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81.
复合超细丙纶及应用   总被引:2,自引:0,他引:2  
对国内外细旦丙纶的开发和发展进行了介绍,阐述了单丝纤度为0.1~0.5dtex的复合超细丙纶的制造方法、原材料规格、复合剥离技术以及产品质量。重点讨论了复合超细丙纶及织物的舒适性、染色性和卫生性,应用于织造、服装领域。  相似文献   
82.
利用平板型热管纺丝装置对普通高速纺丝机进行技术改造,并一步法生产出充分结晶的PET纤维(FCY)。该纤维可直接用于织造,调节热管温度、热管安装位置可获得满足后道工序不同需要的FCY。  相似文献   
83.
��Consulting the relevant documents at home and abroad,the author finisheid the derivation of quations about critical flow quantity,critical flow rate,contrast flow quantity,contrast flow rate which are necessary to the continuous water withdrawal through the flow string with different diameters and the rational flow string formula that should be selected when the contrust parameter1.The author also works out the solving programme for TI-59 computer and designs and draws up the nomograrn of mathematical mode.The evident economical results have been obtained from practice of optimizing the flow string for water withdrawal in gas production in Southern Sichuan and from studying the gas-water two-phase flow characteristics through vertical pipe.  相似文献   
84.
本文介绍北京核电站模拟器硬件构成并分析其功能和特点。  相似文献   
85.
Application of the Taguchi method to the optimization of the submerged arc welding process is reported. The Taguchi method is used to formulate the experimental layout, to analyze the effect of each welding parameter on welding performance, and to predict the optimal setting for each welding parameter. Experimental results are provided to confirm the effectiveness of this approach.  相似文献   
86.
Abstract—The plane-strain initiation and growth fracture toughnesses of powder-metallurgy-processed, SiC particulate-reinforced 2009 plate were measured at temperatures from 25°C to 316°C. Initiation toughness from electrical potential monitoring ( K JICi) is 18 MPa°m at 25°C, and is nearly constant to 220°C before decreasing sharply to 6 MPa°m at 316°C. Growth toughness, given by the tearing modulus ( T R), is less than 3 from 25°C to 125°C, and increases dramatically above 200°C. The magnitude and temperature dependence of initiation toughness depend on detection of the critical fracture event. Standard measures of toughness K IC and K JIC exceed K JICi and increase to a plateau with increasing temperature. The fracture mode for the composite is microvoid nucleation, growth and coalescence at all temperatures. Void nucleation is associated with SiC; such particles both crack and create stress and plastic strain concentrations that rupture the interface or adjacent matrix, particularly at corners. Matrix plasticity and cavitation increase with increasing temperature. Void growth is regular at all temperatures, but limited by adjacent SiC particles. Both K JICi and T R are governed by the temperature-dependent crack-tip plastic stress and strain fields, and the intrinsic damage resistance of the composite microstructure.  相似文献   
87.
杨文光 《辐射防护》1995,15(1):59-63,41
本文介绍一种新型高压直流电源,它的输出高压的提升、下降均自动、无级、缓慢地变化,无突变现象,尤其在电网供电突然中断时,也能使用高压自动、缓慢地下降到0。它用于半导体放射性射线探测器,可以避免由于操作的粗心或电网供电突然中继引起高压快速变化或而产生的对该类昂贵探测器及其附件的损害,使探测器的优良性能得以保持。  相似文献   
88.
PC/ABS合金的研制及其在汽车上的应用   总被引:6,自引:0,他引:6  
对PC/ABS合金开发和研制及其在汽车上的应用作了评述。介绍了上海杰事公司在该领域的进展。  相似文献   
89.
Stiffness of subchondral proximal tibial trabecular bone is a factor in the stability of prostheses implanted into that bone. The stiffness of trabecular bone in osteoarthritis (OA) has been documented. Trabecular bone in rheumatoid arthritis (RA) is osteopenic in numerous sites and morphologically abnormal in the proximal tibia. Reliable data on proximal tibial bone in RA are lacking, although 1 study failed to identify abnormalities. The purposes of this study were (1) to document the stiffness of the proximal tibial cancellous bone in patients with RA, (2) to determine the effect of angular deformity on bone stiffness in rheumatoid patients, and (3) to compare RA stiffness values with those in published reports for OA. Fifteen tibial plateau were obtained from patients with RA during surgery. Each plateau was horizontally seated in a mold and covered with cement. The plateau was divided into 6 regions, which were used to facilitate comparison between specimens and the existing literature. Indentation tests were conducted with a 4-mm-diameter cylindrical indentor controlled by an MTS machine. The indentor descended at a rate of 2 mm/min to a maximum depth of 1.0 mm; load and displacement data were digitally recorded. Stiffness was calculated from the slope of the linear region of the curve using best-fit linear regression. Where varus deformity was present, stiffness in the medial plateau was higher overall than for the other compartment; whereas in the case of valgus deformity, stiffness of the lateral side was significantly higher (P < .05 for each observation). In comparison to older normal specimens, both the medial compartment of the varus RA specimens (P < .01) and the posterolateral compartment of the valgus RA specimens (P < .01) had significantly lower stiffness. Comparison with OA specimens showed that in varus RA, the posteromedial region had significantly lower stiffness than in varus OA at the same site (P < .01). In valgus RA, the lateral region had significantly lower stiffness than in valgus OA at the same site (P < .01). The mean stiffness ratio of the valgus RA was significantly (P < .01) altered from normal, and for the varus RA, it was significantly (P < .01) different from normal posteriorly. The stiffness ratios for the varus RA were significantly (P < .01) different from those for varus OA; there was no difference between valgus RA and valgus OA. It is concluded that RA affected bone has significantly lower stiffness than normal and osteoarthritic bone. The loaded plateau is stiffer than the unloaded plateau in angular deformity, but is still less stiff than normal bone and osteoarthritic plateaus with corresponding deformities.  相似文献   
90.
刘军  石定河 《红外技术》1996,18(4):29-32
详细介绍了在改进红外焊缝检测仪的过程中实时信号的一种抗干扰方法--自相关方法。重点离自相关方法的数学模型,软件框图及设计思想,并给出了实验结果。  相似文献   
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