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51.
In contrast with the big empahsis put on the process design technology, not much attention has been drawn to the technical development in the field of plant operation. Application of computers to the problem of plant operation is considered to have a great significance in establishing the man-machine system of high qualityThe roles of human operators seems to be changing along with the extent of computer application in plant operation. The importance of development of the inteligent man-machine interface with the aid of computer is stressed.One of the most crucial problems in plant operation is the system failure, where the systematic diagnositics is required. The possibility of development the computer aided diagnostic system is investigated.From recognition of the needs for avoidance of the chaos in plant operations to be created by the human factors, synthesis of operational procedures is considered to be an interesting target for process system engineering.  相似文献   
52.
Simulation of pyramid type three-roll bending process   总被引:2,自引:0,他引:2  
A simulation of the deformation of a workpiece with a U-shaped cross section in a three-roll bending process is performed. Based on the properties of the workpiece, the distribution of curvature and bending moment are calculated in accordance with the displacement and the rotation of the rolls. The relationship between the position of the rolls and the final curvature of the workpiece is obtained. An experiment is performed and the accuracy of the simulation is confirmed.  相似文献   
53.
We have discovered a novel compound, NO-1886, which possesses a powerful lipoprotein lipase (LPL) activity-increasing action. Administration of NO-1886 increased LPL activity in the postheparin plasma, adipose tissue, and myocardium of rats, and produced a reduction in plasma triglyceride levels with concomitant elevation of HDL cholesterol levels. Administration of NO-1886 increased LPL enzyme mass in postheparin plasma and mRNA activity in epididymal adipose tissue, and it was concluded that the mode of action of this compound is stimulation of tissue LPL synthesis. We also conducted long-term studies to assess the impact of increases in LPL activity and HDL levels on the development of atherosclerotic lesions in rats. Administration of NO-1886 for as long as 90 d significantly decreased the degree of atherosclerotic changes in the coronary arteries of vitamin D2-treated, cholesterol-fed rats. Statistical analysis indicated that increased concentration of HDL is the factor contributing mostly to the prevention of coronary artery sclerosis. In summary, the results of our study indicate that compound NO-1886 increases LPL activity, causing an elevation in HDL levels, and that long-term administration of NO-1886 to rats with experimental atherosclerosis provides significant protection against the development of coronary artery lesions.  相似文献   
54.
A method for cause and effect analysis of chemical processing systems has been developed on the concept of a signed directed graph. The signed directed graph, called a “model graph,” is used for representing cause and effect relationships among process variables in a system, and a “Pattern” on the graph is introduced to represent a state of the system, which is specified by “0” for normal state, “ + ” and “ ? ” for larger and smaller deviation from the normal state, respectively. For a given model graph and pattern on it, the cause of state changes and the manner of their propagation are easily found out by the present approach, which is mainly based on the depth-first search algorithm developed by Tarjan. As an illustrative example, a propane vaporizer has been taken to show the usefulness of the present approach.  相似文献   
55.
We have solved the crystal structure of the Fab fragment of NMC-4, a mouse monoclonal antibody that binds to the A1 domain of von Willebrand factor (vWF). Two Asp and three Tyr residues in the complementarity determining regions 1 and 3 of the heavy chain exhibited a spatial orientation suggestive of a dominant role in establishing contact with the antigen. A cluster of Asp and Tyr residues occurs also in a region of the platelet glycoprotein (GP) Ib alpha amino terminal domain known to be critically involved in vWF binding. Thus, the structural information obtained with NMC-4 may prove relevant to understand the stereochemical bases of the GP Ib alpha-vWF interaction essential for thrombus formation at sites of vascular lesion.  相似文献   
56.
A rare case of primary pineal melanoma is reported. The patient was a 53-year-old woman who complained of a severe headache. Computed tomography and magnetic resonance images revealed obstructive hydrocephalus caused by a mass lesion in the pineal region. A biopsy was performed through an occipital transtentorial approach. A black pigmented solitary tumor was seen without leptomeningeal dissemination. Histologic examination revealed melanoma. Chemotherapy consisting of dacarbazine, ACNU, vincristine, and interferon was used. Follow-up imaging studies showed dramatic reduction of the tumor without recurrence for 4 years. This report demonstrates that a solitary primary intracranial melanoma without leptomeningeal dissemination and with rare mitoses may yield a good result with chemotherapy.  相似文献   
57.
Plasticity theory for porous metals   总被引:6,自引:0,他引:6  
A plasticity theory for porous metals is proposed. From the stress-strain curves for sintered copper with various apparent densities, the stress-strain curves for pore-free copper is calculated by utilizing the basic equations.The equations are applied to frictionless closed-die compression and the stress in the direction of compression is evaluated in relation to the relative density and is compared with experimental results.  相似文献   
58.
Multi-elemental traces comprising particulate matter in natural water collected during summer in 1978 and 1979 from British Columbia, Canada, were analyzed by α-particle excited X-ray fluorometry. Common elements from all waters examined were Si, Cl, Ca and Fe. The similarity of their distribution in different aquatic environments was statistically analyzed. They were distributed homogeneously in the marine environment but heterogeneously in the freshwater environments. No heavy metals concerned with the environmental standards were detected for all waters examined.  相似文献   
59.
To investigate the mechanism(s) of degradation of leptin, the protein product of ob (obese) gene, we measured serum leptin levels in 70 patients with chronic renal failure (CRF). The median of serum leptin concentrations of 36 male and 34 female patients with CRF were 7.3 ng/ml ranging from 0.5 to 39.0 ng/ml and 34.9 ng/ml from 1.1 to 76.1 ng/ml, respectively, while those of 29 male and 29 female healthy subjects were 5.8 ng/ml ranging from 0.5 to 37.7 ng/ml and 12.0 ng/ml from 2.0 to 45.2 ng/ml, respectively. The difference in male and female serum leptin concentrations between CRF group and the normal counterpart was statistically significant (p<0.005 and p<0.05, respectively). However, there was no significant correlation, either between serum creatinine or BUN, and serum leptin concentrations. These findings suggest that leptin is degraded and/or filtered in renal tissue.  相似文献   
60.
The development of functional nanofiber materials with high specific surface area and porosity has been a highly interesting field of research in recent years due to its versatile properties for diverse applications. The combination of nanofibers into material clothes can open up new opportunities to improve comfort performance and thermal management properties. In this work, we demonstrated that the porous lightweight nanofibrous membrane could be coated on the fabric and laminated to improve its thermal comfort. The polyacrylonitrile was electrospun onto the surface of the polyester fabric with three different fineness and laminated with a warp knitted interlining in a controlled condition by sewing/fusing. The effect of the nanofibers diameter, sewing and fusing process on thermal insulation, air permeability, breathability, and water resistance of the obtained three‐layer samples were studied. The results showed that the presence of the nanofibers thin layer could improve the thermal comfort by controlling the studied parameters compared to the external face fabric as control. It was obtained that the fusing technique is more efficient than sewing for this purpose. The fused samples are waterproof and windproof, while instantly venting moisture and had good thermal insulation to protect the body from cold. POLYM. ENG. SCI., 59:2032–2040, 2019. © 2019 Society of Plastics Engineers  相似文献   
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