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An Inductor Model for Analyzing the Performance of Printed Meander Line Antennas in Smart Structures

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Journal of Electromagnetic Analysis and Applications 2014年第9期6卷 244-252页

作者： shih-ming yang Chih-Hsin Huang Department of Aeronautics and Astronautics National Cheng Kung University Taiwan

Meander line antenna has been considered desirable on flight vehicles to reduce drag and minimize aerodynamic disturbance;however, the antenna design and performance analysis have made mostly by trial-and-error. An inductor model by simulating the meander line sections as electrical inductors and the interconnecting radiation elements as a quasi-monopole antenna is developed to analyze the antenna performance. Experimental verifications of the printed meander line antennas embedded in composite laminated substrates show that the inductor model is effective to design and analyze. Of the 4 antennas tested, the discrepancy of resonant frequency in simulation and experiment is within 4.6%.

关键词： Inductor Model Meander Line Antenna Smart Structure

Tunable Thermo-Responsive Shape Memory Materials Enabled by Poly(ε-caprolactone)-Poly(2-vinyl)ethylene Glycol Copolymers via Facile Thiol-Ene Photo-Crosslink

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Chinese Journal of Polymer Science 2025年第2期43卷 278-288页

作者： ming-Hang Wang Fan yang Yong-Jian Zhang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative Moleculesand School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai200240China Sichuan Research Institute Shanghai Jiao Tong UniversityChengdu610042China

Control crosslink network and chain connectivity are essential to develop shape memory polymers(SMPs)with high shape memory capabilities,adjustable response temperature,and satisfying mechanistical *** this study,novel poly(ε-caprolactone)(PCL)-poly(2-vinyl)ethylene glycol(PVEG)copolymers bearing multi-pendant vinyl groups is synthesized by branched-selective allylic etherification polymerization of vinylethylene carbonate(VEC)with linear and tetra-arm PCLs under a synergistic catalysis of palladium complex and boron *** thiol-ene photo-click reaction of PCL-PVEG copolymers with multifunctional thiols can rapidly access a serious crosslinked SMPs with high shape memory *** thermal properties,mechanical properties and response temperature of the obtained SMPs are tunable by the variation of PCL prepolymers,vinyl contents and functionality of ***,high elastic modulus in the rubbery plateau region can be maintained effectively owing to high-density topological networks of the PCL *** addition,the utility of the present SMPs is further demonstrated by the post-functionalization via thiol-ene photo-click chemistry.

关键词： Shape memory polymers Polycaprolactone Thiol-ene photo-crosslink Controlled crosslinking density Tunable response temperature

Causes of Winter Persistent Extreme Cold Events in Northeastern China

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Advances in Atmospheric Sciences 2025年第4期42卷 780-793页

作者： ming yang Qingjiu GAO Tim LI State Key Laboratory of Climate System Prediction and Risk Management/Key Laboratory of Meteorological Disaster Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China Department of Atmospheric Sciences University of Hawaii at ManoaHonoluluHI 96822USA

Persistent(5-day or longer)extreme cold events(ECEs)over northeastern China during the boreal winter of 1979–2020 are investigated using daily minimum temperature(Tmin)from the China Meteorological Data *** extreme cooling area and intensity indices associated with the ECEs exhibit a dominant 10–40-day periodicity,indicating a close link with atmospheric intraseasonal oscillations(ISOs).The ECEs are categorized into W-and *** the former,the low-frequency cooling associated with the ISO first penetrates into the western boundary of the northeastern China domain and later occupies the entire domain at its peak *** upper-tropospheric circulation associated with this type is characterized by a northwest–southeast-oriented Rossby wave train,expanding from the Ural Mountains to the western Pacific *** the latter,the cooling invades the northern boundary first and then penetrates into the entire *** upper tropospheric precursory signal associated with this type is a zonally oriented negative geopotential height anomaly,which slowly moves southward.A downward-propagating signal is observed in the stratospheric potential vorticity field prior to the peak cooling,implying a possible stratospheric *** addition to the W-and N-types,ECEs can also occur in a localized region near either at the northern or southern boundary of the domain.

关键词： extreme cold events low-frequency ISO mode Rossby wave train composite analysis downward propagation potential vorticity

Enhancement of weathered crust elution-deposited rare earth ores leaching process with PQ-10 addition

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Journal of Rare Earths 2025年第1期43卷 180-190,I0007页

作者： Aoyang Sha Huifang yang Zhengyan He Zhigao Xu Chenjie Wu ming Wu Ru'an Chi Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education Key Laboratory of Resources Conversion and Pollution Control of the State Ethnic Affairs Commission&Hubei Key Laboratory of Catalysis and Materials ScienceCollege of Resources and Environmental ScienceSouth-Central Minzu UniversityWuhan430074China Key Laboratory for Green Chemical Process of Ministry of Education School of Resources&Safety EngineeringWuhan Institute of TechnologyWuhan 430073China

To solve the problems of the long development period,low mass transfer efficiency and high impurity conte nt in the in-situ leaching process of weathe red crust elution-deposited rare earth ores(WCE-DREO),cationic hydroxyethyl cellulose(PQ-10)was composited with conventional leaching agent ammonium sulfate((NH_(4))_(2)SO_(4))to form a novel composite leaching *** effects of PQ-10 concentration,leaching temperature and leaching flow rate of the composite leaching agent on the leaching kinetics and mass transfer processes of rare earth(RE)and aluminum(Al)were *** to the single leaching agent(NH_(4))_(2)SO_(4),the composite leaching agent(2 wt%(NH_(4))_(2)SO_(4)+0.02 wt%PQ-10)can reduce the RE leaching equilibrium time from 465 to 130 min and increase the RE leaching efficiency and decrease the Al leaching *** also facilitates the leaching process of WCE-DREO by increasing the peak concentrations of RE and Al,reducing the theoretical tower plate height(HETP)and improving the leaching mass transfer *** is indicated that PQ-10 can promote the leaching of *** leaching process of the composite leaching system conforms to the diffusion kinetic control *** the PQ-10 concentration is in the range of 0.005 wt%-0.020 wt%,the reaction orders of RE and Al are 0.73 and 0.54,respectively,which shows a positive effect on the leaching velocity;when the PQ-10 concentration is in the range of 0.030 wt%-0.060 wt%,the reaction orders of RE and Al are-1.16 and-0.75,respectively,which show a negative effect on the leaching *** the range of 10-50℃,the apparent activation energies of RE and Al are 15.02 and 17.31 kJ/mol,respectively,and the higher the leaching temperature,the smaller the HETP and the higher the leaching velocity and mass transfer *** increase in leaching flow rate contributes to the increase in the longitudinal diffusion velocity of the leaching agent within WCE-DREO,causing a shorter time for RE

关键词： Cationic hydroxyethyl cellulose Weathered crust elution-deposited rare earthores Leaching Novel compositeagent

维普期刊数据库

Subsection cooling system of hot rolling silicon steel and its industrial application

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Journal of Iron and Steel Research International 2025年第1期32卷 159-170页

作者： Qiu-na Wang Ji-quan Sun Li-po yang Hai-shen Wang Li-jie Dong Jie-ming Li Zhen-yang Zhi Yan-wen Bi National Engineering Research Center of Flat Rolling Equipment University of Science and Technology BeijingBeijing100083China Hot Rolling Department of Qian’an Iron and Steel Corporation Shougang Company LimitedTangshan064404HebeiChina National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

An online subsection cooling method for hot rolling silicon steel was designed to achieve local adjustment of transverse roll ***,it was able to meet the requirements of edge drop of the strip by using the features of online thermal ***,after the new subsection spray beam was installed at the exit of mill,the special local cooling rules were analyzed for altering the thermal crown of roll according to rolling process ***,the dynamic impact of subsection cooling on the local thermal crown could just be obtained according to the measured ***,the heat transfer coefficient was determined by different subsection cooling curves under varied rolling ***,the rolling rhythm and variable conditions were important dynamic factors of transient roll temperature in practical rolling ***,real-time calculation and presetting of the thermal crown were carried out to maximize special requirements of load roll gap on local strip *** this new method,the transient temperature and the thermal crown of roll could be quantitatively controlled *** the practical results showed that the predicted temperature was able to match the measured value by more than 95%.Meanwhile,the adjustable range of thermal crown increased by more than 2.5 ***,the qualification rate of strip edge crown has increased from the original 30%to over 70%.

关键词： Subsection cooling Thermal roll crown Multi-parameter coupling Hot rolling Silicon steel

Microwave irradiation-induced deterioration of rock mechanical properties and implications for mechanized hard rock excavation

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Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 275-290页

作者： Zheng yang ming Tao Muhammad Burhan Memon Dengdeng Zhuang Yan Zhao School of Resources and Safety Engineering Central South UniversityChangshaChina

In this study,a novel microwave-water cooling-assisted mechanical rock breakage method was proposed to address the issues of severe tool wear at elevated temperatures,poor rock microwave absorption,and excessive microwave energy *** investigation object was sandstone,which was irradiated at 4 kW microwave power for 60 s,180 s,300 s,and 420 s,followed by air and water ***,uniaxial compression,Brazilian tension,and fracture tests were *** evolution of damage in sandstone was measured using active and passive nondestructive acoustic detection *** roughness of the fracture surfaces of the specimens was quantified using the box-counting *** damage mechanisms of microwave heating and water cooling on sandstone were discussed from both macroscopic and microscopic *** experimental results demonstrated that as the duration of the microwave irradiation increased,the P-wave velocity,uniaxial compressive strength(UCS),elastic modulus(E),tensile strength,and fracture toughness of sandstone exhibited various degrees of weakness and were further weakened by water ***,an increase in the microwave irradiation duration enhanced the damaging effect of water *** P-wave velocity of the sandstone was proportional to the mechanical *** heating and water cooling weakened the brittleness of the sandstone to a certain *** fractal dimension of the fracture surface was correlated with the duration of microwave heating,and the water-cooling treatment resulted in a rougher fracture *** analysis of the instantaneous cutting rate revealed that water cooling can substantially enhance the efficiency of microwave-assisted rock breakage.

关键词： Hard rock breakage Microwave irradiation Water cooling Acoustic testing Fractal dimension Instantaneous cutting rate

Innovations and prospects of the tetrahedral constellation gravitational wave observatory

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Science China(Physics,Mechanics & Astronomy) 2025年第2期Mechanics & Astronomy) .卷 199-200页

作者： Zhi-ming Cai Zhong-Guang yang Innovation Academy for Microsatellites Chinese Academy of Sciences

Gravitational wave astronomy has opened a new window to the universe, allowing us to explore cosmic phenomena with unprecedented precision. Current detectors like LIGO [1],Virgo [1], KAGRA [1], LISA [2], Taiji [3], and Tian Qin [3] have made significant strides in gravitational wave ***, the demand for more sensitive and comprehensive detection capabilities continues to grow.

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The fourth exon confers antagonistic activity of OsMFT1 and OsMFT2 in rice pre-harvest sprouting

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Crop Journal 2025年第1期13卷 135-144页

作者： Zhang, Jialing Liu, Fei Kuang, yang Luo, ming Chu, Chengcai Xu, Fan College of Agronomy and Biotechnology Southwest University Chongqing 400715 China Guangdong Laboratory for Lingnan Modern Agriculture State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of Agriculture South China Agricultural University Guangdong Guangzhou 510642 China

Pre-harvest sprouting (PHS) describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops. PHS could seriously decrease grain yield and quality, which makes it a major constraint to cereal production worldwide. A number of PHS-associated genes in cereals have been reported;however, the molecular mechanisms underlying PHS remain largely elusive. Here, we report a CRISPR-Cas9 mutant with severe PHS in a paddy field. The mutated gene OsMFT2 encodes a phosphatidylethanolamine-binding protein (PEBP). Intriguingly, the OsMFT1, in the same PEBP family, had the opposite effect in controlling rice PHS as does OsMFT2. Germination tests of seeds of chimeric protein-expressing plants revealed that the fourth exon conferred the antagonistic activity of OsMFT1 and OsMFT2 in rice PHS. Additionally, two lines of these plants showed elevated grain numbers per panicle, implying that chimeric protein has potential to significantly increase yield. Moreover, transcriptome analysis and genetic studies indicated that OsMFT1 and OsMFT2 performed opposing functions in rice PHS owing to three co-regulated genes that being contrastingly affected by OsMFT1 and OsMFT2. Overall, it seemed that the proper combination of PEBP family members could obtain optimal PHS resistance and high yield. © 2025 Crop Science Society of China and Institute of Crop Science, CAAS

关键词： MFT PEBP Pre-harvest sprouting Rice

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