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Chalcohalide glasses with a gradient refractive index (GRIN) microstructure were imprinted by microthermal poling for realizing diffractive optical elements covering the visible to middle-infrared wavelength range. The effect of halogen ions on the saturation poling voltage (U), surface profile, diffraction pattern, optical transmittance, GRIN microstructure, and structural rearrangement of poled glass is investigated. An effective imprinting formation region for a GRIN microstructure based on the U and glass composition is observed under fixed poling time and temperature. The onset U (60 V–150 V) and activation energy of mobile cations (0.449 eV–0.533 eV) decreases with the atomic number of the halogen from F to I, but the saturation diffractive order (8th to 11th levels) and phase difference (~0.08λ to 0.18λ) increases accordingly. The onset U and activation energy decrease with the deformability of the glass network and radius of the halogen ions. The phase difference and saturation diffractive orders decrease with the proportion and electronegativity of interval halogen atoms in the glass network. Thus, chalcohalide glasses with GRIN microstructures can be tailored by adjusting the type of halogen ions for realizing various diffraction optical elements.

A dual-fiber point diffraction interferometer is built to measure the wavefront aberration of an imaging system with high precision. The optical intensity of the test light and reference light are controlled independently, so that high interference contrast can be obtained. The interferometer has several advantages: high precision, a flexible structure, and a quasi-common optical path. System errors of the interferometer that influence the measurement accuracy are considered and calibrated. In the experiments, a projection lens with numerical aperture of 0.3 is measured. The measured wavefront error is 1.5 nm rms, and the measurement repeatability is 35 pm rms.

A gradient refractive index (GRIN) microstructure covering visible to middle infrared wavelength is imprinted in chalcohalide glass through a simple and inexpensive microthermal poling process. The effects of poling voltage (U), temperature (T), and time (t) on diffraction, morphology, elemental distribution and transmittance of the glass are thoroughly investigated. An effective imprinting formation region of GRIN microstructure based on the U and T values is observed under a fixed t of 30 min. Deformation of morphology and diffraction order increase with increasing U and T saturated at approximately 750 V and 150 °C respectively. The process can be divided into three stages, adding voltage, maintaining voltage and decreasing temperature. During the front two stages, K+ ions depletion layer forms in subsurface of sample anode-side, accompanied by the transformation of homopolar bonds Ga–Ga and S–S into heteropolar bond Ga–S. Moreover, most parts of K+ ions migrate back to the depletion layer during the last stage.

We propose a noncontact method for measuring the cone angle of an axicon. A microscanning stage moves the axicon being tested while a Fizeau interferometer is recording the scanning interferograms. The cone angle is measured accurately with the axial moving distance and the phase change calculated from interference fringe counting. Numerical analysis discusses the influence of standard deviation of the interference fringe count and the standard deviation of the scanning distance. Three methods for systematic error calibration are also proposed. This approach can measure both concave and convex axicons with a cone angle in the range of 96.4 deg to 170 deg. The measurable diameter of the axicon exceeds 100 mm. The spatial distribution of cone angle can be obtained with a resolution from 300 μm to 1 mm. The theoretical measurement accuracy is better than 10″ when the scanning distance is 1000 μm, and the positioning error is

Phytohemagglutin (PHA), purified from red kidney beans (Phaseolus vulgaris) by Affi-Gel blue affinity chromatography, was subjected to ultrahigh-pressure (UHP) treatment (150, 250, 350, and 450 MPa). The purified PHA lost its hemagglutination activity after 450 MPa treatment and showed less pressure tolerance than crude PHA. However, the saccharide specificity and α-glucosidase inhibition activity of the purified PHA did not change much after UHP treatment. Electrophoresis staining by periodic acid-Schiff (PAS) manifested that the glycone structure of purified PHA remained stable even after 450 MPa pressure treatment. However, electrophoresis staining by Coomassie Blue as well as circular dichroism (CD) and differential scanning calorimetry (DSC) assay proved that the protein unit structure of purified PHA unfolded when treated at 0-250 MPa but reaggregates at 250-450 MPa. Therefore, the hemagglutination activity tends to be affected by the protein unit structure, while the stability of the glycone structure contributed to the remaining α-glucosidase inhibition activity.

Dictyophora indusiata polysaccharide (DP1) was successfully chelated with zinc chloride to achieve its enhanced antiproliferative activity. The obtained DP1-Zn complex showed significant antiproliferative activity (18.1 ± 2.84% viability of MCF-7 cells at 250 μg/mL) on a group of human cancer cell lines through induction of apoptosis. The pro-apoptotic action of DP1-Zn was confirmed by morphological changes including chromatin condensation, DNA breakage, and S phase cell cycle arrest in human breast adenocarcinoma cells (MCF-7). The DP1-Zn-induced apoptotic pathways were characterized by the activation of caspases-3, -8, and -9, mitochondrial dysfunction, and reactive oxygen species (ROS) overproduction (305 ± 7.06% production of control at 250 μg/mL). This study suggested that DP1-Zn can be developed as a candidate for cancer treatment and prevention, especially human breast adenocarcinoma.

Nonflatness of stage mirror surface affects the position accuracy of the wafer stage in lithography tool. Precise surface flatness measurement is needed for the computer controlled polishing of stage mirror. A subaperture stitching system using a commercial 4-inch Fizeau interferometer was presented in this paper. Absolute test was used to calibrate the surface figure of the reference mirror with the accuracy better than λ/100 PV (λ = 632.8nm）. Subaperture stitching was used to extend the measurement aperture larger than 450×50mm. Stitching measurements were carried out for stage mirrors during surface polishing. Comparison tests were also made with a 24-inch interferometer. The results show that the stitching system has the advantages of larger dynamic range, higher spatial resolution, and better measurement accuracy in local area.