检索结果-内蒙古大学图书馆

Optimization of image reconstruction method for dual-particle time-encode imager through adaptive response correction

引用

NUCLEAR ENGINEERING AND TECHNOLOGY 2023年第5期55卷 1587-1592页

作者： Zhao, Dong Jia, Wenbao Hei, Daqian Cheng, Can Cheng, Wei liang, xuwen li, Ji Nanjing Univ Aeronaut & Astronaut Dept Nucl Sci & Technol Nanjing 211106 Peoples R China Lanzhou Univ Sch Nucl Sci & Technol Lanzhou 730000 Peoples R China Collaborat Innovat Ctr Radiat Med Jiangsu Higher E Suzhou 215000 Peoples R China Nucl Power Inst China Chengdu 610041 Peoples R China

Time-encoded imagers (TEI) are important class of instruments to search for potential radioactive sources to prevent illicit transportation and trafficking of nuclear materials and other radioactive sources. The energy of the radiation cannot be known in advance due to the type and shielding of source is unknown in practice. However, the response function of the time-encoded imagers is related to the energy of neutrons or gamma-rays. An improved image reconstruction method based on MLEM was proposed to correct for the energy induced response difference. In this method, the count vector versus time was first smoothed. Then, the preset response function was adaptively corrected according to the measured counts. Finally, the smoothed count vector and corrected response were used in MLEM to reconstruct the source distribution. A one-dimensional dual-particle time-encode imager was developed and used to verify the improved method through imaging an Am -Be neutron source. The improvement of this method was demonstrated by the image reconstruction results. For gamma-ray and neutron images, the angular resolution improved by 17.2% and 7.0%;the contrast-to-noise ratio improved by 58.7% and 14.9%;the signal-to-noise ratio improved by 36.3% and 11.7%, respectively.(c) 2023 Korean Nuclear Society, Published by Elsevier Korea LLC. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/4.0/).

关键词： Time -encoded imager Dual -particle imaging Response correction Image reconstruction

来源：评论

学校读者我要写书评

暂无评论

A General Route for Chemiluminescence of n-Type Au Nanocrystals

引用

ANALYTICAL CHEMISTRY 2022年第24期94卷 8811-8817页

作者： Fu, li Zhang, Bin Gao, xuwen Dong, Shuangtian Wang, Dongyang Zou, Guizheng Shandong Univ Sch Chem & Chem Engn Jinan 250100 Peoples R China

cence from nanocrystals (NCs) have been extensively exploited for both fundamental and applied investigation over two decades, while the understanding of chemiluminescence (CL) from NCs is still far from clear by now. Herein, a general route for triggering CL from NC luminophore is proposed by extensively exploiting the charge transfer between n-type NCs and oxidants. Oxidants, such as K2S2O8, H2O2, KMnO4, and NaClO, can chemically inject the hole onto the valence band (VB) of methionine-capped n-type AuNCs (Met@ AuNCs) and enable the occurrence of efficient radiative-charge-recombination between the chemically injected exogenous VB hole and the pre-existed endogenous conduction band (CB) electron, which eventually results in single-color and defect-involved CL with the maximum emission wavelength around 824 nm. The CL of Met@AuNCs/oxidant is qualified for ultrasensitive CL immunoassay in a similar procedure to the biotin???avidin and magnetic separation involved commercial CL immunoassay and exhibits acceptable performance for linearly determining carcinoembryonic antigen from 50 pg/mL to 100 ng/mL with a limit of detection of 10 pg/mL (S/N = 3). This strategy provides a general route to develop nanoparticulate CL luminophores and might eventually enable CL multiplexing assay via extensively exploiting the CL of different wavebands.

关键词： Nanocrystal Electrochemiluminescence Electroluminescence Chemiluminescence

来源：评论

学校读者我要写书评

暂无评论

Dynamic Channel Reservation Strategy Based on DQN Algorithm for Multi-Service LEO Satellite Communication System

引用

IEEE WIRELESS COMMUNICATIONS LETTERS 2021年第4期10卷 770-774页

作者： li, Zongwang Xie, Zhuochen liang, xuwen Chinese Acad Sci Shanghai Engn Ctr Microsatellites Shanghai 201210 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

In this letter, a dynamic channel reservation (DCR) strategy based on deep Q network (DQN) is proposed for multi-service low earth orbit (LEO) satellite communication system. We develop a novel modeling method to represent DCR problem of multiple services as a reinforcement learning (RL) task. Based on this model, we calculate the influence of current channel allocation results on future environment and take it as one of the factors for channel allocation decision. Moreover, a corresponding neural network is designed as a decision evaluator to provide an end to end mapping of decision to its value, which effectively avoids the influence of artificial preconditions. Simulation results show that the proposed strategy can improve the overall quality of service (QOS) of the system.

关键词： Satellites Bandwidth Handover Low earth orbit satellites Channel allocation Resource management Heuristic algorithms Multi-service LEO satellite dynamic channel reservation strategy deep Q network

来源：评论

学校读者我要写书评

暂无评论

The complete chloroplast genome of the lipstick tree,Bixa Orellana(Bixaceae)

引用

Mitochondrial DNA Part B 2019年第1期4卷 17-18页

作者： Seping Dai xuwen li Jianzhong Ni lin Ruan Renchao Zhou Wei Lun Ng Guangzhou Institute of Forestry and Landscape Architecture Guangzhou China State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources School of Life Science Sun Yat-sen University Guangzhou China

Bixa orellanais a small tree known for its red, oil-soluble pigment contained in the seed coat that is used as a natural dye and food coloring. In this study, we assembled and characterized the complete chloroplast genome ofB. orellanaas a resource for future genetic studies. With a total length of 159,825 bp, the chloroplast genome comprised of a large single-copy (LSC) region of 89,476 bp, a small single-copy (SSC) region of 19,617 bp, and two inverted repeat (IR) regions of 25,356 bp each. A total of 127 genes were predicted, consisting of 83 protein-coding genes, 36 tRNA genes, and 8 rRNA genes. Phylogenetic analysis confirmed the position ofB. orellanawithin the order Malvales.

关键词： Bixa achiote natural dye complete chloroplast genome automated assembly

来源：评论

学校读者我要写书评

暂无评论

Mid-Miocene (17-11 Ma) fast exhumation in the upper Jinsha River and its implication for regional faulting in Southeast Tibet

引用

GEOMORPHOLOGY 2024年 466卷

作者： Shen, xuwen Jing, liu-Zeng Shen, Xiaoming Zeng, Xianyang Wang, Zijun Xing, Yukun Wang, Heng li, Mohan Tianjin Univ Sch Earth Syst Sci Tianjin 300072 Peoples R China Minist Emergency Management China Natl Inst Nat Hazards Beijing 100085 Peoples R China China Earthquake Adm Inst Geol State Key Lab Earthquake Dynam Beijing 100029 Peoples R China Univ Melbourne Sch Geog Earth & Atmospher Sci Parkville Vic 3010 Australia

The rugged southeast (SE) Tibet hosts a network of evolving faults, many of which are poorly understood due to a lack of sedimentary records and poor accessibility. The Jinsha River fault zone (JRFZ) is vaguely considered as a major fault bounding the Chuan-Dian Block in the northwest, yet little is known about its tectonic evolution history, which hinders our clear understanding of the tectonic deformation pattern, process and geomorphic response of SE Tibet. Here, we collected 10 samples from the hanging wall of the Xiongsong reverse fault, one strand of the JRFZ, near Markam area and on the trunk of the upper Jinsha River, to reveal its exhumation and kinematic history through low-temperature thermochronology. The ZHe ages (similar to 17-13 Ma) of the samples from the hanging wall are much younger than the published ones in the footwall, but the AFT (similar to 11-9 Ma) and AHe ages (similar to 14-6 Ma) are only slightly younger than those in the footwall. The QTQt and 3-D thermo-kinematic Pecube modeling suggest consistently that the Xiongsong fault experienced strong activity during the mid-Miocene (similar to 17-11 Ma) and then weakened. Post-11 Ma decreases in exhumation here on the trunk of the Jinsha river, if interpreted as river incision, is opposite to previously inferred river response to late Miocene surface uplift driven by the lower crust flow. Significant differences in thermochronological data and modeling results on both sides of the Jinsha River indicate the importance of local faulting in the development of large rivers. In addition, late Miocene fault activity shifts have also been observed on other major structures in SE Tibet, such as the left-lateral faulting of the Xianshuihe-Xiaojiang fault, the enhanced thrusting of the Longmen Shan-Yalong thrust belt and the kinematic reversal of the Ailao Shan-Red River shear zone. We infer that the near synchronized change in regional fault activity may be caused by the clockwise rotation of SE Tibet,

关键词： Southeastern Tibet Chuan-Dian Block Jinsha River fault zone Low-temperature thermochronology Late Miocene

来源：评论

学校读者我要写书评

暂无评论

Research on the three-dimensional visual management and control for marine intelligent mould bed based on digital twin

引用

SHIPS AND OFFSHORE STRUCTURES 2024年第6期19卷 756-768页

作者： Zhou, Honggen Yan, Zhanghui Jing, xuwen Chen, Yu liu, Jinfeng Zou, Xiaofeng Kang, Chao li, Bingqiang Xie, Yang Yan, Dejun Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang Peoples R China CSSC Huangpu Wenchong Shipbuilding Co Ltd Guangdong Prov Key Lab Adv Welding Technol Ships Guangzhou Peoples R China Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212100 Jiangsu Peoples R China

Mould bed is crucial for supporting the ship subsection and controlling its deformation during shipbuilding. However, its visualisation and control process intelligence are often inadequate, leading to reduced accuracy and efficiency in ship subsection construction. Aiming at the problem, a three-dimensional (3D) visual monitoring method for the marine intelligent mould bed is proposed based on digital twin, and the overall framework of the management and control system is designed. Meanwhile, a fuzzy PID control principle optimised by the genetic algorithm is proposed to better control the deformation of the ship subsection. On this basis, the verification of the developed system is carried out based on the physical intelligent mould bed, and the 3D visual management and control of the marine intelligent mould bed are realised. It provides a foundation for improving the accuracy and efficiency of ship subsection construction.

关键词： Digital twin intelligent mould bed management and control system visual monitoring adaptive control

来源：评论

学校读者我要写书评

暂无评论

A Wide Range and High Repeatability MEMS Pressure Sensor Based on Graphene

引用

IEEE SENSORS JOURNAL 2022年第18期22卷 17737-17745页

作者： Zhu, Zehua Wang, Junqiang Wu, Chenyang Chen, xuwen liu, Xiaofei li, Mengwei North Univ China Natl Key Lab Instrumentat Sci & Dynam Measurement Taiyuan 030051 Peoples R China North Univ China Acad Adv Interdisciplinary Res Taiyuan 030051 Peoples R China

Graphene pressure sensors have attracted extensive attention due to their excellent performance. However, the range and linearity of conventional suspension graphene pressure sensors are too small to meet commercial requirements. In this article, we propose a wide range and high repeatability MEMS pressure sensor based on graphene array structure. Single-layer chemical vapor deposition (CVD) graphene was transferred at the root of silicon pressure-bearing elastic diaphragm, and it was simultaneously protected by the Si3N4 nanofilm. In addition, the Au/Sn eutectic bonding technology was employed to complete the hermetic package of the sensor. Pressure tests showed that the repeatability error of the pressure sensor in the range of 0-20 MPa was 4.062% full scale output (FSO) and the hysteresis was 2.118% FSO. Furthermore, the temperature resistance studies confirmed that the Si3N4 nanofilm can effectively protect graphene due to its extremely high thermal stability. And with excellent characteristics of high long-term stability, it can work stably in humid environments. Conclusionally, this research provides significant exploration to promote the practicality and commercialization of graphene devices.

关键词： Graphene high repeatability MEMS pressure sensors wide range

来源：评论

学校读者我要写书评

暂无评论

Corrigendum to“Temporal assembly patterns of microbial communities in three parallel bioreactors treating low-concentration coking wastewater with differing carbon source concentrations”[Journal of Environmental Sciences,Volume 137,March 2024,Pages 455-468]

引用

Journal of Environmental Sciences 2024年第3期36卷 701-702页

作者： Weijia li Yu Xia Na li Jie Chang Jing liu Pei Wang xuwen He School of Chemical and Environmental Engineering China University of Mining and Technology-BeijingBeijing 100083China

The authors regret that the first line of Fig.7 has an extra“toluene”.The correct Fig.7 is provided as below.

关键词： wastewater source carbon

来源：评论

学校读者我要写书评

暂无评论

The Imaging Features and Diagnostic Value of Computerised Tomography in Seminal Duct Tuberculosis

引用

JOURNAL OF MULTIDISCIPliNARY HEALTHCARE 2023年 16卷 1395-1402页

作者： Qi, Min Zhang, Le Gan, Wei Xu, Yanling Wei, Jialu Fu, xuwen li, Xiang Third Peoples Hosp Kunming Yunnan Clin Med Ctr Infect Dis Dept Radiol 319 Wujing St Kunming 650041 Peoples R China Third Peoples Hosp Kunming Yunnan Clin Med Ctr Infect Dis Dept ICU Kunming 650041 Peoples R China

Objective: To analyse the computerised tomography (CT) imaging features and diagnostic value of seminal duct tuberculosis (TB). Methods: The imaging data of male patients with ejaculatory duct TB who underwent surgical treatment in our hospital from 1 January 2019 to 31 December 2019 were retrospectively analysed. Through CT images, seminal duct TB was divided into different types, and the CT image features of different types of TB were analysed. The differences in diagnosis between CT and pathological results were compared. Results: According to the CT manifestations of TB of the intrapelvic segment of seminal duct TB, this disease could be divided into an intra-tubular calcification type, a lumen dilatation and effusion type and a wall thickening type, among which 6 cases (15.8%) were intra-tubular calcification types, 14 cases (36.8%) were lumen dilatation and effusion types and 18 cases (47.4%) were wall thickening types. The diagnostic efficacy of CT in the diagnosis of ejaculatory duct TB: sensitivity = 63.89% (23/36), specificity = 80.01% (44/53), accuracy = 75.28% (67/89), positive predictive value = 51.87% (43/109), negative predictive value = 77.19% (44/57) and kappa = ***: CT has high sensitivity and specificity in the diagnosis of seminal duct TB. The classification of seminal duct TB using CT images is of great significance for the diagnosis and treatment of the disease.

关键词： seminal duct tuberculosis computerised tomography

来源：评论

学校读者我要写书评

暂无评论

Discovery of Chalcone Derivatives as Bifunctional Molecules with Anti-SARS-CoV-2 and Anti-inflammatory Activities

引用

JOURNAL OF NATURAL PRODUCTS 2024年第12期87卷 2680-2694页

作者： Chen, xuwen li, Hongtao Wang, Meiting Sun, Donghui Lu, Jiani Zhu, Tong Chen, Hongzhuan Chen, lili liu, Shunying East China Normal Univ Shanghai Engn Res Ctr Mol Therapeut & New Drug Dev Sch Chem & Mol Engn Shanghai 200062 Peoples R China Shanghai Univ Tradit Chinese Med Inst Interdisciplinary Integrat Med Res Shanghai Frontiers Sci Ctr TCM Chem Biol Longhua Hosp Shanghai 201203 Peoples R China Shanghai Univ Tradit Chinese Med Shanghai Inst Infect Dis & Biosecur Inst Interdisciplinary Integrat Med Res Shanghai Frontiers Sci Ctr TCM Chem Biol Shanghai 201203 Peoples R China

Danshensu extracted with traditional Chinese medicine Salvia miltiorrhiza has a wide range of bioactivities. Danshensu containing a catechol moiety has a moderate inhibitory effect on SARS-CoV-2 3CLpro (IC50 = 2.2 mu M) by a reversible covalent interaction and exhibits good anti-inflammatory activity. To enhance the inhibitory activity, we introduced Michael receptors into the side chain of danshensu as a possible covalent warhead and blocked the covalent binding sites of catechol moiety to yield chalcone derivatives. The resulting chalcone derivatives, A4 and A7, were found to inhibit SARS-CoV-2 3CLpro in vitro with IC50 values of 83.2 and 261.3 nM, respectively. Furthermore, A4 and A7 inhibit viral replication in the SARS-CoV-2 replicon system with EC50 values of 19.9 and 11.7 mu M, respectively. Time-dependent inhibition experiment and mass spectrometry show that A4 acted as a noncovalent mixed inhibitor, while A7 likely binds covalently at Cys145. The interaction mechanism between SARS-CoV-2 3CLpro and A4 or A7 was characterized by molecular docking studies. Additionally, both A4 and A7 demonstrated potent anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. These promising results suggest that chalcone derivatives A4 and A7 can serve as bifunctional molecules with both antivirus and anti-inflammatory properties.

关键词：

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：