 wt% SiO2 (Al2O3/SiO2=1.65, molar ratio).

By means of the three-point bending impact equipment, with the measurement of ultrasonic velocity, the impact behavior and damage evolution of reactive powder concrete (RPC) with 0, 1%, 2% and 3% volume fraction of steel fiber were tested. The results showed that steel fiber significantly improved the compressive strength, flexural strength, flexural toughness and impact toughness of RPC matrix. The compressive strength, flexural strength, flexural toughness of RPC with 3% steel fiber increased by 40.1%, 102.1%, and 37.4 times than that of plain concrete, respectively, and simultaneously, the impact toughness of RPC with 3% steel fiber was 93.2 times higher than that with 1% steel fiber. RPC with 2% and 3% steel fiber dosage both had relatively high compressive strength, flexural strength and flexural toughness; however, compared with the sample with 2% steel fiber dosage, the impact toughness of RPC with 3% steel fiber dosage increased by more than 10 times. Therefore, taking economy and applicability into consideration, if we mainly emphasis on the compressive strength, flexural strength and flexural toughness, RPC with 2% steel fiber is optimal. While if impact toughness is critical, RPC with 3% steel fiber would be the best choice.

Core-shell nano-Al2O3-coated ZrO2 materials were prepared via a liquid co-deposition method using ZrO2 as cores. Surface of ZrO2 was modified by silane coupling agent. The mechanism of A-151[CH2=CH-Si-(OC2H5)3] was studied under the condition of HAc. The composite powders were characterized by FT-IR, TEM, EDS and SEM. TEM observation confirmed that amorphous Al2O3 layer deposited on the surface of ZrO2 and the thickness of the Al2O3 coating ranged from 5 to 10 nm. After sintered at 1650°C for 10 h, the size distribution narrowed down and the compactness of composite sintered body was better in comparison with pure zirconia.