Search

The precursor thienyl-group-bearing acrylic polymer (TE-PAA-co-PMMA), obtained with 3-Ethyl acrylate-thiophene (TE-AA) and methyl methacrylate through free radical polymerization, was prepared electrochemically to free-standing, processible and conducting conjugated PTE-PAA-co-PMMA film by direct anodic oxidation in CH2Cl2 containing 50% boron trifluoride diethyl etherate (BFEE). The structure, electrochemical, optical, thermal properties and morphology of as-formed electropolymer were systematically investigated by FT-IR, cyclic voltammetry, UV-vis, thermogravimetry and scanning electron microscopy. Cyclic voltammetry studies demonstrated that the precursor can be reversibly oxidized and reduced accompanied by obvious color changes from dark blue to transmissive yellow-green and the electropolymer has good redox activity as well as excellent electrochemical stability. Additionally, fluorescence spectra show that the so-obtained crosslinked polymer is still good blue-light emitter.

The controllable synthesis of special shape of nanoparticles with uniform size was most important for some special applications. In this work, we prepared silver nanocubes by Na2S-mediated polyol synthesis using AgNO3 as precursor, polyvinyl pyrrolidine(PVP) as capping agent and ethylene glycol(EG) as solvent and reductant under the protection of Ar characterized by SEM, UV-vis, DLS and Zeta potential. Silver nanocubes were successfully controllably obtained via optimizing the reaction conditions, such as the rate of Ar initially after 50 min pre-heating and subsequently after the addition of AgNO3 solution，the volume of 3 mM Na2S solution. The results showed that silver nanocubes with edge length of 50 nm and sharp corners were achieved at 230μL 3mM Na2S solution added under a Ar rate of 1000 ml/min.

SHARON-anammox process is a new energy-efficient biological denitrification process. In this paper, the basic principles of SHARON and anammox were introduced. Technical characteristics and present research status of SHARON-anammox process were analyzed, and existed questions and development trend were put forward.

Using municipal sewage treatment plant sludge as the inoculation sludge, anaerobic ammonia oxidation experiment started in a UASB reactor with an effective volume of 3.5L. The experiment lasted 116d, experimental medium term, the system NH4+-N, NO2--N removal rates were above 50%. Changing influent load will cause a greater impact on the reactor, resulting in fluctuations of NH4+-N and NO2--N removal rate. Late, NO2--N / NH4+-N values ​​remain at around 1. The sludge in the reactor changed from gray-brown to pink. The system is more stable for removing NH4+-N and NO2--N.

With the development of science and technology as well as the transformation of the social culture, the packaging forms turn to be more and more diversified, the packaging materials become more and more abundant, and the packaging processes are more and more improved. However, along with it, some problems brought by product packaging come out gradually and play a critical role which cannot be neglected on the products, consumers, natural environment and so on. To have a correct understanding of the relationship between packaging and environment is conducive to guiding people to pay high attention to the environmental protection when developing packages, insist on the principle to synchronize packaging development and ecological environment protection, and reduce the pollution of packaging to environment to the lowest degree. It should start from the angle of the sustainable development of ecological environment, to study the materials and form design of packaging, thus finally realizing the integration of design and production, production and consumption, packaging and environment, as well as life and ecology.

A trunk lid plate is taken as an example and Fiberglass-reinforced PET material is used to replace steel for weight-saving in this paper. Chooseinjection molding as plates forming methodto find the optimal parameters in given range. To predict plastic parts warpage under different injection parameters and find the optimal parameters, the method of Artificial Neural Network (ANN) is used.

In order to reduce the damage of deicing salt to green belt soil in highway, the research used organic multi-fertilizer SFO featured with water conservation and anti-deicing salt to test the effect on plant growth and soil moisture and ion composition in Jingcheng high way, Beijing, It set 12 t/hm27.5 t/hm24.5 t/hm2 dosage processing in test Experimental index include plant growth, soil moisture, ion composition and the improvement effect of saline-alkali soil. In treatment of 4.5 t/hm2 and 7.5 t/hm2 SFO dosage, the fresh treetop growth of Juniper were increased 25.9% and 85.7% higher than that of CK, but less than that in treatment of 12 t/hm2 dosage. The soil moisture in all treatments was improved 0.8% -2.1% high than that in CK. The analysis showed that SFO can regulate the ion balance of soil, Ca2+Mg2+K+ content of soil in all treatments were raised as the increasing of SFO dosage, but the Na+Cl-ion contens decreased 38% and 48% on average than that of CK,and the Sodium Adsorption Ratio (SAR) significantly was reduced markedly. In which the 7.5 t/hm2 dosage treatment of SFO is the best effect. The results certificated that SFO has the comprehensive effect on reducing soil salinization and can improve soil structure and the soil moisture, and can be applied in controlling soil salinization of green belt caused by using deicing salt in high way widely.

Ascendency theory which is developed by Ulanowicz is an index of activity and organization in living systems and is about to quantify the whole-system status. Being calculated in terms of flows, the ascendency is used to quantify the eutrophication of the ecosystem. However, when network magnitudes and topologies are changed from non-eutrophic to strongly eutrophic, the ascendency which is calculated in terms of flows of simple energy is relatively insensitive to such changes. However, when the flows are measured in terms of eco-exergy, it is more advisable. The ascendancies of two different trophic levels which are non-eutrophic and strongly eutrophic are calculated on simple energy and eco-exergy respectively. The analysis of ascendency about the two different trophic levels also proves that ascendency is more sensitive when based on eco-exergy than on simple energy. The ascendency based on eco-exergy is more appropriate to quantify the ecosystem status.

Infrared focal plane array (IRFPA) bad pixel correction as a prevalent problem is widely used in complex conditions. Therefore, scene-based adaptive iteration bad pixel dynamic correction algorithm is proposed and explored. Adaptive filtering bad pixel detection algorithm is to record the intensity of an image and replace the intensity of the image filtered by a locally acting adaptive filter. Using the intensity of the unfiltered and filtered image to determined the bad pixel which regarded as image noise. By the improved Nagao filtering bad pixel compensation algorithm, filtering sub-windows with the same pixel amount whose patterns are decided by the texture analysis can obtain stronger directivity. Thus, the image boundary pixels do not reappear as flicking dot during the quick scene changes, and the rich scene details are preserved.

For complex application layer protocol of low altitude communication system which may be implemented with several wireless communication technologies which include BeiDou Navigation Satellite System, 3G, Digital radio, GPS, ADS-B, etc., we design a low altitude communication protocol conversion process based on pattern match to enhance the capacity of low-altitude flight service stations processing multi-source information from low-altitude aircrafts or other stations. In the process, the application layer protocol of information is identified with the algorithm based on BM pattern matching and CAM multi-pattern matching fusion firstly, secondly, the common intermediate protocol information is produced, and target protocol information is generated finally.

Small mesh grid is mostly used as flocculation equipment in present water plant, and its head loss is closely related to flocculation effect. Flocculation tank installed with several grid groups in different mesh sizes were tested with a view to evaluating its head loss characteristics, including the frictional and local head losses. The tests were carried out at pilot scale, using a steel tank as flocculation basin. The grids are made of plastic material and the cross section size of the grid trips is 7 mm in width and 2 mm in height. The results indicate that relative roughness is most associated with frictional resistance coefficient (FRC), whereas Reynolds number was unrelated to that. The ratio of frictional head loss to total head loss of the basin does not vary with the variation of channel velocity, and the ratio is always less than 6% in this case. Local resistance coefficient (LRC) decreases with the increase of mesh size. In order to improve the utilization rate of head loss, the preferred mesh size of the grid should be 30-40 mm. The optimal space between the neighboring grid layers can maximize the utilization of turbulent kinetic energy loss generated by grids.

For the reliability analysis of domain software researching to present a comprehensive reliability analysis method of domain software based on evidence,and to establish the working framework. To form reliability evidence through analyzing and measuring the evidence that collecting from the software lifecycle, and to build up a evaluation mode to expression the reliability requirements;to define reliability degree and mapping method based on evaluation mode, and to describe software reliability by reliability degree; to analysis modeling the reliability based on formal methods, as well as to verification and validation models. The method combined of informal evaluation and formal analysis modeling has good maneuverability and good practicability. It can describe the reliability of domain software clearly, and provide support for constructing complete formal high reliability software.

Power model, linear model and hyperbolic model were commonly used to estimate forest biomass via stand volume, however the relative accuracy is unclear forPinus tabulaeformisforests in China. In order to compare the accuracies of these models, data from 130Pinus tabulaeformisforest stands were compiled from published literatures. Data of 100 stands were randomly selected to establish regression equations, the other 30 data were used to compare the accuracies of equations either established in this study or in previous studies. The results show that biomass ofPinus tabulaeformisforests could be well estimated by power model and linear model, while hyperbolic model is likely to result in enormous overestimation or underestimation. The mean relative errors of the power model and linear model established in this study are-0.3% and 1.8% respectively. In comparison with models established by previous studies, these two models have better prediction accuracies.

In order to investigate the effect of stand age and climate hydrothermic factors on aboveground biomass accumulation (ABA), data from 65 typical Pinus tabulaeformis forest stands were compiled from published literatures. By means of stepwise multiple regression, the variations in ABA were examined across the range of stand age and gradients of mean annual precipitation (MAP) and mean annual temperature (MAT). For comparison, stand age was also used as explaining variable alone. The results show that, stand age and MAP could explain 85.1% of variation in ABA, the predictive power is much better than stand age alone. The explanatory power of stand age and MAP were 70.7% and 15.3% respectively. In comparison with stand age, MAP has a relatively poor but significant effect. ABA is not significantly related to MAT, which implies that water availability is more important than thermal condition for ABA of Pinus tabulaeformis forests.

The mechanical response of lightweight concrete multiple shear rivet pavement on the steel box girder bridge deck under wheel loading are analyzed by finite element method. Besides, the effects of various distance、diameter、height of shear rivet to pavement, are researched as well as the effects of thickness of lightweight concrete. Then some recommended parameters are put forward for the paving project.

Squalene, a natural antioxidant, was microencapsulated by the method of ultrasonic spraying and freeze-drying using shell materials of gelatin and arabic gum. The suitable condition for ultrasonic emulsification before ultrasonic spraying and freeze-drying was frequency 28 kHz and running time 20 min. The reasonable condition for microencapsulation of squalene by ultrasonic spraying and freeze-drying was gelatin 3.0 %, arabic gum 5.0 %, maltodextrin 6.0 % and sucrose ester 0.9 %. The appearance and size of microcapsules of squalene were measured by scanning electron microscope and metallographic microscope. The microcapsules of squalene were smonth spheres at the diameter of about 10 μm.

A novel chemical deposition process based on aurous-glycine complex was reported in this paper. By using single factor’s and orthogonal experiments the optimal plating index has been gotten and they are: pH=4~6,[Au]=1.5~2.5 g/L , temperature 40~55 Ċ and plating time 6~8min respectively. Deposition results and quality inspection of the plated panels show that its plating rate is as fast as that of the gold-cyanide complex and reaches 0.020~0.025 um/min, and the quality related parameters including appearance, adhesion power and gold thickness can meet the standard of the modern PCB products.

Three different quenching media (water, oil and air) were used to compare the effect of cooling rate on the microstructure and mechanical properties of SA508-3 steel. The result has demonstrated that the microstructure for water-quenched specimen is the mixture of martensite and lower bainite, for oil-quenched specimen is the mixture of upper bainite，lower bainite and a little martensite, while for air-cooled specimen is mostly granular bainite. The product of water and oil Q&T was tempered martensite with qualified mechanical properties. The air-cooled granular bainite was translated to massive and allotriomorphic ferrite during tempering, which had poor mechanical properties. To avoid the formation of granular bainite, it is necessary to increase the cooling rate to above 5°C/s.

The NaA/PTFE composite membranes were synthesized on polytetrafluoroethylene (PTFE) film by hydrothermal secondary growth (HSG) method and scratching (ST) method. The structure and morphology were characterized by XRD and SEM. The pervaporation(PV) performance of NaA/PTFE composite membranes were evaluated with dimethylformamide (DMF)/water mixtures. The XRD results showed that NaA/PTFE composite membranes kept the zeolite crystal feature of A type. The substrate, PTFE and zeolite were firmly combined together by the SEM photos. The results of PV showed that the flux and the separation factor of NaA/PTFE composite membrane prepared by HSG method with 4 crystallization times were 0.54 kg/m2 h and 23, respectively. The flux of NaA/PTFE composite membrane prepared by ST method was much larger than that of NaA/PTFE composite membrane prepared by HSG method, but separation factor was lower.

Three kinds of commercial PVA composite membranes with different crosslinking degrees (PVA-1, PVA-2 and PVA-3) were used to separate DMF/H2O mixtures. Their pervaporation performance was investigated at different operation temperatures. The results showed that PVA-1 was the most suitable one for separating DMF/H2O mixtures. When operation temperature was 60°C and downstream pressure was lower than 6kPa, flux reached to 0.59 kg·m-2·h-1 and separation factor was 33 for PVA-1 membranes. Aspen Plus® was applied to simulate the normal distillation for retentate from pervaporation unit. Comparing with the two-effect distillation, the cost of concentrating DMF could be reduced 16.2% to 19.2% for DMF aqueous solution with different composition by hybrid processes. The cost would be the lowest for a hybrid process that concentrated the feed into 50wt% by pervaporation firstly, then concentrated retentate to 99.6wt% by two-effect distillation

Dump truck subframe is an important bearing components which is used for connecting the chassis frame and the cargo compartment, and the rationality of its design has an extremely important influence on performance of the entire vehicle, moreover, the use of CAE technology can optimize the design of the subframe. In this paper, using solid element as basic element, the finite element analysis model of dump truck frame is built up with the software ANSYS, the static characteristics of the subframe under bending mode, twisting mode, braking mode and lifting mode are studied. The dynamic characteristics of the subframe are also analyzed, the stress parameters under static characteristics, the natural frequency and the corresponding mode shape characteristics of the subframe under dynamic characteristics are obtained, the improved advice of structural design for the subframe is proposed.

In this paper we propose a prototype of mobile car license plate recognition system for helping user identify car information on smartphone. The research presented here addresses special requirement and challenges in mobile application. The implementation of new architecture and system process flow with functions will help user real-time car image photograph, recognition and identification. We demonstrate the feasibility of this system by experimental results.

A large scale ingot was dissected to study the segregation law of the elements. The influence of composition segregation to the microstructure and mechanical properties of SA508-3 steel was studied by the comparison of three positions on the ingot. Two precipitated phases were approved to be alloyed cementite and molybdenum carbide (Mo2C). It has demonstrated that the middle and upper parts of the ingot were almost the same in compositions except for a slightly difference in the carbon content. The upper part with more carbon included has relatively more carbide precipitation after the performance heat treatment. The bottom part of the ingot has the lowest carbon and molybdenum content, while the reduction in the amount of precipitated carbide was not observed. On the contrary, fine needle-like Mo2C are extensively distributed in the matrix of the bottom part besides a variety of coarse cementite rods. And the data of Energy Dispersion Spectrum (EDS) mapping has suggested that precipitation of Mo2C tends to bring the segregation of impurities. Many large inclusions were found in the bottom part of the ingot, which were considered to be the main reason for the strength loss of this area.

The mesoporous molecular sieve MCM-41 was synthesized by hydrothermal synthesis method with iron ore tailings as starting material, and CTAB as appendage. The properties, kinetics and thermodynamics of Ni2+ from water adsorption process on MCM-41 residue were studied. The data demonstrated that the products possess typical properties of molecular sieve MCM-41, with specific surface area of 576 m2/ g, and the average pore size is 5.53 nm; the adsorption of MCM-41 residue to Ni2+ was decalescence reaction and the relationship between adsorbing capacity and equilibrium mass concentration is in accordance with the isothermal adsorption equations of Langmuir, and the removal rate of Ni2+ increases with the increasing of pH.