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According to the the characteristic of tower structure and manufacturing property, the tower components are divided into the purchased (CP), the cooperative (CS), the inherit (CL), the key (CK) and so on. In order to ensure the product data integrity, consistency and correctness in chemical tower, different processing rules are adopted to CP, CS, CL, CKin mapping from EBOM(Engineering BOM) to PBOM(Proeess planning BOM). Based on EBOM view in UG, the mapping function from EBOM to PBOM is established to process all BOM data. PBOM view is created accordingly, to achieve computer aided design on BOM in the data management for chemical tower.

In UG(Unigraphics) environment, computer aided design on Bill of Materials (BOM) for chemical towel is developed using the development tools of VB. By depth traverse to the assembly structure tree,part properties are extracted from the parts information library in the tower assembly. These information are saved to the BOM management library, to generate the Engineering BOM(EBOM) view. The application module is the base for the further process planning and manufacturing.

Spline finite strip method is the basic theory to analyze the cold-bending formation. Based on principle of virtual work by spline finite strip method, energy model of strip element was established. The qualitative forming factors which are difficult to quantify, and the constraint conditions to form model were given into information description. Combing with specialist experience, solving task system of multi-Agent was established. By amending the Agent of knowledge containers and social relationships, every random factor influencing on forming quality effected objectively in the multi-Agent systems based on the changing environment. Then, the formation of dynamic task is solved. This work can provide theoretical guidance for complex design of steel in roll pass.

The detail and design of numerical control system for SLS are discussed. With the help of Visuall C++ and tool kit ObjectARX in AutoCAD, the data information of the 2D contours are extracted from model in AutoCAD by data processing, and these data are transferred to laser scanning data, finally NC codes for processing are generated. A new kind of adaptive slicing algorithm that determines the slicing thickness by comprehensively considering the surface normal and the cross-sectional area, is adopted in data processing. The preheat temperature, scanning speed, laser power and thickness of spreading layer are main factors to part quality in Selective Laser Sintering(SLS). Sintering parameters are optimized by orthogonal experimental design. And a matching rule between scanning velocity and laser power is established so as to realize the laser power matching in different scanning velocities. In order to maintain and transplanted the system, the modular structure is used in the procedure of system design.

Spline finite strip is the common theoretical analysis method to sheet materials. On the mechanism of cold forming, using spline finite strip theory, characteristic line connection and characteristic finite strip are to build on the reasonableness. Ignored a number of uncertainties, avoided "massive" data, this model simplifies the boundary conditions, improving the system agility. The qualitative factors which are difficult to establish mathematical expression in forming, and the constraint conditions to form model, were tranformed into information description. Combing with specialist experience, solving task system of multi-Agent was established. Then, the dynamic task can be solved by intelligent Agent. This work can provide theoretical guidance for research to sheet materials forming.

Calculation model of the varying stress responsing to dynamic road in two degree freedoms is deduced from the moving load effecting on stress change in asphalt pavement structure. There are some constraint conditions and objective factors in varying stress response. Aiming at the impact of qualitative factors which are difficult to quantify, according to specialist experience, system of multi-Agent was established by amending the Agent of knowledge containers and social relationships. Multi-intelligence Agents had an ability of self-adjustment by accommodating itself to environment changes. Then the dynamic task can be solved by intelligent Agent. It reflects objectively the pressure state of the pavement and definitely specific cause for early danage in pavement. This work can provide theoretical guidance for further study the relations between vehicle and pavement.

Hydroxyl terminated lactic acid prepolymer was synthesized with poly ethylene glycol (PEG).The malaya acid anhydride modified PLA by fuse polymerization, and the different technological conditions (temperature, reaction time and so on) were discussed by the orthogonal design approach. The result of the orthogonal test indicated that, the product molecular weight had enhanced greatly with the Malaya acid anhydride and the PLEG mass ratio 1:15, at 130°C for 15h. The products were characterized by DSC, IR and SEM, Mechanics performance and water affinity performance of the products was determined, and the degradation behavior in vitro simulated bioenvironmental condition was studied. Mechanics performance was improved, and the good water affinity performance biodegradability was maintained.

Sintering temperature influences on sintering process essentially. Laser power and scanning speed determined sintering temperature. Preheat to powder is beneficial to improve the surface temperature uniformity. Stress concentration of part is various in different layer depth. Therefore, the influence of laser power, scanning speed, thickness of spreading layer and preheat temperature on part quality in selective laser sintering(SLS) are main factors. Based on laser energy in Gaussian distribution and mechanism of SLS, with manufactured specimen pieces by molding machine AFS-450, orthogonal experimental design and analysis of variance are adopted to post-treatment. The prototyping sintering parameters are optimized. The result and solution of the experiment are the preheat temperature of 100°C, the scanning speed of 2000 mm/s, the laser power of 24W, the thickness of single layer of 0.2mm for ABS resin. This work can provide optimized parameters in SLS for ABS resin. It will be of benefit to improve the part dimensional precision and strength.

In this paper, nano-Ti3SiC2/MoSi2 composite, whose second phase was 20-150nm, was in situ prepared by mechanical activation (MA) and SPS process with the quaternary powers of Mo, Si, Ti, and C. The results showed that: (1) matrix MoSi2 has strong repulsion to other elements, which leads to more second-phase particles inside the matrix rather than on the matrix surface; (2) matrix MoSi2 has strong restriction on the growing of the second phase, which makes the particle diameter of the second phase inside the matrix only in 200 nm around, while that over the surface reaches to 800 nm around.

To explore the effect of prophylaxis on youth's chronic mountain sickness(CMS) who moved to an altitude of above 5 000 meters by long-term oxygen therapy (LTOT).Ninety-six male youth stationed at 5 070 m, 5 200 m and 5 380 m took oxygen continuously by nasal cannula (LTOT group) every body per day. One year later, epidemiological survey were carried out according to the international CMS diagnostic criteria consist of examining right ventricle end-diastolic dimension (RVED), right ventricular anterior wall (RVAW), right ventricular outflow tract (RVOT), main pulmonary artery (MPA), left ventricular end systolic diameter (LVSD) by ultrasonic diagnostic apparatus, and blood test of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (gamma-GT), creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO), nitric-oxide synthase (NOS) blood oxygen saturation (SaQ2). Then, they were compared with 91 males in the same group stationed at the same altitude (without any interventions, control group).(1) The epidemiological survey showed that, SaO2 were increased significantly (P0.05) and the prevalence rate of CMS were decreased compared with that of control group (P0.05). (2) Echocardiography showed that SOD, NO, NOS were increased (P0.05 or 0.01) and LVSD, MPA had no significant difference compared with that of control group (P0.05). (3) Biochemical index showed that, SOD, NO, NOS were increased (P0.05 or 0.01), MDA, ALT, AST, LDH were decreased (P0.05 or 0.01) and gamma-GT, CK had no significant difference compared with that of the control group.At high altitude, LTOT can reduce lipid peroxidation, improve the important organ injuries caused by hypoxia and protect the mitochondria respiratory function and play an important role on the prevention of chronic mountain sickness.

To achieve the complex forming in open cross-section steel, this thesis established a mechanical model with spline finite strip method based on deformation characteristics of non-uniform division of spline finite strip. It determined the spline area and tie line rationally, simplifies boundary condition in designing pass structure. Aiming at the the impact of qualitative factors shaping which are difficult to quantify, according to specialist experience, theory system of Multi-Agent was established by amending the Agent of knowledge containers and social relationships. This work can provide theoretical guidance for complex design of steel in pass section.

A biamperometric method for the direct determination of pyrogallol compounds has been designed for flow-injection analysis. The method is based on the electrocatalytic oxidation of pyrogallol compounds at one pretreated platinum electrode and the reduction of platinum oxide at the other pretreated platinum electrode to form a biamperometric detection system with the applied potential difference of 10 mV. Three important compounds, pyrogallol, gallic acid and tannic acid, have been detected by the method. The linear relationships between currents and the concentrations of pyrogallol, gallic acid and tannic acid are obtained over the range 1.0x10(-6)-1.0x10(-4), 1.0x10(-6)-1.0x10(-4) and 1.0x10(-6)-2.0x10(-4) mol l(-1) with the detection limit of 6.0x10(-7), 6.0x10(-7) and 8.0x10(-7) mol l(-1) (S/N=2), respectively. The R.S.D. observed for 30 successive determinations of 5.0x10(-5) mol l(-1) pyrogallol, gallic acid and tannic acid are 1.9, 2.5 and 2.0%, respectively. Most ions and organic compounds tested are found not to cause significant interference in the determinations. The method is simple, selective and efficient (180 h(-1)), performing well as a routine assay, and has been validated by the determination of pyrogallol compounds in tea and Chinese gall.

In the title complex, [Zn(C6H5N2O2)2(H2O)2], the Zn2+ cation lies on an inversion centre and the coordination geometry is distorted octahedral, with two N atoms and two O atoms from the 5-methylpyrazine-2-carboxylate ligand in the equatorial plane. The two remaining coordination sites are occupied by two water molecules. The crystal structure is stabilized by a network of O—H...O hydrogen-bonding interactions, forming a two-dimensional supramolecular structure.

In the neutral title complex, [Fe(C(6)H(5)N(2)O(2))(2)(H(2)O)(2)], the coordination geometry aound the Fe(II) atom, which lies on an inversion centre, is distorted octa-hedral comprising two N atoms and two O atoms from two 5-methyl-pyrazine-2-carboxyl-ate ligands, and two water mol-ecules. The crystal structure is stabilized by a network of O-H⋯O hydrogen bonds, resulting in a two-dimensional supra-molecular structure.