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In the region where Eastern Ningxia coalfield locates, with the fragile eco-environment and the relative short water resources, it is significant to make clear the influence of coal mining on the groundwater in this region. According to analyses of water-filling factors for the 21 mine fields in the 7 mining areas and 1 independent mine field of Eastern Ningxia coalfield. Firstly, this paper selects the formula in the regulations on the preserving of the coal pillar and coal mining under buildings, water, rail and main shafts (regulations for short) and the Standard on the Exploration of Hydrogeology and Engineering-Geology in the Mining Area (GB12719-91) (standard for short) to calculate the height of water-flow fractured zone in the first coal seam mining, and compares the analysis results of the above formula to the observation data of 3 working faces, and determine the estimated method on the height of water-flow fractured zone, and then use “three maps-two predictions” method to complete the criterion of aquifer water-enrichment and inbreak in safety of the first coal seam. Finally, analyzing the influence of coal mining on the direction of groundwater and recharge-runoff-discharge conditions, the final comprehensive division program on the risk of the groundwater inrush is presented. The research results served as the general guidelines for the mine operations.

By analysis the difference of applying the rough set method and the neural network method to pattern recognition, a improved recognition method that the rough set method is the front system of neural network was produced. the advantages of this method is that the knowledge representation system is reduced without affecting the recognition precision, so the complexity of neural network system and the time of calculating the attribute value is declined ; at the same time ,the neural network as the postpositional system has the tolerance and anti-jamming capability, but it is difficult to do this with rough set method. The example about how to combine these two methods and conclusions from this combination was given.

In this paper, phase equilibrium of Li+, Mg2+∥Cl-, SiO32--H2O system at 220°C was researched. The solid phases were characterized by X-ray diffraction (XRD). Lithium silicate, hectorite, karpinskite and magnesium hydroxide were observed as solid phases. According to the analysis of XRD, the phase diagram was obtained. The phase diagram could be used as the theoretical principle for synthesis of hectorite.

Dichloromethane (CH2Cl2) is one of main components of odorous gases from pharmaceutical sewage treatment plants. In this work, firstly the CdS/TiO2 loaded on ACFs composite photocatalysts was prepared. Gaseous CH2Cl2 was selected as the model reactant, the photocatalytic activities of CdS/TiO2/ACFs composites had been investigated. The results showed that the degradation rate of CH2Cl2, when the light was turned on after the CdS/TiO2/ACFs composites were saturated, was significantly higher and could maintain a longer time than that one of direct light. At initial stage, the degradation rate of CH2Cl2 could reach to 94%, while it decreased with the increase of the irradiation distance. It increased with the amount of composites before illumination 70 min; however it becomes reverse after 70 min. The degradation rate of CH2Cl2 decreases with the inlet concentration, when the inlet concentration was 26.5 mg m-3, the photodegradation rate declined about 70 % than that one of 8.5 mg m-3 when light 30 min.

Rod-like SBA-15 mesoporous materials were synthesized and modified using two-step process through aminopropyl and glutaraldehyde. Aminopropyl was first covalently bonded to silanol groups present on the surface of mesoporous silica. Successively, the reaction of aldehyde with aminopropyl was followed. Immobilizations of Porcine pancreatic lipase (PPL) onto functionalized SBA-15 (NH2-SBA-15-PPL and G-SBA-15-PPL) have been achieved. Relative activities and reusability of NH2-SBA-15-PPL and G-SBA-15-PPL for triacetin hydrolysis have been studied.

The cone index is one of the important indicators that can describe the comprehensive physical characteristics of lunar regolith. Its closely related to the sink and sideslip of lunar rover and also has widely used in prediction the trafficability, adhesion property, tractive performance of lunar rover. Based on component method, a kind of low gravity simulator, the tiltable test-bed has been built. This study has got the stable low gravity along axial direction and measured the penetration resistance characteristics of JLU-2 in different gravity through tests. The results shows that the gravity environment has an obvious impact on the cone index of lunar soil simulant, CI values reduce with the decreasing of gravity environment. Namely, in the low gravity condition, it shows weaker resistance ability for a foreign object to penetrate into. The result has important application value of prepare, optimize and risk assessment in walking mechanism of lunar rover and the sampling mechanism.

Magnetic Fe3O4 nanobubbles surrounded by nanoparticles are prepared by adopting microwave assisted reflux method. The nanomagnetic particles surrounded by small beads like particles are fabricated by irradiating the prepaperd sample solutions by microwave radiations coupled with reflux method simultaneously at 90°C for 45 mins. The characterization of the prepared Fe3O4 particles are carried out by using x ray diffraction, scanning electron microscopy and transmission electron microscopy. The instrumentations shows the morphology that is thick walled bubble like with approximate diameter of about 300 nm to 400 nm surrounded by small nanoparticles of 5 nm to 30 nm in range. The particles are bubbles like and some broken bubbles showed that these might be hollow from inside.

Acid stability of Bacillus licheniformis alpha amylase (BLA) was improved by error-prone polymerase chain reaction. The mutated BLA gene was expressed in Escherichia coli. An acid stability double mutant (K344R/H405R in BLA) was isolated. Two single mutants K344R and H405R were obtained by the way of site-directed mutagenesis. The enzymes (BLA) of the three mutants were isolated and characterized. Kinetic studies showed that the kcat/Km values of the mutants K344R, H405R, and K344R/H405R under pH 4.5 were about 8-, 11.5-, and 17.7-times higher than that of the wild type enzyme. As revealed by the structure models of the wild-type and mutant enzymes, the amino acids substituted of R344 and R405 in the BLA contribute to its acid stability.

Heat flux distribution has an important influence on grinding thermal field, therefore an accurate heat flux distribution model must be established in order to precisely simulate the grinding process. A new heat flux distribution model was developed by theoretical derivation in this paper. In order to simulate the transient grinding thermal field, finite element models were created, applied with the new, uniform and triangular heat flux models respectively. Comparisons between the distributions of temperatures and temperature histories calculated from numerical simulations using the three different models were also made in this paper.

Machine learning uses experience to improve its performance. Using Machine Learing, to locate the nodes in wireless sensor network. The basic idea is that: the network area is divided into several equal portions of small grids, each gird represents a certain class of Machine Learning algorithm. After Machine Learning algorithm has learnt the parameters using the known beacon nodes, it can classify the unknown nodes location classes, and further determine their coordinates. For the SVM OneAgainstOne Location Algorithm, the results of simulation show that it has a high localization accuracy and a better tolerance for the ranging error, while it doesnt require a high beacon node ratio. For the SVM Decision Tree Location Algorithm, the results show that this algorithm is not affected seriously by coverage holes, it is suitable for the network environment of nonuniformity distribution or existing coverage holes.

Wireless sensor node's localization is a funda-mental technology in Wireless Sensor Networks. There are only quite a few study on three-dimensional (3D) localization which is suffered in slow progress, actually, is one of the main difficulties in WSN localization. Based on the study of the existing two-dimensional positioning algorithm and the application of terrain modeling, localization algorithm for sensor nodes in (3D) condition has been focus on as well as the application of terrain model. Using the idea proposed by representative algorithm--APS multi-hop AOA (Angle of Arrival), this paper proposed a new algorithm named Multi-hop Three Dimensional AOA With Space-based Angle Trans-mission (MSAT3D AOA). Using this technology, target nodes can use information of anchor nodes which are more than one hop away form. This paper also combined MSAT3D AOA algorithm with Delaunay triangulation algorithm for terrain modeling.

Through using the ICEM CFD software , we make a model and mesh division to one of the aspiration drum precision seeding mechanisms negative pressure chamber. And we reuse software ANSYS FLUENT to make simulation analysis of the negative pressure chamber for flow field . The conclusion reflects the distributor in the suction of air distribution in the process of the situation correctly. That provides references for distributor structure optimization design, and provides the guidance for experiment so as to save manpower, material resources and the time.

Zinc oxide with spherical shaped and flower shaped morphology are prepared by simple one step solvothermal method. The product is subjected to characterization to investigate the morphology and size by using X ray diffraction , semi electron microscopy and transmission electron microscopy. The size of the prepared zinc oxide particle is in the range of 1 micrometer to 3 micrometers. The outer surface of the particles is not smooth but it is rough. The possible formation mechanism for the product is investigated that is further justified by means of structural characterization.

Quick-frozen oat dumplings were produced by adding some Oat flour in dumpling wrapper. The effect of oat flour ratio on the optimal amount of water of the bland flour, cracking ratio and edible quality of quick-frozen oat dumpling were researched. The optimal amount of water of per gram Xiang Man Yuan dumpling flour and oat flour are 0.43g and 0.63g individually. The cracking ratio of products increases with the increases of oat flour ratio. The effect of oat flour ratio on the sensory evaluation and the outward appearance score of quick-frozen oat dumplings is very significant in 1‰ level, their correlation coefficient are 0.990 and 0.994 respectively, and the regression model equations are as follows: Y=90.094－112.477X; Y=18.519－21.763X.

In the new century, the new technology and new knowledge is faced to the world that has been developing fast. Based on the result of widely investigating and collecting data, we have a new understanding to the industry of natural monopoly. The modern engineering education of Material Forming and Control Engineering Major has seen great reforms,and progress in research achievements in educational thoughts, training program, curriculum and practice teaching in this paper.

It is an effective method to solve the contradiction between power supply and demand by using battery energy storage power station to adjust the load to keep balance. The kind and capacity of storage battery were selected based on its current application. Compared with multiple storage battery series-parallel connect modes, the paper proposed a connection mode using the combination of series and parallel. Designed a storage battery charge and discharge control system based on SVPWM technology, which includes hardware circuit and software design. Simulated the system through MATLAB and analyzed the wave shape, it proves that the circuit topology structure is validity and have a reliable control effect, and the energy storage power station achieves better load shifting effect on the power balance.

The austenite 1Cr18Ni9Ti stainless steel is one of difficult-to-cut materials. It has poor dilling process, especially for micro-hole machining. The main reasons are the tiny drill, poor rigidity, easy to deviation. Moreover, the chip is difficult to discharge, so the drilling force is increased and the drill bit is easy to break, or even it is impossible for micro-hole drilling. In this paper, the vibration drilling process is adopted. The vibration drilling 1Cr18Ni9Ti stainless steel micro-hole process mechanism is researched. The stainless steel micro-hole drilling experiments are conducted. The results show that the vibration drilling can be a better solution for 1Cr18Ni9Ti stainless steel micro-hole processing.

In this paper, a novel method for pulse integration in radar-probing system is proposed to yield a low sidelobe response. According to m-sequence widely used in spread spectrum communication system, a bipolar pulse sequence is designed in this paper. At the receiving end, the envelop-detected signal is processed by a corresponding algorithm which dilutes the range sidelobe influence much. Because of the good autocorrelation and cross-correlation properties, waveforms yield a low sidelobe response and major lobe to side lobe ratio can reach 30dB or more, which is easy to satisfy the practical requirements. Simulation results show the good performance of the proposed approach. Furthermore, the approach is compatible to the conventional radars and can also be applied to the upgrade of radar.

In this paper, phase equilibrium of MgCl2-LiCl-Na2SiO3-H2O system at 180°C was researched. The solid phases were characterized by X-ray diffraction (XRD). Lithium silicate, hectorite, karpinskite and magnesium hydroxide were observed as solid phases. According to the analysis of XRD, the phase diagram was obtained. The phase diagram could be used as the theoretical principle for synthesis of hectorite and comprehensive utilization of concentrated natural brine.

The effect of particle size on the water-soluble substances and microscopic structure of sorghum straw powder were investigated. Sorghum straw powder with four particle size (300 ~ 450μm, 125 ~ 150μm, 97 ~ 105μm, 330 ~ 420nm ) were studied for analysing changes of water-soluble substances and microscopic structure. The results showed that with the particle size decreasing the pH value of water-soluble substances decreased, the concentration of reducing sugar in water increased firstly then began to decrease when it reached to a certain value, the crystallinity of sorghum straw powder decreased, and the degree of polymerization of sorghum straw was lowered ,respectively.

This paper used respective ratios of 50%, 60%, 70%, 80%, 90% and 100% of straw and pig excrement as raw materials to produce biogas and fertilizer. The test focused on gas production, the contents of available nutritional elements nitrogen, phosphorus and potassium, and the organic matter content. The experimental results demonstrate the fermentation can produce more biogas, nitrogen, phosphorus, potassium, and organic mass under the conditions which the fermentation cycle is 15 days and the ratio of straw and excrement is 70%.

Using special culture medium, dominant photosynthetic bacterias were enriched from sewage silt and paddy fields with plentiful light and organic compounds. Five strains of photosynthetic bacteria capable of producing hydrogen were purified and isolated by gradual dilution and double—deck solid medium. The analysis of the gene sequence information of 1 6SrDNA was carried out, and the five strains were identified as Rhodospirillum rubrum,R.capsulata, R.pulastris, Rhodobacter capsulatus, Rhodobacter capsulatus . Moreover, it was found that with Optimized medium formula, hydrogen production can be achieved 204h, the maximum hydrogen production capacity of 3.41L, the maximum hydrogen production rate was 44.17ml / (L • h),the highest hydrogen content of 46.73%.

The effect of Ca on the microstructure and corrosion properties was investigated. Vacuum induce melting was used to obtain the Mg-xCa-4Zn (wt.%) (x = 0%, 1%, 2% and 3%) alloys. Erode test was carried out in the Hank’s simulated body fluid for the alloys and the increasing of weight is carefully measured. The microstructure of the alloys was observed with optical microscope and energy spectrum analysis was used for accurate composition. It is found that as the increasing of Ca, the corrosion extent is getting serious for the Mg-xCa-4Zn alloys. Hardness increases as the adding of Ca in the alloys.

The composite samples using flint clay, andalusite and silicon carbide as starting material are made from the proportion of 35:60:5, 45:50:5, 55:40:5, 65:30:5 respectively. The samples are sintered at 1200°C,1300°C,1400°C,1450°C and 1500°C holding 4hrs separately. Both microstructure and mechanism of oxidation were analyzed by XRD and SEM. The results show that the samples have good resistance against oxidization below 1500°C, only the sample of fourth formula perform excellent and have the thinnest oxidation layer between all the formulas at 1500°C.

The nonlinear contact mathematic model is constructed for the bolt joint structure on the fixed end of the Gelin column of die casting machinery and the FEM model and optimization mathematic model for the bolt joint structure are realized by software of ANSYS and the APDL language embedded in it. The structural parameters of different type of thread in Gelin column are optimized. After the comparison of equivalent contact stress in the region of the different type of the bolt joint in Gelin column, it is shown that there is more even load-bearing characteristics with the trapezoidal thread than zigzag thread and the maximum of the equivalent contact stress with the trapezoidal thread is decreased about 41% of that in zigzag thread which can effectively improve lifecycle and anti-fatigue performance of the threaded joint in the gelin column.

The periclase-hercynite brick performance after different re-firing cycles was researched under different atmosphere. The results are shown that under the oxidizing atmosphere, the brick after re-firing would lead to the mutual diffusion of iron ions in both magnesium substrate and hercynite particles, which would further lead to ring cracks around hercynite. After the brick was re-firing at CO atmosphere, the mutual diffusion of magnesium and iron ions was even more severe, which formed magnitude of magnesia-hercynites and magnalium spinels. SEM results are shown that the porous structure around the hercynite could damage more severe.

Through dynamics test and theoretical analysis about rubber bearings in Auto body’s sub-frame, and the past research results of sinusoidal excitation, a hysteretic non-linear mathematical model of the rubber bearings is established under the condition of random excitation. The model shows that the hysteretic renewed force of the rubber bearings under random excitation can be expressed with the mean value and variance of random excitation’s statistical characteristics and speed. Finally curves of the hysteretic renewed force - displacement are reconstructed with the model built, which match the test’s results well.

Small motions will result in heavy influence to the production in high-speed paper machine, therefore, decoupling control is necessary. This passage Puts forward the opposite angles strategies to solve the function of decoupling aiming at solving the difficulty that occurs in practice, like the characteristic of hard-coupling and non-linear. According to the mathematics model of the flow box, decoupling the quantity of the two couplings in the processes. Meanwhile, Introduces the SIEMENS S7-300 PLC and the DCS system that is realized by the it.

This article states the principle and design method of load distribution, discussing the problems and solutions in the process of designing load distribution; the description about the importance of designing load distribution in the paper machine transmission system provides a theoretical proof to avoid uneven load distribution. And in this paper, the application of ACS800’s DTC inverter in load distribution of 2640/500 three fleeting multi-cylinder paper machine is introduced. The inverter’s communication, automatic interlock and parameter’ setting are presented. The application in practice proves that the result is effective. Meanwhile the attentive matters in practice are also provided.

Piston ring is one of the most important sealing components that can be easily damaged in reciprocating compressors. The severe non-uniformity of the pressure distribution was suggested to be the essential reason for the premature failure of the piston rings. Therefore, a test rig was set up to measure the pressure distributions as well as the build-up of the dynamic pressure difference, which could reveal the root cause for the non-uniformity of the pressure distributions. The results showed that the build-ups of the pressure differences between different rings were not simultaneous; there existed a threshold pressure, and the latter ring could work only when the pressure before the former ring reached to the threshold value. The pressure distributions were also investigated at the start-up and shut-down of the compressor, which further validated the cause of the premature failure of the first ring.

Power plants that emit great amounts of nitrogen oxides are the key total mass control part of the “Twelfth Five-Year Plan”. SCR is widely used because the technology is mature and the denitrification efficiency is high. According to the problems of the application of SCR, this paper puts forward relevant suggestions: 1) Combine different flue gas denitrification technologies to raise the denitrification efficiency. 2) Urea is recommended as the reductant considering the safety factors. 3) Issue relevant policies and strictly control the emission of sulfur trioxide.

In this paper, certain investigations were performed in the following aspects: analysis of optical emission spectra which is used for the identification of ˙OH, ˙H, ˙O, H2O2and O3on the inactivation of algae by observing the gas and liquid phase compositions, the optimal parameters such as treatment time, pulse peak voltage, and pulse frequency. Each experiment was carried out by introducing two difference gases, oxygen or air, separately above the liquid in the reactor. The results showed that the inactivation rate of algae reached 100% in the case of oxygen bubbling into the Chlorella spp. contaminated water for 7 min and the Chrysophyta spp. for 5 min. It took much longer time in the case of air bubbling that took 10 min for Chlorella spp. and 7 min for Chrysophyta spp.

The phase equilibrium of the LiCl-MgCl2-Na2­SiO3-H2O (LMNH) quaternary system at 150°C was studied and the phase diagram of the system was plotted, in order to synthesize hectorite with the nature brine, which was rich in lithium and magnesium. The solid phases were characterized by X-ray diffraction (XRD) and Energy Dispersive Spectrometer (EDS). It was found that hectorite, lithium silicate, karpinskite and brucite can be formed in this system.

The current research in access control is analyzed, and the features of access control in collaborative design systems are discussed. According to the new requirements of the access control technology in collaborative design systems, the attribute-based access control (ABAC) model is improved to a new one: supporting role and task ABAC model. The concept of role entity and task entity is introduced into the ABAC model. The formal definition and object model of the improved model are given, and the features of the newly-introduced model elements are discussed.

High-strength and micropore lightweight bauxite aggregate was fabricated by low grade raw bauxite powder, aluminium hydroxide powder and organic polymer (OP). OP was used as consolidator, binder and pore former and aluminium hydroxide was used as pore former. The influence of OP and aluminium hydroxide content on the property of the samples was studied. The phase composition and the microstructure of the sintered samples were characterized by XRD, SEM and the pore size distribution was measured by mercury porosimety. The results demonstrate that the bulk density of the samples decreases linearly and the apparent porosity of the samples increases gradually with the addition of OP. The lowest density reached 1.13g/cm3when adding 35% OP and 10% Al(OH)3. The average pore size is around 5μm, and increases with the addition of OP increased. The XRD showed the main phase of the sample is mullite and some little amount of corundum.

Engineering education has been a worldwide hot topic currently. Reform of engineering education call for a new model of cultivating talents. To the aim of training students’ engineering awareness, engineering skills and engineering spirit, combination general education and professional education, reference ISO9000 standards and according to engineering practice established eight principles of engineering education. University or college should be a place which guide and encourage students to study independently, multi-disciplinary and interdisciplinary learning. Respect the differences of students and teach them in accordance with individual differences. Curriculum setting should reflect the essence of ISO9000 management theory. Teaching practice show that TSIP (Try-Study-Instruct-Practice) teaching model is an effective method in engineering education and good results have been achieved. ISO9000 management theory and the TSIP teaching methods are applied in engineering education, could construct a model maximum meet the international CDIO standard engineering education. The learning process is teacher guidance and student-centered, teacher-student bilateral exchanges, practicality and self-study ability. This paper put forth a new way and a new model inventively for engineering education.

The optimal conditions of production of biopolymer by the culture of Pseudomonas fluorescens were examined, using brewery wastewater to replace glucose as carbon source and energy source in the culture medium. Results showed that the COD concentration in brewery wastewater favorable for the production of the biopolymer was 6000 mg•L-1, and an optimal culture condition of inoculum size of 5%(v/v), 28°C, initial pH 7.0 and shaking speed of 150 r•min-1, under the optimal culture conditions, the highest flocculating activity achieved for Kaolin suspension was 97.5% and 3.67 g biopolymer /L broth was obtained. The biopolymer was effective in flocculating some soluble reactive dyes in aqueous solution, reactive Light-Yellow K-4G and reactive Turquoise Blue KN-G with a decolorization efficiency of 95.8 and 96.2%, respectively，using 25 mL of the flocculant in 500 mL of 100 mg•L-1 dye solution.The decolorization efficiency was dependent on the flocculant dosage and solution pH.