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sandwich structures with tapered tubes as core:A quasi-static investigation

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Defence Technology（防务技术） 2024年第3期33卷 447-462页

作者： Xinmei Xiang Dehua Shao Xin Zhang Umer Sharif Ngoc san Ha Li Xiang Jing Zhang Jiang Yi School of Civil engineering Guangzhou UniversityGuangzhouChina Department of Mechanics and Aerospace engineering Southern University of Science and TechnologyShenzhenGuangdongChina School of engineering Centre for Innovative Structures and MaterialsRMIT UniversityMelbourneAustralia China Southern Airlines Co. LtdShenzhen BranchShenzhen518000China

In this article,the experimental and finite element analysis is utilized to investigate the quasi-static compression features of sandwich constructions built with tapered tubes.3D printing technology was utilized to create the hollow centers of the tapering tubes,with and without *** results demonstrate that the energy absorption(eA)and specific energy absorption(SeA)of the single corrugated tapered tube sandwich are 51.6% and 19.8% higher,respectively,than those of the conical tube ***,the results demonstrate that energy absorbers can benefit from corrugation in order to increase their ***,the tapered corrugated tubes'resistance to oblique impacts was *** to a straight tube,the tapered tube is more resistant to oblique loads and has a lower initial peak crushing force(PCF),according to numerical *** conducting a parametric study,it was discovered that the energy absorption performance of the sandwich construction is significantly affected by the amplitude,number of corrugations,and wall *** and SeA of DTS with corrugation number of 8 increased by 17.4%and 29.6%,respectively,while PCF decreased by 9.2% compared to DTS with corrugation number of 10.

关键词： sandwich structure Corrugated tube Tapered tube Quasi-static energy absorption

Proposal for valleytronic materials:Ferrovalley metal and valley gapless semiconductor

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Frontiers of physics 2024年第2期19卷 131-139页

作者： san-Dong Guo Yu-Ling Tao Guangzhao Wang Shaobo Chen Dong Huang Yee Sin Ang School of electronic engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China Key Laboratory of extraordinary Bond engineering and Advanced Materials Technology of Chongqing School of Electronic Information EngineeringYangtze Normal UniversityChongqing 408100China College of electronic and Information engineering Anshun UniversityAnshun 561000China Science Mathematics and Technology(SMT)Singapore University of Technology and Design(SUTD)8 Somapah RoadSingapore 487372Singapore

Valleytronic materials can provide new degrees of freedom to future electronic *** this work,the concepts of the ferrovalley metal(FVM)and valley gapless semiconductor(VGS)are proposed,which can be achieved in valleytronic bilayer systems by electric field *** valleytronic bilayer systems,the interaction between out-of-plane ferroelectricity and A-type antiferromagnetism can induce layer-polarized anomalous valley Hall(LP-AVH)*** K and−K valleys of FVM are both metallic,and electron and hole carriers simultaneously *** the extreme case,the FVM can become VGS by analogizing spin gapless semiconductor(SGS).Moreover,it is proposed that the valley splitting enhancement and valley polarization reversal can be achieved by electric field engineering in valleytronic bilayer *** the bilayer RuBr_(2)as an example,our proposal is confirmed by the first-principle *** FVM and VGS can be achieved in bilayer RuBr_(2)by applying electric *** appropriate electric field range,increasing electric field can enhance valley splitting,and the valley polarization can be reversed by flipping electric field *** effectively tune valley properties by electric field in bilayer systems,the parent monolayer should possess out-of-plane magnetization,and have large valley *** results shed light on the possible role of electric field in tuning valleytronic bilayer systems,and provide a way to design the ferrovalley-related material by electric field.

关键词： valleytronics electric field bilayer

Aggregation-induced emission polymers via reversible-deactivation radical polymerization Special Collection:Distinguished Australian Researchers

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Aggregate

Aggregate 2024年第1期5卷 16-46页

作者： Nicholas Kai Shiang Teo Bo Fan Aditya Ardana san H.Thang School of Chemistry Monash UniversityClaytonVictoriaAustralia

Aggregation-induced emission(AIe)is a unique phenomenon whereby aggregation of molecules induces fluorescence emission as opposed to the more commonly known aggregation-caused quenching(ACQ).AIe has the potential to be utilized in the large-scale production of AIe-active polymeric materials because of their wide range of practical applications such as stimuli-responsive sensors,biological imaging agents,and drug delivery *** is evident from the increasing number of publications over the years since AIe was first *** addition,the evergrowing interest in this field has led many researchers around the world to develop new and creative methods in the design of monomers,initiators and crosslinkers,with the goal of broadening the scope and utility of AIe *** of the most promising approaches to the design and synthesis of AIe polymers is the use of the reversible-deactivation radical polymerization(RDRP)techniques,which enabled the production of well-controlled AIe materials that are often difficult to achieve by other *** this review,a summary of some recent works that utilize RDRP for AIe polymer design and synthesis is presented,including(i)the design of AIe-related monomers,initiators/crosslinkers;the achievements in preparation of AIe polymers using(ii)reversible addition–fragmentation chain transfer(RAFT)technique;(iii)atom transfer radical polymerization(ATRP)technique;(iv)other techniques such as Cu(0)-RDRP technique and nitroxide-mediated polymerization(NMP)technique;(v)the possible applications of these AIe polymers,and finally(vi)a summary/perspective and the future direction of AIe polymers.

关键词： aggregation-induced emission atom transfer radical polymerization nitroxide-mediated polymerization reversible addition–fragmentation chain transfer reversible-deactivation radical polymerization

Multi-environment BSA-seq using large F3 populations is able to achieve reliable QTL mapping with high power and resolution: An experimental demonstration in rice

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The Crop Journal 2024年第2期12卷 549-557页

作者： Yan Zheng ei ei Khine Khin Mar Thi ei ei Nyein Likun Huang Lihui Lin Xiaofang Xie Min Htay Wai Lin Khin Than Oo Myat Myat Moe san san Aye Weiren Wu College of Life Sciences Fujian Agriculture and Forestry UniversityFuzhou 350002FujianChina Fujian Provincial Key Laboratory of Crop Breeding by Design Fujian Agriculture and Forestry UniversityFuzhou 350002FujianChina Key Laboratory of Genetics Breeding and Multiple Utilization of CropsMinistry of EducationFujian Agriculture and Forestry UniversityFuzhou 350002FujianChina Department of Botany Mawlamyine UniversityMon StateMawlamyineMyanmar Department of Botany Dagon UniversityNorth DagonYangonMyanmar

Bulked-segregant analysis by deep sequencing(BSA-seq) is a widely used method for mapping QTL(quantitative trait loci) due to its simplicity, speed, cost-effectiveness, and efficiency. However, the ability of BSA-seq to detect QTL is often limited by inappropriate experimental designs, as evidenced by numerous practical studies. Most BSA-seq studies have utilized small to medium-sized populations, with F2populations being the most common choice. Nevertheless, theoretical studies have shown that using a large population with an appropriate pool size can significantly enhance the power and resolution of QTL detection in BSA-seq, with F_(3)populations offering notable advantages over F2populations. To provide an experimental demonstration, we tested the power of BSA-seq to identify QTL controlling days from sowing to heading(DTH) in a 7200-plant rice F_(3)population in two environments, with a pool size of approximately 500. each experiment identified 34 QTL, an order of magnitude greater than reported in most BSA-seq experiments, of which 23 were detected in both experiments, with 17 of these located near41 previously reported QTL and eight cloned genes known to control DTH in rice. These results indicate that QTL mapping by BSA-seq in large F_(3)populations and multi-environment experiments can achieve high power, resolution, and reliability.

关键词： BSA-seq QTL mapping Large F3 population Multi-environment experiment Cross-validation

Improving the Segmentation of Arabic Handwriting Using Ligature Detection Technique

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Computers, Materials & Continua 2024年第5期79卷 2015-2034页

作者： Husam Ahmad al Hamad Mohammad Shehab College of Computer Sciences and Informatics Amman Arab UniversityAmman11953Jordan

Recognizing handwritten characters remains a critical and formidable challenge within the realm of computervision. although considerable strides have been made in enhancing english handwritten character recognitionthrough various techniques, deciphering Arabic handwritten characters is particularly intricate. This complexityarises from the diverse array of writing styles among individuals, coupled with the various shapes that a singlecharacter can take when positioned differently within document images, rendering the task more perplexing. Inthis study, a novel segmentation method for Arabic handwritten scripts is suggested. This work aims to locatethe local minima of the vertical and diagonal word image densities to precisely identify the segmentation pointsbetween the cursive letters. The proposed method starts with pre-processing the word image without affectingits main features, then calculates the directions pixel density of the word image by scanning it vertically and fromangles 30° to 90° to count the pixel density fromall directions and address the problem of overlapping letters, whichis a commonly attitude in writing Arabic texts by many people. Local minima and thresholds are also determinedto identify the ideal segmentation area. The proposed technique is tested on samples obtained fromtwo datasets: Aself-curated image dataset and the IFN/eNIT dataset. The results demonstrate that the proposed method achievesa significant improvement in the proportions of cursive segmentation of 92.96% on our dataset, as well as 89.37%on the IFN/eNIT dataset.

关键词： Arabic handwritten segmentation image processing ligature detection technique intelligent recognition

Linear endoscopic ultrasound:Current uses and future perspectives in mediastinal examination

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World Journal of Gastroenterology 2024年第33期30卷 3803-3809页

作者： eyad Gadour Sarah al Ghamdi Bogdan Miutescu Hossam e Shaaban Zeinab Hassan Aymen almuhaidb Hussein H Okasha Department of Gastroenterology and Hepatology King Abdulaziz National Guard HospitalAhsa 36428Saudi Arabia Department of Internal Medicine Zamzam University CollegeSchool of MedicineKhartoum 11113Sudan Department of Medicine Division of GastroenterologyKing Abdulaziz UniversityJeddah 3646Saudi Arabia Department of Gastroenterology and Hepatology Victor Babes University of Medicine and PharmacyTimisoara 300041Romania Advanced Regional Research Center in Gastroenterology and Hepatology Victor Babes University of Medicine and PharmacyTimisoara 300041Romania Department of Internal Medicine and Gastroenterology NhtmriCairo 11796Egypt Department of Internal Medicine Stockport Hospitals NHS Foundation TrustManchester SK27JEUnited Kingdom Department of Gastroenterology King Faisal Specialist Hospital and Research CenterRiyadh 11211Saudi Arabia Department of Internal Medicine Division of Gastroenterology and HepatologyKasr Al-Aini School of MedicineCairo UniversityCairo 11562Egypt

This editorial elaborates on the current and future applications of linear endoscopic ultrasound(eUS),a substantial diagnostic and therapeutic modality for various anatomical *** scope of endosonographic assessment is broad and,among other factors,allows for the evaluation of the mediastinal anatomy and related pathologies,such as mediastinal lymphadenopathy and the staging of central malignant lung ***,eUS assessment has proven more accurate in detecting small lesions missed by standard imaging examinations,such as computed tomography or magnetic resonance *** focus on its current uses in the mediastinum,including lung and esophageal cancer staging,as well as evaluating mediastinal lymphadenopathy and submucosal *** editorial also explores future perspectives of eUS in mediastinal examination,including ultrasound-guided therapies,artificial intelligence integration,advancements in mediastinal modalities,and improved diagnostic approaches for various mediastinal lesions.

关键词： Linear endoscopic ultrasound Mediastinal examination Lung cancer Computed tomography Magnetic resonance imaging

High temperature deformation and recrystallization behavior of magnesium bicrystals with 90°<1010>and 90°<1120>tilt grain boundaries

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Journal of Magnesium and alloys 2024年第2期12卷 625-638页

作者： Kevin Bissa Talal al-Samman Dmitri A.Molodov Institute of Physical Metallurgy and Materials Physics RWTH Aachen University52056 AachenGermany International Research Organization for Advanced Science and Technology(IROAST) Kumamoto UniversityKumamoto 860-8555Japan

The deformation mechanisms and dynamic recrystallization(DRX)behavior of specifically grown bicrystals with a symmetric 90°and 90°tilt grain boundary,respectively,were investigated under deformation in plane strain compression at 200℃and 400℃.The microstructures were analyzed by panoramic optical microscopy and large-area electron backscatter diffraction(eBSD)orientation *** analysis employed a meticulous approach utilizing hundreds of individual,small eBSD maps with a small step size that were stitched together to provide comprehensive access to orientation and misorientation data on a macroscopic *** slip primarily governed the early stages of deformation at the two temperatures,and the resulting shear induced lattice rotation around the transverse direction(TD)of the *** existence of the grain boundary gave rise to dislocation pile-up in its vicinity,leading to much larger TD-lattice rotations within the boundary region compared to the *** increasing temperature,the deformation was generally more uniform towards the bulk due to enhanced dislocation mobility and more uniform stress *** recrystallization at 200℃was initiated in{1011}-compression twins at strains of 40%and *** 400℃,DRX consumed the entire grain boundary region and gradually replaced the deformed microstructure with progressing *** recrystallized grains displayed characteristic orientations,such that their c-axes were perpendicular to the TD and additionally scattered between 0°and 60°from the loading *** recrystallized grains displayed mutual rotations of up to 30°around the c-axes of the initial grains,forming a discernible basal fiber texture component,prominently visible in the{1120}pole *** is noteworthy that the deformation and DRX behaviors of the two analyzed bicrystals exhibited marginal variations in response to strain and deformation temperature.

关键词： elevated deformation temperatures Plain strain compression Magnesium bicrystals Panorama eBSD Dynamic Recrystallization

Storing Freshwater Versus Storing electricity in Power Systems with High Freshwater electric Demand

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Journal of Modern Power Systems and Clean energy 2024年第2期12卷 323-333页

作者： Mubarak J.al-Mubarak Antonio J.Conejo Department of electrical and Computer engineering The Ohio State UniversityColumbusOHUSA Department of electrical engineering Kuwait UniversityP.O.Box 5969Safat 13060Kuwait Department of Integrated Systems engineering and the Department of electrical and Computer engineering The Ohio State UniversityColumbusOH 43210USA Ieee

We consider a power system whose electric demand pertaining to freshwater production is high(high freshwater electric demand),as in the Middle east,and investigate the tradeoff of storing freshwater in tanks versus storing electricity in batteries at the day-ahead operation *** storing freshwater and storing electricity increase the actual electric demand at valley hours and decrease it at peak hours,which is generally beneficial in term of cost and ***,to what extent?We analyze this question considering three power systems with different generation-mix configurations,i.e.,a thermal-dominated mix,a renewable-dominated one,and a fully renewable *** generation-mix configurations are inspired by how power systems may evolve in different countries in the Middle *** production uncertainty is compactly modeled using chance *** draw conclusions on how both storage facilities(freshwater and electricity)complement each other to render an optimal operation of the power system.

关键词： Power system operation freshwater production and transportation coordination day-ahead scheduling

Role of Air Staging in a Batch-Type Fixed Bed Biomass Combustor under Constant Primary Air

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Journal of Thermal Science 2024年第1期33卷 284-299页

作者： Awais JUNeJO Yasir M.al-ABDeLI Jacobo PORTeIRO School of engineering Edith Cowan UniversityJoondalupWA 6027Australia CINTeCX Universidade de Vigo Grupo de Tecnoloxia Enerxetica(GTE)36310 VigoEspana

Staged combustion of biomass is the most suitable thermo-chemical conversion for achieving lower gaseous emissions and higher fuel conversion *** a staged fixed bed combustion of biomass,combustion air is supplied in two *** the first stage,primary air is provided below the fuel,whereas in the later stage,secondary air is supplied in the freeboard *** available literature on the effects of air staging(secondary air location) at a constant primary air flow rate on combustion characteristics in a batch-type fixed bed combustor is limited and hence warrants further *** study resolves the effect of air staging,by varying the location of secondary air in the freeboard at five secondary to total air ratios in a batch-type fixed bed *** are reported for the effects of these controlled parameters on fuel conversion rate,overall gaseous emissions(CO_(2),CO and NO_x) and temperature *** fuel used throughout was densified hardwood *** show that a primary freeboard length(distance between fuel bed top and secondary air injection) of200 mm has higher fuel conversion rates and temperatures as well as lower CO emissions,at a secondary to total air ratio of 0.75 as compared to primary freeboard length of 300 ***,NO_x emissions were found to be lower for a primary freeboard length of 300 mm as compared to 200 *** increase in secondary to total air ratio from 0.33 to 0.75 resulted in higher freeboard temperatures and lower CO as well as NO_x *** outcomes of this study will be helpful in the effective design of commercial scale biomass combustors for more efficient and environmentally friendly combustion.

关键词： fixed bed combustor biomass combustion air staging freeboard temperature burning rate gaseous emissions