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The origin and evolution of Earth's nitrogen

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National Science Review 2024年第6期11卷 56-75页

作者： Yuan li State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Bayerisches Geoinstitut Universit?t Bayreuth

Nitrogen is a vital element for life on Earth. Its cycling between the surface(atmosphere + crust) and the mantle has a profound influence on the atmosphere and climate. However, our understanding of the origin and evolution of Earth's nitrogen is still incomplete. This review presents an overview of the current understanding of Earth's nitrogen budget and the isotope composition of different reservoirs, laboratory constraints on deep nitrogen geochemistry, and our understanding of the origin of Earth's nitrogen and the deep nitrogen cycle through plate subduction and volcanism. The Earth may have acquired its nitrogen heterogeneously during the main accretion phase, initially from reduced, enstatite-chondrite-like impactors,and subsequently from increasingly oxidized impactors and minimal CI-chondrite-like materials. like Earth's surface, the mantle and core are also significant nitrogen reservoirs. The nitrogen abundance and isotope composition of these three reservoirs may have been fundamentally established during the main accretion phase and have been insignificantly modified afterwards by the deep nitrogen cycle, although there is a net nitrogen ingassing into Earth's mantle in modern subduction zones. However, it is estimated that the early atmosphere of Earth may have contained ～1.4 times the present-day atmospheric nitrogen(PAN),with ～0.4 PAN being sequestered into the crust via biotic nitrogen fixation. In order to gain a better understanding of the origin and evolution of Earth's nitrogen, directions for future research are suggested.

关键词： nitrogen isotopes silicate Earth atmosphere magma ocean

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西葫芦品种的株型研究及评价

西北农业学报 2010年第11期19卷 104-109页

作者：雷逢进温祥珍李亚灵武惠玲李燕李晓琦山西省农业科学院棉花研究所山西运城044000 山西农业大学园艺学院山西太谷030801

通过主成分和聚类分析研究了10个西葫芦品种的株型结构,并对其进行了评价,旨在探讨日光温室西葫芦株型结构与产量的关系。结果表明,14个株型性状中差异达显著水平和变异系数达10%共8个性状;主成分分析表明前2个主分量累计达到90.26%,第... 详细信息

通过主成分和聚类分析研究了10个西葫芦品种的株型结构,并对其进行了评价,旨在探讨日光温室西葫芦株型结构与产量的关系。结果表明,14个株型性状中差异达显著水平和变异系数达10%共8个性状;主成分分析表明前2个主分量累计达到90.26%,第一主分量为蔓性、叶片特征因子,贡献率达73.96%,第二主分量为叶片倾角因子,贡献率达16.30%,二维排序表明品种东葫4号(S5)和东葫5号(S7)两个因子的协调性最好,其株型通风透光较好;聚类分析类平均距离D=0.733 7,依据株高和茎节把参试品种分为2大类:矮蔓和半矮蔓株型,类平均距离D=0.622 3,依据叶片倾角和叶面积分为4个亚类株型;二维排序和聚类分析结果的趋势相同;相关分析表明,产量与第一主分量得分达显著正相关(r=0.962 4*),说明株型结构诸因子中株高、茎节长以及叶面积和功能叶片数是影响产量的主要形态因子;以产量对2类4亚类株型进行评价,表明适宜日光温室西葫芦长季节栽培的株型第一是半矮蔓大叶紧凑型,其次是半矮蔓大叶松散型,矮蔓株型可用于日光温室抢早上市栽培。

关键词：西葫芦主成分聚类分析产量

A fast and high-accurate commutation failure identification method for LCC-HVDC system

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High Voltage 2024年第3期9卷 721-732页

作者： Jing Feng Zhijie liu Kejun li Bingkun li Jiachen li liangzi li School of Electrical Engineering Shandong UniversityJinanShandongChina

Commutation failure(CF)is one of the most common issues in line-commuted converter-based high voltage direct current systems(LCC-HVDC),leading to critical power system security and stability *** and rapid identification of CF is crucial to prevent subsequent CF in HVDC ***,the existing CF identi-fication methods are lack of the required accuracy and *** relationship between bridge arm current,commutation voltage,and trigger pulse based on the commutation progress mechanism after the AC fault is analysed in this paper.A novel CF identification method is presented,which utilises the CF identification factor,enabling fast and high-accurate identification without relying on the value of the extinction *** pro-posed method offers a simpler and more efficient implementation in engineering ***,the effectiveness of the proposed method is verified in both the standard In-ternational Council on Large Electric systems HVDC model and the Hardware in Loop test using practical project *** results demonstrate that the proposed method can accurately and fast identify CF.

关键词： system method LCC

Heralded entanglement between error-protected logical qubits for fault-tolerant distributed quantum computing

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 25-33页

作者： Jialun li Zhihao Xie Yachen li Yansen liang Zhenhua li Tao li MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing School of PhysicsNanjing University of Science and TechnologyNanjing 210094China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China

Quantum error correction is essential for achieving reliable quantum information processing tasks,as it can mitigate the detrimental effects of noise by encoding single-qubit information into a larger quantum ***,the generation of distributed entanglement between logical qubits located within two spatially separated nodes presents a significant resource-intensive challenge that has yet to be *** we present a heralded protocol for generating distributed entanglement between two nonlocal error-protected logical qubits.A high-dimensional single photon can evolve physical qubits into a logical qubit that entangles with the photon and then converts logical qubit-photon entanglement into entanglement between two logical qubits,when the photon state is properly tuned and an effective photon-spin interface between single photons and individual spins is ***,the success of the entanglement generation is heralded by the detection of the photon,and the corresponding efficiency can,in principle,approach *** distinguished features make our protocol highly appealing for future large-scale quantum technologies.

关键词： quantum networks distributed entanglement error-protected logical qubits high-dimensional photons

禽网状内皮组织增殖病病毒gp90蛋白单克隆抗体的制备及其识别区分析

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生物工程学报 2015年第1期31卷 75-85页

作者：孙明铭李晓齐曹红王永强郑世军中国农业大学动物医学院农业生物技术国家重点实验室北京100193

为了制备禽网状内皮组织增殖病病毒(REV)gp90蛋白的单克隆抗体,应用His-gp90融合蛋白免疫BALB/c小鼠,取免疫鼠的脾细胞与骨髓瘤细胞(SP2/0)进行融合,经过筛选、3次亚克隆后获得3株稳定分泌抗REV-gp90蛋白的单克隆抗体杂交瘤细胞株,分别... 详细信息

为了制备禽网状内皮组织增殖病病毒(REV)gp90蛋白的单克隆抗体,应用His-gp90融合蛋白免疫BALB/c小鼠,取免疫鼠的脾细胞与骨髓瘤细胞(SP2/0)进行融合,经过筛选、3次亚克隆后获得3株稳定分泌抗REV-gp90蛋白的单克隆抗体杂交瘤细胞株,分别命名为3G5-B8、3G5-A10和1G12。经间接EliSA(Enzyme-linked immunosorbent assay)方法检测,单克隆抗体的亲和力解离常数(Kd)分别为6.483×10–10、4.844×10–10和9.330×10–10,3株单抗的亚型分别为Ig G1、Ig G1和Ig G2b。经Western blotting和间接免疫荧光实验检测,3株单抗均能识别REV感染DF-1细胞后产生的gp90蛋白。以Western blotting方法利用单抗检测不同截短的gp90蛋白,初步确定3G5-B8和3G5-A10 2株单抗抗原识别区均位于gp90蛋白第200-245位氨基酸,而1G12株单抗识别区包含第230-235位氨基酸。这些单抗为REV的诊断和致病机理研究奠定了基础。

关键词：禽网状内皮组织增殖病病毒 gp90蛋白单克隆抗体亲和力抗原表位

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智能网联汽车Wi-Fi隐私泄露风险研究

西安电子科技大学学报 2023年第4期50卷 215-228页

作者：杨波钟永超杨浩男徐紫枫李晓琦张玉清海南大学网络空间安全学院海南海口570208 中国科学院大学国家计算机网络入侵防范中心北京101408

针对智能网联汽车隐私泄露风险评估中不完整、主观性强、难以量化损失的问题,提出了一种定性和定量结合的隐私风险评估模型。首先在定性风险评估模型的基础上,提出了新的隐私分类,扩展了现有标准的隐私影响评级;其次,设计了一种基于Wi-F... 详细信息

针对智能网联汽车隐私泄露风险评估中不完整、主观性强、难以量化损失的问题,提出了一种定性和定量结合的隐私风险评估模型。首先在定性风险评估模型的基础上,提出了新的隐私分类,扩展了现有标准的隐私影响评级;其次,设计了一种基于Wi-Fi的隐私泄露检测方案,解决定量评估中的数据收集问题;最后,对泄露的隐私数据从信息熵、影响等级、个人身份信息类型等多因素进行综合价值度量,引入隐私数据定价模型量化攻击收益,将攻击收益和概率的乘积作为预估损失值。通过3辆智能网联汽车的真车实验,证明了该隐私泄露检测方案的可行性。对隐私数据的定性和定量风险评估表明,扩展的影响评级、隐私度量和定价模型优于现有方案,有效量化了智能网联汽车的隐私泄露风险,定量转换的风险值与定性评估的风险值具有良好的一致性。

关键词：智能网联汽车 Wi-Fi 隐私泄露风险评估 ISO标准

基于AlexNet卷积神经网络的大米产地高光谱快速判别

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中国食品学报 2022年第1期22卷 282-288页

作者：吴静珠李晓琪林珑刘翠玲刘志袁玉伟北京工商大学食品安全大数据技术北京市重点实验室北京100048 浙江省农业科学院农业部农产品信息溯源重点实验室杭州310021

采集我国东北和非东北10个产地、4个品种共计1000份单粒大米样本在波长950~1700 nm区间的高光谱图像,按照单粒大米轮廓提取感兴趣区域并计算平均光谱,采用主成分分析从样本集光谱矩阵提取累计贡献率大于99%的第一、二主成分,根据载荷矩... 详细信息

采集我国东北和非东北10个产地、4个品种共计1000份单粒大米样本在波长950~1700 nm区间的高光谱图像,按照单粒大米轮廓提取感兴趣区域并计算平均光谱,采用主成分分析从样本集光谱矩阵提取累计贡献率大于99%的第一、二主成分,根据载荷矩阵系数最大值筛选与第一、二主成分相关性最强的特征波长1396.67 nm和1467.38 nm。针对两组特征波长图像进行主成分分析,分别选取前三维主成分,共计可得2×3组训练样本集。结果表明:基于AlexNet卷积神经网络训练建立6组东北/非东北大米产地高光谱快速判别模型,均有较高的识别准确率,其中基于1467.38 nm波长的第三主成分图像建立的东北/非东北大米产地判别模型的性能最佳,其识别准确率可达99.5%。

关键词：高光谱大米产地鉴别主成分分析 AlexNet卷积神经网络

传染性法氏囊病病毒VP4蛋白单克隆抗体的制备及鉴定

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生物工程学报 2014年第11期30卷 1660-1668页

作者：柳亚楠李夏莹李忠华王永强李晓齐曹红郑世军中国农业大学动物医学院农业生物技术国家重点实验室北京100193

传染性法氏囊病病毒(IBDV)蛋白VP4在抑制宿主免疫应答中起重要作用,为制备IBDV VP4的单克隆抗体,以实验室保存的融合蛋白His-VP4免疫BALB/c小鼠,经过细胞融合、筛选、亚克隆后获得4株能稳定分泌抗VP4的单抗杂交瘤细胞株,分别命名为3B3、... 详细信息

传染性法氏囊病病毒(IBDV)蛋白VP4在抑制宿主免疫应答中起重要作用,为制备IBDV VP4的单克隆抗体,以实验室保存的融合蛋白His-VP4免疫BALB/c小鼠,经过细胞融合、筛选、亚克隆后获得4株能稳定分泌抗VP4的单抗杂交瘤细胞株,分别命名为3B3、3H11、4C8和4G6,经间接EliSA测定4株单抗的亲和力解离常数分别为4.61×10–11、1.71×10–10、4.26×10–11和5.02×10–11,均为高亲和力抗体。4株单抗的重链类型分别为Ig G1、Ig G1、Ig G2b和Ig G1。进一步以Western blotting鉴定,该4株单抗均能特异地识别IBDV的VP4蛋白,间接免疫荧光和Western blotting试验表明4株单抗均能识别IBDV感染DF-1细胞后产生的VP4蛋白。该单抗为检测IBDV以及研究IBDV VP4的生物学作用奠定了基础。

关键词：传染性法氏囊病病毒 VP4蛋白原核表达单克隆抗体

An internal ballistic model of electromagnetic railgun based on PFN coupled with multi-physical field and experimental validation

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Defence Technology（防务技术） 2024年第2期32卷 254-261页

作者： Benfeng Gu Haiyuan li Baoming li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094China

To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore *** this paper,a three-dimensional numerical model of the augmented railgun with four parallel unconventional rails is introduced to simulate the internal ballistic process and realize the multi-physics field coupling calculation of the rail gun,and a test experiment of a medium-caliber electromagnetic launcher powered by pulse formation network(PFN)is carried *** test methods such as spectrometer,fiber grating and high-speed camera are used to test several parameters such as muzzle initial velocity,transient magnetic field strength and stress-strain of *** the simulation results and experimental data,the damage condition of the contact surface is analyzed.

关键词： Internal ballistic modeling Electromagnetic rail gun Multi-physics field coupling Experimental validation PFN