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A novel cryogenic insulation system of hollow glass microspheres and self-evaporation vapor-cooled shield for liquid hydrogen storage

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Frontiers in Energy 2020年第3期14卷 570-577页

作者： Jianpeng ZHENG Liubiao CHEN Ping WANG Jingjie ZHANG Junjie WANG yuan zhou Chinese Academy of Sciences Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China Chinese Academy of Sciences State Key Laboratory of Technologies in Space Cryogenic Propellants Technical Institute of Physics and ChemistryBeijing 100190China

Liquid hydrogen(LH2)attracts widespread attention because of its highest energy storage density.However,evaporation loss is a serious problem in LH2 storage due to the low boiling point(20 K).Efficient insulation technology is an important issue in the study of LH2 storage.Hollow glass microspheres(HGMs)is a potential promising thermal insulation material because of its low apparent thermal conductivity,fast installation(Compared with multi-layer insulation,it can be injected in a short time.),and easy maintenance.A novel cryogenic insulation system consisting of HGMs and a selfevaporating vapor-cooled shield(VCS)is proposed for storage of LH2.A thermodynamic model has been established to analyze the coupled heat transfer characteristics of HGMs and VCS in the composite insulation system.The results show that the combination of HGMs and VCS can effectively reduce heat flux into the LH2 tank.With the increase of VCS number from 1 to 3,the minimum heat flux through HGMs decreases by 57.36%,65.29%,and 68.21%,respectively.Another significant advantage of HGMs is that their thermal insulation properties are not sensitive to ambient vacuum change.When ambient vacuum rises from 10^-3 Pa to 1 Pa,the heat flux into the LH2 tank increases by approximately 20%.When the vacuum rises from 10^-3 Pa to 100 Pa,the combination of VCS and HGMs reduces the heat flux into the tank by 58.08%-69.84% compared with pure HGMs.

关键词： liquid hydrogen storage hollow glass microspheres(HGMs) self-evaporation vapor-cooled shield(VCS) thermodynamic optimization

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基于地理探测器和随机森林模型的区域景观游憩服务潜在供应评估方法研究——以亚热带湿润淮阳低山景观区为例

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生态学报 2024年第13期44卷 5629-5645页

作者：李业涵周媛吴雪飞华中农业大学园艺林学学院武汉430070

游憩服务(RS)是自然对人类的贡献(NCP)之一,也是区域尺度下主要的人类需求,由于其具有无形、主观、非物质等特点,量化RS一直是当前研究的难点与热点。既往研究的评估方法依赖于利益相关者的认知,缺乏通用性,并多为对各类土地类型或植被... 详细信息

游憩服务(RS)是自然对人类的贡献(NCP)之一,也是区域尺度下主要的人类需求,由于其具有无形、主观、非物质等特点,量化RS一直是当前研究的难点与热点。既往研究的评估方法依赖于利益相关者的认知,缺乏通用性,并多为对各类土地类型或植被的RS潜在供应能力进行“一刀切”式直接赋值,鲜有考虑地域特征。研究旨在探究景观特征及其要素如何影响RS供给,从而提出一种因地制宜的RS潜在供应量客观评估方法。以“亚热带湿润淮阳低山景观区”为例,首先将风景资源点分为5类,利用核密度分析量化各类RS实际供应;然后利用地理探测器分类评估景观特征的RS贡献度;再基于随机森林模型对景观特征要素与RS潜在供应能力进行关联量化分析;最后测算出各景观类型的RS潜在供应量。研究结果表明:(1)不同景观特征的RS贡献度具有差异,不同景观特征要素具备不同的RS潜在供应能力;(2)景观特征的RS贡献度和景观特征要素的RS潜在供应能力在不同地理气候条件下具有空间分异特征,应当因地制宜进行评估;(3)景观特征的贡献度和景观特征要素的RS潜在供应能力取决于RS的类型,在评估RS潜在供应量时,应对RS进行分类探讨;(4)由于景观类型是景观特征要素的聚类簇,基于景观类型测算RS潜在供应量可以反映出若干景观特征要素RS潜在供应能力的协同性。强调了景观特征及其要素在RS评估方面的关键作用,所提出的量化方法突破了主观性的局限,具有客观优势,最终可为全域旅游规划和风景资源点建设选址提供参考。

关键词：游憩服务区域景观景观特征景观特征要素地理探测器随机森林模型

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川藏滇青民族服饰研究对铸牢中华民族共同体意识的价值思考

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服装论丛 2024年第1期19卷 61-68页

作者：周裕兰四川民族学院美术学院四川康定626001

针对川藏滇青民族服饰研究如何有利于铸牢中华民族共同体意识,采用文献整理方法,从历史的角度,对川藏滇青民族服饰进行了梳理和分析,得到川藏滇青民族服饰研究是有利于积极落实、落细、落小、落巧“铸牢中华民族共同体意识”这一民族工... 详细信息

针对川藏滇青民族服饰研究如何有利于铸牢中华民族共同体意识,采用文献整理方法,从历史的角度,对川藏滇青民族服饰进行了梳理和分析,得到川藏滇青民族服饰研究是有利于积极落实、落细、落小、落巧“铸牢中华民族共同体意识”这一民族工作重大命题的全民化、生活化、国际化举措。研究表明,对川藏滇青民族服饰的研究和保护,有利于在弘扬优秀的民族服饰文化的基础上,增强国家意识和民族团结意识,增强中华各民族的凝集力,铸牢中华民族共同体意识。

关键词：川藏滇青民族服饰中华民族共同体意识价值

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社交媒介视角下城市文创园区的空间重塑研究——以上海为例

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地理研究 2024年第5期43卷 1166-1186页

作者：崔璐明汪明峰周媛张英浩华东师范大学中国现代城市研究中心上海200062 华东师范大学中国行政区划研究中心上海200241 华东师范大学地理科学学院上海200241 上海城市房地产估价有限公司上海200003 山东理工大学经济学院淄博255012

在数字化时代,社交媒介促进了实体空间与数字空间的连接和融合,也影响了人与地方环境的互动关系。本文基于网络信息地理学和媒介地理学的理论基础,构建社交媒介与空间重塑的“存在-膨胀-符号化”分析框架,以上海市认定的文创园区为研究... 详细信息

在数字化时代,社交媒介促进了实体空间与数字空间的连接和融合,也影响了人与地方环境的互动关系。本文基于网络信息地理学和媒介地理学的理论基础,构建社交媒介与空间重塑的“存在-膨胀-符号化”分析框架,以上海市认定的文创园区为研究对象,选取抖音和小红书两个社交媒介平台中的用户生成内容(user-generated content,UGC)为研究数据,探究社交媒介对城市文创园区的空间重塑作用,为城市更新进程中文创园区的数字化发展提供政策启示。研究发现:(1)社交媒介的作用在于引导用户行为,将实体文创园区数字化为媒介平台中的地点。(2)基于UGC产生的广泛热度和偏好热度加剧了数字空间的膨胀。(3)打卡者在社交媒介中持续地对数字空间中的文创园区进行意象叠加与更新,形成了符号化的空间形象。(4)社交媒介中不断生成的UGC重塑人们对实体空间与数字空间的认知意象,进一步创造了超越两种空间的数字地方。如此,社交媒介通过“线下→线上→数字地方→数字→实体”的循环路径对文创园区进行空间重塑。

关键词：社交媒介文创园区空间重塑符号化数字地方

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Protecting Cell Walls from Binding Aluminum by Organic Acids Contributes to Aluminum Resistance

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Journal of Integrative Plant Biology 2009年第6期51卷 574-580页

作者： Ya-Ying Li Yue-Jiao Zhang yuan zhou Jian-Li Yang Shao-Jian Zheng Ministry of Agriculture Key Laboratory for Non-Point Pollution Control Zhejiang University Hangzhou 310029 China State Key Laboratory of Plant Physiology and Biochemistry College of Life Sciences Zhejiang University Hangzhou 310058 China

Aluminum-induced secretion of organic acids from the root apex has been demonstrated to be one major AI resistance mechanism in plants. However, whether the organic acid concentration is high enough to detoxify AI in the growth medium is frequently questioned. The genotypes of AI-resistant wheat, Cassia tora L. and buckwheat secrete malate, citrate and oxalate, respectively. In the present study we found that at a 35% inhibition of root elongation, the AI activities in the solution were 10, 20, and 50 μM with the corresponding malate, citrate, and oxalate exudation at the rates of 15, 20 and 21 nmol/cm2 per 12 h, respectively, for the above three plant species. When exogenous organic acids were added to ameliorate AI toxicity, twofold and eightfold higher oxalate and malate concentrations were required to produce the equal effect by citrate. After the root apical cell walls were isolated and preincubated in 1 mM malate, oxalate or citrate solution overnight, the total amount of AI adsorbed to the cell walls all decreased significantly to a similar level, implying that these organic acids own an equal ability to protect the cell walls from binding AI. These findings suggest that protection of cell walls from binding AI by organic acids may contribute significantly to AI resistance.

关键词： adsorption and desorption aluminum toxicity cell wall chelation detoxification organic acid.

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An experimental method for measuring friction behaviors of linear rolling guides

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Chinese Science Bulletin 2014年第29期59卷 3912-3918页

作者： Yinhu Xi yuan zhou Wei Zhang Junhong Mao Theory of Lubrication and Bearing Institute Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing SystemSchool of Mechanical EngineeringXi’an Jiaotong University

Friction behaviors of linear rolling guides(LRGs)are determined by many factors and are crucial for precision positioning.It is difficult to create an expression to describe the friction behaviors exactly and completely.A new experimental method for measuring the friction behaviors of one LRG individually was developed,and linear motor direct drive technology is utilized in the experiment setup.The position signal is acquired by a grating,and the friction of the LRG is deduced by the product of the mass of the moving part and its acceleration.In the experiment,the LRG can move with the friction only,and the friction transition from normal rolling to prerolling stage was detected.The asperities’deformations were utilized to explain it.Hysteresis loops and internal loops were measured.The results indicate the non-local memory of the LRG,and the historical trajectory have an important impact on the friction behaviors of LRGs in the pre-rolling stage.

关键词：直线滚动导轨摩擦行为测量验方精确定位驱动技术直线电机位置信号

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Wasserstein GAN-Based Small-Sample Augmentation for New-Generation Artificial Intelligence: A Case Study of Cancer-Staging Data in Biology

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Engineering 2019年第1期5卷 156-163页

作者： Yufei Liu yuan zhou Xin Liu Fang Dong Chang Wang Zihong Wang College of Life Science and Technology Huazhong University of Science and Technology Wuhan 430074 China School of Public Policy and Management Tsinghua University Beijing 100084 China School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China Center for Strategic Studies Chinese Academy of Engineering Beijing 100088 China

It is essential to utilize deep-learning algorithms based on big data for the implementation of the new generation of artificial intelligence. Effective utilization of deep learning relies considerably on the number of labeled samples, which restricts the application of deep learning in an environment with a small sample size. In this paper, we propose an approach based on a generative adversarial network (GAN) combined with a deep neural network (DNN). First, the original samples were divided into a training set and a test set. The GAN was trained with the training set to generate synthetic sample data, which enlarged the training set. Next, the DNN classifier was trained with the synthetic samples. Finally, the classifier was tested with the test set, and the effectiveness of the approach for multi-classification with a small sample size was validated by the indicators. As an empirical case, the approach was then applied to identify the stages of cancers with a small labeled sample size. The experimental results verified that the proposed approach achieved a greater accuracy than traditional methods. This research was an attempt to transform the classical statistical machine-learning classification method based on original samples into a deep-learning classification method based on data augmentation. The use of this approach will contribute to an expansion of application scenarios for the new generation of artificial intelligence based on deep learning, and to an increase in application effectiveness. This research is also expected to contribute to the comprehensive promotion of new-generation artificial intelligence.

关键词： Artificial intelligence Generative adversarial network Deep neural network Small sample size Cancer

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Identification and fine mapping of quantitative trait loci for seed vigor in germination and seedling establishment in rice

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Journal of Integrative Plant Biology 2014年第8期56卷 749-759页

作者： Lixia Xie Zhengwei Tan yuan zhou Rongbao Xu Laibao Feng Yongzhong Xing Xiaoquan Qi Key Laboratory of Plant Molecular Physiology Institute of Botany the Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Continuing Education Shandong Television University National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University

Seed vigor is an index of seed quality that is used to describe the rapid and uniform germination and the establish- ment of strong seedlings in any environmental conditions. Strong seed vigor in low-temperature germination conditions is particularly important in direct-sowing rice production systems. However, seed vigor has not been selected as an important breeding trait in traditional breeding programs due to its quantitative inherence. In this study, we identified and mapped eight quantitative trait loci （QTLs） for seed vigor by using a recombinant inbred population from a cross between rice （Oryza sativa L. ssp. indica） cultivars ZS97 and MH63. Conditional QTL analysis identified qSV-1, qSV-Sb, qSV-6a, qSV- 6b, and qSV-11 influenced seedling establishment and that qSV- 5a, qSV-Sc, and qSV-8 influenced only germination. Of these, qSV-1, qSV-Sb, qSV-6a, qSV-6b, and qSV-8 were low-tempera- ture-specific QTLs. Two major-effective QTLs, qSV-1, and qSV-5cwere narrowed down to 1.13-Mbp and 4oo-kbp genomic regions, respectively. The results provide tightly linked DNA markers for the marker-assistant pyramiding of multiple positive alleles for increased low-temperature germination seed vigor in both normal and environments.

关键词： Conditional quantitative trait locus mapping germination seedling establishment seed vigor rice

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数控机床切削过程中的振动分析与控制策略研究

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模具制造 2024年第5期24卷 246-248页

作者：周嫄贵州航空工业技师学院贵州贵阳550000

数控机床切削过程中振动问题成因复杂且对切削加工精度、质量、效率等有较大影响。梳理了数控机床切削的振动的影响因素、振动机理、振动衡量等基础概念,以及金属切削过程的主动、被动和半主动颤振控制技术;从数控机床切削颤振控制技术... 详细信息

数控机床切削过程中振动问题成因复杂且对切削加工精度、质量、效率等有较大影响。梳理了数控机床切削的振动的影响因素、振动机理、振动衡量等基础概念,以及金属切削过程的主动、被动和半主动颤振控制技术;从数控机床切削颤振控制技术发展、控制逻辑以及基于数理模型的控制模型建构逻辑角度等探讨颤振的控制策略,并从系统动力学、多元数据融合、智能控制等角度予解释。

关键词：数控机床切削过程振动分析控制策略

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The role of viral protein Ac34 in nuclear relocation of subunits of the actin-related protein 2/3 complex

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Virologica Sinica 2016年第6期31卷 480-489页

作者： Jingfang Mu Yongli Zhang Yangyang Hu Xue Hu yuan zhou Xinwen Chen Yun Wang State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China University of Chinese Academy of Sciences Beijing 100049 China

The actin nucleator actin-related protein complex(Arp2/3) is composed of seven subunits: Arp2,Arp3, p40/ARPC1(P40), p34/ARPC2(P34), p21/ARPC3(P21), p20/ARPC4(P20), and p16/ARPC5(P16). Arp2/3 plays crucial roles in a variety of cellular activities through regulation of actin polymerization. Autographa californica multiple nucleopolyhedrovirus(Ac MNPV), one of the beststudied alphabaculoviruses, induces Arp2/3 nuclear relocation and mediates nuclear actin polymerization to assist in virus replication. We have demonstrated that Ac34, a viral late-gene product, induces translocation of the P40 subunit of Arp2/3 to the nucleus during Ac MNPV infection. However, it remains unknown whether Ac34 could relocate other Arp2/3 subunits to the nucleus. In this study, the effects of the viral protein Ac34 on the distribution of these subunits were studied by an immunofluorescence assay. Arp2, P34, P21, and P20 cloned from Spodoptera frugiperda(Sf9) cells showed mainly cytoplasmic localization and were relocated to the nucleus in the presence of Ac34. In addition, Arp3 was localized in the cytoplasm in both the presence and absence of Ac34, and P16 showed whole-cell localization. In contrast to Sf9 cells, all subunits of mammalian Arp2/3 showed no nuclear relocation in the presence of Ac34. Co-immunoprecipitation analysis of the interaction between Ac34 and Arp2/3 subunits revealed that Ac34 bound to P40,P34, and P20 of Sf9 cells. However, none of the subunits of mammalian Arp2/3 interacted with Ac34, indicating that protein-protein interaction is essential for Ac34 to relocate Arp2/3 subunits to the nucleus.

关键词： Autographa californica multiple nucleopolyhedrovirus(AcMNPV) Ac34 Arp2/3 complex nuclear relocation

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