石河子大学：《工程力学》课程教学资源（大纲讲义）材料力学考试大纲（农业水利工程）

石河子大学：《工程力学》课程教学资源（大纲讲义）材料力学考试大纲（土木工程专业）

为了克服猪脱细胞真皮基质作为组织工程支架材料渗透性差、降解速度过慢、免疫原性较强等缺点,采用多种化学、生物与物理综合方法处理猪皮制备了一种新型天然胶原支架材料,通过光学显微镜、扫描电镜观察以及体外降解时间、透水汽性、拉伸强度、孔隙率、收缩温度等的测定,对其性能进行了研究.实验结果显示:支架中的成纤维细胞、脂肪细胞及组织纤维间质完全去除,胶原纤维得到了松散,并维持其原有的天然三维网络多孔结构;该材料透水汽性处于3000g·m-2·d-1左右,适合创面恢复;体外降解时间处于25~50h之间,并可根据需要调整工艺条件控制降解时间;拉伸强度介于10.20~11.50MPa之间,具有良好的拉伸强度;收缩温度介于70~85℃之间.上述结果表明该材料已解决了猪脱细胞真皮基质渗透性差、降解速度过慢的缺点,并且其透气性和拉伸强度高、降解性优良且可控,符合组织工程支架材料的要求

transmission or many years a hydraulic system was plumbing considered the result of plumbing together number of components. Also, a hydraulic component system has been considered merely the of power for control servos. Each of these servo 1aB concepts can lead to basic errors

The Lathe And Its Construction A lathe is a machine tool used primarily for producing surfaces of revolution and flat edges. Based on their purpose, construction, number of tools that can simultaneously be mounted and degree of automation, lathes-or, more accurately, lathe-type machine tools-can be classified as follows:

conical roller Bearings With rolling Contact In bearings with rolling contact, the shaft is needle idirectly or indirectly supported by rolling elements, cylindrical such as balls, cylindrical or conical rollers, orroller needles (i.e, ylindrical rollers with a high

There are two basic methods of generating process manufacturing gear teeth,the generating process and the forming forming process process. When a gear tooth is generated, the workpiece and the grinding cutting or grinding tool are in continuous mesh and the tooth form is mesh

Product quality is al ways a matter of prime importance in manufacturing. It should be given parameter the highest priority in process planning. The quality of a machined part can be expressed in coordination geometrical parameters( dimension

3.3.1铸钢 3.3.2铸铁

3.4有色金属及其合金 3.4.1铝及铝合金 3.4.2铜及铜合金 3.4.3钛及钛合金 3.4.4轴承合金