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    题名 作者 年代 出处 被引量
1OSCILLATION FOR SYSTEMS OF NONLINEAR NEUTRAL TYPE PARABOLIC PARTIAL FUNCTIONAL DIFFERENTIAL EQUATIONS显示文摘This paper discusses the oscillation of solutions for systems of nonlinear neutral type parabolic partial fuctional differential equations of theYANGJUN GUANXINPING 1997Applied Mathematics(A Journal of Chinese Universities)1997,12,2:23
2Ozone sensitivity analysis with the MM5-CMAQ modeling system for Shanghai显示文摘Ozone has become one of the most important air pollution issues around the world. This article applied both O 3 /(NOy-NOx) and H 2 O 2 /HNO 3 indicators to analyze the ozone sensitivity in urban and rural areas of Shanghai, with implementation of the MM5-CMAQ modeling system in July, 2007. The meteorological parameters were obtained by using the MM5 model. A regional emission inventory with spatial and temporal allocation based on the statistical data has been developed to provide input emission data to the MM5-CMAQ modeling system. Results showed that the ozone concentrations in Shanghai show clear regional differences. The ozone concentration in rural areas was much higher than that in the urban area. Two indicators showed that ozone was more sensitive to VOCs in urban areas, while it tended to be NOx sensitive in rural areas of Shanghai.Li Li Changhong Chen Cheng Huang Haiying Huang Gangfeng Zhang Yangjun Wang Minghua Chen Hongli Wang Yiran Chen D. G. Streets Jiamo Fu 2011Journal of Environmental Sciences2011,23,7:18
3青少年初始血压高者在高血压发生中的预测意义显示文摘为探讨初始血压偏高者在高血压发生中的预测意义,对汉中农村4623名年龄6~15岁青少年血压,经过8年随访(末次随访率为82.07%)证明,基线调查收缩压百分位与8年后的收缩压相关系数,男为0.33,女为0.28,舒张压均为0.20;基线调查收缩压在第75百分位(P75)以上者,8年后血压≥18.7/12.0kPa(140/90mmHg)的机率是LiuZhi-quan,YangJun,MuJianjun,etal.No.1AfiliatedHospitalofXi′anMedicalUniversity,Xi′an710061 1996中华心血管病杂志1996,24,4:18
4The effect of Helicobacter pylori infection on expression of macrophage migration inhibitory factor by T cells and macrophages in gastric mucosa显示文摘Background Macrophage migration inhibitory factor (MIF) plays a pivotal role in inflammatory and immune-mediated diseases. However, its molecular function and role in gastrointestinal diseases has rarely been studied and thus warrants an in-depth investigation. This study was designed and conducted to determine MIF expression in Helicobacter pylori (H. pylori)-induced gastritis and the effect of H. pylori on MIF expression in monocytes in vitro. Methods Gastric specimens of 62 patients with chronic gastritis were obtained through endoscopic biopsies. Both gastric antrum and body were examined for histopathologic changes. Positive H. pylori was determined through rapid urease test and histopathological examination. A patient was classified as H. pylori positive if both tests showed positive results. The updated Sydney System was employed to assess the severity and activity of gastric inflammation. Double immunoassaying for MIF/T-cells (CD45RO) and MIF/macrophage (KP1), as well as in situ hybridization for the expression of MIF mRNA were used for the current analysis. THP-1, a monocyte cell line, was co-incubated with H. pylori strains (ATCC26695) and subsequently examined for the expression of MIF protein and mRNA by enzyme linked immunosorbent assay and retrospective transcription-polymerase chain reaction, respectively. Results Among 62 patients with chronic gastritis, significant increase in total T-cells, MIF^+ T-cells, total macrophages, MIF^+ macrophages and MIF mRNA^+ cells was observed in 42 H. pylori positive patients compared to H. pylori negative patients. Moreover, the increase of the MIF mRNA^+ cells was highly correlated with the severity of the disease(number of MIF mRNA^+cells/mm^2, mild: 2834±382, moderate: 3569±123, severe: 3881±118, P<0.01). In vitro results showed that the expression of MIF protein and mRNA in monocytes was significantly increased after incubation with H. pylori strains.Conclusions Overexpression of MIF is common in H. pylori-induced gastric inflammation, which suggests MIF may play an important role in the initiation and development of this disease.HEXing-xiang YANGJun ZHENGXue-ling DINGYuan-wei SHENQing-yan LIUWei ZHAOYing-heng 2005Chinese Medical Journal2005,,14:11
5Temperature pattern dynamics in shocked porous materials显示文摘The physical fields in porous materials under strong shock wave reaction are very complicated. We simulate such systems using the grain contact material point method. The complex temperature fields in the material are treated with the morphological characterization. To compare the structures and evolution of characteristic regimes under various temperature thresholds, we introduce two concepts, structure similarity and process similarity. It is found that the temperature pattern dynamics may show high similarity under various conditions. Within the same material, the structures and evolution of high-temperature regimes may show high similarity if the shock strength and temperature threshold are chosen appropriately. For process similarity in materials with high porosity, the required temperature threshold increases parabolically with the impact velocity. When the porosity becomes lower, the increasing rate becomes higher. For process similarity in different materials, the required temperature threshold and the porosity follow a power-law relationship in some range.XU AiGuo*, ZHANG GuangCai, LI Hua, YING YangJun, YU XiJun & ZHU JianShi National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China 2010Science China(Physics,Mechanics & Astronomy)2010,53,8:7
6Potassium Uptake and Transport in Apple Roots Under Drought Stress显示文摘As one of the most important mineral nutrient elements, potassium(K^+) plays an important role in many plant physiological processes and determines both the yield and quality of crops. There are two typical gene families that regulate K^+transport in higher plants, including K^+channels and K^+transporters. However, little is known about how these channels and transporters divide their work in response to drought stress. In this study, the hydroponic experiment was conducted on Malus hupehensis. The K^+content was found to decrease in response to drought stress in M. hupehensis, the aboveground decreased by 34.15% and the underground decreased by 3.97%. Meanwhile, the root morphology change was detected by scanning the root system. Under conditions of drought, the genes encoding K^+transporters were upregulated including MdCHX1.3, MdCHX4.11, MdCHX4.8, MdCHX4.9, Md HKT1, and MdHAK3.2. The net influx of K^+was inhibited by 19.47% with the action of K^+channel inhibitors(CsCl), however a significant decrease(80.99%; P < 0.05) was found in roots exposed to a PM H+-ATPase(orthovanadate) inhibitor by utilizing a non-invasive micro-test technique. The trend of H+efflux was similar to that of K^+. The data suggested that the positive influx of K^+through the transporter accounted for the main K^+uptake under drought stress. These results suggest that we can improve the uptake of K^+by purposely up-regulating specific K^+transporters under drought stress. This process may improve growth, yield, quality, and stress tolerance in apple trees.Jianguo Qi Simin Sun Lin Yang Mingjun Li Fengwang Ma Yangjun Zou 2019Horticultural Plant Journal2019,5,1:6
7A Genomic Variation Map Provides Insights into the Genetic Basis of Spring Chinese Cabbage (Brassica rapa ssp.pekinensis)Selection显示文摘Chinese cabbage is the most consumed leafy crop in East Asian countries.However,premature bolting induced by continuous low temperatures severely decreases the yield and quality of the Chinese cabbage, and therefore restricts its planting season and geographic distribution.In the past 40years,spring Chinese cabbage with strong winterness has been selected to meet the market demand.Here,we report a genome variation map of Chinese cabbage generated from the resequencing data of 194 geographically diverse accessions of three ecotypes.In-depth analyses of the selection sweeps and genome-wide patterns revealed that spring Chinese cabbage was selected from a specific population of autumn Chinese cabbage around the area of Shandong peninsula in northern China.We identified 23 genomic loci that underwent intensive selection,and further demonstrated by gene expression and haplotype analyses that the incorporation of elite alleles of VERNALISATION INSENTIVE 3.1(BrVIN3.1)and FLOWER LOCUS C 1(BrFLC1)is a determinant genetic source of variation during selection.Moreover,we showed that the quantitative response of BrVIN3.1 to cold due to the sequence variations in the cis elements of the BrVlN3.1 promoter significantly contributes to bolting-time variation in Chinese cabbage.Collectively, our study provides valuable insights into the genetic basis of spring Chinese cabbage selection and will facilitate the breeding of bolting-resistant Varieties by molecular-marker-assisted selection,transgenic or gene editingapproaches.Tongbing Su Weihong Wang Peirong Li Bin Zhang Pan Li Xiaoyun Xin Honghe Sun Yangjun Yu Deshuang Zhang Xiuyun Zhao Changlong Wen Gang Zhou Yuntong Wang Hongkun Zheng Shuancang Yu Fenglan Zhang 2018Molecular Plant2018,11,11:6
8Research and development on transonic compressor of high pressure ratio turbocharger for vehicle internal combustion engines显示文摘The pressure ratio required for a turbocharger centrifugal compressor increases with internal combustion engine power density. High pressure ratio causes a transonic flow field at the impeller inducer. Transonic flow narrows the stable flow range and de-teriorates stage efficiency. In this work, an advanced high pressure ratio transonic compressor was designed. The experimental results show that the maximum pressure ratio of this turbocharger is about 4.2, the maximum efficiency is above 80% and the stable flow range at the designed rotating speed is up to 34%. A turbocharger with this transonic compressor has been applied to some vehicle research actually, and improved power density by 40%.ZHENG XinQian, ZHANG YangJun & YANG MingYang State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China 2010Science China(Technological Sciences)2010,53,7:6
9Study on self-healing and corrosion resistance behaviors of functionalized carbon dot-intercalated graphene-based waterborne epoxy coating显示文摘Functionalized carbon dots(CDs)obtained from citric acid derivative were selected as intercalatorto modify graphene and then dispersed into epoxy matrix to prepare CDs modified graphene/epoxy(CDs-G/EP)coatings.Meanwhile,their microstructure,self-healing and corro sion resistance behaviors were analyzed deeply.Structural characterizations indicated the formation of'π-π'interaction between functionalized carbon dots and graphene.By observation,the dispersion and interface compatibility of graphene were greatly enhanced by CDs.The change rules of electrochemistry results implied that the addition of 0.5 wt.%CDs-G in EP coating(CDs-G0.5%/EP)demonstrated a superior protective property on steel,which was attributed to the physical barrier of highly dispersed graphene and the self-healing ability of CDs.After 50 days immersion,the oxygen permeability coefficient and water absorption of CDs-G0.5%/EP coating were only 4.27×10^(-13)cm^(3)cm cm^(-2)s^(-1)Pa^(-1) and 4.4%,respectively.Yuwei Ye Hao Chen Yangjun Zou Haichao Zhao 2021Journal of Materials Science & Technology2021,,8:5
10Adaptive Robust Filtering Algorithm for BDS Medium and Long Baseline Three Carrier Ambiguity Resolution显示文摘For classical TCAR(three carrier ambiguity resolution)algorithm is affected by ionospheric delay and measurement noise,it is difficult to reliably fix ambiguity at medium and long baselines.An improved TCAR algorithm which takes the influence of ionospheric delay into account and has good adaptive robustness is proposed.On the basis of the non-geometric TCAR model,ionospheric delay is obtained by linearly combining extra-wide-lane with fixed ambiguity,and then wide-lane ambiguity is solved.Solving narrow-lane ambiguity by adaptive robust filtering by constructing optimal combination observation,which can effectively improve the fixed success rate of narrow-lane ambiguity and reduce the adverse effects of gross error.Experimental results show that the improved TCAR algorithm can guarantee a high fixed correct rate of wide-lane ambiguity,effectively improve fixed success rate of narrow-lane ambiguity,and has a good ability to resist gross error.Yangjun GAO Zhiwei LV Pengjin ZHOU Zhengyang JIA Lundong ZHANG Dianwei CONG 2020Journal of Geodesy and Geoinformation Science2020,3,2:5
11Methods for predicting the remaining useful life of equipment in consideration of the random failure threshold显示文摘The value range of the failure threshold will generate an uncertain influence on the prediction results for the remaining useful life(RUL) of equipment. Most of the existing studies on the RUL prediction assume that the failure threshold is a fixed value,as they have difficulty in reflecting the random variation of the failure threshold. In connection with the inadequacies of the existing research, an in-depth analysis is carried out to study the effect of the random failure threshold(RFT) on the prediction results for the RUL. First, a nonlinear degradation model with unit-to-unit variability and measurement error is established based on the nonlinear Wiener process. Second, the expectation-maximization(EM) algorithm is used to solve the estimated values of the parameters of the prior degradation model, and the Bayesian method is used to iteratively update the posterior distribution of the random coefficients. Then, the effects of three types of RFT constraint conditions on the prediction results for the RUL are analyzed, and the probability density function(PDF) of the RUL is derived. Finally,the degradation data of aero-turbofan engines are used to verify the correctness and advantages of the method.WANG Zezhou CHEN Yunxiang CAI Zhongyi GAO Yangjun WANG Lili 2020Journal of Systems Engineering and Electronics2020,31,2:5
12A Bayesian Updating Method for Non-Probabilistic Reliability Assessment of Structures with Performance Test Data显示文摘For structures that only the predicted bounds of uncertainties are available,this study proposes a Bayesianmethod to logically evaluate the nonprobabilistic reliability of structures based on multi-ellipsoid convex model and performance test data.According to the given interval ranges of uncertainties,we determine the initial characteristic parameters of a multi-ellipsoid convex set.Moreover,to update the plausibility of characteristic parameters,a Bayesian network for the information fusion of prior uncertainty knowledge and subsequent performance test data is constructed.Then,an updated multi-ellipsoid set with the maximum likelihood of the performance test data can be achieved.The credible non-probabilistic reliability index is calculated based on the Kriging-based surrogate model of the performance function.Several numerical examples are presented to validate the proposed Bayesian updating method.Jiaqi He Yangjun Luo 2020Computer Modeling in Engineering & Sciences2020,,11:5
13Robust topology optimization of hinge-free compliant mechanisms with material uncertainties based on a non-probabilistic field model显示文摘This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties,which are described using a non-probabilistic bounded field model.Bounded field uncertainties are efficiently represented by a reduced set of uncertain-but-bouncled coeflficients on the basis of the series expansion method.Robust topology optimization of compliant mechanisms is then defined to minimize the variation in output displacement under constraints of the mean displacement and predefined material volume.The nest optimization problem is solved using a gradient-based optimization algorithm.Numerical examples are presented to illustrate the effectiveness of the proposed method for circumventing hinges in topology optimization of compliant mechanisms.Junjie ZHAN Yangjun LUO 2019Frontiers of Mechanical Engineering2019,14,2:5
14Complex fields in heterogeneous materials under shock:modeling, simulation and analysis显示文摘In this mini-review we summarize the progress of modeling, simulation and analysis of shock responses of heterogeneous materials in our group in recent years. The basic methodology is as below. We first decompose the problem into different scales. Construct/Choose a model according to the scale and main mechanisms working at that scale. Perform numerical simulations using the relatively mature schemes. The physical information is transferred between neighboring scales in such a way: The statistical information of results in smaller scale contributes to establishing the constitutive equation in larger one. Except for the microscopic Molecular Dynamics(MD) model, both the mesoscopic and macroscopic models can be further classified into two categories,solidic and fluidic models, respectively. The basic ideas and key techniques of the MD, material point method and discrete Boltzmann method are briefly reviewed. Among various schemes used in analyzing the complex fields and structures, the morphological analysis and the home-built software, GISO, are briefly introduced. New observations are summarized for scales from the larger to the smaller.AiGuo Xu GuangCai Zhang YangJun Ying Cheng Wang 2016Science China(Physics,Mechanics & Astronomy)2016,59,5:4
15Linkage map and QTL mapping of red flesh locus in apple using a R1R1×R6R6 population显示文摘The red flesh in apple fruit is a desired trait by consumers and it is associated to the anthocyanin content,which is mainly controlled by MdMYB10 with a R6 promoter.In this study,a high-density linkage group was constructed using the‘Fuji’x‘Red3’population which contained homozygous alleles R1R1 and R6R6,respectively.The linkage group consists of 7630 SNPs along 17 linkage groups,spanning 2270.21 cM,with an average density of 0.30 cM permarker.The cyanidin-3-galactoside concentration was used as the phenotypic data in QTL analysis.Moreover,one QTL peak which was flaked by two markers,marker2187260 to marker2173766,with LOD scores of 4.49 was detected.This QTL ranged from 0 to 40.79 cM on the top of linkage group(LG16).In addition one candidate molecular marker(marker2175442)in this QTL was identified,which was significant correlated with the flesh cyanidin-3-galactoside concentration.These genetic findings enrich the breeding basis of fruit flesh coloration in apple.Chengquan Yang Guangya Sha Tao Wei Baiquan Ma Cuiying Li Pengmin Li Yangjun Zou Lingfei Xu Fengwang Ma 2021Horticultural Plant Journal2021,7,5:4
16Predictions of NOx/N2O emissions from an ultra-supercritical CFB boiler using a 2-D comprehensive CFD combustion model显示文摘NOx and N2O emissions from an ultra-supercritical circulating fluidized bed(CFB)boiler were predicted using a two dimensional(2-D)comprehensive computational fluid dynamics(CFD)combustion model.This model was developed from a three dimensional model for a supercritical CFB boiler previously constructed by our group.Based on an analysis of the NOx and N2O conversion processes in a CFB boiler,the primary formation and destruction reactions were introduced into the 2-D model and coupled.The resulting model was validated using data from the Baima 600 MW supercritical CFB boiler,and then applied to a 660 MW ultra-supercritical CFB boiler.The effects of excess air,the secondary air(SA)to(primary air(PA)plus SA)ratio and the SA injection height on NOx and N2O emissions were investigated.The results show that a higher excess air volume increases both NOx and N2O emissions,while increasing the SA/(PA+SA)ratio somewhat reduces both the NOx and N2O concentrations.On the basis of the results of this work,optimal locations for SA injection ports so as to lower NOx and N2O emissions are recommended.Jieqiang Ji Leming Cheng Yangjun Wei Junfeng Wang Xinyu Gao Mengxiang Fang Qinhui Wang 2020Particuology2020,18,2:4
17The improved FASTmrEMMA and GCIM algorithms for genome-wide association and linkage studies in large mapping populations显示文摘Owing to high power and accuracy and low false positive rate in our multi-locus approaches for genome-wide association studies and linkage analyses,these approaches have attracted considerable attention in plant and animal genetics.In large mapping population,however,fast multi-locus random-SNP-effect efficient mixed model association(FASTmrEMMA)and genome-wide composite interval mapping(GCIM)run a relatively long time.To address this issue,we proposed the improved FASTmrEMMA and GCIM algorithms in this study.In the new algorithms,some matrix identities,such as the Woodbury matrix identity,were used.In scanning each marker on the entire genome,in other words,the improved algorithms effectively replace the expensive eigenvector solutions in(restricted)maximum likelihood estimations in original algorithms with two(one)updated inner products and one updated vector-matrix-vector multiplication.Simulated and real data analyses showed that their computational efficiencies are increased sharply in large mapping population,although there are no mapping result differences between original and improved algorithms.In addition,the related software packages(mrMLM.GUI and QTL.gCIMapping.GUI)can be downloaded from the R and BioCode websites.Yangjun Wen Yawen Zhang Jin Zhang Jianying Feng Yuanming Zhang 2020The Crop Journal2020,8,5:4
18Optical limiting effect based on stimulated Brillouin scattering in CCl4显示文摘The optical limiting effect based on stimulated Brillouin scattering(SBS) in a nonlinear medium was investigated. We numerically treated the nonlinear propagation process with a theoretical model, which includes the spontansous nature of the initiation of SBS, and obtained optical limiting effect in the process. Energy limiting,pulse reshaping and stabilization have been demonstrated on SBS mechanism with the nonlinear medium CCl4. The input optical signals were Nd:YAG nanosecond laser pulses with width varying from 16ns to 7ns then to 2ns, the relationship between the transmitted signal and launched pump signal was shown. In the experimental regime, the most stable pulse the transmitted signal and launched pump signal was shown. In the experimental regime, the most stable pulse and a superior energy stabilization of the transmitted pulse were obtained when the laser pulse-width became as short as 2ns. For the energy variation of laser pulses in a wide range of 14-88mJ, the output energy was limited in a quite narrow range 4.5-5.5mJ.LueZhi-Wei LueYue-Lan YangJun 2003Chinese Physics B2003,12,5:3
19Improving the performance of ducted fans for VTOL applications:A review显示文摘Ducted fans have been widely used in VTOL aircraft due to the high propulsion efficiency and safety.The efficiency and stability of ducted fans deteriorate in some flight conditions such as hovering in crosswinds or ground effect.It is necessary to optimize the ducted fan’s structures or apply flow control methods for better adaptions to the typical conditions.This paper presents a detailed review on the ducted fan technology for VTOL applications,especially the methods for improving its efficiency and stability.We first simplified the classification categories based on boundary conditions instead of flight conditions,since the new classification method covers more situations and is easier to distinguish flow field characteristics.The flow characteristics,thrust properties and the optimal structures under different boundary conditions were summarized and discussed.Finally,new configurations and flow control methods for increasing the efficiency and stability were introduced.The newly proposed integration design between the ducted fan and the motor was emphasized for increasing the power density of the ducted fans.This review would be helpful to improve our understanding of the relationship between the structures,flow characteristics and thrust properties of ducted fans under different flight conditions,and inspires scientists to design high-efficiency and high-stability propulsion systems with ducted fans.QIAN YuPing LUO YiWei HU XuanYang ZENG ZeZhi ZHANG YangJun 2022Science China(Technological Sciences)2022,65,11:3
20Evaluation of the inhibition behavior of carbon dots on carbon steel in HCl and NaCl solutions显示文摘An eco-friendly and effective corrosion inhibitor(N-CDs)was acquired by hydrothermal method in methacrylic acid and ethyl(methyl)amine precursors.Afterwards,the weight loss and electrochemistry measurement were chosen to appraise the corrosion inhibition behavior of as-prepared N-CDs for Q235 steel in Cl-contained solutions.The change rules of EIS and Tafel data displayed that the as-prepared N-CDs revealed a high-efficiency protection for steel in all test environments.Meanwhile,the inhibition efficiency of steel reached up to 93.93%(1 M HCl)and 88.96%(3.5 wt%Na Cl)at 200 mg/L of N-CDs.Furthermore,the N-CDs could form the adsorption film on steel surface to avoid the strong attack of Cl-.By analysis,the adsorption mechanism of as-prepared N-CDs on steel surface was physicochemical interaction,which strictly complied with the Langmuir adsorption model in both solutions.Yuwei Ye Zilong Jiang Yangjun Zou Hao Chen Shengda Guo Qiumin Yang Liyong Chen 2020Journal of Materials Science & Technology2020,36,8:3
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