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Screening current in ultra-high-field non-insulated superconducting magnets

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Science China(Technological Sciences) 2024年第7期67卷 2255-2273页

作者： ZHOU BenZhe WANG Lei CHEN Yong WANG QiuLiang WANG KangShuai zhang zili LIU JianHua University of Chinese Academy of Sciences Beijing 100049China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China

Screening current is recognized as one of the critical elements limiting the progression of superconducting magnets toward achieving higher magnetic fields. Currently, most non-insulated(NI) superconducting magnets consider the magnet as insulated when addressing the issue of screening current. However, the bypass current in the NI magnet can modify the actual history of magnetization, so the screening current in NI magnet will be different from that in the insulated magnet. This paper presents a novel method based on the homogenized T-A formulation(T is the current vector potential, and A is the magnetic vector potential), which enables real-time simulation of both the bypass current behavior and the implications of screening current in NI superconducting magnets, even when these magnets contain tens of thousands of turns. We have developed a 32 T NI hybrid superconducting magnet and validated the effectiveness of this method through experiments. Employing this efficacious method,we conducted a comprehensive calculation of screening current in NI magnets, comparing them with insulated magnets in terms of screening current-induced stress(SCIS), screening current-induced field(SCIF), and losses. The results indicate that in the NI insert coils, the sequential excitation of background coils and insert coils induces a reverse screening current, resulting in slightly lower SCIF and SCIS compared to those in the insulated magnets. The method and results can contribute to the enhancement of magnet design and provide valuable insights for the development of ultra-high fields(UHF) NI magnets.

关键词： ultra-high-field superconducting magnet screening current REBCO coil NI coil stress loss

Artesunate Induces Ferroptosis in Hepatic Stellate Cells and Alleviates Liver Fibrosis via the ROCK1/ATF3 Axis

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Journal of Clinical and Translational Hepatology 2024年第1期12卷 36-51页

作者： Yingqian Wang Yujia Li Yangling Qiu Min Shen Ling Wang Jiangjuan Shao Feng zhang Xuefen Xu zili zhang Mei Guo Shizhong Zheng Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica Nanjing University of Chinese MedicineNanjingJiangsuChina Institute of Translational Medicine Medical CollegeYangzhou UniversityYangzhouJiangsuChina Jiangsu Key Laboratory of Therapeutic Material of Chinese Medicine Nanjing University of Chinese MedicineNanjingJiangsu China

Background and Aims:Development of fibrosis in chronic liver disease requires activation of hepatic stellate cells(HSCs)and leads to a poor ***(Art)is an ester derivative of artemisinin that can induce ferroptosis in HSCs,and activated transcriptional factor 3(ATF3)is an ATF/CREB transcription factor that is induced in response to *** this study,we examined the role of the Rho-associated protein kinase 1(ROCK1)/ATF3 axis in Art-induced ferroptosis in ***:HSC activation and ferroptosis were studied in vitro by western blotting,polymerase chain reaction,immunofluorescence,and other ***3 electrophoretic mobility and ROCK1 protein stability were assayed by western *** was used to detect the interaction of ROCK1 and ATF3,as well as ATF3 phosphorylation.A ubiquitination assay was used to verify ROCK1 ***3-interfering and Rock1-overexpressing mice were constructed to validate the anti-hepatic fibrosis activity of Art in ***:Art induced ferroptosis in HSCs following glutathione-dependent antioxidant system inactivation resulting from nuclear accumulation of unphosphorylated ATF3 mediated by ROCK1-ubiquitination in *** also decreased carbon tetrachloride-induced liver fibrosis in mice,which was reversed by interfering with Atf3 or overexpressing ***:The ROCK1/ATF3 axis was involved in liver fibrosis and regulation of ferroptosis,which provides an experimental basis for further study of Art for the treatment of liver fibrosis.

关键词： Ferroptosis Liver fibrosis Antioxidant system ATF3 ROCK1

Achievement of a high-performance 30-tesla metal-as-insulated user superconducting magnet

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Science China(Technological Sciences) 2024年第6期67卷 1974-1978页

作者： ZHOU BenZhe DAI YinMing zhang zili LIU Hui WANG YaoHui WANG Lei WANG Hui CHEN ShunZhong WANG KangShuai CHEN Yong LIU JianHua WANG QiuLiang Institute of Electrical Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

Strong magnetic fields can be used to manipulate the states of matter and induce unique ***,they enable a thorough investigation of the intrinsic properties of matter through the application of the nuclear magnetic resonance(NMR)*** versatile nature of strong magnetic fields facilitates the discovery of novel phenomena and patterns.

关键词： effect NMR versatile

A comprehensive review of dwell time optimization methods in computer-controlled optical surfacing

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Light(Advanced Manufacturing) 2024年第3期5卷 142-171页

作者： Tianyi Wang Xiaolong Ke Lei Huang Qingqing Cui zili zhang Chunjin Wang Hyukmo Kang Weslin Pullen Heejoo Choi Daewook Kim Vipender Negi Qian Kemao Yi Zhu Stefano Giorgio Philip Boccabella Nathalie Bouet Corey Austin Mourad Idir National Synchrotron Light Source II(NSLS-II) Brookhaven National LaboratoryP.O.Box 5000UptonNY 11973USA School of Mechanical and Automotive Engineering Xiamen University of TechnologyXiamen 361024China State Key Laboratory of Ultra-precision Machining Technology Department of Industrial Systems and EngineeringThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina James C.Wyant College of Optical Sciences University of Arizona1630 E.University Blvd.P.O.Box 210094TucsonAZ 85721-0094USA Large Binocular Telescope Observatory University of ArizonaTucsonAZ 85721USA Department of Astronomy and Steward Observatory University of Arizona933 N.Cherry Ave.TucsonAZ85721USA Indian Institute of Technology Delhi Hauz KhasNew Delhi 110016India School of Computer Science and Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798

Dwell time plays a vital role in determining the accuracy and convergence of the computer-controlled optical surfacing ***,optimizing dwell time presents a challenge due to its ill-posed nature,resulting in non-unique *** address this issue,several well-known methods have emerged,including the iterative,Bayesian,Fourier transform,and matrix-form *** their independent development,these methods share common objectives,such as minimizing residual errors,ensuring dwell time's positivity and smoothness,minimizing total processing time,and enabling flexible dwell *** paper aims to comprehensively review the existing dwell time optimization methods,explore their interrelationships,provide insights for their effective implementations,evaluate their performances,and ultimately propose a unified dwell time optimization methodology.

关键词： Dwell time optimization Computer-controlled optical surfacing Finishing Polishing Optical fabrication

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有机液体载氢储运技术研究进展及应用场景

储能科学与技术 2024年第2期13卷 643-651页

作者：邢承治赵明尚超张思婧张自力刘杨中化学建设投资集团科技产业发展有限公司中化学建设投资集团有限公司北京102308

在“双碳”战略目标背景下,氢能产业在深度和广度上都获得了高速发展,上游制氢资源丰富,下游用氢市场广阔,由于跨地区氢能供需失衡,中游氢能储运已经成为氢能产业链的短板,严重制约了氢能产业的进一步发展。在这种情况下,有机液体载氢(L... 详细信息

在“双碳”战略目标背景下,氢能产业在深度和广度上都获得了高速发展,上游制氢资源丰富,下游用氢市场广阔,由于跨地区氢能供需失衡,中游氢能储运已经成为氢能产业链的短板,严重制约了氢能产业的进一步发展。在这种情况下,有机液体载氢(LOHC)储运技术应运而生,以一种化学储氢方式完美克服了高压气态储氢、低温液态及固态等物理储氢方式的缺陷。与其他氢能储运技术相比,LOHC储运技术在安全、成本、技术、效率等方面具有突出的优势,有望补齐氢能储运的短板,完善氢能产业链。本文对三种主要LOHC储运技术,从工艺原理、储氢载体、综合成本、科研发展等方面进行比较分析。认为甲苯、N-乙基咔唑和二苄基甲苯等三种LOHC储运技术已完成了理论研究、实验验证及中试放大等工作,技术趋于完善,具备了工业化推广应用的条件。在未来展望角度上,对包括大型氢能储运基地和分布式脱氢加氢一体化站在内的两种LOHC储运技术的新型应用场景进行了分析,并梳理了目前LOHC储运技术研究面临的问题和研究方向,并提出了希望和建议。

关键词：氢能有机液体载氢(LOHC) 储运应用场景

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METTL3通过IGF2BP2依赖性方式参与m6A修饰调控HBV复制的机制

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陆军军医大学学报 2024年第5期46卷 442-449页

作者：余玲张自力曾蓉张节王鹏潘万龙川北医学院基础医学与法医学院四川南充637100 川北医学院附属医院老年科四川南充637100

目的探究胰岛素样生长因子2 mRNA结合蛋白2(insulin like growth factor 2 mRNA binding protein 2,IGF2BP2)协助甲基转移酶样3(methytransferase like 3,METTL3)通过N6-甲基腺苷(N6-methyladenosine,m6A)修饰调控HBV复制的分子机制。方法以HBV稳定复制细胞系HepG2.2.15及其亲本细胞HepG2为模型,斑点杂交分析m6A修饰水平,RT-qPCR和Western blot检测METTL3、IGF2BP2表达。生物信息学及免疫共沉淀分析METTL3与m6A阅读蛋白及其相互作用。将METTL3质粒、METTL3 siRNA和(或)IGF2BP2 siRNA转染至HepG2.2.15细胞,分别记为OE-METTL3、si-METTL3、si-IGF2BP2、OE-METTL3+si-IGF2BP2、si-METTL3+si-IGF2BP2、Control组;qPCR检测HBV DNA、HBV rcDNA、HBV cccDNA拷贝数,RT-qPCR或Western blot检测HBV pgRNA、METTL3、IGF2BP2表达。结果与HepG2细胞相比,在HepG2.2.15细胞中m6A修饰富集,METTL3、IGF2BP2表达水平升高(P<0.05)。与Control组相比,在OE-METTL3组中m6A修饰富集增强,IGF2BP2表达水平升高(P<0.05),HBV复制相关指标(HBV DNA、HBV rcDNA、HBV cccDNA、HBV pgRNA)升高(P<0.01);在si-METTL3组中则相反。生物信息学分析及免疫共沉淀显示METTL3与IGF2BP2为互作蛋白。与Control组相比,在si-IGF2BP2组中m6A修饰富集减弱,METTL3表达水平降低(P<0.01),HBV复制相关指标降低(P<0.01)。在OE-METTL3+si-IGF2BP2组中,HBV复制相关指标较OE-METTL3组降低(P<0.001)。在si-METTL3+si-IGF2BP2组中,HBV复制相关指标较si-METTL3组、si-IGF2BP2组降低(P<0.05)。结论METTL3依赖IGF2BP2富集m6A通过增强HBV rcDNA转化为cccDNA,进而增强pgRNA逆转录复制病毒。

关键词：甲基转移酶样3 胰岛素样生长因子2 mRNA结合蛋白2 N6-甲基腺苷乙型肝炎病毒

融合注意力机制的DeeplabV3+服装图像分割方法

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计算机科学 2024年第S1期51卷 581-587页

作者：肖雅慧张自力胡新荣彭涛张俊武汉纺织大学计算机与人工智能学院武汉430200 湖北省服装信息化工程技术研究中心武汉430200 武汉工程大学计算机科学与工程学院武汉430205

针对在服装图像语义分割中存在由服装颜色、纹理、背景以及多目标遮挡导致的边缘分割粗糙和分割精度低等问题,文中基于Deeplabv3+框架,提出了一种图像语义分割算法(FFDNet)。首先,模型的骨干网络采用ResNet101网络,并添加通道空间注意... 详细信息

针对在服装图像语义分割中存在由服装颜色、纹理、背景以及多目标遮挡导致的边缘分割粗糙和分割精度低等问题,文中基于Deeplabv3+框架,提出了一种图像语义分割算法(FFDNet)。首先,模型的骨干网络采用ResNet101网络,并添加通道空间注意力模块(Feature-Enhanced Attention Module,FEAM),通过对特征图加权来挖掘并增强特征信息,提高网络表达能力。其次引入特征对齐模块(Feature Align Module,FAM)作为一种新的上采样方式,解决不同尺度特征融合之间特征未对齐导致分割错误且效率低的问题,以此提高对服装图像分割的准确性和鲁棒性。最后,FFDNet在Deepfashion2和PASCAL VOC 2012数据集上的平均交并比分别达到55.2%和79.4%;在参数量方面,该模型相比原模型在Deepfashion2上仅增加了0.61 MB。与其他现有经典模型对比,其分割性能更优,能有效捕获图像局部细节信息,减少像素分类错误。

关键词：服装图像语义分割注意力机制 Deeplabv3+网络特征对齐

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激光跟踪仪几何结构误差标定及修正

光学精密工程 2024年第11期32卷 1639-1652页

作者：王珊张滋黎董登峰周维虎纪荣祎潘映伶王国名崔成君中国科学院微电子研究所北京100029 中国科学院大学北京100049

为了提高激光跟踪仪坐标测量精度,分析了跟踪仪的几何结构误差,研究了横竖轴平移误差、横竖轴倾斜误差、激光平移误差和激光倾斜误差的标定和修正方法。利用几何分析法建立了几何结构误差模型,基于投影图像测量仪和检棒、PSD搭建了几何... 详细信息

为了提高激光跟踪仪坐标测量精度,分析了跟踪仪的几何结构误差,研究了横竖轴平移误差、横竖轴倾斜误差、激光平移误差和激光倾斜误差的标定和修正方法。利用几何分析法建立了几何结构误差模型,基于投影图像测量仪和检棒、PSD搭建了几何误差参数的标定装置,实现对几何误差的快速自动高精度标定及补偿。最后,利用误差标定实验测量出的几何误差代入误差补偿模型,与标尺的长度进行比对分析。实验结果表明:经几何误差修正后的跟踪仪坐标测量误差从13μm/m减小到4μm/m以内,测量精度约提升了9μm/m,验证了几何误差标定和修正方法的正确性,该方法可以提高激光跟踪仪的坐标测量精度。

关键词：激光跟踪仪几何结构误差误差标定误差修正最小二乘法

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四川盆地德阳-安岳凹槽形成机理及灯影组沉积新格局

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天然气工业 2024年第8期44卷 13-28页

作者：周刚罗冰张新徐少立张本健马奎梁艺苇严威钟原张自力兰才俊李堃宇中国石油西南油气田公司勘探开发研究院北京源烃泰克科技有限公司

四川盆地德阳—安岳凹槽两侧陡坎带震旦系灯影组天然气勘探不断取得新突破,是盆地内天然气增储上产的重要领域。为了明确该凹槽的形成机理、形成期次及沉积新格局,进一步指导灯影组气藏的深化勘探,采用最新大连片三维地震成果、结合钻... 详细信息

四川盆地德阳—安岳凹槽两侧陡坎带震旦系灯影组天然气勘探不断取得新突破,是盆地内天然气增储上产的重要领域。为了明确该凹槽的形成机理、形成期次及沉积新格局,进一步指导灯影组气藏的深化勘探,采用最新大连片三维地震成果、结合钻井等资料,分析了各期陡坎之间、陡坎与台缘带之间的空间展布关系,探索了陡坎的演化规律,进一步明确了天然气的勘探方向。研究结果表明:①德阳—安岳凹槽陡坎总体表现为侵蚀谷特征,同沉积小断层的作用不明显;②灯影组二段(以下简称灯二段)发育Ⅰ、Ⅱ两个陡坎,灯影组四段(以下简称灯四段)发育一个陡坎,分别在桐湾Ⅰ和Ⅱ、Ⅲ幕侵蚀作用形成,这些陡坎与灯二段、灯四段台缘带无关;③灯二段沉积时期,受控于基底垒堑格局,发育由南向北进积的4~5排台缘带,呈北东向展布,其中蓬莱地区发育两个大型台缘带,台缘带丘滩体被陡坎Ⅱ截断,叠加岩溶作用形成优质储层。结论认为:①高石梯—磨溪地区灯四段与灯二段的陡坎叠合区发育灯四段陡坎型台缘带,而在灯四段槽上带,丘滩体仍呈北东向发育,表明该地区受陡坎Ⅱ与北东向古地貌双重因素控制;②蓬莱地区陡坎Ⅱ坡度变小,对灯四段台缘带控制作用减弱直至消失,主要发育2排北东向展布的缓坡型台缘带,即蓬莱①、②台缘带,蓬莱地区可作为今后天然气勘探重点关注目标区。

关键词：四川盆地德阳—安岳凹槽震旦系灯影组台缘带侵蚀谷阶地沉积