The article adopted a kind of biological treatment technology of the circulating cooling water treatment. To four of the same water sample with different content of an enzyme preparation, determine water COD and ammonianitrogen through the effect of enzyme and microorganism. The results show that: The water samples have enzyme preparation played a significant effect to the degradation of COD and ammonianitrogen compared to the water sample with no enzyme preparation, and with the improvement of enzyme preparation content, the effect of the degradation of COD and ammonianitrogen reveals more and more good, and treated water is neutral. When enzyme preparation of dosing quantity for water sample of thirtytwo over one thousand, the removal rate of COD as high as 89% and ammonianitrogen as high as 95%.
Using poly(3hydroxybutyrateco3hydroxyvalerate) (PHBV) as sole carbon source, the biodegradation of the PHBV by [WTBX]Pseudomonas mendocina[WTBZ] DS04T was studied. The effect of incubation time, cultivation temperature, initial pH, shaking revolution, liquid medium volume and inoculation content on PHBV degradability were studied. According to the results of orthogonal test, the optimal conditions of enzyme production were chosen as follows: temperature 28 ℃, incubation time 32 h, initial pH 7.5, shaking revolution 150 r/min, inoculation content 1.5% , and 100 mL culture medium is load in 250 mL flask. Under the optimum conditions, the PHBVdegrading enzymatic activity reached (18.9±1.2) U/mL.
This research affords a new method to test the content of methanol in the gasoline, and a special portable instrument was developed according to this method. The disturbance caused by the existence of hydrocarbons and ethers in gasoline was excluded by extraction, and the alcohol was selective oxidized to aldehyde over catalyst A, and the presence of other alcohol can be neglected by selecting suitable color developing agent. The methanol content in 10 different kinds of gasoline samples (including samples of five Ethanol gasolines and of five unleaded gasoline) has been tested by this special instrument. According to the experimental data with GC and this method, the testing speed, selectivity and reliability of the method has been investigated, and the results shows that good reproducibility and accuracy of this method has been demonstrated as compared with those of other rapid test methods.
The contents of eleven mineral elements(Mg,Al,Ca,Mn,Fe,Cu、Zn,K,Na,Co and Pb) in twentythree green tea samples from different areas were analyzed by microwave plasma torch atomic emission spectrometry (MPTAES). Then principal component analysis (PCA) and cluster analysis (CA) were applied to differentiate the geographical origins of these tea. The result indicated that This method can discriminate the geographical origins of these tea from AnHui、ZheJiang、SiChuan and JiangXi, the classification performance was clearly, the content of the mineral elements in teas were good chemical descriptors for differentiating their geographical origins.
The catalyst stannum silicotungstat was prepared and characterized, then the esterification of nbutanol and oleic acid was studied. The effect of molar ratio of acid to alcohol, the amount of catalysts, reaction time and reaction temperature were investigated. Under the optimum conditions, the conversion ratio of oleic acid is 90.4%.
Nearinfrared (NIR) and midinfrared (MIR) spectroscopy are powerful tools for quantitative analysis of material composition due to its rapid, nonpolluting, nondestructive characteristics. The two infrared spectra show different characteristics. The advantages and shortcoming of the two spectra were analyzed and compared in the view of the mechanism, spectral analysis models and spectral instrument designs of the two spectra. This provided a good method for the selection of suitable spectroscopy. The hydrocarbon source rocks were analyzed by both midinfrared spectroscopy and nearinfrared spectroscopy. The wavelet multiscale direct orthogonal signal correction (WMDOSC) method was used to preprocess original NIR and MIR spectra. The results show that this method can significantly improve the accuracy and stability of the nearinfrared spectral analysis model, and the results of nearinfrared spectral analysis model are consistent with that of midinfrared one.
Niobium Modified SBA15 was synthesized by the wetness impregnation with niobic acid as precursor. The desulfurization of FCC gasoline was carried out with the mass fraction of 30% H2O2 as the oxidant, NbSBA15 as the catalyst, and N, Ndimethyl formamide(DMF) as the extractant. The sulfur removal rate and yield of FCC gasoline can reach 95.4% and 83.8% under the following conditions: reaction temperature: 60 ℃, reaction time: 60 min, weight ratio of catalyst/FCC gasoline: 5%, mole. ratio of oxidant/sulphur compounds 3∶1, and volume ratio of solvent (DMF) to oil was 10.
Melted oxidized paraffin wax grafted by acrylic acid was studied in this paper, it was discussed respectively about factors influencing grafted rate of melted oxidized paraffin wax, like reaction temperature, the dosage of ammonium persulphate, the dosage of acrylic acid and reaction time etc. It was ascertained that the proper conditions of orthogonal technology of melted oxidized paraffin wax grafted by acrylic acid, reaction temperature was 85 ℃, the dosage of ammonium persulphate 3.5%~4.5%, the dosage of acrylic acid 40%, reaction time 3 h.Finally, according to optimum proposal summarized by orthogonal experiment, modified oxidized paraffin wax was prepared with great characters of acid value, grafted rate, storage and centrifuge stability etc.
To study the diffusing of gas piercing leakage, finite volume method is used to establish CFD simulation model that detects different locations where gas pipes leak and four styles of diffusing, leakage of the upper, lower, windward and leeward side of the pipeline, were numerically simulated. According to the research, the leakage of lower is closer to the ground and diffuses less easily than the upper leakage, which has a 30~70 m larger dangerous area of cross range section. The leakage of windward side is similar to the leeward side, but the lengthwise section area of the former leakage is larger and more dangerous than the latter. And this simulation of leakage area provides theoretical base for safety transportation of gas and security maintenance of pipelines.
Because of Most of the oil fields have come into the high water content exploitation period, and the water injection rate increased rapidly. So to improve and meliorate the efficiency of oil field surface water injection system has become one of the important tasks in the oil field water production process. It is necessary to study the distribution rules of oil and water's movement in the oil extraction process of oil deposit. Twodimensional numerical simulation to water injection of oil extraction was maole and the regularities of distribution of water and oil was analyzed in the flat surface boundary during the process of oil extraction. This result of the study shows that at the simulation of flat surface boundary from exploitation to flow field, the distribution of the shape of water stability in the oil deposit passed through round, irregular ellipse, and topped with three oil wells like an irregular patterning. Oil distribution of the shape in the oil deposit was the range of total simulation minus water. Although stress can improve the range of oil's flushing out, the effect would be reduced by times of pressure strengthen. There is a constant cabin altitude state which is similar to a triangle and topped with three oil wells in simulation range, and this field keeps the same after the whole simulation process is stable.
Water film lubricated transport of super heavy oil is one of the energysaving technologies in the energy sector. In water film transport of super heavy oil,OFP produces a normalstress to make the water film stay steadily and no eccentrically phenomenon in the pipeline and plays a supporting role. To understand the change of the normalstress of OFP indepth in water film transport of super heavy oil, the effects of OFP to the stability of water film was analyzed through our experiments.The OFP is a viscoelastic liquid as the shear rate decreases and the solubility of OFP reduces gradually, and the normalstress difference also reduces gradually.
Based on finite volume method, a threedimensional calculation model of a wavy fin exchanger was built up for fluidflow and heattransfer study, and using CFD software, numerical simulation were carried out for fluid flow and heat transfer inside the heat exchanger of 6 different inclination angles under conditions of different air velocities. The variations of the temperature field, pressure field and velocity field in the channels were analyzed, and the variations of heat transfer, pressure drop and outlet temperature with the inlet velocity were obtained. The results show that the heat transfer, pressure drop and outlet temperature increases with the increase of the corrugation inclination; the heat transfer increases while the pressure drop and outlet temperature decreases with the rising flow velocity;obvious nonuniformity of flow and heat transfer exists between the fins,resulting in obvious heat transfer "dead zone" at the leeward side of the heat transfer tube.
The traditional baffle heat exchanger is widely used for its simple structure, safety and reliability and adaptability advantages, but the traditional baffle heat exchanger has many weaknesses:its thermal efficiency is low, shell side pressure loss is bigger and easy scaling.It is a very important engineering significance through improving the vertical baffles' structure to ameliorate the shell and tube heat exchanger's flow and heat transfer condition of shell side and reduce its energy dissipation.Baffle opening to improve the structure of a gap 0.2D height was studied by numerical simulation method. The velocity field and temperature field numerically simulated ordinary baffles heat exchanger and baffle opening heat exchanger. Under the condition of the same entering velocity of shell side, the thermal effect of baffle opening heat exchanger is better than ordinary vertical baffle plate heat exchanger.And when the entering velocity of shell side is slow, the effect is better.
The phenomenon of the oilwater two phase mixed flow is often encountered in the gathering and transportation pipeline, and the study of its pressure variation is important for the gathering pipeline design and operation. Using VOF model to simulate numerically the oilwater two phase flow in bend duct of oilfield surface gathering pipe under different moisture content of crude oil and fluid velocity. Through the analysis of the calculation results, it was known that the moisture content of two phase flow and flow velocity has great influence on the pressure drop in bend duct. With the increase of moisture content, the two phase flow pressure in bend duct increases.The elbow inner wall pressure is reduced while the speed increases, the outer wall of the pressure increases while the rate decreases. While increasing the flow rate, the high moisture content of the oilwater two phase pressure drop first decreases and then increases.
In regions of complex terrain, refined oil will inevitably pass after elevation, shutdown, such as downhill different path. The pipe inclination angle and shutdown time of downhill pipeline blending have a great influence on mixed oil characteristics. Using CFD multiphase flow model and studying three-dimensional inclined pipe, on the shutdown time, angle and sequence transportation on mixed oil characteristics were numerically simulated respectively. The results of the study show that before shutdown while the forward gasoline and backward diesel, the dip angle is bigger, the mixed oil quantity is less; the inclination angle is smaller, it is more prone to mixed oil. When the forward diesel and backward gas ,contaminated tail is longer and the inclination angle is bigger, the mixed oil quantity is bigger while the inclination angle is smaller, the mixed oil quantity is less but there is less effect on the mixed oil. The inclination angle has greater influence on the former than the latter.After shutdown, the longer the time of shutdown is, the more the mixed oil is with the equal angle. With the same time, the bigger the angle is, the greater the mixed oil. While the forward diesel and backward gasoline, with the shutdown time prolonging the mixed oil quantity is more and more uniform. When the inclination angle and the angle of pipeline is the same, shutdown time and angle has greater influence on the condition of the forward gasoline and the backward diesel.
Through 3d ANSYS software, the belt pumping unit 3d model was established, the belt pumping unit structure was analyzed. Got the support maximum stress and displacement distribution maps, got some conclusion by analyzing the results. Based on this for the pumping unit for structure optimization design, three kinds of improved models was put forward, though the three kinds of models analysis, got the three models of the displacement and stress distribution maps. The results show that even the oil pumping unit design meet the requirements, it also can proceed the further optimization, changing the stress smaller angle stress model and raking prop, strengthen the main force position, not only greatly improve the stress state, but also make the structure more reasonable, economy applicable.
Took the boom of small hydraulic excavator working device as the research object, finite element analysis model was done. Pro/E 3D software was used to build the threedimensional model of the boom of the excavator working device, then imported into ANSYS software through seamless interface software Pro/E and ANSYS software. In addition, ANSYS was used to carry out the static and modal analysis of the boom, and corresponding stress contours, displacement contours, modal frequencies and vibration modes were obtained, which offered theoretical references for the structure optimization design.
Turbine rotor fault diagnosis is the key to ensuring the safe operation of the steam turbine. Vibration signal analysis is widely used in turbine rotor fault diagnosis. The wavelet packet analysis method was adopted to extract the vibration signal eigenvalue as the input of BP neural network, the nonlinear mapping relationship between signal features and fault type and realizing the fault diagnosis with BP neural network was established. The simulation results show that this method can effectively diagnosis turbine rotor fault.
By analyzing the failure of ERPN32200 pump mechanical seal, it was found that the actual sealing effect of mechanical seals is related not only to the performance itself, but also to the precision, size, and assembly quality of the relevant parts. In the meantime, it was proposed that the corresponding measures to cope with the problems, thus prolonging the service life of mechanical seals.
The stability problem for a predatorprey system with Allee effect was studied. The existence for the positive fixed points of the system with harvesting in the predator was investigated. Then the stability for the positive fixed points of the system was analyzed by the stability condition of RouthHurvitz. Finally, numerical simulations displayed the complex dynamical behaviors.
Embedding and extracting algorithm for watermarking in the frequency domain based on the Fresnel and Fourier Hologram was proposed. The image watermarking was restored from the JPEG images with different compression ratios and the stability of watermarking image was compared between two different transformations. The result show that the image watermarking obtained by the proposed algorithm had perfect imperceptibility and stability. By comparison, however, the one based on the Fresnel Hologram had superiority in terms of stability.
With the fast development of computer network, the network management is becoming more and more complex. In order to improve the intelligence and operability of network equipment and service management, the high efficient and accurate discovery of network topology has been important process of network management. A method to conduct network topology autodiscovery in network layer and data link layer by using SNMP agreement was put forward, which enables topology discovery computation to become simpler and have high efficiency.
Let [WTHX]A[WTBX]=(aij)∈Cn×n[WTBZ], if there exists α∈(0,1) which can make |aii|≥Rαi([WTHX]A[WTBX])S1-αi([WTHX]A[WTBZ]) be right for i∈N={1,2,…,N}, then [WTHX]A[WTBZ] is called a [WTBX]α[WTBZ] chain diagonally dominant matrix. By using concepts and properties of the [WTBX]α[WTBZ] chain diagonally dominant matrices;irreducible [WTBX]α[WTBZ] chain diagonally dominant matrices and generalized strictly [WTBX]α[WTBZ] chain diagonally dominant matrices, some sufficient conditions for a matrix to be a nonsingular [WTHX]H[WTBZ]matrix were given. The results obtained improve the known corresponding results.At last a numerical example is given for illustrating advantage of result.
By using two forms of magnetic field to have an effect on negative corona discharge, the influence of magnetic field on different interelectrode area of corona discharge was studied. The research showed that the charging intensity is changed and the discharge current is increased when the magnetic field is applied to the corona zone. But the discharge current is not changed when the magnetic field is applied to the charging region. This well explained the reasons for the increase of the discharge current. Meanwhile, the research shows that the onset voltage of negative corona discharge is decreased when the magnetic field is applied. The main reason is due to that the electric field intensity of the corona region is enhanced when the magnetic field is applied.
The general principle and procedure of the data envelopment analysis (DEA) was expounded and were applied to study the practice in performance evaluation of commercial banks. An evaluation index system was established in which evaluation indicators of input and output were chose to evaluate the commercial bank's operation. And 14 listed commercial banks were selected as the research objects and operating performance was evaluated through empirical analysis.
Semiconductor IC manufacturer's channel management performance was divided into four factors: product strategy, pricing strategy, channel strategy and technical support. Research model is based on Katsikeasetal's (2004) model on supply chain performance to study the relationships between the performance factors. Questionnaires were given out to employees of 8 authorized distributors of a well known semiconductor IC manufacturer for data analysis on the research model. 190 valid samples were collected. Pilot study used 20 samples to run Cronbach's Alpha, KMO and Bartlett's tests to ensure the reliability and adequacy of the factors and measures. Five hypotheses were tested using correlation and regression analysis. Results suggest that pricing strategy is the most influential factor to manufacturer's channel management performance out of the 4 factors in this study. Suggestions on how to reform product strategy, pricing strategy, technical support and channel strategy were given to improve IC manufacturer's channel management performance.