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1Optimal guidance against active defense ballistic missiles via differential game strategies显示文摘The optimal guidance problem for an interceptor against a ballistic missile with active defense is investigated in this paper.A class of optimal guidance schemes are proposed based on linear quadratic differential game method and numerical solution of Riccati differential equation.By choosing proper parameters, the proposed guidance schemes are able to drive the interceptor to the target and away from the defender simultaneously.Additionally, fuel cost, control saturation,chattering phenomenon and parameters selection were taken into account.Satisfaction of the proposed guidance schemes of the saddle point condition is proven theoretically.Finally, nonlinear numerical examples are included to demonstrate the effectiveness and performance of the developed guidance approaches.Comparison of control performance between different guidance schemes are presented and analysis.Haizhao LIANG Jianying WANG Yonghai WANG Linlin WANG Peng LIU 2020Chinese Journal of Aeronautics2020,33,3:12
2Simulation of Quasi-Linear Mesoscale Convective Systems in Northern China:Lightning Activities and Storm Structure显示文摘Two intense quasi-linear mesoscale convective systems(QLMCSs) in northern China were simulated using the WRF(Weather Research and Forecasting) model and the 3D-Var(three-dimensional variational) analysis system of the ARPS(Advanced Regional Prediction System) model.A new method in which the lightning density is calculated using both the precipitation and non-precipitation ice mass was developed to reveal the relationship between the lightning activities and QLMCS structures.Results indicate that,compared with calculating the results using two previous methods,the lightning density calculated using the new method presented in this study is in better accordance with observations.Based on the calculated lightning densities using the new method,it was found that most lightning activity was initiated on the right side and at the front of the QLMCSs,where the surface wind field converged intensely.The CAPE was much stronger ahead of the southeastward progressing QLMCS than to the back it,and their lightning events mainly occurred in regions with a large gradient of CAPE.Comparisons between lightning and non-lightning regions indicated that lightning regions featured more intense ascending motion than non-lightning regions;the vertical ranges of maximum reflectivity between lightning and non-lightning regions were very different;and the ice mixing ratio featured no significant differences between the lightning and non-lightning regions.Wanli LI Xiushu QIE Shenming FU Debin SU Yonghai SHEN 2016Advances in Atmospheric Sciences2016,33,1:7
3Low-frequency sea level variation and its correlation with climate events in the Pacific显示文摘Global mean sea level(GMSL) has not only significant secular trend and seasonal variations,but also inter-annual and decadal variations.This paper reconstructs the time series of GMSL variations between 1948 and 2007 by combining satellite altimeter measurements and tide gauge observations.Based on the time series,the acceleration of GMSL rise in the second half of 20th century is estimated to be 0.010±0.009 mm/a 2,and multi-scale low frequency sea level oscillations including decadal variations are detected,and the high-rate of GMSL rise during 1993-2003 is locate in the ascending phase of low frequency oscillation.Then,using the reconstructed GMSL time series after removing the secular trend from satellite altimetry and tide gauges measurements,it shows that low frequency signal of sea level variation has strong correlations with the index of El Ni o/Southern Oscillation(ENSO) and Pacific Decadal Oscillation(PDO).But in several time periods,they have large difference due to effects of both high frequency occurrence of El Ni o and La Ni a phenomenon and short term switch of PDO events.JIN TaoYong LI JianCheng JIANG WeiPing CHU YongHai 2012Chinese Science Bulletin2012,57,27:6
4FriedeI-Crafts Alkylation of Indoles with Nitroalkenes Catalyzed by Zn(II)-Thiourea Complex显示文摘Wan,Ningning Hui,Yonghai Xie,Zhengfeng Wang,Jide 2012Chinese Journal of Chemistry2012,30,2:6
5Functional Diversity of CYCLOIDEA-like TCP Genes in the Control of Zygomorphic Flower Development in Lotus japonicus显示文摘CYCLOIDEA (CYC)-like TCP genes play key roles in dorsoventral differentiation of zygomorphic flowers in Papilionoideae legumes. In this study, we analyzed the kew mutants whose flowers lost lateral identity, and investigated the diverse functions of three LjCYC genes during zygomorphic flower development in the model legume Lotus japonicus. We showed that kew1 and kew3 are allelic mutants of LjCYC3, a CYC-like TCP gene. Through transgenic experiments, it was shown that LjCYC1 possesses dorsal activity similar to LjCYC2, and that LjCYC3 alone is sufficient to confer lateral activity, and an epistatic effect between dorsal and lateral activities was identified. Sequence analysis revealed a striking alteration at the 3 end of the LjCYC3 open reading frame (ORF) in comparison with those of LjCYC1 and LjCYC2 ORFs. Furthermore, it was found that LjCYC proteins could interact with each other and possess different activities by means of a transcriptional activity assay. Our data demonstrate that the sequence variation and the subsequent alteration of protein property play important roles in the functional diversity of different LjCYC genes in controlling zygomorphic flower development in Lotus japonicus.Shilei Xu Yonghai Luo Zhigang Cai Xiangling Cao Xiaohe Hu Jun Yang Da Luo 2013Journal of Integrative Plant Biology2013,55,3:6
6Preparation of nitrogen and sulfur co-doped ultrathin graphitic carbon via annealing bagasse lignin as potential electrocatalyst towards oxygen reduction reaction in alkaline and acid media显示文摘Renewable lignin used for synthesizing materials has been proven to be highly potential in specific electrochemistry.Here,we report a simple method to synthesize nitrogen and sulfur co-doped carbon nanosheets by using bagasse lignin,denoted as lignin-derived carbon(LC).By adjusting the ratio of nitrogen source and annealing temperature,we obtained the ultrathin graphitic lignin carbon(LC-4-1000)with abundant wrinkles with high surface area of 1208 m2g_1 and large pore volume of 1.40 cm3g_1.In alkaline medium,LC-4-1000 has more positive half-wave potential and nearly current density compared to commercial Pt/C for oxygen reduction reaction(ORR).More importantly,LC-4-1000 also exhibits comparable activity and superior stability for ORR in acid medium due to its high graphitic N ratio and a direct four electron pathway for ORR.This study develops a cost-effective and highly efficient method to prepare biocarbon catalyst for ORR in fuel cells.Yixing Shen Feng Peng Yonghai Cao Jianliang Zuo Hongjuan Wang Hao Yu 2019Journal of Energy Chemistry2019,28,7:5
7Proportional Fairness-Based Energy-Efficient Power Allocation in Downlink MIMO-NOMA Systems with Statistical CSI显示文摘In this paper, proportional fairness(PF)-based energy-efficient power allocation is studied for multiple-input multiple-output(MIMO) non-orthogonal multiple access(NOMA) systems. In our schemes, statistical channel state information(CSI) is utilized for perfect CSI is impossible to achieve in practice. PF is used to balance the transmission efficiency and user fairness. Energy efficiency(EE) is formulated under basic data rate requirements and maximum transmitting power constraints. Due to the non-convex nature of EE, a two-step algorithm is proposed to obtain sub-optimal solution with a low complexity. Firstly, power allocation is determined by golden section search for fixed power. Secondly total transmitting power is determined by fractional programming method in the feasible regions. Compared to the performance of MIMO-NOMA without PF constraint, fairness is obtained at expense of decreasing of EE.Yonghai Lin Zhen Yang Haiyan Guo 2019China Communications2019,16,12:5
8Study on Compressive Properties of Z-pinned Laminates in RTD and Hygrothermal Environment显示文摘Compressive tests of [0] 12 and [90] 12 unidirectional laminates and [45/0/-45/90] 2S quasi-isotropic laminates are accomplished in both room-temperature and dry (RTD) and hygrothermal environment. And simulation studies on the compressive strength of Z-pinned laminates of [0] 12 and [45/0/-45/90] 2S are conducted by using finite element analysis (FEA). A microstructural unit cell for FEA is created to simulate a representative laminates unit with one pin. Within the unit cell, the first directions of the elements’ material coordinate systems are changed to simulate the fibres’ deflecting around the pin. The hygrothermal effect is simulated by the material properties’ adjustments which are determined by the compressive tests of non-pined laminates. The experimental results indicate that the percentage of reduction in the compressive modulus of Z-pinned laminates caused by Z-pin becomes smaller with the percentage of 0° fibres decreasing in the laminates; the compressive strength of quasi-isotropic laminates reduces and the percentage of the reduction in the compressive strength declines with Z-pin volume content increasing, and the moisture absorption ratio of the Z-pinned specimens is greater than that of the non-pinned specimens, because the cracks around Z-pin increase the moisture absorption. In addition, the simulations show that the deflection of fibres around Z-pin is the main factor for the reduction in the compressive strength of Z-pinned unidirectional laminates, the dilution of fibre volume content caused by resin-rich pocket is the principal factor for the decline in the compressive strength of Z-pinned quasi-istropic laminates, and the compressive strength of Z-pinned specimens in hygrothermal environment reduces as the result of superimposition of some factors, including the changes in material properties caused by hygrothermal environment, the deflection of fibres and the resin-rich pocket caused by Z-pin.LI Chenghu YAN Ying WANG Ping QI Desheng WEN Yonghai 2012Chinese Journal of Aeronautics2012,25,1:4
9Serum osmolality and ions,and gill Na^(+)/K^(+)-ATPase of spottedtail goby Synechogobius ommaturus(R.)in response to acute salinity changes显示文摘This study was carried out to determine the effects of abrupt salinity change on osmoregulatory ability of the spottedtail goby Synechogobius ommaturus.720 juvenile fish(65.3±11.8 g)were transferred to 200 L tanks(with 40 juveniles in each tank),in which salinities were abruptly changed from 10 to 20,30,40,50 and freshwater.Survival rate,serum osmolality,electrolytes(Na^(+),Cl^(-),and K^(+))and gill Na^(+)/K^(+)-ATPase(NKA)activity were assessed successively in 528 h.Results showed serum osmolality,ion concentrations and gill Na^(+)/K^(+)-ATPase activity increased significantly when fish were transferred to salinity 40 and 50 and all fish in these groups died by the end of the experiment.Serum osmolality,Na^(+),Cl^(-)and K^(+)in fish transferred to a salinity of 20,30 and freshwater were not affected and no mortality was detected.Compared with the control group,a significantly decrease of NKA activity happened in the freshwater group,but the activity in 20 and 30 groups was not affected significantly.The results indicated that S.ommaturus could adapt rapidly and maintain homeostasis in a wide range of salinities(from freshwater to salinity 30)and this species may be suitable for aquaculture in estuarine and coastal areas where rapid salinity fluctuations commonly occur.Chun Shui Yonghai Shi Xueming Hua Zhonghua Zhang Haiming Zhang Genhai Lu Yongde Xie 2018Aquaculture and Fisheries2018,3,2:4
10Kinetic granular temperature and its measurement using speckle visibility spectroscopy显示文摘The occurrence of a mesoscopic scale in granular materials leads to a sharp increase in the number of interaction processes at both intra-and inter-scale levels.The mesoscopic scale is the main source of the complex macroscopic properties of granular materials.The quantification of mesoscopic disordered movements is often referred to as granular temperature.In this paper,we first introduce the physical meaning of the original granular temperature of a kinetic nature,Tk,and then briefly summarize the advances made over the past few decades.Our research group has focused on Tk measurement using speckle visibility spectroscopy.The principle of this technique and the instruments developed in our research group are briefly introduced.Our work shows great promise in the measurement of kinetic granular temperature.Finally,a summary of granular temperature and some recent developments in speckle visibility spectroscopy measurements are presented.Hui Yang Yonghai Zhu Ran Li Qicheng Sun 2020Particuology2020,18,1:4
11Reduced grain chalkiness and its possible physiological mechanism in transgenic rice overexpressing L-GalLDH显示文摘Chalkiness is one of the key factors determining rice quality and price. Ascorbic acid(Asc) is a major plant antioxidant that performs many functions in plants. L-Galactono-1,4-lactone dehydrogenase(L-Gal LDH, EC1.3.2.3) is an enzyme that catalyzes the final step of Asc biosynthesis in plants. Here we show that the L-Gal LDH-overexpressing transgenic rice, GO-2,which has constitutively higher leaf Asc content than wild-type(WT) plants, exhibits significantly reduced grain chalkiness. Higher foliar ascorbate/dehydroascorbate(Asc/DHA)ratios at 40, 60, 80, and 100 days of plant age were observed in GO-2. Further investigation showed that the enhanced level of Asc resulted in a significantly higher ribulose-1,5-bisphosphate(Ru BP) carboxylase/oxygenase(Rubisco) protein level in GO-2 at 80 days. In addition, levels of abscisic acid(ABA) and jasmonic acid(JA) were lower in GO-2 at 60, 80, and100 days. The results we present here indicate that the enhanced level of Asc is likely responsible for changing redox homeostasis in key developmental stages associated with grain filling and alters grain chalkiness in the L-Gal LDH-overexpressing transgenic by maintaining photosynthetic function and affecting phytohormones associated with grain filling.Le Yu Yonghai Liu Jianhua Tong Junhui Ding Ruozhong Wang Changlian Peng Langtao Xiao 2015The Crop Journal2015,3,2:4
12Effect of Hydraulic Loading Rate on the Efficiency of Effluent Treatment in a Recirculating Puffer Aquaculture System Coupled with Constructed Wetlands显示文摘Constructed wetlands(CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer(Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate(HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions(salinity 7.4–7.6) at 3 different HLRs(0.762, 0.633, and 0.458 m d–1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen(by 81.03–92.81%) and nitrite nitrogen(by 99.40%–99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids(TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.XU Jiabo SHI Yonghai ZHANG Genyu LIU Jianzhong ZHU Yazhu 2014Journal of Ocean University of China2014,13,1:3
13Oxidation of unsymmertrical disulfide and thiosulfinics esters with peroxy acids 显示文摘Shigern Oae Takata Yonghai Kim 1982BullChem Sou J pn1982,55,8:3
14Analysis for remedial alternatives of unregulated municipal solid waste landfills leachate-contaminated groundwater显示文摘地下水流动和溶质运输模型为预报沾染物运输并且基于 unregulated 垃圾堆的案例研究估计补救选择的效果用视觉 Modflow 被开发在东方中国的污染 leachate 的地下水。结果证明那根砷羽毛是到达在八年,和砷羽毛的最长侧面、纵的距离以后在下游的农田抽很好是分别地到达 200 m 和 260 m。但是砷羽毛的区域是不显然从八年增加到十年和羽毛的高集中的区域是在 20 年以后传播到下游的河和农田区域;当垃圾堆磨擦了时被变硬,羽毛是不在八年以后到达下游的农田区域;当抽的井下游地在羽毛被安装,分泌物率是 200m ^ 时,啜 3 ^/d,羽毛将有效地被制止;为防漏的障碍,它可能有效地在一个程度时间范围以内保护敏感目标的地下水。要不是连续的点来源,羽毛仍然是防漏的障碍到圆;当排水阴沟的分泌物率是 170.26 m ^ 时,啜 3 ^/d,羽毛有效地被控制;有排水阴沟的联合地面变硬能在控制沾染物散开给最好的效果的全面方法,和分泌物率将被归结为 111.43 m ^ 啜 3 ^/d。因此,当 leachate 漏发生在 unregulated 垃圾堆时,有排水阴沟的全面补救其他的联合地面变硬将为阻止地下水污染被推荐[出版摘要]Da AN Yonghai JIANG Beidou XI Zhifei MA Yu YANG Queping YANG Mingxiao LI Jinbao ZHANG Shunguo BAI Lei JIANG 2013Frontiers of Earth Science2013,7,3:3
15Systematic centroid error compensation for the simple Gaussian PSF in an electronic star map simulator显示文摘Simulated star maps serve as convenient inputs for the test of a star sensor, whose standardability mostly depends on the centroid precision of the simulated star image, so it is necessary to accomplish systematic error compensation for the simple Gaussian PSF(or SPSF, in which PSF denotes point spread function). Firstly, the error mechanism of the SPSF is described, the reason of centroid deviations of the simulated star images based on SPSF lies in the unreasonable sampling positions(the centers of the covered pixels) of the Gaussian probability density function. Then in reference to the IPSF simulated star image spots regarded as ideal ones, and by means of normalization and numerical fitting, the pixel center offset function expressions are got, so the systematic centroid error compensation can be executed simply by substituting the pixel central position with the offset position in the SPSF. Finally, the centroid precision tests are conducted for the three big error cases of Gaussian radius r = 0.5, 0.6, 0.671 pixel, and the centroid accuracy with the compensated SPSF(when r = 0.5) is improved to 2.83 times that of the primitive SPSF, reaching a 0.008 pixel error, an equivalent level of the IPSF. Besides its simplicity, the compensated SPSF further increases both the shape similarity and the centroid precision of simulated star images, which helps to improve the image quality and the standardability of the outputs of an electronic star map simulator(ESS).Wang Haiyong Wang Yonghai Li Zhifeng Song Zhenfei 2014Chinese Journal of Aeronautics2014,27,4:3
16Optical bandgap energy of CH3NH3PbI3 perovskite studied by photoconductivity and reflectance spectroscopy显示文摘Organic-inorganic hybrid perovskite materials have been receiving considerable attention due to their promising applications in many optoelectronic fields. However, the optical bandgap of CH_3NH_3PbI_3 perovskite is still disputed. In order to comprehend the intrinsic characteristics of these materials, we study the near-band-edge optical responses of the solution-processed CH_3NH_3PbI_3 perovskite crystals by photoconductivity and reflectance spectroscopy at room temperature. All these spectra of the CH_3NH_3PbI_3 polycrystals show only one significant absorption edge at 1.58 eV. However, we observe an extra absorption edge at 1.47 eV in CH_3NH_3PbI_3 single crystal. We establish a simple kinetic model of charge annihilation processes to explain why the low-energy structure of the photoconductivity and diffuse reflectance spectra of CH_3NH_3PbI_3 polycrystals disappear, which provides another possibility for understanding the difference in absorption edge. It is noteworthy that this low-energy absorption edge of CH_3NH_3PbI_3 single crystal has, to the best of our knowledge, seldom been reported on organic-inorganic hybrid perovskites.Therefore, the CH_3NH_3PbI_3 single crystal exhibits a relatively wide absorption which makes it a promising candidate for photoelectric applications.HUANG Wei LIU Yu YUE ShiZhong ZHU LaiPan JIN Peng WU Qing ZHANG Yang QU ShengChun WANG ZhiJie CHEN YongHai 2018Science China(Technological Sciences)2018,61,6:3
17InAs-based interband cascade lasers at 4.0 μm operating at room temperature显示文摘InAs-based interband cascade lasers(ICLs) with InAs plasmon waveguides or InAs/AlSb superlattice(SL) waveguides were demonstrated at emission wavelengths below 4.1 μm. The threshold current densities of the lasers with SL waveguides were 37 A/cm^2 at 77 K in continuous wave mode. The operation temperature of these lasers reached room temperature in pulsed mode. Compared with the thick InAs n++ plasmon cladding layer, the InAs/AlSb superlattice cladding layers have greater advantages for ICLs with wavelengths less than 4 μm even in InAs based ICLs because in the short-wavelength region they have a higher confinement factor than InAs plasmon waveguides.Tian Yu Shuman Liu Jinchuan Zhang Bo Xu Lijun Wang Junqi Liu Ning Zhuo Shenqiang Zhai Xiaoling Ye Yonghai Chen Fengqi Liu Zhanguo Wang 2018Journal of Semiconductors2018,39,11:3
18Brain-derived neurotrophic factor genes transfect rat bone marrow mesenchymal stem cells based on cationic polymer vector显示文摘BACKGROUND: Gene therapy is an effective expression of genes within target cells after transferring exogenous target genes. Both vector selection and transfection method are important factors for gene transfection. An ideal gene vector is required for a high transfusion of target gene and an exact introduction of target gene into specific target cells so as to express gene products. OBJECTIVE: To study the expression of mRNA and protein after transfecting rat bone marrow mesenchymal stem cells (BMSCs) with brain-derived neurotrophic factor (BDNF) genes based on cationic polymer vector. DESIGN, TIME AND SETTING: A randomized, controlled in vitro study using gene engineering, performed at the Neurobiology Laboratory, Xuzhou Medical College between October 2007 and April 2008. MATERIALS: PcDNA3.1 BDNF was obtained from Youbiai Biotechnological Company, Beijing and cationic polymer vector used was the SofastTM gene transfection reagent that was made by Taiyangma Biotechnological Co., Ltd., Xiamen. METHODS: BMSCs extracted from six Sprague Dawley (SD) rats aged 1 month were isolated and cultured in vitro. Third passage BMSCs were inoculated on a 6-well culture plate at the density of 1×106 cells/L. At about 80% confluence, BMSCs were transfected with PcDNA3.1-BDNF (2 μg) combined with SofastTM gene transfection reagent (6 μg) (BDNF group) or with PcDNA3.1 (2 μg) combined with SofastTM gene transfection reagent (6 μg) (blank vector group). Cells that were not transfected with any reagents but still cultured under primary culture conditions were used as a non-transfection group. MAIN OUTCOME MEASURES: Enzyme linked immunosorbent assay was used to measure time efficiency of BMSC-secreted BDNF protein. Twenty-four hours after gene transfection, RT-PCR was used to detect expression of BDNF mRNA in the BMSCs. Immunohistochemistry was used to determine expression of BDNF protein in the BMSCs. RESULTS: BDNF protein expression was detected at day 1 after gene transfection, rapidly increased after 5–9 days and gradually increased after 11–15 days in the BDNF group; moreover, BDNF protein expression was higher than that in the non-transfection group and the blank vector group at different time points (P < 0.01). Additionally, BDNF mRNA expression in the BDNF group was higher than that in the blank vector group and the non-transfection group (P < 0.01). CONCLUSION: A cationic polymer vector can effectively mediate the BDNF gene to transfect BMSCs; genetically modified BMSCs can express BDNF protein effectively for a long term.Zunsheng Zhang Kun Zan Yonghai Liu Xia Shen 2009Neural Regeneration Research2009,4,1:2
19Three-dimensional electrochemical process for wastewater treatment: a general review 显示文摘ZHAO Chao JIANG Yonghai LI Yulin 2013Chemical Engineering Journal2013,228,:1
20Didodecyldimethylammonium bromide lipid bilayer-protected gold nanoparticles:synthesis,characterization,and self-assembly显示文摘ZHANG Lixue SUN Xuping SONG Yonghai 2006Langmuir2006,22,6:1
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