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排序方式: 共有1816条查询结果,搜索用时 93 毫秒
41.
介绍了中温固体氧化物燃料电池(IT-SOFC)阳极材料体系及工作过程,为进一步研究新型的阳极材料奠定了基础. 相似文献
42.
人眼3D肌肉控制模型 总被引:3,自引:0,他引:3
根据解剖学原理及人眼运动特征,提出了一种人眼3D肌肉控制模型.该模型由内部模型和外部模型组成,其3D运动由3类共8条肌肉控制.模型建模及驱动比较方便,并已在PC机上进行了模拟.模拟结果表明,人眼模型逼真,可较好地模拟人眼运动及表情. 相似文献
43.
介电弹性体致动器及其应变响应研究 总被引:2,自引:0,他引:2
用介电弹性体制作的致动器,具有变形量大、能驱动较大的负载、可塑性很好的特点.给出了一种使用介电弹性体制作基本致动器的方法,对电极、预应变等对该方法制作的致动器的影响进行了实验研究.结果表明,电极的柔软度必须与材料的性质匹配.太硬的电极会使应变变小,而太柔的电极会使薄膜易于击穿.预应变虽减弱了单位电压下的变形量,但却能提高致动器的最大应变量. 相似文献
44.
论文将计算机技术应用到运动生物力学的研究中,提出并实现了针对人体肌肉力量中握力、背力的实时数据采集与分析系统。系统采用运动生物力学测量装置精确采集肌肉力量的数据,利用数据库技术存储和处理测量的数据,图形化显示肌肉力量的变化曲线,计算人体肌肉力量的多种参数,对肌肉力量进行综合分析比较。文中着重介绍了系统结构、功能及软件实现。 相似文献
45.
张元莹 《陕西科技大学学报》1997,(2)
本文提出了把在骑行过程中的脚踏力分解为直接由纯关节力矩而产生的肌肉分量和由重量与惯性力的作用产生的非肌肉分量的分析方法.在平面关节运动和关节力矩给定条件下,利用Newton-Euler系统中的动力学方程求解两个分量.通过在3个不同转速下承受普通载荷的自行车脚踏力的分析为例来说明脚踏力的分解方法.主要的结果是:非肌肉力分量的大小随转速增加而增加,肌肉力分量的大小基本保持相对恒定. 相似文献
46.
Helmut Haselmann 《Journal of microscopy》1983,129(1):1-2
Melamine-formaldehyde, a universally used technical aminoplast, can be modified into a water-compatible electron microscopic embedding medium. The complete processing of tissues—from fixation to sectioning—is described in this paper. It produces stable sections showing remarkable ultrastructural detail. 相似文献
47.
Sandeep Peddi Rapur Ram Varalakshmi Devi Boreddy Sridhar Avssn Krishna Kishore Chennu Siva Kumar Vishnubotla 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):192-194
We present an end‐stage renal disease patient on dialysis with fever. The primary source was right internal jugular vein catheter which had metastatic infections in the body probably via an arteriovenous communication in a cavity in left lung. Patient had right psoas muscle abscess and a left kidney abscess. An 18F‐fluorodeoxyglucose‐positron emission spectroscopy scan was done to find out left kidney abscess. A search of literature did not reveal many patients of psoas abscess secondary to infection of hemodialysis access. 相似文献
48.
Comparative studies of quality changes in white and dark muscles from common carp (Cyprinus carpio) during refrigerated (4 °C) storage 下载免费PDF全文
Qian Li Dongping Li Na Qin Hui Hong Yongkang Luo 《International Journal of Food Science & Technology》2016,51(5):1130-1139
Differences between white and dark muscles from common carp (Cyprinus carpio) in sensory assessment, total viable counts (TVC), total volatile basic nitrogen (TVB‐N), pH, electrical conductivity (EC), biogenic amines (BAs), nucleotide degradation products and colours were investigated under air and vacuum conditions during refrigerated (4 °C) storage. Compared with white muscle, dark muscle had a higher lipid content, but lower crude protein and moisture content. TVC, TVB‐N, pH, and L* value were higher in white muscle, while K value and a* value were higher in dark muscle. Under both conditions, white and dark muscles had significant (P < 0.05) differences in tyramine and cadaverine content. Although dark muscle was significantly (P < 0.05) lower in ATP content, it had higher rate of IMP degradation and K value increase. Taking sensory and microbial indexes into consideration, dark muscle appeared to have a longer shelf life than white muscle under both conditions. 相似文献
49.
Wan-Jing Chen I-Hsuan Lin Chien-Wei Lee Yi-Fan Chen 《International journal of molecular sciences》2021,22(4)
Aging causes a decline in skeletal muscle function, resulting in a progressive loss of muscle mass, quality, and strength. A weak regenerative capacity is one of the critical causes of dysfunctional skeletal muscle in elderly individuals. The extracellular matrix (ECM) maintains the tissue framework structure in skeletal muscle. As shown by previous reports and our data, the gene expression of ECM components decreases with age, but the accumulation of collagen substantially increases in skeletal muscle. We examined the structural changes in ECM in aged skeletal muscle and found restricted ECM degradation. In aged skeletal muscles, several genes that maintain ECM structure, such as transforming growth factor β (TGF-β), tissue inhibitors of metalloproteinases (TIMPs), matrix metalloproteinases (MMPs), and cathepsins, were downregulated. Muscle injury can induce muscle repair and regeneration in young and adult skeletal muscles. Surprisingly, muscle injury could not only efficiently induce regeneration in aged skeletal muscle, but it could also activate ECM remodeling and the clearance of ECM deposition. These results will help elucidate the mechanisms of muscle fibrosis with age and develop innovative antifibrotic therapies to decrease excessive collagen deposition in aged muscle. 相似文献
50.
Robot assisted gait training may help in producing rapid improvements in functional gait parameters. This paper presents new experimental results with an intrinsically compliant robotic gait training orthosis. The newly developed robotic orthosis has 6 degrees of freedom (DOFs). A trajectory tracking controller based on the boundary layer augmented sliding control (BASMC) law was implemented to guide the subject’s limbs on physiological gait trajectories. The compliance of the robotic orthosis sagittal plane hip and knee joints was also controlled, independently of the trajectory tracking control. The robotic orthosis and the control scheme were evaluated on three neurologically intact subjects walking on a treadmill. A maximum trajectory tracking error of 10° was recorded at the hip and knee sagittal plane joints. The results showed that subjects can walk in the robotic orthosis with comfort and the BASMC law was able to guide the subject’s limbs on reference physiological trajectories. 相似文献