Miniature tunable Airy beam optical meta-device

Tunable Airy beams with controllable propagation trajectories have sparked interest in various fields,such as optical manipulation and laser fabrication.Existing research approaches encounter challenges related to insufficient compactness and integration feasibility,or they require enhanced tunability to enable real-time dynamic manipulation of the propagation trajectory.In this work,we present a novel method that utilizes a dual metasurface system to surpass these limitations,significantly enhancing the practical potential of the Airy beam.Our approach involves encoding a cubic phase profile and two off-axis Fresnel lens phase profiles across the two metasurfaces.The validity of the proposed strategy has been confirmed through simulation and experimental results.The proposed meta-device addresses the existing limitations and lays the foundation for broadening the applicability of Airy beams across diverse domains,encompassing light-sheet microscopy,laser fabrication,optical tweezers,etc.

Light-based 3D printing of stimulus-responsive hydrogels forminiature devices:recent progress and perspective

Miniature devices comprising stimulus-responsive hydrogels with high environmental adaptability are now considered competitive candidates in the fields of biomedicine,precise sensors,and tunable optics.Reliable and advanced fabricationmethods are critical formaximizing the application capabilities ofminiature devices.Light-based three-dimensional(3D)printing technology offers the advantages of a wide range of applicable materials,high processing accuracy,and strong 3D fabrication capability,which is suitable for the development of miniature devices with various functions.This paper summarizes and highlights the recent advances in light-based 3D-printed miniaturized devices,with a focus on the latest breakthroughs in lightbased fabrication technologies,smart stimulus-responsive hydrogels,and tunable miniature devices for the fields of miniature cargo manipulation,targeted drug and cell delivery,active scaffolds,environmental sensing,and optical imaging.Finally,the challenges in the transition of tunable miniaturized devices from the laboratory to practical engineering applications are presented.Future opportunities that will promote the development of tunable microdevices are elaborated,contributing to their improved understanding of these miniature devices and further realizing their practical applications in various fields.

Preliminary study of metabonomic changes during the progression of atherosclerosis in miniature pigs

Background:To explore potential biomarkers for early diagnosis of atherosclerosis(AS)and provide basic data for further research on AS,the characteristics of serum metabolomics during the progression of AS in mini-pigs were observed dynamically.Methods:An AS model in Bama miniature pigs was established by a high-cholesterol and high-fat diet.Fasting serum samples were collected monthly for metabolomics and serum lipid detection.At the end of the treatment period,pathological analysis of the abdominal aorta and coronary artery was performed to evaluate the lesions of AS,thereby distinguishing the susceptibility of mini-pigs to AS.The metabolomics was de-tected using a high-resolution untargeted metabolomic approach.Statistical analysis was used to identify metabolites associated with AS susceptibility.Results:Based on pathological analysis,mini-pigs were divided into two groups:a susceptible group(n=3)and a non-susceptible group(n=6).A total of 1318 metabo-lites were identified,with significant shifting of metabolic profiles over time in both groups.Dynamic monitoring analysis highlighted 57 metabolites that exhibited an ob-vious trend of differential changes between two groups with the advance of time.The KEGG(Kyoto Encyclopedia of Genes and Genomes)pathway enrichment analysis in-dicated significant disorders in cholesterol metabolism,primary bile acid metabolism,histidine metabolism,as well as taurine and hypotaurine metabolism.Conclusions:During the progression of AS in mini-pigs induced by high-cholesterol/high-fat diet,the alterations in serum metabolic profile exhibited a time-dependent pattern,accompanied by notable disturbances in lipid metabolism,cholesterol me-tabolism,and amino acid metabolism.These metabolites may become potential bio-markers for early diagnosis of AS.

Online pharmaceutical process analysis of Chinese medicine using a miniature mass spectrometer: Extraction of active ingredients as an example

The automation of traditional Chinese medicine(TCM)pharmaceuticals has driven the development of process analysis from offline to online.Most of common online process analytical technologies are based on spectroscopy,making the identification and quantification of specific ingredients still a challenge.Herein,we developed a quality control(QC)system for monitoring TCM pharmaceuticals based on paper spray ionization miniature mass spectrometry(mini-MS).It enabled real-time online qualitative and quantitative detection of target ingredients in herbal extracts using mini-MS without chromatographic separation for the first time.Dynamic changes of alkaloids in Aconiti Lateralis Radix Praeparata(Fuzi)during decoction were used as examples,and the scientific principle of Fuzi compatibility was also investigated.Finally,the system was verified to work stably at the hourly level for pilot-scale extraction.This mini-MS based online analytical system is expected to be further developed for QC applications in a wider range of pharmaceutical processes.

Whole-genome sequencing study to identify candidate markers indicating susceptibility to type 2 diabetes in Bama miniature pigs

Background:Hundreds of single-nucleotide polymorphism(SNP)sites have been found to be potential genetic markers of type 2 diabetes mellitus(T2DM).However,SNPs related to T2DM in minipigs have been less reported.This study aimed to screen the T2DM-susceptible candidate SNP loci in Bama minipigs so as to improve the success rate of the minipig T2DM model.Methods:The genomic DNAs of three Bama minipigs with T2DM,six sibling lowsusceptibility minipigs with T2DM,and three normal control minipigs were compared by whole-genome sequencing.The T2DM Bama minipig-specific loci were obtained,and their functions were annotated.Meanwhile,the Biomart software was used to perform homology alignment with T2DM-related loci obtained from the human genome-wide association study to screen candidate SNP markers for T2DM in Bama miniature pigs.Results:Whole-genome resequencing detected 6960 specific loci in the minipigs with T2DM,and 13 loci corresponding to 9 diabetes-related genes were selected.Further,a set of 122 specific loci in 69 orthologous genes of human T2DM candidate genes were obtained in the pigs.Collectively,a batch of T2DM-susceptible candidate SNP markers in Bama minipigs,covering 16 genes and 135 loci,was established.Conclusions:Whole-genome sequencing and comparative genomics analysis of the orthologous genes in pigs that corresponded to the human T2DM-related variant loci successfully screened out T2DM-susceptible candidate markers in Bama miniature pigs.Using these loci to predict the susceptibility of the pigs before constructing an animal model of T2DM may help to establish an ideal animal model.

空射诱饵弹对地面防空装备作战使用影响研究

空射诱饵弹(miniature air launched decoy,MALD)可诱骗地面防空雷达开机,消耗防空弹药,降低地面防空装备作战效能,提升空中编队突防能力。在梳理空射诱饵弹发展概况基础上,分析空射诱饵弹目标特性,构建典型作战运用场景,开展MALD对制导雷达探测跟踪性能和拦截效能影响分析,采用理论分析和动态仿真的方法研究了空射诱饵弹实施远距离欺骗、抵近干扰对制导雷达探测跟踪性能的影响,采用排队论方法分析MALD对空中编队突防效能的影响。研究结论可为空射诱饵弹战术运用提供参考。

VHF频段小型化千瓦级GaN功率放大器

为了满足VHF频段对高功率放大器小型化的需求,设计并制备了一款基于05μm GaN高电子迁移率晶体管(HEMT)工艺的VHF频段小型化千瓦级功率放大器。通过采用多节微带电容网络和高介电常数的印制电路板(PCB)实现了末级功率放大器匹配电路的小型化;以高通滤波器作为级间匹配电路,在减小电路尺寸的同时,提高了链路增益;采用混合集成工艺,实现了电源调制器、前级驱动功率放大器和末级功率放大器等各单元的小型化高密度集成。测试结果表明,在024~030 GHz频带内,该功率放大器的工作电压为50 V,工作脉宽为100μs,在占空比10%、输入功率10 dBm的工作条件下,带内输出功率大于1000 W,功率附加效率约为60%~69%,功率增益大于50 dB,功放体积为46 mm×30 mm×6 mm。

岩土离心模型试验软接触式微型土压计研制及性能评价

微型土压计是岩土离心模型试验的重要测量技术之一。为解决刚性土压计测量中拱效应、尺寸效应、厚径比等经典误差问题及提升频响速率和精度,尝试开发了一种全新软接触式微型土压计ESP-II,介绍了其技术创新和设计方法。以两种国际代表性土压计为参考,设计开展一系列离心模型试验,对其感应精度、速率和适用性进行评价。主要结论:①逐级加载离心加速度5g~50g试验下,各深度ESP-II和两种参考传感器测试结果与理论值的平均误差分别为5.16%,6.70%,4.85%,三者沿深度拟合K_(0)优度系数R^(2)均≥0.9893。②脉冲荷载试验中ESP-II最大响应时间约7.8 ms,略优于两种参考传感器,具有良好的频响速率。③不同幅值正弦、地震等动荷载试验下,3种传感器测得土压力均呈一致增量趋势,K_(0)约由0.43~0.45增至0.51~0.56,与既有规律认识吻合。④离心机下降卸荷过程中,ESP-II测得时程表现良好连续性和光滑性,反映软接触式设计有利于保障土体与传感器良好接触和稳定响应。研究成果,初步证明了软接触式土压计适应于静、动力离心试验需求,具有重要价值与应用前景。

小型猪气管插管时异氟醚半数有效剂量的探索

目的本研究拟探讨小剂量舒泰(1.5 mg/kg)肌注复合异氟烷吸入用于保留自主呼吸的小型猪气管插管时50%和95%有效的异氟烷最小肺泡气浓度(50%and 95%minimum alveolar concentrations effective inhaled,MAC EI50and MAC EI95),为小型猪提供安全的麻醉插管方法。方法44例全身麻醉的巴马小型猪,肌注舒泰镇静后,面罩吸入异氟烷进行麻醉诱导,监测心率、血压、呼吸、体温、氧饱和度、呼末二氧化碳浓度和呼末异氟烷浓度。初始呼末异氟烷浓度设置为2.0%,采用Cooper’s评分评价气管插管满意度,采用Dixon’s改良序贯法测算剂量-效应关系。Probit回归法计算MAC EI50和MAC EI95及95%可信区间(confidence interval,CI)。结果小剂量舒泰复合异氟烷吸入诱导直接喉镜气管插管时,小型猪肺泡气浓度的MAC EI503.10%(95%CI 2.79%~3.56%),MAC EI953.77%(95%CI 3.41%~6.42%);在做好监测和气道管理预案的基础上,肺泡异氟烷浓度3.10%~3.75%,均能保证小型猪生命体征稳定。结论舒泰复合异氟烷吸入用于保留自主呼吸的小型猪气管插管是建立小型猪经口气道较好且安全的麻醉方法,具有推广价值。

机载光电复合旋转连接器设计技术研究

针对机载外挂平台设备系统光电信号旋转传输的使用需求,传统产品存在小型化、轻量化不足及高空环境下高电压易打火等问题,本文提出了机载光电复合旋转连接器一体化成型设计方法,通过中心轴与绝缘片、电刷架与绝缘片一体化结构设计,电接触可靠性及小偏角光纤准直器高效耦合设计,解决了传统光电旋转连接器无法满足机载设备狭小安装空间的小型化及耐高电压等技术难题,研制出了1光5电复合旋转连接器产品,能够满足高空18000 m环境下光电信号动态传输的使用要求,同时,产品随整机通过地面和飞行测试,效果良好。

巴马小型猪仰卧位的新型固定方法

目的 研究广西巴马小型猪仰卧位的固定方法以便于动物实验的开展。方法 选择行胸腔器官获取的广西巴马小型猪12头,接受全身麻醉后采用专用的固定装置进行仰卧位固定。结果 12头广西巴马小型猪在手术中体位得到很好的保持,未发生侧翻、移位等现象。结论 采用专用的固定装置对广西巴马小型猪进行仰卧位固定是一种简单有效的方法。

宽频小型化U形槽微带天线

针对微带贴片天线宽带化和小型化的设计需求,提出并设计了一种工作在S/C波段的改进的U形槽微带贴片天线。通过在辐射贴片中心开曲折U形槽,使缝隙和馈电探针偏离贴片中心,形成非对称曲折U形槽的层叠介质微带贴片天线。通过共面容性耦合馈电进一步提高天线的阻抗带宽。实测结果表明:该天线在3.11~5.40 GHz频率范围内回波损耗小于-10 dB,相对带宽可达53.8%,与仿真结果吻合,可为微带天线的小型化、宽带化设计提供参考。

基于半圆分形的柔性超宽带天线

以柔性材料聚酰亚胺(PI)作为介质基板材料,设计了一种柔性超宽带(UWB)半圆分形天线。天线辐射单元采用四阶半圆迭代嵌套分形结构,通过不同分形半圆调节电长度,增加天线的工作谐振点。通过在接地板开槽提高天线的阻抗匹配特性,实现UWB辐射。利用共面波导馈电方式提高天线的集成性。仿真与测试结果表明:所设计天线的阻抗带宽为2.98-10.61 GHz,带内全向增益达到5.58 dBi,天线最终尺寸为30 mm×24 mm,实现了小型化和可弯曲的特性,在共形于13 mm半径的圆柱后,天线仍能保持UWB辐射性能。

微型行星齿轮传动设计与分析

提出一种应用于某航空发动机中空气涡轮起动机的微型行星齿轮传动设计方案,对传动系统的构型进行结构设计、参数匹配;采用有限元分析软件ANSYS对其重要零部件进行强度校核,基于正交试验法对减速器结构进行优化,为微型行星减速结构在航空发动机起动机等航空产品中的推广与应用提供理论支撑。

无人机载轻小型遥感器的林业应用进展研究

聚焦于轻小型遥感器技术的发展,综述了无人机遥感技术在森林资源监测、健康评估和灾害管理等林业领域的应用进展。首先介绍了搭载于无人机的可见光、多光谱、高光谱、热红外和激光雷达等遥感器技术,阐述了其主要特性、显著优势和适用场景;然后深入探讨了这些遥感技术在林业管理中的具体应用,展示了其在提升森林监测效率和精确度以及在灾害响应和生态保护方面的重要作用;最后讨论了面临的主要挑战和发展需求,包括无人机平台的优化、遥感设备的改进、数据处理与信息提取技术的提升,强调了跨学科研究成果的综合应用对于推动遥感技术革新及其在林业中应用拓展的重要性;旨在为林业管理与研究人员提供一种全面的视角,审视无人机遥感技术的现状与未来趋势,进而支持森林资源的可持续管理与保护。

小型化低剖面全向滤波天线设计

设计了一个小型化全向微带滤波天线。天线由带通滤波器和微带天线组成,二者共用一个地平面以减小尺寸且采用缝隙耦合方式连接,带通滤波器蚀刻在微带贴片天线的馈线位置处,引入选频滤波功能,在输入馈线前端添加一个横向矩形贴片使整个系统达到良好的阻抗匹配。与传统的微带天线相比,所设计的滤波天线在不改变尺寸大小的基础上引入了选频滤波功能,在通带边缘体现出较高的选择性。仿真与测试结果表明,该滤波天线的阻抗带宽为2.31 GHz~2.56 GHz,且通带内增益平缓,平均增益约为2.1 dBi,在工作频段内呈全向辐射特性。

多层结构聚合物基复合电介质材料储能特性研究进展

聚合物电介质材料由于其成本低、击穿强度高、可靠性高等优点被广泛用于电力系统。但是聚合物电介质材料放电能量密度较低,难以满足新一代小型化电容器的需求,多层结构具有能够协同提升介电常数和击穿强度的优势,解决聚合物电介质介电常数与击穿强度之间的矛盾问题,实现具有优异储能特性的聚合物基电介质材料。文中综述了近年来多层结构聚合物基复合材料的研究进展,分析了多层结构中的极化与击穿现象,并详细讨论了聚合物基多层结构和无机层与聚合物基层结合的多层结构设计,归纳了一些能够提升多层结构聚合物基复合材料储能的方法。例如通过增加界面、优化多层结构中的填料分布以及构建过渡层的方法来提升储能特性。最后,对近年来多层结构聚合物基复合材料的进展进行了总结,并提出了未来的发展方向以及需要解决的关键问题。

作为景观的扶贫集体经济

有关研究多认识到部分扶贫集体经济作为景观而存在,但却未对其生成机制和实际影响开展系统的考察。我们认为,不少原贫困地区难以在短期内培育出具有发展潜力的集体经济是多种因素共同作用的结果。精准扶贫阶段设定的紧迫的脱贫时间线,既促进了部分贫困地区集体经济的快速成长,也导致了发展条件不成熟的地方制造了“扶贫景观”。另外,扶贫工作的考核验收方式进一步催生了作为景观的扶贫集体经济在发展条件相对落后地区的形成。在那些地区,基层政府一方面在辖区内大多数村庄打造简单景观以应对检查组的“普查”,另一方面集中扶贫资源在特定的村庄建设精致景观以回应上级的“抽查”。那些作为景观而存在的扶贫集体经济,主要是为应对验收而存在,难以真正成为乡村发展的动力。

小型化Ka波段行波管快启电子枪研究

针对弹载环境中毫米波行波管快速启动要求,利用ANSYS软件模拟电子枪阴极施加热丝功率对阴极温度产生的影响,并通过电子枪温度试验,定量测定热丝功率和阴极温度的对应关系,验证温度对阴极发射的影响。在模拟和试验基础上,开展电子枪小型化结构设计,成功研制出小型化毫米波弹载行波管用电子枪,使其满足弹载环境15 s快启功能。

有机化学绿色微量化研究:以“乙酸乙酯制备实验”为例

常量有机化学教学面临着“三废”问题,随着人们环保意识的不断提升绿色微量化教学显得尤为重要。在有机化学课程教学中,不断向学生输送绿色“小量-微量化”的教学理念,为学生后续的实验课程奠定坚实基础。以“乙酸乙酯的制备实验”为例,在教学中践行科创、绿色、微量“三合一”的举措,培养学生创新能力,增强学生环保及节约意识,提高学生自主学习能力。