The present invention provides a mounting mechanism for a removable bollard, which has high flexibility and convenience for the removal and reinstallation of the bollard and the socket for inserting the bollard can be covered without having additional devices after the removal of the bollard.
[更多]
An optical pulses emitter includes a first and a second Fabry-Perot laser diodes. The first and second laser diodes have a first and second working optical wavelength band respectively, and the first and second working wavelength bands has at least an overlapped wavelength band. The emitter also inc.....
[更多]
Metal chelates are useful for improving the contrast of X-ray, ultrasound, radionuclide and magnetic resonance (MR) images. However, the metal complexes must be stable and inert so that toxicity resulting from dissociation in the body can be minimized. This invention provides 16-member ring metal ch.....
[更多]
