2002 volumne 23 Issue 03
LIU Jindun; High Love Ring; Wan Yazhen; etc

Abstract:
The preparation and performance characterization of polymer ultrafiltration membranes were studied in detail by polysulfone material and phase conversion method. In order to control its microporous structure, the membrane production conditions were systematically studied, including the selection of polymers, solvents and additives. The film-forming process conditions were optimized by orthogonal experiments. The results showed that the concentration of polysulfone in the casting solution had the most significant effect on the water flux of ultrafiltration membrane, followed by acetone content, solvent evaporation time, and polyvinylpyrrolidone content. On this basis, the preparation conditions of polysulfone base membrane were optimized: the mass fraction of polysulfone was 14%, the solvent evaporation time was 10 s, the mass fraction of acetone was 0.3%, and the mass fraction of polyvinylpyrrolidone was 0.25%.

Ren Baozeng; Li Weiran; LI Chen; etc

Abstract:
According to the solid-liquid phase equilibrium theory, combined with the characteristics of reversed-phase liquid chromatography process, a model for the determination of infinite dilution activity coefficient in water by liquid chromatography direct method was established. According to this model, the activity coefficient of unlimited dilution of four quinolones such as ofloxacin in water at different temperatures was measured by ion suppression chromatography, which not only provided key basic data for the evaluation of the environmental behavior of quinolones, but also provided a basis for exploring the biological activity mechanism and predicted efficacy of quinolones.

LI Wen; LIU Hongmin; Xiao Zhiang

Abstract:
Telomerase is considered to be a new rake for the diagnosis and treatment of malignant tumors, and the synthesis of parahydroxybenzoic acid-4-β-D-2’,3’,4’,6’-tetraacetylglucoside-1-D-2’,3’,4’,6’-tetraacetylglucosate with strong inhibitory activity on telomerase has been studied. By comparing acetone method and phase transfer catalysis, it can be seen that the yield of phase transfer catalysis is higher, and the total yield of glucose can reach 21%.

Wang Dingping; Hu Xiangbao; Guo Chaxiu; etc

Abstract:
Aiming at the current method of calculating shell-level fluid flow in bow-shaped baffle plate shell-and-tube heat exchanger using the concepts of distribution resistance and volumetric porosity, according to the structural characteristics and flow characteristics of longitudinal shell-range heat exchanger, the simplified calculation problem of numerical simulation of large-scale longitudinal shell-length heat exchanger was discussed, and the simplified calculation method of geometric prototype periodic segment model and four-tube model were proposed to solve the numerical simulation problem of large-scale longitudinal shell-range heat exchanger. Applying the simplified calculation method proposed in this paper, the general CFD software F LUENT is used to numerically simulate the flow and heat transfer of different structural parameters of the longitudinal shell heat exchanger, and the mesoscopic information of the flow field and temperature field of the heat exchanger is obtained, which provides a basis for the structural optimization design and development of novel heat exchangers for the longitudinal flow shell heat exchanger.

LIU Liping; Ma Xiaojian

Abstract:
In order to explore the possibility of further reducing energy consumption in the ammonia conversion section, on the basis of the total low-change process of a plant with an annual output of 8,<> tons of synthetic ammonia, according to the process technology and design manual of the small ammonia plant, the hot and cold logistics of the conversion section were recalculated, and the combination curve of hot and cold logistics was made from the calculation results, and the heat exchange network was optimized and synthesized by using pinch technology, and a new all-low conversion heat network was designed by changing the flow and flow route of logistics matching. Under the premise of meeting the requirements of the full low-change process, the network can make full use of the heat of the system itself, and does not need external steam supply; Compared with the second heat exchange network, the number of equipment and investment are reduced; Compared with the existing process, there is little change and has the prospect of energy-saving applications.

Buy Wen Ning; ZHOU Rongmin; Wang Zhen

Abstract:
The productive application of two-phase anaerobic system in the treatment of antibiotic wastewater showed that when the influent pH, VFA, COD and BOD5 of the two-phase anaerobic system were 5.46, 1376 mg/L, 8597 mg/L, 4126 mg/L, respectively, and the residence time of the acid generator (anaerobic baffle reactor) was 12 h, the pH increased from 5.46 to 6.18, the VFA increased from 1376 mg/L to 3281 mg/L, and the BOD5/COD increased from 0 .48 to 0. 52; When the residence time of the methanogenerator (anaerobic composite bed reactor) was 39 h, the removal rates of COD and BOD5 were 90, respectively. 4% and 94.5%.

LI Yuqing; GAO Jianlei; Cao Jun

Abstract:
Taking the industrial device of using two-phase anaerobic-aerobic SBR-flocculation precipitation combination process to treat cotton pulp wastewater as the object, the biochemical kinetic parameters of aerobic SBR unit were determined under the condition of natural change of water temperature, and the results were: V max=0.70~0.91 mgBOD5/mgVSSd, Ks=15.5~20.4 mgBOD5/L, Y=0.66~0.69 mgVSS/mgBOD5, Kd=0.03 1~0.041 d-1 ,Vmax′=0.52~0.74 mgCODcr/mgVSS*d,K s′=9.3~14.2 mgCODcr/L ,Y′=0.38~0. 45 mgVSS/mgCO

He Zhengguang; Buy Wen Ning; LIU Yin; etc

Abstract:
The necessity and feasibility of using ecological technology to control the pollution of the Shuanghu River were studied, and an ecological treatment project suitable for use in economically underdeveloped areas in China was designed. Experiments show that the removal rate of CODcr can reach 24 when staying for 58 h. 8%, more than 24 h, the increase is not obvious; The removal rate of SS reached 24.50% when staying for 7 h, but the increase was not obvious after 36 h. The design technology of water conservancy engineering and sewage treatment plant is applied to the design of stable pond, so that the water flow in the pond is effectively improved and the purification efficiency is significantly improved. Actual monitoring shows that ecological treatment works do not affect groundwater. Compared with the original proposed sewage treatment plant plan, the project not only meets the current COD reduction target, but also has a small investment and a short construction period.

Zuo Qiting; ZHANG Haohua; Ou Junli

Abstract:
Guided by the theory of sustainable development and combined with the actual needs of water conservancy planning, the basic concepts and planning ideas of water conservancy planning under the principles of sustainable development goals were discussed. A set of quantitative research methods based on the development of comprehensive index measurement DD was proposed. A new technical route for water conservancy planning under new ideas was proposed, and it was successfully applied in the Bosten Lake basin of Xinjiang.

WANG Xia; Wang Shubin

Abstract:
The truncation auxiliary function method for finding the accurate solution of nonlinear partial differential equations is briefly introduced, which is concise and effective. Using the truncation auxiliary function method, with the help of the computer algebra system Mathematica, a new nonlinear dispersion-dissipation equation for describing the evolution of ionic weak nonlinear ion acoustic waves composed of cold ions and hot electrons is obtained, and new soliton solutions, periodic solutions and several sets of steady-state solutions are obtained. These solutions contain arbitrary constants, and when any constant takes a specific value, the computer algebra system Mathematica gives a graph of the partial solution.

Han Jie; Shi Laide

Abstract:
The idea of full-spectrum analysis technology is introduced, the theoretical relationship between full-spectrum analysis technology and rotating machinery rotation signal is studied, and the theoretical calculation formula and concise numerical algorithm based on composite signal are derived from full-spectrum analysis, and applied to the actual fault diagnosis system. The research and application show that the full-spectrum analysis, as an analysis method for the comprehensive processing of rotor vortex signals, can clearly deal with the relationship between rotor trajectory and positive and negative precession, and the rotation intensity of the rotor can be identified after simple conversion, indicating that full-spectrum analysis is a very practical analytical tool for fault diagnosis of rotating machinery.

Hua Shaojie; Xu Sha; Xia Boqian; etc

Abstract:
In view of the defects in the dynamic and static pressure spindle system of 3MK133 channel grinder, the shallow groove of the throttle is easy to block and inconvenient to disassemble and clean, and the end-mounted flow restrictor is proposed to replace the original built-in shallow groove restrictor, change the gap throttle to capillary throttling, and adjust the taper, oil return path, sealing device and sealing method of the tapered bearing in the spindle system accordingly. The finite element calculation and analysis show that the improved bearing has the typical characteristics of pressure distribution of dynamic and static pressure bearings, which effectively improves the bearing capacity, reduces the friction power consumption, has a good throttling effect, and maintains the various excellent properties of the original spindle system.

Yang Jincai; Wang Dong

Abstract:
Starting from the definition of Hamming’s closeness, it is analyzed that when there are many fault mode features, the part reflecting the difference in the proximity calculation formula is greatly attenuated, resulting in a decrease in the difference and a decrease in resolution. Furthermore, a new proximity calculation method is proposed and proved, which improves the attenuation of the difference part by properly determining the calculation parameters, effectively improves the resolution in engineering use, and verifies with specific examples.

ZHANG Yongyu; Cen Shaoqi; Yang Jinfeng

Abstract:
When the deep and shallow gap throttling floating ring dynamic and static thrust bearings are running at high speed, the influence of the inertial force of the fluid increases, which eventually leads to the flow state changing from laminar flow to turbulent flow. Using the general empirical method considering the fluid turbulence effect, the corresponding turbulence Reynolds equation is established by adding turbulence factor to the left term of the equation on the basis of obtaining the unsteady Reynolds equation for radial thrust floating ring dynamic static thrust bearings that are included in the migration inertia term. The finite element method is used to obtain the pressure field distribution of the bearing inner and outer membranes, and the results show that the pressure field distribution under turbulent flow state changes significantly compared with the pressure field of laminar flow under the same working conditions, so that the performance parameters of the bearing also change accordingly.

Ma Shenggang; Zheng Yanping; Zou Du; etc

Abstract:
In simulating the new type of hydraulically controlled inertial vibration system, a new method of "segmented modeling and serial simulation" is proposed in view of the problems that are difficult to establish mathematical models and difficult to debug simulation programs, and the models of hydraulic control systems and mechanical vibration systems are established respectively, and the complex systems are divided into simple subsystems, so that the system simulation program has strong versatility and flexibility. Experiments show that the simulation model established by the above method is reasonable and can be used as the basis for system analysis.

Lu Xiaoyong; Berger Hou; Jiang Wenbing; etc

Abstract:
By analyzing the helical bevel gear CNC machining machine tool mechanism, a five-axis CNC machining machine tool model is established, and according to the tool position file (tool center coordinates and tool axis vector) generated by pre-processing, the helical bevel gear post-processing formula is derived by using the post-processing principle of ordinary CNC machine tools, and the machine angle distribution and the position of the tool core in the machine tool coordinate system are obtained, thus providing a method for the generation of CNC code from tool trajectory.

HUANG Rengui; Zheng Yanping; SUN Yan; etc

Abstract:
In the process of machining, the plane vibration-elliptical motion between the tool and the workpiece is discussed, which can be decomposed into any two harmonic vibrations in the perpendicular direction of each other, and the phase difference between these two harmonic vibrations is derived as the diagnostic parameters of mode coupling cutting flutter. At the same time, taking turning and boring as examples, the machining curve equation when mode shape coupled flutter occurs in the machining process system is established, and the influence of flutter on the geometry of machining surface is analyzed.

KEWEN WANG; JIANG Junfeng; LIU Xianlin; etc

Abstract:
According to the specific characteristics of the 10 kV distribution line of the power system, the sensitivity analysis technique is used to calculate the reactive power compensation. From the perspective of practical application, the composition of optimization problems, the calculation of power loss and voltage distribution, and the treatment of load shape coefficient are described. The calculation and application of sensitivity coefficient and the determination of the final scheme of reactive power compensation are introduced in detail. Based on the calculation of dozens of actual 10 kV lines, it is explained, analyzed and discussed. The sensitivity of the reactive power injection of the node is estimated and ranked by using the economic objective function, and then the accurate trial calculation is only for a limited number of schemes. The positioning of the capacitor in the 10 kV distribution line and the determination of the optimal compensation amount are completed on the basis of considering the actual capacity and group of the capacitor.

Yang Liyu; WANG Jinfeng; Chen Genyong

Abstract:
Aiming at the disadvantage of slow speed in solving distribution network optimization problems by traditional methods, a Tab u search algorithm with fast search capability is introduced. In order to make the planning results more intuitive, the Geographic Informa tion System (GIS) platform was introduced. The optimization model considers the time value of line investment, aims at minimizing the annual cost considering investment and loss costs, takes the line transmission capacity and radiation of the distribution network as the constraints, takes the spanning tree of the alternative network as the initial solution, and uses the Tabu search algorithm to optimize it. The example results show that the proposed method has certain feasibility and effectiveness.

LI Jianping.

Abstract:
Based on the system analysis of network-based remote monitoring, configuration king software characteristics and the working process of air compressor, a low-cost solution for remote monitoring of air compressor using industrial control machine combined with Ethernet network technology is proposed. Introduction in the industrial environment, using industrial configuration software - Configuration King software, using Ethernet network based PC data acquisition method and parameter method to realize the fault diagnosis of air compressor, a remote online real-time monitoring system based on Ethernet network air compressor station is designed, remote automatic monitoring and fault diagnosis of the operating status and operation process of the air compressor through Ethernet, realizing the integration of unattended, remote monitoring and management control.

FENG Jingfeng.

Abstract:
It introduces that the switch billing system realizes a variety of charging through the payment platform system, including real-time collection, pre-deposit collection, collection and payment, and hair-trigger. Real-time collection is immediately collected from the bank when the user incurs a certain fee, pre-deposit collection is the collection of pre-deposit when the user enters the network, the pre-deposit is the user goes to the bank to pay, the bank collects cash, and the touch is that the user deposits the expenses he generates from the personal account to the enterprise account through the voice prompt of the enterprise’s customer service system.

Ren Chenxing; SUN Yufeng; Tang Yali; etc

Abstract:
The nucleation dynamics and microstructure of Al-(1~5)Cr (mass fraction) fast-setting alloy were calculated and studied by continuous cooling, and the relationship between the nucleation gestation period and the cooling rate under different components and different cooling rates was obtained, and the phase selection law in the solidification process was obtained, that is, the preferential precipitation of a certain phase was caused by its nucleation kinetic conditions being more advantageous than other phases. Specific to Al-Cr alloys, with the increase of solute content, the critical cold rate required to inhibit the first nucleation of intermetallic phase increases, that is, the tissue of completely supersaturated single-phase α-Al can only be formed in a large cold rate or a very thin band, and the calculation results are in good agreement with experimental detection.

Bai Xiaoli; Wang Yaming; LI Qian; etc

Abstract:
Some crystallization properties of PET, PET/clay nanocomposites and tackified PET/clay nanocomposites were tested by differential scanning calorimetry, and the cold crystallization peak, subcooling degree and crystallization temperature range were compared respectively, and the results showed that the cold crystallization starting temperature of PE T/clay nanocomposites was lower than that of PET. PET, PET/CLAY NANOCOMPOSITES, TACKIFIED PET/CLAY NANOCOMPOSITES UNDER THE SAME CONDITIONS OF SUBCOOLING TM-T′M SIZE ORDER IS PET/CLAY NANOCOMPOSITES<TACKIFIED PET/CLAY NANOCOMPOSITES TACKIFIED PET/CLAY NANOCOMPOSITES > PET. This indicates the dispersion of the clay nanosheet layer in PET

LI Jian; LI Qingfu; Li Bing

Abstract:
According to the settlement detected in the long-term operation of a immersed tunnel, the mechanism of settlement problems that have been neglected by engineers and technicians is analyzed. It is pointed out that the siltation of river channels, reciprocating loads and overloads of tidal tides can cause settlement of immersed tunnels, and the settlement control measures of regular dredging, pipe bottom grouting and pile foundation reinforcement and the calculation method of the reinforced pipe body are proposed. For an actual project, the bearing capacity of the foundation in the reinforcement calculation was analyzed, and the pile foundation reinforcement scheme was proposed, and the internal force and reinforcement of the pipe body itself were analyzed through the structural calculation of the reinforced pipe body.

Yang Jianshui; Han Juhong; Wang Xiaomin

Abstract:
The secondary stress test of 13 four-sided simple support superimposed rectangular plates under concentrated load was carried out, and the force performance of the four sides was systematically analyzed, and the isoshear stress line model of the superimposed surface was proposed. The test results show that the bearing capacity of the laminated plate is not lower than that of the whole cast plate with the same conditions. The concrete strength of the two stages of concrete in the laminated plate is lower and has control over the bearing capacity of punching and cutting. It is suggested that the composite surface of the laminate plate can adopt a natural rough surface, and in the shear design of the laminate, in addition to meeting the calculation of the bearing capacity of the punching cut, the shear stress on the superimposed surface should also be verified according to the given shear stress formula.

HU Liangming; Li Zongkun; Zhou Hongjun

Abstract:
Aiming at the cumbersome problem of calculating the interface cracks of the heteroelastic mold by the finite element method, the variation law of stress intensity factors of the interface cracks in the heel area of gravity dams under the action of earthquakes was discussed by the special solution boundary element method, and it was concluded that the stress intensity factors KI., KII., and K0 decreased with the increase of the elastic-mold ratio and increased with the increase of fracture length, and the ground water pressure had a greater influence on the cracks of gravity dams. The example shows that the special solution boundary element method is an effective method for calculating the dynamic fracture of heterogeneous fractures.

Yu Danjiang; Chen Huai

Abstract:
Curvature mode is the sensitive labeling quantity of structural damage recognition, using numerical simulation method, the curvature mode is used for bridge damage recognition, before the introduction of noise in the displacement mode, the curvature mode detection method can accurately determine the location of the damage, at this time, the detection results have high accuracy and precision, can detect the damage in the structure. After the noise is introduced, when the displacement mode noise is less than 1%, the influence of noise is not obvious, and the damage position can still be detected, but when the displacement mode noise is greater than 1%, the damage position cannot be detected.

LIU Zhonghua; Li Tian

Abstract:
The numerical method is used to discuss the calculation of stable limit load in the plane of wedge column, and the method of mixed iteration is adopted in the iteration condition to avoid the problem of iterative non-convergence in the calculation of cross-section M-P-Φ relation. The elastoplastic condition is applied to the calculation of the load-deflection relationship of the component, which optimizes the calculation process and shortens the calculation time. The change law of ultimate load with wedge rate and bending moment ratio at the end of the column was analyzed by using the program. The conclusions obtained can be used for the reference of designers.

Yang Yongzhan; Square wave; Ren Rizhong; etc

Abstract:
The damage diagnosis and analysis of building structures is the basis for structural performance evaluation. The static detection method is used to analyze the damage diagnosis problem of beam components. According to the change of the equivalent flexural stiffness of the beam section, the mechanical model of the beam is established, and the damage diagnosis and analysis method of beam members is established based on the deflection change of the beam under concentrated load, and based on the principle of system identification. Through example calculation, it shows that the proposed method has good convergence and stability.

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