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Toxic data of local fishes was very essential in the derivation of local water quality criteria. In this study, two local fishes (S.dabryi and P.parva) of Liao River were chosen to conduct 96-h acute toxic data under ammonia (total ammonia) whose pollution was proved to be serious in Liao River. 96 h LC50s of S.dabryi and P.parva under total ammonia were 35.36 mg/L (pH=7.50, T=20.00°C) and 30.35 mg/L (pH=7.50, T=20.00°C), respectively. These toxic values could be used to supply the local database which was the basement to formulate site-specific water quality criteria accordingly in Liao River.

The Schiff base 4-methoxysalicylaldehyde thiosemicarbazone (MST) was synthesized and its corrosion inhibition effect on carbon steel in 0.5 M H2SO4 solution was tested via weight loss and electrochemical impedance spectroscopy (EIS) measurements. The results show that MST serves as an effective corrosion inhibitor for carbon steel. The corrosion rate of carbon steel decreases with the increase in concentration of MST. The adsorption of MST on the carbon steel surface conforms to the Langmuir adsorption isotherm.

In order to study the mechanical properties of recycled concrete small-sized hollow block, some recycled concrete small hollow blocks were tested separately for mechanical behaviors. Through experimental study, the density, moisture content, anti-permeability, dry shrinkage, compressive strength and bending strength of mechanical property parameters are derived. The results show that material performance indicators of the recycled concrete small-sized hollow block meet the stipulations of the code requirement.

On the foundation of discovery of the traditional incomplete information system, this paper introduces ontology semantic similarity to improve the traditional similarity relationship, and eliminate the inaccuracy of discovery of knowledge brought by partial transmission. Based on the original model, this paper proposes a more obscure similarity relationship under the improvement of incomplete information system. Furthermore, this paper also advocates a knowledge discovery algorithm based on the combination of weak similarity relationship and attribute value similarity, which not only considers the VPRS of existing null semantics based on the weak similarity relationship and attribute value similarity, but also explores and studies the knowledge discovery method of non-existing null incomplete information system.

In this study, water samples were collected randomly from water system of Beijing urban area and analysed by inductively coupled plasma-atomic emission spectrometry (ICP-AES) method to determine the contents of harmful heavy metals (Hg, Cd, Zn, Cu, Ni, Cr, Sb, As and Pb). The concentrations of detected heavy metals were found between detection limit of the instrument to 387.196 mg/L. Among them, one sample gave a very high concentration of copper element. In order to get rid of this copper ion away, a chelating type fiber was used to treat the water sample. After treatment with chelating fiber, the concentration of copper was lowered to -5mg/L.

This article based on Real measurement data of mine, then use Probability integration and Numerical Simulation that most commonly used methods in movement and deformation prediction to compute. By comparing the final sinking graph of the two methods and the actual data, to achieve the applicability and accuracy of two ways. The research have certain reference significance and revelatory effect on the selection of different methods of the surface subsidence prediction.

The interaction between n-alkanes and pour point depressants with different structures was investigated. Using n-hexadecane as the representative component of crude oil n-alkanes, molecular simulation was employed to study the interaction between polyacrylate pour point depressants with different side chain length and n-hexadecane, and the interaction between polyacrylate pour point depressants with different polar building blocks and n-hexadecane. It was shown that during wax precipitation process, the mixed energy is low when the side chain length of acrylate is compatible with n-hexadecane. It is easier for polyacrylate to go into wax-crystal lattice, thus lowering crude oil pour point. The simulation for pour point depressants consisting of acrylate and other different polar building blocks demonstrated that the stronger the polarity of polar building block, the lower the interaction energy between polymer pour point depressant and n-hexadecane. At the same time, it is easier for polymers with polar building blocks to interact with n-alkanes. The polar building block can effectively inhibit wax-crystal growth and thus improve crude oil low-temperature fluidity.

This paper presents a novel sub-pixel corner detection algorithm for camera calibration. In order to achieve high accuracy and robust performance, the pixel level candidate regions are firstly identified by Harris detector. Within these regions, the center of gravity (COG) method is used to gain sub-pixel corner detection. Instead of using the intensity value of the regions, we propose to use corner response function (CRF) as the distribution of the weights of COG. The results of camera calibration experiments show that the proposed algorithm is more accurate and robust than traditional COG sub-pixel corner detection methods.

The remanufacturing for the traditional idle relief grinding machine is introduced in this paper to overcome its shortcomings, such as low precision, low automation degree and poor flexibility. The drive system of the traditional relief grinding machine was renovated with ball-screws and servo-drive system Sinamics S120, the original control system was replaced by numerical control system Sinumerik 828D. After remanufacturing, the mechanical structure of the traditional relief grinding machine is simplified and the machining accuracy meets the requirements. The automation degree and the flexibility of the machine are enhanced, and the labor intensity of the workers is reduced.

In the present study, we researched the influence of storage time on quality of soy protein-celery composite paper. During the storage time, the protein content in the paper does not change significantly; Aerobic plate counts were decreased along with the increase of the storage time; Composite paper and celery paper color index values indicated that their value was related to the color yellowish-green (-2 to +2), except for celery paper in the 0 months; papers DPPH• radical scavenging rate sharply decreased, and was not detected till the third months.

Polylactide(PLA)-based wood plastic composites (WPCs) toughened with LLDPE were manufactured by extrusion blending followed by injection molding. The fracture surfaces created from the impact test were recorded with SEM. Fractal analysis has been used to calculate the fractal dimension of the fracture surfaces with four different techniques. Then, the relationship between the fractal dimension of the fracture surfaces and its impact strength of the PLA-based WPCs was investigated with the linear regression. The results show that there is a positive correlation between the impact strength and the fractal dimension for each calculation method.

A flask solvothermal method was firstly utilized to facile synthesize greigite Fe3S4micro-crystals (MCs). By using iron nitrate, element sulfur as raw materials as well as oleylamine as the solvent, high yield of Fe3S4MCs with hexahedron microstructure was obtained. In addition, it was found that it was easily to achieve transformation between Fe3S4and Fe7S8through changing reaction temperatures and iron-sulfur ratios. The several different morphologies of Fe3S4MCs were obtained by using other sulfur sources. The synthetic approach demonstrated here could be of great potential for the controlled synthesis of other metal chalcogenides.

The technology of strengthening RC beam with CFRP sheets is now a hotspot of research in civil engineering. The FEM analysis was made for the whole deformation course of the flexural behavior of RC beam with CFRP sheets on lateral side, and the result was coincided with the experimental results.

Based on electrical and chemical analysis in oils of some fault transformers in Shenzhen, it indicates that the corrosive sulfur contained in insulating oils may cause faults. Corrosive sulfur would react to copper wire and engender Cu2S during the operation of transformer. Because of the electric characteristic of Cu2S, this substance will penetrate and pollute insulating paper of the wire, and then weaken the insulation intensity. At last it would wear out coil insulation. Experiments indicate that adding passivator to insulating oil is an effective method to solve the problem. Passivator can form a protection layer on the surface of copper, which can avoid copper corrupting and can stop copper deposition in the presence of potentially corrosive sulfur compounds as well.

As the number of students who attend the arts exams has been growing, each admission institutions need to score the human head portraits of art sketch with the number of ten thousand and even 100 thousand. Thus it is an innovative research on how to conduct image recognition with the help of advanced computer technology. Image Recognition Technology is to give the computer the intelligence of human vision, so that the computer can quickly and accurately recognize the object on the input images. However, in the recognition process such factors as light, rotation and shield increase the difficulty of identifying the human head portrait images. In order to get better recognition performance, this paper studies the feature extraction of human head portrait based on SIFT (Scale Invariant Feature Transform). From the practical application, it can be seen that the approach proposed in this paper is feasible and is of good recognition performance.

With the ever-changing education information technology, it is a big problem for the universities and college that how to classify the thousands of copies of the image during the art examination marking process. This paper is to explore the application of artificial intelligence techniques, and to do accurate classification of a large number of images within a limited time and under the help of computer. It is can be seen that the proposed method is feasible through the application of the results of the actual work. Artificial neural network training Artificial neural network training methods have two mainly style, which are Incremental Training and Batch Training, and take the amount of different network training mission as the distinction standard. First, to introduce the Incremental Training [1], that means whenever the network receives the input vector and target vector, it have to adjust once the connection weights and thresholds. It is an online learning method. The other one is Batch Training [2], that means no longer adjust the connection and immediately, but perform bulk adjustment, and after a given volume of the input vector and target vector. Both training methods can be applied, whether it is static or dynamic neural network. Different results will be obtained by artificial neural network for the use of different training methods. When using artificial neural networks to solve specific problems, learning methods, training methods and artificial neural network function should be selected according to the expected results of question type and its specific requirements [3-4]. The selection of parameters of wavelet neural networks and adaptive learning

According to the characteristics of car seat structure and the distribution of car seat load, the finite element static strength model of the car seat is constructed in this paper. The model contains shell elements and beam elements. Some seat structure elements such as welding connection, screw connection, pin connection are simplified in the model. Simulation analysis of the static characteristics of car seat backrest frame model is carried out. At the same time, the experimental research on the static strength characteristics of the back seat is made by the measurements of non-electric physical quantities. By comparing and analyzing the results of experiment and computer simulation of seat static strength, the practicability and credibility of the seat static finite element analysis model and simplified model constructed in this paper are verified. It also proves that the simulation of various connecting forms of the seat structure is effective and is a reliable method in the structural design of the car seat. The model and simulation of the car seat can reduce the cost and shorten the design period.