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A frequency servo SoC with output power stabilization loop technology for miniaturized atomic clocks 被引量:1
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作者 Hongyang Zhang Xinlin Geng +3 位作者 Zonglin Ye Kailei Wang Qian Xie Zheng Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期13-22,共10页
A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic clocks.The proposed power stabilization loop(PSL... A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic clocks.The proposed power stabilization loop(PSL)technique,incorporating an off-chip power detector(PD),ensures that the output power of the FS-SoC remains stable,mitigating the impact of power fluctuations on the atomic clock's stability.Additionally,a one-pulse-per-second(1PPS)is employed to syn-chronize the clock with GPS.Fabricated using 65 nm CMOS technology,the measured phase noise of the FS-SoC stands at-69.5 dBc/Hz@100 Hz offset and-83.9 dBc/Hz@1 kHz offset,accompanied by a power dissipation of 19.7 mW.The Cs atomic clock employing the proposed FS-SoC and PSL obtains an Allan deviation of 1.7×10^(-11) with 1-s averaging time. 展开更多
关键词 CMOS technology atomic clock phase-locked loop output power stabilization 1PPS
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基于D-loop序列和微卫星标记的4个黄颡鱼群体的遗传变异分析
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作者 李兵部 傅建军 +2 位作者 陶易凡 强俊 徐跑 《黑龙江畜牧兽医》 CAS 北大核心 2024年第4期115-127,共13页
为探究广东珠江、广西漓江、四川金沙江和云南西江4个水系黄颡鱼(Pelteobagrus fulvidraco)群体的遗传变异情况,本研究分别基于上述水系共108尾黄颡鱼的线粒体D-loop序列和12个微卫星标记对4个黄颡鱼群体进行群体内遗传多样性、群体间... 为探究广东珠江、广西漓江、四川金沙江和云南西江4个水系黄颡鱼(Pelteobagrus fulvidraco)群体的遗传变异情况,本研究分别基于上述水系共108尾黄颡鱼的线粒体D-loop序列和12个微卫星标记对4个黄颡鱼群体进行群体内遗传多样性、群体间遗传距离和变异及群体结构分析。结果表明:共得到105个D-loop序列,其核苷酸组成中A+T含量占比为56.22%,G+C含量占比为43.78%。在105个有效序列中,多态位点数为746个(含缺和无效多态位点),单倍型数为51个。Hap2、Hap25、Hap15分别是广东珠江、广西漓江、四川金沙江群体的优势单倍型。4个黄颡鱼群体的单倍型多样性(H_(d))介于0.842~0.940,核苷酸多样性(π)介于0.002~0.083;四川金沙江群体Hd的最低,π也处于较低水平;而云南西江群体的Hd和π均最高;4个群体的Tajima′s D值均小于0。等位基因数(Na)、有效等位基因数(Ne)、观测杂合度(Ho)、期望杂合度(He)、多态信息含量(PIC)均为广西漓江群体最高,广东珠江群体次之,云南西江群体较低,四川金沙江群体最低。4个黄颡鱼群体的K2P遗传距离介于0.008~0.115之间,其中广西漓江与云南西江群体间的K2P遗传距离最近;广东珠江群体与其他3个群体的K2P遗传距离较远,与四川金沙江群体的K2P遗传距离最远。4个黄颡鱼群体间均存在极显著的遗传分化(P<0.01),群体间遗传分化指数(F_(st))介于0.114~0.959之间。4个黄颡鱼群体间Nei’s遗传距离和遗传一致性分别介于0.117~1.114之间和0.328~0.890之间,其中,广西漓江群体与云南西江群体的Nei’s遗传距离最近、遗传一致性最高,广东珠江与四川金沙江群体的Nei’s遗传距离最远、遗传一致性最低。在UPGMA系统聚类树中,4个黄颡鱼群体主要分为两支,其中广西漓江群体、云南西江群体最先聚为一支,然后与四川金沙江群体聚为一支,最后与广东珠江群体聚类。在NJ聚类树中,4个群体黄颡鱼的明显分为4个分支,广西漓江群体与云南西江群体呈镶嵌式分布。4个黄颡鱼群体中共享单倍型较少,但特有单倍型较多,其中云南西江和广西漓江群体相邻较近且共有单倍型较多。在基于Nei’s遗传距离进行的主坐标分析中,广西漓江群体和云南西江群体的个体之间遗传差异较小,广东珠江和四川金沙江群体的个体之间遗传差异较大。说明四川金沙江群体遗传多样性水平较低,云南西江群体遗传多样性水平较高,广西漓江群体与云南西江群体存在一定的基因交流。 展开更多
关键词 黄颡鱼 微卫星标记 D-loop序列 遗传多样性 群体结构
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庆阳驴mtDNA D-loop区遗传多样性及起源分析
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作者 施海娜 王永杰 +5 位作者 梁万鹏 耿智广 李世恩 徐振飞 刘刚 刘哲 《中国畜牧兽医》 CAS CSCD 北大核心 2024年第2期601-613,共13页
[目的]研究庆阳驴养殖群体的遗传多样性与母系起源,了解其遗传信息,为保护庆阳驴种质资源、选育和遗传改良工作提供理论依据。[方法]随机选取133头庆阳驴,对其线粒体DNA(mitochondrial DNA,mtDNA)D-loop区序列进行PCR扩增、测序及比对,... [目的]研究庆阳驴养殖群体的遗传多样性与母系起源,了解其遗传信息,为保护庆阳驴种质资源、选育和遗传改良工作提供理论依据。[方法]随机选取133头庆阳驴,对其线粒体DNA(mitochondrial DNA,mtDNA)D-loop区序列进行PCR扩增、测序及比对,并探讨庆阳驴的遗传多样性与母系起源。[结果]在获得的520 bp D-loop碱基序列中,AT含量(57.3%)高于GC含量(42.8%),表现出碱基的偏倚性;检测到38个变异位点,包含8个碱基对的转换;其核苷酸多样性(Pi)、单倍型多样性(Hd)、平均核苷酸差异(K)分别为0.01591、0.895和8.274,与欧洲家驴和中国家驴研究的平均值相比较低,说明该驴品种核苷酸变异较为贫乏。庆阳驴mtDNA D-loop区存在35个单倍型,单倍型之间的遗传距离为0.002~0.042。系统进化结果显示,庆阳驴存在2个线粒体支系,表明其具有2个母系起源,且遗传距离表明,庆阳驴与克罗地亚家驴之间的遗传距离较近。[结论]本研究从分子水平初步揭示庆阳驴核苷酸变异比较贫乏,杂交程度高,mtDNA遗传多态性正逐步丧失,应加强庆阳驴品种的遗传资源保护工作。 展开更多
关键词 庆阳驴 MTDNA D-loop 遗传多样性 起源
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基于线粒体Cyt b基因和D-loop区分析元江鲤和杞麓鲤群体遗传结构
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作者 张铭枭 赵玉姣 +6 位作者 姚创 刘霄 黄松茂 李红涛 代忠礼 武祥伟 孔令富 《水产学杂志》 CAS 2024年第3期13-21,共9页
本文利用线粒体Cyt b基因和D-loop区部分序列,分析元江鲤(Cyprinus carpio yuankiang)和杞麓鲤(Cyprinus carpio chilia)群体的遗传结构。结果表明,在两个鲤群体中均获得929 bp的Cyt b基因序列和650 bp的D-Loop区序列。两个群体间平均... 本文利用线粒体Cyt b基因和D-loop区部分序列,分析元江鲤(Cyprinus carpio yuankiang)和杞麓鲤(Cyprinus carpio chilia)群体的遗传结构。结果表明,在两个鲤群体中均获得929 bp的Cyt b基因序列和650 bp的D-Loop区序列。两个群体间平均遗传距离为0.00595(Cyt b)、0.00852(D-loop)。Cyt b基因共检测出元江鲤3种、杞麓鲤15种单倍型,两个群体共享两个单倍型(C-Hap1和C-Hap3);D-loop区序列共检测出元江鲤3种、杞麓鲤6种单倍型,两个群体共享两个单倍型(D-Hap1和D-Hap2)。元江鲤和杞麓鲤群体单倍型多样性(Hd)分别为0.30±0.10(Cyt b)、0.25±0.10(D-loop)和0.89±0.04(Cyt b)、0.73±0.05(D-loop)。元江鲤和杞麓鲤群体核苷酸多样性(π)分别为0.12±0.04(Cyt b)、0.12±0.09(D-loop)和0.77±0.09(Cyt b)、0.87±0.07(D-loop),杞麓鲤遗传多样性水平明显高于元江鲤群体。分子方差分析(AMOVA)显示,两个群体间有明显的遗传分化,且遗传变异主要来源于群体间。系统发育分析显示,元江鲤群体单倍型较少,类型较单一,与杞麓鲤群体差异大,多数元江鲤样本单倍型属于华南鲤(Cyprinus carpio rubrofuscus)类型;多数杞麓鲤样本具特有单倍型,部分属于华南鲤、远东鲤(Cyprinus carpio haematopterus)类型。结果表明,杞麓鲤与元江鲤群体遗传分化明显,元江鲤线粒体遗传多样性较低。 展开更多
关键词 元江鲤 杞麓鲤 Cyt b基因 D-loop 群体遗传结构 遗传多样性
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基于D-loop序列的从江田鱼与野生鲤形态和遗传差异分析
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作者 陆俊杰 何旭盟 +4 位作者 李志力 张宵 胡文静 孙佳敏 刘其根 《淡水渔业》 CSCD 北大核心 2024年第5期51-58,共8页
利用形态学测量方法和D-loop序列分析了解从江田鱼与都柳江野生鲤的形态和遗传差异分析。结果显示,体长/体宽特征存在极显著差异,野生鲤独有17个单倍型,其核苷酸多样性(Pi)和单倍型多样性(Hd)较从江田鱼更高。野生鲤与从江田鱼的Fst值... 利用形态学测量方法和D-loop序列分析了解从江田鱼与都柳江野生鲤的形态和遗传差异分析。结果显示,体长/体宽特征存在极显著差异,野生鲤独有17个单倍型,其核苷酸多样性(Pi)和单倍型多样性(Hd)较从江田鱼更高。野生鲤与从江田鱼的Fst值达到了0.15以上有较高的遗传分化。单倍型网络图显示,从江田鱼和野生鲤存在明显的遗传分化。分子方差(AMOVA)分析表明,从江田鱼群体的主要的遗传变异来自于群体内部个体间(80.66%)。基因流分析表明从江田鱼群体间基因交流水平不高但与野生鲤基因交流较频繁。研究表明,从江田鱼可能来源于野生鲤,其地理分布相对独立且有特定养殖模式,但受到自然和人工选择,其种群遗传多样性降低,种质资源存在退化风险需要保护。 展开更多
关键词 从江田鱼 线粒体D-loop 遗传多样性 遗传结构
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全镜下lasso-loop技术修复距腓前韧带治疗慢性踝关节不稳的疗效观察
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作者 刘松林 马亮 《生物骨科材料与临床研究》 CAS 2024年第5期51-53,58,共4页
目的 探讨采用lasso-loop技术治疗慢性踝关节不稳的临床疗效。方法 回顾性分析长江大学附属荆州医院2021年12月至2022年12月采用全镜下lasso-loop技术修复距腓前韧带手术的25例慢性踝关节不稳患者的临床资料。其中,男18例,女7例;年龄17... 目的 探讨采用lasso-loop技术治疗慢性踝关节不稳的临床疗效。方法 回顾性分析长江大学附属荆州医院2021年12月至2022年12月采用全镜下lasso-loop技术修复距腓前韧带手术的25例慢性踝关节不稳患者的临床资料。其中,男18例,女7例;年龄17~35岁,平均(25.12±1.27)岁;左踝10例,右踝15例。术后定期随访,记录并比较术前与末次随访时患者疼痛视觉模拟量表评分(visual analogue score, VAS)、美国骨科足踝协会踝-后足评分(American Orthopaedic Foot and Ankle Society, AOFAS)、Kaikkonen功能量表(Kaikkonen functional scale,KFS)。结果 25例患者均获得随访,随访时间平均为(11.08±0.86)个月。所有患者术后随访均未出现韧带修复失效,查体前抽屉试验及内翻应力试验均为(-)。末次随访时VAS评分[(1.28±0.23)分]较术前[(2.56±0.27)分]显著降低,AOFAS评分[(87.76±1.28)分]较术前[(46.56±2.36)分]明显上升,Kaikkonen踝关节损伤功能评分[(82.00±1.35)分]较术前[(41.80±2.78)分]明显上升,差异均有统计学意义(P<0.05)。结论 全镜下lasso-loop技术修复距腓前韧带是一种安全、有效的治疗慢性踝关节不稳的方法,近期疗效较好。 展开更多
关键词 关节镜 lasso-loop技术 距腓前韧带 慢性踝关节不稳
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建水黄褐鸭线粒体D-loop区遗传多样性分析
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作者 李昕鹏 展亚楠 +4 位作者 信爱国 黄艳 黄合特 张雪伟 孔小艳 《安徽农业科学》 CAS 2024年第2期83-86,共4页
[目的]了解建水黄褐鸭系统发育、遗传分化和遗传多样性。[方法]选取18只建水黄褐鸭、4只北京鸭、6只揭阳鸭和6只克里莫M18,利用PCR技术对其mtDNA D-loop区序列进行扩增,结合NCBI部分野鸭和家鸭序列,利用MEGA、DNAsp、Arlequin软件进行... [目的]了解建水黄褐鸭系统发育、遗传分化和遗传多样性。[方法]选取18只建水黄褐鸭、4只北京鸭、6只揭阳鸭和6只克里莫M18,利用PCR技术对其mtDNA D-loop区序列进行扩增,结合NCBI部分野鸭和家鸭序列,利用MEGA、DNAsp、Arlequin软件进行聚类分析、遗传分化和遗传多样性分析。[结果]建水黄褐鸭与绿头鸭及斑嘴鸭2种野鸭亲缘关系更近;遗传分化指数和遗传距离均以建水黄褐鸭和北京鸭之间最大;建水黄褐鸭、北京鸭、揭阳鸭和克里莫M18这4个群体中建水黄褐鸭群体遗传多样性最低。[结论]建水黄褐鸭可能有绿头鸭和斑嘴鸭2个母系起源;建水黄褐鸭群体遗传多样性偏低,为今后更好地利用地方畜禽资源,应采取相应措施保护其遗传多样性。 展开更多
关键词 建水黄褐鸭 D-loop 遗传分化 遗传距离 遗传多样性
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量子Loop代数U_(q)(L(sl_(2)))的单权模
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作者 吴青云 谭易兰 夏利猛 《吉林大学学报(理学版)》 CAS 北大核心 2024年第2期256-262,共7页
用构造的方法解决量子Loop代数U_(q)(L(sl_(2)))具有一个一维权空间的单权模的结构问题,得到了任意一个具有一维权空间的单权模必同构于U_(q)(L(sl_(2)))的四类单权模之一.此外,还构造了一类权空间维数为2的既非最高权也非最低权的量子L... 用构造的方法解决量子Loop代数U_(q)(L(sl_(2)))具有一个一维权空间的单权模的结构问题,得到了任意一个具有一维权空间的单权模必同构于U_(q)(L(sl_(2)))的四类单权模之一.此外,还构造了一类权空间维数为2的既非最高权也非最低权的量子Loop代数U_(q)(L(sl_(2)))的单权模. 展开更多
关键词 量子loop代数 权模 单模 Dense模
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Chemical looping reforming of the micromolecular component from biomass pyrolysis via Fe_(2)O_(3)@SBA-16
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作者 Yunchang Li Bo Zhang +3 位作者 Xiantan Yang Bolun Yang Shengyong Zhang Zhiqiang Wu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期120-134,共15页
To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling s... To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling strategy was adopted to decouple the biomass gasification process,and the composite oxygen carrier was prepared by embedding Fe_(2)O_(3) in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane,which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas.Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method,and the reforming performance was evaluated by a fixed bed reactor,and the kinetic parameters were solved based on the gas–solid reaction model.Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design.The experimental results showed that the reaction performance of Fe_(2)O_(3)@SBA-16 was compared with that of pure Fe_(2)O_(3) and Fe_(2)O_(3)@SBA-15,and the syngas yield was increased by 55.3%and 20.7%respectively,and it had good cycle stability.Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature.The activation energy was 192.79 kJ/mol by fitting.This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming. 展开更多
关键词 Biomass pyrolysis METHANE Chemical looping reforming Oxygen carrier Kinetic analysis
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Optimizing the sulfur-resistance and activity of perovskite oxygen carrier for chemical looping dry reforming of methane
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作者 Yuelun Li Dong Tian +6 位作者 Lei jiang Huicong Zuo LiNan Huang Mingyi Chen Jianchun Zuo Hua Wang Kongzhai Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期259-271,共13页
Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modu... Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modulate both the activity and resistance to sulfur poisoning by dual substitution of Mo and Ni ions with the Fe-sites of LaFeO_(3)perovskite.It is found that partial substitution of Ni for Fe substantially improves the activity of LaFeO_(3)perovskite,while Ni particles prefer to grow and react with H_(2)S during the long-term successive redox process,resulting in the deactivation of oxygen carriers.With the presence of Mo in LaNi_(0.05)Fe_(0.95)O_(3−σ)perovskite,H_(2)S preferentially reacts with Mo to generate MoS_(2),and then the CO_(2)oxidation can regenerate Mo via removing sulfur.In addition,Mo can inhibit the accumulation and growth of Ni,which helps to improve the redox stability of oxygen carriers.The LaNi_(0.05)Mo_(0.07)Fe_(0.88)O_(3−σ)oxygen carrier exhibits stable and excellent performance,with the CH_(4)conversion higher than 90%during the 50 redox cycles in the presence of 50 ppm H_(2)S at 800℃.This work highlights a synergistic effect in the perovskite oxides induced by dual substitution of different cations for the development of high-performance oxygen carriers with excellent sulfur tolerance. 展开更多
关键词 Perovskite oxygen carriers Chemical looping reforming Sulfur-resistance Dual substitution SYNGAS
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Advancing neuroscience through real-time processing of big data:Transition from open-loop to closed-loop paradigms
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作者 Yu-Fan Wang Jiu-Lin Du 《Zoological Research》 SCIE CSCD 2024年第3期518-519,共2页
The brain functions as a closed-loop system that continuously generates behavior in response to the external environment and adjusts actions based on the outcomes.Traditional research methodologies in neuroscience,esp... The brain functions as a closed-loop system that continuously generates behavior in response to the external environment and adjusts actions based on the outcomes.Traditional research methodologies in neuroscience,especially those employed in brain imaging experiments,have mainly adopted an open-loop paradigm(Grosenick et al.,2015).Functional neural circuits are analyzed offline and subsequently tested through manipulation of neuronal activities within specific regions or with genetic markers.By establishing a closed-loop research paradigm,functional ensembles can be detected and tested in real time with temporal sequences.These functional ensembles,rather than brain regions or genetically labeled neural populations,serve as fundamental units of neural networks,offering valuable insights into the dissection of neural circuits.The closed-loop research paradigm also enables the capture of high-dimensional activities of internal brain dynamics and precise elucidation of physiological processes such as learning,decision-making,and sleep. 展开更多
关键词 NEURAL loop TRANSITION
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Effects of interstitial cluster mobility on dislocation loops evolution under irradiation of austenitic steel
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作者 Xin‑Hua Yan Lu Sun +5 位作者 Du Zhou Teng Xie Chang Peng Ye‑Xin Yang Li Chen Zhen‑Feng Tong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期69-78,共10页
The evolution of dislocation loops in austenitic steels irradiated with Fe^(+)is investigated using cluster dynamics(CD)simulations by developing a CD model.The CD predictions are compared with experimental results in... The evolution of dislocation loops in austenitic steels irradiated with Fe^(+)is investigated using cluster dynamics(CD)simulations by developing a CD model.The CD predictions are compared with experimental results in the literature.The number density and average diameter of the dislocation loops obtained from the CD simulations are in good agreement with the experimental data obtained from transmission electron microscopy(TEM)observations of Fe~+-irradiated Solution Annealed 304,Cold Worked 316,and HR3 austenitic steels in the literature.The CD simulation results demonstrate that the diffusion of in-cascade interstitial clusters plays a major role in the dislocation loop density and dislocation loop growth;in particular,for the HR3 austenitic steel,the CD model has verified the effect of temperature on the density and size of the dislocation loops. 展开更多
关键词 Cluster dynamics Dislocation loops In-cascade interstitial clusters Austenitic steels
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Mn-doped SrCoO_(3-δ) Perovskite Oxides for Ethylene Production via Chemical Looping Oxidative Dehydrogenation of Ethane
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作者 Li Zhi Liu Linjiao +4 位作者 Hao Daijun Ren Xiaohang Shen Fangxia Li Xin Yu Anping 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期53-62,共10页
Chemical looping oxidative dehydrogenation (CL-ODH) is an economically promising method for convertingethane into higher value-added ethylene utilizing lattice oxygen in redox catalysts, also known as oxygen carriers.... Chemical looping oxidative dehydrogenation (CL-ODH) is an economically promising method for convertingethane into higher value-added ethylene utilizing lattice oxygen in redox catalysts, also known as oxygen carriers. Inthis study, perovskite-type oxide SrCoO_(3-δ) and B-site Mn ion-doped oxygen carriers (SrCo_(1-x)MnxO_(3-δ), x=0.1, 0.2, 0.3)were prepared and tested for the CL-ODH of ethane. The oxygen-deficient perovskite SrCoO_(3-δ) exhibited high ethyleneselectivity of up to 96.7% due to its unique oxygen vacancies and lattice oxygen migration rates. However, its low ethyleneyield limits its application in the CL-ODH of ethane. Mn doping promoted the reducibility of SrCoO_(3-δ) oxygen carriers,thereby improving ethane conversion and ethylene yield, as demonstrated by characterization and evaluation experiments.X-ray diffraction results confirmed the doping of Mn into the lattice of SrCoO_(3-δ), while X-ray photoelectron spectroscopy(XPS) indicated an increase in lattice oxygen ratio upon incorporation of Mn into the SrCoO_(3-δ) lattice. Additionally, H2temperature-programmed reduction (H2-TPR) tests revealed more peaks at lower temperature reduction zones and a declinein peak positions at higher temperatures. Among the four tested oxygen carriers, SrCo0.8Mn0.2O_(3-δ) exhibited satisfactoryperformance with an ethylene yield of 50% at 710 °C and good stability over 20 redox cycles. The synergistic effect of Mnplays a key role in increasing ethylene yields of SrCoO_(3-δ) oxygen carriers. Accordingly, SrCo0.8Mn0.2O_(3-δ) shows promisingpotential for the efficient production of ethylene from ethane via CL-ODH. 展开更多
关键词 ETHANE ETHYLENE PEROVSKITE chemical looping oxidative dehydrogenation
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Gigahertz frequency hopping in an optical phase-locked loop for Raman lasers
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作者 毛德凯 税鸿冕 +3 位作者 殷国玲 彭鹏 王春唯 周小计 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期60-65,共6页
Raman lasers are essential in atomic physics,and the development of portable devices has posed requirements for time-division multiplexing of Raman lasers.We demonstrate an innovative gigahertz frequency hopping appro... Raman lasers are essential in atomic physics,and the development of portable devices has posed requirements for time-division multiplexing of Raman lasers.We demonstrate an innovative gigahertz frequency hopping approach of a slave Raman laser within an optical phase-locked loop(OPLL),which finds practical application in an atomic gravimeter,where the OPLL frequently switches between near-resonance lasers and significantly detuned Raman lasers.The method merges the advantages of rapid and extensive frequency hopping with the OPLL’s inherent low phase noise,and exhibits a versatile range of applications in compact laser systems,promising advancements in portable instruments. 展开更多
关键词 Raman lasers optical phase-locked loop frequency hopping
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Rapid and stable calcium-looping solar thermochemical energy storage via co-doping binary sulfate and Al–Mn–Fe oxides
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作者 Changjian Yuan Xianglei Liu +8 位作者 Xinrui Wang Chao Song Hangbin Zheng Cheng Tian Ke Gao Nan Sun Zhixing Jiang Yimin Xuan Yulong Ding 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1290-1305,共16页
Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffe... Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffer from slow reaction kinetics,poor stability,and low solar absorptance.Here,we successfully realized high power density and highly stable solar thermochemical energy storage/release by synergistically accelerating energy storage/release via binary sulfate and promoting cycle stability,mechanical strength,and solar absorptance via Al–Mn–Fe oxides.The energy storage density of proposed CaCO_(3)pellets is still as high as 1455 kJ kg^(-1)with only a slight decay rate of 4.91%over 100 cycles,which is higher than that of state-of-the-art pellets in the literature,in stark contrast to 69.9%of pure CaCO_(3)pellets over 35 cycles.Compared with pure CaCO_(3),the energy storage power density or decomposition rate is improved by 120%due to lower activation energy and promotion of Ca^(2+)diffusion by binary sulfate.The energy release or carbonation rate rises by 10%because of high O^(2-)transport ability of molten binary sulfate.Benefiting from fast energy storage/release rate and high solar absorptance,thermochemical energy storage efficiency is enhanced by more than 50%under direct solar irradiation.This work paves the way for application of direct solar thermochemical energy storage techniques via achieving fast energy storage/release rate,high energy density,good cyclic stability,and high solar absorptance simultaneously. 展开更多
关键词 Calcium looping(CaL) Solar thermochemical Energy storage Binary sulfate Fast reaction kinetics
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Ethane Chemical Looping Oxidative Dehydrogenation to Ethylene over Co_(2)O_(3)(Fe_(2)O_(3),NiO)/LaCoO_(3) Oxygen Carriers
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作者 Liang Hao Meng Jinhong +1 位作者 Sun Jie Wei Dongkai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期33-41,共9页
Ethane chemical looping oxidative dehydrogenation(CL-ODH)to ethylene is a new technology for converting ethane to ethylene.In the current study MeO/LaCoO_(3)(MeO=Fe_(2)O_(3),NiO or Co_(2)O_(3))composite metal oxides w... Ethane chemical looping oxidative dehydrogenation(CL-ODH)to ethylene is a new technology for converting ethane to ethylene.In the current study MeO/LaCoO_(3)(MeO=Fe_(2)O_(3),NiO or Co_(2)O_(3))composite metal oxides were prepared via citrate gel and impregnation methods,and used as oxygen carriers for CL-ODH.X-ray diffraction results indicated that all oxygen carriers had a perovskite structure even after eight redox cycles.Under a reaction temperature of 650°C,a reaction pressure of 0.1 MPa,and a weight hourly space velocity(WHSV)of 7500 mL/(g·h),ethane conversion over Co_(2)O_(3)/LaCoO_(3) reached 100%and ethylene selectivity reached 60%,both of which were better than corresponding values attained over Fe_(2)O_(3)/LaCoO_(3) and NiO/LaCoO_(3).Ethylene selectivity remained stable for 80 cycles over Co_(2)O_(3)/LaCoO_(3),then decreased gradually after 80 cycles.X-ray photoelectron spectroscopy results and evaluation results indicated that lattice oxygen and O_(2)2-had a direct relationship with ethane conversion and ethylene selectivity.Co_(2)O_(3)/LaCoO_(3) exhibited a strong capacity to release and absorb oxygen,mainly due to interaction between Co_(2)O_(3) and LaCoO_(3). 展开更多
关键词 chemical looping oxidative dehydrogenation ETHANE ETHYLENE oxygen carrier PEROVSKITE
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Multitap RF Canceller with Single LMS Loop for Adaptive Co-Site Broadband Interference Cancellation
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作者 Jiang Yunhao Liu Zhipeng +4 位作者 Yuan Lei Xu Anfei Wang Hang Zhao Nan Wu Minghu 《China Communications》 SCIE CSCD 2024年第9期179-197,共19页
With the development of wireless communication technology,an urgent problem to be solved is co-site broadband interference on independent communication platforms such as satellites,space stations,aircrafts and ships.A... With the development of wireless communication technology,an urgent problem to be solved is co-site broadband interference on independent communication platforms such as satellites,space stations,aircrafts and ships.Also,the problem of strong selfinterference rejection should be solved in the co-time co-frequency full duplex mode which realizes spectrum multiplication in 5G communication technology.In the research of such interference rejection,interference cancellation technology has been applied.In order to reject multipath interference,multitap double LMS(Least Mean Square)loop interference cancellation system is often used for cancelling RF(Radio Frequency)domain interference cancelling.However,more taps will lead to a more complex structure of the cancellation system.A novel tap single LMS loop adaptive interference cancellation system was proposed to improve the system compactness and reduce the cost.In addition,a mathematical model was built for the proposed cancellation system,the correlation function of CP2FSK(Continuous Phase Binary Frequency Shift Keying)signal was derived,and the quantitative relationship was established between the correlation function and the interference signal bandwidth and tap delay differential.The steadystate weights and the expression of the average interference cancellation ratio(ICR)were deduced in the scenes of LOS(Line of Sight)interference with antenna swaying on an independent communication platform and indoor multipath interference.The quantitative relationship was deeply analyzed between the interference cancellation performance and the parameters such as antenna swing,LMS loop gain,and interference signal bandwidth,which was verified by simulation experiment.And the performance of the proposed interference cancellation system was compared with that of the traditional double LMS loop cancellation system.The results showed that the compact single LMS loop cancellation system can achieve an average interference rejection capability comparable to the double LMS loop cancellation system. 展开更多
关键词 co-site broadband interference delay matching RF interference cancellation single LMS loop
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CO_(2)capture costs of chemical looping combustion of biomass:A comparison of natural and synthetic oxygen carrier
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作者 Benjamin Fleiß Juraj Priscak +3 位作者 Martin Hammerschmid Josef Fuchs Stefan Müller Hermann Hofbauer 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期296-310,共15页
Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and ... Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology. 展开更多
关键词 Chemical looping combustion BECCS Techno-economic assessment CO_(2)capture costs Oxygen carrier development Synthetic materials ILMENITE
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Generalized nth-Order Perturbation Method Based on Loop Subdivision Surface Boundary Element Method for Three-Dimensional Broadband Structural Acoustic Uncertainty Analysis
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作者 Ruijin Huo Qingxiang Pei +1 位作者 Xiaohui Yuan Yanming Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期2053-2077,共25页
In this paper,a generalized nth-order perturbation method based on the isogeometric boundary element method is proposed for the uncertainty analysis of broadband structural acoustic scattering problems.The Burton-Mill... In this paper,a generalized nth-order perturbation method based on the isogeometric boundary element method is proposed for the uncertainty analysis of broadband structural acoustic scattering problems.The Burton-Miller method is employed to solve the problem of non-unique solutions that may be encountered in the external acoustic field,and the nth-order discretization formulation of the boundary integral equation is derived.In addition,the computation of loop subdivision surfaces and the subdivision rules are introduced.In order to confirm the effectiveness of the algorithm,the computed results are contrasted and analyzed with the results under Monte Carlo simulations(MCs)through several numerical examples. 展开更多
关键词 Perturbation method loop subdivision surface isogeometric boundary element method uncertainty analysis
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Unraveling the atomic interdiffusion mechanism of NiFe_(2_)O_(4)oxygen carriers during chemical looping CO_(2)conversion
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作者 Da Song Yan Lin +8 位作者 Shiwen Fang Yang Li Kun Zhao Xinfei Chen Zhen Huang Fang He Zengli Zhao Hongyu Huang Fanxing Li 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期105-121,共17页
By employing metal oxides as oxygen carriers,chemical looping demonstrates its effectiveness in transferring oxygen between reduction and oxidation environments to partially oxidize fuels into syngas and convert CO_(2... By employing metal oxides as oxygen carriers,chemical looping demonstrates its effectiveness in transferring oxygen between reduction and oxidation environments to partially oxidize fuels into syngas and convert CO_(2)into CO.Generally,NiFe_(2_)O_(4)oxygen carriers have demonstrated remarkable efficiency in chemical looping CO_(2)conversion.Nevertheless,the intricate process of atomic migration and evolution within the internal structure of bimetallic oxygen carriers during continuous high‐temperature redox cycling remains unclear.Consequently,the lack of a fundamental understanding of the complex ionic migration and oxygen transfer associated with energy conversion processes hampers the design of high‐performance oxygen carriers.Thus,in this study,we employed in situ characterization techniques and theoretical calculations to investigate the ion migration behavior and structural evolution in the bulk of NiFe_(2_)O_(4)oxygen carriers during H2 reduction and CO_(2)/lab air oxidation cycles.We discovered that during the H2 reduction step,lattice oxygen rapidly migrates to vacancy layers to replenish consumed active oxygen species,while Ni leaches from the material and migrates to the surface.During the CO_(2)splitting step,Ni migrates toward the core of the bimetallic oxygen carrier,forming Fe–Ni alloys.During the air oxidation step,Fe–Ni migrates outward,creating a hollow structure owing to the Kirkendall effect triggered by the swift transfer of lattice oxygen.The metal atom migration paths depend on the oxygen transfer rates.These discoveries highlight the significance of regulating the release–recovery rate of lattice oxygen to uphold the structures and reactivity of oxygen carriers.This work offers a comprehensive understanding of the oxidation/reduction‐driven atomic interdiffusion behavior of bimetallic oxygen carriers. 展开更多
关键词 chemical looping CO_(2)splitting density functional theory in situ characterization ionic migration
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