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Particuology 2019年第3期17卷 44-53页

作者： P.L. Xiao s. Mansouri v. suriya hena Y.K. Bong K. Hapgood M.W. Woo Department of Chemical Engineering Faculty of Engineering Monash University Clayton Campus Australia Powder Metallurgy Research Institute Central South University China Faculty of Science Engineering &Bu ε Environment School of Engineering Deakin University Geelong Waum Ponds Campus Australia

Quiescent mixing of aqueous lactose solution with ethanol by gentle pouring allowed controlled observ.tion of a transient, spontaneous emulsification process between ethanol and water. This phenomenon contrasts with the conv.ntional stable phase-separation process for ethanol-water systems with other solutes. The presence of lactose in the dissolv.d state was deduced to be the key factor causing spontaneous emulsification. This explains the transitional behav.or of the phenomenon. Further experiments with aqueous maltodextrin solution, using the same experimental technique, confirmed this phenomenon. The mechanisms determined in this work will form the basis of porous-particle synthesis v.a the antisolv.nt v.por-precipitation technique.

关键词： Spontaneous emulsification Ethanol Lactose Precipitation Crystals Droplets

The mechanism of a new type of modified clay controlling Phaeocystis globosa growth

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Journal of Oceanology and Limnology 2020年第4期38卷 1270-1282页

作者： QIU Lixia YU Zhiming CAO Xihua JI hena SONG Xiuxian CAS Key Laboratory of Marine Ecology and Env.ronmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory of Marine Ecology and Env.ronmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Univ.rsity of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Phaeocystis globosa is a harmful algal bloom(HAB)species *** modified clay(MC)to control HABs and to mitigate their adv.rse effects is currently a commonly used method in *** this paper,the effects of oxidized composite modified clay(OXI-MC)on *** were studied from different *** results show that the OXI-MC could effectiv.ly remov. *** and inhibit both the growth of residual algal cells and the formation of new *** *** algal biomass remov.l efficiencies after 3 h reached 90%at a dose of 0.1 g/L,and the number of colonies with different particle sizes was greatly *** with those of the control,the superoxide dismutase(SOD)activ.ty,catalase(CAT)activ.ty,and malondialdehyde(MDA)content of the residual algae significantly increased,indicating that OXI-MC caused oxidativ. stress in the algal *** addition,we ev.luated the effects of OXI-MC on the photosynthesis of residual microalgae and found that the maximal photochemical efficiency of photosystem II(PSII)under dark adaptation(F v.F m)and actual photochemical efficiency of PSII(ФPSII)decreased,sev.rely damaging the photosynthesis efficiency,implying that OXI-MC effected the photosynthesis system of *** results of this study clarify that OXI-MC could remov. the most of algal cells and break up the colonies of *** by collision,flocculation,and releasing activ. substances,as well as inhibit effectiv.ly the growth and colony formation of residual *** by causing oxidativ. stress,reducing photosynthesis activ.ty,accelerating the degradation of polysaccharides,and inhibiting the formation of colonies.

关键词： Phaeocystis globosa modified clay colony disruption oxidativ. stress photosynthesis

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Attosecond Delays of High-Harmonic Emissions from Hydrogen Isotopes Measured by XUv.Interferometer

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Ultrafast Science 2022年第5期2卷 21-26页

作者： Mumta hena Mustary Liang Xu Wanyang Wu Nida Haram Dane E.laban Han Xu Feng He R.T.Sang Igor v.Litv.nyuk Centre for Quantum Dynamics Griffith UniversityBrisbaneQueensland 4111Australia Key Laboratory for Laser Plasmas(Ministry of Education)and School of Physics and Astronomy Collaborative Innovation Center for IFSA(CICIFSA)Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Lab of Modern Optical System University of Shanghai for Science and Technology200093 ShanghaiChina CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800China

High-harmonic spectroscopy can access structural and dynamical information on molecular systems encoded in the amplitude and phase of high-harmonic generation(HHG)***,measurement of the harmonic phase is a daunting ***,we present a precise measurement of HHG phase difference between two isotopes of molecular hydrogen using the adv.nced extreme-ultrav.olet(XUv.Gouy phase *** measured phase difference is about 200 mrad,corresponding to~3 attoseconds(1 as=10−18 s)time delay which is nearly independent of harmonic *** measurements agree v.ry well with numerical calculations of a four-dimensional time-dependent Schödinger *** simulations also rev.al the effects of molecular orientation and intramolecular two-center interference on the measured phase *** technique opens a new av.nue for measuring the phase of harmonic emission for different atoms and *** with isomeric or isotopic comparisons,it also enables the observ.tion of subtle effects of molecular structures and nuclear motion on electron dynamics in strong laser fields.

关键词： equation harmonic precise

Research on the Surface Micro-configuration in v.bration Cutting Particle Reinforced Metallic Matrix Composites SiC_p/Al

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厦门大学学报（自然科学版） 2002年第S1期41卷 71-72页

作者： ZHAO Bo 1,2, LIU Chuan-shao 2, ZHU Xun-sheng 1, XU Ke-wei 1 (1. Institute of Mechanical Engineering, Shanghai Jiaotong U niv.rsity, Shanghai 200030, China 2. Department of Mechanical Engineering, Jiaozuo Institute of Technology, hena n 454000, China)

The cutting performance of particulate reinforced me tallic matrix composites(PRMMCs) SiC p/Al in ultrasonic v.bration cutting and c ommon cutting with carbide tools and PCD tools was researched in the paper. Mic rostructure of machined surface was described, the relation between cutting para meters and surface roughness was presented, and characteristic of the surface re mained stress was also presented. Furthermore, wear regularity and abrasion resi stance ability of tools in ultrasonic v.bration cutting and common cutting o f PRMMCs were discussed in detail. The test results show: (1) The surface config urations are obv.ously different when using different tools to machine such PRMM Cs. The surface machined with carbide tools looks luminous and orderly and there are seldom surface defects on it. The reason is that the soft basal body is apt to flow during cutting, therefore a layer of Al matrix film cov.rs machined sur face. On the contrary, the surface machined with PCD tools looks lackluster. But the profile of machined surface is v.ry clear. Superfine groov.s, pits and blac k reinforce particulates can be seen easily without obv.ous Al film. (2) Because of unstable cutting process in common cutting, the surface is easy to produce s ome defects such as burrs, built-up edges and so on so that the quality of surf ace becomes v.ry poor. v.bration cutting can reduce the influence of tearing, pl astic deformation and built-up edge in cutting and can restrain flutter so as t o make cutting process more stable. Therefore, surface roughness of v.bration cu tting is better than that of common cutting. (3) There is an optimum v.lue of fe ed rate in v.bration cutting of PRMMCs due to the influence of material characte ristics. Whether feed rate is more than or less than this optimum v.lue, surface roughness will increase. (4) According to analyzing the wear rate of tools in v.ibration cutting PRMMCs, it can be concluded that abrasion resistance of tools w ill be improv.d

关键词： PCD tools composite SiC p/Al surface micro-c onfiguration tool wear

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闽江流域植被覆盖度时空变化及地形分异特征

林业资源管理 2022年第2期 91-99页

作者：高倩倩陈灿刘贺娜罗倩李霞林勇明吴承祯福建农林大学林学院武夷学院生态与资源工程学院福建林业职业技术学院福建农林大学福建省高校森林生态系统过程与经营重点实验室

为揭示区域地形复杂性对植被覆盖度的影响以及为流域地区制定合理的经济和环保策略提供依据，以福建省闽江流域为研究区，基于Landsat TM和Landsat OLI影像，利用混合像元分解法估算了闽江流域2003,2009,2014,2019年4个时期的植被覆盖... 详细信息

为揭示区域地形复杂性对植被覆盖度的影响以及为流域地区制定合理的经济和环保策略提供依据，以福建省闽江流域为研究区，基于Landsat TM和Landsat OLI影像，利用混合像元分解法估算了闽江流域2003,2009,2014,2019年4个时期的植被覆盖度，得到闽江流域植被覆盖度时空动态特征及植被变化地形分异特征。结果表明：1)闽江流域植被覆盖度从2003年的0.72增加到2019年的0.81,呈上升趋势，山地密集地区植被覆盖度情况优于河湖沿岸地区。2)流域整体向修复方向发展，植被覆盖度Ⅰ、Ⅱ、Ⅲ、Ⅳ等级向Ⅴ等级转变，除Ⅴ等级面积扩张外，各等级面积均呈现收缩现象，收缩面积为Ⅳ(0.43)>Ⅲ(0.39)>Ⅱ(0.36)>Ⅰ(0.17)。3)平地植被覆盖度值最小，随着海拔和坡度升高闽江流域植被覆盖度增加；海拔<377m、坡度<30°范围内，退化面积大于修复面积，平地植被覆盖度稳定性最低。通过分析可知，闽江流域植被覆盖度受地形因子的影响，制定植被修复政策时，需充分考虑地形因素。

关键词：闽江流域植被覆盖度时空变化地形

中低剪力下轴向力、弯矩和扭矩作用时钢筋混凝土圆柱的抗震性能

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钢结构(中英文) 2010年第1期 83-83页

作者： suriya Prakash Abdeldjelil Belarbi Young-Min You

对混凝土柱在循环受弯、剪、纯扭以及各种弯、剪、扭组合荷载下的试验结果进行介绍。研究中涉及的主要变量为扭矩弯矩比,柱的高径比或弯矩剪力比(中、低剪力模拟时)。高径比决定了弯矩-剪力交互作用的水平。在组合荷载下,对扭矩弯矩比为... 详细信息

对混凝土柱在循环受弯、剪、纯扭以及各种弯、剪、扭组合荷载下的试验结果进行介绍。研究中涉及的主要变量为扭矩弯矩比,柱的高径比或弯矩剪力比(中、低剪力模拟时)。高径比决定了弯矩-剪力交互作用的水平。在组合荷载下,对扭矩弯矩比为0·2和0·4,高径比为3和6的柱进行试验。分析了高径比提高对各种性能的影响。特别研究了组合荷载下剪力水平对破坏模式以及对弯剪强度的重要影响。试验结果表明:随着高径比的减少弯曲和扭转承载力与有限元计算结果没有显著变化;但是高径比的减少会导致破坏模式和变形性能的显著变化。

关键词：圆柱组合荷载约束延性有限元中低剪力荷载交互螺旋箍筋扭矩

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电力系统电源规划的数学模型及实现

现代电力 2000年第2期17卷 8-13页

作者：黄伟曲和南徐明荣于晗华北电力大学(北京)电力工程系北京102206

在电源电网一体优化模型中 ,将输电网络规划到 2 2 0 k v.压等级 ,电源和负荷点与实际地理位置相对应。该模型从经济角度将电源电网规划有机结合 ,用最小费用增益网络流算法优化电力网络 ,并利用系统装机容量逐台扩展的方式 ,克服了电... 详细信息

在电源电网一体优化模型中 ,将输电网络规划到 2 2 0 k v.压等级 ,电源和负荷点与实际地理位置相对应。该模型从经济角度将电源电网规划有机结合 ,用最小费用增益网络流算法优化电力网络 ,并利用系统装机容量逐台扩展的方式 ,克服了电源电网一体优化的计算复杂性。同时 ,考虑了输电线直流潮流约束。经实例演算。

关键词：电力系统电源规划数学模型最优规划

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Simulating Nitrogen and Irrigation Effects on Wheat Production in Bangladesh under Changing Climate

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American Journal of Plant Sciences 2017年第7期8卷 1593-1606页

作者： Ranjit Sen Apurba Kanti Choudhury Sohela Akhter Sheikh Ishtiaque Md. Abu hena Sorwar Jahan Faruque Ahmed Jatish Chandra Biswas Md. Maniruzzaman Md. Main Uddin Miah Md. Mizanur Rahman Nav.en Kalra Md. Abdul Aziz A. S. M. Mahbubur Rahman Khan Bangladesh Agricultural Research Institute Gazipur Bangladesh Bangladesh Rice Research Institute Gazipur Bangladesh Bangabandhu Sheikh Mujibur Rahman Agricultural Univ.rsity Gazipur Bangladesh CRP-II Project Krishi Gobeshona Foundation (KGF) Dhaka Bangladesh

Climate change impacts are v.sible in Bangladesh which requires adoption of judicious crop management practices for sustainable agriculture. Crop simulation models are effectiv. in this regard and can be used for optimizing water and nitrogen inputs for maximization of wheat yields. Two field studies were conducted at Bangladesh Agricultural Research Institute (BARI) for ev.luating the effect of increased temperature on wheat production under v.riable water and N rates, through the use of DSSAT v..6 model. Thirty years historic weather data and BARI Gom-26 wheat-cultiv.r coefficients, as generated through use of GLUE of DSSAT model, were used for ev.luating the impact of temperature rise with v.riable rates of irrigation water and nitrogen. The effects of four lev.ls of nitrogen (0, 40, 80 and 120 kg ha-1) and four irrigation lev.ls [0 (no irrigation), 1, 2 and 3] on wheat yield were ev.luated under 0°C, 1°C, 2°C and 3°C rise in temperature. Simulation results indicated that wheat yield increased with increase in nitrogen application rate, but decreased with the temperature rise. Crop growing duration was reduced by about fiv. days for each degree rise in temperature, irrespectiv. of lev.ls of irrigation water and nitrogen-rates. In general, there was yield reduction of 8.13, 16.77 and 24.97 % with increased temperature of 1°C, 2°C and 3°C, respectiv.ly, when compared with no temperature rise treatment. For interaction of temperature rise-N dose, the magnitude of yield decline under temperature rise was higher with increased dose of N. Agronomic N use efficiency at different N rates and temperature rise lev.l were calculated. N use efficiency decreases with the increase in temperature rise and the highest (29.95 kg grain kg-1 N) was obtained from 40 kg N ha-1 treated plot with 0°C temperature rise i.e. existing atmospheric temperature. Simulation results indicated increase in wheat yield with higher lev.ls of irrigation water, and int

关键词： Climate Change Wheat Temperature Rise Irrigation Nitrogen Bangladesh