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Primary and Secondary Calcite in Chinese Loess Distinguished by Crystallinity and Implications for Illuviation Depth and East Asian Summer Monsoon Intensity

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Journal of Earth Science 2024年

作者： Yan zhao Kangjun Huang Yuanqiang Guo Pan Zhang Yawen Lu Long Ma State Key Laboratory of Continental Dynamics， Shaanxi Key Laboratory of Early Life and Environment， Department of Geology， Northwest University

The crystallinity has the potential to distinguish the primary and secondary calcite in Chinese loess， which then provides insights into illuviation depth and variations of the East Asian summer monsoon. However， this aspect has been rarely investigated. In this study， we defined the crystallinity of calcite as the Height/Area (H/A) ratio of the diffracted peak at crystal face (1 0 4). The H/A ratio inversely correlates with the average width of the diffracted peak， where a higher H/A ratio indicates higher crystallinity of calcite. Through the mixing and synthetic experiments， we found that the H/A ratio is minimally affected by factors such as calcite content， deposition temperature or rate but significantly influenced by the ionic impurity and the mixing proportion of different calcites. Subsequently， we examined desert samples of loess sources and loess carbonate nodules. Desert samples predominantly consist of primary calcite which inherits characteristics from cryptocrystalline limestone with high levels of ionic impurities resulting in low H/A ratio of 4.30 ± 0.51. In contrast， loess carbonate nodules contain abundant secondary calcite precipitated within soil interstices with low levels of ionic impurities leading to a significantly higher H/A ratio of 7.76 ± 0.82. Consequently， higher H/A ratios during interglacial periods compared to glacial periods are attributed to variations in relative proportions between primary and secondary calcite in loess sequences. The thickness， between the glacial-interglacial boundary and the depth where the H/A ratio starts to increase from the bottom to the top in the loess layer， can be used to indicate the illuviation depth of upper-soil carbonates and the intensity of the East Asian summer monsoon. This proxy can be further applied in long-term loess sequences to uncover the summer monsoon evolution.

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简单退火和多重热处理对激光熔覆成形Ti-5321合金断裂韧性的影响

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稀有金属材料与工程 2024年第4期53卷 970-977页

作者：刘国政赵永庆贾蔚菊张艳宋硕毛成亮周伟东北大学辽宁沈阳110819 西北有色金属研究院陕西西安710016

为满足航空航天领域对快速制备高强韧复杂钛合金零件的需求,采用激光熔覆成形新型高强韧Ti-5321(Ti-5Al-3Mo-3V-2Zr-2Cr-1Nb-1Fe)合金,具有成形快、效率高、成形构件性能良好等优势。通过对Ti-5321合金进行简单退火和多重热处理(β相区... 详细信息

为满足航空航天领域对快速制备高强韧复杂钛合金零件的需求,采用激光熔覆成形新型高强韧Ti-5321(Ti-5Al-3Mo-3V-2Zr-2Cr-1Nb-1Fe)合金,具有成形快、效率高、成形构件性能良好等优势。通过对Ti-5321合金进行简单退火和多重热处理(β相区固熔缓冷加时效,BASCA),揭示了其显微组织的演变规律,并探究不同组织对断裂韧性的影响。结果表明:简单退火后,合金呈细长针片状α交织成的网篮组织,其抗拉伸强度为1102 MPa,断裂韧性为68.1 MPa·m^(1/2)。经BASCA热处理后,细长针片状α相全部转变为粗大的片层α相和超细针状α相,且合金的抗拉伸强度提高至1309 MPa,而断裂韧性降低至45.5 MPa·m^(1/2)。BASCA热处理能够提高合金强度,但会降低合金韧性。这是由于网篮组织中细长的针片状α相能够大大增加裂纹扩展阻力,增大裂纹扩展路径曲折程度,从而提高合金的韧性。而BASCA热处理组织中大片层α相具有一定的方向性,裂纹只有在穿过不同β晶粒的大片层α相时才会发生偏转;且裂纹扩展主要发生在超细针状α相中,而超细针状α相尺寸过于细小,不能阻碍裂纹的发展或使裂纹偏转,因此经BASCA热处理后合金的韧性变差。

关键词：激光熔覆成形 Ti-5321合金多重热处理断裂韧性

Optimal operation of Internet Data Center with PV and energy storage type of UPS clusters

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Global Energy Interconnection 2024年第1期7卷 61-70页

作者： Man Chen Yuxin zhao Yuxuan Li Peng Peng Xisheng Tang CSG PGC Energy Storage Research Institute Guangzhou 510000P.R.China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

With the development of green data centers,a large number of Uninterruptible Power Supply(UPS)resources in Internet Data Center(IDC)are becoming idle assets owing to their low utilization *** revitalization of these idle UPS resources is an urgent problem that must be *** on the energy storage type of the UPS(EUPS)and using renewable sources,a solution for IDCs is proposed in this ***,an EUPS cluster classification method based on the concept of shared mechanism niche(CSMN)was proposed to effectively solve the EUPS control ***,the classified EUPS aggregation unit was used to determine the optimal operation of the *** IDC cost minimization optimization model was established,and the Quantum Particle Swarm Optimization(QPSO)algorithm was ***,the economy and effectiveness of the three-tier optimization framework and model were verified through three case studies.

关键词： Three-tier optimization framework Energy storage type of the UPS EUPS cluster classification method Quantum Particle Swarm Optimization

纳米氧化锌对钙钛矿薄膜本征性能和光谱性能的影响研究

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光谱学与光谱分析 2024年第5期44卷 1482-1486页

作者：于嫚谢国鑫赵肖娟李兆西安航空学院材料工程学院陕西西安710077

有机-无机杂化钙钛矿太阳能电池因其优异的光电特性、低廉的制备成本、高效的转换效率等优越特性,成为光伏领域的研究热点。电子传输层作为钙钛矿电池的核心层,主要起到提取和传输光生载流子的作用,且能够作为空穴阻挡层,抑制钙钛矿活... 详细信息

有机-无机杂化钙钛矿太阳能电池因其优异的光电特性、低廉的制备成本、高效的转换效率等优越特性,成为光伏领域的研究热点。电子传输层作为钙钛矿电池的核心层,主要起到提取和传输光生载流子的作用,且能够作为空穴阻挡层,抑制钙钛矿活性层中电荷复合,所以优异性能的电子传输层对钙钛矿太阳能电池的发展至关重要。可目前钙钛矿光伏器件常用的刚性电子传输层(介孔层或致密层)均需要高温烧结,这限制了其在柔性钙钛矿器件方面的应用。因此,开发一种可应用于钙钛矿光伏领域的柔性电子传输层成为当前亟待解决的问题之一。纳米ZnO具有合适的能级和较高的电子迁移率,且可以通过低温制备,被广泛应用在光伏器件中作为电子传输层。因此,通过旋涂法和静电纺丝法分别制备了刚性纳米ZnO和柔性纳米ZnO电子传输层,确定了静电纺丝法制备柔性纳米ZnO的最佳制备工艺。利用扫描电子显微镜、X射线衍射仪、紫外可见分光光度计和稳态/瞬态荧光光谱系统研究了刚性和柔性纳米ZnO对钙钛矿薄膜形貌、结构和光谱性能的影响。结果表明,钙钛矿薄膜的形貌对基底纳米ZnO的形貌依赖性很强。而基于刚性和柔性纳米ZnO的钙钛矿薄膜几乎呈现相同的结构和光谱吸收范围,荧光发射峰均在770 nm附近,且柔性纳米ZnO的荧光猝灭效率为82%,几乎和刚性纳米ZnO的荧光猝灭效率(85%)相媲美。进一步,根据瞬态荧光动力学数据计算获得刚性和柔性纳米ZnO的界面电荷分离效率分别为61%和41%,这表明通过静电纺丝法制备的柔性纳米ZnO具备一定的界面电荷分离能力,有望成为新型的柔性电子传输层。这对柔性基底钙钛矿太阳能电池的设计具有重要参考价值,对促进钙钛矿光伏应用具有现实意义。

关键词：纳米氧化锌钙钛矿薄膜形貌结构光谱性能

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Green Gold

The World of Chinese 2024年第3期 12-19页

作者： Li Wei Hayley zhao Jiayu Zhang 不详

Photographer Li Wei, better known as Dameng, captures how avocado farming transformed ethnic communities in a small southwestern village Three years ago, when Li Wei returned to his hometown, Menglian, he was pleasantly surprised by avocado trees blanketing the surrounding *** Myanmar, Menglian is an autonomous region for the Dai, Lahu, and Va ethnic groups that once relied primarily on tea planting and tourism. Now, it makes up nearly 80percent of China’s domestic avocado ***, which means “a great place to find” in the Dai dialect, offers an ideal climate for avocado farming—a relatively new industry in China—with its warm temperatures and abundant rainfall.

关键词： mountains autonomous transformed

Epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China:a hospital-based retrospective study

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Neural Regeneration Research 2024年第5期19卷 1126-1132页

作者： Hengxing Zhou Yongfu Lou Lingxiao Chen Yi Kang Lu Liu Zhiwei Cai David BAnderson Wei Wang Chi Zhang Jinghua Wang Guangzhi Ning Yanzheng Gao Baorong He Wenyuan Ding Yisheng Wang Wei Mei Yueming song Yue Zhou Maosheng Xia Huan Wang Jie zhao Guoyong Yin Tao Zhang Feng Jing Rusen Zhu Bin Meng Li Duan Zhongmin Zhang Desheng Wu Zhengdong Cai Lin Huang Zhanhai Yin Kainan Li Shibao Lu Shiqing Feng Department of Orthopedics The Second HospitalCheeloo College of MedicineShandong UniversityShandongChina Department of Orthopedics Shandong University Center for OrthopedicsQilu HospitalCheeloo College of MedicineShandong UniversityShandongChina Department of Orthopedics Tianjin Medical University General HospitalInternational Science and Technology Cooperation Base of Spinal Cord InjuryTianjin Key Laboratory of Spine and Spinal CordTianjinChina Faculty of Medicine and Health The Back Pain Research TeamSydney Musculoskeletal HealthThe Kolling InstituteUniversity of SydneySydneyNSWAustralia Department of Spine Surgery Honghui HospitalXi’an Jiaotong UniversityXi’anShaanxi ProvinceChina Department of Burns and Plastic Surgery The Fourth Medical Center of Chinese PLA General HospitalBeijingChina Faculty of Medicine and Health School of Health SciencesUniversity of SydneyNSWAustralia Sydney Spine Institute BurwoodSydneyNSWAustralia Laboratory of Epidemiology Tianjin Neurological InstituteDepartment of NeurologyTianjin Medical University General Hospital&Tianjin Neurological InstituteKey Laboratory of Post-Neuroinjury Neuro-repair and Regeneration in Central Nervous SystemMinistry of Education and Tianjin CityTianjinChina Department of Orthopedics Henan Provincial People’s HospitalZhengzhouHenan ProvinceChina Department of Spinal Surgery The Third Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Department of Orthopedics The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Spine Surgery Zhengzhou Orthopedics HospitalZhengzhouHenan ProvinceChina Department of Orthopedic Surgery and Orthopedic Research Institute West China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of Orthopedics Xinqiao HospitalArmy Medical UniversityChongqingChina Department of Orthopedics The First Affiliated Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Department of Spinal Surgery Shengj

Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even *** has the largest population of patients with traumatic spinal cord *** studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been *** the best of our knowledge,no national-level study of treatment status and economic burden has been *** retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national *** included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of *** epidemiological and clinical features,treatment status,and total and daily costs were *** in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression *** percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent *** 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 *** total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 ho

关键词： China clinical features costs epidemiology methylprednisolone sodium succinate methylprednisolone retrospective study traumatic spinal cord injury treatment

技术性压力视角下智慧图书馆人工智能风险防控体系研究

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图书馆学研究 2024年第7期 56-69页

作者：王旭程光辉赵鸿玉保林浩燕山大学经济管理学院武汉大学中国科学评价研究中心中国民航大学图书馆

人工智能在智慧图书馆的应用有效提升了服务效果,成为智慧图书馆建设的重要技术驱动力。但技术是一把双刃剑,AI应用带来的风险同样不容忽视,科学识别这些风险并建立相应的风险防控体系才可以保障智慧图书馆AI的良性利用。文章依据技术... 详细信息

人工智能在智慧图书馆的应用有效提升了服务效果,成为智慧图书馆建设的重要技术驱动力。但技术是一把双刃剑,AI应用带来的风险同样不容忽视,科学识别这些风险并建立相应的风险防控体系才可以保障智慧图书馆AI的良性利用。文章依据技术性压力理论,从人机交互层面剖析智慧图书馆中AI应用所带来的风险,并据此提出风险防控体系与对策。AI风险可以从技术与社会两个层面展开:表征技术层面的AI自身风险包括AI失控、情感断裂、AI误判、算法偏见和权责归属混乱;表征社会层面的AI衍生风险包括安全威胁、公平性挑战、版权担忧、法制缺失和职业不适应。据此构建包含风险识别、风险预警、风险治理、风险评价和风险控制效果5个层面的智慧图书馆AI风险防控体系,并从技术和管理两个方面提出了风险防控对策。

关键词：智慧图书馆人工智能技术性压力风险类型防控体系防控对策

Understanding of Five Grains for YANG:a way to straighten Asians’dietary structure

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Food and Health 2024年第3期6卷 18-19页

作者： Jing-Chao Ma Cai-Jie Zhang Wen-Li zhao Ye zhao* Intelligent Imaging College He UniversityShenyang 110163China.2 Liver CenterSaga University HospitalSaga University 849-8501Japan.3 Department of Public HealthInternational CollegeKrirk UniversityBangkok 10220Thailand.

According to the general opinion,grains should occupy the largest amount of human food each day,but this grain-based eating habit does not allow human life to be *** are high in carbohydrates and five commonly recognized plant hormones,namely auxin,gibberellin,cytokinin,abscisic acid,and *** in-depth analysis of ancient books,it was found that five grains for support:support is a restriction,and it means the essence,which means that grains should be eaten less,and it is the essence of the least daily *** correctly understand the Chinese dietary concept of"five grains for support"is the basis for improving Asian dietary health and promoting Asian human health.

关键词： Grains Hormones Carbohydrates Eating habits

Stress anisotropy regulated wrinkling pattern evolution on a core-shell soft cylinder

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Yan zhao Zhipan Jie Yilong Zhang Guoyang Li Yanping Cao Chao Jiang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan University Department of Mechanics and Engineering Science College of Engineering Peking University Institute of Biomechanics and Medical Engineering AML Department of Engineering Mechanics Tsinghua University

Diverse wrinkling patterns can occur on curved bilayer systems under differential growth or expansion. In such systems, stress anisotropy is frequently encountered, and the coupling effect of curvature and stress anisotropy on the pattern evolution remains largely unexplored. In this study, we investigate the evolution of wrinkling patterns on a cylinder core-shell system with stress anisotropy leveraging both theoretical analysis and finite element simulations. Critical buckling analysis has identified three distinct critical buckling modes regulated by the stress anisotropy, i.e., axial sinusoidal mode, checkerboard mode, and circumferential sinusoidal mode. Our finite element simulations, along with post-buckling analysis, reveal seven distinct evolutionary paths stemming from the three critical buckling modes. We present phase diagrams for both the critical buckling modes and their evolutionary paths, which are determined by dimensionless curvature and stress anisotropy. Our results not only expand the theoretical research on surface wrinkling of a core-shell soft cylinder but also introduce stress anisotropy as a significant parameter for regulating the wrinkling patterns and their evolutionary paths in curved bilayer systems. The revelation of a multitude of wrinkling patterns and their evolutionary pathways holds great potential for advancing applications that leverage tunable wrinkle surfaces.

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