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Review on heat-to-power conversion technologies for hypersonic vehicles

Chinese Journal of Aeronautics 2024年第5期37卷 148-179页

作者： Yinke QI xia.feng ma.peixue jia.g Yinhai ZHU Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Beijing Key Laboratory of CO_(2)Utilization and Reduction Technology Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

Hypersonic vehicles have enormous military and economic value,while their power and thermal protection demands will increase substantially with the rise in mach number and *** the tremendous high-quality heat on the vehicle surface and engine wall into electrical energy through heat-to-power technologies will not only play a role in thermal protection,but also supply power for the *** paper provides a comprehensive review of heat-to-power conversion technologies on hypersonic vehicles,including the indirect conversion of Brayton and Rankine cycles,direct conversion of thermoelectric materials,and combined *** the open Brayton cycle with hydrocarbon fuel as the working fluid,the Power-to-Weight Ratio(PWR)can achieve the highest,at around 1.8,due to the high PWR of the hydrocarbon fuel turbine and the few components of the ***,its work capacity is limited by the flow rate of the supplied *** closed Brayton cycle can maintain a relatively high PWR,ranging from 0.2 to 0.8,while achieving relatively high output power and conversion *** Rankine cycle has a higher PWR,its range is close to that of the closed Brayton cycle,peaking at about *** thermoelectric materials technology has a small power generation level,making it more suitable for scenarios with low power *** review provides a basis for selecting and developing heat-to-power conversion technologies on hypersonic vehicles.

关键词： Hypersonic vehicles Heat-to-power conversion Brayton cycle Rankine cycle Thermoelectric materials

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Decomposition of monazite in Bayan Obo rare earth ore by roasting of Na_(2)CO_(3)pellets

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Journal of Rare Earths 2024年第10期42卷 1969-1978页

作者： Ruifeng ma jianfei Li xiaowei Zhang Peijie jia Zhaogang Liu Jinxiu Wu Fushan feng Wenbin Xin Cllege of materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotouO14010China Key Laboratory of green Extraction and Eficient Utilization of Light Rare Earth Resources Ministry of EducationBaotouO14010China Key Laboratory of Rare Earth Wet Metallurgy and Light Rare Earth Applications of Inner Mongolia Autonomous Region BaotouO14010China

To resolve the issue of rotary kiln agglomeration during the sodium carbonate roasting of dolomite rare earth ore,this study introduces an oxidation-sodization pellet roasting method for decomposing mixed rare earth *** focus of this paper lies in understanding the bonding and roasting mechanism of sodium polyacrylate as a binder to dolomite ore and examining the process index of Na_(2)CO_(3)pellets roasting-acid leaching using X-ray diffraction(XRD),scanning ele ctron microscopy with energy dispersive spectroscopy(SEM-EDS),and zeta potential analysis,The results indicate that sodium polyacrylate facilitates the bonding of sodium carbonate to monazite via adsorption of positive and negative charges,and upon roasting at 750℃for 1.5 h to obtain rare earth *** conditions of a hydrochloric acid(HCl)concentration of 9 mol/L,a reaction for 60 min,a solid-to-liquid ratio(g:mL)of 1:5,and reaction temperature of 90℃,the leaching rates of rare earth elements and thorium(Th)reached maxima of 85.14%and 95.53%,*** process results in a yield of 47.61%for fluorine(F)and89.25%for phosphorus(P).This research forms a foundation for the sodium carbonate roasting decomposition of mixed rare earth concentrates.

关键词： Rare earths Pellets Decomposition Extraction Bayan Obo

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Multifunctional Film Assembled from N‑Doped Carbon Nanofiber with Co–N_(4)–O Single Atoms for Highly Efficient Electromagnetic Energy Attenuation

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Nano-Micro Letters 2024年第11期16卷 359-376页

作者： jia Xu Bei Li Zheng ma xiao Zhang Chunling Zhu feng Yan Piaoping Yang Yujin Chen College of materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001People’s Republic of China Key Laboratory of In‑Fiber Integrated Optics College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001People’s Republic of China

Single-atom materials have demonstrated attractive physicochemical ***,understanding the relationships between the coordination environment of single atoms and their properties at the atomic level remains a considerable ***,a facile waterassisted carbonization approach is developed to fabricate well-defined asymmetrically coordinated Co–N_(4)–O sites on biomass-derived carbon nanofiber(Co–N_(4)–O/NCF)for electromagnetic wave(EMW)*** such nanofiber,one atomically dispersed Co site is coordinated with four N atoms in the graphene basal plane and one oxygen atom in the axial ***-depth experimental and theoretical studies reveal that the axial Co–O coordination breaks the charge distribution symmetry in the planar porphyrin-like Co–N_(4) structure,leading to significantly enhanced dielectric polarization loss relevant to the planar Co–N_(4) ***,the film based on Co–N_(4)–O/NCF exhibits light weight,flexibility,excellent mechanical properties,great thermal insulating feature,and excellent EMW absorption with a reflection loss of−45.82 dB along with an effective absorption bandwidth of 4.8 *** findings of this work offer insight into the relationships between the single-atom coordination environment and the dielectric performance,and the proposed strategy can be extended toward the engineering of asymmetrically coordinated single atoms for various applications.

关键词： Co single atoms Asymmetric coordination structure Axial oxygen coordination Electromagnetic wave absorption Multifunctional film

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MOF‐derived 1D/3D N‐doped porous carbon for spatially confined electrochemical CO2 reduction to adjustable syngas

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Carbon Energy 2024年第8期6卷 1-13页

作者： Wei Zhang Hui Li Daming feng Chenglin Wu Chenghua Sun Baohua jia Xue Liu Tianyi ma Key Laboratory for green Synthesis and Preparative Chemistry of Advanced materials Institute of Clean Energy ChemistryCollege of ChemistryLiaoning UniversityShenyangLiaoningChina School of Science RMIT UniversityMelbourneVictoriaAustralia School of Pharmaceutical and Chemical Engineering Taizhou UniversityTaizhouZhejiangChina Department of Chemistry and Biotechnology Swinburne University of TechnologyHawthornVictoriaAustralia

Electrochemical reduction of CO_(2)to syngas(CO and H_(2))offers an efficient way to mitigate carbon emissions and store intermittent renewable energy in ***,the hierarchical one‐dimensional/three‐dimensional nitrogen‐doped porous carbon(1D/3D NPC)is prepared by carbonizing the composite of Zn‐MOF‐74 crystals in situ grown on a commercial melamine sponge(MS),for electrochemical CO_(2)reduction reaction(CO_(2)RR).The 1D/3D NPC exhibits a high CO/H_(2)ratio(5.06)and CO yield(31 mmol g^(−1)h^(−1))at−0.55 V,which are 13.7 times and 21.4 times those of 1D porous carbon(derived from Zn‐MOF‐74)and N‐doped carbon(carbonized by MS),*** is attributed to the unique spatial environment of 1D/3D NPC,which increases the adsorption capacity of CO_(2)and promotes electron transfer from the 3D N‐doped carbon framework to 1D carbon,improving the reaction kinetics of CO_(2)*** results and charge density difference plots indicate that the active site of CO_(2)RR is the positively charged carbon atom adjacent to graphitic N on 1D carbon and the active site of HER is the pyridinic N on 1D *** presence of pyridinic N and pyrrolic N reduces the number of electron transfer,decreasing the reaction kinetics and the activity of CO_(2)*** CO/H_(2)ratio is related to the distribution of N species and the specific surface area,which are determined by the degree of spatial confinement *** CO/H_(2)ratios can be regulated by adjusting the carbonization temperature to adjust the degree of spatial confinement *** the low cost of feedstock and easy strategy,1D/3D NPC catalysts have great potential for industrial application.

关键词： electrochemical CO_(2)reduction reaction melamine sponge metal‐organic frameworks porous carbon syngas

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Deployment analysis of composite thin-walled lenticular tubes with effect of storage time and temperature

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Chinese Journal of Aeronautics 2024年第1期37卷 162-172页

作者： Jinfeng DENg Ning AN Qilong jia xiaofei ma School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China State Key Laboratory for Strength and Vibration of Mechanical Structures School of AerospaceXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Xi’an Institute of Space Radio Technology Xi’an 710100China

Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable *** CTLT is initially flattened and coiled around a central hub for storage before launch,during which elastic energy is stored as deformation energy,allowing it to be self-deployed on demand for use in *** work presents a comprehensive investigation into the coiling,storage and deployment behaviors of CTLT that wraps around a central hub.A nonlinear explicit dynamic finite element model was developed with both deformable CTLT and rigidbodies mechanisms including the central hub and guide rollers,as well as the complex interactions among *** coiling mechanics characteristics such as stored strain energy and rotational moment were presented and validated against experimental data in the ***,the dynamic deployment behaviors were analyzed in terms of two different deployment methods,namely,controlled deployment and free *** effect of material property change during storage was also discussed through numerical experiments.

关键词： Composite deployable structures Deployment dynamics Finite element method Stress relaxation Thin-walled booms

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genome-wide CRISPR screening reveals key genes and pathways associated with 20-hydroxyecdysone signal transduction in the silkworm(Bombyx mori)

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Insect Science 2024年第1期31卷 47-58页

作者： Hao Sun Jingya Chen Ruolin Wang Dan Liu Na Zhang Tong Zhang Ling jia Sanyuan ma Qingyou xia State Key Laboratory of Silkworm genome Biology Southwest UniversityChongqingChina Biological Science Research Center Southwest UniversityChongqingChina

Metamorphosis is a complex developmental process involving multiple pathways and a large number of genes that are regulated by juvenile hormone(JH)and 20-hydroxyecdysone(20E).Despite important progress in understanding various aspects of silkworm biology,the hormone signaling pathway in the silkworm remains poorly ***-wide screening using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-based libraries has recently emerged as a novel method for analyzing genome function,enabling further research into essential genes,drug targets,and virus-host ***,we constructed a genome-wide CRISPR/Cas9-based library of the silkworm(Bombyx mori)and successfully revealed the genes involved in biotic or abiotic stress factor *** this study,we used our silkworm CRISPR library and large-scale genome-wide screening to analyze the key genes in the silkworm 20E signaling pathway and their mechanisms of *** annotation showed that 20E regulates key proteins in processes that mainly occur in the cytoplasm and *** enrichment analysis showed that 20E can activate phosphorylation and may affect innate immunity,interfere with intracellular nutrition and energy metabolism,and eventually cause cell *** screening results were experimentally validated by generating cells with knockout alleles of the relevant genes,which had increased tolerance to *** findings provide a panoramic overview of signaling in response to 20E in the silkworm,underscoring the utility of genome-wide CRISPR mutant libraries in deciphering hormone signaling pathways and the mechanisms that regulate metamorphosis in insects.

关键词： CRISPR/Cas9 CRISPR library screening ecdysone 20E signal transduction silkworm whole genome editing

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DNA Methylation Variation Is Identified in Monozygotic Twins Discordant for Congenital Heart Diseases

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Congenital Heart Disease 2024年第2期19卷 247-256页

作者： Shuliang xia Huikang Tao Shixin Su Xinxin Chen Li ma jianru Li Bei gao Xumei Liu Lei Pi Jinqing feng fengxiang Li jia Li Zhiwei Zhang guangdong Provincial People’s Hospital Southern Medical UniversityGuangzhou510100China Department of Cardiovascular Surgery Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangdong Provincial Clinical Research Center for Child HealthGuangzhou510623China Department of Pediatric Cardiology Guangdong Cardiovascular InstituteGuangdong Provincial Key Laboratory of South China Structural Heart DiseaseGuangzhou510100China Clinical Physiology Laboratory Institute of PediatricsGuangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangdong Provincial Key Laboratory of Research in Structural Birth Defect DiseaseGuangzhou510623China Department of Echocardiogram Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangdong Provincial Clinical Research Center for Child HealthGuangzhou510623China Department of Pediatrics Washington University School of MedicineSt.LouisMO63130USA Clinical Biological Resource Bank of guangzhou Women and Children’s Medical Center Guangzhou Medical UniversityGuangzhou510623China

Aims:Multiple genes and environmental factors are known to be involved in congenital heart disease(CHD),but epigenetic variation has received little ***(MZ)twins with CHD provide a unique model for exploring this *** order to investigate the potential role of Deoxyribonucleic Acid(DNA)methyla-tion in CHD pathogenesis,the present study examined DNA methylation variation in MZ twins discordant for CHD,especially ventricular septal defect(VSD).Methods and Results:Using genome-wide DNA methylation profiles,we identified 4004 differentially methylated regions(DMRs)in 18 MZ twin pairs discordant for CHD,and 2826 genes were *** Ontology(gO)and Kyoto Encyclopedia of genes and genomes(KEgg)analysis revealed a list of CHD-associated *** further investigate the role of DNA methylation in VSD,data from 7 pairs of MZ twins with VSD were *** identified 1614 DMRs corresponding to 1443 genes associated with arrhythmogenic right ventricular cardiomyopathy,cyclic guanosine monopho-sphate-protein kinase g(cgMP-PKg)signaling pathway by KEgg analysis,and cell-cell adhesion,calcium ion transmembrane transport by gO analysis.A proportion of DMR-associated genes were involved in calcium signaling *** methylation changes of calcium signaling genes might be related to VSD ***:CHD is associated with differential DNA methylation in MZ *** may be etiologically linked to DNA methylation,and methylation of calcium signaling genes may be involved in the development of VSD.

关键词： Congenital heart disease monozygotic twins methylation modification epigenetics

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Diversification of interfaces triggered hydrogen storage properties enhancement

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Rare Metals 2024年第5期43卷 2324-2330页

作者： jia-Xin Zhang Xin Ding Rui-Run Chen xiang-feng ma Wen-Chao Cao Yong Zhang Jing-Jie guo National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

Dual effects of grain refinement and alloying are achieved and the mechanism of"diverse interfaces reinforcement"for hydrogen storage Mg alloys is first *** interface reinforced Mg-Y-Zn-Al alloy for hydrogen storage is *** work figures out that the adventurous Al-rich phase exhibits an ordered face-centered cubic(FCC)structure with composition of(31±2)at%Y-(28±1)at%Zn-(41±3)at%Al,i.e.,Y_(3)Zn_(3)Al_(4),and an incoherent interface between Y3Zn3Al4phase and Mg substrate is observed.

关键词： hydrogen alloying alloy

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Extraction,chemical components,bioactive functions and adulteration identification of walnut oils:A review

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grain & Oil Science and Technology 2024年第1期7卷 30-41页

作者： Yuan gao jia Hu xia Su Qi Li Caihong Su Yongling Li gaiqin ma Siyu Zhang Xiuzhu Yu Engineering Research Center of grain and Oil Functionalized Processing College of Food Science and EngineeringNorthwest A&F UniversityShaanxi 712100China Animal Products and Animal Medicine Feed Quality Inspection Center Hebei 050041China

Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible *** are various extraction methods for walnut oil,including traditional(pressing,solvent-and enzymeassisted extraction)and novel methods(microwave,ultrasound,supercritical CO_(2),subcritical and other extraction technologies).Walnut oil is rich in nutrients,including phytosterols,tocopherols,polyphenols,squalene and *** provides many health benefits,such as antioxidant,antitumor,anti-inflammatory,antidiabetic and lipid metabolism-related *** addition,the authentication of walnut oil has received much research *** present review provides detailed research on walnut oil extraction,composition,health benefits and adulteration identification *** path toward further walnut oil improvement in the context of the market value of walnut oil is also discussed.

关键词： Extraction technology Chemical composition Bioactive Authentication

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Requirements ranking based on crowd-sourcing high-end product USs

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Journal of Systems Engineering and Electronics 2024年第1期35卷 94-104页

作者： ma Yufeng DOU Yajie XU xiangqian jia Qingyang TAN Yuejin College of Systems Engineering National University of Defense TechnologyChangsha 410003China

Based on the characteristics of high-end products,crowd-sourcing user stories can be seen as an effective means of gathering requirements,involving a large user base and generating a substantial amount of unstructured *** key challenge lies in transforming abstract user needs into specific ones,requiring integration and ***,we propose a topic mining-based approach to categorize,summarize,and rank product requirements from user ***,after determining the number of story categories based on py LDAvis,we initially classify“I want to”phrases within user ***,classic topic models are applied to each category to generate their names,defining each post-classification user story category as a ***,a weighted ranking function is devised to calculate the importance of each ***,we validate the effectiveness and feasibility of the proposed method using 2966 crowd-sourced user stories related to smart home systems.

关键词： high-end product complex system crowd-sourcing user stories topic mining requirements ranking

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