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A corrosion-resistant and wear-resistant coating was prepared on the inner wall of copper tube by centrifugal self-propagating melting. The surface morphology, composition and phase composition of the ceramic lining FGM coating were analyzed by XRD and SEM, and the synthesis mechanism of the ceramic coating was studied. The results show that the functionally gradient coating is composed of three layers: ceramic inner layer, metal transition layer and copper substrate layer. The surface of ceramic lining is smooth and dense, which is mainly composed of Al2O3, CaF2 and a small amount of Fe Al spinel. The results show that the alumina phase is dendrite like and grows outward perpendicular to the tube wall, and the low melting point phase is evenly distributed in the dendrite gap, which effectively improves the density of the ceramic layer.

The inner-lined layers bonding strength of the ceramic-lined tubing was measured from 25°C to 600°C. The macroscopic structure and microscopic characteristics of the slippage surface of the ceramic-lined tubing were observed using optical microscopy and scanning electron microscopy. Combined with finite element analysis of the residual stress distribution at different temperatures, the shear failure model of the ceramic-lined tubing at different temperatures was given. The mechanical bonding force at the C-A (ceramic layer-alloy layer) interface is greater than the metallurgical bonding force at the A-T (alloy layer-base tubing) interface at low temperature, and the mechanical bonding force at the C-A interface is less than the metallurgical bonding force at the A-T interface at high temperature. The transition temperature is about 200 °C.

From the compression test of steel fiber recycled mortar porous brick masonry, it was researched the effects of different amounts of steel fiber and recycled fine aggregate on compressive strength, failure morphology, elastic modulus, stress-strain law and Poisson's ratio performance. The test value is compared with the calculation formula of ordinary mortar porous brick given in GB 50003-2011.The test showed that the steel fiber recycled mortar porous brick masonry had better compressive strength and deformability.

In order to improve the simulation accuracy of single hole nitroguanidine propellant extrusion molding process, the influence of wall slip on the extrusion process was studied. The finite element method was used to simulate the extrusion forming of single pore nitroguanidine. The power law constitutive equation considering the effect of wall slip was constructed to calculate the slip factor and non-Newtonian index , the influence of the slip coefficient on the pressure field, velocity field and shear velocity field in the flow channel were analyzed. compared with the actual results, the error of the middle aperture is 1.37%, the arc thickness error is 0.96% and the outer diameter error is 1.12%.Those errors are less then 1.5%. So, the simulation results basically meet the production needs.

Austenitic stainless steels widely used in cryogenic pressure vessel construction, and heads are formed by cold or warm spinning and stamping. Because of large deformation at excessive circular arc and at the straight parts of head during fabrication, the possibility of damage in these two positions during service is very high. In order to solve this problem, the commonly used S304408, S30403, S31608 steel plates processed under different temperature, different deflection and deformation rate were comparative studied. The evolution of the microstructure and mechanical properties were investigated to quantify the driving characteristics of the martensitic transformation by temperature and mechanical deformation. Consequently, the intergranular corrosion resistance of different microstructure was studied. The results of the research provide valuable reference for the selection and the processing technology of the head steel. Meanwhile, this study also provides a simple method for estimating the material properties after forming.

Groundwater is an important part of the human living space and supplies us with high-quality freshwater resources. However, the intrusion of any foreign matter into groundwater may cause groundwater pollution. Once this happens, clearing, control and remediation can be very difficult: not only does it need a lot of money, it is also technically challenging and time consuming. In view of current research on groundwater remediation in and out of China, we propose a package of groundwater pollution investigation, groundwater pollution remediation technology and groundwater pollution control processes with a view to providing theoretical reference for future groundwater pollution remediation efforts.

Shallow geothermal energy is a new renewable high-quality clean energy that has aroused great interest of man for its renewability, huge stock, cleanness and high availability. Encouraged by the favorable policies of the government, shallow geothermal energy exploitation in geologically suitable areas has become a great priority. In this paper, principal rock-soil physical parameters are derived from field thermal response test set in the context of Qing’an, Suihua City, and subsurface temperature field is modeled to further establish the heat exchange performance parameters with a view to providing reference for the planning and proper deployment of GSHP-based shallow geothermal energy exploitation in this area.

Gas emission happens after coal and gas outburst, and it could cause secondary disasters in the roadway. Therefore it is necessary to research gas concentration distribution law in the roadway after coal and gas outburst, and theoretical basis for avoiding the occurrence of secondary disasters could be provided. Based on the above, Fluent is used to simulate gas concentration distribution law in the roadway during outburst. The research results show that gas velocity of the initial stage is larger in the whole process of gas outburst and gas emission impacts opposite walls in the form of jet in the roadway intersection. The flow changes direction and moves along the main airway and return airway. It produces countercurrent along the main airway. Because the pressure in the main airway is high, gas migration velocity becomes zero after a certain distance and is "back" to return airway. The higher the outburst velocity is, the longer the flow length is. Gas concentration variation with two kinds of different outburst intensities and position are regressed and it shows that correlation coefficients of power function are the highest. The research results have a certain theoretical value to prevent the occurrence of secondary disasters after coal and gas outburst.

Various methods –direct methods, structure function methods and dimensional analysis-have been proposed to estimate the dissipate rate of turbulent kinetic energy. In this study these methods were appraised using LES data of a turbulent flow in the straight pipe at Re=5300. The fact that the corrected second-order structure function method is robust can be found. Note that when approaching to the wall at low Reynolds number, structure function methods and dimensional analysis method usually become inaccurate since they can not reflect information about the radial gradients. Direct computation methods now give acceptable trend and good estimation. Methods mentioned above lead to the same order of magnitude as values from DNS data most times.

Waste water is becoming more and more around us and phosphates exit everywhere in waste water. Eutrophication, the most common phenomenon caused by phosphate, can lead to water problems. Therefore, searching suitable materials to remove and control phosphate in waste water is of great significance. In this reach project, the method of adsorption was chosen to remove phosphate and two kinds of ceramic clay materials which were low cost and easily available as adsorbent for adsorption were used for phosphate removal. According to the removal efficiency of phosphate removal, temperature, solid to liquid ratio, the original concentration of phosphate and experiment time were studied in the experiments.

With the rapid development of power transmission and transformation projects in China, steel supporting structure has already became the most popular structural form for these structures. However, the limit of steel grade used for current substation supporting structures is normally Q420, compared with that of Q690 used in other countries. When the high-strength steel is used, the geometric parameters of section for members become smaller, and the stability of members is the most important factors to influence the bearing capacity of structures. The stability factor for axial loaded steel members in current 《Code for design of steel structures》(GB50017-2003) was derived based on the experimental results for steel members with lower steel grade, the results are inevitably different from those for high-strength steel members. To make the calculations of Q690 high-strength steel tubes more accurate and reasonable, this paper conducts experimental study on the bearing capacity of Q690 high-strength steel tubes under axial load to provide scientific basis for practical design of these structures.

Axisymmetric compression tests using Gleeble 3800 simulator were carried out to investigate hot deformation behaviors of an AA5083 alloy under high strain rate conditions. Sharp temperature rise and load cell ringing characterized by severely vibrational load responses were encountered at strain rates higher than 20 s-1 and sample buckling occurred at low temperatures. The load cell ringing was corrected using a moving average method with a two-way filtering operation to correct phase distortion. Isothermal flow curves were obtained by fitting the instantaneous temperatures into a binomial function, while buckling was correlated with sample height and Young’s modulus. After the corrections, hyperbolic sine equation was successfully used to extend from the hot tensile data having strain rates lower than 3 s-1 to 100 s-1. Quantitative analyses were accordingly made over the effects of temperature, strain rate and work hardening behavior on the flow curves. The previous constitutive equation in form of temperature, strain and strain rate was modified to predict the hot deformation resistance of the AA5083 alloy at temperatures of 250-450oC under the high strain rate operations.

A hybrid process coupling reverse osmosis (RO) with electrodeionization (EDI) was investigated to remove TDS and boron from simulated seawater in this study. The effects of applied total dissolved solids (TDS) and the concentration of boron in the feed water on product water quality were investigated. According to the results obtained, the TDS of the product water increased when a high applied TDS in the feed water; however, all of the TDS of the product were complying with relevant standards within experimental parameters. When the boron concentration was below 5.64mg/L in the feed water, the boron concentration of the product water was complying with relevant standards.

Contaminated soils in the environment remain being a significant issue during land application. Numerous methods have been suggested in recent years for remove, treating and beneficial uses of heavy metal-containing soils. In this research, the basic characteristics and the geochemistry of metals in the soils were studied, and which were subjected to percolation test. The results of experimental leaching tests of soils are subjected to model calculations. In addition, the separation processes, hydrocyclone treatment, is designed to separate coarse and fine-grained particles by high settling velocity of particles. The FLUENT flow simulations are help to demonstrate to liquid-solid flow and the simulation results are feedback to the hydrocyclone operation and design.

The aim of this study is to discuss the plastic shakedown and true stress of the cyclically loaded pressure vessel. A thin-walled cylinder pressure vessel is made according to actual working state and a water pressure test system is built. The vessel is loaded to different strain levels of plastic deformation first. Then it is loaded cyclically to shakedown state. The relationship between plastic strain and shakedown range is given based on numerous experiments. The constitutive model of the true stress-true strain of the vessel is obtained. The experimental results show that the ratcheting obviously occurred when the vessel is cyclically loaded to plastic deformation. The true stress-strain constitutive model which is presented in this paper can show appropriately the constitutive relation of the vessel when it is under multi-axial stress state. The application of uniaxial shakedown constitutive model has been demonstrated in this study.

Digitization is the inevitable trend of social development, in order to meet the requirements of social development, the apparel industry also called for the speeding up of digitization to improve the technological content of the garment industry. With visualization, virtual reality and other emerging computer technologies emerge and promotion, fashion design in terms of design, style and methods are subject to convey a profound impact. This paper analyzes the virtual reality technology in the field of fashion design developments and sumarize its developing trend in coming dacades.

A large number of cracks are found in the 1500m3Liquefied Light hydrocarbons vessel during the inspection after two years of running.In totally,six vessels being fully heated treated is made of 15MnNbR. Researchers used X-ray stress analyzer measured the welding residual stress of vessels that have been cracked and uncracked. The results show that, residual stress of uncracked spherical vessels are in good condition, while those value of cracked is high, the value of the highest is 1.05σs. It indicates that the possible reason for the separation is the residual stress in the high state. Through welding and heat treated for the second time, the welding residual stress decreased obviously. It indicates the impact of this measure is good.

Tests including the constant load tensile, three point bending and hydrogen induced cracking (HIC) are executed to evaluate the comprehensive properties of the 15CrMoR(H) with new smelting process in saturated hydrogen sulfide (H2S) according to NACE and National Standard. By analyzing and fitting the results of constant load tensile test, the stress-life mathematical model of this material is given. Results show that the stress corrosion threshold of the constant load tensile is 0.7Rel (252MPa).The nominal stress of three point bending SC is higher than 4.5 Rel (1620MPa). Results of HIC test show that the crack length rate CLR is 4.40%, the crack thickness rate CTR is 0.87% and the crack sensitive rate CSR is 0.04%. According to EFC standard, the safety margin is 3.4, 3.4 and 37.5 times respectively. All the experimental results show that the 15CrMoR(H) material has excellent H2S stress corrosion cracking resistance properties.

Shanxi Gardens play an important role in Chinese ancient gardens. This thesis aims to explore the development and space characteristics of the private gardens in Shanxi, analyze the factors behind the characteristics and call for the protection and study of the ancient gardens in Shanxi Province.

During the application of solid expandable tubular (SET) technology, the friction between expansion cone and tubular results in high expansion pressure, high operational risk, and severe abrasion of expansion cone over long distance operation. So far, traditional methods have not been able to effectively achieve the purpose of reducing the friction and improving the wear resistance of expansion cone. The bionic non-smooth surface has been studied and confirmed to have characters of reducing friction and wear, and these characteristics have been successfully applied in many fields. In this paper, the bionic non-smooth theory was applied on the surface of expansion cone, and bionic cone was fabricated by laser texturing and carbon based coating. The ground tests proved that the bionic surface treatment on the expansion cone could reduce the expansion pressure by 15% at least and improve the wear resistance.

This paper investigates the thermal profiles of plasma neutralization induced by microwave radiation by the chronological examination of their thermal distributions. Single triangular, circular, and bowtie-shaped copper tapes were trimmed to investigate the plasma neutralization burst under microwave irradiation. The infrared thermal images showed that the copper tape with a more acute angle and with a narrower gap between the bowtie-shaped electrodes was inclined to generate high plasma density. A high plasma-density area was eventually observed, generating a higher temperature peak based on the experimental results. Thermal dissipation under room temperature was found critical in determining peak temperature after burst. These results may provide basis for the development of an inexpensive, microwave-induced local heating.

The ethyl acetate extract was made from the leaves of Sindora glabra by solvent extract method and silica column chromatography, and was analyzed by means of gas chromatography-mass spectrometry. The results show that thirty-four peaks were observed, in which twenty-eight compounds were identified accounting for 93.40% of the total volatile substances detected. The major constituents are Hexadecanoic acid, ethyl ester (12.77%); (1.alpha,4a.alpha,8a.alpha) -7-methyl-4-methylene-1-isopropyl -,1,2,3,4,4a,5,6,8a-octahydro naphthalene (11.95%) and 1,2-Benzenedicarboxylic acid, butyl 2-ethylhexyl ester (11.10%). The main types of compounds are fatty acid esters (44.46%) and terpenoids (25.39%). And most of the terpenoids are sesquiterpenoids which accounted for 23.44% of the total composition.

This paper studies on the stability capacity of E-glass fiber reinforced polymer (GFRP) tubes under axial compression in order to get the formula, which can be applied to structure design. Firstly, on the basis of test data, finite element analysis is carried out and initial geometric imperfection is considered in the models. Then, it's proved that edge-failure criterion is suitable for stability analysis of GFRP slender components by comparison of results derived from several classic formulas. Finally, a modified Perry-Robertson stability formula is proposed so as to ascertain corresponding stability coefficients for GFRP tubes with different slenderness ratio.

The authors improve the performance of an image cipher algorithm based chaos theory. The authors do Preprocessing for the algorithm firstly, makes spatial scrambling based on image blocking in order to interrupt pixel position, then furthering this interruption through Arnold mapping, and transforms pixel RGB color space through optimized Arnold Mapping. At last, we get the final encrypted image through a series of iteration. With some theoretical analysis of security, this algorithm has a lot of advantages such as, good diffusion properties, its key space is safe enough to resist exhaustive-key-research attack, high effectiveness and resisting common attack successfully, but it needs improvements on some aspects, such as the key sensitivity.

The hot-dip coatings containing Zn-Al-Mg-Ce were prepared through congruent melting. The anti-corrosion performance of the coatings was researched using the weight loss rate by the neutral salt spray testing. The reasons of the effects of the elements Al, Mg, Ce on the anti-corrosion performance promoting were researched through the analysis of Scanning Electron Microscope and the polarization curves. The results showed that Al, Mg, Ce embedded in the Zn matrix uniformly and the protective effect for the steel was enhanced by the electrochemical action.

The hot-dip galvanizing coating can promote the anti-corrosion performance of the bolts in outdoor steel structure engineering. But the anti-corrosion performance cannot match that of the steel due to the centrifugal process. In this paper, the anti-corrosion performance of four kinds of bolts obtained from different company was researched by the neutral salt spray test method. The results show that the anti-corrosion performance of the all four bolts was unsatisfactory. The reasons were studied through testing the thickness of the coating, coating uniformity, surface morphology and elemental composition. The results show that the causes are the lower thickness of the hot-dip coatings, too much defects on the surface of the coatings and the elemental composition impurity.

in order to research the influence of bolt pretension on the rigid flange joints stiffness further, ANSYS finite element model was built on the basis of experimental investigations, and was used to research the influence of bolt pretension on the axial rigidity, shear rigidity and bending rigidity. The calculation results indicated that the axial rigidity, shear rigidity and bending rigidity were all increased along with the increase of bolt pretension, and the increase of axial rigidity was most obvious.

In the period of real time mechanical analysis and life style detection to the excavation tunnel equipment's cutter head, it is a necessity for the signals sensed by detection unit to be pretreatment processed. It closely concerns with the accuracy and validity of whole mechanical analysis results. By analyzing the features of all possible interference, this paper gives a study on signals initial processing applying method of digital filter and blind signal extraction. Simulation results show that the proposed scheme is effective enough to the mechanical analysis task.

The zinc-rich coating prevents steel from corrosion by sacrificing electrochemical cathode anode protection, but the zinc content is the most important parameter. In this paper, the zinc-rich coatings made with the amino resin, acrylic resin, complex solvents, auxiliary agents and high purity zinc powder. The coatings were applied onto steel substrate and then placed in neutral salt spray for 3000 h in order to study the anti-corrosion performance. The results showed that the anti-corrosion performance was promoted with the zinc content increasing. When the zinc content was higher than 86 wt. %, the anti-corrosion performance can be reached 3000 h. The anticorrosion mechanisms were studied by polarization curves and scanning electron microscope (SEM).

A new dual-bed photocatalytic hydrogen production reaction system is proposed in this paper. In this dual-bed system, one bed is photocatalytic hydrogen evolution reaction bed in which I- is oxidized into I2 by a hole and H+ is reduced to H2 by an electron, and the other is the hole-sacrificed agent regeneration bed in which I- is regenerated by reducing I2 with Cu2O. The two reaction beds are connected with two constant flow pumps to form a circulation loop. The hole-sacrificed agent I- can always be renewable by circulating the reaction solution between dual beds. The dual-bed reaction system achieves to produce hydrogen continuously, steadily and efficiently.

Portland cement, crushed stone, sand and superplasticizer were used to obtain a high strength concrete with a low water to binder ratio. A reticular polypropylene fiber and a single polypropylene fiber were used to improve the strength of the high strength concrete, but the effects of the two fibers on the slump and strengths were quite different. The reasons of the differences were the surface area and the modulus of elasticity of the fibers. The results show the reticular fiber was better to used in high strength concretes.

Portland cement, silica fume, superplasticizer and fly ash cemamsite were used to obtain a high strength lightweight aggregate concrete with lower water to binder ratio. An enhancement effect on the strength was gained by adding steel fiber. When the expansive agent added with the steel fiber a synergistic reinforcing effect on the compressive strength, tensile strength and bending strength was obtained because of more energy consumed to pull the fibers out under the different loads.

16MnR is the typical material of pressure equipment which worked under complex stress state in engineering application. In order to be close to the actual combined tension-shearing stress state and explore the relationship of deformation capacity and different stress state, many groups of combined tension-torsion tests on 16MnR specimens were designed and the equivalent stress-strain relation under different stress state was obtained. The concept of stress triaxiaty (TS value) was cited to characterize the different stress state and the result showed different stress states have a great influence on the material plastic deformation capacity, TS value turns larger, the plastic deformation weakened; 16MnR has a strongest plastic deformation capacity in pure torsion; the level of tensile stress had no significant effect on the maximum stress in the biaxial stress state, but has a significant inverse relationship with the maximum equivalent strain .At last, the mathematical relationship between maximum equivalent-strain and stress triaxiaty could be found. If the stress state of one point in the engineering structures is certain, the maximum equivalent-strain can be estimated.

Two novel low viscosity polyamide curing agents are prepared, the viscosity of the polyamide-1 synthesized from adipic acid and tetraethylene pentamine is 12240mPa·s and that of the polyamide-2 synthesized from dimenthy tetrphthalate and tetraethylene pentamine is 11800mPa·s. The effect of synthetic polyamide content on the mechanical performance and thermal performance of the epoxy curing system is studied. The results show that overall performance of the curing system first increases and then decreases with the increase of synthetic polyamide content and reaches maximum with 33 wt% of polyamide. The tensile strength, flexural strength and impact strength of polyamide-1/CYD-128 are 32.41MPa, 81.55MPa and 19.6KJ/m2, respectively. While that of polyamide-2/CYD-128 are 37.88MPa, 104.60MPa and 16.5KJ/m2, respectively. This low viscosity curing system can be used as building adhesives due to its excellent mechanical properties.

Simple joint is a common connection in tubular structures, it refers to one or more components soldered directly on the surface of the other member. Local buckling occurs in panel zone when the joint under heavy load, such local buckling will reduce the bearing capacity and stiffness. In order to improve bearing capacity of tubular joints, the joint needs to be strengthened. In this paper, the bending performance of the joint will be enhanced by welding a sleeve inner the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different parameters of inner sleeve was analyzed. The results showed that compare to sleeve length variation, bearing capacity of the joint experiences obvious change with variation of sleeve thickness.

Simple joint is a common connection in tubular structures. Local buckling occurs in panel zone when the joints bear heavy loads, and local buckling will reduce the bearing capacity and stiffness. In order to improve the bearing capacity of tubular joints, the joints need to be strengthened. In this paper, the bending performance of the joints will be enhanced by welding a tile shaped plate outside the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different tile shaped plate was analyzed. The results showed that the bearing capacity of the joints experience obvious change with variation of thickness, whereas the bearing capacity has no change with variation of radian.

For obtaining fatigue limit and dealing with censored data, the" pair- life -weighted” is proposed in this paper. According to the fatigue testing of TA15 electron beam welded specimens, conventional methods and two methods in this article are used separately to calculate the fatigue limit and lognormal distribution parameters of the lives at different stress levels, and C-P-S-N curves are obtained and their corresponding mathematical expressions of 12 groups under 2 Confidence and 6 reliability are expressed as a three-parameter model. The results show that the" pair- life -weighted method " is in good agreement with the traditional method, when the lives have a difference of 3 times at the same stress, the fatigue limit only have a difference of 0.5%, it is the further evidence of the practicability in engineering about the traditional method.

Simple joint is a common connection type in tubular structures. In this joint, one or more tubes are welded directly on the surface of another tube. Local buckling occurs in panel zone when the joint load is heavy, and such local buckling will reduce the bearing capacity and stiffness of the joint. In order to improve bearing capacity of tubular joints, the joint needs to be strengthened. In this paper, the bending performance of the joint will be enhanced by welding two annular plates inside the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different inner annular plate was analyzed, including design bearing capacity and ultimate bearing capacity. The results showed that comparing to annular plate thickness variation, the width variation and interval variation have much more influence on the bearing capacity of the joint.

This study uses quantitative methods to rate content and teaching on a phonics program delivered by computer assisted language learning (CALL). Data was obtained by Questionnaire and analysed using GM (0,N) model of Grey Theory. Results showed a high effectiveness rating and underlined the value of computer assisted language learning in the continuing education programs in the subject University.

This paper is concerned with the controllability of switched linear fractional control systems, and the solutions of expression, necessary and sufficient conditions for the controllability of systems are given later.

According to the global carbon balance, the lost carbon is called missing carbon sinks were taken up by geological. In order to describe carbon sinks mechanism, Maocun watershed was selected as a study area, and choose four sites in different geological background, where the electrical conductivity (Ec), bicarbonate, temperature and PH value are monitored, the results show that: (1) The amount of bicarbonate in sandstone water is less than any karst water, the order of bicarbonate is that: (HCO3-)XiaolongbeiBianyanMaocunchukouBeidiping, and with exogenous water which contain low concentration of bicarbonate flow into the karst area along the water canal, bicarbonate increase step by step until stable; (2)Temperature, hydrophyte photosynthesis are the main impact factors affect on the carbon sinks flux; (3) Exogenous water can aggravate the carbon sinks flux.

Hot-dip coating can improve the longevity of the bolt connection pairs, but may be influence the pairs on the torque coefficient and tensile load. The torque coefficient and tensile loads of three specifications, two strength degrees and two surface states with and without hot-dip coating bolt connection pairs were tested. The results showed both the mean and standard deviation of torque coefficient of the bolt connection pairs were enhanced in case of the hot-dip zinc process, deals with the lubricant MoS2 they were both decreased and closed to the standard values. By contrast, the tensile loads were unaffected by the hot-dip process.

Cylindrical shells are widely used in civil engineering. Examples include cooling towers, nuclear containment vessels, metal silos and tanks for storage of bulk solids and liquids, and pressure vessels. Cylindrical shells subjected to non-uniform wind pressure display different buckling behaviours from those of cylinders under uniform external pressure. At different aspect ratios, quite complex buckling modes occur. The geometric nonlinearity may have a significant effect on the buckling behavior. This paper presents a widely study of the nonlinear buckling behavior of cylindrical shells of uniform thickness under wind loading. The finite element analyses indicate that for stocky cylinders, the nonlinear buckling modes are the circumferential compression buckling mode, which is similar to cylinders under uniform external pressure, while for cylinders in mediate length, pre-buckling ovalization of the cross-section has an important influence on the buckling strength.

Four zinc-rich coatings were applied onto steel substrate and then placed in neutral salt spray for 4000 h in order to study the anti-corrosion performance of the coatings. The results showed that the samples with two kinds of the coatings were more seriously eroded than the others. The reasons could be that the zinc particles were dispersed inhomogeneous in the binder and the zinc content was very lower than 96 wt. % obtained through the analysis of Scanning Electron Microscope and Differential Scanning Calorimetry.

The existing research on flange focused on bearing capacity, and there were few reports on the rigidity of flange. In this paper, rigidity test was carried on for the connection of rigid flange and flexible flange in power-transformed frames. According to the test results, the axial rigidity, shear rigidity and flexural rigidity was compared. The results indicated that the axial rigidity, shear rigidity and flexural rigidity of flexible flange connection was lower than those of rigid flange connection for both the plain bolt and high strength bolt.

Tube-plate joint is a frequently-used joint type in steel-tube tower, but the theoretical analysis and experimental investigation on tube-plate joint are absent both at home and abroad. In this paper, the ANSYS finite element program was used to simulate the bearing capacity and deformation condition of tube-plate joint with 1/2-stiffening ring. Eight calculation models were designed, and the width-thickness ratio was changed by changing the width or thickness of stiffening ring. The results indicate that the influence of different width-thickness ratio on tube-plate joint bearing capability is significant. By increasing the width or increasing the thickness of stiffening rings to improve the bearing capacity of the joint is a very effective way.

Many thin cylindrical shells are used in structural applications in which the dominant loading condition is global bending. Key examples include chimneys, tubular piles, wind generation towers and tall silos. Their thickness lies in a tricky range which is extremely thin for the structural tube community and very thick for the shell buckling community. The buckling strength of these structures is dominated by extensive plasticity, but the fully plastic state is usually far from being attained. This paper explores the buckling strength of imperfect thin cylindrical shells under global bending in the elastic-plastic range. The capacity curves of the new Eurocode EN 1993-1-6 (2007) are used to match the final results. The results show that the capacity curves can capture this buckling behavior accurately and safely for different types of material models. It is assumed that the shell is held circular by rings or boundaries at reasonable intervals, effectively restraining ovalisation. It is hoped that these results will make a useful contribution towards resolving the misunderstandings and controversy that has been evident in this field in recent years.

This study was designed to comparative evaluate the chemical composition of the essential oil from leaf, aerial root, twig, root and bark parts of Ficus microcarpa L.f. (Moraceace). Gas chromatography (GC) and gas chromatography/mass spectrometry (GC–MS) analyses of the oils revealed the presence of 6, 6, 5, 5 and 5 compounds in the essential oils obtained by hydrodistillation from different parts, respectively. The total yield of the volatile fractions was subsequently 1.89%, 0.87%, 1.27%, 0.97% and 0.71%. Higher amounts of aliphatic acids were found to compose a major chemotype in diverse parts of the plant. n-Hexadecanoic acid, elaidic acid and linoleic acid were the main and common component of all the essential oils totally attaining in average 74%, 87%, 56%, 46% and 88%, independently. In addition, some pharmaceutical components such as elaidic acid, linoleic acid and squalene were discovered. The study offers theoretic basis for utilization of the traditional folk herb F. microcarpa.

Full-scale of U-type and grooved-type slotted end plate (SEP) connections are tested to determine their failure modes and damage mechanisms under ultimate loading. Simulate on mechanical behaviors of U-type and grooved-type SEP connections under compression using finite element software ANSYS based on the experimental research. Obtain load-vertical displacement curves of the SEP connections, and compare with the experimental results to determine the validity of the model. On this basis, this paper provide the improved SEP connections, and contrast with the U-type and grooved-type SEP connections. The results indicate that finite element results are in good agreement with experimental data. Difference of the ultimate load between the test specimen and finite element model is less than 10%. The finite element can simulate mechanical behaviors of the SEP connections better. The ultimate bearing capacity of the UC-type SEP connected joints is significantly higher than the U-type and grooved-type, which shows the improved SEP Connections is reasonable and effective. SEP is the main factor of the U-type and grooved-type SEP Connections’ ultimate load, tube is controlling factor of the UC-type SEP connected joints.