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The purpose of this study was to design porous implants with particular structure and evaluate their biomechanical behavior. Thus, a segmented porous dental implant (SPDI) was designed and manufactured by 3D Printing and computer numerical control (CNC) composite machining technology. The FE analysis was used to investigate its static mechanical property. Fatigue test was performed to verify its fatigue life. Resonance frequency analysis and pull-out tests were carried out to study its primary stability. Results indicated that better stress distribution was observed for SPDI. Fatigue test showed that no fracture or failure occurred in SPDI samples after 8 million cycles. The average implant stability quotient (ISQ) values of the SPDI inserted into the porous and denser artificial bones were 68.7 and 73.0 respectively. The average maximum pull-out force of SPDI extracted from the artificial bones was 347.5 N. This study provided a new structural design and manufacturing method for porous implant. The results suggested that the novel porous implant obtained good mechanical adaptability and primary stability.

In this paper, the low cycle fatigue crack initiation life was regarded as a process of damage accumulation and a damage accumulation model was established based on the Continuum Damage Mechanics. By the model, we analyzed how the variable amplitude applied at the crack initiation stage influenced the low cycle fatigue life of high temperature materials. With the parameters of GQGH4169 alloy at room temperature, we determined the specific values of damage parameters by finite element method and numerical analysis method. Then, the crack initiation life predictions were carried out. The results show that using this approach can not only predict the crack initiation life of CT specimen accurately, but also reflect a definite influence of variable amplitude on the crack propagation life combining with the Paris Law, and the test costs reduced consequently.

Natural rubber (NR)/epoxidized natural rubber (ENR)/carbon black (CB), natural rubber/butadiene rubber (BR)/carbon black and natural rubber/isobutylene-isoprene rubber (IIR)/carbon black compounds were prepared by mechanical mixing method. The mechanical properties, dynamic mechanical properties for the compounds were investigated respectively. The temperature range of tanδ>0.3 of NR/ENR40/CB compound was wider and shifted to high temperature than NR/CB compound. Comprehensive analysis indicated that NR/BR/CB and NR/IIR/CB compounds had no better damping performance than NR/CB compounds, while NR/ENR/CB compound had better damping performance.

Based on the theoretical analysis on the coupled vehicle-bridge vibration, this paper simulates the action of the moving vehicle load on a bridge structure with a sprung mass model, and obtains the dynamic response of the simply-supported bridge structure under the moving vehicle load through computation by finite element method (FEM). Through checking computations of classic examples, this paper proves the applicability of this computation method.

The environmental friendly catalyst, H4SiW12O40/TiO2-SiO2 was prepared by the impregnation method. The synthesis of cyclohexanone glycol ketal was as the probe reaction and investigated the different influences on the catalytic activity of H4SiW12O40/TiO2-SiO2 by the quality of the carrier TiO2-SiO2 ratio, load of heteropoly acid, catalyst preparation conditions of the activation time and the calcination temperature, etc. The results showed the best condition for the preparation of the catalyst is the mass ratio of TiO2 and SiO2 is 1: 5, the load ratio of H4SiW12O40 is 10 %, calcination temperature is 300 oC and the roasting time is 3.0 h. Under the condition of the molar ratio of aldehydes (ketones) and glycol (1,2-propanediol) is 1: 1.6, the mass percent of the catalyst is 1.4 %, and the reaction time of 70 min, the yields of eight kinds acetal (ketal) are 71.6 %~ 90.5 %.

A new environmental friendly catalyst, H4SiW6Mo6O40/TiO2-SiO2was prepared by impregnation method, the synthesis of cyclohexanone 1,2-propanediol ketal was the probe reaction to optimize the synthetic condition of catalyst. The reactive condition of catalyst was optimized by orthogonal test method. The optimum conditions are n (TiO2): n (SiO2)= 3: 1, 20 % mass ratio of m (H4SiW6Mo6O40): m (TiO2-SiO2), the calcined time is 3 h and 300 °C of activated temperature. Using H4SiW6Mo6O40/TiO2-SiO2as catalyst, adipic acid was synthesized from the oxidation of cyclohexanone by 30 % H2O2. Influences of dosage of H4SiW6Mo6O40/TiO2-SiO2, reaction temperature, volume of hydrogen peroxide and reaction time were discussed. Experimental results showed that H4SiW6Mo6O40/TiO2-SiO2is a good catalyst for synthesis of adipic acid. When n (cyclohexene): n (H2O2): n (H4SiW6Mo6O40/TiO2-SiO2)= 100: 979: 0.04, reaction temperature is 130 °C and reaction time is 5 h, under the optimum conditions, the yield of adipic acid is 45.9 %.

The organosilicone gel material for large-power LED packaging was prepared through Si-H addition reaction of hydrogen-silicone with vinyl-silicone catalyzed by Pt coordination compound in the paper. The effect of Si-H/C=C ratio on thermal stability, shore hardness, visible light transmittance and tensile properties were investigated by FTIR, UV-vis spectrometer, etc., which supplied the basic data for the preparation and application of organosilicone materials for large-power LED packaging.

It is the function of Geophysical Information Management System to manage these data and provide database for the project decision-making. This paper uses Unified Modeling Language to describe and construct the system model by means of iterative and incremental development method under the guidance of mature Rational Unified Process. The analysis and design of Geophysical Information Management System can not only reduce the risk of failure, but also meet all the users’ requirements.

To study the saccharification conditions of cellulase on lignocellulose material, this paper used corn straw as the material to do research on the effect of cellulase. The hydrolysis factors, including reaction temperature, reaction time and cellulase concentration, were measured in order to determine the optimal saccharification conditions for fuel ethanol production. The results showed that, when the reaction temperature was 45°C, reaction time was 72 h and cellulase concentration was 60 IU/g, the hydrolysis rate can respectively reach 6.25 %, 14.7 % and 14.4 %. By the analysis of orthogonal test, the main factors effects the saccharification was reaction time. And the optimal combination of saccharification conditions was the reaction time of 54 h, the reaction temperature of 45 °C, and the cellulase concentration of 55 IU/g.

Cu2O-MoO3 composites has been successfully fabricated by solution-phase reducing method at room temperature. All the powders were characterized by X-rays diffraction (XRD) and scanning electron microscopy (SEM), and explored the catalytic activity for the photocatalytic degradation of methyl orange. The effect of different factors on the degradation was investigated. The best reaction conditions were found out. The results demonstrated that initial concentration of methyl orange is 5 mg/L, the pH is 4, the catalyst dosage is 0.38 g/L and the H2O2 is 1.8 mL, the degradation rate of methyl orange is as high as 95.4% after 30 minutes simulated natural light irradiation.

The present study was carried out to investigate anti-hypoxia and anti-fatigue activities of flavonoids from bark of Eucommia ulmoides (FEU) in mice. The animal were divided into four groups: control (C) group, low-dose FEU treated (LF) group, intermediate dose FEU treated (IF) group and high-dose FEU treated (HF) group. The treated groups received FEU (5, 15, 45mg/kg), while the control group received saline solution for 28 days. After 28 days, anti-hypoxia activity of FEU was assessed by the normobarie hypoxia test and anti-fatigue activity of FEU was assessed by the forced swimming test. The data showed that FEU could prolong survival time of oxygen deprivation and exhaustive swimming time by reducing BLA and BUN levels and increasing liver glycogen and muscle glycogen contents. Therefore, FEU had anti-hypoxia and anti-fatigue activities.

Possible ways to remove fluoride from phosphoric acid are extraction,but there are always generated a second organic phase ,where still have small amounts of impurities such as fluoride,sulfate,iron,aluminum and heavy metals. The traditional process using pure water or dilute phosphoric acid washing the organic phase to get phosphoric acid ,but the impurities removing rate is not obvious.This study explore a new way to changes the washing detergent,using dilute alkali solution to reduce fluoride content of stripping in phosphoric acid.The optimization of experimental conditions is dilute alkali mass fraction 20%,dosage 0.4%,temperature 45°C,the defluorization rate can be 67.75% and phosphorus pentoxide yield rise to 95.50%.This study provides a new idea to improve defluorination rate in industrial production.

Ad hoc is a new kind of wireless, jump, and no center distributed control network, it does not need network infrastructure, strong self-organizing, robustness and so on. Routing protocol is an important part of Ad hoc, good routing protocol is the first problem of establishing Ad hoc three kinds of routing protocol (DSDV, DSR, ZRP) is introduced in the paper, in the experiments, we use OPNET network software to simulate the above three routing protocol, Finally analysis the grouping deliver rate, routing overheads, business, the time delay, etc., concluded results.

The effects of mole ratio of formaldehyde and melamine (F/M), solution pH, reaction temperature and time on the foaming melamine-formaldehyde resin (MF resin) with caprolactam as modifier were investigated by orthogonal experiment design where the solid content and the viscosity of the resin, the density and the size uniformity of the foam resin were used as performance evaluation parameters. The results had shown that the optimal conditions for preparing the foaming MF resin were F/M= 3.25, pH=8.0, T=90°C, t=45min. The MF resin prepared under the optimal conditions could be foamed well and its storage time was prolonged to 16 days. The structure and thermal properties of MF resin under the optimal conditions were investigated.

Red sandstone with a strong water softening can cause difficulties of construction projects, especially for slope excavation and support engineering. Therefore, the study on the engineering properties of saturated red sandstone has a important meaning. The mechanical parameters of saturated red sandstone are obtained by the triaxial compression tests. The test results indicate that the ralations between peak strength, elasticity modulus and confining pressure for the saturated specimens are similar with the natural specimens, that is, with the increasing of confining pressure, the peak strength and the elasticity modulus will increase, but the growth rate becomes slowly. Under the same confining pressure, the peak strength and the elasticity modulus of saturated specimen are more smaller than the natural one. The mechanical damage caused by water recedes when the confining pressure increases, so for the geotechnical engineering with larger influence of water, the increasement of confining pressure by the supporting structures is conducive to the stability of rock mass. The research results will provide a theoretical basis for the red sandstone engineering.

The management of user permissions is one of the basic and important functions to ensure the safety of a management information system. Firstly, this paper analyzes the shortcomings of the tow kinds of access-control methods generally used; then brings forward an algorithm of Traversal system menu items and stored the items in database; finally, realized the algorithm in C# with an application. By using the algorithm of traversal menu items, user permissions of a system can be controlled easily and dynamically.

Groundwater refers to the subsurface water that occurs beneath the water table in geological formation that are fully saturated. 95% of the water used for human production and living comes from groundwater. But now, the pollution degree of groundwater resources is serious, which is a serious threat to human. In order to capture groundwater pollution's situation, groundwater pollution detection should be carried out. Because of the geophysical methods are of low cost, high speed and the characteristics of in-situ nondestructive, people often used geophysical methods for groundwater pollution detection. Geophysical prospecting contains a lot of methods, and the researchers often use resistivity sounding method, ground penetrating radar method, high density resistivity method and seismic reflection method to detect the pollution condition of groundwater.

With the continuous development of large-scale, high-speed ship, considering economy and security of the ship, propeller design and performance research are of importance. In this paper, the best propeller is obtained by using the propeller design software HydroComp PropExpert and HydroComp PropCAD. Propeller geometry model is generated by Solidworks. Applying computational fluid dynamics method (CFD), we can take numerical simulation for the flow around the propeller. Finally, with the help of the software ANSYS, hydrodynamic performance of the design propeller can be forecasted. The results from the calculation and analysis can provide some reference for engineering practical problems and theoretical study.

In this paper, the process of the developments and changes of the network intrusion behaviors were analyzed. An improved epidemic spreading model was proposed to study the mechanisms of aggressive behaviors spreading, to predict the future course of an outbreak and to evaluate strategies to control a network epidemic. Based on Artificial Immune Systems, the concepts and formal definitions of immune cells were given. And in this paper, the forecasting algorithm based on Markov chain theory was proposed to improve the precision of network risk forecasting. The data of the Memory cells were analyzed directly and kinds of state-spaces were formed, which can be used to predict the risk of network situation by analyzing the cells status and the classification of optimal state. Experimental results show that the proposed model has the features of real-time processing for network situation awareness.

In this paper, a trustworthy QoS unicast routing scheme based on trustworthy network is proposed. First, a cognitive network model is designed, referring to the intelligence of artificial immune system. Then, trustworthiness of each node is evaluated by deploying sliding window mechanism and analyzing the behavior record of each node. Finally, a population adaptive based immune of trustworthy QoS unicast routing algorithm is proposed, referring to the adaptive process of antibody identifying antigen. We verify the effectiveness of our scheme by using large-scale computer emulation experiments and compare it to existing classical algorithms. The results show that the proposed algorithm is both feasible and effective for providing users with better QoS, etc.

The samples are prepared by vacuum sintering technology, and the effects of VC/NbC combined addition on the mechanical properties of the WC-8% Co alloys with superfine grain are investigated. The results show that: with the transformation of Co-doped inhibitors content, the grain growth is inhibited and the grain size 460nm at 0.4%NbC/0.4%VC. The mechanism that Co-doped NbC/VC on the effective reduction of ultrafine WC-8%Co cemented carbides was analyzed. The 0.4%NbC/0.4%VC addition equipped with the best integrated properties was obtained in this study. And sintered sample were investigated with SEM.

In order to tunnel safely, efficiently and economically, we carried out the study on geostatic stress characters and optimizing bolting support parameters in 2# coalbed of Zijin Colliery. Based on the surveys of geological conditions, original rock stress, broken rock zone measurement and analysis of roadway deformation, characters and mechanism of roadway failure is figured out. According to existent problems, normal support theories were used and a variety of numerical computations were carried out by FLAC3D.New support methods of bolt installed vertically in tilted roof and strengthen support of sidewalls and corners of roadway were figured out. Monitoring of convergence meters and roof separation were followed to know effects of new design timely. The research was carried out for 600 meters The monitoring results proved that the optimized support design was viable and the new bolting parameters were reasonable.

For the current popularity of "green building" concept, traditional architectural design teaching model is monotonous. The papers analyze the architectural design teaching problems in context of the New Times conditions. Green building concepts combine to architectural design with putting ecological ideas into the whole teaching of architectural design. The open teaching use mode "raise questions - analysis of the problem - solve the problem" to enhance learning ability. Finally, under the guidance of green building concept the results of teaching evaluation system need to reform.

It is a hard engineering problem for the shield machine passing through the capital airport apron in shallow soft soil. Tunneling parameters were obtained from the 50m simulation test section ahead the apron. The shield machine kept tunneling steady and balanced by optimizing the control technology of soil pressure and grouting. According to the monitoring results, the secondary and repeated grouting technology was applied timely. The deep splitting grouting technology was used when the monitoring value exceeding control standards. The settlement value was effectively controlled.

The traditional real-time video surveillance system at smart home tends to occupy a lot of resource .In order to solve this kind of problem, a design of an infrared sensor to trigger video monitoring system is proposed in this paper .The system uses arm9-Linux as the platform ,and infrared sensor as the trigger device and uses the mpeg-4 algorithm to encode the video stream finally .The article mainly introduces how to build the hardware and software platform and tests the feasibility of the system.

A kind of straw returning and fertilization seeder was designed. The overall structure and key technologies were introduced. The structures and parameters of the key parts were determined. The teamwork machine has a reasonable and compact structure and wide applicability, which can realize straw chopping, tillage, soil preparation, seeding, fertilization and compacting.

The work focuses on synchronization of time-delay chaos systems. A theoretical analysis for time-delayed system is provided. By using the Lyapunov-Krasovskii approach, a synchronization condition is obtained. Finally, conditions are used for synchronization of time-delay chaos systems, and simulations verify the validity of obtained result.

Invasive aquatic species has been considered one of the greatest threats to the worlds oceans and marine ecological system. A novel of ships ballast water treatment based on ion exchange membrane electrolysis system to deal with algae has been proved. In this paper, an optimized treatment for inactivating algae is proposed based on the developed ballast water treatment system. In this optimized method, different experimental conditions are studied, which contain the injection times and small injection dose of anodic electrolytic products. The contrast experiments were conducted, the results show that the lethal time and available chlorine dose can respectively save up to 66.67% and 50% under the optimized method. The results show that the proposed have the more efficient kill ability for the algae life.

Ship ballast water has been identified as one of four major environmental threats by the international maritime organization. This paper presents a portable on-site rapid detection system of microalgae in ship ballast water. The system consists of a microfluidic chip platform, LED light source and drive systems, optical detection system, ARM software and hardware system, power supply system and so on. Microalgae particles can go through the detection area inside the micro channels one by one by using a sheath fluid focus. The resulting chlorophyll fluorescence is converted to the electrical pulse signal by photodiode. The experimental results show that the system can quickly and accurately detect the ballast water living microalgae concentration. The minimum detectable microalgae size is about 3μm (mean diameter). This system has some advantages such as miniaturized, portable, fast, accurate and label free, and has great potential for on-site rapid detection of ship ballast water.

Evaluation of radiation dose is very important for the detection of radiation damage. γ-H2AX is a popular biological dosimeter to evaluate the radiation effect. Typically, bulky and expensive commercial flow cytometers are used to detect γ-H2AX. This paper presents a miniaturized and highly sensitive cytometer using a microfluidic chip for evaluating the radiation dose by detecting the mean immunofluorescence intensity of γ-H2AX. A compact optical focusing system and a shift-phase differential amplifier are designed to improve the detection sensitivity. Sample lymphocyte cells are stained by FITC fluorescent dye after being irradiated by UVC. Comparison experiments between the developed miniature cytometer and a commercial flow cytometer were conducted under different radiation doses. The developed microfluidic cytometer can also demonstrate a good linear correlation between the measured fluorescence intensity and the irradiation dose with a detection limit similar to that of the commercial flow cytometer. The developed cytometer can evaluate quantitatively the radiation dose by the mean fluorescence intensity of γ-H2AX with a significantly smaller amount of blood samples than a commercial flow cytometer.

Fish scale, a by-product of fish processing, contains abundant of hydroxyapatite. Boiling fish scale in alkaline solution can fabricate adsorbent for sewage treatment. Degumming experiment had been investigated by exploring different heating time. Adsorption experiment had compared the adsorption effect of carmine by different fish scale sample. The results indicated that degummed fish scale had the best adsorption effect for containing both surface adsorption by hydroxyapatite and electrostatic adherence by collagen.

In engineering quality inspection and acceptance and evaluation of structural properties, the quality of structure real object is paid more and more attention to by all parties involved in construction. But the structural detection technology and corresponding rules are lagging. Through the use of the same batch of concrete structure and frost resistance of concrete test block test, the results show that for the same concrete mix, the frost resistance of standard preserved test block is better than that of the core samples drilled from concrete; as for the mixture ratio, the forming and curing conditions are exactly same as the concrete, and the preserved test block frost-resistance performance is also superior to that of concrete core-sample.

Based on the probability theory, combined with the deterministic method for estimating the fatigue fracture mechanics, the formula was deduced to calculate the fatigue crack propagation life of examples components. The uncertainty and randomness of main assessment parameters were considered:initial crack size, practical working load,fracture toughness, mechanical intensity and coefficients. Since there are not many data, Weibull distribution was adopted to denote the life distribution of equipment approximately. A computer program was developed by using numerical integration method, and the fatigue life under given reliability and credit degree was solved. Analysis result shows that MonteCarlo simulation method can reflect objectively the uncertainty of assessment parameters and overcome the shortcomings of certainty assessment methods.

Waterbased phenolic resin/silica hybrid material was prepared by situ polymerization using TEOS (tetraethyl orthosilicate) as precursor. Effects of pre-hydrolysis condition of TEOS and TEOS content on the formation and stabilization of the hybrid material were studied. The flammability of the prepared composite material was studied by TGA (Thermo gravimetric analysis), LOI (limited oxygen index) and UL-94 test. The results show that stable waterbased hybrid material can be prepared when the amount of ammonia is 0.020g. TGA, LIO and UL-94 test result show that the hybrid material presents better flame retardancy.

From the analysis of the character of elastic wave through a rock medium, According to the safety driving problems faced in tunnel construction geological prediction, using TSP test data inversion of rock hardness, integrity and water characteristic parameters, the determination model of surrounding rock classification based on the variable fuzzy sets for surrounding rock classification. You can use the existing geological forecast means the achievements, with no increase in the additional cost method, the use of advanced, scientific method, in situ on surrounding rock grade determination, not only reduced the economic investment, and reduce the detection procedure, which have greatly improved invest. From detection technology investment and time efficiency compared to the original method, to guide the construction, save the cost, construction scheme design plays a positive role. This method not only has the profound theory value, but also has significant social benefits and huge economic benefits.

The embedded boost power factor correction (PFC), which is realized by a storable duty cycle control method, has been verified that it can achieve good performance when the input voltage is standard sinusoidal signal. But the input current can not keep the good sinusoidal waveform all the time when the amplitude of the input voltage changes. In order to solve the problem, this paper presents a duty cycle adjustment strategy for embedded boost power factor correction. This strategy can adjust the duty cycle data synchronously when the amplitude of the input voltage changes. Its test results show that the adjustment strategy can achieve better performance to make the input current follow the shape and phase of the input voltage. The proposed duty cycle adjustment strategy can get the embedded boost power factor correction more effective and practical.

This paper proposes a new digital constant-current control method for high-power LED drive based on buck-boost topology. In this control system, buck-boost topology is used as the power conversion. The output voltage can be either higher or lower than the input voltage in buck-boost topology. Therefore, it solves the problem that in the buck topology the input voltage is required to be always higher than the output voltage. Furthermore, according to the input and output parameters, the duty cycle data which are used to maintain output current constant can be calculated in advance, and stored in the embedded chip. Thus, it can reduce the calculation of the embedded chip and solves the problem that the existing digital constant-current controllers need the high-speed analog-to-digital converter. In addition, in order to reduce the error generated in above calculation, the double threshold feedback circuit is used to fine-tune the duty cycle and makes the output current more steady and accurate. Meanwhile, due to adopting full-digital control, the brightness and flicker frequency of load LED can be conveniently regulated by modifying the system firmware. Therefore, this method can apply to the device of illumination, lighting decoration, visible light communication and so on.

Based on SL1126 internal combustion engine, using development mode based on secondary development with the underlying language (VC++6.0) and large scale software package, we study the overall structure of simulation system of internal combustion engine assembling, and build the parameterized model of internal combustion engine. And then, with the model, we perform transient analysis on the crank-link mechanism of the internal combustion engine via many-body dynamics, getting the life, velocity and change pattern of acceleration of piston. The analysis data can direct the improvement of internal combustion engine.

The research on drillstring dynamics is necessary for improving drilling efficiency and safety. In this investigation, a multibody dynamical model for 3D full hole drillstring system is presented based on the Absolute Nodal Coordinate Formulation (ANCF). The drillstring is modeled with the ANCF beam element. The absolute nodal coordinate formulation of the beam element as well as the boundary conditions at the top-drive and drill-bit, and the contact/friction model between drillstring and wellbore are also investigated. The dynamic governing equation for full hole drillstring system is given and solved by the backward differentiation formulation (BDF) for differential algebraic equations (DAEs). The developed multibody dynamic solver is capable of analyzing full coupled vibration for the full hole drillstring system. It can play a certain role in drillstring dynamics researches and engineering applications.

This paper analyzes the shortcomings of the traditional AHP method and proposes group decision making from a single decision-making. In group decision making the weight of experts is very important. This paper discusses the existing methods of determining experts’ weights, introduces the method of the similarity of the cosine of the vectors’ angle, and the weight of experts is determined dynamically according to the similarity of the judgment matrix given by experts. When determining the weight of experts, judgment matrixes experts give need to pass the consistency test. In this paper, AHP group decision making method is applied to the load balancing system to determine the index weight influencing on load balancing. The experiment in the paper shows that this method can reduce calculation of consistency test and make the decision-making results more effective.

Carbon decomposition of liquor afger desilication from nephine was investigated, aluminium oxide was prepard by anneal of Al (OH)3 separated out from carbon decompositon, and analysis of radionuclide of both above process was performed. The results show decomposition rate of sodium aluminate can be obtained when experiments of carbon decomposition of liquor after desilication using CO2 of hight concentration, and it is beneifit for the crystal growth of Al (OH)3, filtration and separation. Great mass of nuclide exists in the mother solution of carbon decomposition, and few into Al (OH)3, which could be regarded as wiout radioactive contamination. .

Using aqueous hydrogen peroxide solution (30wt%) as oxidant, potassium bisulfate (KHSO4) as acid ligand, adipic acid was synthesized with cyclohexanone as raw material and H4SiW6Mo6O40/SiO2 as catalyst. The factors influencing the synthesis were discussed and the best reaction conditions were found out. Experimental results showed that H4SiW6Mo6O40/SiO2 is an excellent catalyst. The optimal conditions are: n (cyclohexanone):n (H2O2)=1:4.0,catalyst dosage is 0.4g, mass of acidic ligands is 0.1g, and the reaction time is 4 h, the yield of adipic acid can reach 93.7 %.

A novel catalyst, H3PW6Mo6O40/SiO2 was prepared by a sol-gel technique, and characterized by FT-IR and XRD. Using aqueous hydrogen peroxide solution (30wt%) as oxidant, sodium bisulfate (NaHSO4) as acid ligand, adipic acid was synthesized with cyclohexanone as raw material and H3PW6Mo6O40/SiO2 as catalyst. The factors influencing the synthesis were discussed and the best reaction conditions were found out. Experimental results showed that H3PW6Mo6O40/SiO2 is an excellent catalyst. When n (cyclohexanone):n (H2O2) : n (H3PW6Mo6O40/SiO2):n (NaHSO4) = 100:440.7:0.21:0.74, reaction temperature is 90°C and reaction time is 6 h, the yield of adipic acid can reach 90.2%.

An indicator system is established for the suitability of projects linked to the increase/decrease in urban and rural construction land based on the field surveys for the old areas to be dismantled in three administrative villages such as Niulandian Village, Tianjiagou Village and Nanchongsi Village of Tianchi Town in Lezhi County of Sichuan Province, and the fuzzy comprehensive evaluation method is used to evaluate indicators. The analysis of evaluation results provides reference for the efficient implementation of projects linked to the increase/decrease in urban and rural construction land.

Keywords: strain, stress, material constants, constitutive equation, anisotropy. Abstract. If the material is anisotropic, there are differences in stress distribution under the same boundary conditions when it was simplified as an orthotropic material. We established a simple finite element model for rectangular perforated planar material, in which one side was fixed, the opposite side was loaded with uniform force, and the other sides were set free. Based on this model we studied the difference of distribution of stress between anisotropic material and its simplified form, orthotropic material. The results showed differences in some cases quite large, the maximum relative error of extreme stress can reach 341%. In conclusions, this study does not support that the complex anisotropic materials are simplified to orthotropic materials. If researchers only concern the location of extreme stress, this study does not deny that the complex anisotropic materials can be simplified to orthotropic one.

Ultrasonic method is a considerably mature method to test the defects of concrete. As for a certain dam deep crack with merely one test surface, the operations can be done such as drilling holes on both crack sides, filling clean water as coupling agent and finally the crack depth is tested with cross-hole sonic logging, subsequently, the data processing and depth judgment with the test principle of the said method. The result manifests that before grouting treatment, the measured dam crack depth is 1.2~9.0m, and the tested point wave shape has not been obviously abnormal and the criterions of wave amplitude and wave speed against the intact local concrete remain no greater differences and the cracks grout in the tested zone are generally solid after the grouting.

The appearance of commercial concrete has heightened architectural construction level, improved construction civilization and offered the guarantee of the popularization and application of new tech significantly. Meanwhile, its popularization has brought the issues of structural solid concrete strength test and early plastic cracks. Currently, the solution for commercial concrete structural strength test is mainly done by means of method of non-destructive test of core-drilling correction. Merely the primary analysis can be done over the early plastic cracks to find no reasonable explanation toward those cracks, nor define the responsibilities of the related subjectival responsible parts that cause the cracks.

A residential building, a brick/concrete structure built up in 1990s was used for many years. Since a deep foundation pit construction was being done in the north, the residents were worrying about the cracks in the building and its safety. Therefore, the following works were done such as the spot checks of the building engineering quality were done; the test and analysis were carried out over the cracks development after the foundation pit was backfilled, the influence assessment of the foundation construction under the mutual effects of pilings and anchor rods over the residential building structure was also conducted; finally the recheck calculation and safety evaluation were made over the building structure. The result shows that the foundation digging leads to new cracks on the nearby residential building but does not endanger its structural safety; after the foundation was backfilled, the hidden danger on the building’s northern side slop was eliminated and the structure cracks tend to be stable; the complete engineering structure is safe and in conformity with the requirements of safety and anti-vibration during the construction period, however, the multiple-pore slabs’ piecing affects the structural integrity and vibration proof performance.

The constructional decoration and constructional flooring projects are the important parts in constructional engineering and currently the qualities of face tile attachment and plaster layer adhering are checked by means of visual observation and gentle knocking with small hammer after the end of project. However, the said conventional visual observation and knocking test methods are more in subjective randomness and low in efficiency to result in poor inspection effect. With the principle of the rebound value being abnormally quite low in case there are air holes or hollowing in the process of compressive strength test of materials with rebound method, the hollowing defect distributions in constructional flooring and architectural decoration engineering can be detected completely, accurately and visually by means of reasonable test point layout and effective defaults judgments.