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Polarity-controllable magnetic skyrmion filter
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作者 Xiao-Lin Ai Hui-Ting Li +4 位作者 Xue-Feng Zhang Chang-Feng Li Je-Ho Shim Xiao-Ping Ma Hong-Guang Piao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期400-404,共5页
The skyrmion generator is one of the indispensable components for the future functional skyrmion devices,but the process of generating skyrmion cannot avoid mixing with other magnetic textures,such as skyrmionium and ... The skyrmion generator is one of the indispensable components for the future functional skyrmion devices,but the process of generating skyrmion cannot avoid mixing with other magnetic textures,such as skyrmionium and nested skyrmion bags.These mixed magnetic textures will inevitably lead to the blockage of skyrmion transport and even the distortion of data information.Therefore,the design of an efficient skyrmion filter is of great significance for the development of skyrmion-based spintronic devices.In this work,a skyrmion filter scheme is proposed,and the high-efficiency filtering function is demonstrated by micromagnetic simulations.The results show that the filtering effect of the scheme depends on the structure geometry and the spin current density that drives the skyrmion.Based on this scheme,the polarity of the filtered skyrmion can be controlled by switching the magnetization state at the output end,and the“cloning”of the skyrmion can be realized by geometric optimization of the structure.We believe that in the near future,the skyrmion filter will become one of the important components of skyrmion-based spintronic devices in the future. 展开更多
关键词 SPINTRONICS SKYRMIONS skyrmion filter skyrmion polarity skyrmion clone
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Effect of annealing on the electrical performance of N-polarity GaN Schottky barrier diodes
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作者 Nuo Xu Gaoqiang Deng +6 位作者 Haotian Ma Shixu Yang Yunfei Niu Jiaqi Yu Yusen Wang Jingkai Zhao Yuantao Zhang 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期48-55,共8页
A nitrogen-polarity(N-polarity)GaN-based high electron mobility transistor(HEMT)shows great potential for high-fre-quency solid-state power amplifier applications because its two-dimensional electron gas(2DEG)density ... A nitrogen-polarity(N-polarity)GaN-based high electron mobility transistor(HEMT)shows great potential for high-fre-quency solid-state power amplifier applications because its two-dimensional electron gas(2DEG)density and mobility are mini-mally affected by device scaling.However,the Schottky barrier height(SBH)of N-polarity GaN is low.This leads to a large gate leakage in N-polarity GaN-based HEMTs.In this work,we investigate the effect of annealing on the electrical characteristics of N-polarity GaN-based Schottky barrier diodes(SBDs)with Ni/Au electrodes.Our results show that the annealing time and tem-perature have a large influence on the electrical properties of N-polarity GaN SBDs.Compared to the N-polarity SBD without annealing,the SBH and rectification ratio at±5 V of the SBD are increased from 0.51 eV and 30 to 0.77 eV and 7700,respec-tively,and the ideal factor of the SBD is decreased from 1.66 to 1.54 after an optimized annealing process.Our analysis results suggest that the improvement of the electrical properties of SBDs after annealing is mainly due to the reduction of the inter-face state density between Schottky contact metals and N-polarity GaN and the increase of barrier height for the electron emis-sion from the trap state at low reverse bias. 展开更多
关键词 nitrogen polarity GAN Schottky barrier diodes ANNEALING interface state
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Gene expression,transcription factor binding and histone modification predict leaf adaxial-abaxial polarity related genes
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作者 Wei Sun Zhicheng Zhang +2 位作者 Guusje Bonnema Xiaowu Wang Aalt Dirk Jan van Dijk 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第4期971-982,共12页
Leaf adaxial-abaxial(ad-abaxial)polarity is crucial for leaf morphology and function,but the genetic machinery governing this process remains unclear.To uncover critical genes involved in leaf ad-abaxial patterning,we... Leaf adaxial-abaxial(ad-abaxial)polarity is crucial for leaf morphology and function,but the genetic machinery governing this process remains unclear.To uncover critical genes involved in leaf ad-abaxial patterning,we applied a combination of in silico prediction using machine learning(ML)and experimental analysis.A Random Forest model was trained using genes known to influence ad-abaxial polarity as ground truth.Gene expression data from various tissues and conditions as well as promoter regulation data derived from transcription factor chromatin immunoprecipitation sequencing(ChIP-seq)was used as input,enabling the prediction of novel ad-abaxial polarity-related genes and additional transcription factors.Parallel to this,available and newly-obtained transcriptome data enabled us to identify genes differentially expressed across leaf ad-abaxial sides.Based on these analyses,we obtained a set of 111 novel genes which are involved in leaf ad-abaxial specialization.To explore implications for vegetable crop breeding,we examined the conservation of expression patterns between Arabidopsis and Brassica rapa using single-cell transcriptomics.The results demonstrated the utility of our computational approach for predicting candidate genes in crop species.Our findings expand the understanding of the genetic networks governing leaf ad-abaxial differentiation in agriculturally important vegetables,enhancing comprehension of natural variation impacting leaf morphology and development,with demonstrable breeding applications. 展开更多
关键词 Machine learning Leaf polarity Arabidopsis thaliana Brassica rapa Transcription factor
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Modulating the Electrolyte Inner Solvation Structure via Low Polarity Co-solvent for Low-Temperature Aqueous Zinc-Ion Batteries
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作者 Yongchao Kang Feng Zhang +6 位作者 Houzhen Li Wangran Wei Huitong Dong Hao Chen Yuanhua Sang Hong Liu Shuhua Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第5期104-113,共10页
Aqueous zinc-ion batteries are regarded as the promising candidates for large-scale energy storage systems owing to low cost and high safety;however,their applications are restricted by their poor low-temperature perf... Aqueous zinc-ion batteries are regarded as the promising candidates for large-scale energy storage systems owing to low cost and high safety;however,their applications are restricted by their poor low-temperature performance.Herein,a low-temperature electrolyte for low-temperature aqueous zinc-ion batteries is designed by introducing low-polarity diglyme into an aqueous solution of Zn(ClO_(4))_(2).The diglyme disrupts the hydrogenbonding network of water and lowers the freezing point of the electrolyte to-105℃.The designed electrolyte achieves ionic conductivity up to16.18 mS cm^(-1)at-45℃.The diglyme and ClO_(4)^(-)reconfigure the solvated structure of Zn^(2+),which is more favorable for the desolvation of Zn^(2+)at low temperatures.In addition,the diglyme effectively suppresses the dendrites,hydrogen evolution reaction,and by-products of the zinc anode,improving the cycle stability of the battery.At-20℃,a Zn‖Zn symmetrical cell is cycled for 5200 h at 1 mA cm^(-2)and 1 mA h cm^(-2),and a Zn‖polyaniline battery achieves an ultra-long cycle life of 10000 times.This study sheds light on the future design of electrolytes with high ionic conductivity and easy desolvation at low temperatures for rechargeable batteries. 展开更多
关键词 aqueous zinc-ion batteries high performance inner solvation structure low polarity co-solvent low-temperature electrolyte
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CXCL9:SPP1 macrophage polarity identifies a network of cellular programs that control human cancers 被引量:1
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作者 Ruben Bill 《四川生理科学杂志》 2023年第8期1451-1451,共1页
Tumor microenvironments(TMEs)influence cancer progression but are complex and often differ between patients.Considering that microenvironment variations may reveal rules governing intratumoral cellular programs and di... Tumor microenvironments(TMEs)influence cancer progression but are complex and often differ between patients.Considering that microenvironment variations may reveal rules governing intratumoral cellular programs and disease outcome,we focused on tumor-to-tumor variation to examine 52 head and neck squamous cell carcinomas.We found that macrophage polarity-defined by CXCL9 and SPP1(CS)expression but not by conventional M1 and M2 markers-had a noticeably strong prognostic association.CS macrophage polarity also identified a highly coordinated network of either pro-or antitumor variables,which involved each tumor-associated cell type and was spatially organized.We extended these findings to other cancer indications.Overall,these results suggest that,despite their complexity,TMEs coordinate coherent responses that control human cancers and for which CS macrophage polarity is a relevant yet simple variable. 展开更多
关键词 CXCL9 MACROPHAGE polarity
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Enhanced Sentiment Analysis Algorithms for Multi-Weight Polarity Selection on Twitter Dataset
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作者 Ayman Mohamed Mostafa 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期1015-1034,共20页
Sentiment analysis is based on the orientation of user attitudes and satisfaction towards services and subjects.Different methods and techniques have been introduced to analyze sentiments for obtaining high accuracy.T... Sentiment analysis is based on the orientation of user attitudes and satisfaction towards services and subjects.Different methods and techniques have been introduced to analyze sentiments for obtaining high accuracy.The sentiment analysis accuracy depends mainly on supervised and unsupervised mechanisms.Supervised mechanisms are based on machine learning algorithms that achieve moderate or high accuracy but the manual annotation of data is considered a time-consuming process.In unsupervised mechanisms,a lexicon is constructed for storing polarity terms.The accuracy of analyzing data is considered moderate or low if the lexicon contains small terms.In addition,most research methodologies analyze datasets using only 3-weight polarity that can mainly affect the performance of the analysis process.Applying both methods for obtaining high accuracy and efficiency with low user intervention during the analysis process is considered a challenging process.This paper provides a comprehensive evaluation of polarity weights and mechanisms for recent sentiment analysis research.A semi-supervised framework is applied for processing data using both lexicon and machine learning algorithms.An interactive sentiment analysis algorithm is proposed for distributing multi-weight polarities on Arabic lexicons that contain high morphological and linguistic terms.An enhanced scaling algorithm is embedded in the multi-weight algorithm to assign recommended weight polarities automatically.The experimental results are conducted on two datasets to measure the over-all accuracy of proposed algorithms that achieved high results when compared to machine learning algorithms. 展开更多
关键词 Sentiment analysis semi-supervised framework multi-weight polarity algorithm Arabic lexicons and automated scaling algorithm
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Low Power Polarity Conversion Based on the Whole Annealing Genetic Algorithm 被引量:4
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作者 汪鹏君 陆金刚 +1 位作者 陈恳 徐建 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第2期298-303,共6页
For an n-variable logic function,the power dissipation and area of the REED-MULLER (RM) circuit corresponding to each polarity are different. Based on the propagation algorithm of signal probability,the decompositio... For an n-variable logic function,the power dissipation and area of the REED-MULLER (RM) circuit corresponding to each polarity are different. Based on the propagation algorithm of signal probability,the decomposition algorithm of a multi-input XOR/AND gate,and the multiple segment algorithm of polarity conversion,this paper successfully applies the whole annealing genetic algorithm (WAGA) to find the best polarity of an RM circuit. Through testing eight large-scale circuits from the Microelectronics Center North Carolina (MCNC) Benchmark, the SYNOPSYS synthesis results show that the RM circuits corresponding to the best polarity found using the proposed algorithm attain average power,area,and max delay savings of 77.2% ,62.4% ,and 9.2% respectively,compared with those under polarity 0. 展开更多
关键词 whole annealing genetic algorithm REED-MULLER low power polarity conversion
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Determination of Structure and Polarity of Si C Single Crystal by X-Ray Diffraction Technique 被引量:1
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作者 郑新和 渠波 +2 位作者 王玉田 杨辉 梁骏吾 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第1期35-39,共5页
Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam pl... Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam ple has a6 H modification.The difference between the integrated intensities m easured byω scan in the triple- axis diffraction set- up finds some convincing evidence that the surface is either a Si- terminated face or C- terminated face.The experi- mental ratios of| F( 0 0 0 L) | 2 / | F( 0 0 0 L) | 2 are in good agreem entwith the calculated ones after the dispersion cor- rections to the atomic scattering factors( L=6 ,12 and18,respectively) .Thus,this m easurem ent technique is con- venient for the application of the materials with remarkable surface polarity. 展开更多
关键词 Si C single crystal polarity hexagonal6 H scattering factor
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Numerical Algorithm for Polarity Reversal Electric Field and Its Application 被引量:1
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作者 吕晓德 高本庆 《Journal of Beijing Institute of Technology》 EI CAS 1999年第2期50-55,共6页
Aim To analyze the transient speciality of nonlinear, anisotropic, AC+DC coupling electric field, and to compare the withstand voltage strength of different insulation structures. Methods The transient process o... Aim To analyze the transient speciality of nonlinear, anisotropic, AC+DC coupling electric field, and to compare the withstand voltage strength of different insulation structures. Methods The transient process of polarity reversal is analyzed, considering the anisotropic property of oil immersed press board, a new finite element model based on Galerkin method is presented and verified. The model developed is applied to calculate the electric field distribution in four typical winding end structures of the converter transformer. Results\ The whole ring structure possesses the best insulation characteristics. Conclusion\ By introducing reasonable insulation components, insulation strength with the same surrounding sizes can be improved more than 30%. 展开更多
关键词 ANISOTROPY finite element method polarity reversal INSULATION
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Effect of post weld heat treatment on properties of variable polarity TIG welded AA2219 aluminium alloy joints 被引量:13
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作者 丁吉坤 王东坡 +1 位作者 王颖 杜辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1307-1316,共10页
AA2219 aluminium alloy joints were fabricated by variable polarity tungsten inert gas (VPTIG) welding process and the effects of post weld heat treatment (PWHT) on the tensile properties, microstructure and fatigu... AA2219 aluminium alloy joints were fabricated by variable polarity tungsten inert gas (VPTIG) welding process and the effects of post weld heat treatment (PWHT) on the tensile properties, microstructure and fatigue behaviour of the welded joints were investigated. The VPTIG welding process was adopted because it could meet the need of cathode cleaning and meanwhile it could reduce the deterioration of tungsten electrode furthest. The welded samples were divided into as-welded (AW) sample and PWHT sample. The PWHT method used on the samples was solution treatment (535 ℃, 30 rain), water quenching and artificial aging (175 ℃, 12 h). The experimental results show that, compared with the AW samples, the microstructure characteristics and mechanical properties of the AA2219 joints after PWHT were significantly improved. The improvement of yield strength, ultimate tensile strength, and fatigue strength are 42.6%, 43.1% and 18.4%, respectively. 展开更多
关键词 AA2219 aluminium alloy variable polarity TIG post weld heat treatment mechanical properties MICROSTRUCTURE fatigue behaviour
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The Arabidopsis AS2 Gene Encoding a Predicted Leucine-zipper Protein Is Required for the Leaf Polarity Formation
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作者 徐轶 孙越 +1 位作者 梁婉琪 黄海 《Acta Botanica Sinica》 CSCD 2002年第10期1194-1202,共9页
The asymmetric leaves2 ( as2) is a classical Arabidopsis thaliana (L.) Heynh. mutant that shows leaf lobes and leaflet-like structures from the petioles of leaves. Genetic and molecular analyses have demonstrated that... The asymmetric leaves2 ( as2) is a classical Arabidopsis thaliana (L.) Heynh. mutant that shows leaf lobes and leaflet-like structures from the petioles of leaves. Genetic and molecular analyses have demonstrated that the AS2 function is required for repression of meristem-related homeobox genes in leaves. In this study, we describe phenotypic characterizations of new as2 alleles that are in the Landsberg erecta (Ler) genetic background. In addition to the as2 phenotypes reported previously, the new as2 mutants have some leaves with petiole growth underneath the leaf blade, showing a lotus-leaf structure. More severe rosettes leaves of the as2 mutants form a filament-like structure, reflecting a loss of the adaxial-abaxial polarity in leaves. Among as2 mutants analyzed in different genetic backgrounds, only those that are in the Ler genetic background resulted in a high frequency of the lotus-leaf structure. We have isolated the AS2 gene by map-based gene cloning. The predicted AS2 protein contains a leucine-zipper motif, and its N-terminus shares high levels of sequence similarity to those of a group of predicted proteins with no known biological functions. AS2 transcripts were detected in leaves, flowers and fruits, but absent in stems, consistent with the mutant phenotypes. 展开更多
关键词 Arabidopsis thaliana ASYMMETRIC LEAVES1 ASYMMETRIC LEAVES2 ERECTA leucine-zipper motif polarity formation
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Transcriptional,post-transcriptional and post-translational regulations of gene expression during leaf polarity formation 被引量:9
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作者 Lin Xu Li Yang Hai Huang 《Cell Research》 SCIE CAS CSCD 2007年第6期512-519,共8页
Leaf morphogenesis requires the establishment of adaxlal-abaxlal polarity after primordium initiation from the snoot apical meristem (SAM). Several families of transcription factors are known to play critical roles ... Leaf morphogenesis requires the establishment of adaxlal-abaxlal polarity after primordium initiation from the snoot apical meristem (SAM). Several families of transcription factors are known to play critical roles in promoting adaxial or abaxial leaf fate. Recently, post-transcriptional gene silencing pathways have been shown to regulate the establishment of leaf polarity, providing novel and exciting insights into leaf development. For example, microRNAs (miR 165/166) and a trans-acting siRNA (TAS3-derived tasiR-ARF) have been shown to repress the expression of several key transcription factor genes. In addition, yet another level of regulation, post-translational regulation, has been revealed recently by studies on the role of the 26S proteasome in leaf polarity. Although our understanding regarding the molecular mecha- nisms underlying establishment of adaxial-abaxial polarity has greatly improved, there is still much that remains elusive. This review aims to discuss recent progress, as well as the remaining questions, regarding the molecular mechanisms underlying leaf polarity formation. 展开更多
关键词 ARABIDOPSIS leaf development polarity formation
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Arc magmatism as a window to plate kinematics and subduction polarity:Example from the eastern Pontides belt,NE Turkey 被引量:6
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作者 Yener Eyuboglu M.Santosh +1 位作者 Osman Bektas Seda Ayhan 《Geoscience Frontiers》 SCIE CAS 2011年第1期49-56,共8页
The Eastern Pontides orogenic belt in the Black Sea region of Turkey offers a critical window to plate kinematics and subduction polarity during the closure of the Paleotethys. Here we provide a brief synthesis on rec... The Eastern Pontides orogenic belt in the Black Sea region of Turkey offers a critical window to plate kinematics and subduction polarity during the closure of the Paleotethys. Here we provide a brief synthesis on recent information from this belt. We infer a southward subduction for the origin of the Eastern Pontides orogenic belt and its associated late Mesozoic--Cenozoic magmatism based on clear spatial and temporal variations in Late Cretaceous and Cenozoic arc magmatism, together with the exis- tence of a prominent south-dipping reverse fault system along the entire southern coast of the Black Sea. Our model is at variance with some recent proposals favoring a northward subduction polarity, and illus- trates the importance of arc magmatism in evaluating the geodynamic milieu associated with convergent margin orocesses. 展开更多
关键词 TURKEY Eastern Pontides belt Subduction polarity Arc magmatism PALEOMAGNETISM
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EFFECTS OF SOLVENT POLARITY ON INFINITE DIFFUSION COEFFICIENTS IN SUPERCRITICAL ETHANOL 被引量:5
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作者 楚彩云 张宝泉 +1 位作者 刘秀凤 林跃生 《化工学报》 EI CAS CSCD 北大核心 2004年第6期1021-1023,共3页
关键词 TAYLOR DISPERSION technique diffusion COEFFICIENT SUPERCRITICAL ETHANOL polarity
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Characteristics of arc in variable polarity plasma arc welding of aluminum alloy 被引量:6
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作者 洪海涛 韩永全 +1 位作者 杜茂华 吴永军 《China Welding》 EI CAS 2014年第3期73-77,共5页
A double invert variable polarity plasma arc (VPPA) power source based on 16-bit MCU applied for aluminum alloys was developed. Mechanics, electrical and the produced heat mechanism of VPPAW arc were tested and anal... A double invert variable polarity plasma arc (VPPA) power source based on 16-bit MCU applied for aluminum alloys was developed. Mechanics, electrical and the produced heat mechanism of VPPAW arc were tested and analyzed. Results indicate that during the VPPA welding procedure of aluminum alloy, the arc of electrode negative (EN) has more effect on force, whereas the arc of electrode positive ( EP ) has more effect on heat. It should be noted that keeping the balance of the force and heat is the critical element of VPPAW. This power source had been successfully used to weld aluminum alloy with a 15 mm thickness in vertical welding. The conclusions are applicable to the variable polarity plasma arc welding technique used in the aerospace industry. 展开更多
关键词 variable polarity plasma arc arc pressure aluminum alloy
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Dynamic response of concrete face rockfill dam affected by polarity reversal of near-fault earthquake 被引量:3
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作者 Jiang Qiuting Zou Degao +1 位作者 Han Huichao Liu Jingmao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第1期81-99,共19页
In China,an increasing number of high concrete face rockfill dams(CFRDs)are located in high intensity earthquake zones,some of which are close to the seismic fault line.Recordings suggest that near-fault ground motion... In China,an increasing number of high concrete face rockfill dams(CFRDs)are located in high intensity earthquake zones,some of which are close to the seismic fault line.Recordings suggest that near-fault ground motions are characterized by large one-sided velocity pulses.The conventional dynamic analysis of dams,however,neglects the features of strong ground movements.In this study,under different ground motion levels some numerical dynamic studies considering the one-sided broadband pulses of near-fault earthquakes are presented for CFRDs based on a generalized plasticity model for rockfill materials.The results indicate that the displacements of dam crest corresponding to positive and reverse input of near-fault ground motion make a significant difference,while the displacements of the dam crest under artificial seismic waves are similar.Furthermore,using the horizontal and vertical components as simultaneous excitations near the faults,the displacements of the dam crest before and after reversing the motion produce a larger difference than that using a single component.More importantly,the difference of horizontal displacements of the dam crest caused by polarity reversal of near-fault ground motions increases with the increase of earthquake intensity.Due to the randomness and uncertainties of earthquakes,using a stochastic near-field motion input as excitation without considering the polarity(i.e.,positive vs reversed waveform),does not necessarily obtain a conservative result. 展开更多
关键词 near-fault ground motion polarity high concrete face rockfill dam dynamic response
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Development of Rice Leaves:How Histocytes Modulate Leaf Polarity Establishment 被引量:2
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作者 Wang Jiajia Xu Jing +1 位作者 Qian Qian Zhang Guangheng 《Rice science》 SCIE CSCD 2020年第6期468-479,共12页
An ideal leaf shape is beneficial to the yield of rice.Molecular understanding of the leaf primordia and polarity establishment plays a significant role in exploring the genetic regulatory network of leaf morphogenesi... An ideal leaf shape is beneficial to the yield of rice.Molecular understanding of the leaf primordia and polarity establishment plays a significant role in exploring the genetic regulatory network of leaf morphogenesis.In recent years,researchers have cloned an array of coding genes and a few non-coding small RNAs involved in rice leaf development through regulating the development of leaf primordia,vascular bundles,sclerenchyma cells,bulliform cells,cell walls and epidermis cells.These genes and their interactions play critical roles in rice leaf development through the determination and regulatory role in gene expression,and their coordination with other genetic networks or signal pathways.But the relationship among these genes is poorly defined and the underlying network is still unclear.In this review,we introduced the regulatory pathways of leaf primordium development and leaf polarity establishment,mainly the relationship between cell development mechanism and leaf polarity establishment,focusing on how leaf tissue affects leaf shape.Hopefully,the regulation network reviewed here has immediate implications for future research and genomic design breeding. 展开更多
关键词 RICE leaf morphogenesis molecular mechanism tissue cell leaf polarity establishment
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A novel variable polarity welding power based on high-frequency pulse modulation 被引量:3
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作者 邱灵 杨春利 +2 位作者 范成磊 林三宝 伍昀 《China Welding》 EI CAS 2006年第3期11-15,共5页
A new type of variable polarity welding power modulated with high-frequency pulse current is developed. Series of high-frequency pulse current is superimposed on direct-current-electrode-negative (DCEN), which can i... A new type of variable polarity welding power modulated with high-frequency pulse current is developed. Series of high-frequency pulse current is superimposed on direct-current-electrode-negative (DCEN), which can improve the crystallization process in the weld bead as a result of the electromagnetic force generated by pulse current. Digital signal processor (DSP) is used to realize the closed-loop control of the first inverter, variable polarity output of the second inverter and high-frequency pulse current superposition. 展开更多
关键词 variable polarity welding digital signal processor DSP) high-frequency pulse current pulse current welding
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Cell polarity protein Par3 complexes with DNA-PK via Ku70 and regulates DNA double-strand break repair 被引量:2
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作者 Longhou Fang YiGuo Wang +6 位作者 Dan Du Guang Yang Tim Tak Kwok Siu Kai Kong Benjamin Chen David J Chen Zhengjun Chen 《Cell Research》 SCIE CAS CSCD 2007年第2期100-116,共17页
The partitioning-defective 3 (Par3), a key component in the conserved Par3/Par6/aPKC complex, plays fundamental roles in cell polarity. Herein we report the identification of Ku70 and Ku80 as novel Par3-interacting ... The partitioning-defective 3 (Par3), a key component in the conserved Par3/Par6/aPKC complex, plays fundamental roles in cell polarity. Herein we report the identification of Ku70 and Ku80 as novel Par3-interacting proteins through an in vitro binding assay followed by liquid chromatography-tandem mass spectrometry. Ku70/Ku80 proteins are two key regulatory subunits of the DNA-dependent protein kinase (DNA-PK), which plays an essential role in repairing double-strand DNA breaks (DSBs). We determined that the nuclear association of Par3 with Ku70/Ku80 was enhanced by γ-irradiation (IR), a potent DSB inducer. Furthermore, DNA-PKcs, the catalytic subunit of DNA-PK, interacted with the Par3/Ku70/Ku80 complex in response to IR. Par3 over-expression or knockdown was capable of up- or downregulating DNA-PK activity, respectively. Moreover, the Par3 knockdown cells were found to be defective in random plasmid integration, defective in DSB repair following IR, and radiosensitive, phenotypes similar to that of Ku70 knockdown cells. These findings identify Par3 as a novel component of the DNA-PK complex and implicate an unexpected link of cell polarity to DSB repair. 展开更多
关键词 cell polarity DSB repair DNA-PK Ku70/Ku80/Par3
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Welding Polarity Effects on Weld Spatters and Bead Geometry of Hyperbaric Dry GMAW 被引量:9
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作者 XUE Long WU Jinming +3 位作者 HUANG Junfen HUANG Jiqiang ZOU Yong LIU Jian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第2期351-356,共6页
Welding polarity has influence on welding stability to some extent, but the specific relationship between welding polarity and weld quality has not been found, especially under the hyperbaric environment. Based on a h... Welding polarity has influence on welding stability to some extent, but the specific relationship between welding polarity and weld quality has not been found, especially under the hyperbaric environment. Based on a hyperbaric dry welding experiment system, gas metal arc welding(GMAW) experiments with direct current electrode positive(DCEP) and direct current electrode negative(DCEN) operations are carried out under the ambient pressures of 0.1 MPa, 0.4 MPa, 0.7 MPa and 1.0 MPa to find the influence rule of different welding polarities on welding spatters and weld bead geometry. The effects of welding polarities on the weld bead geometry such as the reinforcement, the weld width and the penetration are discussed. The experimental results show that the welding spatters gradually grow in quantity and size for GMAW with DCEP, while GMAW with DCEN can produce fewer spatters comparatively with the increase of the ambient pressure. Compared with DCEP, the welding current and arc voltage waveforms for DCEN is more stable and the distribution of welding current probability density for DCEN is more concentrated under the hyperbaric environment. When the ambient pressure is increased from 0.1 MPa to 1.0 MPa, the effects of welding polarities on the reinforcement, the weld width and the penetration are as follows: an increase of 0.8 mm for the weld reinforcement is produced by GMAW with DCEN and 1.3 mm by GMAW with DCEP, a decrease of 7.2 mm for the weld width is produced by DCEN and 6.1 mm by DCEP; and an increase of 3.9 mm for the penetration is produced by DCEN and 1.9 mm by DCEP. The proposed research indicates that the desirable stability in the welding procedure can be achieved by GMAW with DCEN operation under the hyperbaric environment. 展开更多
关键词 welding polarity hyperbaric welding gas metal arc welding(GMAW) weld bead geometry spatter
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