Search

Commercial activated carbon has been activated with KOH in order to investigate the effect of textural characteristics on CO2storage behaviors. The KOH activation has significantly enhanced the textural properties of the adsorbents, as compared to the pristine sample. CO2adsorption tests on the activated carbons were measured at 298 K and pressures up to 5.0 MPa, and the Langmuir-Freundlich isotherm was used to fit the adsorption data. The CO2uptake for the resulting adsorbents was significantly higher than that of the starting adsorbent in the studied pressure range. To better understand the structures and their influences on the CO2uptake, fractal analysis was conducted for the adsorbents on the basis of Frenkel-Halsey-Hill (FHH) equation. Fractal dimensions (D1and D2) that calculated from N2adsorption data were discussed. The results showed that the two fractal dimensions have different influences on CO2adsorption capacity. There was a negative linear correlation between CO2maximum uptake and D1, while CO2adsorption capacity increased with fractal dimension D2increasing. Therefore, it was concluded that appropriate pore structure fractal dimension with narrower PSDs within the microporous range had higher CO2adsorption capacity for the adsorbents.

In this paper, TiC reinforced steel matrix surface composites were prepared by vacuum evaporative casting infiltration process and self-propagating high-temperature synthesis. The effect of original composition, binder types and original coating density on the hardness, wear resistance and microstructure of the coating were also studied. The results showed that the Ti and C content was 80% while added 3% PVA, by pressed at 200MPa pressure leading optimal coating quality. Meanwhile the average hardness was 62.5HRC and the wear rate was 22 % of high manganese steel.

The emergence of electricity transmission with farther transporting distance, extra-higher voltage and greater transporting power and the formation of the regional interconnected power grid have greatly increased the probability of blackout, this phenomenon has fully exposed the vulnerability of large-scale interconnected power systems. In this paper, Electrical betweenness based on load transfer coefficient is proposed to construct structural vulnerability assessment index. Meanwhile, it is verified that the method is rational and available by analysising the difference of the IEEE-39 system between three attack modes.

Using Ti (OC4H9)4 as the precursor,and GAC as carrier, making use of technology of hydrolyzation and natural assembling,TiO2/GAC composite material was preparated at the lower temperature.The characterization of obtained TiO2 /Coconut-Activated Carbon’scrystal structure and appearance by XRD and SEM.The adsorption capacity and photocatalytic performance on phenol were measured.Results show that TiO2/GAC surface was well-distributed and remains a little interspace.A nanocrystal TiO2 aerogel size is without 30nm.The sample shows lower adsorption compared to GAC.But photocatalytic efficiency was higher than GAC under the exposure of the sunlight or the violet.

TiO2photocatalytic technology was developed in the past two decades in air treatment because of good photocatalytic effect, non-toxic, chemical stability, low cost, reusable features, the effect use of solar energy. A new composite materials of visible light photocatalytic degradation of low concentration of volatile organic compounds were produced by use of combining the adsorbent with TiO2photocatalytic technology.The adsorbent can enrich concentrations of volatile organic compounds on the surface of the TiO2photocatalyst. In this paper,the mechanism of the combined adsorption-photocatalysis for the removal of volatile organic compounds and immobilization methods、principle、craft were reviewed.The characteristic of the immobilization methods was analysed.It laid the foundation for the optimizing of the immobilization methods and the improving of the photocatalytic efficiency.

Many researchers applied creepage to calculating creep force, and relation between creepage and creep force are very complex and it has been a major problem for solving rolling contact theory. The paper established the finite element model of wheel-rail rolling contact based on ALE method (Arbitrary Lagrange-Euler method) in ABAQUS, and research impact of lateral motion of wheelset on creepage of wheel-rail contact. Results show in the lateral movement value difference between their longitudinal creepage is small, and maximum error is less than 20%, there is more distinct change trend about lateral creepage in left contact area than one in right contact area, and spin creepage of left wheel drop down in 4mm lateral displacement.

The effect of different elements of the auxiliary material on the grinding performance was studied in this paper. Through the grinding experiment, the grinding performance of the abrasive tool can be obtained. It shows that the grinding rate decreased until its content reached to16% following with increasing the NaHCO3 content. And the abrasive removal rate reduced, while the grinding efficiency was lower than the abrasive tool without adding NaHCO3. When ZnO content was reached 3%, the grinding rate increased by 43.48% and the grinding efficiency was also improved; while continue to increase its content, the abrasive`s self-sharpening were reduced, which resulting the grinding rate declined. As the NBR (nitrile rubber) content increased, the grinding rate improved and while its content was 20%, the grinding rate increased by 45.93% and the abrasive removal rate reached to the lowest, but the grinding efficiency reduced more. While continue to add NBR, the grinding rate will decrease.

nanoTiO2 is one of the most important inorganic pigments in many different fields. The effect of sinter and thermoprint on film-forming properties of nanoTiO2 in screen printing were studied in this paper. Compared with sintering, Thermoprint uses high temperature and pressure to make nanoparticles more tight. By scanning electron microscopy (SEM), X-ray diffraction (XRD) and Coating Adhesion Test, the better film-formation properties of thermoprint are demonstrated.

PDLC films are very useful materials and can apply in flexible displays, intelligent switchable windows, information storage and adaptive optical devices. In this paper we focus on its color display characteristic in reflective display and firstly we fabricated PDLC films by polymerization induced phase separation method and measured its transmissivity and spectral reflection curves of the printing ink layer and PDLC covered color by X-Rite DTP41 Spectrophotometer. From the result, it demonstrates that PDLC films show different optical transmission properties in long and short wavelength.

It is important to build a scientific and effective indicator system for the assessment and management of regional ecological construction. A theme-based and network coupled framework provides a useful approach to solve some problems in establishing indicator systems, such as lack of systematic study on indicators connotation and non-transparent processes of indicators selection. Based on the ecological construction practice in Fujian province, China, this paper (1) analyzed the main challenges of the ecological construction,implementation and development processes, summarized the currently main themes for ecological construction, and built a theme-based indicators framework; (2) established indicators selection criteria matrix and alternative indicators matrix by using network analysis method; (3) built a multi-objective selection model considering the economic cost, social effect and ecological integrity by genetic algorithm to quantitatively select operational indicators of ecological construction. Our study will contribute to deeply understanding the connotation and improving the science and validity of the ecological indicators system for ecological construction assessment and management applications.

Distribution automation, since the last century 90's in China, has accumulated a lot of technology and management experience. At present, distribution automation has been to the large-scale application stage. In order to ensure distribution automation economic and practical, this paper proposes distribution automation technical development route based on the analysis of several typical technologies, and supplies the specific technical principles. At the same time, this paper also points out the difficulties of distribution automation development, and puts forward some corresponding technical measures should be taken. This paper proposes the technology roadmap which has been taken by State Grid Corporation of China (SGCC), and has been used into the technology standard of SGCC.

This paper presents the application of bidirectional communication technology of CATV in Electricity Consumption Information Collection System (ECICS), analyses the architecture of bidirectional communication technology and the communication technologies to improve the quality of service, describes the physical architecture, security architecture and system functions of ECICS based on CATV communication network .

Energy metering is an important part of the power system. As the most integrated communication standards of power system, IEC61850 has not completely cover the metering information yet. Based on the analysis of metering system in substation, this paper establishes a complete energy metering communication model with extended three logical nodes and new five logical nodes in accordance with the principle of IEC61850 data model extensions. An appropriate IEC61850 service model is also described. Especially the use of documents for freeze data communication transmission, chunks of frozen data index and upload issues is solved excellently.

With more and more wide application of distributed power generation system, it is necessary to explore its impact on the power grid. The first residential user of distributed photovoltaic power generation system in China has recently connected to the power grid. A series of experiments were carried out by State grid metering center to detect status of the residential users system. The testing method of distributed photovoltaic power generation system and the results of field test are briefly introduced in this paper. Through the analysis of the test results, the characteristics of photovoltaic power generation system are discussed, in order to carry out further research of measurement technology.

PAN-based carbon fibers (CFs) were oxidized in a static electrochemical oxidation process. The surface color and chemical composition were investigated by means of digital camera and XPS. The results showed that, with the increasing distance from anodic roller, the surface color of CFs changed and the degree of oxidation got weaker and weaker. A close correlation was found between its surface color and chemical properties. It indicates that the electrochemical oxidation performance of one kind of carbon fiber can be handily studied using static electrochemical oxidation process because we can get CFs of different degree of oxidation through one experiment.

The cyclic voltammograms (CVs) of polyacrylonitrile (PAN)-based carbon fibers (CFs) were measured in different electrolyte aqueous solutions, temperatures and concentrations. By analyzing the CVs, the mechanism of the anodic oxidation of PANbased CFs was investigated. The results show that the anodic oxidation of CFs is virtually the activated oxygen formed by oxygen evolution reaction of water reacts with the surface carbon of CFs. Although there are more activated oxygen formed in alkaline electrolytes, surface oxides of CFs are easier to be formed in acidic electrolytes. The higher temperature can make the oxygen evolution reaction of water and surface oxidation of CFs be easier and more violent. The variation in electrolyte concentration can affect intensity of the two reactions, whereas it does not affect the difficulty of the reactions.

The effect of molecular weight on the structure and properties of PAN precursor was studied by the combination of scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC), etc. With the molecular weight increasing, the grooves on the surface become deeper and rougher, the interlayer spacing and crystallite size increase, and the exothermic reaction occurred later. The strength and breaking extension of PAN precursors increase gradually with the molecular weight increasing. The effect of molecular weight is greater than the effect of surface defects on strength for PAN precursor of high molecular weight.

To introduce feature and microstructure of edge crack of rolled coil, character and distribution of transverse corner crack of continuous cast slab (hereafter referred to as transverse corner crack), trace out rolling process of defective continuous cast slab, transverse corner crack of slab causes edge crack of rolled coil, the corner inclusions of slab and rolling process are also significant factors. To give some suggestions to resolve two dimensional heat transfer and high cooling intensity about control of transverse corner cracks. Inclusions cause stress concentration to lead to edge cracks of coils. Edge cracks of coils are related to transverse corner cracks of slabs, but not an exact one-for-one relation. Tiny transverse corner cracks may be removed by scarfing or furnace. Uneven or low temperature of the edge of rolled piece cause uneven extension of edge metal to form “fold”, namely “edge filament”. By research and practice, the quality of slab has been substantially improved in Shougang Qiangang.

The fitting models of dynamic modulus of asphalt mixtures were studied in this paper. UTM dynamic modulus tests were adopted to determine the dynamic modulus of two asphalt (A, B) mixtures. Then, the WLF equation and Arrhenius formula, based on the time-temperature equivalence principle, were used to get the shift factors and master curves of asphalt mixtures. Combined with Sigmoidal model and CAM model, it was founded that the Arrhenius formula was more suitable to get the master curves of asphalt mixtures. What is more, the CAM model was more suitable to fit master curves of both asphalt mixtures.

Data extraction is an important issue in Deep web data integration. In order to extract the query results of the Deep Web, it is firstly required to locate the target data block correctly. Due to the html source code of web pages can be parsed as well structured DOM, we proposed an effective algorithm for discerning the common path based on hierarchical DOM. Based on the common path and our predefined regular expression, the target data of the Deep Web can be extracted effectively. The experimental results on real websites show that our proposed algorithm is highly effective.

The aim of this study is to evaluate the effect of boric acid as an additive for gelled electrolytes. Cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and an equivalent circuit analysis were employed to study the electrochemical performance of the gelled electrolyte with the addition of varying amounts of boric acid. Scanning electron microscope (SEM) was employed to observe the grid corrosion in corrosion test. For moderate contents of boric acid, the electrode capacity improved, as well as the oxygen evolution profermance. However, the adverse effects of boric acid were found to include increased electrical resistance, decreased hydrogen evolution overpotential and promote the corrosion of the grid. The experimental results indicates that the optimum content was 0.4wt.%.

The heat treatment technology of PAN based carbon felt used for sodium-sulfur battery was studied. The influence of different heat treatment technologies on element content of felt and the microstructure of graphitized felt was investigated by the element analysis, Raman spectroscopy. The relationship between element content and resistivity of felt was discussed. Results showed that the oxidation time was shorter, the oxygen content of the stabilized felt was lower, which resulted in higher carbon content of graphitized felt. Thus the higher degree of graphitization produced the more regular structure and the lower resistivity of the felt.

Directional solidification is one of the most important processes to purify the impurities in the metallurgical grade silicon. A lot of factors could influence the result of directional solidification. In this paper, we researched cooling water flow which could influence the result of directional solidification. We have studied three data of cooling water flow which influenced the results of the removal efficiency of the impurities. Experimental results showed that cooling water flow can influence the density of dislocations and twins in the ingot. The metal impurities of Al, Fe and Ca were concentrated in the middle of the silicon ingot mostly. It was inferred that the bigger cooling water flow was better to the efficiency of the purification in the experiment.

The local structure evolution of polyacrylonitrile (PAN) fibers during pre-oxidation and carbonization was studied using X-ray diffraction (XRD) and radial distribution function (RDF). The nearest inter-chains distance of PAN is 6.88 Å, which is close to the diameter of the “rigid rod” model proposed by Warner. The third neighbor distances of carbon fibers are greater than that of graphite, indicating the planar six-member rings are absent in the carbon fibers from 500 to 1250°C. The structure of fibers transforms from long-range order to long-range disorder during the pre-oxidation process, then transforms from short-range order to long-range order during the carbonization process.

The TiC/Fe steel matrix composites were prepared by gelcasting technology of selecting the appropriate gel system and additives, the reasonable technological parameters. The toluene and 2-hydroxyethyl methacrylate (HEMA) were as gel system, oleic acid as dispersant. The rheological property, curing process and performance of the body were analyzed. The results show that the monomer (HEMA) content of 4.6wt% and oleic acid to 2wt% which increased the solid content from 50 to 54vol.%. The relative density of green body is 59.6%, the intensity is 28MPa. After sintering, the complicated shape was prepared.

The steel matrix composites pressureless infiltration technology was studied in this paper. It is necessary to develop a reasonable process, select the appropriate gel system and additives, and prepare the complex shape of the large-size steel matrix composites by using gel-casting. For reactive melt infiltration technique, the porous skeleton was prepared by gelcasting preparation of the titanium powder and ceramic particles mixed, and the C-containing liquid metal infiltration of the porous skeleton. To improve the wettability between the molten metal and the ceramic phase, it is used for the process Ti-C in situ reaction to accelerate the impregnation process. Finally, the steel matrix composites with higher density were prepared.

Starting with the research of the mechanism of treating organic wastewater, this paper found out various factors affecting electrode reaction, generation of hydroxyl free radical and flocculation reaction and the conditions promoting reinforcement of reaction, then associating with the advantage features of cavitation and impinging stream technology for degrading wastewater, it developed the "cavitation and impinging stream microelectrolysis technology", designed a novel structure of cavitation and impinging stream microelectrolysis reactor. In the technique of treating high concentration organic wastewater using microelectrolysis method, the problems of passivation and hardening can be solved by using this reactor with the features of high efficiency, environmental protection, safety, and good economics etc.

The porous titanium alloys containing molybdenum elements have been prepared by gel-casting methods. The composite coatings with hydroxyapatite (HAP) and TiO2 were prepared on the precursor in this study. The microstructure was examined by scanning electron microscopy (SEM) and X-ray diffraction, and part of the coatings was examined by EDS to indicate the linear distribution of HAP and TiO2. The Solid content of gel-casting of water base can reacSubscript texth 35%，and porosity can reduce to 42% after sintering.

Waste appliances have become new urban polluter because of the replacing of appliances households and corporates throw away. A case of recycling system of waste appliances in China is on the agenda. As the recycling system process, the layout optimization problem come out, we present a solution by using a new algorithm named Election campaign algorithm (ECA). ECA acts by simulating the behavior that the election candidates pursue the highest support in election campaign. Our comparative study indicates that ECA has good performance in this kind of optimization cases.

The equivalent conicity is the key indicators in the vehicles and multi-body dynamics simulation, and also in the vehicle's performance evaluation or acceptance testing. But it does not take into account the nonlinear contact influence, different reduction algorithms cause that technological exchanges and the vehicle's performance evaluation results are inconsistent and it is necessary to improve and simplify the description. Based on the overview of the parameters of the equivalent conicity, This article presents the contrast and comparative analysis of the two calculations of quasi-linear function of KLINGEL and the linear regression of the rolling radii difference function, also shows the influence of the contact nonlinearities on the wheel/rail contact geometry with the calculation of three CRH wheel/rail pairs(XP55,S1002CN and LMA) used the two methods, and also recommended that a unified algorithm should be adopted in order to lay a good foundation for engineering practice and theory research.

Using Poplar P-RC APMP as raw materials for culture paper making, the effect of conventional papermaking process and P-RC APMP fines-calcium carbonate co-flocculation process on the P-RC APMP culture paper properties were studied. The result showed that, comparing to the conventional papermaking process, co-flocculation process can supply paper with better strength properties, bulk and whiteness. When precipitated calcium carbonate (PCC) or ground calcium carbonate (GCC) were added respectively in conventional papermaking process, the PCC supplied handsheets with better bulk and whiteness, while GCC supplied handsheets with better strength properties. In the co-flocculation process, the effects of PCC and GCC were nearly the same in strength properties and bulk of handsheets, but PCC was more beneficial for whiteness. SEM images showed that PCC distributed more evenly in the fiber network, and well-bonded with fiber network. The particle size of GCC is relatively small, mainly filled in the fiber network and wrapped on the fiber.

This thesis introduces the basic principles and work methods of the pinhole camera detection technology. And the feasibility and veracity of pinhole camera detection technology are proved in the aspect of testing timberwork with an engineering project. And then according to the steps of determining the parameters, choosing an appropriate set of lens, choosing a suitable drill, drilling holes, removing the dust and debris and collecting data, the quality of the reinforced timberwork are confirmed to reach the standard after the processing and analyzing of the actual measured data The paper provide a new way for the quality check of the reinforced timberwork.

The principle of acoustic emission (AE) technology was introduced in this work, as well as the application and the achievements of AE in recent years, such as the utilization in unidirectional carbon fiber reinforced composite. References for in-depth research of material properties and failure mechanism were provided in this article.

The effect of different layers of glass cloth on carbon fiber reinforced hybrid composite core is studied in this work. Carbon fiber reinforced hybrid composite of different glass cloth content is made by pultrusion processing. Three point bending test and charpy impact test are taken to evaluate the toughness of different composite, and scanning electronic micro-scopy (SEM) and photograph are carried out to characterize the structure of different composite after destroyed. It is shown that, though at the cost of drop of tensile strength, the increase of glass cloth content in carbon fiber reinforced hybrid composite core improves the flexural strength and impact resistant, and does not affect the microscope destroy pattern and the microscopic structure of failure samples.

The large quantity of dyeing and printing wastewater, which contains high organics which can be hardly decomposed, is one of the main sources of water pollution. Based on summarizing the existing problems of traditional processing methods, the technology of cavitation jet and impinging streams were organically combined, which has great potential in wastewater treatment field, as a new method for degrading printing and dyeing wastewater, and then the “cavitation impinging streams (CIS)” concept was proposed, in which the superior features in wastewater degradation with CIS was expounded, and the problems to be further studied were pointed out.

Poplar P-RC APMP was chosen as raw materials for fines generation and collecting, and then the P-RC APMP fines and calcium carbonate were co-flocculated before they were added into fiber fraction to make fine paper. Effect of different sub-fractions P-RC APMP fines and dosage of fines to make fine paper were studied. The result showed that, with the increasing of different sub-fractions fines dosage, the whiteness of paper increased first then decreased. For 200-mesh fines, 300-mesh fines, 400-mesh fines, the highest whiteness are obtained at 10%, 15%, 10% dosage respectively. Adding fines has positive effect on strength properties of paper. With the increasing of fines dosage, the strength properties of paper increased. Besides, the order of paper whiteness and strength is 400-mesh >300-mesh >200-mesh when using the dosage is same.

The distribution of boron between solid silicon and melt Si-Al alloy (KB) and the interaction coefficients between aluminum and boron in solid silicon were investigated by establishing the equilibrium between Si–B alloy and aluminum at 1623 K ~ 1723 K for 4 h and then quenching them to obtain the content of boron and aluminum in silicon and Si-Al melt. The results shown that the distribution coefficients of boron KB are 0.139~0.325 (1623K), 0.332~0.587 (1673K), 0.684~0.956 (1723K), and the interaction coefficients are 32.8±2.34 (1623K), 16.3±1.17 (1673K) and 8.2±0.6 (1723K).

Energy consumption and greenhouse gas emission (GHG emission) from household consumption became increasingly important under the background of global urbanization. Taking Xiamen Island, a rapidly urbanizing area, as the case study area, this article categorized the settlement morphology of Xiamen Island into three types according to the key factors influencing the GHG emission of urban household consumption. The feedback loops intra- and inter-subsystems (settlement morphology, population, and carbon footprint) were induced by clarifying the causal relationship and feedback loops among variables. Then, the three subsystems were coupled based on feedback loops into the system dynamic model of carbon footprint of residential area in Xiamen Island and the validity of the model was verified. At last, the dynamic mechanism between the transition of settlement morphology and household consumption was characterized through the system dynamic simulation. The result proved that the model can dynamically characterized the effect of social and economic factors upon the household consumption carbon footprint, and is beneficial to the urban land planning of Xiamen Island and design and construction of residential settlement morphology.

Fe-Al2O3-TiC composite were fabricated by pressureless Ti-activated reactive melt infiltration. In this paper, a kind of Al2O3-Ti porous skeleton was prepared to be infiltrated with Fe-2Cr-3C alloy under vacuum. The microstructure and component analysis was investigated by scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD). Subsequently, the wear testing was conducted to investigate the wear resistance of the Fe-Al2O3-TiC composites. The result show that the Fe-2Cr-3C alloy melt can full infiltrate the two kinds of Al2O3-Ti porous skeleton at 1390°C for 2 h. In the Fe-Al2O3-TiC composite, the coarse Al2O3 particles was surrounded by the TiC layer, which was generated by the Ti-C in-situ reaction in the infiltration process. The abrasive wear resistance of Fe-Al2O3-TiC composite is better than that of the wear resistant cast iron commonly used in industry.

The high-temperature oxidation-resistant MoSi2 coating with B addition on Mo substrate was prepared by vacuum cladding. The structure and composition of the coating were investigated by SEM and EDS. The results indicate that good metallurgical bond between all coatings and substrate has been developed. Throughout cracks were avoided by the addition of B. Three multi-layer structures as MoSi2, Mo5SiB2, and Mo3Si were formed by diffusion from outside to inside. The thickness of Mo5SiB2 layer was reduced because of the decreased diffusion coefficient of silicon in MoSi2 with the addition of boron.

Magnesium-based alkalis and the Chelants (tetra acetyl ethylene diamine (TAED), Sodium Citrate and Opal) for hydrogen peroxide bleaching of bamboo pulp were investigated in this paper. The results showed that the optimal conditions of hydrogen peroxide bleaching of bamboo pulp were as follows: H2O2 4%, Mg(OH)2:NaOH=25%, Sodium Citrate 1%, Opal 1.5%, TAED:H2O2=0.67, temperature 60°C, and time 90 minutes. Under the optimum conditions, the brightness of bamboo pulp can be enhanced from 41.2% ISO to 78.2% ISO, while the brightness of bleached pulp by using the Mg(OH)2-based alkalis was higher than by using NaOH as the alkali source. It can be seen that Sodium Citrate, Opal, and TAED activated H2O2 bleaching needed lower reaction temperature, shorter time, and got better brightness and alleviated environment pollution, compared with the conventional H2O2 bleaching of the same pulp.

Bamboo, as a kind of non-wood raw material, has a long, thin fiber with wide distribution and rich abundance in China. It was studied that cooking reagents on bamboo pulping. AQ ramification and infiltration reagents were used to improve the cooking schedule. The results showed that AQ ramification could strengthen the cooking, but infiltration reagents couldn’t reach the good expect in cooking. When the AQ ramification and infiltration reagents were used together to cook, it could obviously decrease the Kappa number of the pulps and enhance the yield of pulps. Infiltration reagent Busperse 2806 was the best choice in cooking with AQ ramification. When the dosage of AQ ramification 0.05%, Infiltration reagent 0.03%, the yield of pulps increased 1.31%, kappa number decreased 4.0, and the dosage of AQ ramification 0.05%, Infiltration reagent 0.03%, the kappa number decreased 5.5, the screened yield decreased 1.54%.

The numerical simulation results of 12 typical fire scenarios prove that the boundary conditions of tunnel entrance exert a significant influence on the accuracy and reliability of the fire numerical simulation results in metro station. In the fire scenarios with four 400-metre-long tunnels at both ends of the platform, the fire numerical simulation result is the most accurate, but the total numerical calculation time is twice more than the other fire scenarios, due to the additional volume of the computational meshes of the 4 tunnels. In order to guarantee the accuracy and reliability of the fire numerical simulation results on the condition that the computational mesh volume and numerical calculation time have not to be increased, 18 new fire scenarios with the different width of the tunnel entrance have been designed to simulate fire smoke movement in metro station, and the results are inserted into Lagrange's Interpolation Equation, then the equivalent width coefficient ε of tunnel entrance is found to be in the range of 0.34～0.55. In consideration of the mesh cell size and evacuation safety, ε is suggested to be 0.375.

A particle reinforced hardface coating was prepared by vacuum cladding process. Firstly, titanium carbide composite powders were prepared by self-propagating high-temperature synthesis (SHS). The hardface coating was then formed on plain carbon steel substrate with the TiC composite powders and high chromium iron-based alloy powders by vacuum sintering. The microstructure of the coating was observed and then the wear resistance was studied. The results show that TiC composite particles uniformly distribute in the coating. The coating and the steel substrate are chemical bonded with each other. When the size of TiC particles is unchanged, with the increase of quality fraction of the TiC particles, the hardness increased gradually and the wear resistance of composite coating under different conditions changed. The unit area weigh loss increased following by the load increasing, and the unit area weigh loss is the most under Alkaline condition. And the unit area weight loss increased following by the increase of the abrasive and the reaction time.

Bamboo, as a kind of non-wood raw material, has a long, thin fiber with wide distribution and rich abundance in China. Its pulping properties are between softwood and hardwood. Adapting to the Chinese situation, developing bamboo pulp industrialization, according to the local conditions, is an available way to solve the shortage of fiber material for paper-making. Delignification of bamboo (Neosinocalamus) was carried out by conventional kraft and soda pulping under varying conditions to determine the relationships between selected cooking parameters (EA 14~20%, sulfidity 0~40%, maximum temperature 160 and 165°C, and time at maximum temperature 60~110 min) and pulp properties (kappa number and yield). Results indicated that in order to obtain relatively low kappa numbers(17~27), high sulfidity(20~40%) at lower EA(14~16%) increased pulp yield compared to the case of low sulfidity(0~10%) at higher EA(16~18%). Pulp with lower kappa numbers (13~15) and acceptable yield can be obtained at a sulfidity level of 20~30% with 18% EA or at a sulfidity level of 10~30% with 20% EA. Meanwhile, bamboo pulp in this condition not only helps to decrease kappa number in the subsequent oxygen delignification process, but also reduces the cost of chemicals in the bleaching process.

It is necessary to control hydraulic fracture height growth by creating artificial barrier for reservoir with thin payzone or weak overburdens and underburdens. In this paper, the influential factors on resistance role of artificial barrier were firstly identified and the parameters value range was determined. Then, an affixing intermediate container was combined into the core flow test device in order to ensure buoyant diverter well dispersed into carrying fluid in experiment test, and the particle size distribution of buoyant additives was tested by Malvern laser counter. The crack was made about 2/3 length in artificial core for simulating artificial barrier process by core flow test which were accomplished in base of recommendation practice of petroleum industry. Lastly, successive regression method was applied and a statistical relationship of the barrier strength with carrying fluid viscosity, floating additives concentration and core permeability. Then scouring experiments are made under modeling hydraulically fracturing treatment conditions. It was proven that the artificial barrier was steady at current treatment parameters and that could be effectively controlled hydraulic fracture height growth.

A natural ditch wetland grown with nature annual bluegrass (Poa annua L.), alligator weed (Alternanthera philoxeroides (Mart.) Griseb.), common duckweed (Lemna minor L.) and curly pondweed (Potamogeton crispus L.) etc. were selected to study the removal capacity of agricultural non-point source pollutants in the Maixi River in Guiyang City, the capital of Guizhou Province, China. The removal characteristics and seasonal variation of chemical oxygen demand (COD), total phosphorus (TP), ammonia-nitrogen (NH+4-N), and suspended solids (SS) in the ditch water was studied. The results showed that there existed a certain seasonal diversity in the removal characteristics of nitrogen, phosphorus and organic pollutants by the ditch. The removal efficiency of TP, COD and SS demonstrated an increasing tendency with their increasing concentration at the ditch inlet, whereas that of the NH4+-N displayed contrary tendency as the concentration of NH4+-N increased.

A layer of Ni-Cr-Si-B-Fe alloy was successfully coated on plain steel substrate by hot dipping process. The Ni-Cr-Si-B-Fe alloy coating has a homogeneous thickness of 3mm. The chemical composition and microstructure were studied with SEM and XRD in this paper. The result shows that the Ni-Cr-Si-B-Fe alloy coating is defect-free and chemical bonded with plain steel substrate. A light band zone of 8-10 m width is between Ni-Cr-Si-B-Fe alloy coating and plain steel substrate, and may be considered as a quickly solidified layer. The coating microstructure is a heterogeneous microstructure and changes from the light band zone to the surface of the coating, which is composed mainly of coarse columnar dendrite, needle-like precipitates and scattered eutectic structures. Four regions across the thickness of Ni brazing alloy coating, due to solidification conditions upon hot-dipping, have been identified with distinguished microstructure. In γ-(Fe, Ni) solid solution matrix, the hard phases of CrB, Fe2B and Cr23C6 is identified in the coating.

The nanosize magnetic particles were synthesized by thermal decomposition method with size distribution in the range of 10 ~ 30 nm. Different category and quantity of surfactants were used modifying the surface of the synthesized nanoparticles to control the particles’ shape and size. Multi-shapes, such as uniformity cubic, mixture of spherical and cubic, and the similar chick footmarks, were acquired in our experiment by different surfactants. It indicates the surfactant is a key factor for the size and shape of particles. The surfactants of PVP and oleylamine made the particle shape be uniformity cubic; However, the particle partly behaved as spherical shape in the case of using PVP and oleic acid as surfactants.

This paper establishes a 3-D localization model and based on this model, it proposes a collaborative localization framework. In this framework, node that observes the object sends its attitude information and the relative position of the object's projection in its camera to the cluster head. The cluster head adopts an algorithm proposed in this paper to select some nodes to participate localization. The localization algorithm is based on least square method. Because the localization framework is based on a 3-D model, the size of the object or other prerequisites is not necessary. At the end of this paper, a simulation is taken on the numbers of nodes selected to locate and the localization accuracy. The result implies that selecting 3~4 nodes is proper. The theoretical analysis and the simulation result also imply that a const computation time cost is paid in this framework with a high localization accuracy (in our simulation environment, a 0.01 meter error).