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太赫兹低频段粗糙目标的表面散射及成像特性研究

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激光与光电子学进展 2024年第10期61卷 158-166页

作者：柴鑫悦胡浩胡晓雪马欣茹席思星王晓雷南开大学电子信息与光学工程学院现代光学研究所天津300350 河北工程大学数理科学与工程学院河北邯郸056038

目标表面散射特性是利用太赫兹波进行雷达成像、目标识别和定位的物理基础,而影响目标表面散射特性的因素主要是目标材料和表面粗糙度。以金属铝材料为例,基于0.1 THz频点处的Drude模型参数拟合结果,利用基尔霍夫近似(KA)法分析了高斯... 详细信息

目标表面散射特性是利用太赫兹波进行雷达成像、目标识别和定位的物理基础,而影响目标表面散射特性的因素主要是目标材料和表面粗糙度。以金属铝材料为例,基于0.1 THz频点处的Drude模型参数拟合结果,利用基尔霍夫近似(KA)法分析了高斯型随机粗糙铝表面的散射系数。对蒙特卡罗(Monte-Carlo)粗糙目标的雷达散射截面(RCS)进行仿真分析,实现了二维逆合成孔径雷达(ISAR)成像。研究结果表明:目标RCS仿真结果与KA理论分析结果相符,即在小俯仰角下表面粗糙度与RCS呈负相关,而在大俯仰角下表面粗糙度与RCS呈正相关。此外,在一定的粗糙范围内,随着表面粗糙度的增加,目标表面的散射中心增多,在ISAR图像上形成密集的“斑点状”效果,更能反映目标的形状和结构。

关键词：粗糙面散射低频太赫兹波散射系数基尔霍夫近似雷达散射截面逆合成孔径雷达成像

Carrier-driven magnetic and topological phase transitions in twodimensional III-V semiconductors

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Nano Research 2023年第2期16卷 3443-3450页

作者： Yan Li xinru ma Hongwei Bao Jian Zhou Fei ma Jingbo Li State Key Laboratory for Mechanical Behavior of materials Xi’an Jiaotong UniversityXi’an 710049China Center for Alloy Innovation and Design Xi’an Jiaotong UniversityXi’an 710049China Institute of Semiconductors South China Normal UniversityGuangzhou 510631China

III-V semiconductors such as GaAs are widely studied as promising candidates for high-speed integrated *** these applications for conventional bulk structures,their fundamental physical properties in the nanoscale limit are still in scarcity,which is of great importance for the development of *** this work,we demonstrate that the III-V semiconductor MX(M=Al,Ga,In;X=P,As,Sb)in its two-dimensional(2D)limit could exhibit double layer honeycomb(DLHC)configuration and distorted tetrahedral coordination,according to our first-principles calculations with HSE06 hybrid *** is found that surface reconstruction endows 2D III-V DLHCs with pronouncedly different electronic and magnetic properties from their bulk counterparts due to strong interlayer ***-hat-shape bands emerge at the top valence bands of pristine AlP,GaP,InP,AlAs,and InAs DLHCs,inducing the density of states showing a sharp van Hove singularity near the Fermi *** a result,these DLHCs exhibit itinerant magnetism upon moderate hole doping,while the rest GaAs,AlSb,GaSb,and InSb DLHCs become magnetic under tensile strain with hole *** an exchange splitting of the localized pz states at the top valence bands,the hole-doped III-V DLHCs become half-metals with 100%***,the InSb DLHC shows inverted band structure near the Fermi level,bringing about nontrivial topological band structures in stacked InSb DLHC due to the strong spin-orbital *** III-V DLHCs expand the members of 2D material family and their exotic magnetic and topological properties may offer great potential for applications in the novel electronic and spintronic devices.

关键词： III-V semiconductors HSE06 hybrid functional Mexican-hat-shape bands magnetism topological bands

金水宝片联合异丙托溴铵治疗慢性支气管炎的临床研究

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现代药物与临床 2024年第6期39卷 1500-1504页

作者：王立红吕秀云宿利清张松马馨茹王慧内蒙古医科大学附属医院呼吸与危重症医学科内蒙古呼和浩特010050

目的探讨金水宝片联合异丙托溴铵治疗慢性支气管炎的临床疗效。方法选取2021年1月—2023年11月内蒙古医科大学附属医院收治的慢性支气管炎患者106例,随机分为对照组(53例)和治疗组(53例)。对照组雾化吸入吸入用异丙托溴铵溶液,2 mL/... 详细信息

目的探讨金水宝片联合异丙托溴铵治疗慢性支气管炎的临床疗效。方法选取2021年1月—2023年11月内蒙古医科大学附属医院收治的慢性支气管炎患者106例,随机分为对照组(53例)和治疗组(53例)。对照组雾化吸入吸入用异丙托溴铵溶液,2 mL/次,2次/d。在此基础上,治疗组口服金水宝片,4片/次,3次/d。两组患者治疗3个月。观察两组患者临床疗效,比较治疗前后两组患者主症消失时间,肺功能指标用力肺活量(FVC)、呼气峰值流量(PEF)和最大呼气中段流量(MMEF)水平,外周血T淋巴细胞亚群水平,及血清嗜酸性粒细胞趋化因子(Eotaxin)、肿瘤坏死因子-α(TNF-α)、转化生长因子-β1(TGF-β1)和内皮素-1(ET-1)水平。结果治疗后,治疗组临床总有效率为96.23%,明显高于对照组的84.91%(P<0.05)。治疗后,治疗组各项主症的消失时间均明显短于对照组(P<0.05)。治疗后,两组患者FVC、PEF、MMEF、CD3^(+)、CD4^(+)和CD4^(+)/CD8^(+)水平明显高于治疗前,而CD8^(+)、Eotaxin、TNF-α、TGF-β1和ET-1水平显著低于治疗前(P<0.05),且治疗后治疗组患者肺功能指标、外周血T淋巴细胞亚群水平和血清因子水平明显好于对照组(P<0.05)。结论金水宝片联合异丙托溴铵治疗慢性支气管炎可加速患者症状缓解,提高肺功能及临床疗效,改善免疫功能及炎症状态。

关键词：金水宝片吸入用异丙托溴铵溶液慢性支气管炎用力肺活量呼气峰值流量最大呼气中段流量 T淋巴细胞亚群嗜酸性粒细胞趋化因子内皮素-1

低氧环境紫锥菊提取物-菊苣酸通过PPAR信号通路对SD大鼠肝脏组织脂肪合成的影响

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中国兽医学报 2024年第1期44卷 135-140页

作者：行倩文吴华刘嘉华刘波张龙飞陈鑫磊马欣茹青海大学农牧学院青海西宁810016

为探究紫锥菊提取物-菊苣酸在低氧环境下影响SD大鼠肝脏脂肪代谢的分子机制。选取60只健康雄性SD大鼠(6~8周龄,(192±7.35)g)(P>0.05),适应性喂养2周后,随机分为对照组、不同浓度CA组(10、20、40 mg/kg),每组15只,连续灌胃49 d。4组大... 详细信息

为探究紫锥菊提取物-菊苣酸在低氧环境下影响SD大鼠肝脏脂肪代谢的分子机制。选取60只健康雄性SD大鼠(6~8周龄,(192±7.35)g)(P>0.05),适应性喂养2周后,随机分为对照组、不同浓度CA组(10、20、40 mg/kg),每组15只,连续灌胃49 d。4组大鼠均自由采食和饮水,灌胃第50天对SD大鼠进行麻醉处理后,采集肝脏组织,并通过油红O染色法计算各组大鼠肝脏组织油滴面积占总面积的百分比以及测定PPAR信号通路关键因子PLIN2、PLIN5、PPARα、PPARγ、RXRα的表达情况。油红O染色结果显示:与对照组相比,添加紫锥菊提取物-菊苣酸组极显著降低油红O染色面积(P<0.01);PPAR信号通路关键因子表达结果显示:与对照组相比,添加紫锥菊提取物-菊苣酸组显著降低PLIN2、PLIN5、PPARα、PPARγ、RXRα的mRNA及蛋白表达量(P<0.05),其中以添加10 mg/kg紫锥菊提取物-菊苣酸组对PLIN2、PLIN5、PPARα、PPARγ、RXRα的mRNA及蛋白表达量效果最显著(P<0.05)。结果表明,紫锥菊提取物-菊苣酸降低脂肪合成相关因子的表达,调控脂肪的合成与储存,预防脂肪的过多累积导致机体脂质代谢紊乱,紫锥菊提取物-菊苣酸改善了低氧诱导的脂质代谢功能障碍,且10 mg/kg组作用效果最好。本研究为紫锥菊提取物-菊苣酸作为高海拔地区预防高原动物脂质代谢紊乱的饲料添加剂的开发利用提供了理论基础。

关键词：低氧菊苣酸 SD大鼠肝脏组织油红O PPAR信号通路脂肪合成

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闪烁体光束准直光学系统设计

现代应用物理 2024年第2期15卷 42-51页

作者：马欣茹胡浩胡晓雪王晓雷南开大学电子信息与光学工程学院现代光学研究所天津市微尺度光学信息技术科学重点实验室天津300350 强脉冲辐射环境模拟与效应全国重点实验室西安710024

为更好地实现对闪烁光的高效率收集和高质量准直,提升探测效果,便于进行后续的闪烁体光束控制或偏转等实验,分别提出了同轴光束准直系统和离轴光束准直系统,设计优化了该系统中的自由曲面透镜、二次曲面反射镜等器件的参数。采用光学软... 详细信息

为更好地实现对闪烁光的高效率收集和高质量准直,提升探测效果,便于进行后续的闪烁体光束控制或偏转等实验,分别提出了同轴光束准直系统和离轴光束准直系统,设计优化了该系统中的自由曲面透镜、二次曲面反射镜等器件的参数。采用光学软件LightTools对闪烁体光束准直系统进行仿真。结果表明:所设计的同轴光束准直系统和离轴光束准直系统均能有效地实现对闪烁光的准直,其中自由曲面透镜离轴反射镜系统将光束发散角从±40°压缩为±5°,光能利用率可达96%以上,光束角内光能利用率达83%以上,实现了对光束传播方向的调控,提高了闪烁光的收集效率。

关键词：闪烁体发散角光收集效率自由曲面透镜二次曲面反射镜光学准直系统

Head-to-head comparison of PSma PET/CT and mpMRI for detecting biochemical recurrence of prostate cancer: A systematic review and meta-analysis

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Current Urology 2024年第3期18卷 177-184页

作者： xinru Zhang Zhe ma Department of Ultrasound The First Affiliated Hospital of Shandong First Medical UniversityJinanChina

Objectives This study aimed to evaluate the performance of prostate-specific membrane antigen positron emission tomography/computed tomography(PSma PET/CT)in comparison to multiparametric magnetic resonance imaging(mpMRI)for detecting biochemical recurrence of prostate cancer(PCa).materials and methods We conducted a comprehensive search for articles published in PubMed,Web of Science,Embase,and the Cochrane Library,spanning the inception of the database until October 26,2022,which included head-to-head comparisons of PSma PET/CT and mpMRI for assessing the biochemical recurrence of *** A total of 5 studies including 228 patients were *** overall positivity rates of PSma PET/CT and mpMRI for detecting biochemical recurrence of PCa after final treatment were 0.68(95%confidence interval[CI],0.52–0.89)and 0.56(95%CI,0.36–0.88),*** positivity rates of PSma PET/CT and mpMRI for detecting local recurrence,lymph node metastasis,and bone metastases were 0.37(95%CI,0.30–0.47)and 0.38(95%CI,0.22–0.67),0.44(95%CI,0.35–0.56)and 0.25(95%CI,0.17–0.35),and 0.19(95%CI,0.11–0.31)and 0.12(95%CI,0.05–0.25),*** with mpMRI,PSma PET/CT exhibited a higher positivity rate for detecting biochemical recurrence and lymph node metastases,and no significant difference in the positivity rate of local recurrence was observed between these 2 imaging *** Compared with mpMRI,PSma PET/CT appears to have a higher positivity rate for detecting biochemical recurrence of *** both imaging methods showed similar positivity rates of detecting local recurrence,PSma PET/CT outperformed PSma PET/CT in detecting lymph node involvement and overall recurrence.

关键词： Prostate-specific membrane antigen Positron emission tomography/computed tomography Multiparametric magnetic resonance imaging Prostate cancer Biochemical recurrence Positive rate

Effects of Different Chinese Hickory Husk Returning Modes on Soil Nutrition and Microbial Community in Acid Forest Soil

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Phyton-International Journal of Experimental Botany 2023年第3期92卷 943-954页

作者： Qian Liu Sayikal Duyxanale Yongqian Tang Xinyu Shen Yuanlai Zhao xinru ma Shuai Shao Chenfei Liang State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou311300China Lingfeng Temple Forest Farm Anji313300China

Chinese hickory(Carya cathayensis Sarg.)is an important economic forest in Southeastern China.A large amount of hickory husk waste is generated every year but with a low proportion of ***,intensive management has resulted in soil degradation of Chinese hickory *** study aims to investigate the effects of three Chinese hickory husk returning modes on soil amendment,including soil acidity,soil nutrition,and microbial *** field experiment carried out four treatments:control(CK),hickory husk mulching(HM),hickory husk biochar(BC),and hickory husk organic fertilizer(OF).The phospholipid fatty acid(PLFA)biomarker method was employed to determine the soil microbial *** one year of treatment,the results showed that:(i)HM and BC significantly increased soil pH by 0.33 and 1.71 units,respectively;(ii)HM,BC and OF treatments significantly increased the soil organic carbon,alkaline nitrogen,available phosphorous,and available *** OF treatment demonstrated the most significant improvement in the soil nutrient;(iii)The soil microbial biomass significantly increased in the HM,BC and OF treatments,and all microbial groups showed an increasing *** treatment increased the fungal/bacterial ratio(F/B).The OF treatment significantly decreased the Shannon-Wiener diversity(H’)and evenness index(J)of the microbial community(Pmanure.

关键词： Chinese hickory husk organic fertilizer biochar mulching phospholipid fatty acids soil microbial community

A Dual-Cluster-Head Based Medium Access Control for Large-Scale UAV Ad-Hoc Networks

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China Communications 2024年第5期21卷 123-136页

作者： Zhao xinru Wei Zhiqing Zou Yingying ma Hao Cui Yanpeng Feng Zhiyong Key Laboratory of Universal Wireless Communications Ministry of EducationSchool of Information and Communication EngineeringBeijing University of Posts and TelecommunicationsBeijing100876China

Unmanned Aerial Vehicle(UAV)ad hoc network has achieved significant growth for its flexibility,extensibility,and high deployability in recent *** application of clustering scheme for UAV ad hoc network is imperative to enhance the performance of throughput and energy *** conventional clustering scheme,a single cluster head(CH)is always assigned in each ***,this method has some weaknesses such as overload and premature death of CH when the number of UAVs *** order to solve this problem,we propose a dual-cluster-head based medium access control(DCHmaC)scheme for large-scale UAV *** DCHmaC,two CHs are elected to manage resource allocation and data forwarding ***,two CHs work on different *** of CH is used for intra-cluster communication and the other one is for inter-cluster communication.A markov chain model is developed to analyse the throughput of the *** result shows that compared with FM-maC(flying ad hoc networks multi-channel maC,FM-maC),DCHmaC improves the throughput by approximately 20%~50%and prolongs the network lifetime by approximately 40%.

关键词： dual cluster head medium access control UAV swarm

A Note on Finitely Generated Modules over a <i>PID</i>

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Advances in Pure mathematics 2020年第12期10卷 699-705页

作者： xinru ma Heguo Liu Honglian Zhang Department of mathematics Shanghai University Shanghai China School of mathematics and Statistics Hubei University Wuhan China

In this note, we provide an effective proof of the fundamental structure theorem of finitely generated modules over a principal ideal domain, from which we find the minimality of decomposition for a finitely generated... 详细信息

关键词： Finitely Generated Module Principal Ideal Domain Cyclic Module