The precision alignment of high-performance, wide-field optical systems is generally a difficult and often laborious process. We report a new merit function regression method that has the potential to bring to such an optical alignment process higher efficiency and accuracy than the conventional sensitivity table method. The technique uses actively damped least square algorithm to minimize the Zernike coefficient-based merit function representing the difference between the designed and misaligned optical wave fronts. The application of this method for the alignment experiment of a Cassegrain type collimator of 900mm in diameter resulted in a reduction of the mean system rms wave-front error from 0.283 lambda to 0.194 lambda;, and in the field dependent wave-front error difference from +/-0.2 lambda to +/-0.014 lambda in just two alignment actions. These results demonstrate a much better performance than that of the conventional sensitivity table method simulated for the same steps of experimental alignment.
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http://dx.doi.org/10.1364/oe.15.005059 | DOI Listing |
Nat Commun
January 2025
School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China.
Stereocontrolled construction of tetrasubstituted olefins has been an attractive issue yet remains challenging for synthetic chemists. In this manuscript, alkynyl selenides, when treated with ArBCl, are subject to an exclusive 1,1-carboboration, affording tetrasubstituted alkenes with excellent levels of E-selectivity. Detailed mechanistic studies, supported by DFT calculations, elucidates the role of selenium in this 1,1-addition process.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
College of the Environment and Ecology, Xiamen University, Xiamen 361005, China; Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen 361005, China. Electronic address:
Due to the high toxicity and increasing consumption, efficient removal of phenoxyacetic acid herbicides (PAAHs) from water is imperative. In current study, a new adsorbent was prepared by modifying porous carbon derived from disused floral foam with chitosan (CS) (ACFC). Density functional theory (DFT) calculation uncovered that the amino and hydroxyl groups in the introduced CS played a critical role in the efficient adsorption of ACFC towards PAAHs.
View Article and Find Full Text PDFMolecules
January 2025
Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, School of Pharmacy, Yantai University, Yantai 264005, China.
A Cu-promoted highly chemoselective dimerization of 5-aminopyrazoles to produce pyrazole-fused pyridazines and pyrazines is reported. The protocol generates switchable products via the direct coupling of C-H/N-H, C-H/C-H and N-H/N-H bonds, with the merits of broad substrate scope and high functional group compatibility. Gram-scale experiments demonstrated the potential applications of this reaction.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Department of Chemistry, Herbert H. Lehman College, City University of New York, New York, NY 10468, USA.
Breast cancer treatment has advanced significantly, particularly for estrogen receptor-positive (ER+) tumors. Tamoxifen, an estrogen antagonist, is widely used; however, approximately 40% of patients develop resistance. Recent studies indicate that microRNAs, especially miR-155, play a critical role in this resistance.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Plant Germplasm Introduction and Testing Research Unit, USDA-ARS, Prosser, WA 99350, USA.
Developing drought-resistant alfalfa ( L.) that maintains high biomass yield is a key breeding goal to enhance productivity in water-limited areas. In this study, 424 alfalfa breeding families were analyzed to identify molecular markers associated with biomass yield under drought stress and to predict high-merit plants.
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