side dump truck

This shows the grinding jet used for slit is based on the theory of trihedral adherent wall jet.

研究了油田油井中磨料射流割缝的机理,阐明了磨料射流割缝时流体在缝隙中流动的状态,讨论了水力喷砂割缝时射流流动情况,认为在套管中对套管割缝时系自由淹没射流,说明了油井中磨料射流割缝是三面附壁复合射流的原理,解释了不同材料在高压水射流作用下的破坏形式和为什么淹没磨料射流在压力很低的情况下仍然能够将靶距为1000mm以外的5mm钢板击穿。

00DS) were evaluated preoperatively for the presence of vitreoretinal changes using Goldman three-mirror contact lens before LASIK.

目的:了解LASIK术前高度近视眼散瞳三面镜眼底检查的结果及类型。

Methods A research method was used to compare the results of the Optos-Panoramic200 scanning laser ophthalmoscope exam of LASIK patients with the results of the Goldman three-mirror contact lens examination for diagnosis.

方法对我院636例(1262只眼)要求行LASIK手术的近视患者,将欧堡全景200激光扫描检眼镜的眼底检查结果与三面镜检查确诊结果相比较。