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Microalgae have rich oil production under full photosynthesis, which reaches over 50 mass%. In addition, microalgae oil contains the prolific cis-4,7,10,13,16,19-docosahexaenoic acid (DHA) that is usually refined for making health food or food additives. This study investigated Aurantiochytrium sp., which is a kind of microalgae, the oil of which is also refined for use in health food or food additives. The solid byproducts of Aurantiochytrium sp. oil are more than 20 mass%, discarded as rubbish. Fortunately, the solid byproducts have been found to contain a large amount of palmitic acid that exceeds more than 67 mass%, but it is difficult to transesterify from the solid byproducts of Aurantiochytrium sp. oil, such as the waste cooking oil or waste engine oil, which contain many impurities. Therefore, the sequences of saponification, reduction reaction, and acid-catalyzed reactions were conducted for the full process of transesterification in this study. Overall, we have successfully obtained more than 92 mass% transesterification rate from the solid byproducts of Aurantiochytrium sp. oil. The solid byproducts are waste turned into gold.

Mercury is one of important trace heavy metal elements and about 1/3 of mercury in the air comes from emissions of coal-fired flue gas. In this study, we simulated mercury’s 4 important reactions of the oxidation kinetics mechanism and got every reactions’ rate variations; meanwhile we studied the kinetics of four reactions and got the reacting paths, five pre-exponential factor in different temperatures, reaction activation energy change and reaction rate constant change, a relatively comprehensive homogeneous oxidation model established. Through the above simulation study, the kinetics and thermodynamics parameters of 4 primitive reactions are obtained, having a great benefit for understanding the transformation mechanism of mercury in the process of coal combustion.

The fly ash at the exit of inlet and outlet of No.2 ESP and outlet of No.2 FGD in San-he Power Plant were sampled. The microstructure, elemental composition, particle size distribution and other physicochemical properties of the collected ash samples were tested and analyzed by a scanning electron microscope (SEM), X-ray energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and Mastersizer2000 laser particle size analyzer. The results showed that, ESP outlet fly ash particle size distribution curve was significantly moved to the left, the proportion of the fine ash at the outlet was significantly increased compared with that of at the inlet, the morphology and composition of ash at the outlet of ESP, FGD was significantly changed compared to the ash at the inlet of ESP, indicating that air pollution control equipment (APCDs) have a great impact on physicochemical properties and the fate of fly ash.

Precise load spectrum of crane is essential to its fatigue analysis and life assessment. The v-SVRM (v-support vector regression machine) correctly established is key to an undistorted load spectrum. Due to computational complexity, low accuracy, poor stability of the conventional model parameter selection method with v-SVRM, a fruit fly optimization algorithm with the characteristics of easy adjustment and high precision is applied. In order to make three kind parameters synchronously optimizing search, the fruit fly algorithm is improved in consideration of parameters characteristic of the crane load spectrum v-SVRM prediction model. Then, combining the improved fruit fly algorithm with penalty function and using anti-bound thought, a secondary optimization is carried out for three kind parameters. The results of examples engineering show that the optimal parameter group selected by the improved algorithm shortens the training time, reduces the computational complexity and improves the learning accuracy and generalization ability of v-SVRM model. The accuracy and stability of parameters is enhanced by secondary optimization, so as to a better robustness and versatility of v-SVRM predictive model. It also provides a new way for the establishment of efficient and convenient crane load spectrum v-SVRM forecast model.

Joining process and mechanical properties of clinched joints in Al5052 aluminum alloy sheets had been studied in this study. The clinched joints were classified to round one and rectangle one. Results of cross-section showed that the minimum thickness of the rectangle joints were lower than the round joints, and the aspect ratio of undercut section corresponding was larger. The strength of rectangular joint was 1.7 times of round one. Failure mode of rounded joint was the upper sheet fractures at the neck having a minimum thickness, but failure mode was the mix of neck-fracture and pulled-out for rectangular joint.

In this work, uniform mesoporous SnO2microspheres have been prepared via a facile and scalable method using tin tetrachloride pentahydrate (SnCl4·5H2O) and resorcinol-formaldehyde gel (RF gel) as starting materials. Furthermore, the structure and morphology of the as-prepared product were characterized by scanning electron microscope (SEM), Transmission electron microscope (TEM) and X-ray diffractometer (XRD). The results revealed that as-synthesized microspheres were around 500 nm in size and composed of large amount of SnO2nanoparticles with diameters of 10-20 nm. Gas sensors based on mesoporous SnO2microspheres were fabricated, and their gas sensing properties were tested for response to methane, butane, H2and CO gas. The sensor exhibited better sensitivity and selectivity to H2vapors at 300 °C than that of the conventional SnO2materials. The enhancement in gas sensing properties was attributed to their unique nanostructures.

The small-scale experiments of water mist extinguishing cardboard fire were carried out. Thermocouples and heat radiation sensor were used to measure the fire temperature and radiation heat flux of the burning area. The variation characteristics of the combustion field radiation heat flux under different spray pressure were studied. The results show that: the spray pressure has a significant influence on the extinguishing process. Based on the experiments, The simplified model of water mist absorbing heat radiation has been established, the results of this model agree well with the results of the experiments, and is good for predicting the effect of water mist particle diameter.

In this paper, a technology of ecological slope protection with aqueous polymer soil stabilizers is introduced. A clayey soil slope located in the Nanjing Pukou area in China is taken as a test field and a kind of aqueous polymer soil stabilizer, namely STW, are used. STW is developed by the research group of authors. The test field is divided into four regions based on the slope gradient, and one of regions, as a contrasting area, is no any soil stabilizer. The implementing process of this technology is also presented. The field test indicates that STW polymer soil stabilizer are very effective for improving the water-stability and anti-erosion of the soil slope and promoting the vegetation growth on the slope and is worth popularizing for water-soil prevention in the slope areas due to its simple implementation, low cost and ecological protection effect. Finally, the ecological slope protection mechanism of the aqueous polymer soil stabilizers is discussed.

Ethanol-based heat reflux extraction has been successfully applied in extracting isoflavone compounds from the dried root of Pueraria lobata (Willd.) Ohwi. The different extraction factors including ethanol concentration, extraction temperature, extraction time, ratio of solid/liquid and number of extraction cycles has been studied on the influence of the extraction yield of isoflavone compounds. And the orthogonal experiment has been used to optimize the extracting conditions. A variety of indicators were employed to evaluate the extraction efficiency, including the yield of puerarin, daidzein and total isoflavone. The optimal extraction technology was as follows: extraction temperature 90°C, ratio of solid/liquid 1:6, ethanol concentration 90% and extraction 2 h. Under the optimal conditions extraction rates of puerarin, daidzein and total isoflavone were 37.51±0.64 mg/g, 2.63±0.03 mg/g and 117.4±0.89 mg/g. The study of this article can provide theoretical basis for large-scale production of puerarin, daidzein and total isoflavone.

The Apocynum venetum L. of Apocynaceae plant is a traditional Chinese herbal medicine. In this paper, we analyzed qualitatively the active compounds in the aqueous extract from the leaves of Apocynum venetum L. by HPLCMS and HPLCDAD. The aqueous extracts method of the mainly active compounds from dried leaves of Apocynum venetum L. was based on HPLC/DAD coupled to an electrospray ionization (ESI) interface. Overall, 8 constituents were separated and identified, which belong to flavonoids.

With the medium of triethanolamine acetate ionic liquids and the help of cavitation effect of ultrasonic resonance, the TiO2 collosol is prepared by the sol-gel method and being loaded on nickel foam. The TiO2 electrodes are formed by calcinating at the high temperature. The results show that the optimal electrodes can be obtained with the medium of triethanolamine acetate ionic liquids, under the condition of high power ultrasound resonance for 15 minutes, the ionic liquid volume of 3 mL and the calcination temperature of 400 °C. After the wastewater is processed by photoelectric catalysis under the conditions of electrolysis voltage of 12V, electrode spacing of 1 cm, wastewater pH of 4 and illumination time of 90 minutes, the COD removal rate can reach 63.5%, while the decolorization rate can reach 93.6%.

With respect to serious water waste and backward cleaning devices relevant to the cleaning of road greenbelts, this paper describes an independently-designed water-saving greenbelt cleaning device with performance of energy saving and emission reduction. After the device is developed, relevant cleaning experiments are conducted on the gardening vehicles. The results show that the new water-saving greenbelt cleaning device can improve the efficiency of water utilization significantly.

With the number of applications increased in wireless mesh networks (WMNs), insufficient service capability is becoming a main obstacle. Meanwhile, cloud computing is an effective approach for organizing computing resource which can improve service capability remarkably. In this paper, framework of WMNs with cloud computing is proposed. Service capability of WMNs with cloud computing is judged and scored from 6 dimensions to make a composite comparison, which is shown cloud computing will be a promising approach for improving service capability in WMNs.

The intelligent information retrieval model discussed in this paper is constructed by multi-agent. Currently, BDI cognitive theory is accepted widely by the scholars of this field, but the related researches mainly focus on the theoretical derivation and presentation of symbols, lack of model facing practical application. In this article, a dynamic rule-based reasoning model is proposed. The model based on BDI theory is an expression of agent intelligence. The basic logical reasoning of the BDI theory is extended in this article. The author not only introduces several functions to study the dynamic changes of agents mental state, but also give a detailed description of how to use the theory of production rules to express BDI-based reasoning. This article also studies and designs the agent communication mechanism in MAS. Finally, the intelligent information retrieval system is designed and implemented with the idea of AOP.

Polycrystalline mercuric iodide films are being developed as a new detector technology for digital X-ray imaging. The properties of the contact between electrode and film play an important role in the performance of the polycrystalline mercuric iodide detector. In this paper, the films were grown on the thin film transistor (TFT) substrates via hot-wall physical vapor deposition method. Au front contacts were deposited onto the HgI2 films by thermal evaporation under a vacuum of 10-4Pa. The HgI2 films were characterized by X-ray diffraction (XRD). The surface morphology of the films before and after the process of evaporating Au was compared by scan electron microscopes (SEM). And the I-V curve was measured after evaporating Au electrode. The results indicate that the polycrystalline mercuric iodide films we prepared have a very strong (001) growth-preference. Au was deposited on the grain surface forming excellent ohmic contact with polycrystalline α-HgI2 film which was also confirmed by the I-V characteristic of HgI2 film after the process of evaporating Au electrode.

Low density polyethylene (LDPE) was modified by the addition of commercial fire retardants FR01 and aluminium hydroxide (ATH). ATH/FR01/LDPE composites were prepared by melt blending and extrusion in a twin-screw extruder. ATH was first modified by a silane coupling agent KH550 then added to LDPE. The flame retardancy, electrical property and thermal behavior of the LDPE composites were investigated by limiting oxygen index (LOI), volume resistivity and thermogravimetric analysis (TGA), respectively. The results indicated that the surface modification of ATH (M-ATH) could greatly improve the dispersibility and compatibility with LDPE matrix. The mechanical property tests showed good mechanical properties of composite, compared with unmodified one, tensile strength and elongation of M-ATH/LDPE were all improved, and the addition of FR01 improved the flame retardancy of ATH/LDPE remarkably. TGA results demonstrate that char yield of M-ATH/FR01/LDPE (30/15/70) reaches 27 wt% at 600 °C in Ar atmosphere.

In order to study the electrical ignition method of liquid propellant spray, two experimental devices of liquid propellant spray and alternating current (AC) pulse discharge were designed. By using of high speed digital camera system, the test on electrical ignition of HAN-based liquid propellant LP1846 spray were carried out under different injection pressures. The results show that under 50W AC pulse discharge conditions, LP1846 droplet cluster, with the mean diameter in the range of 20~40μm, can be ignited reliably. Based on above experiments, a simplified model of ignition delay time of LP1846 single droplet was set up, the calculation value is well matched with the experimental data.

The dyeing wastewater is processed by photoelectric catalytic oxidation with nickel foam electrode of titanium dioxide， which is prepared with ion liquid. The main influence factors including electrode distance, electrolysis voltage, pH and electrolytic time were studied in processing waste. Results show the optimal operating condition is the electrode gap of 1.0 cm, pH value of 4.4, electrolysis voltage of 5.0V and 100 mg∙L-1 dosages of Na2SO4 in 120 minutes electrolysis time under the irradiation of ultraviolet light . The effect of processing the wastewater with catalytic electrolysis can be greatly improved in water cycle system with continuous air, flocculent and activated carbon. Consequently the removal rate of the Chemical Oxygen Demand (COD)is 78.69%, and the decolored rate is 97.02%. The COD of the processed wastewater is within 100.0 mg∙L-1, and meets the first national emission standards. It is expected that the method will have good prospect in protecting the water resources and environment.

This study reached a gold ore which contain 3.83g/t gold, to investigate the available gold recover methods, direct cyanide leaching test and “biooxidation-cyanide” leaching process were utilized after enrich gold by flotation. When regrinding the flotation concentrate to 95% -325mm, the leaching rate of “biooxidation-cyanide” leaching reached 94.47%, compare with direct leaching, the leaching rate increased almost 67%. Obviously bacterium oxidation is a useful pretreatment for gold leaching.

This paper addresses geometry design of a new kind of 2-DOF five-bar parallel manipulator actuated by two orthogonal layout linear actuators. Although the manipulator has only one geometric parameter, i.e., the link length, the distribution of performance index is more complex. Here, we propose a design approach utilizing a performance chart and local condition index. The key problem in the design of the manipulator is the determination of not the link length but the workspace satisfying the design index. This paper gives an effective method to obtain the basic good-condition workspace without dimension. Then, based on the optimum non-dimensional result, the optimum dimensional parameters are achieved which is suitable for the desired workspace. The optimum methodology of this paper is convenient and can be extended to other parallel manipulators

In this paper, a planar five-bar mechanism driven by two orthogonal layout actuators is proposed. The inverse and forward kinematics can be described in closed form. The Jacobi matrix, singularity and workspace of the mechanism are investigated. In addition, charts of some performance indices, such as dexterity, velocity, payload capability and stiffness index, are plotted. The results show that the mechanism has a flatter singularity-free workspace, which is usually our research object. On the other hand, Dexterity, Payload capability and stiffness index of the mechanism are basically the same distribution on the workspace, which are axis symmetric. But, the trend of velocity index is opposite. The proposed mechanism can be applied to the field of machine tools or used as the mobile base for a spatial manipulator. The results of the paper are very useful for the design and application of the new mechanism

Based on the experimental study of normal-section bearing capacity of four steel reinforced high-strength concrete (SRHC) L-shape short pier shear walls with two-way eccentric compressive load, this thesis discussed the failure pattern and working mechanism and get some general laws about normal-section baring capacity of this kind of specimens. The research results show that: the failure pattern of SRHC L-shape short pier shear wall with two-way eccentric compressive load is classified into two types-large eccentric compression and small eccentric compression; the sectional strain basically fit the plane-section assumption; steel and concrete can practically work cooperatively until the specimens are damaged and the steel of compressive region yielded; the normal section baring properties of the perforated frame member and the trussed frame member were fairly close to each other and the trussed frame has no advantage compared with the perforated one.

Combining the mechanism of the hash chain with the forward-secure proxy blind signature, we firstly propose a new strong forward-secure proxy blind signature scheme. This scheme has many secure characters, such as strong forward security, namely, although the attacker get the key in some period , the attacker cannot forge the signature in the past and future periods, verifiability, unforgeability, distinguishability, identifiability, strong blindness.

To assess the roller coaster multi-body system security, it is need to extract the running process of kinematics, dynamics, load spectrum and other features, as basis dates of the roller coaster structural design. Based on Solidworks/motion software and in the 3D model, the calculation formula of the carrying car velocity and acceleration is derived, and the five risk points of the roller coaster track section are found by simulation in the running, and the simulation results of roller coaster axle mass center velocity are compared with theoretical calculation results, which error is less than 4.1%, indicating that the calculation and simulation have a good fit and providing the evidence for the roller coaster structure design analysis.

The synthesis of (S)-1-benzyl-3-pyrrolidinol is described. Starting from L-malic acid and benzylamine, we improved the synthesis of (S)-1-benzyl-3-hydroxypyrrolidine-2, 5-dione via melting reaction, without using any solvent. Followed by reduction with sodium borohydride-iodine in tetrahydrofuran, we synthesized the target compound. We used IR spectra to study the process of the reduction and modified the reaction conditions. It is the first time we reported (S)-1-benzyl-3-pyrrolidinol-borane which is the intermediate of the reduction with sodium borohydride-iodine system, and its spectral data (IR, 1H NMR, 11B NMR, MS spectroscopy).

Strontium ferrite micro- and nanofibers have been prepared by the sol-gel process and the electrospinning with diameters about 1 μm and 100 nm, respectively. Single phase strontium ferrite fibers are formed after calcined at 750 °C for 2 hours for both the sol-gel and electrospinning processes. These strontium ferrite fibers are fabricated of nanosized particles with a hexagonal plate-like morphology, which grow with the calcination temperature. The microfiber cross-section contains multi-nanoparticles whilst the nanofiber with a necklace-like morphology is linked by nanoparticles at the calcination temperature range from 850 to 1050 °C. The magnetic properties of strontium ferrite fibers are mainly influenced by the grain size and fiber diameter. Both the strontium ferrite micro- and nanofibers calcined at 900°C for 2 hours are fabricated from single-domain grains around 56 nm and exhibit the specific saturation magnetization of 60.8 A•m2•kg-1 (microfibers) and 59.9 A•m2•kg-1 (nanofibers) and coercivity of 361.9 kA•m-1 (micronfibers) and 523.6 kA•m-1 (nanofibers). The coercivity difference between the micro- and nanofibers can be attributed to the different shape anisotropy energies arising from various magnetization reversal behaviors for the micro- and nanofibers.

A new method, obtaining the pressure-time relations during air inflation and deflation process, is proposed to research the dynamic characteristic of a pneumatic solenoid valve. The current, magnetism, mechanical and air subsystems of the valve are investigated. In order to experimentally verify the advantage of the new model, two models are compared. Simulation results show, the opening and closing reversal times of the model without air subsystem are 29.6ms and 30.7ms. The new model’s reversal times are 31.8ms and 36.1ms. 32.5ms and 35.3ms are the results by experiments. The experimental results show very good agreement with the new model.

Bioelectrical impedance measurement is a widely used biomedical detecting technology. However, most traditional bioelectrical impedance measurement devices are bulky, expensive and lack of flexibility. In order to reduce costs, increase flexibility and maintain similar performance, a portable bioelectrical impedance measurement system was designed in this paper. The measurement front, with an ARM based microcontroller and integrated impedance converter chip as its core device, communicated with the host computer via USB bus. Based on the four-electrode technique, DFT digital demodulation and software calibration and compensation algorithm, the system realized its functions. Experimental results indicate that the system can achieve high precision bioelectrical impedance measurement. With the advantage of high integration and low-cost, the system can be widely used in household healthcare, clinics and biomedical research and testing.

The classifier, built from a highly-skewed class distribution data set, generally predicts an unknown sample as the majority class much more frequently than the minority class. This is due to the fact that the aim of classifier is designed to get the highest classification accuracy. We compare three classification methods dealing with the data sets in which class distribution is imbalanced and has non-uniform misclassification cost, namely cost-sensitive learning method whose misclassification cost is embedded in the algorithm, over-sampling method and under-sampling method. In this paper, we compare these three methods to determine which one will produce the best overall classification under any circumstance. We have the following conclusion: 1. Cost-sensitive learning is suitable for the classification of imbalanced dataset. It outperforms sampling methods overall, and is more stable than sampling methods except the condition that data set is quite small. 2. If the dataset is highly skewed or quite small, over-sampling methods may be better.

In this paper, it is proposed a new method of free-from surface’s reverse engineering, making data acquisition and surface reconstruction form closed loop system, solving no feedback problems in the measuring and modeling process, shortening the time of the whole reverse engineering, improving the quality of reconstructed models. The core of this paper is used the CMM adaptive measuring method and non-uniform b-spline surface reconstruction method, integrating the free-from surface measuring and modeling in a closed loop system, realizing the CMM real-time online measurement and reconstructed surface real-time update.

Aiming at security problem of metal structure of overhead traveling crane, the accident tree is established based on Accident Tree Analysis to further study. The solution of minimizing cut sets and least path sets are obtained by accident tree calculating. Finally several possible measures to prevent structural faults are obtained through final results of the calculation analysis.

Convex hull is a very important data structure of computational geometry design. This paper presents an algorithm to construct the convex hull of a set of scattered points by coordinates and relative angle method. The algorithm determines the convex vertexes and eliminates some non-convex vertexes, which greatly reduces the searching scope and the complexity. Delaunay triangulation is widely used in 3D surface reconstruction. Due to its duality, Delaunay triangulation is usually constructed through Voronoi diagram. Delaunay triangulation is directly constructed in this paper. The algorithm is simple, stable and easy to implement, especially for less data points.