检索结果-南通市图书馆

Belowground Tritrophic Food Chain Modulates soil Respiration in Grasslands

Pedosphere 2018年第1期28卷 114-123页

作者： andrey s.zaitsev Klaus BIRKHOFER Klemens EKsCHMITT Volkmar WOLTERs Institute of Animal Ecology Justus-Liebig-University of Giessen Department of Ecology Brandenburg University of Technology Cottbus-Senftenberg

Edaphic biota significantly affects several essential ecological functions such as C-storage, nutrient turnover, and ***, it is not completely understood how belowground animal contribution to these functions changes in grasslands subject to different land use types. A microcosm experiment was carried out to test the effect of a tritrophic food chain on CO_2 release from grassland soils. soil was collected from three differently managed grassland systems(meadow, pasture, and mown pasture) located in three distinct German regions that cover a north-south gradient of approximately 500 km. The tritrophic food chain comprised natural edaphic microflora, nematodes, and predatory gamasid mites. The experimental design involved a full factorial combination of the presence and absence of nematodes and gamasid mites. Nematodes significantly increased the CO_2 emissions in most treatments,but the extent of this effect varied with land use type. The fact that grazing by nematodes stimulated the metabolic activity of the edaphic microflora over a wide range of grassland soils highlighted the critical impact of the microfauna on ecosystem services associated with soil organic matter dynamics. Gamasids slightly amplified the effect of nematodes on microbial metabolic activity,but only in the pastures. This effect was most probably due to the control of nematode abundance. The fact that gamasid addition also augmented the impact of environmental conditions on nematode-induced modulation of soil respiration highlighted the need for including land use differences while evaluating soil fauna contribution to soil processes. To conclude, the differential response of the investigated tritrophic food chain to different grassland management systems suggests that adverse effects of land use intensification on important soil processes such as atmospheric C-release could potentially be reduced by using management methods that preserve essential features of the belowground fo

关键词： CO_2 emission land use microcosm nematodes predatory mites soil fauna soil food webs

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deep learning as a highly efficient tool for digital signal processing design

引用

Light(science & Applications) 2024年第11期13卷 2434-2435页

作者： andrey Pryamikov Prokhorov General Physics Institute of the Russian Academy of sciences MoscowRussia

The backpropagation algorithm,the most widely used algorithm for training artificial neural networks,can be effectively applied to the development of digital signal processing schemes in the optical fiber transmission *** signal processing as a deep learning framework can lead to a new highly efficient paradigm for cost-effective digital signal processing designes with low complexity.

关键词： signal digital fiber

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Control of light scattering by nanoparticles with optically-induced magnetic responses

引用

Chinese Physics B 2014年第4期23卷 41-51页

作者：刘伟 andrey E. Miroshnichenko Yuri s. Kivshar College of Optoelectronic science and Engineering National University of Defence Technology Nonlinear Physics Center and Center for Ultrahigh-bandwidth Devices for Optical systems CUDOs) Research School of Physics and EngineeringAustralian National University

Conventional approaches to control and shape the scattering pattems of light generated by different nanostructures are mostly based on engineering of their electric response due to the fact that most metallic nanostructures support only electric resonances in the optical frequency range. Recently, fuelled by the fast development in the fields of metamaterials and plasmonics, artificial optically-induced magnetic responses have been demonstrated for various nanostructures. This kind of response can be employed to provide an extra degree of freedom for the efficient control and shaping of the scattering patterns of nanoparticles and nanoantennas. Here we review the recent progress in this research direction of nanoparticle scattering shaping and control through the interference of both electric and optically-induced magnetic responses. We discuss the magnetic resonances supported by various structures in different spectral regimes, and then summarize the original results on the scattering shaping involving both electric and magnetic responses, based on the interference of both spectrally separated （with different resonant wavelengths） and overlapped dipoles （with the same resonant wavelength）, and also other higher-order modes. Finally, we discuss the scattering control utilizing Fano resonances associated with the magnetic responses.

关键词： optically-induced magnetic response scattering control Mie resonance Fano resonance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Merging bound states in the continuum in an open acoustic resonator

引用

science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li andrey E.Miroshnichenko school of Physics and Electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University school of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Gas-phase hydrogenation influence on defect behavior in titanium-based hydrogen-storage material

引用

Progress in Natural science:Materials International 2017年第1期27卷 105-111页

作者： Roman s.Laptev Viktor N.Kudiiarov Yuri s.Bordulev andrey A.Mikhaylov andrey M.Lider Department of General Physics Institute of Physics and Technology National Research Tomsk Polytechnic University

Titanium and its alloys are promising materials for hydrogen storage. However, hydrogen penetration accompanies the exploitation of hydrogen storage alloys. In particular, hydrogen penetration and accumulation in titanium alloys changes their mechanical properties. Therefore, the research works of such materials are mainly focused on improving the reversibility of hydrogen absorption-liberation processes, increasing the thermodynamic characteristics of the alloys, and augmenting their hydrogen storage capacity. In the process of hydrogenation-dehydrogenation, the formed defects both significantly reduce hydrogen storage capacity and can also be used to create effective traps for hydrogen. Therefore, the investigation of hydrogen interaction with structural defects in titanium and its alloys is very important. The present work, the hydrogen-induced formation of defects in the alloys of commercially pure titanium under temperature gas-phase hydrogenation（873 K） has studied by positron lifetime spectroscopy and Doppler broadening spectroscopy. Based on the evolution of positron annihilation parameters τ_f, τd, their corresponding intensities If, Idand relative changes of parameters s/s0and W/W0, the peculiarities of hydrogen interaction with titanium lattice defects were investigated in a wide range of hydrogen concentrations from 0.8at% to 32.0at%.

关键词： Titanium Hydrogen Lattice defects Positron annihilation Positron lifetime Doppler broadening

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Gas fiber lasers may represent a breakthrough in creating powerful radiation sources in the mid-IR

引用

Light(science & Applications) 2022年第2期11卷 153-155页

作者： andrey Pryamikov Prokhorov General Physics Institute of the Russian Academy of sciences 38 Vavilov streetMoscowRussia

Continuous wave fiber laser created on the basis of silica glass negative curvature hollow core fiber filled with HBr make it possible to obtain efficient narrow linewidth mid-IR emission with a maximum laser power of about 500mW at wavelength of 4200 *** is for the first time that emission from a continuous wave fiber laser have been achieved at a wavelength of 4496 nm with the largest tuning range of 686 nm.

关键词： fiber tuning breakthrough

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rising complexity of the OAM beam structure as a Way to a higher data capacity

引用

Light(science & Applications) 2022年第8期11卷 1648-1649页

作者： andrey Pryamikov Prokhorov General Physics Institute of the Russian Academy of sciences MoscowRussia

standard vortex beams carrying different OAM (optical angular momentum) modes can provide independent communication channels for information transmission. However, they are unable to reach the capacity limit of a communication channel due to a rapid divergence of the beams with high values of the OAM order. The solution can be found by using multi-vortex geometric beams.

关键词： OAM communication vortex

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

studies of ultrasonic dehydration efficiency

引用

Journal of Zhejiang University-science A(Applied Physics & Engineering) 2011年第4期12卷 247-254页

作者： Vladimir N. KHMELEV andrey V. sHALUNOV Roman V. BARsUKOV Denis s. ABRAMENKO andrey N. LEBEDEV Biysk Technological Institute (Branch) Altai state Technical University

The aim of this investigation was to define the effectiveness of non-contact drying using ultrasonic vibrations. Disk radiators were used for carrying out experiments, and a special drying chamber was designed to provide resonant amplification of ultrasonic vibrations (from 130 to 150 dB). Drying of ginseng and other vegetables demonstrated that the application of ultrasonic vibrations reduced power inputs by 20% in comparison with convective drying. It also led to a decrease of 6% in final moisture content, if the duration of drying was constant. The level of intensification of ultrasonic drying was high (up to 50 g for 1 kg of drying material), which helped to lower the temperature of the drying agent and improve the quality of the dried products.

关键词： Drying Ultrasound Vibration system Drying chamber Processing (treatment) of agricultural products

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhancing first-principles simulations of complex solid-state ion conductors using topological analysis of procrystal electron density

引用

npj Computational Materials 2022年第1期8卷 1777-1786页

作者： andrey Golov Javier Carrasco Centre for Cooperative Research on Alternative Energies(CIC energiGUNE) Basque Research and Technology Alliance(BRTA)01510Vitoria-GasteizSpain

Atomistic-level understanding of ion migration mechanisms holds the key to design high-performance solid-state ion conductors for a breadth of electrochemical ***-principles simulations play an important role in this ***,these methods are generally computationally-intensive,with limited access to complex,low-symmetry structures,such as *** we show how topological analysis of the procrystal electron density can be applied to efficiently mitigate this *** discuss how this methodology goes beyond current state of the art capabilities and demonstrate this with two *** the first,we examine Li-ion transport across grain boundaries in Li_(3)ClO ***,we compute diffusion coefficients as a function of charge carrier concentration in spinel LiTis_(2) electrode *** two case studies do not exhaust the opportunities and might constitute motivations for still more complex applied materials.

关键词： analysis state holds

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acoustic emission characterization of sliding wear under condition of direct and inverse transformations in lowtemperature degradation aged Y-TZP and Y-TZP-Al_2O_3

引用

Friction 2018年第3期6卷 323-340页

作者： Nikolai L sAVCHENKO andrey V FILIPPOV sergei Yu TARAsOV andrey I DMITRIEV Evgeny V sHILKO Aleksandr s GRIGORIEV Institute of strength Physics and Materials science sB RAs National Research Tomsk Polytechnic University National Research Tomsk state University

In this research, results of the investigation of the sliding friction and wear of yttria-stabilized tetragonal zirconia polycrystalline(Y-TZP) and Y-TZP-Al_2O_3 samples preliminarily subjected to low-temperature degradation are reported. The investigation was carried out using a pin-on-disk tribometer with simultaneous recording of acoustic emission(AE) and vibration acceleration. The sliding wear process was found to be determined by dynamic direct and inverse Y-TZP transformations detected by monoclinic and tetragonal X-ray diffraction peak ratios. The AE signals generated under direct and inverse transformations can be used to characterize wear and friction mechanisms as well as direct and inversed sliding-induced phase transformations. The AE signal energy grows with the friction coefficient and the inverse transformation degree. Reduction of the AE signal energy indicates establishing the mild wear stage caused by effective stress-induced direct martensitic transformation. The AE signal median frequency increases in the case of lower friction. Numerical studies of wear subsurface fracture under conditions of stress-induced martensitic transformation were used to elucidate the role played by the phase transformation in Y-TZP and Y-TZP-Al_2O_3. Martensitic transformation in Y-TZP was described with use of the non-associated dilatant plasticity model. simulation results particularly show that increase in the value of dilatancy coefficient from 0 to 0.2 is accompanied by 25%-30% reduce in characteristic length and penetration depth of sliding-induced subsurface cracks. As shown the AE may be an effective tool for in-situ monitoring the subsurface wear of materials experiencing both direct and inverse transformations.

关键词： zirconia transformation toughening low-temperature degradation friction acoustic emission numerical modeling movable cellular automata method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：