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Unveiling the promotion role of ZnO on Zn-Al spinel oxide for CO2 hydrogenation

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Journal of Energy Chemistry 2025年第1期100卷 18-25页

作者： Tongyao Wang Xinlong Yao Lixin Liang Hongyu Chen Pan gao Guangjin Hou State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The Zn-Al spinel oxide stands out as one of the most active catalysts for high-temperature methanol synthesis from CO2hydrogenation. However, the structure–activity relationship of the reaction remains poorly understood due to challenges in atomic-level structural characterizations and analysis of reaction intermediates. In this study, we prepared two Zn-Al spinel oxide catalysts via coprecipitation（ZnAl-C）and hydrothermal（ZnAl-H） methods, and conducted a comparative investigation in the CO2hydrogenation reaction. Surprisingly, under similar conditions, ZnAl-C exhibited significantly higher selectivity towards methanol and DME compared to ZnAl-H. Comprehensive characterizations using X-ray diffraction（XRD）, Raman spectroscopy and electron paramagnetic resonance（EPR） unveiled that ZnAl-C catalyst had abundant ZnO species on its surface, and the interaction between the ZnO species and its ZnAl spinel oxide matrix led to the formation of oxygen vacancies, which are crucial for CO2adsorption and activation. Additionally, state-of-the-art solid-state nuclear magnetic resonance（NMR） techniques,including ex-situ and in-situ NMR analyses, confirmed that the surface ZnO facilitates the formation of unique highly reactive interfacial formate species, which was readily hydrogenated to methanol and DME. These insights elucidate the promotion effects of ZnO on the ZnAl spinel oxide in regulating active sites and reactive intermediates for CO2-to-methanol hydrogenation reaction, which is further evidenced by the significant enhancement in methanol and DME selectivity observed upon loading ZnO onto the ZnAl-H catalyst. These molecular-level mechanism understandings reinforce the idea of optimizing the ZnO-ZnAl interface through tailored synthesis methods to achieve activity-selectivity balance.

关键词： Reaction intermediates

Channel pruning on frequency response

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Science China(Information Sciences) 2025年第1期68卷 159-170页

作者： Hang LIN Yifan PENG Lin BIE Chenggang YAN Xibin ZHAO Yue gao School of Software Tsinghua University School of Automation Hangzhou Dianzi University

Network pruning has a significant role in reducing network parameters and accelerating the inference time of the network. Some existing methods prune the network based on the frequency of the data, and finally obtain a sub-network with high accuracy. However, according to our experimental analysis, different frequencies of information in the data contribute differently to the accuracy of the model, and using this information directly for pruning without making a selection will lead to incorrect results. We believe that pruning should retain the convolutional kernels in the network that process important information, while those kernels that process unimportant information should be removed. In this paper, we first investigate the meaning of each frequency band information in the spectrum and their contribution to the prediction accuracy of the network,and according to these results, we propose a new pruning method based on frequency response(PFR). Our PFR finds and removes the convolutional kernels in the network that specialize in processing unimportant information, resulting in a compact neural network model. PFR obtains significant experimental results on different datasets, for example, a 56.0% raduction of float points operations(FLOPs) on Res Net-50 and only 0.37% of Top-1 accuracy degradation on the Image Net dataset.

关键词： deep learning model compression filter pruning channel pruning frequency response

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基于偏最小二乘法的乌头碱类化合物毒性的定量构效关系研究

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计算机与应用化学 2011年第6期28卷 765-768页

作者：李佐静王琳闫心丽高志祥孟繁浩沈阳药科大学基础学院辽宁沈阳110016 中国医科大学药学院辽宁沈阳110001

乌头碱类化合物属于二萜类生物碱,存在于乌头属欧乌头、川乌、北草乌和华乌头等多种毛茛科植物中,该类化合物既是其活性成分,也是其毒性成分。利用化合物定量结构-毒性效应关系（QSTR）方法研究了14个乌头碱类化合物的各种量化参数对其... 详细信息

乌头碱类化合物属于二萜类生物碱,存在于乌头属欧乌头、川乌、北草乌和华乌头等多种毛茛科植物中,该类化合物既是其活性成分,也是其毒性成分。利用化合物定量结构-毒性效应关系（QSTR）方法研究了14个乌头碱类化合物的各种量化参数对其毒性的影响,并建立了毒性预测模型。由于该类化合物是从中药中提取分离的生物碱,样本数量相对较少,本文采用了偏最小二乘回归方法（PLS）进行降维,进行4个成分的提取及建模。毒性预测模型为：Log（toxi）=0.1593^＊Mass＋0.2908^＊LogP＋1.5475^＊SAA-0.5222^＊SAG-0.6104^＊Volume＋0.3112^＊Ref＋0.1784^＊Polar＋0.1785^＊BE＋0.1634^＊HF-0.1387^＊Dipole＋0.1412,结果表明该模型具有较好的毒性预测能力。

关键词：乌头碱类化合物构效关系偏最小二乘法毒性预测

An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： Lingxiao Li Jing Li Yanqi Song Sujuan Qin Qiaoyan Wen Fei gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing

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SMD石英晶体八点胶抗振设计

^(18)F-FDG PET/CT联合血清糖类抗原125及miR-143在宫颈癌患者术后复发/转移中的诊断价值

中国科技纵横 2021年第23期 57-59页

作者：李冬强姜凡高志祥南京中电熊猫晶体科技有限公司江苏南京 210038

SMD石英晶体是利用石英的压电效应制成的一种表贴型频率元器件,主要由基座、石英振子、银胶、盖板4部分组成,其中银胶起着导电及固定石英振子的作用,广泛采用两点胶、四点胶技术.本文介绍了通过增加银胶点胶个数来提升石英晶体抗振性能... 详细信息

SMD石英晶体是利用石英的压电效应制成的一种表贴型频率元器件,主要由基座、石英振子、银胶、盖板4部分组成,其中银胶起着导电及固定石英振子的作用,广泛采用两点胶、四点胶技术.本文介绍了通过增加银胶点胶个数来提升石英晶体抗振性能的设计及相关对比验证试验,试验结果表明八点胶设计显著提升了石英晶体的抗振性能.

关键词：石英晶体抗振石英振子银胶八点胶

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中华实用诊断与治疗杂志 2023年第10期37卷 987-992页

作者：刘林何莎莎高志翔郑州大学附属洛阳中心医院影像科河南洛阳471000

目的观察宫颈癌患者血清糖类抗原125(CA125)、miR-143表达情况,探讨^(18)F-FDG PET/CT联合血清CA125、miR-143检测对宫颈癌患者术后复发/转移的诊断价值。方法2018年1月—2022年1月郑州大学附属洛阳中心医院诊治宫颈癌患者90例,均行宫... 详细信息

目的观察宫颈癌患者血清糖类抗原125(CA125)、miR-143表达情况,探讨^(18)F-FDG PET/CT联合血清CA125、miR-143检测对宫颈癌患者术后复发/转移的诊断价值。方法2018年1月—2022年1月郑州大学附属洛阳中心医院诊治宫颈癌患者90例,均行宫颈癌根治术,术后均定期行^(18)F-FDG PET/CT检查并测定最大标准摄取值,采用放射免疫法检测血清CA125水平,采用实时荧光定量PCR法检测血清miR-143相对表达量。以术后随访结果为金标准,计算^(18)F-FDG PET/CT、血清CA125及miR-143诊断宫颈癌患者术后复发/转移的灵敏度、特异度、准确率,比较三者联合与任意二者联合诊断宫颈癌患者术后复发/转移的灵敏度、特异度、准确率。绘制ROC曲线,评估^(18)F-FDG PET/CT、血清CA125及miR-143诊断宫颈癌患者术后复发/转移的效能。结果血清CA125诊断宫颈癌患者术后复发/转移的灵敏度为45.1%,特异度为30.8%,准确率为38.9%;血清miR-143诊断宫颈癌患者术后复发/转移的灵敏度为49.0%,特异度为30.8%,准确率为41.1%;^(18)F-FDG PET/CT诊断宫颈癌患者术后复发/转移的灵敏度为72.5%,特异度为41.0%,准确率为58.9%。^(18)F-FDG PET/CT+CA125+miR-143诊断宫颈癌患者术后复发/转移的灵敏度(98.0%)、特异度(94.9%)、准确率(96.7%)均高于CA125+miR-143(52.9%、30.8%、43.3%)、^(18)F-FDG PET/CT+CA125(78.4%、61.5%、71.1%)、^(18)F-FDG PET/CT+miR-143(80.4%、66.7%、74.4%)(P<0.05)。最大标准摄取值、血清CA125、miR-143相对表达量分别以7.40、30.43 u/mL、37.78为最佳截断值,单独及三者联合诊断宫颈癌患者术后复发/转移的AUC分别为0.974(95%CI:0.950~0.998,P<0.001)、0.749(95%CI:0.679~0.820,P<0.001)、0.831(95%CI:0.767~0.895,P<0.001)、0.999(95%CI:0.998~1.000,P<0.001),三者联合诊断的AUC均大于单独诊断(P<0.05),三者联合诊断宫颈癌患者术后复发/转移的灵敏度为98.0%,特异度为94.9%。结论^(18)F-FDG PET/CT、血清CA125及miR-143联合对宫颈癌患者术后复发/转移有较高诊断价值。

关键词：宫颈癌 ^(18)F-氟代脱氧葡萄糖PET/CT 糖类抗原125 miR-143 复发转移

The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 275-282页

作者： gao Qian LI Jun WANG Xianhui CAO Laifu GONG Jian LI Bo Central Iron and Steel Research Institute Group Beijing 100081China Shougang Zhixin Electromagnetic Material R&D(Beijing)Co. Ltd.Beijing 101300China Beijing Shougang Co. Ltd.Qian’an 064404China

Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were *** illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically *** effect of precipitate ripening on the Goss texture and magnetic property was *** indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate *** recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}oriented grains growing abnormally and a magnetic induction intensity of ***,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss ***,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 *** a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this *** heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.

关键词： high temperature annealing heating rate secondary recrystallization grain oriented silicon steel

Unlocking the potential of spatial transcriptomics with custom microfluidic chips

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Science China Life Sciences 2025年

作者： Bingqi Wu Yuan gao China National Center for Bioinformation Beijing Institute of Genomics Chinese Academy of Sciences University of Chinese Academy of Sciences

Spatial transcriptomics technique detects RNA sequences (St?hl et al.,2016) and quantifies their expression in the positional context (Ke et al.,2013),which can provide important information such as cell heterogeneity,cell developmental trajectory,differential gene expression between tissue regions or *** date,it is becoming a powerful tool for exploring tumorigenesis (Ren et al.,2023),cerebral neurodevelopment (Shi et al.,2023),embryonic development(Arutyunyan et al.,2023),and other biological ***-dimensional(3D) spatial transcriptome typically requires stacking multiple tissue slices to obtain a 3D atlas (Schott et al.,2024);therefore it prefers a method that meets high throughput,large sample sizes,and affordable cost to cover large regions of the ***,the lack of a single method that meets all of these requirements limits large-scale application of 3D spatial transcriptomics.

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高压下陶瓷空封光电耦合器内部气体放电电流特性研究

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半导体光电 2019年第4期40卷 476-479页

作者：刘正松高智翔丁鹏陈春霞唐塽赵瑞莲中航工业航空动力控制系统研究所江苏无锡214036 重庆光电技术研究所重庆400060

陶瓷空封光电耦合器存在高压下的内部气体放电,分析其放电电流特性有助于器件可靠性研究。提出了基于体电流和气体放电电流的陶瓷空封光电耦合器漏电流模型,并针对高压下漏电流测试能力不足的现状,设计了基于悬浮供电的漏电流检测系统,... 详细信息

陶瓷空封光电耦合器存在高压下的内部气体放电,分析其放电电流特性有助于器件可靠性研究。提出了基于体电流和气体放电电流的陶瓷空封光电耦合器漏电流模型,并针对高压下漏电流测试能力不足的现状,设计了基于悬浮供电的漏电流检测系统,通过对高压下器件漏电流的测试及对比分析,实现了对内部气体放电电流特性的定量评估。

关键词：高压陶瓷空封光电耦合器气体放电电流