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High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin He Lin-sen Ye Xiao-Feng yang Jia-Jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Immunogenicity and safety of NVSI-06-07 as a heterologous booster after priming with BBIBP-CorV:a phase 2 trial

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Signal Transduction and Targeted Therapy 2022年第7期7卷 2522-2532页

作者： Nawal Al Kaabi Yun Kai yang Jing Zhang Ke Xu Yu Liang Yun Kang Ji Guo Su Tian yang Salah Hussein Mohamed Saif ElDein Shuai Shao sen sen yang Wenwen Lei Xue Jun Gao Zhiwei Jiang Hui Wang Meng Li Hanadi Mekki Mekki Walid Zaher Sally Mahmoud Xue Zhang Chang Qu Dan Ying Liu Jing Zhang Mengjie yang Islam Eltantawy Peng Xiao Zhao Nian Wang Jin Liang Yin Xiao Yan Mao Jin Zhang Ning Liu Fu Jie Shen Liang Qu Yun Tao Zhang Xiao Ming yang Guizhen Wu Qi Ming Li Sheikh Khalifa Medical City SEHAAbu DhabiUnited Arab Emirates College of Medicine and Health Sciences Khalifa UniversityAbu DhabiUnited Arab Emirates China National Biotec Group Company Limited BeijingChina The Sixth Laboratory National Vaccine and Serum Institute(NVSI)BeijingChina National Engineering Center for New Vaccine Research BeijingChina National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention(China CDC)BeijingChina Lanzhou Institute of Biological Products Company Limited LanzhouChina Beijing Key Tech Statistical Consulting Co. LtdBeijingChina Beijing Institute of Biological Products Company Limited BeijingChina Union 71 Abu DhabiUnited Arab Emirates G42 Healthcare Abu DhabiUnited Arab Emirates

The increased coronavirus disease 2019(COVID-19)breakthrough cases pose the need of booster *** conducted a randomised,double-blinded,controlled,phase 2 trial to assess the immunogenicity and safety of the heterologous prime-boost vaccination with an inactivated COVID-19 vaccine(BBIBP-CorV)followed by a recombinant protein-based vaccine(NVSI-06-07),using homologous boost with BBIBP-CorV as *** groups of healthy adults(600 individuals per group)who had completed two-dose BBIBP-CorV vaccinations 1–3 months,4–6 months and≥6 months earlier,respectively,were randomly assigned in a 1:1 ratio to receive either NVSI-06-07 or BBIBP-CorV *** assays showed that in NVSI-06-07 groups,neutralizing antibody geometric mean titers(GMTs)against the prototype SARS-CoV-2 increased by 21.01–63.85 folds on day 28 after vaccination,whereas only 4.20–16.78 folds of increases were observed in control *** Omicron variant,the neutralizing antibody GMT elicited by homologous boost was 37.91 on day 14,however,a significantly higher neutralizing GMT of 292.53 was induced by heterologous *** results were obtained for other SARS-CoV-2 variants of concerns(VOCs),including Alpha,Beta and *** heterologous and homologous boosters have a good safety *** and systemic adverse reactions were absent,mild or moderate in most participants,and the overall safety was quite similar between two booster *** findings indicated that NVSI-06-07 is safe and immunogenic as a heterologous booster in BBIBP-CorV recipients and was immunogenically superior to the homologous booster against not only SARS-CoV-2 prototype strain but also VOCs,including Omicron.

关键词： phase neutral GMT

Drone-YOLOv7: small target detection in UAV remote sensing images using YOLOv7-tiny with dynamic head

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Optoelectronics Letters 2025年

作者： yang Ye yang sen Tong Jigang Wang Zenghui Tianjin University of Technology Department of Electrical Engineering， University of South Africa

In the task of detecting targets in unmanned aerial vehicles （UAVs） aerial images， the challenge arises from small size and wide scale span of targets， making their location， extraction and feature distinction difficult. Similar categories are susceptible to confusion. To address these issues， an improved YOLOv7-tiny aerial detection algorithm is proposed. Firstly， to improve the identification of small targets， a small target detection layer is added while removing the maximum target detection layer to enhance the localization ability of small targets and make the model lightweight. Secondly， a CBAM （Convolutional Block Attention Module） attention mechanism is incorporated at the connection between the backbone and neck to focus on the target area and eliminate interference. Additionally， to further enhance the classification and location capabilities of the targets， the detection head is replaced with a dynamic head （DYHead） with a unified channel number to fuse scale， space and task awareness in a single module. Finally， to overcome the difficulty of extracting features， the neck is replaced with a CS-FPN （Cross-Scale Feature Pyramid Network） structure with cross-scale connections to amplify feature fusion. Comparative experiments on the VisDrone2021 dataset show that the proposed model can improve mAP50and mAP0.5:0.95by 8.3% and 6.1%， respectively， compared to the original YOLOv7-tiny model， and significant improvements are also observed on CARPK and SeaDronesSee datasets.

关键词：

Point-voxel dual transformer for LiDAR 3D object detection

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Optoelectronics Letters 2025年

作者： Tong Jigang yang Fanhang yang sen Du Shengzhi Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems and Intelligent Robot La-boratory， Tianjin University of Technology， 391 Binshui West Road Department of Electrical Engineering， Tshwane University of Technology

Deep learning for point clouds faces the challenge of their inherent unordered nature， which makes traditional CNN-like methods not directly applicable. However， due to the inherent permutation invariance， transformers provide solutions to unordered points problems faced in LiDAR-based object detection. In this paper， a two-stage LiDAR 3D object detection framework is presented， namely Point-Voxel Dual Transformer (PV-DT3D)， which is a transformer-based method. In the proposed PV-DT3D， point-voxel fusion features are used for proposal refinement. Specifically， in the PV-DT3D， keypoints are sampled from entire point cloud scene and used to encode representative scene features via a proposal-aware voxel set abstraction module. Subsequently， following the generation of proposals by the region proposal networks (RPN)， the internal encoded keypoints are fed into dual transformer encoder-decoder architecture. In 3D object detection， the proposed PV-DT3D is the first to take advantage of both pointwise transformer and channel-wise architecture to capture contextual information from the perspective of spatial and channel dimensions. Experiments conducted on the highly competitive KITTI 3D car detection leaderboard show that， the PV-DT3D achieves superior detection accuracy among state-of-the-art point-voxel-based methods.

关键词：

Hyperbolic cosine transformer for LiDAR 3D object detection

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Optoelectronics Letters 2025年

作者： Tong Jigang yang Fanhang yang sen Du Shengzhi Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems and Intelligent Robot Laboratory， Tianjin University of Technology Department of Electrical Engineering， Tshwane University of Technology

Recently， Transformer has achieved great success in computer vision. However， it is constrained because the spatial and temporal complexity grows quadratically with the number of large points in 3D object detection applications from point clouds. Previous point-wise methods are suffering from time consumption and limited receptive fields to capture information among points. To address these limitations， we propose the cosh-attention， which reduces the computation complexity of space and time from the quadratic order to linear order with respect to the number of points. In the cosh-attention， the traditional softmax operator is replaced by non-negative ReLU activation and hyperbolic-cosine-based operator with re-weighting mechanism. Then based on the key component， cosh-attention， we present a two-stage hyperbolic cosine transformer (ChTR3D) for 3D object detection from point clouds. It refines proposals by applying cosh-attention in linear computation complexity to encode rich contextual relationships among points. Extensive experiments on the widely used KITTI dataset and Waymo Open Dataset demonstrate that， compared with vanilla attention， the cosh-attention significantly improves the inference speed with competitive performance. Experiment results show that， among two-stage state-of-the-art methods using point-level features to refine proposals， the proposed ChTR3D is the fastest one.

关键词：

d-玻色子体系波函数的SU2SU2基、物理基与无迹玻色子算符（Ⅲ）

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高能物理与核物理 1983年第4期 489-499页

作者：杨泽森北京大学物理系

本文把前文（Ⅰ）及（Ⅱ）发展的方法和获得的结果应用于原子核的相互作用玻色子模型（IBM）。我们采用SU6（?）U5（?）O5（?）O3表象,把求IBM哈密顿量矩阵元的问题归结为求d玻色子的一些基本矩阵元,并针对d玻色子体系的现有几类物理基... 详细信息

本文把前文（Ⅰ）及（Ⅱ）发展的方法和获得的结果应用于原子核的相互作用玻色子模型（IBM）。我们采用SU6（?）U5（?）O5（?）O3表象,把求IBM哈密顿量矩阵元的问题归结为求d玻色子的一些基本矩阵元,并针对d玻色子体系的现有几类物理基建立了两种求基本矩阵元的方法,求出了相应的明显表达式.

关键词：玻色子高能物理核物理 IBM SU2 矩阵元基矢波函数波动力学算符无迹

Dyson玻色子展开与原子核的相互作用玻色子模型

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高能物理与核物理 1985年第3期 341-348页

作者：杨泽森北京大学物理系

根据修正的Jancovici-Schiff(MJS)代换关于玻色子描述可以用作原子核的费米子描述的中间步骤的观点,本文把相互作用玻色模型(IBM)看作在这种中间步骤引用的一种近似.文中针对同类价核子的“多-j”组态以及包含两体有效相互作用的赘米子... 详细信息

根据修正的Jancovici-Schiff(MJS)代换关于玻色子描述可以用作原子核的费米子描述的中间步骤的观点,本文把相互作用玻色模型(IBM)看作在这种中间步骤引用的一种近似.文中针对同类价核子的“多-j”组态以及包含两体有效相互作用的赘米子哈密顿量,按照通常的玻色子展开选择出结构上比较简单的玻色子哈密顿量;借此通过一个么正变换建立了从微观途径确定s,d玻色子及IBM哈密顿量的方法;根据MJS代换给出了把IBM态矢量变换为费米子态矢量的一般公式.

关键词：玻色子 Dyson 哈密顿量价核子费米子态矢量壳模型核子数对易关系本征值

d-玻色子体系波函数的SU2■SU2基、物理基与无迹玻色子算符（Ⅱ）

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高能物理与核物理 1983年第2期 245-256页

作者：杨泽森北京大学物理系

为了完满地解决求现有几类物理基矢在SUSU2表象的表示问题,文中从第一类|PPO3>基矢的无迹玻色子算符形式出发,直接求出内积的明显表达式。同时用这种基矢的迭加表示出第二类基矢|PP（y）LL},和用的相应的迭加表示出详细信息

为了完满地解决求现有几类物理基矢在SUSU2表象的表示问题,文中从第一类|PPO3>基矢的无迹玻色子算符形式出发,直接求出内积的明显表达式。同时用这种基矢的迭加表示出第二类基矢|PP（y）LL},和用的相应的迭加表示出

关键词：基矢态矢量迭加玻色子波函数波动力学 SU2 算符无迹

Safety and immunogenicity of a mosaic vaccine booster against Omicron and other SARS-CoV-2 variants:a randomized phase 2 trial

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Signal Transduction and Targeted Therapy 2023年第2期8卷 672-682页

作者： Nawal Al Kaabi Yun Kai yang Yu Liang Ke Xu Xue Feng Zhang Yun Kang Yu Qin Jin Jun Wei Hou Jing Zhang Tian yang Salah Hussein Mohamed Saif ElDein Ze Hua Lei Hao Zhang Shuai Shao Zhao Ming Liu Ning Liu Xiang Zheng Ji Guo Su sen sen yang Xiangfeng Cong Yao Tan Wenwen Lei Xue Jun Gao Zhiwei Jiang Hui Wang Meng Li Hanadi Mekki Mekki Walid Zaher Sally Mahmoud Xue Zhang Chang Qu Dan Ying Liu Jing Zhang Mengjie yang Islam Eltantawy Peng Xiao Fu Jie Shen Jin Juan Wu Zi Bo Han Li Fang Du Fang Tang Shi Chen Zhi Jing Ma Fan Zheng Ya Nan Hou Xin Yu Li Xin Li Zhao Nian Wang Jin Liang Yin Xiao Yan Mao Jin Zhang Liang Qu Yun Tao Zhang Xiao Ming yang Guizhen Wu Qi Ming Li Sheikh Khalifa Medical City SEHAAbu DhabiUAE College of Medicine and Health Sciences Khalifa UniversityAbu DhabiUAE China National Biotec Group Company Limited BeijingChina The Sixth Laboratory National Vaccine and Serum Institute(NVSI)BeijingChina National Engineering Center for New Vaccine Research BeijingChina National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention(China CDC)BeijingChina Clinical Medicine Office National Vaccine and Serum Institute(NVSI)BeijingChina Lanzhou Institute of Biological Products Company Limited LanzhouChina Beijing Key Tech Statistical Consulting Co. LtdBeijingChina Beijing Institute of Biological Products Company Limited BeijingChina Union 71 Abu DhabiUAE G42 Healthcare Abu DhabiUAE

An ongoing randomized,double-blind,controlled phase 2 trial was conducted to evaluate the safety and immunogenicity of a mosaic-type recombinant vaccine candidate,named NVSI-06-09,as a booster dose in subjects aged 18 years and older from the United Arab Emirates(UAE),who had administered two or three doses of inactivated vaccine BBIBP-CorV at least 6 months prior to *** participants were randomly assigned with 1:1 to receive a booster dose of NVSI-06-09 or *** primary outcomes were immunogenicity and safety against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron variant,and the exploratory outcome was cross-immunogenicity against other circulating *** May 25 and 30,2022,516 adults received booster vaccination with 260 in NVSI-06-09 group and 256 in BBIBP-CorV *** results showed a similar safety profile between two booster groups,with low incidence of adverse reactions of grade 1 or *** immunogenicity,by day 14 post-booster,the fold rises in neutralizing antibody geometric mean titers(GMTs)from baseline elicited by NVSI-06-09 were remarkably higher than those by BBIBP-CorV against the prototype strain(19.67 vs 4.47-fold),Omicron BA.1.1(42.35 vs 3.78-fold),BA.2(25.09 vs 2.91-fold),BA.4(22.42 vs 2.69-fold),and BA.5 variants(27.06 vs 4.73-fold).Similarly,the neutralizing GMTs boosted by NVSI-06-09 against Beta and Delta variants were also 6.60-fold and 7.17-fold higher than those by *** findings indicated that a booster dose of NVSI-06-09 was well-tolerated and elicited broad-spectrum neutralizing responses against divergent SARS-CoV-2 variants,including Omicron and its sub-lineages.

关键词： phase neutral spectrum