With the rapid development of micro-optical applications, there is an increasing demand for micro-optical elements that can be made with minimal processing steps. Current research focuses on practical functionalities of optical performance, lightweight, miniaturization, and easy integration. As an important planar diffractive optical element, the Fresnel zone plate (FZP) provides a compact solution for focusing and imaging.
View Article and Find Full Text PDFMicromachines (Basel)
August 2022
The strong nonlinear absorption effect and “cold” processing characteristics of femtosecond lasers make them uniquely advantageous and promising for the micro- and nanoprocessing of hard and brittle materials, such as quartz. Traditional methods for studying the effects of femtosecond laser parameters on the quality of the processed structure mainly use univariate analysis methods, which require large mounts of experiments to predict and achieve the desired experimental results. The method of design of experiments (DOE) provides a way to predict desirable experimental results through smaller experimental scales, shorter experimental periods and lower experimental costs.
View Article and Find Full Text PDFWe propose a high-precision method for the fabrication of variable focus convex microlens arrays on K9 glass substrate by combining femtosecond laser direct writing and hot embossing lithography. A sapphire master mold with a blind cylindrical hole array was prepared first by femtosecond laser ablation. The profile control of microlenses dependent on the temperature and the diameter of the blind hole in the sapphire mold was investigated.
View Article and Find Full Text PDFMaterials (Basel)
October 2018
ZrB₂⁻HfC ceramics have been fabricated using the liquid phase sintering technique at a sintering temperature as low as 1750 °C through the addition of Ni. The effects of HfC addition on the microstructure and mechanical properties of ZrB₂⁻based ceramics have been investigated. These ceramics were composed of ZrB₂, HfC, Ni, and a small amount of possible (Zr, Hf)B₂ solid solution.
View Article and Find Full Text PDFObjective: To investigate the effect of combination of dexmedetomidine and sufentanil on patient-controlled intravenous analgesia (PCIA) in patients after abdominal operation and to assess the safety and validity of this treatment.
Methods: This is a prospective, randomized controlled, blinded, multicenter clinical study. A total of 210 patients from 9 clinical research centers underwent selective abdominal operation with general anesthesia were enrolled in the study, including laparoscopic-assisted abdominal operation on stomach, intestines or open surgery on stomach, intestines, kidneys and liver, the American Society of Anesthesiologists status I to II.
Aims: To test the hypothesis that uridine 5'-triphosphate (UTP) had a protective effect on cerebral ischemia reperfusion (IR) injury in rats.
Methods: Ischemia was induced by intraluminal suture of middle cerebral artery occlusion (MCAO). UTP solution was delivered through an indwelling tail venous catheter via microinfusion pump 30 min after the occlusion of MCA at a rate of 0.