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Green Energy & Environment 2024年第1期9卷 114-125页

作者： Yang Zhou Qiang Zeng Hongyan He Kejia Wu Fuqiao liu Xuehui li School of Chemistry and Chemical Engineering The Guangdong Provincial Key Laboratory of Green Chemical Product TechnologyState Key Laboratory of Pulp and Paper EngineeringSouth China University of TechnologyGuangzhouGuangdong510640China CAS Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China

In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations.

关键词： lignin model compounds β-O-4 dimers Electrochemical oxidation Oxidation mechanisms Substituent effect

Deep learning-based optical aberration estimation enables offline digital adaptive optics and super-resolution imaging

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Photonics Research 2024年第3期12卷 474-484页

作者： CHANG QIAO HAOYU CHEN RUN WANG TAO JIANG YUWANG WANG DONG li Department of Automation Tsinghua UniversityBeijing 100084China Institute for Brain and Cognitive Sciences Tsinghua UniversityBeijing 100084China National Laboratory of Biomacromolecules New Cornerstone Science LaboratoryCAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China College of life Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

Optical aberrations degrade the performance of fluorescence *** adaptive optics(AO)leverages specific devices,such as the Shack–Hartmann wavefront sensor and deformable mirror,to measure and correct optical ***,conventional AO requires either additional hardware or a more complicated imaging procedure,resulting in higher cost or a lower acquisition *** this study,we proposed a novel space-frequency encoding network(SFE-Net)that can directly estimate the aberrated point spread functions(PSFs)from biological images,enabling fast optical aberration estimation with high accuracy without engaging extra optics and image *** showed that with the estimated PSFs,the optical aberration can be computationally removed by the deconvolution ***,to fully exploit the benefits of SFE-Net,we incorporated the estimated PSF with neural network architecture design to devise an aberration-aware deeplearning super-resolution model,dubbed *** demonstrated that the combination of SFE-Net and SFT-DFCAN enables instant digital AO and optical aberration-aware super-resolution reconstruction for live-cell imaging.

关键词： optics resolution enable

TiO2-Fe2TiO5 heterostructure hollow spheres enable high-performance lithium-sulfur batteries via interfacial engineering

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Rare Metals 2024年第8期43卷 4006-4012页

作者： Kai-Tao liu Hong-Qiang Wang Zhuo Chen Shi-lin Zhang Ying-Ying Song Fang liu Qiao-ling li Jiao li School of Materials Science and Engineering Shandong University of Technology College of Chemistry & Environmental Science Hebei University School of Chemical Engineering Faculty of Sciences Engineering and TechnologyUniversity of Adelaide School of Materials Science and Engineering Hebei University of Technology

The shuttle effect of lithium polysulfides between sulfur cathode and lithium anode is a notorious problem in the commercial application of lithium-sulfur ***,heterostructured TiO2-Fe2TiO5hollow spheres were proposed ... 详细信息

关键词： Polysulfides

激光粉末床熔融WC-12Co硬质合金温度场模拟

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材料工程 2024年第2期52卷 50-59页

作者：牛玉玲李晓峰赵宇霞张利刘斌白培康中北大学材料科学与工程学院太原030051 中北大学机械工程学院太原030051

结合有限元软件ANSYS建立三维有限元热模型,利用APDL命令及生死单元方法实现对高斯热源的施加和WC-12Co硬质合金打印过程的模拟,得到WC-12Co硬质合金在激光粉末床熔融(LPBF)成形过程中的温度场分布,研究不同工艺参数(激光功率、扫描速度... 详细信息

结合有限元软件ANSYS建立三维有限元热模型,利用APDL命令及生死单元方法实现对高斯热源的施加和WC-12Co硬质合金打印过程的模拟,得到WC-12Co硬质合金在激光粉末床熔融(LPBF)成形过程中的温度场分布,研究不同工艺参数(激光功率、扫描速度)对温度场分布及熔池特征的影响。结果表明:WC-12Co硬质合金在LPBF过程成形时,利用有限元能够有效模拟其成形过程。位于热源前部的等温线比尾部更为密集,温度梯度更大;而扫描路径终端边缘处熔池中心的温度最高。随着激光功率的增大和扫描速度的减小,熔池宽度、深度和长度均相应增大。通过相关实验分析不同工艺参数对晶粒尺寸的影响,发现晶粒尺寸随扫描速度的增加而减小,随激光功率的增加而增大;但过高的激光功率会引起一定的热裂纹现象发生。

关键词：激光粉末床熔融 WC-12Co 有限元温度场熔池尺寸

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儿童持续思维问卷的中文修订及其信效度检验

中国临床心理学杂志 2024年第3期32卷 601-605页

作者：徐婷张宇轩黄澜李海江上海师范大学心理学院上海200234 上海师范大学教育部“教育大数据与教育决策”实验室上海200234

目的:修订儿童持续思维问卷(perseverative thinking questionnaire-children,PTQ-C),检验其在中国儿童和青少年中的信效度。方法:对3628名儿童和青少年施测中文版PTQ-C,选取反刍思维、焦虑、抑郁量表及快乐指数作为效标,并对其中417名... 详细信息

目的:修订儿童持续思维问卷(perseverative thinking questionnaire-children,PTQ-C),检验其在中国儿童和青少年中的信效度。方法:对3628名儿童和青少年施测中文版PTQ-C,选取反刍思维、焦虑、抑郁量表及快乐指数作为效标,并对其中417名被试进行了3个月后的重测。结果:探索性因素分析和验证性因素分析均支持中文版PTQ-C的单因素模型;问卷总分与反刍思维、焦虑、抑郁均呈显著正相关,与快乐指数呈显著负相关;问卷的内部一致性系数为0.959,分半信度为0.929,三个月后的重测信度为0.610;中文版PTQ-C在青少年样本中跨性别和跨年级的形态等值性、弱等值性与强等值性均成立。结论:中文版PTQ-C具有良好的信效度和测量等值性,可以作为中国儿童和青少年重复性消极思维的有效测量工具。

关键词：重复性消极思维信度效度测量等值性

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^(252)Cf自发裂变K X射线发射与动能-电荷关系

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物理学报 2024年第14期73卷 43-50页

作者：刘超刘世龙杨毅冯晶李昱兆中国原子能科学研究院核数据重点实验室北京102413

原子核裂变后多物理量间的关联测量是认识裂变过程直接有效的实验手段,然而由于初级裂变产物准确的电荷鉴别仍面临技术困难,电荷相关的多参数研究相对匮乏.为此,通过高分辨的低能高纯锗探测器和金硅面垒探测器开展了^(252)Cf自发裂变的... 详细信息

原子核裂变后多物理量间的关联测量是认识裂变过程直接有效的实验手段,然而由于初级裂变产物准确的电荷鉴别仍面临技术困难,电荷相关的多参数研究相对匮乏.为此,通过高分辨的低能高纯锗探测器和金硅面垒探测器开展了^(252)Cf自发裂变的裂变碎片K X射线和动能的符合测量.利用K X射线可以很好地鉴别电荷数Z=39—62的裂变碎片,电荷分辨ΔZ≈0.7,K X射线产额呈现强烈的电荷相关性.借助K X射线给出了碎片平均动能和平均总动能及其分布宽度随核电荷数的分布,轻碎片动能分布具有鲜明的奇偶效应,偶Z碎片的动能比奇Z碎片的高约0.48 MeV;平均总动能在Z=52—53处达到峰值,总动能分布宽度在Z=56附近呈现凹坑,这反映了形变壳结构对断点形状的显著影响.裂变碎片K X射线发射的信息及动能-电荷关系研究可为裂变独立产额测量和裂变理论模型的检验提供必要的参考数据.

关键词：裂变碎片 K X 射线电荷鉴别碎片动能

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矿井水反渗透系统阻垢剂成分与阻垢机制

工程科学学报 2024年第6期46卷 1004-1011页

作者：李曈徐梦兰赵悦任舒阳王霄郭开祥李从举国家能源集团煤炭开采水资源保护与利用国家重点实验室北京102209 北京科技大学能源与环境工程学院北京100083

矿井水反渗透浓水中阻垢剂可以抑制Ca^(2+)、Mg^(2+)结晶沉淀导致双碱法投药量高、除硬效果差,影响后续蒸发结晶分盐效果.探究反渗透系统中阻垢剂成分及阻垢机制是实现Ca^(2+)、Mg^(2+)脱稳、解决深度除硬与零排放问题的关键.本文首先... 详细信息

矿井水反渗透浓水中阻垢剂可以抑制Ca^(2+)、Mg^(2+)结晶沉淀导致双碱法投药量高、除硬效果差,影响后续蒸发结晶分盐效果.探究反渗透系统中阻垢剂成分及阻垢机制是实现Ca^(2+)、Mg^(2+)脱稳、解决深度除硬与零排放问题的关键.本文首先测定反渗透浓水水质条件,通过超滤分级、傅里叶红外光谱(FT-IR)、紫外可见吸收光谱(UV-Vis)和三维荧光光谱(EEM)分析得出溶解性有机物主要为分子量<3 kDa且含有羧基、醇/酚羟基与不饱和烃结构的微生物代谢产物和类腐殖酸物质;根据13C和31P核磁共振(NMR)谱化学位移特征(甲基碳、季碳和C—PO_(3)H_(2)结构),确定阻垢剂主要成分为羟基乙叉二膦酸(HEDP);吸附去除88.55%总磷和38.86%COD后,双碱滴定结果表明,Ca^(2+)沉淀完全所需CO^(2)_(-3)的投加量从2845.8减少至826.8 mg·L^(-1),表明HEDP主要阻止Ca^(2+)结晶成垢;重新利用HEDP复配,CO^(2)_(-3)投加量仅增加至1626.3 mg·L^(-1),说明吸附去除的部分有机物具有一定分散作用,可以抑制溶液中Ca^(2+)结晶团聚.HEDP与溶解性有机物的协同阻垢机制,为矿井水反渗透浓水中Ca^(2+)、Mg^(2+)深度去除提供重要理论依据和调控策略.

关键词：反渗透浓水阻垢剂羟基乙叉二膦酸核磁共振阻垢机制

Synergistic oxidation-reforming of biomass for high quality syngas production based on a bifunctional catalyst

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Green Carbon 2024年第1期2卷 118-123页

作者： Tao He Dan Zhang Wenqing Chen Zeng liu Ruidong zhao Jianqing li Jingli Wu Zhiqi Wang Jinhu Wu CAS Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101China Shandong Energy Institute Qingdao 266101China Qingdao New Energy Shandong Laboratory Qingdao 266101China University of Chinese Academy of Sciences Beijing 100049China

Conventional O_(2)gasification for low-rank biomass/sludge conversion is prone to high CO_(2)concentrations in the syngas because of its high O content and low calorific *** study establishes a synergistic oxidationreforming reaction route for the conversion of low-rank carbon-containing resources into high-quality *** efficient oxidation-reforming reaction is based on the bifunctional catalyst NiO-Fe_(2)O_(3)/Al_(2)O_(3),which includes Fe_(2)O_(3) oxidation sites and NiO reforming *** temperature-programmed reduction,together with X-ray diffraction and X-ray photoelectron spectroscopy experiments,demonstrated that the two functional active sites have strong interactions with the support,leading to efficient cooperation between the oxidation reaction and reforming reaction with regards to both the reaction sequence and C/H/O element *** produced from biomass/sludge based on oxidation-reforming reactions has an extremely low CO_(2)concentration of approximately 3%,and the valid gas(CO,H_(2))concentration exceeds 95%.The valid gas yield of walnut shell reached 1452.9 mL/g,the total gas yield was 1507.2 mL/g,and the H_(2)/CO ratio was 1.02,which are all very close to the theoretical maximum values of 1553.1 mL/g and 1.01,respectively,demonstrating that the inherent CO_(2)/H_(2)O along with CH4/tar species were efficiently converted to H_(2)and CO through oxidation-reforming *** a 60-cycle test,NiO-Fe_(2)O_(3)/Al_(2)O_(3) exhibited good redox stability.

关键词： Biomass Syngas Oxidation-reforming Bifunctional Catalyst

Improving strength-ductility synchronously of Electron beam welded Ti600/Ti2AlNb joint through isothermal forging

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Progress in Natural Science:Materials International 2024年第3期34卷 532-539页

作者： Yongqiang Zhang Xiangyi Xue Guoming Zheng Jingli Zhang Huiming li Shewei Xin State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an Qin Ti Intelligent Manufacturing Technologies Co.Ltd. Northwest Institute for Nonferrous Metal Research Xi'an University of Science and Technology Avic Xi'an Aircraft Industry Group Company Ltd.

Different alloys can be flexibly combined to meet the performance needs of different parts of the compressor disc by welding process. However, achieving a good combination of dissimilar alloys with different mechanical properties has always been a research difficulty. In this work, a Ti600/Ti2AlNb joint was fabricated through electron beam welding and an isothermal forging was used to optimized its microstructure and mechanical performance. The isothermal forging process increases the ultimate tensile strength（UST） and yield strength（YS）of the Ti600/Ti2AlNb joint by ～18 %, while ～2.5 times the ductility. It is indicated that before forging, the Ti600/Ti2AlNb joint exhibits a much lower strength than that of Ti600 matrix, whereas the opposite is true after isothermal forging. The isothermal forging broken the coarse columnar grains of Ti600/Ti2AlNb joint and render to an equiaxed B2 structure in which the acicular α2and O phase are precipitated, resulting a synchronous enhancement of strength and ductility. This work may pave an effective routine for improving the comprehensive mechanical properties of dissimilar metal welding joint.

关键词： Electron beam welding Isothermal forging Mechanical performance Ti600/Ti2AlNb joint

豫西黄土高原果园生草对土壤线虫群落及结构的影响

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草地学报 2024年第1期32卷 96-104页

作者：包涵吕丹丹施赟贺雨轩赵金梦许革学李晓敏王冬河南大学生命科学学院河南开封475004 河南省灵宝市特色农业发展中心河南三门峡472500

土壤线虫是土壤生物中最丰富的后生动物,从线虫群落结构角度评价果园不同覆盖作物的土壤质量可为果园管理提供依据。2022年在黄土高原东部果园开展实验,供试品种为‘富士’苹果(Malus domestica cv. Fuji),处理包括:农田、单播毛苕子(Vi... 详细信息

土壤线虫是土壤生物中最丰富的后生动物,从线虫群落结构角度评价果园不同覆盖作物的土壤质量可为果园管理提供依据。2022年在黄土高原东部果园开展实验,供试品种为‘富士’苹果(Malus domestica cv. Fuji),处理包括:农田、单播毛苕子(Vicia sativa L.)、单播黑麦草(Lolium perenne L.)。与农田对照相比,覆盖毛苕子线虫总丰度及食细菌线虫相对丰度分别显著提高了302.33%和38.41%,植物寄生线虫与杂食和捕食线虫的相对丰度分别降低了62.18%和86.12%。覆盖黑麦草较对照处理导致杂食和捕食线虫的相对丰度降低了55.59%。土壤微生物碳含量、变形菌门相对丰度、土壤pH值、豆科生物量比例是影响线虫群落结构的主要因子。果园行间覆盖毛苕子可优化线虫群落结构,有利于果树根系的生长,建议豫西黄土高原果园生草选择豆科物种毛苕子为益。

关键词：黄土高原苹果园土壤线虫覆盖作物土壤微生物