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Versatile chiroptical induction/manipulation through specific solvation of ion pairs by alcohols

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Science China Chemistry 2024年

作者： Chunhong Liu Xin Chen Yanling Shen Ting Zhao Dayang Zhou Kun Li jiecheng Ji Wanhua Wu Xuemei Pu Cheng Yang Key Laboratory of Green Chemistry & Technology of Ministry of Education Sichuan University Comprehensive Analysis Center ISIR Osaka University

While extensive research has explored manipulating supramolecular chirality through internal and external factors, the specific solvation effect remains uncharted territory. This study synthesized ortho-functionalized pillar[5]arene（P[5]） derivatives Mn and Dn via thiol-Michael addition, characterizing them through spectroscopic and X-ray single-crystal analyses. Mn and Dn interacted with chiral amines, yielding significant circular dichroism（CD） responses. Intriguingly, the chiral induction exhibited pronounced specific solvation effects, where achiral alcohols either enhanced, attenuated, or reversed CD signals. Testing over40 alcohols revealed correlations between the specific solvation effects and alcohol polarity and acidity. Molecular dynamics simulations unveiled that the alcohol interacted distinctly through hydrogen bonding, with one ion pair bonding up to four alcohol molecules. The Rp-and Sp-preference of the P[5] core could be altered by the number of bonded alcohols. This work uncovers the critical role of alcohol-specific solvation in ion pair-involved chiral assembly, pertinent for asymmetric ion-pairing catalysis and the use of alcohol additives in organic solvents.

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可溶性鸟苷酸环化酶激动剂维利西呱在心力衰竭治疗中的研究进展

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临床心血管病杂志 2024年第2期40卷 96-100页

作者：赵烊烊彭杰成安徽医科大学附属安庆第一人民医院心内科安徽安庆246003 安徽医科大学第五临床医学院

心力衰竭(heart failure,HF)是心血管疾病发展的终末结局和心血管疾病患者最主要的死亡原因。近年来,随着进一步的研究,HF的治疗正在不断完善,然而HF患者的高住院率和高病死率在目前依旧是一大难题,其生活质量和预后仍处于较低水平。而... 详细信息

心力衰竭(heart failure,HF)是心血管疾病发展的终末结局和心血管疾病患者最主要的死亡原因。近年来,随着进一步的研究,HF的治疗正在不断完善,然而HF患者的高住院率和高病死率在目前依旧是一大难题,其生活质量和预后仍处于较低水平。而维利西呱作为一种可溶性鸟苷酸环化酶激动剂,以其独特的作用机制和良好的安全性、耐受性为HF治疗提供了新思路,可谓潜力巨大。本文就维利西呱的作用通路、安全性、耐受性方面以及目前相关临床研究进展进行综述。

关键词：维利西呱心力衰竭可溶性鸟苷酸环化酶激动剂一氧化氮-可溶性鸟苷酸环化酶-环磷酸鸟苷信号途径

Model-driven CT reconstruction algorithm for nano-resolution x-ray phase contrast imaging

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Chinese Physics B 2024年第7期33卷 646-650页

作者：谭雨航蔡学宝杨杰成苏婷郑海荣梁栋朱佩平葛永帅 Research Center for Medical Artificial Intelligence Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Institute of Electronic Paper Displays South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China Paul C Lauterbur Research Center for Biomedical Imaging Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

The low-density imaging performance of a zone plate-based nano-resolution hard x-ray computed tomography(CT)system can be significantly improved by incorporating a grating-based Lau interferometer. Due to the diffraction, however,the acquired nano-resolution phase signal may suffer splitting problem, which impedes the direct reconstruction of phase contrast CT(nPCT) images. To overcome, a new model-driven nPCT image reconstruction algorithm is developed in this study. In it, the diffraction procedure is mathematically modeled into a matrix B, from which the projections without signal splitting can be generated invertedly. Furthermore, a penalized weighted least-square model with total variation(PWLSTV) is employed to denoise these projections, from which nPCT images with high accuracy are directly *** experiments demonstrate that this new algorithm is able to work with phase projections having any splitting distances. Moreover, results also reveal that nPCT images of higher signal-to-noise-ratio(SNR) could be reconstructed from projections having larger splitting distances. In summary, a novel model-driven nPCT image reconstruction algorithm with high accuracy and robustness is verified for the Lau interferometer-based hard x-ray nano-resolution phase contrast imaging.

关键词： splitting phase image reconstruction algorithm grating interferometer

CMOS图像传感器质子位移损伤效应实验与分析

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光学学报 2024年第13期44卷 297-305页

作者：杨洁铖殷倩郭刚张艳文李理钟向丽湘潭大学材料科学与工程学院湖南湘潭411105 中国原子能科学研究院国家原子能机构抗辐照应用技术创新中心北京102413

为了分析不同能量质子辐射引发的位移损伤对CMOS图像传感器(CIS)参数影响的差异,以商用CIS为研究对象,在中国原子能科学研究院回旋加速器上开展了50 MeV和90 MeV质子辐照实验,分析了不同能量及注量的质子辐照下器件的暗信号、热像素和... 详细信息

为了分析不同能量质子辐射引发的位移损伤对CMOS图像传感器(CIS)参数影响的差异,以商用CIS为研究对象,在中国原子能科学研究院回旋加速器上开展了50 MeV和90 MeV质子辐照实验,分析了不同能量及注量的质子辐照下器件的暗信号、热像素和随机电码信号(RTS)等参数的退化规律。实验结果表明:平均暗信号的增加可以用位移损伤剂量等效,而相同位移损伤剂量下50 MeV质子辐照后表现出更大的暗信号非均匀性(DSNU)和热像素。像素间RTS现象是质子辐照后不同类型的缺陷所导致的。计算机辅助设计技术(TCAD)模拟结果表明深能级的点缺陷导致载流子浓度更高的热产生率,且团簇缺陷产生率高于简单点缺陷,产生率的不同导致像素间暗信号产生差异,进而产生DSNU和RTS现象。

关键词： CMOS图像传感器质子暗信号随机电码信号缺陷

Study of Disconnectable Riser Turret Mooring System Applied in the South China Sea

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China Ocean Engineering 1991年第3期6卷 269-278页

作者： Chen, jiecheng Guangzhou Marine Engineering Corp Guangzhou China

The present research has been made on the Disconnectable Riser Turret Mooring (DRTM) System which could be used in the oil fields of the South China Sea. The selection of the principal dimensions and their effect on the characteristics of the system have been discussed. By means of a computer program, the synthetical appraisement has been made in the ultimate mooring condition, disconnecting condition and reconnecting condition respectively. Mean-while, a comparison has been made between DRTM system and CALM system. It has been indicated that DRTM is suitable for the South China Sea and has technological and economical preponderance.

关键词： Marine Risers Design Single Point Mooring

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一种双工质气体压缩储能系统及其可行性分析

南方能源建设 2024年第2期11卷 154-161页

作者：郑开云池捷成张学锋势加透博(上海)能源科技有限公司上海201815

[目的]压缩空气储能系统储气库容大、储气压力高,往往需要采用地下盐穴储气库,项目开发受制于盐穴资源的稀缺性。压缩二氧化碳储能系统采用常压柔性气膜储气仓储存二氧化碳气体,气膜仓体积巨大,占地面积过大,难以满足建设用地指标有要... 详细信息

[目的]压缩空气储能系统储气库容大、储气压力高,往往需要采用地下盐穴储气库,项目开发受制于盐穴资源的稀缺性。压缩二氧化碳储能系统采用常压柔性气膜储气仓储存二氧化碳气体,气膜仓体积巨大,占地面积过大,难以满足建设用地指标有要求的工业园区。为了实现气体压缩储能在工业园区的广泛应用,提出了一种双工质气体压缩储能系统。[方法]系统整合压缩空气储能与压缩二氧化碳储能两个系统,并共用储气库。储气库采用特殊设计的承压容器,由柔性隔膜分隔成等压且可缩放的空气腔和二氧化碳气腔。系统通过压缩空气回路和压缩二氧化碳回路的协同工作实现储能和释能,并保持储气库维持恒压运行。为了评估系统的储能效果及能量密度,对基于3 MPa储气压力地面储气库方式的100 MW/400 MWh储能系统进行初步的热力学计算,并对工程可行性进行分析。[结果]结果表明:系统的储能效率为70.20%;能量密度为3.85 kWh/m^(3)。系统适合工业园区配套储能,并可发挥其电、气、冷、热多联供的功能,相比电化学储能,具有显著的商业竞争力优势。[结论]针对工业园区储能场景,双工质气体压缩储能选址灵活、技术可行、设备成熟、成本可控,具有重大的潜在商业价值。

关键词：压缩空气储能压缩二氧化碳储能能量密度储能效率多联供

Stability of nonlinear Schrodinger equations on modulation spaces

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Frontiers of Mathematics in China 2014年第2期9卷 275-301页

作者： Weichao GUO jiecheng CHEN Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Mathematicsl Zhejiang Normal University Jinhua 321004 China

We consider the Cauchy problem for a family of SchrSdinger equations with initial data in modulation spaces Mp,1^s. We develop the existence, uniqueness, blowup criterion, stability of regularity, scattering theory, a... 详细信息

关键词： Schrodinger equation blow-up rate scattering stability theory stability of regularity modulation space

BOUNDEDNESS OF MAXIMAL SINGULAR INTEGRALS

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Chinese Annals of Mathematics,Series B 2005年第4期26卷 559-568页

作者： CHEN jiecheng ZHU XIANGRONG Department of Mathematics Zhejiang University （Xixi Campus） Hangzhou 310028 China

The authors study the singular integrals under the Hormander condition and the measure not satisfying the doubling condition. At first, if the corresponding singular integral is bounded from L^2 to itself, it is proved that the maximal singular integral is bounded from L^∞ to RBMO except that it is infinite μ-a.e. on R^d. A sufficient condition and a necessary condition such that the maximal singular integral is bounded from L^2 to itself are also obtained. There is a small gap between the two conditions.

关键词： Maximal singular integral RBMO

肌肉电阻抗技术应用于神经肌肉疾病评估和机制研究进展

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生物医学工程研究 2024年第1期43卷 16-23页

作者：郭杰承王翔李乐西北工业大学医学研究院西安710072

神经肌肉疾病涉及周围神经和肌肉的损伤或功能障碍,严重影响受影响个体的生活质量。在大多数情况下,常用的功能影像临床评估工具如磁共振成像(magnetic resonance imaging,MRI)、计算机断层扫描(computed tomography,CT)、双能X线吸收仪... 详细信息

神经肌肉疾病涉及周围神经和肌肉的损伤或功能障碍,严重影响受影响个体的生活质量。在大多数情况下,常用的功能影像临床评估工具如磁共振成像(magnetic resonance imaging,MRI)、计算机断层扫描(computed tomography,CT)、双能X线吸收仪(dualenergy X-ray absorptiometry,DXA)和超声成像(ultrasonography),可以诊断疾病、评估治疗效果。肌肉电阻抗(electrical impedance myography,EIM)相对于其他评估技术具有简便性、定量性、灵活性、可重复性、对退化肌肉敏感等优势,被广泛应用于临床评估中。本综述将针对EIM应用于神经肌肉疾病的研究进行简单总结。

关键词：神经肌肉疾病肌肉电阻抗临床评估诊断康复