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In-situ deposited anti-aging TiN capping layer for Nb superconducting quantum circuits

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CHINESE PHYSICS B 2024年第9期33卷 133-137页

作者： Tao, Hao-Ran Du, Lei guo, Liang-Liang Chen, Yong Zhang, Hai-Feng Yang, Xiao-Yan Xu, guo-Liang Zhang, Chi jia, Zhi-Long Duan, Peng guo, guo-Ping Univ Sci & Technol China CAS Key Lab Quantum Informat Hefei 230026 Peoples R China Univ Sci & Technol China CAS Ctr Excellence Synerget Innovat Ctr Quantum Informat & Quantum Ph Hefei 230026 Peoples R China Origin quantum Comp Co Ltd Hefei 230088 Peoples R China

The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal-air interface, where Nb2O5 is considered the main loss source. Here, we suppress the formation of native oxides by in-situ deposition of a TiN capping layer on the Nb film. With TiN capping layers, no Nb2O5 forms on the surface of the Nb film. The quality factor q(i) of the Nb resonator increases from 5.6 x 10(5) to 7.9 x 10(5) at low input power and from 6.8 x 10(6) to 1.1 x 10(7) at high input power. Furthermore, the TiN capping layer also shows good aging resistance in Nb resonator devices, with no significant performance fluctuations after one month of aging. These findings highlight the effectiveness of TiN capping layers in enhancing the performance and longevity of Nb superconducting quantum devices.

关键词： anti-aging oxidation dielectric loss Nb superconducting quantum circuits NIOBIUM

A new approach to quantifying vehicle induced turbulence for complex traffic scenarios

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Chinese Journal of Chemical Engineering 2016年第1期24卷 71-78页

作者： Yesul Kim Li Huang Sunling gong Charles q.jia Department of Chemical Engineering and Applied Chemistry University of Toronto200 College Street Toronto ON MSS 3E5 Canada Air quality Research Division Environment CanadaTorontoON M3H 5T4 Canada

Traffic-related pollutants adversely affect air quality, especially in regions near major roadways. The vehicleinduced turbulence(VIT) is a significant factor that controls the initial dilution, dispersion, and ultimately the chemical and physical fate of pollutants by altering the conditions in the microenvironment. This study used a computational fluid dynamics(CFD) software FLUENT to model the vehicle-induced turbulence(VIT) generated on roadways, with a focus on impact of vehicle-vehicle interactions, traffic density and vehicle composition on turbulent kinetic energy(TKE). We show, for the first time, that the overall TKE from multiple vehicles traveling in series can be estimated by superimposing the TKE of each vehicle, without considering the distance between them while the distance is greater than one vehicle length. This finding is particularly significant since it enables a new approach to VIT simulations where the overall TKE is calculated as a function of number of vehicles. We found that the interactions between vehicles traveling next to each other in adjacent lanes are insignificant,regardless the directions of the traffic flow. Consequently, simulations of different traffic scenarios can be substantially simplified by treating two-way traffic as one-way traffic, with less than 5% difference in the overall volume-averaged TKE. We also developed equations that allow the estimation of the overall volume-averaged TKE as a function of the number and the type of vehicles.

关键词： Computational fluid dynamics Turbulent kinetic energy Vehicle-induced turbulence Road-induced turbulence Mixed traffic

内蒙古自治区中西部Lg波衰减及场地响应特征研究

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地震 2024年第1期44卷 109-117页

作者：贾昕晔白少奇贾彦杰刘芳娜热内蒙古自治区锡林浩特地震监测中心站内蒙古锡林浩特027000 内蒙古自治区地震局内蒙古呼和浩特010010

基于Lg波谱比与台站场地响应联合反演的方法,选取2016-2020年内蒙古自治区及邻区地震台网记录到的ML≥2.8地震事件78次,开展内蒙古自治区中西部地震波衰减和场地响应分析研究。结果显示,三分向衰减参数分别为q_(UD)(f)=372·f^(0.54),q_... 详细信息

基于Lg波谱比与台站场地响应联合反演的方法,选取2016-2020年内蒙古自治区及邻区地震台网记录到的ML≥2.8地震事件78次,开展内蒙古自治区中西部地震波衰减和场地响应分析研究。结果显示,三分向衰减参数分别为q_(UD)(f)=372·f^(0.54),q_(EW)(f)=287·f^(0.59),q_(NS)(f)=382·f^(0.43)。分析34个台站场地响应可得,EKH、 BYT、 HYS台站在1~7 Hz频段内有明显放大效应,BHS、 XLT、 RLT台站在1~3 Hz频段有明显放大效应,可能与台站所处复杂的地质构造有关。

关键词：内蒙古自治区中西部 Lg波衰减参数场地响应

Approximations for a queueing game Model with Join-the-Shortest-queue Strategy

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Journal of the Operations Research Society of China 2023年第3期11卷 489-504页

作者： qi-Hui Bu Li-Wei Liu jia-Shan Tang Yi-qiang q.Zhao School of Science Nanjing University of Posts and TelecommunicationsNanjing210023JiangsuChina School of Science Nanjing University of Science and TechnologyNanjing210094JiangsuChina School of Mathematics and Statistics Carleton UniversityOttawaONK1S 5B6Canada

This paper investigates a partially observable queueing system with N nodes in which each node has a dedicated arrival *** is an extra arrival stream to balance the load of the system by routing its customers to the shortest *** addition,a reward-cost structure is considered to analyse customers'strategic *** equilibrium and socially optimal strategies are derived for the partially observable mean field limit ***,we show that the strategies obtained from the mean field model are good approximations to the model with finite N ***,numerical experiments are provided to compare the equilibrium and socially optimal behaviours,including joining probabilities and social benefits for different system parameters.

关键词： game theory queueing systems Mean field limit Markov process

IL-6/JAK2/STAT3信号通路在电针调控胰岛素抵抗模型大鼠骨代谢中的作用

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中华骨质疏松和骨矿盐疾病杂志 2024年第4期17卷 336-343页

作者：周广文张家瑶张麟李佳贺雯陈丽湖北中医药大学针灸骨伤学院武汉430065 武汉市中西医结合医院/武汉市第一医院骨关节科武汉430022 武汉理工大学医院康复科武汉430070

目的研究电针对胰岛素抵抗(insulin resistance,IR)大鼠骨代谢及炎症状态的影响。方法8只大鼠按照随机数字表单列为空白组,另外32只大鼠给予高脂饲料喂养8周以建立IR大鼠模型,选取造模成功的24只大鼠,随机分为模型组、假电针组、电针组... 详细信息

目的研究电针对胰岛素抵抗(insulin resistance,IR)大鼠骨代谢及炎症状态的影响。方法8只大鼠按照随机数字表单列为空白组,另外32只大鼠给予高脂饲料喂养8周以建立IR大鼠模型,选取造模成功的24只大鼠,随机分为模型组、假电针组、电针组,每组8只,空白组、假电针组不做干预,电针组选取“中脘”“关元”、“足三里”、“丰隆”4穴进行电针治疗,假电针组选取上述4穴旁边的皮下后不进行电针治疗,各组均治疗8周。在治疗前后,测量各组大鼠的体质量(body mass,BM)、空腹血糖(fasting blood-glucose,FBg)及餐后血糖水平(postprandial blood-glucoser,PBg)、葡萄糖输注速率(glucose infusion rate,gIR);各组大鼠血清中Ⅰ型胶原氨基端前肽(N-terminal propeptide of typeⅠcollagen,P1NP)、β-Ⅰ型胶原C末端肽(C-terminal telopeptides of typeⅠcollagen,β-CTX)含量用酶联免疫吸附测定(enzyme-linked immunosorbent assay,ELISA)检测;大鼠骨组织的骨密度(bone mineral density,BMD)、骨体积分数(BV/TV)、骨小梁数量(trabecularNumber,Tb.N)和骨小梁分离度(trabecularSeparation/Spacing,***)采用微计算机断层扫描技术(micro CT)检测;骨组织中白细胞介素-6(interleukin-6,IL-6)、Janus蛋白酪氨酸激酶2(Janus Protein Tyrosine Kinase2,JAK2)、信号转导与转录活化因子3(Signal Transducers and Activators of Transcription 3,STAT3)mRNA及蛋白的表达分别采用实时荧光定量聚合酶链式反应(Real-time PCR)与蛋白免疫印迹法(Western blot)检测。结果治疗前与空白组相比,模型组、假电针组、电针组大鼠BMD、PBg值明显升高(PgIR明显降低(Pg、PBg、β-CTX、IL-6、JAK2、STAT3 mRNA及蛋白浓度明显升高(PgIR、P1NP、BMD、BV/TV、Tb.N和***明显降低(Pg、β-CTX、IL-6、JAK2、STAT3 mRNA及蛋白浓度均明显降低,BMD、BV/TV、Tb.N、***、gIR均明显升高(Pg、JAK2 mRNA、STAT3蛋白表达明显降低(P0.05)。结论电针能够通过调控IL-6/JAK2/STAT3信号通路降低机体炎症反应改善胰岛素抵抗,并能一定程度的降低机体破骨细胞活性,减少骨吸收。

关键词：白细胞介素-6 Janus蛋白酪氨酸激酶2 信号转导与转录活化因子3 IL-6/JAK2/STAT3信号通路胰岛素抵抗

Alkali-thermal gasification and hydrogen generation potential of biomass

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 369-378页

作者： Alexander B. Koven Shitang S. Tong Ramin R. Farnood Charles q. jia Department of Chemical Engineering and Applied Chemistry University of Toronto Ontario M5S-3E5 Canada School of Chemistry and Chemical Engineering Wuhan University of Science and Technology Wuhan 430081 China

generating hydrogen gas from biomass is one approach to lowering dependencies on fossil fuels for energy and chemical feedstock, as well as reducing greenhouse gas emissions. Using both equilibrium simulations and batch experiments with NaOH as a model alkaline, this study established the technical feasibility of converting various biomasses （e.g., glucose, cellulose, xylan and lignin） into H2-rich gas via catalyst-free, alkali-thermal gasification at moderate temperatures （as low as 300℃）. This process could produce more H2 with less carbon-containing gases in the product than other comparable methods. It was shown that alkali-thermal gasification follows CxHyO2 ＋ 2xNaOH ＋（x-z）H20 = （2x＋y/2-z）H2 ＋xNa2CO3, with carbonate being the solid product which is different from the one suggested in the literature. Moreover, the concept of hydrogen genera- tion potential （H2-gP）-the maximum amount of H2 that a biomass can yield, was introduced. For a given biomass CxHyO2, the H2-gP would be （2x ＋ y/2-z） moles of H2. It was demonstrated experimentally that the H2-gP was achievable by adjusting the amounts of H20 and NaOH, temperature and pressure. Keywords hydrogen generation potential, biomass, lignocellulose, alkali-thermal gasification, sodium hydroxide

关键词： hydrogen generation potential biomass lignocellulose alkali-thermal gasification sodium hydroxide

SAR激励信号正交调制幅相不平衡预失真校正方法

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中国科学院大学学报（中英文） 2024年第4期41卷 524-532页

作者：贾颖新王岩飞中国科学院空天信息创新研究院北京100190 中国科学院大学北京100049

模拟正交调制技术是合成孔径雷达(SAR)宽带激励信号产生中最常用也是最重要的技术手段之一,随着雷达系统瞬时带宽越来越大,模拟正交调制的Iq一致性特性无法仅依靠器件的对称特性来保证,而Iq不平衡在宽带雷达发射系统中带来的杂散失真会... 详细信息

模拟正交调制技术是合成孔径雷达(SAR)宽带激励信号产生中最常用也是最重要的技术手段之一,随着雷达系统瞬时带宽越来越大,模拟正交调制的Iq一致性特性无法仅依靠器件的对称特性来保证,而Iq不平衡在宽带雷达发射系统中带来的杂散失真会随着链路逐级恶化。针对上述情况,提出一种数字预失真补偿方法,通过对整个发射通道进行系统误差建模并搭建测试系统,能够提取包含正交调制Iq不平衡在内的整个发射链路上的所有幅相误差,并将幅相误差映射到数字基带信号输出的Iq支路上,通过数字预失真的方式补偿发射通道的幅相失真,使得输出的雷达激励信号具有接近理想的幅相特性。最后结合实际的雷达发射系统,利用预失真算法对整个发射链路进行失真校正,给出校正前后的测试对比结果,通过测试表明方法的有效性。

关键词：合成孔径雷达正交调制宽带 Iq不平衡幅相误差

Drosophila homolog of the intellectual disability-related long-chain acyl-CoA synthetase 4 is required for neuroblast proliferation

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Journal of genetics and genomics 2019年第1期46卷 5-17页

作者： Mingyue jia Danqing Meng Mo Chen Tingting Li Yong q.Zhang Aiyu Yao State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences University of Chinese Academy of Sciences

Mutations in long-chain acyl-CoA synthetase 4 (ACSL4) are associated with non-syndromic X-linked intellectual disability (ID). However, the neural functions of ACSL4 and how loss of ACSL4 leads to ID remain largely unexplored. We report here that mutations in Acsl, the Drosophila ortholog of human ACSL3 and ACSL4, result in developmental defects of the mushroom body (MB), the center of olfactory learning and memory. Specifically, Acsl mutants show fewer MB neuroblasts (Nbs) due to reduced proliferation activity and premature differentiation. Consistently, these surviving Nbs show reduced expression of cyclin E, a key regulator of the g1-to S-phase cell cycle transition, and nuclear mislocalization of the transcriptional factor Prospero, which is known to repress self-renewal genes and activate differentiating genes. Furthermore, RNA-seq analysis reveals downregulated Nb-and cell-cyclerelated genes and upregulated neuronal differentiation genes in Acsl mutant Nbs. As Drosophila Acsl and human ACSL4 are functionally conserved, our findings provide novel insights into a critical and previously unappreciated role of Acsl in neurogenesis and the pathogenesis of ACSL4-related ID.

关键词： ACSL4 Drosophila Mushroom body Neuroblast Neural stem cell Premature differentiation

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面向非完全电磁信息的智能频谱分配技术研究

电子与信息学报 2024年第7期46卷 2694-2702页

作者：赵浩钦段国栋司江勃黄睿石嘉西安电子科技大学通信工程学院西安710071 中国电子科技集团公司第二十九研究所成都610036

针对电磁对抗过程中环境动态变化,多节点自主用频决策频谱利用率低的问题,该文开展面向非完全电磁信息的智能协同频谱分配技术研究,通过多节点智能协同提升频谱利用率。首先将复杂电磁环境频谱分配问题建模为最大化用频设备的优化问题,... 详细信息

针对电磁对抗过程中环境动态变化,多节点自主用频决策频谱利用率低的问题,该文开展面向非完全电磁信息的智能协同频谱分配技术研究,通过多节点智能协同提升频谱利用率。首先将复杂电磁环境频谱分配问题建模为最大化用频设备的优化问题,其次提出一种基于多节点协同分流经验回放机制的资源决策算法(CoDDqN),算法基于协同分流函数对历史经验数据进行评估,并通过分级经验池进行训练,使各智能体在仅观测自身状态信息条件下形成轻量级协同决策能力,解决低视度条件下多节点决策优化方向与整体优化目标不一致的问题,提升频谱利用率;设计了一种基于置信分配的混合奖励函数,各节点决策兼顾个体的奖励,能够减少惰性节点的出现,探索更优的整体动作策略,进一步提升系统效益。仿真结果表明:当节点数为20时,所提算法的可接入设备数优于全局贪婪算法与遗传算法,并与信息完全共享的集中式频谱分配算法的差距在5%内,更适用于低视度节点的协同频谱分配。

关键词：频谱资源分配深度强化学习非完全电磁信息协同分流机制

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