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Establishment of Numerical Wave Flume Based on the Second-Order Wave-Maker Theory

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China Ocean Engineering 2019年第2期33卷 160-171页

作者： ZHANG hao-chen LIU Shu-xue LI Jin-xuan WANG Lei State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

With growing computational power, the first-order wave-maker theory has become well established and is widely used for numerical wave flumes. However, existing numerical models based on the first-order wave-maker theory lose accuracy as nonlinear effects become prominent. Because spurious harmonic waves and primary waves have different propagation velocities, waves simulated by using the first-order wave-maker theory have an unstable wave profile. In this paper, a numerical wave flume with a piston-type wave-maker based on the second-order wave-maker theory has been established. Dynamic mesh technique was developed. The boundary treatment for irregular wave simulation was specially dealt with. Comparisons of the free-surface elevations using the first-order and second-order wave-maker theory prove that second-order wave-maker theory can generate stable wave profiles in both the spatial and time domains. Harmonic analysis and spectral analysis were used to prove the superiority of the second-order wave-maker theory from other two aspects. To simulate irregular waves, the numerical flume was improved to solve the problem of the water depth variation due to low-frequency motion of the wave board. In summary, the new numerical flume using the second-order wave-maker theory can guarantee the accuracy of waves by adding an extra motion of the wave board. The boundary treatment method can provide a reference for the improvement of nonlinear numerical flume.

关键词： second-order wave generation nonlinear wave spurious harmonic wave numerical flume

Creep behavior and permeability evolution of coal pillar dam for underground water reservoir

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International Journal of Coal Science & Technology 2023年第1期10卷 136-141页

作者： Yulong chen Xianjie hao Dongjie xue Zhe Li Xiaoran Ma State Key Laboratory of Water Resource Protection andUtilization in Coal Mining BeijingChina China University of Mining and Technology BeijingBeijingChina

Using goof as water storage space plays a vital role in the ecological environment and economic development of arid mining areas,while the rock strength and the stability of coal pillars in underground water reservoirs are closely related to creep *** this work,triaxial creep-seepage tests were conducted for coal samples to develop new insights into the creep behavior and permeability *** results showed that the creep deformation and permeability evolution of coal samples exhibit three stages,namely,the compaction hardening stage before the stress threshold,volumetric compaction stage,and volumetric dilatancy *** coal permeability decreases first and then increases with the creep strain and it is well correlated with the variation of volumetric strain.

关键词： Coal Creep Permeability Volumetric strain

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烯啶虫胺灌根对黄瓜安全性的研究

扬州大学学报（农业与生命科学版） 2012年第1期33卷 91-94页

作者：顾爱祥周福才齐晓花陈学好吴蔚任佳王萍陆莹莹扬州大学园艺与植物保护学院江苏扬州225009

为了探讨烯啶虫胺灌根法给药对黄瓜的安全性,在室内和大棚中对药后黄瓜的出苗率、苗期叶片、根、茎等生长情况进行研究。结果表明:当剂量为0.05、0.07 g·株-1时,烯啶虫胺灌根法对黄瓜的出苗、株高、茎秆增粗有一定的促进作用,但这种影... 详细信息

为了探讨烯啶虫胺灌根法给药对黄瓜的安全性,在室内和大棚中对药后黄瓜的出苗率、苗期叶片、根、茎等生长情况进行研究。结果表明:当剂量为0.05、0.07 g·株-1时,烯啶虫胺灌根法对黄瓜的出苗、株高、茎秆增粗有一定的促进作用,但这种影响随施用时间的推迟而逐渐减弱,直至消失。0.05 g·株-1剂量对黄瓜叶片和根的生长无明显影响,但较高剂量对叶片和根的生长有一定的抑制作用。因此,在正常的使用剂量下,烯啶虫胺灌根处理对于黄瓜生长是安全的。

关键词：黄瓜生长发育烯啶虫胺灌根

The dynamic development of bacterial community following long-term weathering of bauxite residue

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Journal of Environmental Sciences 2020年第4期32卷 321-330页

作者： hao Wu Li chen Feng Zhu William Hartley Yifan Zhang Shengguo xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Crop and Environment Sciences Department Harper Adams UniversityNewportShropshire TF108 NBUK

Bauxite residue is the industrial waste generated from alumina production and commonly deposited in *** sites are bare of vegetation due to the extreme high salinity and alkalinity,as well as lack of ***,long term weathering processes could improve residue properties to support the plant *** we investigate the development of bacterial communities and the geochemical drivers in bauxite residue,using Illumina high-throughput sequencing *** term weathering reduced the pH in bauxite residue and increased its nutrients *** bacterial community also significantly developed during long term weathering *** analysis revealed that natural weathering processes encouraged the populations of Proteobacteria,Chloroflexi,Acidobacteria and Planctomycetes,whereas reducing the populations of Firmicutes and *** analysis(RDA)indicated that total organic carbon(TOC)was the dominant factors affecting microbial *** results have demonstrated that natural weathering processes improved the soil development on the abandoned bauxite residue disposal areas,which also increased our understanding of the correlation between microbial variation and residue properties during natural weathering processes in Bauxite residue disposal areas.

关键词： Bauxite residue disposal areas Bacterial community Natural weathering processes Driving factors Soil formation

High-operating-temperature mid-infrared photodetectors via quantum dot gradient homojunction

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Light(Science & Applications) 2023年第3期12卷 355-365页

作者： Xiaomeng xue Menglu chen Yuning Luo Tianling Qin Xin Tang Qun hao School of Optics and Photonics Beijing Institute of TechnologyNo.5 Zhongguancun South StreetBeijingChina Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology BeijingChina Yangtze Delta Region Academy of Beijing Institute of Technology BeijingChina

Due to thermal carriers generated by a narrow mid-infrared energy gap,cooling is always necessary to achieve ideal *** quantum dot(QD),the electron thermal generation should be reduced with quantum confinement in all three *** a result,there would be a great potential to realize high-operating-temperature(HOT)QD mid-IR photodetectors,though not yet *** the advantages of colloidal nanocrystals’solution processability and precise doping control by surface dipoles,this work demonstrates a HOT mid-infrared photodetector with a QD gradient *** detector achieves background-limited performance with D^(*)=2.7×1011 Jones on 4.2μm at 80 K,above 10^(11) Jones until 200 K,above 10^(10 )Jones until 280 K,and 7.6×10^(9) Jones on 3.5μm at 300 *** external quantum efficiency also achieves more than 77%with responsivity 2.7 A/W at zero *** applications such as spectrometers,chemical sensors,and thermal cameras,are also approved,which motivate interest in low-cost,solution-processed and high-performance mid-infrared photodetection beyond epitaxial growth bulk photodetectors.

关键词： quantum gradient precise

外源褪黑素处理对采后水蜜桃冷藏品质及冷害发生的影响

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江苏农业学报 2020年第3期36卷 702-708页

作者：千春录朱芹高姗陈国华戚思影季正捷金昌海陈学好齐晓花扬州大学食品科学与工程学院江苏扬州225127 扬州大学园艺与植物保护学院江苏扬州225009

以琼花露水蜜桃为试验材料,研究不同浓度(50μmol/L、100μmol/L、150μmol/L、200μmol/L)褪黑素处理对桃果低温贮藏品质的影响。结果表明,100μmol/L褪黑素处理能有效抑制冷藏桃果硬度下降和失重率上升,从而保持冷藏桃果感官品质,减... 详细信息

以琼花露水蜜桃为试验材料,研究不同浓度(50μmol/L、100μmol/L、150μmol/L、200μmol/L)褪黑素处理对桃果低温贮藏品质的影响。结果表明,100μmol/L褪黑素处理能有效抑制冷藏桃果硬度下降和失重率上升,从而保持冷藏桃果感官品质,减轻冷害症状。褪黑素处理能有效抑制冷藏桃果相对电导率上升,丙二醛(MDA)积累,蛋白质和抗坏血酸降解,从而降低桃果氧化伤害。褪黑素处理能有效抑制多酚氧化酶(PPO)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)活性的上升,维持多酚含量,从而抑制果实褐变。总之,100μmol/L褪黑素处理通过抑制桃果褐变,降低氧化伤害,保持果实冷藏品质并抑制冷害发生。

关键词：水蜜桃褪黑素冷藏品质冷害褐变

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设施黄瓜烟粉虱的区域生态防控研究

环境昆虫学报 2017年第4期39卷 784-790页

作者：赵斌衡森陈学好苏宏华吴晓霞张海波周福才扬州大学园艺与植物保护学院兴化市农业技术推广中心农业部农产品质量安全生物性危害因子(动物源)控制重点实验室(26116120)

烟粉虱是设施蔬菜上的重要害虫。为探讨烟粉虱的可持续控制方法,在蔬菜试验基地,通过虫源清理、黄板诱杀、诱集剂诱杀和芹菜间作驱虫等综合措施,研究非化学措施对黄瓜烟粉虱的持续控制作用。结果表明:在烟粉虱扩散迁移阶段,虫源的距离... 详细信息

烟粉虱是设施蔬菜上的重要害虫。为探讨烟粉虱的可持续控制方法,在蔬菜试验基地,通过虫源清理、黄板诱杀、诱集剂诱杀和芹菜间作驱虫等综合措施,研究非化学措施对黄瓜烟粉虱的持续控制作用。结果表明:在烟粉虱扩散迁移阶段,虫源的距离与成虫向大棚的迁入量呈负相关,虫源虫量与迁入量呈正相关;虫源扰动对烟粉虱迁入具有促进作用;烟粉虱在扩散过程中对新寄主仍遵循就近选择的原则;对黄板的选择性明显高于黄瓜,两者之间的虫量比在7.91∶1~420.00∶1;在棚内使用黄板加引诱剂及黄板加芹菜对黄瓜上的烟粉虱均具有较好的控制作用,虫口减退率均达到90%以上。结果表明,区域生态防控是对烟粉虱进行可持续绿色控制的有效方式。

关键词：烟粉虱黄板诱集剂芹菜生态控制

Phase Separation of Polymer Blends Induced by an External Static Electric Field

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Chinese Journal of Polymer Science 2023年第6期41卷 972-980,I0011页

作者： Qian Zhang xue-hao He Department of Chemistry School of ScienceTianjin UniversityTianjin 300350China

The mechanism of the phase separation of polymer blends in the presence of a static electric field was investigated using the molecular dynamics with a modified coarse-grained polarizable *** electric field effects,i.e.,the promotion and hindrance of the phase separation,were found in the system of the upper critical solution temperature(UCST)by varying the dielectric properties of polymer *** simulation directly demonstrated that the electric field effects originate from the energy changes of intramolecular unit polarization,intermolecular van der Waals(VDW)and Coulomb interactions induced by the external electric *** relationship of the energy change and the dielectric constant for the system under electric field is *** interface orientation under electric field was found to happen even before the transition point of phase *** assuming that the relative order parameter of the phase separation undergoes the same fluctuations for a system with and without an electric field,the transition temperature under an electric field can be predicted,and quantitative consistency with simulations is obtained.

关键词： field. separation system

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网络空间安全态势感知研究

网络与信息安全学报 2016年第10期2卷 29-35页

作者：赵淦森吴杰超陈梓豪任雪琦谭昊翔马朝辉华南师范大学计算机学院广东广州510631 广东外语外贸大学思科信息学院广东广州510006

网络空间是继海、陆、空、太空后的第五大主权空间,其安全与国家安全紧密相关。如何在网络空间中及时发现安全威胁、防御攻击、溯源攻击等是当下面临的困境之一。对网络空间中多源、异构、割裂的资产,在构建可信IaaS的基础上,通过基于... 详细信息

网络空间是继海、陆、空、太空后的第五大主权空间,其安全与国家安全紧密相关。如何在网络空间中及时发现安全威胁、防御攻击、溯源攻击等是当下面临的困境之一。对网络空间中多源、异构、割裂的资产,在构建可信IaaS的基础上,通过基于本体论的键联数据语义网关联技术,构建网络空间安全态势感知模型,在保证融合数据访问控制安全的同时,对网络空间资产进行综合分析,以感知网络空间的安全态势,对网络空间治理具有一定的参考意义。

关键词：网络空间安全态势感知本体论语义网