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| 1 | Mathematic principles of interrupted-sampling repeater jamming (ISRJ)显示文摘Coherent jamming is one of the important trends in modern radar electronic war- fare. High-speed sampling of wideband radio frequency (RF) signals and high iso- lation of two receive-transmit antennas are key technologies for the realization of coherent jamming. However, these technologies present significant challenges to engineering application. In this paper, a novel repeater jamming based on inter- rupted sampling technique is presented. For a jammer with a receive-transmit time-sharing antenna, a radar signal is sampled with a low rate by the jammer. Then, a train of false targets will be achieved after the jamming signal feed the matched filter of a pulse compression radar. For the case of the linear frequency modulated (LFM) pulse compression radars, mathematic principles of the interrupted-sam- pling repeater jamming is developed, and then the efficiency of the jamming is de- scribed and stated as expressions of key parameters which are also beneficial to the jamming design for other coherent radars. | WANG XueSong LIU JianCheng ZHANG WenMing FU QiXiang LIU Zhong XIE XiaoXia | 2007 | Science in China(Series F)2007，50，1： | 53 |
| 2 | New paleontological evidence on time determination of the east part of the Eastern Kunlun Mélange and its tectonic significance显示文摘New paleontological evidence suggests that the composition of the matrix and slices from the middle and the south of the Eastern Kunlun Mélange Belt is very complex, ranging from Proterozoic to Mesozoic in geological time. A Cambrian acritarch assemblage has been discovered from the middle part of the Eastern Kunlun Mélange, a Neoproterozoic to the early Paleozoic acritarch assemblage has been discovered from the south of the Eastern Kunlun Mé lange, and so has been an Early Permian radiolarian from the A’nyemaqen Mélange in Buqing- shan. In addition, some sporopollen has been obtained from the Mesozoic tectonic slices. The above-mentioned paleontological evidence indicates that the Eastern Kunlun Orogenic Belt experienced two episodes from ocean to continent from the Neoproterozoic to the Early Paleo- zoic and in the Late Paleozoic respectively. In the process of intracontinent development in Mesozoic, because of heavy thrust-nappe, strike-slip sheer and crust shortening, the Mesozoic formation was intercalated in mélange by slices and the Eastern Kunlun Orogenic Belt became more complex. | ZHANG Kexin LIN Qixiang ZHU Yunhai YIN Hongfu LUO Mansheng CHEN Nengsong WANG Guocan | 2004 | Science China Earth Sciences2004，47，10： | 17 |
| 3 | A new procedure to estimate the rainfall erosivity factor based on Tropical Rainfall Measuring Mission(TRMM) data显示文摘Soil erosion by water is the most important land degradation problem worldwide.In this paper a new procedure was developed to estimate the rainfall-runoff erosivity factor(R)based on Tropical Rainfall Measuring Mission(TRMM)satellite-estimated precipitation data,which consists of 3-h rainfall intensity data.In this method,R was calculated as the product of the maximum 180-min rainfall intensity and the rainfall energy.This procedure was applied to the Daling River basin in Liaoning Province,China,R in terms of yearly,monthly and event-based rainfall in 2005 was computed separately using TRMM 3B42 data.The TRMM data showed a significant correlation with the interpolated rain-gauge data.Furthermore,because the TRMM data are based on rainfall intensity,they can represent the impact on erosion more accurately.It reflects both the spatial distribution and the intensity of rainfall.The procedure is a new approach to estimate the rainfall erosivity for soil water erosion modeling,especially in areas lacking rain-gauge stations. | ZHU Qiang CHEN XiuWan FAN QiXiang JIN HePing LI JiRen | 2011 | Science China(Technological Sciences)2011，54，9： | 15 |
| 4 | Magnetoresistance enhancement and temperature stability of magnetoresistance in La_(1-x)(Sr_(1-y)Na_y)_xMnO_3显示文摘A series of the samples La_(1-x)(Sr_(1-y)Na_y)_xMnO_3(y=0.0,0.2,0.4,0.6,0.8,1.0) were prepared by the solid-state reaction method.Magnetoresistance enhancement and temperature stability of magnetoresistance in the system La_(1-x)(Sr_(1-y)Na_y)_xMnO_3 with unchanged Mn^(3+)/Mn^(4+) ratio through the doping of both monovalent and divalent elements at A site were studied through the measurements of X-ray diffraction(XRD) patterns,resistivity-temperature(ρ-T) curves and magnetoresistance-temperature(MR-T) curves.The results indicate that with the increase of Na doping amount,the peak value of MR increases,and it increases from 12.4% for y=0.2 to 50.6% for y=1.0 in the magnetic field B=0.8 T;ρ-T curves exhibit the double-peak phenomenon,which comes from the competition between the resistivity of surface phase and that of body phase;for the sample of y=0.8,MR increases slowly from 8.3% to 9.4% in the temperature range from 259 to 179 K,and MR is so stable in such a wide temperature range,which provides reference for the research on the temperature stability of MR. | Wang, Guiying Yan, Guoqing Yang, Jie Wang, Wenqi Tang, Yonggang Song, Qixiang Zhang, Mingyu Peng, Zhensheng | 2012 | Rare Metals2012，31，4： | 13 |
| 5 | Exhaustion and senescence: two crucial dysfunctional states of T cells in the tumor microenvironment显示文摘The failure of a massive influx of tumor-infiltrating T lymphocytes to eradicate tumor cells in the tumor microenvironment is mainly due to the dysfunction of T cells hyporesponsive to tumors.T-cell exhaustion and senescence induced by malignant tumors are two important dysfunctional states that coexist in cancer patients,hindering effective antitumor immunity and immunotherapy and sustaining the suppressive tumor microenvironment.Although exhausted and senescent T cells share a similar dysfunctional role in antitumor immunity,they are distinctly different in terms of generation,development,and metabolic and molecular regulation during tumor progression.Here,we discuss the unique phenotypic and functional characteristics of these two types of dysfunctional T cells and their roles in tumor development and progression.In addition,we further discuss the potential molecular and metabolic signaling pathways responsible for the control of T-cell exhaustion and senescence in the suppressive tumor microenvironment.Understanding these critical and fundamental features should facilitate rethinking the unresponsiveness to current immunotherapies in clinical patients and lead to further development of novel and effective strategies that target different types of dysfunctional T cells to enhance cancer immunotherapy. | Yangjing Zhao Qixiang Shao Guangyong Peng | 2020 | Cellular & Molecular Immunology2020，17，1： | 11 |
| 6 | Enhancement of room-temperature magnetoresistance in La_(0.6)Dy_(0.1)Sr_(0.3)MnO_3/Ag_x显示文摘The samples of La0.6Dy0.1Sr0.3MnO3/(Ag2O)x/2(x = 0.00, 0.02, 0.04, 0.06, 0.08, 0.10, 0.20, 0.25, and 0.30) were prepared by using the solid-state reaction method.Their magnetic property, transport behavior, transport mechanism and magnetoresistance effect were studied through the measurements of magnetization-temperature(M-T) curves, ρ-T curves and the fitting of ρ-T curves.The results indicated that Ag could take part in the reaction when the doping amount is small.However, when the doping amount is comparatively large, Ag as metallic state mainly deposits on the grain boundary of La0.6Dy0.1Sr0.3MnO3, and then the system forms a two-phase composite.When the Ag doping amount is 30% mole ratio, the resistivity of the sample is one order of magnitude smaller than that of low doped samples, and its peak of magnetoresistance at 292 K and in the magnetic field of 0.2 T strengthens apparently and reaches 16.3%, which is over 7 times as large as 2.2% of La0.6Dy0.1Sr0.3MnO3.The two-phase composite system of magnetoresistance based on perovskite manganite consists of two parts:intrinsic magnetoresistance and extrinsic magnetoresistance.However, extrinsic magnetoresistance comes from spin-dependent scattering(SDS) and spin-polarized tunneling(SPT).Magnetoresistance near TC increases due to the contribution of intrinsic magnetoresistance and extrinsic magnetoresistance formed by SDS, and magnetoresistance at low temperature is extrinsic magnetoresistance formed by SPT. | SONG Qixiang NIU Xiaofei WANG Guiying TANG Yonggang CAI Zhirang PENG Zhensheng | 2010 | Rare Metals2010，29，2： | 10 |
| 7 | Acute and chronic toxic effects of Pb^(2+)on polychaete Perinereis aibuhitensis:Morphological changes and responses of the antioxidant system显示文摘Perinereis aibuhitensis was used to assess adverse biological effects caused by acute and chronic Pb2+exposure in artificial seawater under controlled laboratory conditions. In 96-hr acute toxicity experiments,the morphological changes showed a positive time/dose-dependent tendency,and the 96-hr LC50 value of Pb2+was 686.41 mg/L. The responses of enzymatic and non-enzymatic antioxidants in tissues including catalase(CAT),peroxidase(POD),superoxide dismutase(SOD),glutathione peroxidase(GSH-PX),malondialdehyde(MDA) and the content of total soluble protein(TSP),were investigated on days 1,4,7 and 10 after Pb2+exposure under chronic toxicity testing. Results showed that the activation of the antioxidant system in P. aibuhitensis depended on the Pb2+concentration and the duration of exposure time.Specifically,POD and SOD activities were induced on the first day of the exposure and decreased to the control level on day 10 after exposure. Therefore,these two indexes could be used to indicate oxidative stress associated with P. aibuhitensis exposure to Pb2+. | Yulu Tian Hongjun Liu Qixiang Wang Jian Zhou Xuexi Tang | 2014 | Journal of Environmental Sciences2014，26，8： | 8 |
| 8 | Low-field magnetoresistance of (1-x)La_(0.6)Dy_(0.1)Sr_(0.3)MnO_3/0.5x (Sb_2O_3) composite system under different sintering temperatures of matrix显示文摘A series of (1-x)La0.6Dy0.1Sr0.3MnO3/0.5x(Sb2O3)(x=0.15) samples were prepared by the solid-state reaction method, and the influence of sintering temperature of the matrix on low-field magnetoresistance of (1-x)La0.6Dy0.1Sr0.3MnO3/0.5x (Sb2O3) was studied through the measurements of X-ray diffraction (XRD) patterns, scanning electron microscope (SEM) image, resistivity-temperature (ρ-T) curves, and magnetoresistance-temperature (MR-T) curves. The results indicate that for the samples with low sintering temperature of the matrix, lowfield magnetoresistance effect appears on the whole temperature range and can be explained by grain boundary effect; for the sample with high sintering temperature of the matrix, intrinsic magnetoresistance peak appears on the high-temperature range, low-field magnetore-sistance effect appears on low temperature range, and the magnetoresistance in the magnetic field of 0.2 T and on the comparatively large temperature range between 280 K and 225 K hardly changes with temperature and remains at 4.8%, which can be explained by the competition between the intrinsic magnetoresistance induced by double-exchange function inside grains and the tunneling magnetoresis-tance (TMR) induced by grain boundary effect. The temperature stability of magnetoresistance is beneficial to the practical applications of MR. | Yang, Jie Yan, Guoqing Wang, Guiying Tang, Yonggang Song, Qixiang Zhang, Mingyu Peng, Zhensheng | 2012 | Rare Metals2012，31，3： | 7 |
| 9 | On Hrmander condition显示文摘LET T:D→D′be a continuous linear operatorl, and K denote the distribution kernel of T. Assume that restriction of K to the set{( x, y ) ∈R^n x R^n, x≠y}satisfies the following 'size' and 'smoothness' conditions: | YANG Qixiang, YAN Lixin and DENG DonggaoDepartment of Mathematics, Zhongshan University, Guangzhou 510275, China | 1997 | Chinese Science Bulletin1997，42，16： | 7 |
| 10 | Precipitation behaviors of X70 acicular ferrite pipeline steel显示文摘The morphology, structure, and chemical composition of precipitates in the final microstructure of Nb-V-Ti microalloyed X70 acicular ferrite pipeline steel were investigated using transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). Precipitates observed by TEM can be classified into two groups. The large precipitates are complex compounds that comprise square-shaped TiN precipitate as core with fine Nb-containing precipitate nucleated on pre-existing TiN precipitate as caps on one or more faces at high temperature. In contrast, the fine and spherical Nb carbides and/or carbonitrides precipitate heterogene-ously on dislocations and sub-boundaries at low temperature. From the analysis in terms of thermodynamics, EDS and chemical composition of the steel, NbC precipitation is considered to be the predominant precipitation behavior in the tested steel under the processing conditions of this research. | Hao Yu Yi Sun Qixiang Chen Haitao Jiang Lihong Zhang | 2006 | Journal of University of Science and Technology Beijing2006，13，6： | 6 |
| 11 | Photoperiod-and temperature-mediated control of the ethylene response and winter dormancy induction in Prunus mume显示文摘Plant dormancy is essential for perennial plant survival.Different genotypes of Prunus mume,including Eumume group and Apricot Mei group,undergo leaf senescence and dormancy at different times.In order to verify the cold resistance of P.mume,freeze resistance evaluation was carried out.Our results showed that Apricot Mei group had a stronger freezing tolerance than Eumume group and that leaf senescence and dormancy of Apricot Mei group occurred at an earlier period before winter.Based on phenotypic data in response to seasonal climate change,the significant candidate regions were selected using GWAS.Furthermore,through KEGG pathway and qRT-PCR analyses,we found that the ethylene-related genes,including PmEIL(Pm002057)and PmERF(Pm004265),were significantly upregulated in‘Songchun’Mei(Apricot Mei group)and downregulated in‘Zaohua Lve’Mei(Eumume group).Ethylene-related genes expression models showed that ethylene may be indirectly involved in the induction of dormancy.The PmEIL and PmERF genes were the core genes of the ethylene signal transduction pathway and were regulated by the exogenous ACC or PZA compounds.For non-dormant or weekly dormant perennial plants,application of ACC was able to induce plant dormancy and thus enhance cold/freeze tolerance.Overall,the expression of the major ethylene genes played a significant role in dormancy induction and freezing tolerance in P.mume;accordingly,application of ACC and PZA compounds were an effective approach for enhancing cold/freeze of tolerance of woody plant. | Ping Li Tangchun Zheng Xiaokang Zhuo Man Zhang Xue Yong Lulu Li Jia Wang Tangren Cheng Qixiang Zhang | 2021 | Horticultural Plant Journal2021，7，3： | 6 |
| 12 | Optimization design of foundation excavation for Xiluodu super-high arch dam in China显示文摘With better understanding of the quality and physico-mechanical properties of rocks of dam foundation,and the physico-mechanical properties and structure design of arch dam in association with the foundation excavation of Xiluodu arch dam,the excavation optimization design was proposed for the foundation surface on the basis of feasibility study.Common analysis and numerical analysis results demonstrated the feasibility of using the weakly weathered rocks III1and III2as the foundation surface of super-high arch dam.In view of changes in the geological conditions at the dam foundation along the riverbed direction,the design of extending foundation surface excavation area and using consolidating grouting and optimizing structure of dam bottom was introduced,allowing for harmonization of the arch dam and foundation.Three-dimensional(3D)geomechanics model test and fi nite element analysis results indicated that the dam body and foundation have good overload stability and high bearing capacity.The monitoring data showed that the behaviors of dam and foundation correspond with the designed patterns in the construction period and the initial operation period. | Qixiang Fan Shaowu Zhou Ning Yang | 2015 | Journal of Rock Mechanics and Geotechnical Engineering2015，7，2： | 6 |
| 13 | Transcriptome profiles reveal that gibberellin-related genes regulate weeping traits in crape myrtle显示文摘Plant architecture includes vital traits that influence and benefit crops,and economically important trees.Different plant architectures provide natural beauty.Weeping ornamental plants are aesthetically appealing to people.The regulatory mechanism controlling the weeping trait is poorly understood in crape myrtle.To investigate the weeping trait mechanism,transcriptional profiling of different organs in weeping and upright crape myrtle was performed based on phenotype.Phenotypic and histological analyses demonstrated that endodermal cells were absent,and that new shoot phenotypes could be rescued by the GA3 treatment of weeping plants.The transcriptional analysis and coexpression network analysis(WGCNA)of differentially expressed genes indicated that GA synthesis and signal transduction pathways play a role in weeping traits.When the expression level of a negative element of GA signaling,LfiGRAS1,was reduced by virus-induced gene silencing(VIGS),new branches grew in infected plants in a negatively geotropic manner.An integrated analysis implied that GA had a strong influence on weeping crape myrtle by interacting with other factors.This study helps to elucidate the mechanism governing the weeping trait and can improve the efficiency of breeding in Lagerstroemia. | Suzhen Li Tangchun Zheng Xiaokang Zhuo Zhuojiao Li Lulu Li Ping Li Like Qiu Huitang Pan Jia Wang Tangren Cheng Qixiang Zhang | 2020 | Horticulture Research2020，7，1： | 5 |
| 14 | Commuting Solutions of a Quadratic Matrix Equation for Nilpotent Matrices显示文摘我们与给定的 nilpotent 矩阵 A 解决二次的矩阵方程 AXA = XAX,到发现所有变换答案。我们首先提供一个关键词根,并且认为 A 有的特殊情况是一仅仅乔丹块为一般的格激发这个想法。我们的主要结果与一个任意的 nilpotent 矩阵给方程的所有变换答案的结构。 | Qixiang Dong Jiu Ding Qianglian Huang | 2018 | Algebra Colloquium2018，25，1： | 4 |
| 15 | Targeted deletion of floral development genes in Arabidopsis with CRISPR/Cas9 using the RNA endoribonuclease Csy4 processing system显示文摘The formation of flowers in higher plants is controlled by complex gene regulatory networks.The study of floral development in Arabidopsis is promoted and maintained by transposon-tagged mutant lines.In this study,we report a CRISPR/Cas9 genome-editing system based on RNA endoribonuclease Csy4 processing to induce high-efficiency and inheritable targeted deletion of transcription factors involved in floral development in Arabidopsis.Using AP1,SVP,and TFL1 as the target genes,multisite and multiple-gene mutations were achieved with a tandemly arrayed Csy4-sgRNA architecture to express multiplexed sgRNAs from a single transcript driven by the Pol II promoter in transgenic lines.Targeted deletions of chromosomal fragments between the first exon and second exon in either one or three genes were generated by using a single binary vector.Interestingly,the efficiency of site-targeted deletion was comparable to that of indel mutation with the multiplexed sgRNAs.DNA sequencing analysis of RT-PCR products showed that targeted deletions of AP1 and TFL1 could lead to frameshift mutations and introduce premature stop codons to disrupt the open-reading frames of the target genes.In addition,no RT-PCR amplified product was acquired after SVPtargeted deletion.Furthermore,the targeted deletions resulted in abnormal floral development in the mutant lines compared to that of wild-type plants.AP1 and SVP mutations increased plant branching significantly,while TFL1 mutant plants displayed a change from indeterminate to determinate inflorescences.Thus,our results demonstrate that CRISPR/Cas9 with the RNA endoribonuclease Csy4 processing system is an efficient tool to study floral development and improve floral traits rapidly and simply. | Yingzhu Liu Yike Gao Yaohui Gao Qixiang Zhang | 2019 | Horticulture Research2019，6，1： | 4 |
| 16 | EFFECT OF THE RIBLETS SURFACE ON THE BOUNDARY LAYER DEVELOPMENT显示文摘EFFECT OF THE RIBLETS SURFACE ON THE BOUNDARY LAYER DEVELOPMENTWangJinjun;LanShilong;LianQixiang(InstituteofFluidMechanicsIBe... | Wang Jinjun Lan Shilong Lian Qixiang(Institute of Fluid Mechanics I Beijing University of Aeronautics | 1996 | Chinese Journal of Aeronautics1996，9，4： | 4 |
| 17 | Monitoring result analyses of high slope of five-step ship lock in the Three Gorges Project显示文摘The construction of the double-lane fi ve-step ship lock of the Three Gorges Project(TGP)was commenced in 1994,the excavation of the ship lock was completed by the end of 1999,and the ship lock was put in operation in June 2003.The side slopes of the ship lock are characterized by great height(170 m),steepness(70 m in height of upright slope),and great length(over 7000 m in total length).In association with the ship lock,the surrounding rocks in slope have a high potential to deform,with which the magnitude of deformation is restricted.Monitoring results show that the deformation of the fi ve-step ship lock high slopes of the TGP primarily occurred in excavation period,and deformation tended to be stable and convergent during operation period,suggesting the allowable ranges of deformation.At present,the slopes and lock chambers are stable,and the ship lock works well under normal operation condition,enabling the social and economic bene fi ts of the TGP. | Qixiang Fan Hongbing Zhu Jun Gen | 2015 | Journal of Rock Mechanics and Geotechnical Engineering2015，7，2： | 4 |
| 18 | Unloading performances and stabilizing practices for columnar jointed basalt:A case study of Baihetan hydropower station显示文摘The columnar jointed rock mass(CJR), composed of polygonal cross-sectional columns cut by several groups of joints in various directions, was exposed during the excavations of the Baihetan hydropower station, China. In order to investigate the unloading performances and the stability conditions during excavation of the columns, an experimental field study was performed. Firstly, on-site investigations indicated that the geotechnical problems, including rock relaxation, cracking and collapse, were the most prominent for the CJR Class I that contains intensive joint network and the smallest column sizes.Comprehensive field tests, including deformation measurement by multi-point extensometers, ultrasonic wave testing, borehole television observation and stress monitoring of rock anchors, revealed that the time-dependent relaxation of the CJRs was marked. The practical excavation experiences for the Baihetan columnar jointed rock masses, such as blasting scheme, supporting time of shotcrete and rock bolts, were presented in the excavations of the diversion tunnels. These detailed investigations and practical construction experiences can provide helpful information for similar geotechnical works in jointed rock mass. | Qixiang Fan Xiating Feng Wenlin Weng Yilin Fan Quan Jiang | 2017 | Journal of Rock Mechanics and Geotechnical Engineering2017，9，6： | 4 |
| 19 | Hot Corrosion Behavior of a Cr-Modified Aluminide Coating on a Ni-Based Superalloy显示文摘A Cr-modified aluminide coating is prepared on a Ni-based superalloy using arc ion plating and subsequent pack cementation aluminizing.Hot corrosion behavior of the Cr-modified aluminide coating exposed to molten Na2SO4/K2SO4(3:1) or Na2SO4/NaCl(3:1) salts at 900 °C in static air are evaluated as well as the aluminide coating.The results indicate that compared with the aluminide coating,the anti-corrosion properties of the Cr-modified aluminide coating in the both salts are improved,which should be attributed to the beneficial effect of the Cr in the coating.The corrosion mechanism of the Cr-modified aluminide coating,especially the role of Cr in the mixture salt corrosion,is discussed. | Duoli Wu Sumeng Jiang Qixiang Fan Jun Gong Chao Sun | 2014 | Acta Metallurgica Sinica(English Letters)2014，27，4： | 4 |
| 20 | Kinetics and mechanisms of mitotic inheritance of DNA methylation and their roles in aging-associated methylome deterioration显示文摘Mitotic inheritance of the DNA methylome is a challenging task for the maintenance of cell identity.Whether DNA methylation pattern in different genomic contexts can all be faithfully maintained is an open question.A replication-coupled DNA methylation maintenance model was proposed decades ago,but some observations suggest that a replication-uncoupled maintenance mechanism exists.However,the capacity and the underlying molecular events of replication-uncoupled maintenance are unclear.By measuring maintenance kinetics at the single-molecule level and assessing mutant cells with perturbation of various mechanisms,we found that the kinetics of replication-coupled maintenance are governed by the UHRF1–Ligase 1 and PCNA–DNMT1 interactions,whereas nucleosome occupancy and the interaction between UHRF1 and methylated H3K9 specifically regulate replication-uncoupled maintenance.Surprisingly,replication-uncoupled maintenance is sufficiently robust to largely restore the methylome when replication-coupled maintenance is severely impaired.However,solo-WCGW sites and other CpG sites displaying aging-and cancer-associated hypomethylation exhibit low maintenance efficiency,suggesting that although quite robust,mitotic inheritance of methylation is imperfect and that this imperfection may contribute to selective hypomethylation during aging and tumorigenesis. | Xuan Ming Zhuqiang Zhang Zhuoning Zou Cong Lv Qiang Dong Qixiang He Yangyang Yi Yingfeng Li Hailin Wang Bing Zhu | 2020 | Cell Research2020，30，11： | 4 |
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