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Iso-propagation vortices with OAM-independent size and divergence toward future faster optical communications

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Advanced Photonics 2024年第3期6卷 51-59页

作者： Wenxiang Yan Zhaozhong Chen Xian Long Yuan Gao Zheng Yuan Zhi-cheng Ren Xi-Lin Wang Jianping Ding Hui-tian Wang Nanjing University School of Physics National Laboratory of Solid State Microstructures Nanjing University Collaborative Innovation Center of Advanced Microstructures University of Glasgow James Watt School of Engineering Nanjing University Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics

Recognized in the 1990s, vortex beams' ability to carry orbital angular momentum(OAM) has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information communication. However, inherent diffraction in free space results in the inevitable expansion of beam size and divergence contingent upon the OAM, limiting vortex beams' applicability in areas such as spatial mode multiplexing communication, fiber-optic data transmission, and particle manipulation. These domains necessitate vortex beams with OAM-independent propagation *** introduce iso-propagation vortices(IPVs), vortex beams characterized by OAM-independent propagation behavior, achieved through precise radial index configuration of Laguerre–Gaussian beams. IPVs display notable transmission dynamics, including a reduced quality factor, resilience post-damage, and decreased and uniform modal scattering under atmospheric turbulence. Their distinctive attributes render IPVs valuable for potential applications in imaging, microscopy, optical communication, metrology, quantum information processing, and light–matter interactions. Notably, within optical communication, the case study suggests that the IPV basis, due to its OAM-independent propagation behavior, provides access to a more extensive spectrum of data channels compared with conventional spatial multiplexing techniques, consequently augmenting information capacity.

关键词： orbital angular momentum optical communication structured light optical vortices

500kV独山变电站无功补偿特性分析及改善措施研究

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贵州大学学报（自然科学版） 2015年第4期32卷 41-45页

作者：田茂城中国南方电网超高压输电公司贵阳局贵州贵阳550003

独山变电站的无功补偿系统难以满足南方电网对动态无功补偿的需求,应将并联电容器组和滤波电容器组断路器投切模式改为晶闸管投切模式,以扩大无功补偿的连续调节范围,提高变电站的动态无功补偿能力及交流系统母线电压的快速恢复能力,从... 详细信息

独山变电站的无功补偿系统难以满足南方电网对动态无功补偿的需求,应将并联电容器组和滤波电容器组断路器投切模式改为晶闸管投切模式,以扩大无功补偿的连续调节范围,提高变电站的动态无功补偿能力及交流系统母线电压的快速恢复能力,从而提升交流输电系统的稳定裕度。为此,本文设计一种基于晶闸管投切的动态无功补偿系统,并利用慢速导纳控制将SVC控制与MSC控制相结合,对全站动态无功补偿控制策略及其协调控制原则进行研究。同时,提出一种无功补偿装置协调控制原则,用以满足变电站对无功备用的需求,从而指导工程实际应用中容性无功功率补偿装置的投切。

关键词：静止无功补偿器慢速导纳控制动态无功补偿控制策略协调控制原则无功备用

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垂直U形管内气液两相流诱导振动模拟

工程热物理学报 2015年第10期36卷 2221-2225页

作者：马晓旭田茂诚张冠敏冷学礼山东大学能源与动力工程学院济南250061

采用ADINA数值方法研究了垂直U形管内气液两相流诱导振动的位移响应和脉动激振力特性,然后考察了雷诺数Re和体积含气率β对激振力的影响规律。结果表明:气液两相内流诱导振动以面内振动为主,表现为两相流诱发激振力的主频与管结构某阶... 详细信息

采用ADINA数值方法研究了垂直U形管内气液两相流诱导振动的位移响应和脉动激振力特性,然后考察了雷诺数Re和体积含气率β对激振力的影响规律。结果表明:气液两相内流诱导振动以面内振动为主,表现为两相流诱发激振力的主频与管结构某阶固有频率相近时的共振现象;激振力的脉动特性表现为低β时的窄频带随机波动和高β时的周期性波动;固定β时,激振力的均方根值F^(RMS)随Re的增大而增大,增大速率逐渐增加;同一Re下,F^(RMS)先随β的增大而增加,在β=55%左右时达到最大,之后逐渐降低,最大值出现在泡状流向搅拌流的转变过渡区。

关键词：气液两相流诱导振动脉动激振力流固耦合

Overexpression of the transcription factor MdWRKY115 improves drought and osmotic stress tolerance by directly binding to the MdRD22 promoter in apple

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Horticultural Plant Journal 2024年第3期10卷 629-640页

作者： Qinglong Dong Yi tian Xuemei Zhang Dingyue Duan He Zhang Kaiyu Yang Peng Jia Haoan Luan Suping Guo Guohui Qi Ke mao Fengwang Ma College of Forestry Hebei Agricultural UniversityBaodingHebei 071001China National Engineering Research Center for Agriculture in Northern Mountainous Areas Agricultural Technology Innovation Center in Mountainous Areas of Hebei ProvinceHebei Agricultural UniversityBaodingHebei 071001China State Key Laboratory of Crop Stress Biology for Arid Areas Shaanxi Key Laboratory of AppleCollege of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China College of Horticulture Hebei Agricultural UniversityBaodingHebei 071001China

Abiotic stress reduces plant yield and *** transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain ***,we functionally characterized the apple GroupⅢWRKY gene ***-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic *** activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic *** localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal *** analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic *** affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene *** binding was further verified by an electrophoretic mobility shift ***,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.

关键词： Apple MdWRKY115 Osmotic stress Drought stress Function analysis

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异形管束降膜流动流型及波长的分布规律

工程热物理学报 2015年第3期36卷 636-640页

作者：罗林聪张冠敏潘继红田茂诚山东大学能源与动力工程学院济南250061 重庆市计量质量检测研究院国家城市能源计量中心重庆401123

采用可视化方法对水的降膜流动过程进行了实验研究,考察了两异形管(蛋形管和滴形管)管间流型及其转变、降膜波长随Re数和管型的分布规律,并与圆管进行了对比分析。实验结果表明:各管的管间流型均随Re数的增大依次呈现滴状流、滴柱状流... 详细信息

采用可视化方法对水的降膜流动过程进行了实验研究,考察了两异形管(蛋形管和滴形管)管间流型及其转变、降膜波长随Re数和管型的分布规律,并与圆管进行了对比分析。实验结果表明:各管的管间流型均随Re数的增大依次呈现滴状流、滴柱状流、柱状流、柱片状流和片状流;相较于圆管,两异形管的各流型更易在较低的Re数下获得,且流型较稳定。随着Re数增加和管间距S的降低,降膜波长呈减小趋势。两异形管的降膜波长较圆管的低,且蛋形管的流型转变Re数最低。

关键词：异形管管间流型降膜波长两相流

Transformer and GAN-Based Super-Resolution Reconstruction Network for Medical Images

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Tsinghua Science and Technology 2024年第1期29卷 197-206页

作者： Weizhi Du Shihao tian Arts&Sciences College Washington University in St.LouisSt.LouisMO 63130USA Department of Electric and Computing Engineering Cornell UniversityIthacaNY 14850USA

Super-resolution reconstruction in medical imaging has become more demanding due to the necessity of obtaining high-quality images with minimal radiation dose,such as in low-field magnetic resonance imaging(MRI).However,image super-resolution reconstruction remains a difficult task because of the complexity and high textual requirements for diagnosis *** this paper,we offer a deep learning based strategy for reconstructing medical images from low resolutions utilizing Transformer and generative adversarial networks(T-GANs).The integrated system can extract more precise texture information and focus more on important locations through global image matching after successfully inserting Transformer into the generative adversarial network for picture ***,we weighted the combination of content loss,adversarial loss,and adversarial feature loss as the final multi-task loss function during the training of our proposed model *** comparison to established measures like peak signal-to-noise ratio(PSNR)and structural similarity index measure(SSIM),our suggested T-GAN achieves optimal performance and recovers more texture features in super-resolution reconstruction of MRI scanned images of the knees and belly.

关键词： super-resolution image reconstruction Transformer generative adversarial network(GAN)

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

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Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： tian Jing ZHANG Wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial *** the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation *** cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range *** principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

Biomaterials and tissue engineering in traumatic brain injury:novel perspectives on promoting neural regeneration

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Neural Regeneration Research 2024年第10期19卷 2157-2174页

作者： Shihong Zhu Xiaoyin Liu Xiyue Lu Qiang Liao Huiyang Luo Yuan tian Xu cheng Yaxin Jiang Guangdi Liu Jing Chen Department of Neurosurgery West China HospitalWest China Medical SchoolSichuan UniversityChengduSichuan ProvinceChina National Engineering Research Center for Biomaterials College of Biomedical EngineeringSichuan UniversityChengduSichuan ProvinceChina Department of Anesthesiology West China HospitalWest China Medical SchoolSichuan UniversityChengduSichuan ProvinceChina Department of Pharmacy West China HospitalWest China Medical SchoolSichuan UniversityChengduSichuan ProvinceChina Out-patient Department West China HospitalWest China Medical SchoolSichuan UniversityChengduSichuan ProvinceChina Department of Respiratory and Critical Care Medicine West China HospitalWest China Medical SchoolSichuan UniversityChengduSichuan ProvinceChina

Traumatic brain injury is a serious medical condition that can be attributed to falls, motor vehicle accidents, sports injuries and acts of violence, causing a series of neural injuries and neuropsychiatric symptoms. However, limited accessibility to the injury sites, complicated histological and anatomical structure, intricate cellular and extracellular milieu, lack of regenerative capacity in the native cells, vast variety of damage routes, and the insufficient time available for treatment have restricted the widespread application of several therapeutic methods in cases of central nervous system injury. Tissue engineering and regenerative medicine have emerged as innovative approaches in the field of nerve regeneration. By combining biomaterials, stem cells, and growth factors, these approaches have provided a platform for developing effective treatments for neural injuries, which can offer the potential to restore neural function, improve patient outcomes, and reduce the need for drugs and invasive surgical procedures. Biomaterials have shown advantages in promoting neural development, inhibiting glial scar formation, and providing a suitable biomimetic neural microenvironment, which makes their application promising in the field of neural regeneration. For instance, bioactive scaffolds loaded with stem cells can provide a biocompatible and biodegradable milieu. Furthermore, stem cells-derived exosomes combine the advantages of stem cells, avoid the risk of immune rejection, cooperate with biomaterials to enhance their biological functions, and exert stable functions, thereby inducing angiogenesis and neural regeneration in patients with traumatic brain injury and promoting the recovery of brain function. Unfortunately, biomaterials have shown positive effects in the laboratory, but when similar materials are used in clinical studies of human central nervous system regeneration, their efficacy is unsatisfactory. Here, we review the characteristics and properties

关键词： bioactive materials biomaterials exosomes neural regeneration scaffolds stem cells tissue engineering traumatic brain injury

Effects of Ta content on microstructure and oxidation behavior of AlCoCrFeNiYTax high entropy alloy

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Rare Metals 2024年第9期43卷 4462-4475页

作者： Cang Gu Jun-Hao Hu Jian-Bo Song cheng Xu Ming-Yu Hu Yu-Xuan Zhang Jiang tian Chao Li Jing Feng Faculty of Materials Science and Engineering Kunming University of Science and Technology Department of Physics Hong Kong Baptist University

The oxidation behavior of the Al Co Cr Fe Ni YTaxhigh entropy alloy（HEA） doped with different Ta contents at 1100 °C is investigated. In this study, different reasons for the spallation of the oxide scales of HEAs without/with excessive Ta addition after 1000 h of oxidation are discussed, and the most suitable Ta doping content for this HEA is explored, in which the HEA exhibits both an exceptionally low oxidation rate, and the formation of oxide scales composed of intact a-Al2O3. Meanwhile, it is found that the addition of Ta can effectively inhibit the phase transition of β phase, which makes the surface of the oxide scale smoother. By combining our experimental results with Wagner–Hauffe theory, the influence of Ta drag effect on oxide scale growth is explained, which provides some theoretical guidance for the subsequent design of Al Co Cr Fe Ni HEAs, and can lead to the development of thermal barrier coatings at higher service temperature.

关键词： Al2O3 scales Elements diffusion High-entropy alloy Oxidation