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中国医学伦理学 2023年第10期36卷 1085-1089页

作者：李晨阳石旭雯天津医科大学医学人文学院天津300041

21世纪以来,随着生物医学的蓬勃发展,人兽嵌合体技术的研究和讨论引起了广泛关注。人兽嵌合体的一般研究是将人类干细胞导入去除器官基因的动物胚胎,旨在人兽嵌合体内培育出人类器官,以解决人体器官的供体短缺问题和为相关科研的发展提... 详细信息

21世纪以来,随着生物医学的蓬勃发展,人兽嵌合体技术的研究和讨论引起了广泛关注。人兽嵌合体的一般研究是将人类干细胞导入去除器官基因的动物胚胎,旨在人兽嵌合体内培育出人类器官,以解决人体器官的供体短缺问题和为相关科研的发展提供实验材料等。但因其技术涉及跨物种的基因改造,破坏了物种界限和生态位的自然性,引起了威胁物种安全、损害人类尊严等多方面的伦理问题。人兽嵌合体技术的发展是科技进步的时代选择,存在其必然性和合理性,不应该受到绝对程度的禁止,但必须遵守安全且有利、尊重、公正等伦理学原则,在严格有序的伦理规范下和谐运行。

关键词：人兽嵌合体物种界限人类尊严伦理规范伦理问题

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Parameters Optimization Method for ADRC of Permanent Magnet Synchronous Motor Based on CMA-ES

Parameters Optimization Method for ADRC of Permanent Magnet ...

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第43届中国控制会议

作者： Tianjian Jiang Yang Yang Zhiyuan li Tianqi Yang xuwen Chen College of Automation and College of Aritifical Intelligence Nanjing University of Posts and Telecommunications College of Internet of Things Nanjing University of Posts and Telecommunications

ISBN: (数字)9789887581581

ISBN: (纸本)9798350366907

Active disturbance rejection control(ADRC) is widely used to control permanent magnet synchronous motors(PMSM). However, the settings of gain parameters in ADRC is often dependent on engineers' experience. Also, it is difficult to design the parameters accurately by hand to achieve satisfactory results. A method based on evolution strategy with covariance matrix adaptation(CMA-ES) for optimizing the gain parameters of ADRC is proposed. By setting up some optimization tasks and using the CMA-ES algorithm, reinforcement learning is performed on the parameters of ADRC. In view of the high population size and complexity of CMA-ES, we adopt a parallel computation method to speed up the optimization *** method can effectively optimize the ADRC gain parameters to adapt to the specified application environment, and at the same time reduce the dependence of setting ADRC parameters on human experience as well as time consumption. Finally, we verify that this CMA-ES-based parameter optimization method can effectively improve the control performance of the motor by running simulations and comparing the motor speed changes before and after optimization.

关键词： Permanent-magnet Synchronous Motor Active Disturbance Rejection Control Field-oriented Control Swarm Optimization High Throughput Computing Modern Control

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Elucidating Orbital Delocalization Effects on Boosting Electrochemiluminescence Efficiency of Carbon Nitrides

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ADVANCED OPTICAL MATERIALS 2022年第18期10卷

作者： Fang, Yanfeng Hou, Yuhua Yang, Hong Chen, Ran li, Wang Ma, Jin Han, Dan Cao, xuwen liu, Songqin Shen, Yanfei Zhang, Yuanjian Southeast Univ Jiangsu Engn Lab Smart Carbon Rich Mat & Device Jiangsu Prov Hitech Key Lab Biomed Res State Key Lab BioelectSch Chem & Chem Engn Nanjing 211189 Peoples R China Southeast Univ Med Sch Nanjing 211189 Peoples R China

Highly efficient inter-conversion of different types of energy is the core of science and technology. Among them, electrochemiluminescence (ECL), an emission of light excited by electrochemical reactions, has drawn attention as a powerful tool across diverse fields in addressing global energy, environment, and health challenges. Nonetheless, the ECL efficiency (phi(ECL)) of most luminophores in aqueous solutions is low, significantly hampering their broad applications. Along this line, developing ECL luminophores with high phi(ECL) and understanding the associated intrinsic factors is highly envisioned. Herein, taking carbon nitride (CN) with rigid 2D backbones as an emerging model luminophore, it is reported that the orbital delocalization is a unified and quantifiable factor for its phi(ECL). Behind the complicated transformation of molecular structures of cyano-terminal groups and triazine/heptazine basal frameworks, the orbital delocalization of CN is found to be generally improved at an elevated condensation temperature. Such intrinsic evolution in electronic structure favored the electron injection in excitation and follow-up photon emission in ECL for CN. As a result, the cathodic phi(ECL) of CN is remarkably improved to a new milestone of 24-fold greater than the previous record.

关键词： carbon nitrides electrochemiluminescence energy conversion efficiency orbital delocalization photoelectrochemistry

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Enhancing gas production and CO2 sequestration from marine hydrate reservoirs through optimized CO2 hydrate cap

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ENERGY 2024年 303卷

作者： Guo, Yang li, Shuxia Sun, Hao Wu, Didi liu, Lu Zhang, Ningtao Qin, xuwen Lu, Cheng China Univ Petr East China State Key Lab Deep Oil & Gas Qingdao 266580 Peoples R China China Univ Petr East China Sch Petr Engn Qingdao 266580 Peoples R China East China Bur Sinopec Explorat & Dev Res Inst Nanjing 210019 Peoples R China China Geol Survey China Aero Geophys Survey & Remote Sensing Ctr Nat Beijing 100083 Peoples R China China Geol Survey Minist Nat Resources Oil & Gas Resources Survey Beijing 100083 Peoples R China

The invasion of formation water during marine hydrate production gravely affects gas productivity. CO2 hydrate caps effectively inhibit water invasion while sequestering CO2, which is considered an excellent prospective application. However, forming field -scale artificial CO2 hydrate caps remains a global challenge. This study proposed an innovative method for forming an artificial CO2 hydrate cap. The fracture length, injection time, production pressure, and production well distance, which are all factors that affect sealing capacity and production enhancement, were optimized. Results indicated that the sealing capacity exhibited a trend of initially increasing and subsequently decreasing with fracture length. The injection time was positively correlated with the sealing capacity and was sufficient to seal both vertically and horizontally once it reached 4 years. In addition to sequestering CO2, the CO2 hydrate cap enhanced gas production by 146.56 % and reduced water production by 37.47 % compared to direct depressurization. CO2 invasion occurred when the well spacing was too close, while being distant was not favorable for pressure propagation and heat utilization by the CO2 hydrate cap. This method simultaneously achieves multiple goals for energy and environmental, providing essential implications for the future commercial application of marine hydrates.

关键词： Gas hydrate CO2 hydrate cap Enhanced gas production CO2 sequestration Numerical simulation

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Carbon Sequestration in Overlying Methane Hydrate Layers Via Hydrate Technology: Feasibility and Synergistic Benefits

SSRN

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SSRN 2024年

作者： Zhang, Zhaobin li, Yuxuan li, Shouding He, Jianming Xie, Zhuoran li, Xiao Lu, Cheng Qin, xuwen Key Laboratory of Shale Gas and Geoengineering Institute of Geology and Geophysics Chinese Academy of Sciences Beijing100029 China Innovation Academy for Earth Science Chinese Academy of Sciences Beijing100029 China College of Earth and Planetary Sciences University of Chinese Academy of Sciences Beijing100049 China Oil and Gas Resources Survey China Geological Survey Ministry of Natural Resources Beijing100083 China China Geological Survey Ministry of Natural Resources Beijing100037 China

Excessive carbon dioxide emissions pose a global environmental issue, and carbon sequestration technology offers a solution. This study proposes a novel approach for carbon dioxide sequestration in the overlying layers of methane hydrate reservoirs using carbon dioxide hydrate technology. The feasibility and risks of this method are evaluated over a time scale of 100,000 years. The research indicates that after injection into the overlying layers of methane hydrate reservoirs, carbon dioxide migrates upwards driven by buoyancy, gradually forming highly saturated carbon dioxide hydrate shells at the leading edge of migration. Within these carbon dioxide hydrate shells, a portion of the carbon dioxide is sequestered in liquid and dissolved forms;however, over tens of thousands of years, some carbon dioxide escapes via dissolution and diffusion. The study further discusses the synergistic effects between methane hydrate extraction and carbon sequestration in overlying layers, showing that the cold seawater downdraw effect induced by methane hydrate extraction significantly enhances the efficiency and safety of carbon dioxide hydrate sequestration in the overlying layers. Given the widespread distribution of methane hydrate reservoirs globally, this research provides new insights into carbon sequestration technology. © 2024, The Authors. All rights reserved.

关键词： Carbon dioxide

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Direct Arylation Polycondensation-Derived Polythiophene Achieves Over 16% Efficiency in Binary Organic Solar Cells via Tuning Aggregation and Miscibility

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ADVANCED ENERGY MATERIALS 2024年第47期14卷

作者： Zhang, xuwen Zhang, Tao liang, Ziqi Shi, Yibo li, Saimeng Xu, Chenhui li, Miaomiao Ye, Long Hou, Jianhui Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin Key Lab Mol Optoelect SciKey Lab Organ In Minist EducCollaborat Innovat Ctr Chem Sci & Engn Tianjin 300350 Peoples R China Chinese Acad Sci Inst Chem CAS Res Educ Ctr Excellence Mol Sci State Key Lab Polymer Phys & ChemBeijing Natl Lab Beijing 100190 Peoples R China

Polythiophenes are the most appealing donor materials in organic solar cells (OSCs) due to their simple chemical structures. However, the top-performance polythiophenes are typically synthesized via Stille polycondensation, which is problematic due to significant toxicity and poor atom economy. By contrast, direct arylation polycondensation (DArP) is an eco-friendly, and atom-efficient alternative for synthesizing conjugated polymers, while the best efficiency for DArP-derived polythiophenes is below 12%. This study reports a series of polythiophene-based donors synthesized via DArP. Among these, PT4F-Th reaches a power conversion efficiency (PCE) of 16.4%, which not only matches the current record for polythiophene-based donor materials, but also marks the highest PCE achieved by DArP-derived donors to date. The superior performance of PT4F-Th is largely attributed to its optimal temperature-dependent aggregation behavior and moderate miscibility with acceptors, along with the highest crystallinity among the candidates, resulting in the most favorable blend film morphology. This study underscores the significant potential of DArP-derived polythiophenes in developing high-performance and eco-friendly OSCs. A series of polythiophene-based donors are synthesized using direct arylation polycondensation (DArP), highlighting PT4F-Th, which achieves an outstanding power conversion efficiency (PCE) of 16.4% in binary organic solar cells (OSCs). This efficiency sets a new record for DArP-derived donors. Blend film morphology is characterized by X-ray scattering and microscopy, emphasizing the synergistic effects of temperature-dependent aggregation behavior and miscibility. image

关键词： direct arylation polycondensation miscibility organic solar cells polythiophene power conversion efficiency

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藏东南输电走廊北线区域地质环境与主要地质安全问题

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地质力学学报 2025年第1期31卷 91-108页

作者：田旭文王彦兵朱姝姚鑫李显鑫中国地质科学院地质力学研究所北京100081 国网经济技术研究院有限公司北京102209 自然资源部活动构造与地质安全重点实验室北京100081

藏东南地区独特的地形地貌和气候条件特点,使之蕴藏着非常丰富的水电资源。为保障藏东南输电走廊北线的地质选线、建设和运营工作,文章通过归纳总结国内外文献资料,详细阐述了输电走廊北线沿线区域地质环境和主要地质安全隐患,并对藏东... 详细信息

藏东南地区独特的地形地貌和气候条件特点,使之蕴藏着非常丰富的水电资源。为保障藏东南输电走廊北线的地质选线、建设和运营工作,文章通过归纳总结国内外文献资料,详细阐述了输电走廊北线沿线区域地质环境和主要地质安全隐患,并对藏东南输电走廊进一步灾害识别与监测工作提出了合理建议。结果表明:藏东南输电走廊沿线构造活动强烈、活动断裂发育、强震频发、地形地貌差异显著、岩土体结构损伤和劣化等独特的区域地质环境,极易诱发地质安全隐患;藏东南输电走廊北线的地质安全隐患主要包括滑坡、崩塌、泥石流、雪(冰)崩、冰湖溃决和冻胀融沉等;沿线地质安全隐患的发育受控于极高陡的地形和复杂的地貌条件、升温融雪气候变化、强烈的断裂活动与频发的地震、内外动力耦合诱发的高位远程灾害链等因素;深入融合InSAR技术、光学遥感、无人机摄影测量、机载liDAR技术和在线实地监测等软防控手段的优势,可以有效打破藏东南输电走廊沿线灾害隐患错判、漏判、少判、智能化程度低和精准性差等困局。研究结果将为藏东南地区水电开发项目规划建设中的地质安全风险防控工作提供理论依据,也对藏东南地区可持续发展具有重要的现实意义。

关键词：输电走廊藏东南地区地质安全问题地质灾害工程地质遥感技术

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Effect of multiple-frequency ultrasound-assisted transglutaminase dual modification on the structural, functional characteristics and application of Qingke protein

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ULTRASONICS SONOCHEMISTRY 2023年 94卷 106317页

作者： li, Aijun Guo, Zehang Wang, Zhirong Yang, Qingqing Wen, Leyan Xiang, xuwen Kan, Jianquan Southwest Univ Coll Food Sci 2 Tiansheng Rd Chongqing 400715 Peoples R China Yangzhou Univ Coll Food Sci & Engn Yangzhou 225127 Jiangsu Peoples R China Chinese Hungarian Cooperat Res Ctr Food Sci Chongqing 400715 Peoples R China Minist Agr & Rural Affairs Peoples Republ China Lab Qual & Safety Risk Assessment Agriprod Storage Chongqing 400715 Peoples R China Chongqing Key Lab Special Food Co Built Sichuan & Chongqing 400715 Peoples R China 2 Tiansheng Rd Chongqing 400715 Peoples R China

Qingke protein rich in restricted amino acids such as lysine, while the uncoordination of ratio of glutenin and gliadin in Qingke protein has a negative impact on its processing properties. In this study, the effect of multiple-frequency ultrasound combined with transglutaminase treatment on the functional and structural properties of Qingke protein and its application in noodle manufacture were investigated. The results showed that compared with the control, ultrasound-assisted transglutaminase dual modification significantly increased the water and oil holding capacity, apparent viscosity, foaming ability, and emulsifying activity index of Qingke protein, which exhibited a higher storage modulus G' (P < 0.05). Meanwhile, ultrasound combined with transglutaminase treatment enhanced the cross-linking degree of Qingke protein (P < 0.05), as shown by decreased free amino group and free sulfhydryl group contents, and increased disulfide bond content. Moreover, after the ultrasound-assisted transglutaminase dual modification treatment, the fluorescence intensity, the contents of alpha-helix and random coil in the secondary structure of Qingke protein significantly decreased, while the beta-sheet content increased (P < 0.05) compared with control. SDS-PAGE results showed that the bands of Qingke protein treated by ultrasound combined with transglutaminase became unclear. Furthermore, the quality of Qingke noodles made with Qingke powder (140 g/kg dual modified Qingke protein mixed with 860 g/kg extracted Qingke starch) and wheat gluten 60-70 g/kg was similar to that of wheat noodles. In summary, multiple-frequency ultrasound combined with transglutaminase dual modification can significantly improve the physicochemical properties of Qingke protein and the modified Qingke proteins can be used as novel ingredients for Qingke noodles.

关键词： Qingke protein Modification Functional properties Application Qingke noodles

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Enhanced gas production from low-permeability hydrate reservoirs based on embedded discrete fracture models: Influence of branch parameters

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ENERGY 2023年第1期282卷

作者： Guo, Yang li, Shuxia Qin, xuwen Lu, Cheng Wu, Didi liu, Lu Zhang, Ningtao China Univ Petr East China Key Lab Unconvent Oil & Gas Dev Minist Educ Qingdao 266580 Peoples R China China Univ Petr East China Sch Petr Engn Qingdao 266580 Peoples R China Minist Nat Resources China Geol Survey Beijing 100037 Peoples R China Minist Nat Resources China Geol Survey Oil & Gas Resources Survey Beijing 100083 Peoples R China East China Bur Sinopec Explorat & Dev Res Inst Nanjing 210019 Peoples R China

The low permeability of marine hydrate reservoirs makes it difficult for trail results to meet the demand for exploitation. Hydraulic fracturing and multi-branch wells are the primary methods for enhancing productivity. This study proposed a new production enhancement method of multi-branch wells combined with multi-stage fracturing (MWMF) based on the embedded discrete fracture model (EDFM). By simulation of the Shenhu area, the multi-physical field evolution of the MWMF production process was first revealed, followed by the systematic analysis of the MWMF production enhancement effect with branch parameters. Results indicated that the cumulative gas production of MWMF increased by 327% compared with only horizontal wells. The production of four-branch wells exhibited a 7% reduction compared to horizontal wells using the MWMF method, suggesting increased branch numbers inhibit production. Increasing branch length was positively correlated with enhanced production. Notably, the influence of branch length on gas production became more pronounced as the number of branches increased. The interface of the three-phase layer (TPL) and hydrate-bearing layer (HBL) was the most suitable location for branch well placement. This novel study provides valuable insights into new applications of the MWMF method in developing low-permeability hydrate reservoirs.

关键词： Natural gas hydrate Multi-branch well Multi-stage fracture Embedded discrete fracture model Enhanced gas production

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心电信号的QRS波检测算法的研究

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兵器装备工程学报 2018年第9期39卷 171-175页

作者：李明星李旭雯魏鑫中国航天科工运载技术研究院北京分院北京102308 北京工业大学生命科学与生物工程学院北京100124 北京控制与电子技术研究所北京100038

对QRS波群快速、准确定位是心电信号自动检测和分析的关键,其前提条件是消除心电信号中的各种噪声干扰;针对提高QRS波群检测算法的抗噪性能,提出了一种基于经验模态分解方法和平稳小波变换相结合的QRS波检测方法;该方法对QRS波检测准确... 详细信息

对QRS波群快速、准确定位是心电信号自动检测和分析的关键,其前提条件是消除心电信号中的各种噪声干扰;针对提高QRS波群检测算法的抗噪性能,提出了一种基于经验模态分解方法和平稳小波变换相结合的QRS波检测方法;该方法对QRS波检测准确率高、定位精度好。

关键词： QRS波群经验模态分解小波变换模极大值

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