一种多螺距螺杆和多螺距螺母的组合及多螺距螺母的制造方法,由沿着螺线进行一转期间具有螺纹牙的缺省区间的多螺距螺杆,和内螺纹的螺纹牙沿着螺旋线一转期间螺旋升角平缓的区间和螺旋升角急升的区间交替出现,并且相互连续地形成的多螺距螺母构成,多螺距螺杆的螺纹牙仅由螺旋升角为零的区间形成,并且当螺杆的螺纹牙的齿...
Building a Sustainable Water Management System in the Republic of Serbia: Challenges and Issues Climate change, disproportional water distribution, extensive overuse, and anthropogenic contamination of water resources have limited the access to clean water for a large portion of the population on this ...