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Electrocatalytic cleavage of a lignin β-O-4 model compound and coupling with nitrogen-containing aromatics using Prussian blue analogue-derived nickel–cobalt spinel

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Journal of Energy Chemistry 2025年第1期100卷 628-636页

作者： Yi Qi Xueying Chen Bowen Liu Xuliang Lin Xueqing Qiu Yanlin Qin Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light Industry Guangdong University of Technology Guangdong Provincial Laboratory of Chemistry and fine Chemical engineering Jieyang center Guangdong Basic research center of Excellence for Ecological Security and Green Development Guangdong University of Technology

Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great *** demonstrate the targeted synthesis and cation modulation of NiCo2O4spinel nanoboxes,synthesized via cation exchange and calcination *** catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and *** catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as *** porous architecture and polymetallic composition of the NiCo2O4spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for *** innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT *** work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.

关键词： Spinel Biomass valorization Electrocatalysis Lignin oxidation Coupling

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Effect of structural parameters of Gaussian repaired pit on light intensity distribution inside KH_2PO_4 crystal

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Chinese Physics B 2014年第8期23卷 540-547页

作者：肖勇陈明君程健廖威王海军李明全 center for Precision engineering Harbin Institute of Technology Chengdu fine optical engineering research center

KH2PO4 （KDP） crystal with excellent optical properties is a very important element of inertial confinement fusion （ICF） device. However, KDP crystal surface micro-defects severely reduce the crystal laser damage threshold, affecting the crystal service life. In this paper, Gaussian repaired pit is used to replace the crystal surface micro-defects, in order to improve the laser damage resistance of the KDP crystal with surface micro-defects. At first, the physical model of Gaussian repaired pit is built by Fourier model method, and the accuracy of the method is analyzed. It is found that the calculation error can be reduced by increasing the product of the width-period ratio and the truncation constant of the repaired pit. The calculation results about the physical model of Gaussian repaired pit show that the light intensity distribution within the crystal is symmetrical, and there are evidently enhanced light intensity regions in the crystal. Meanwhile, the maximum relative intensity inside the KDP crystal decreases gradually with the increase of the width of the Gaussian repaired pit. Secondly, the Gaussian repaired pits with different widths and the same depth of 20 μm are processed by micro-milling. Their surfaces are very smooth and present the ductile cutting state under the microscope. Finally, the laser damage threshold of the Gaussian repaired pits on the surface of the KDP crystal sample is measured by a 3 ω, 6-ns laser. The results showthat the maximum threshold of the Gaussian repaired pits is 3.12 J/cm2, which is 60% higher than the threshold of initial damage point, and the laser damage threshold increases with the increase of the width of the Gaussian repaired pit.

关键词： KH2PO4 Gaussian repaired pit Fourier modal method laser damage threshold

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Mechanism of micro-waviness induced KH_2PO_4 crystal laser damage and the corresponding vibration source

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Chinese Physics B 2012年第5期21卷 34-42页

作者：李明全陈明君安晨辉周炼程健肖勇姜伟 center for Precision engineering Harbin Institute of Technology Chengdu fine optical engineering research center

The low laser induced damage threshold of the KH2PO4 crystal seriously restricts the output power of inertial confinement *** micro-waviness on the KH2PO4 surface processed by single point diamond turning has a significant influence on the damage *** this paper,the influence of micro-waviness on the damage threshold of the KH2PO4 crystal and the chief sources introducing the micro-waviness are analysed based on the combination of the Fourier modal theory and the power spectrum density *** results indicate that among the sub-wavinesses with different characteristic spatial frequencies there exists the most dangerous frequency which greatly reduces the damage threshold,although it may not occupy the largest proportion in the original *** experimental damage threshold is basically consistent with the theoretical *** the processing parameters used,the leading frequency of micro-waviness which causes the damage threshold to decrease is between 350-1 μm-1 and 30-1 μm-1,especially between 90-1 μm-1 and 200-1 μ*** on the classification study of the time frequencies of microwaviness,we find that the axial vibration of the spindle is the chief source introducing the micro-waviness,nearly all the leading frequencies are related to the practical spindle frequency（about 6.68 Hz,400 r/min） and a special middle frequency（between 1.029 Hz and 1.143 Hz）.

关键词： laser induced damage threshold micro-waviness Fourier modal theory power spectrum density

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Subsurface defect characterization and laser-induced damage performance of fused silica optics polished with colloidal silica and ceria

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Chinese Physics B 2016年第4期25卷 413-417页

作者：何祥王刚赵恒马平 Chengdu fine optical engineering research center Chengdu 610041 China

This paper mainly focuses on the influence of colloidal silica polishing on the damage performance of fused silica optics. In this paper, nanometer sized colloidal silica and micron sized ceria are used to polish fused silica optics. The colloidal silica polished samples and ceria polished samples exhibit that the root-mean-squared （RMS） average surface roughness values are 0.7 nm and 1.0 rim, respectively. The subsurface defects and damage performance of the polished optics are analyzed and discussed. It is revealed that colloidal silica polishing will introduce much fewer absorptive con- taminant elements and subsurface damages especially no trailing indentation fracture. The 355-nm laser damage test reveals that each of the fused silica samples polished with colloidal silica has a much higher damage threshold and lower damage density than ceria polished samples. Colloidal silica polishing is potential in manufacturing high power laser optics.

关键词： polishing laser-induced damage fused silica colloidal silica

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High laser damage threshold coatings and damage testing technology

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光学精密工程 2005年第4期13卷 500-504页

作者： MA Ping HU Jian-ping CHEN Song-lin TANG Ming WANG Zhen LI Wei XU Qiao Chengdu fine optical engineering research center Chengdu 610041China

The laser-induced damage threshold(LIDT) of optical coating is a limited factor for development of a high peak power laser. The automatic damage testing facility was built to determine the LIDT of optics at 1 064 nm and 355 nm.. The cleanning and processing procedure of the substrate and coating technique were improved, and the damage resistance of high-reflective coating at 1 064 nm was increased.

关键词：激光涂覆技术 LIDT 自动机械光学仪器激光仪器

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Correlation of polishing-induced shallow subsurface damages with laser-induced gray haze damages in fused silica optics

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Chinese Physics B 2016年第8期25卷 421-425页

作者：何祥赵恒王刚周佩璠马平 Chengdu fine optical engineering research center Chengdu 610041 China

Laser-induced damage in fused silica optics greatly restricts the performances of laser facilities. Gray haze damage,which is always initiated on ceria polished optics, is one of the most important damage morphologies in fused silica *** this paper, the laser-induced gray haze damages of four fused silica samples polished with CeO2, Al2O3, ZrO2, and colloidal silica slurries are investigated. Four samples all present gray haze damages with much different damage ***, the polishing-induced contaminant and subsurface damages in four samples are analyzed. The results reveal that the gray haze damages could be initiated on the samples without Ce contaminant and are inclined to show a tight correlation with the shallow subsurface damages.

关键词： laser-induced damage polishing subsurface damage fused silica

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Improvement of laser damage thresholds of fused silica by ultrasonic-assisted hydrofluoric acid etching

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Chinese Physics B 2017年第11期26卷 510-514页

作者：李源严鸿维杨科姚彩珍王志强闫春燕邹鑫书袁晓东杨李茗巨新 University of Science and Technology Beijing Department of Physics China Academy of engineering Physics Laser Fusion Research Center fine optical engineering research center

Polished fused silica samples were etched for different durations by using hydrofluoric（HF） acid solution with HF concentrations in an ultrasonic field. Surface and subsurface polishing residues and molecular structure parameters before and after the etching process were characterized by using a fluorescence microscope and infrared（IR） spectrometer, respectively. The laser induced damage thresholds（LIDTs） of the samples were measured by using pulsed nanosecond laser with wavelength of 355 nm. The results showed that surface and subsurface polishing residues can be effectively reduced by the acid etching process, and the LIDTs of fused silica are significantly improved. The etching effects increased with the increase of the HF concentration from 5 wt.% to 40 wt.%. The amount of polishing residues decreased with the increase of the etching duration and then kept stable. Simultaneously, with the increase of the etching time, the mechanical strength and molecular structure were improved.

关键词： HF etching fused silica laser induced damage threshold infrared spectra

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Contamination process and laser-induced damage of HfO_2/SiO_2 coatings in vacuum

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Chinese Optics Letters 2009年第7期7卷 643-645页

作者：马平潘峰陈松林王震胡建平张清华邵建达 Shanghai Institute of Optics and fine Mechanics Chinese Academy of Sciences Chengdu fine optical engineering research center Graduate University of Chinese Academy of Sciences

The performances of HfO2/SiO2 single- and multi-layer coatings in vacuum influenced by contamination are studied. The surface morphology, the transmittance spectrum, and the laser-induced damage threshold are investigated. The results show that the contamination in vacuum mainly comes from the vacuum system and the contamination process is different for the HfO2 and SiO2 films. The laser-induced damage experiments at 1064 nm in vacuum show that the damage resistance of the coatings will decrease largely due to the organic contamination.

关键词： Coatings Hafnium compounds Laser damage Lasers Silicon compounds Vacuum

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Full-band error control and crack-free surface fabrication techniques for ultra-precision fly cutting of large-aperture KDP crystals

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Frontiers of Mechanical engineering 2017年第2期12卷 193-202页

作者： F. H. ZHANG S. F. WANG C. H. AN J. WANG Q. XU Department of Mechanical engineering Harbin Institute of TechnologyHarbin 150001 China Chengdu fine optical engineering research center Chengdu 610041China

Large-aperture potassium dihydrogen phos- phate （KDP） crystals are widely used in the laser path of inertial confinement fusion （ICF） systems. The most common method of manufacturing half-meter KDP crystals is ultra-precision fly cutting. When processing KDP crystals by ultra-precision fly cutting, the dynamic characteristics of the fly cutting machine and fluctuations in the fly cutting environment are translated into surface errors at different spatial frequency bands. These machin- ing errors should be suppressed effectively to guarantee that KDP crystals meet the full-band machining accuracy specified in the evaluation index. In this study, the anisotropic machinability of KDP crystals and the causes of typical surface errors in ultra-precision fly cutting of the material are investigated. The structures of the fly cutting machine and existing processing parameters are optimized to improve the machined surface quality. The findings are theoretically and practically important in the development of high-energy laser systems in China.

关键词： ultra-precision fly cutting large-aperture KDP crystals spatial frequency processing error

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Improved partial response maximum likelihood method combining modulation code for signal waveform modulation multi-level disc

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Chinese Physics B 2014年第10期23卷 213-219页

作者：王鹤群裴京潘龙法 optical Memory National engineering research center Tsinghua University

In this paper, we describe an improved adaptive partial response maximum likelihood （PRML） method combining modulation code tbr signal waveform modulation multi-level disc. This improved adaptive PRML method employs partial response equalizer and adaptive viterbi detector combining modulation code. Compared with the traditional adaptive PRML detector, the improved PRML detector additionally employs illogical sequence detector and corrector. Illogical sequence detector and corrector can aw）id the appearance of illogical sequences effectively, which do not follow the law of modulation code for signal waveform modulation multi-level disc, and obtain the correct sequences. We implement the improved PRML detector using a DSP and an FPGA chip. The experimental results show good performance. The higher efficient and lower complexity can be obtained by using the improved PRML method than by using the previous PRML method. Meanwhile, resource utilization of the improved PRML detector is not changed, but the bit error rate （BER） is reduced by more than 20%.

关键词： multi-level disc signal waveform modulation viterbi detector partial response maximum likeli-hood

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