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Defence Technology（防务技术） 2024年第7期37卷 162-172页

作者： Pengyu Hu Jiangpeng Wu Zhengang yan Meng He Chao Liang Hao bai Xi'an Modern Control Technology Research Institute Xi'an710065China Xi'an OET Science and Technology Co. LtdXi'an710076China

High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high ***,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment *** address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo ***,background difference algorithm is utilized to extract the center and area of each fragment in the image ***,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment *** reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial ***,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.

关键词： Warhead fragment measurement High speed photography Stereo vision Multi-object tracking Spatio-temporal reconstruction

Retrieval of Antarctic sea ice freeboard and thickness from HY-2b satellite altimeter data

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Acta Oceanologica Sinica 2024年第3期43卷 87-101页

作者： Yizhuo Chen Xiaoping Pang Qing Ji Zhongnan yan Zeyu Liang Chenlei Zhang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China Key Laboratory of Polar Environment Monitoring and Public Governance Ministry of EducationWuhan 430079China 4 School of Geography and Tourism Anhui Normal UniversityWuhu 241002China

Antarctic sea ice is an important part of the Earth’s atmospheric system,and satellite remote sensing is an important technology for observing Antarctic sea *** Chinese Haiyang-2b(HY-2b)satellite altimeter data could be used to estimate sea ice freeboard and provide alternative Antarctic sea ice thickness information with a high precision and long time series,as other radar altimetry satellites can,needs further *** paper proposed an algorithm to discriminate leads and then retrieve sea ice freeboard and thickness from HY-2b radar altimeter *** first collected the Moderate-resolution Imaging Spectroradiometer ice surface temperature(IST)product from the National Aeronautics and Space Administration to extract leads from the Antarctic waters and verified their accuracy through Sentinel-1 Synthetic Aperture Radar ***,a surface classification decision tree was generated for HY-2b satellite altimeter measurements of the Antarctic waters to extract leads and calculate local sea surface *** then estimated the Antarctic sea ice freeboard and thickness based on local sea surface heights and the static equilibrium ***,the retrieved HY-2b Antarctic sea ice thickness was compared with the CryoSat-2 sea ice thickness and the Antarctic Sea Ice Processes and Climate(ASPeCt)ship-based observed sea ice *** results indicate that our classification decision tree constructed for HY-2b satellite altimeter measurements was reasonable,and the root mean square error of the obtained sea ice thickness compared to the ship measurements was 0.62 *** proposed sea ice thickness algorithm for the HY-2b radar satellite fills a gap in this application domain for the HY-series satellites and can be a complement to existing Antarctic sea ice thickness products;this algorithm could provide long-time-series and large-scale sea ice thickness data that contribute to research on global climate change.

关键词： HY-2b satellite altimeter classification decision tree sea ice freeboard and thickness Antarctic waters

Atomic-scale mechanism of effect of co-separation of elements at interface of ferrite and austenite on Cr-depleted zone of duplex stainless steel

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Journal of Iron and Steel Research(International) 2024年第3期31卷 710-718页

作者： yan-hui Hou Ze-kun Xu Shi-long Zhou Guang-qiang Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Three-dimensional atom-probe tomography and first-principles calculation combined with density functional theory were used to study the effect of the co-segregation of different elements formed during the solidification process of S32205 duplex stainless steel on the Cr-depleted zone at the interface between ferrite and *** was found that the co-segregation of different elements formed during the solidification process of duplex stainless steel can also form Cr-depleted zone at the interface between ferrite and ***,Mo,Si,b,C and P atoms promote co-segregation with Cr atoms,which promotes the formation of Cr-depleted zone at the interface between ferrite and austenite in duplex stainless *** and Si strongly promote the segregation of Cr at the interface between ferrite and austenite,thereby promoting the formation of Cr-depleted zone.b,C and P elements also promote the segregation of Cr element at the interface between ferrite and austenite and the formation of Cr-depleted zone,but their effect is weaker than that of Mo and Si *** conclusions provide a new theoretical basis for improving the intergranular corrosion performance of duplex stainless steel.

关键词： Duplex stainless steel Cr-depleted zone Intergranular corrosion Co-segregation First-principles calculation

Imaging plate scanners calibration and the attenuation behavior of imaging plate signals

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Chinese Physics b 2024年第6期33卷 38-44页

作者：薄楠王乃彦 College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China China Institute of Atomic Energy Beijing 102413China

based on previously reported work, we propose a new method for calibrating image plate(IP) scanners, offering greater flexibility and convenience, which can be extended to the calibration tasks of various scanner models. This method was applied to calibrate the sensitivity of a GE Typhoon FLA 7000 scanner. Additionally, we performed a calibration of the spontaneous signal attenuation behavior for bAS-MS, bAS-SR, and bAS-TR type IPs under the 20±1℃ environmental conditions, and observed significant signal carrier diffusion behavior in bAS-MS IP. The calibration results lay a foundation for further research on the interaction between ultra-short, ultra-intense lasers and matter.

关键词： image plate scanner ultra-short ultra-intense lasers

Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients

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World Journal of Gastroenterology 2024年第23期30卷 3005-3015页

作者： yan-Fen Xu Hui-Yun Ma Gui-Ling Huang Yu-Ting Zhang Xue-yan Wang Ming-Jie Wei Xiao-Qing Pei Department of Ultrasound State Key Laboratory of Oncology in South ChinaGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina Department of Radiology State Key Laboratory of Oncology in South ChinaGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina Department of Medical Ultrasound State Key Laboratory of Oncology in South ChinaGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina

bACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the *** disease poses a serious public health problem in China,ranking fifth for incidence and third for *** of the invasive depth of the tumor is vital to treatment *** To evaluate the diagnostic performance of double contrast-enhanced ultrasonography(DCEUS)for preoperative T staging in patients with GC by comparing with multi-detector computed tomography(MDCT).METHODS This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March *** underwent DCEUS,including ultrasonography(US)and intravenous contrast-enhanced ultrasonography(CEUS),and MDCT examinations for the assessment of preoperative T *** of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging *** diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold *** A total of 229 patients with GC(80 T1,33 T2,59 T3 and 57 T4)were *** accuracies were 86.9%for DCEUS and 61.1%for MDCT(P<0.001).DCEUS was superior to MDCT for T1(92.5%vs 70.0%,P<0.001),T2(72.7%vs 51.5%,P=0.041),T3(86.4%vs 45.8%,P<0.001)and T4(87.7%vs 70.2%,P=0.022)staging of *** DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT,and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making.

关键词： Double contrast-enhanced ultrasonography Multi-detector computed tomography Gastric cancer T staging

A low-profile metamaterial absorber with ultrawideband reflectionless and wide-angular stability

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Defence Technology（防务技术） 2024年第4期34卷 258-268页

作者： Feihong Lin Zhongming yan Ping Wang Yu Wang Hongcheng Zhou Haoran Lu School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle Ministry of EducationChengdu 610031China China Academy of Launch Vehicle Technology Beijing 100076China

An ultrawideband reflectionless metamaterial absorber(MA)is proposed by replacing the metallic ground with the complementary split-ring resonator(CSRR)*** proposed MA exhibits-10 d b reflectivity spectrum from 1 GHz to 20 GHz,which maintains more than 90%absorption from 1.5 GHz to20 ***,it achieves angle stability for TE and TM polarization at oblique incident angles up to 40°and 65°,*** achieve broadband absorption spectrum,we have adopted a single-layer high-impedance surface(HIS)loaded with a double-layer magnetic material(MM)*** further realize the RCS reduction into a lower frequency range,we have employed the scattering cancellation technology into the traditional metallic ***,we have fabricated a sample exhibiting the 10 d b RCS reduction from 1 GHz to 20 GHz with a thickness of 10 *** and simulation results confirm that the proposed MA exhibits excellent comprehensive performance,making it suitable for many practical applications.

关键词： Metamaterial absorber(MA) Magnetic material(MM) High-impedance surface(HIS) Scattering cancellation technology Ultrawideband Wide-angular stable

beyond 1,4-addition of in-situ generated(aza-)quinone methides and indole imine methides

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Chinese Chemical Letters 2024年第7期35卷 35-53页

作者： yan-Li Li Zhi-Ming Li Kai-Kai Wang Xiao-Long He Medical College Xinxiang UniversityXinxiang 453000China School of Pharmacy Xinxiang UniversityXinxiang 453000China School of Food and bioengineering Xihua UniversityChengdu 610039China

The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and *** alcohols,aminobenzhydryl alcohols,and varied indolylmethanols served as most effective precursors for the in-situ generation of such reactive species under acid *** relevant propargylic alcohol has proven to be an elegant precursor to generate the propargylic-QMs and-IIMs via the acid promoted dehydration process,thus enabling diverse challenging remote activation to proceed conjugate1,6-and 1,***,the heteroarene has proven to be workable to transfer the LUMO of the p-QMs and 2-IIMs,thus inducing the remote nucleophilic dearomative *** conjugate additions of(aza-)p-QMs and varied IIMs has made significant contribution in the field of remote activation chemistry in past *** review summarizes the latest advances of the remote conjugate additions of the in-situ generated QMs and IIMs.

关键词： Conjugate addition QMs IIMs LUMO Remote activation Dearomative addition

Transition-Metal-Free Allylic Defluorination Cross-Electrophile Coupling Employing Rongalite

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Chinese Journal of Chemistry 2024年第12期42卷 1360-1366页

作者： Xiang-Long Chen Chun-yan Wu Dong-Sheng yang bo-Cheng Tang Huai-Yu Wang Zhi-Cheng Yu Anling Li yan-Dong Wu An-Xin Wu National Key Laboratory of Green Pesticide International Joint Research Center for Intelligent Biosensor Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhanHubei 430079China state Key Laboratory of Chemical biology and Drug Discovery Department of Applied Biology and Chemical Technology The HongKong Polytechnic UniversityKowloonHong Kong SARChina Department of Clinical Laboratory Center for Gene Diagnosisand Program of Clinical Laboratory MedicineZhongnan Hospital of Wuhan UniversityWuhanHubei 430062China

Comprehensive Summary The conversion of CF3-alkenes to gem-difluoroalkenes using reductive cross-coupling strategy has received much attention in recent years,however,the use of green and readily available reducing salt to mediate these reactions remains to be *** this work,a concise construction of gem-difluoroalkenes,which requires neither a catalyst nor a metal reducing agent,was ***,a safe and inexpensive industrial product,was employed as both a radical initiator and *** procedure was compatible with both linear and cyclic diaryliodonium salts,enabling a wide variety of substrates(>70 examples).The utility of this approach was demonstrated through gram-scale synthesis and efficient late-stage functionalizations of anti-inflammatory drugs.

关键词： Defluoroarylation Transition metal free gem-Difluoroalkenes Rongalite Single electron transfer C-C coupling Redox reactions Cross-coupling

Cooperative activation of sodium channels for downgrading the energy efficiency in neuronal information processing

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Chinese Physics b 2024年第5期33卷 758-763页

作者：严浩然颜家琦俞连春邵玉峰 School of Physical Science and Technology Lanzhou Center for Theoretical PhysicsLanzhou UniversityLanzhou 730000China Key Laboratory of Theoretical Physics of Gansu Province and Key Laboratory of Quantum Theory and Applications of MoELanzhou UniversityLanzhou 730000China Department of Neuroscience AnatomyHistologyand EmbryologyKey Laboratory of Preclinical Study for New Drugs of Gansu ProvinceSchool of Basic Medical SciencesLanzhou UniversityLanzhou 730000China

The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological *** raises the problem why neurons would favor independent over cooperative channel *** this study,we evaluate how cooperative activation of sodium channels affects the neuron’s information processing and energy *** of the stochastic Hodgkin–Huxley model with cooperative activation of sodium channels show that,while cooperative activation enhances neuronal information processing capacity,it greatly increases the neuron’s energy *** a result,cooperative activation of sodium channel degrades the energy efficiency for neuronal information *** discovery improves our understanding of the design principles for neural systems,and may provide insights into future designs of the neuromorphic computing devices as well as systematic understanding of pathological mechanisms for neural diseases.

关键词： energy efficiency ion channel noise action potential generation neuronal dynamics

MMAE-loaded PLGA nanomedicine with improved biosafety to achieve efficient antitumor treatment

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Journal of Innovative Optical Health Sciences 2024年第2期17卷 79-93页

作者： Changqiang Xie yan Wang Zhenzhen Cai Jianghai Du Zhengyu Chen Junjie Wang Xingzhou Peng State Key Laboratory of Digital Medical Engineering School of biomedical Engineering Hainan University Haikou 570228P.R.China Key Laboratory of biomedical Engineering of Hainan Province One Health Institute Hainan University Haikou 570228P.R.China Key Laboratory of Hainan Trauma and Disaster Rescue The First Affiliated Hospital of Hainan Medical University Hainan Medical University Haikou 571199P.R.China Engineering Research Center for Hainan bio.Smart Materials and bio-Medical Devices Key Laboratory of Emergency and Trauma Ministry of EducationKey Laboratory of Hainan Functional Materials and Molecular ImagingCollege of Emergency and Trauma Hainan Medical UniversityHaikou 571199P.R.China

Monomethyl auristatin E(MMAE)is a derivative of the marine peptide Dolastatin 10,which has therapeutic effects against various cancers according to its antimitotic activity in multiple clinical *** antibody drug conjugate(ADC)of MMAE is currently used in clinical ***,the safety issues of MMAE-based ADC,such as high drug toxicity and poor bioavailability,still exist when using it for anticancer therapy.A sustained release of drug delivery approach should be used to reduce toxicity and achieve sufficient anticancer ***,PLGA-b-PEG 2000 with excellent biocompatibility and slow degradation ability was adopted to construct MMAE-loaded nanoparticles for safe and effective *** sustained release effect and the immunogenic cell death(ICD)effect of PLGA-MMAE nanoparticles were assessed by in vitro *** PLGA-MMAE nanoparticles effectively accumulated in the tumor through the enhanced permeability and retention(EPR)effect,inducing cell apoptosis and causing a certain degree of immune *** sustained drug release of PLGA-MMAE improved the bioavailability and effectively reduced the toxicity and development of the tumor compared to the effect of free MMAE or ***,this study provides a safe and effective chemotherapeutic approach,as well as a simple and effective synthetic process for MMAE-based nanoparticles,improving their therapeutic efficacy and safety.

关键词： Monomethyl auristatin E poly(lactic-co-glycolic acid)nanoparticles sustained release chemotherapy immunogenic cell death