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基于NV色心的钢轨裂纹检测分析
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作者 范华林 史红兵 +9 位作者 赵博文 董亮亮 程江辉 王仁涛 谢赛南 张鸣山 肖久华 张少春 沈忆华 周梦良 《无损检测》 2026年第1期70-73,79,共5页
目前大多使用人工检测和超声检测对钢轨进行在线检测,钢轨裂纹宽度及深度的检测精度为毫米级,对开口小、深度浅的微米级钢轨裂纹尚未有合适的检测方法。针对此不足,提出基于金刚石氮-空位(Nitrogen-vacancy,NV)色心的钢轨裂纹检测方法,... 目前大多使用人工检测和超声检测对钢轨进行在线检测,钢轨裂纹宽度及深度的检测精度为毫米级,对开口小、深度浅的微米级钢轨裂纹尚未有合适的检测方法。针对此不足,提出基于金刚石氮-空位(Nitrogen-vacancy,NV)色心的钢轨裂纹检测方法,并研制相应的漏磁-量子检测装置。针对钢轨表面的裂纹,使用永磁铁磁化钢轨表面,通过NV色心对磁的高灵敏度和高分辨率特性检测钢轨表面裂纹漏磁信号。选取锰钢钢轨,在表面设计并加工横向裂纹,配合设计的钢轨探伤车进行检测试验。试验结果表明,试验装置的测量灵敏度为7nT/√Hz,可以完成最小宽度为100 um,深度为100 um的钢轨表面裂纹检测。 展开更多
关键词 钢轨 裂纹检测 漏磁检测 nv色心
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褒贬反转构式“这NV的”的语篇承继关联及话语功能
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作者 朱敏 《语文学刊》 2025年第1期60-68,共9页
“这NV的”是一个将积极义和消极义集于一身的主观评价构式。它表示积极评价时是有标记的,而表示消极评价时是无标记的。从语篇承继关联的角度看,“这NV的”的语义整合可以分为四级,从低整合度到高整合度的承继过程体现了“渐变性”特... “这NV的”是一个将积极义和消极义集于一身的主观评价构式。它表示积极评价时是有标记的,而表示消极评价时是无标记的。从语篇承继关联的角度看,“这NV的”的语义整合可以分为四级,从低整合度到高整合度的承继过程体现了“渐变性”特征。补语的脱落、前景提示的消失、积极义的有标记性和消极义的无标记性都体现了语言经济性的特点。说话人使用“这NV的”来凸显某事态的主观超量特征,并体现出说话人爱憎分明的评价特点,表达出委婉含蓄的言外之意。 展开更多
关键词 “这nv的” 承继 理据 话语功能 语言经济性
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A Trusted Mobile Payment Environment Based on Trusted Computing and Virtualization Technology 被引量:2
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作者 WANG Juan LIN Wutao +3 位作者 LI Haoyu DU Bianxia MENG Ke WANG Jiang 《Wuhan University Journal of Natural Sciences》 CAS 2014年第5期379-384,共6页
In this paper, we propose a trusted mobile payment environment (TMPE) based on trusted computing and virtualization technology. There are a normal operating system (OS) and a trusted OS (TOS) in TMPE. We store t... In this paper, we propose a trusted mobile payment environment (TMPE) based on trusted computing and virtualization technology. There are a normal operating system (OS) and a trusted OS (TOS) in TMPE. We store the image of TOS in a memory card to hinder tampering. The integrity of TOS is protected by means of a trusted platform module (TPM). TOS can only be updated through a trusted third party. In addition, virtualization technology is applied to isolate TOS from normal OS. Users complete ordinary affairs in normal OS and security-sensitive affairs in TOS. TMPE can offer users a highly protected environment for mobile payment. Moreover, TMPE has good compatibility in different hardware architectures of mobile platforms. As the evaluation shows, TMPE satisfies the requirement of mobile payment well. 展开更多
关键词 trusted computing mobile payment virtualization mobile platform
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面向NV色心宽带微波传感系统的天线设计 被引量:1
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作者 柯冬倩 武炳地 马宗敏 《传感器与微系统》 北大核心 2025年第4期78-82,共5页
宽频带微波探测在无线通信、遥感以及医学成像等领域至关重要。金刚石氮-空位(NV)色心因其高稳定性和高灵敏度等优势成为微波检测的热门选择。但现在用于NV传感器的天线存在信号传输质量差和频带窄等问题。本文设计了多谐振频率环形天线... 宽频带微波探测在无线通信、遥感以及医学成像等领域至关重要。金刚石氮-空位(NV)色心因其高稳定性和高灵敏度等优势成为微波检测的热门选择。但现在用于NV传感器的天线存在信号传输质量差和频带窄等问题。本文设计了多谐振频率环形天线组,结合宽场成像技术与光学探测磁场共振(ODMR)技术构建了金刚石微波频谱检测系统,对磁场引起的ODMR共振频率的偏移进行空间编码进而探测微波。实验结果表明:所设计的天线组在增强电子自旋共振(ESR)对比度方面表现优异,达到13%,比传统宽频带螺旋天线提高了5.5%,并实现了2.2~10.0 GHz范围的微波频谱检测。该设计为NV量子传感器多频段微波探测技术的发展提供了新思路。 展开更多
关键词 nv色心 宽带天线 微波检测 量子传感
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Security Challenges of Virtualization Hypervisors in Virtualized Hardware Environment 被引量:1
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作者 Gabriel Cephas Obasuyi Arif Sari 《International Journal of Communications, Network and System Sciences》 2015年第7期260-273,共14页
The concept of virtualization machines is not new, but it is increasing vastly and gaining popularity in the IT world. Hypervisors are also popular for security as a means of isolation. The virtualization of informati... The concept of virtualization machines is not new, but it is increasing vastly and gaining popularity in the IT world. Hypervisors are also popular for security as a means of isolation. The virtualization of information technology infrastructure creates the enablement of IT resources to be shared and used on several other devices and applications;this increases the growth of business needs. The environment created by virtualization is not restricted to any configuration physically or execution. The resources of a computer are shared logically. Hypervisors help in virtualization of hardware that is a software interact with the physical system, enabling or providing virtualized hardware environment to support multiple running operating system simultaneously utilizing one physical server. This paper explores the benefits, types and security issues of Virtualization Hypervisor in virtualized hardware environment. 展开更多
关键词 virtualization Hypervisors VIRTUAL MACHINE VIRTUAL MACHINE MONITOR SECURITY
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基于频率调制参数优化的高灵敏NV色心磁测量技术研究
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作者 郑斗斗 王珲 +3 位作者 高健 李洋 杨应杰 马宗敏 《量子光学学报》 北大核心 2025年第1期33-41,共9页
金刚石氮空位(NV)色心在磁场测量领域展现出显著的高灵敏度和高分辨率等优势。为了解决传统的光探测磁共振(ODMR)方法无法实现待测磁场高灵敏度实时检测等问题,近年来基于微波频率调制技术的NV色心磁测量方法受到广泛关注和研究,然而最... 金刚石氮空位(NV)色心在磁场测量领域展现出显著的高灵敏度和高分辨率等优势。为了解决传统的光探测磁共振(ODMR)方法无法实现待测磁场高灵敏度实时检测等问题,近年来基于微波频率调制技术的NV色心磁测量方法受到广泛关注和研究,然而最优调制频率和调制频偏参数不明晰成为了限制NV色心磁强计灵敏度的重要因素之一。本文通过建立解调信号模型,结合仿真得到了理论最优调制频偏参数。经过实验验证,得到最佳调制频率参数为500 Hz及1 kHz至2 kHz范围,调制频偏为8 MHz,由于色心浓度及微波不均匀导致的共振谱展宽限制了其与理论结果的匹配度,但调制频偏参数的变化趋势在仿真和实验结果中表现一致。本研究为NV色心磁强计的灵敏度指标提升提供了理论指导和实验经验。 展开更多
关键词 nv色心 调制频率 调制频偏 灵敏度
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金刚石中的NV色心制备和应用研究
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作者 伍正新 满卫东 +4 位作者 贾元波 梁凯 范冰庆 付萍 赵洪阳 《广州化工》 2025年第6期45-48,共4页
金刚石中的氮空位(NV)中心是一种固态缺陷量子比特,在室温下具有良好的相干时间,可用于多种量子传感器和生物领域的应用。在量子计算和通信中也具有潜在的应用价值。量子控制在很大程度上取决于NV中心的电子结构和状态的复杂细节,这些... 金刚石中的氮空位(NV)中心是一种固态缺陷量子比特,在室温下具有良好的相干时间,可用于多种量子传感器和生物领域的应用。在量子计算和通信中也具有潜在的应用价值。量子控制在很大程度上取决于NV中心的电子结构和状态的复杂细节,这些状态之间的辐射和非辐射速率,以及这些状态与外部自旋、电场、磁场和应变场以及温度的耦合。近年来,量子传感器测温的灵敏度随着NV色心制备工艺的优化而得到巨大提升,在显微成像领域也取得很大成果。本文首先介绍了NV色心的结构和基本特性,并对其制备方法和应用研究进行了总结。 展开更多
关键词 金刚石 nv色心 量子比特 量子传感
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基于 NV 色心的弱磁场扫描成像实验
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作者 袁竟程 王涛 +2 位作者 张军伟 刘心宇 杜关祥 《佳木斯大学学报(自然科学版)》 2025年第2期174-176,33,共4页
为适应当下芯片复杂度、集成度提升的发展趋势,亟需一种高分辨精密磁场成像系统。基于NV色心实现的新式磁场扫描系统可在室温下完成高分辨率、高灵敏度的弱磁场扫描成像,且测量过程不产生电磁干扰,填补了传统磁场测量技术的空白。设计... 为适应当下芯片复杂度、集成度提升的发展趋势,亟需一种高分辨精密磁场成像系统。基于NV色心实现的新式磁场扫描系统可在室温下完成高分辨率、高灵敏度的弱磁场扫描成像,且测量过程不产生电磁干扰,填补了传统磁场测量技术的空白。设计了两个基于NV色心的弱磁场扫描实验,以期为NV色心磁场扫描成像装置的研发提供参考。 展开更多
关键词 nv色心 磁成像 脉冲光探测磁共振 拉比振荡
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Resource Virtualization Model Using Hybrid-graph Representation and Converging Algorithm for Cloud Computing
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作者 Quan Liang Yuan-Zhuo Wang Yong-Hui Zhang 《International Journal of Automation and computing》 EI CSCD 2013年第6期597-606,共10页
Cloud computing can provide a great capacity for massive computing, storage as well as processing. The capacity comes from the cloud computing system itself, which can be likened to a virtualized resource pool that su... Cloud computing can provide a great capacity for massive computing, storage as well as processing. The capacity comes from the cloud computing system itself, which can be likened to a virtualized resource pool that supports virtualization applications as well as load migration. Based on the existing technologies, the paper proposes a resource virtualization model (RVM) utilizing a hybrid-graph structure. The hybrid-graph structure can formally represent the critical entities such as private clouds, nodes within the private clouds, and resource including its type and quantity. It also provides a clear description of the logical relationship and the dynamic expansion among them as well. Moreover, based on the RVM, a resource converging algorithm and a maintaining algorithm of the resource pool which can timely reflect the dynamic variation of the private cloud and resource are presented. The algorithms collect resources and put them into the private cloud resource pools and global resource pools, and enable a real-time maintenance for the dynamic variation of resource to ensure the continuity and reliability. Both of the algorithms use a queue structure to accomplish functions of resource converging. Finally, a simulation platform of cloud computing is designed to test the algorithms proposed in the paper. The results show the correctness and the reliability of the algorithms. 展开更多
关键词 Cloud computing resource virtualization hybrid graph resource converging simulation.
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金刚石NV-色心中近红外光对自旋电荷态转换的影响研究
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作者 胡钧 钱鹏 +2 位作者 张恒 张杨 马钰 《合肥工业大学学报(自然科学版)》 北大核心 2025年第8期1112-1116,共5页
文章利用近红外光对532 nm激光照射金刚石氮空位(nitrogen-vacancy,NV)色心产生的荧光时间轨迹进行调制,发现不同电子自旋初态下的调制深度并不相同;由于589 nm激光只激发处于负电性电荷态的色心(NV-色心),进而研究不同功率的589 nm激... 文章利用近红外光对532 nm激光照射金刚石氮空位(nitrogen-vacancy,NV)色心产生的荧光时间轨迹进行调制,发现不同电子自旋初态下的调制深度并不相同;由于589 nm激光只激发处于负电性电荷态的色心(NV-色心),进而研究不同功率的589 nm激光单独激发色心和加入近红外光共同激发色心导致的电荷态布居变化。实验结果表明,近红外光能够加快NV-色心电离的过程,但是不同电子自旋初态导致的电离速率有所差异,造成该差异的原因可能是近红外光对NV-色心自旋单态的电离比激发态的电离具有更高的效率。文章研究结果对基于金刚石NV-色心的自旋量子态读出和量子精密测量具有重要意义。 展开更多
关键词 氮空位(nv)色心 电荷态 近红外光 自旋态
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Investigating the Implications of Virtualization for Digital Forensics
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作者 Song Zheng Jin Bo +1 位作者 Zhu Yinghong Sun Yongqing 《China Communications》 SCIE CSCD 2010年第6期100-106,共7页
Research in virtualization technology has gained significant developments in recent years, which brings not only opportunities to the forensic community, but challenges as well. This paper discusses the potential role... Research in virtualization technology has gained significant developments in recent years, which brings not only opportunities to the forensic community, but challenges as well. This paper discusses the potential roles of virtualization in digital forensics, examines the recent progresses which use the virtualization techniques to support modem computer forensics. The influences on digital forensics caused by virtualization technology are identified. Tools and methods in common digital forensic practices are analyzed, and experiences of our practice and reflections in this field are shared. 展开更多
关键词 digital forensics virtualization forensic image booting virtual machine introspection
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A Concurrent Security Monitoring Method for Virtualization Environments
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作者 TIAN Donghai JIA Xiaoqi +1 位作者 CHEN Junhua HU Changzhen 《China Communications》 SCIE CSCD 2016年第1期113-123,共11页
Recently,virtualization technologies have been widely used in industry.In order to monitor the security of target systems in virtualization environments,conventional methods usually put the security monitoring mechani... Recently,virtualization technologies have been widely used in industry.In order to monitor the security of target systems in virtualization environments,conventional methods usually put the security monitoring mechanism into the normal functionality of the target systems.However,these methods are either prone to be tempered by attackers or introduce considerable performance overhead for target systems.To address these problems,in this paper,we present a concurrent security monitoring method which decouples traditional serial mechanisms,including security event collector and analyzer,into two concurrent components.On one hand,we utilize the SIM framework to deploy the event collector into the target virtual machine.On the other hand,we combine the virtualization technology and multi-core technology to put the event analyzer into a trusted execution environment.To address the synchronization problem between these two concurrent components,we make use of Lamport's ring buffer algorithm.Based on the Xen hypervisor,we have implemented a prototype system named COMO.The experimental results show that COMO can monitor the security of the target virtual machine concurrently within a little performance overhead. 展开更多
关键词 security virtualization technology concurrent monitoring
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Unveiling and swift diagnosing chronic wound healing with artificial intelligence assistance 被引量:1
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作者 Jiliang Deng Guoliang Shi +5 位作者 Zhihang Ye Quan Xiao Xiaoting Zhang Lei Ren Fangyu Yang Miao Wang 《Chinese Chemical Letters》 2025年第3期469-475,共7页
Histopathological analysis of chronic wounds is crucial for clinicians to accurately assess wound healing progress and detect potential malignancy.However,traditional pathological tissue sections require specific stai... Histopathological analysis of chronic wounds is crucial for clinicians to accurately assess wound healing progress and detect potential malignancy.However,traditional pathological tissue sections require specific staining procedures involving carcinogenic chemicals.This study proposes an interdisciplinary approach merging materials science,medicine,and artificial intelligence(AI)to develop a virtual staining technique and intelligent evaluation model based on deep learning for chronic wound tissue pathology.This innovation aims to enhance clinical diagnosis and treatment by offering personalized AI-driven therapeutic strategies.By establishing a mouse model of chronic wounds and using a series of hydrogel wound dressings,tissue pathology sections were periodically collected for manual staining and healing assessment.We focused on leveraging the pix2pix image translation framework within deep learning networks.Through CNN models implemented in Python using PyTorch,our study involves learning and feature extraction for region segmentation of pathological slides.Comparative analysis between virtual staining and manual staining results,along with healing diagnosis conclusions,aims to optimize AI models.Ultimately,this approach integrates new metrics such as image recognition,quantitative analysis,and digital diagnostics to formulate an intelligent wound assessment model,facilitating smart monitoring and personalized treatment of wounds.In blind evaluation by pathologists,minimal disparities were found between virtual and conventional histologically stained images of murine wound tissue.The evaluation used pathologists’average scores on real stained images as a benchmark.The scores for virtual stained images were 71.1%for cellular features,75.4%for tissue structures,and 77.8%for overall assessment.Metrics such as PSNR(20.265)and SSIM(0.634)demonstrated our algorithms’superior performance over existing networks.Eight pathological features such as epidermis,hair follicles,and granulation tissue can be accurately identified,and the images were found to be more faithful to the actual tissue feature distribution when compared to manually annotated data. 展开更多
关键词 Chronic wound Virtual pathological staining AI-assisted diagnostic and therapeutic Gel dressings
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Three-dimensional localization of the individual shallow NV center in diamond using a gold tip
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作者 Jiarui Qi Xinghang Chen +1 位作者 Mengqi Wang Ya Wang 《中国科学技术大学学报》 北大核心 2025年第4期35-39,34,I0002,共7页
This work presents a method for the three-dimensional localization of individual shallow NV center in diamond,leveraging the near-field quenching effect of a gold tip.Our experimental setup involves the use of an atom... This work presents a method for the three-dimensional localization of individual shallow NV center in diamond,leveraging the near-field quenching effect of a gold tip.Our experimental setup involves the use of an atomic force microscope to precisely move the gold tip close to the NV center,while simultaneously employing a home-made confocal microscope to monitor the fluorescence of the NV center.This approach allows for lateral super-resolution,achieving a full width at half maximum(FWHM)of 38.0 nm and a location uncertainty of 0.7 nm.Additionally,we show the potential of this method for determining the depth of the NV centers.We also attempt to determine the depth of the NV centers in combination with finite-difference time-domain(FDTD)simulations.Compared to other depth determination methods,this approach allows for simultaneous lateral and longitudinal localization of individual NV centers,and holds promise for facilitating manipulation of the local environment surrounding the NV center. 展开更多
关键词 nv center super-resolution localization atom force microscopy
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基于金刚石NV色心的免微波磁平衡直流测量应用
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作者 张少春 赵博文 +3 位作者 刘雅琪 赵冀红 童晓枫 周梦良 《微纳电子技术》 2025年第3期142-150,共9页
随着特高压技术的发展,电力系统对电流互感器的安全性和可靠性提出了更高的要求。近年来,基于量子精密测量技术的金刚石氮-空位(NV)色心电流互感器凭借其高精度、高灵敏度的特点,得到了广泛的研究与应用。提出了一种基于金刚石NV色心的... 随着特高压技术的发展,电力系统对电流互感器的安全性和可靠性提出了更高的要求。近年来,基于量子精密测量技术的金刚石氮-空位(NV)色心电流互感器凭借其高精度、高灵敏度的特点,得到了广泛的研究与应用。提出了一种基于金刚石NV色心的磁平衡直流电流测量方案,利用平衡线圈产生的磁场平衡待测电流激发的磁场,并采用调制线圈跟踪平衡点的变化,通过校准后实现电流测量功能。进行了500、1000和5000 A的精度测试,所设计的直流电流测量精度突破了0.2%,对于应用推广具有重要意义。 展开更多
关键词 金刚石 氮-空位(nv)色心 磁平衡 量子精密测量 互感器
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基于金刚石NV色心宽场显微磁成像系统的研制
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作者 王东 许艳丽 +4 位作者 周玉国 罗惠恒 陈典龙 单隆坤 付天阅 《微纳电子技术》 2025年第11期96-104,共9页
磁性材料的显微磁成像对于研究材料的磁学性质具有重要意义。搭建了宽场显微镜磁场矢量成像系统,该系统基于金刚石氮-空位(NV)色心,采用光检测磁共振(ODMR)原理,通过对荧光变化的收集分析,能够获取金刚石NV色心电子自旋基态的共振频率... 磁性材料的显微磁成像对于研究材料的磁学性质具有重要意义。搭建了宽场显微镜磁场矢量成像系统,该系统基于金刚石氮-空位(NV)色心,采用光检测磁共振(ODMR)原理,通过对荧光变化的收集分析,能够获取金刚石NV色心电子自旋基态的共振频率。对地质样品切片进行了磁成像实验,对比度图上可见明显的、随测量频率变化的磁偶分布,在矢量成像结果中,能看到较明显的磁性区域,磁性区域周围ODMR谱线存在劈裂变化,并且该变化在磁偶区域呈现相反的趋势。根据ODMR谱图进行计算,该系统磁场探测灵敏度为3.2274861μT/√Hz,成像分辨率为533 nm。 展开更多
关键词 氮-空位(nv)色心 宽场显微镜 光检测磁共振(ODMR) 磁性材料 磁场矢量成像
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Impacts of China food trade on global resource and environment:A sustainable development assessment
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作者 Xiang Wang Xin Li +3 位作者 Libang Ma Jing Bai Li Li Simin Yan 《Geography and Sustainability》 2025年第6期101-114,共14页
Meeting China's burgeoning food demand while safeguarding the resources and environmental long-term development is a critical challenge for the sustainable food systems of this century.China's accelerated food... Meeting China's burgeoning food demand while safeguarding the resources and environmental long-term development is a critical challenge for the sustainable food systems of this century.China's accelerated food imports have far-reaching implications for global resource allocation and environmental development.Hence,detailed information regarding China's food trade resource-environmental impacts is imperative for the design of effective policies that promote environmental mitigation and resource conservation.This study estimated the spatial transfers of virtual water trade(VWT),virtual land trade(VLT),and virtual GHG emission trade(VGT)embodied in China's food trade.Findings indicate that the VWT,VLT,and VGT transfers embodied in China's food trade increased by 10.4%,9.8%,and 15.2%annually.It is more important to mention that virtual water import(VWI)and virtual land import(VLI)saved 119.5×10~9m^(3)of global water resources and 29.5 Mha of land resources,respectively,but virtual GHG emission import(VGI)increased global 13 Mt CO_(2)-eq GHG emissions.The divergent impacts of China's food import on global food sustainability stem from variations in virtual water content,yields and emission intensities.Moreover,significant differences in sustainability scores were found among the top 15 importing countries,indicating that China's food trade contributes to the deepening of global food system sustainability.This study highlights the need for a multifaceted approach that considers the various environmental impacts of food trade.China is therefore encouraged to fully integrate the benefits of resource and environmental conservation into its sustainable food trade strategy,restructuring the food system to ensure the long-term nourishment of its large population. 展开更多
关键词 Food trade Virtual water Virtual land Virtual GHG emission Sustainable development assessment China
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Designing social immersive virtual environments for the Metaverse:The case study of MetaLibrary
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作者 Alberto CANNAVÒ Giorgio ARRIGO +2 位作者 Alessandro VISCONTI Federico De LORENZIS Fabrizio LAMBERTI 《虚拟现实与智能硬件(中英文)》 2025年第3期279-298,共20页
Background Over the last few years,the rapid advancement of technology has led to the development of many approaches to digitalization.In this respect,metaverse provides 3D persistent virtual environments that can be ... Background Over the last few years,the rapid advancement of technology has led to the development of many approaches to digitalization.In this respect,metaverse provides 3D persistent virtual environments that can be used to access digital content,meet virtually,and perform several professional and leisure tasks.Among the numerous technologies supporting the metaverse,immersive Virtual Reality(VR)plays a primary role and offers highly interactive social experiences.Despite growing interest in this area,there are no clear design guidelines for creating environments tailored to the metaverse.Methods This study seeks to advance research in this area by moving from state-of-the-art studies on the design of immersive virtual environments in the context of metaverse and proposing how to integrate cutting-edge technologies within this context.Specifically,the best practices were identified by i)analyzing literature studies focused on human behavior in immersive virtual environments,ii)extracting common features of existing social VR platforms,and iii)conducting interviews with experts in a specific application domain.Specifically,this study considered the creation of a new virtual environment for MetaLibrary,a VR-based social platform aimed at integrating public libraries into metaverse.Several implementation challenges and additional requirements have been identified for the development of virtual environments(VEs).These elements were considered in the selection of specific cutting-edge technologies and their integration into the development process.A user study was also conducted to investigate some design aspects(namely lighting conditions and richness of the scene layout)for which deriving clear indications from the above analysis was not possible because different alternative configurations could be chosen.Results The work reported in this paper seeks to bridge the gap between existing VR platforms and related literature in the field,on the one hand,and requirements regarding immersive virtual environments for the metaverse,on the other hand,by reporting a set of best practices which were used to build a social virtual environment that meets users'expectations and needs.Conclusions Results suggest that carefully designed virtual environments can positively affect user experience and interaction within metaverse.The insights gained from this study offer valuable cues for developing immersive virtual environments for the metaverse to deliver more effective and engaging experiences. 展开更多
关键词 Metaverse Design guidelines Virtual environments Immersive virtual reality User study Social platforms
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Peripheral NV-induced electron transfer to Fe1 single atoms for highly efficient O_(2)activation
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作者 Fenli Liu Man Yang +12 位作者 Jianglin Duan Zhiyu Yin Mingyang Shi Fuqing Chen Huifeng Xiong Xin Liu Wengang Liu Qixing Xia Shaodong Sun Dan Feng Haifeng Qi Yong Qin Yujing Ren 《Chinese Journal of Catalysis》 2025年第5期187-198,共12页
Catalytic oxidation plays a crucial role in chemical industry,in which the utilization of abundant and environmental-friendly oxygen(O_(2))as oxidant aligns with sustainable development principles in green chemistry.H... Catalytic oxidation plays a crucial role in chemical industry,in which the utilization of abundant and environmental-friendly oxygen(O_(2))as oxidant aligns with sustainable development principles in green chemistry.However,the intrinsic inertness of ground-state O_(2) molecule poses a long-standing challenge in developing an efficient non-noble metal-based catalyst.Herein,inspired by the electron transfer process in respiratory chain,we engineered long-range N_(V) to mediate Fe_(1) center for O_(2) activation in aerobic oxidation.Combined in/quasi-situ spectroscopic characterizations and control experiments suggest the Fe_(1) site efficiently adsorbs O_(2),and the N_(V) site facilitates electron delocalization to adjacent Fe_(1),providing efficient transformation of O_(2) to reactive oxygen species that boost oxidation reactions mildly.This Fe_(1)--N_(V) single-atom catalyst demonstrates outstanding catalytic performance in aerobic oxidations of alkanes,N-heterocycles,alcohols,and amines under relatively mild conditions.Our findings offer a new perspective for designing high-efficiency heterogeneous catalysts in aerobic oxidations,promising various potential applications. 展开更多
关键词 Single-atom catalyst Peripheral-nitrogen effect Long-range nv Synergistic catalysis Aerobic oxidation
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From Mimic Environment to Multiple Virtual Worlds: The Predicament and Breakage of News Reality in AIGC Era
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作者 Xi Wen 《Sociology Study》 2025年第6期286-293,共8页
From the era of mass communication to the era of generative artificial intelligence, under the construction of big data, algorithms and computing power, the mimicry environment has gradually evolved into multiple virt... From the era of mass communication to the era of generative artificial intelligence, under the construction of big data, algorithms and computing power, the mimicry environment has gradually evolved into multiple virtual dreamland: digital replication technology builds the first long-distance online news, and strong editing and weak mining aggravate the alienation of news production and practice;the algorithm model generated randomly by probability creates the second news illusion, and the exhaustibility of calculation makes AIGC completely divorced from reality. Man-machine speech cuts off the rational and open dialogue in the public sphere, and interpersonal relationship falls into the social division woven by man-machine relationship. In this process, the authenticity of news has suffered a fierce impact. From the perspective of the development history of media technology, based on the theory of “mimetic environment” put forward by Lippmann, taking ChatGPT as a concrete case, this paper reveals the current situation of the continuous separation between the public and the real and objective environment by analyzing the evolution logic from mimetic environment to multiple virtual worlds, and puts forward some ways to break the ice, such as collaboration between eyewitness evidence and intelligent technology, cooperation between generative AI and journalists, collusion between recommendation algorithm and value orientation, so as to seek an effective path to protect the truth of news and bridge the gap between the virtual and the real world. 展开更多
关键词 mimic environment virtual reality AIGC
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