检索结果-南通市图书馆

Artemia in the Salt Lakes of Russia:the Productivity of Populations,the Reserves of the Cysts and the Fisheries

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2014年第S1期88卷 87-88页

作者： Lyudmila LITVINENKO aleksandr LITVINENKO Elena BOYKO Kirill KUZANOV Federal State Unitary EnterpriseGosrybcenter State Agrarian University of Northern Urals

Artemia cysts are an extremely important component of aquaculture *** is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the die... 详细信息

关键词： Artemia salt lakes Russia productivity cysts

Description of Evaporation Curve by the Generalized Van-der-Waals-Berthelot Equation. Part I

在线全文

学校读者我要写书评

暂无评论

Journal of Physical Science and Application 2014年第8期4卷 524-530页

作者： aleksandr aleksandrovich Sobko A MProkhorov Academy of Engineering Sciences Moscow 123557 Russian Federation

The evaporation curve is calculated for the Van-der-Waals and Berthelot gases. It was shown that the evaporation curve of real gases resides between those of Van-der-Waals and Berthelot gases. The generalized Van-der-Waals-Berthelot equation is suggested, which not only qualitatively but also quantitatively describes evaporation curves of real gases. It was also shown that the generalized Van-der-Waals and Berthelot equation well describes other characteristics of real gases.

关键词： Van-der-Waals equation Berthelot equation generalized Van-der-Waals-Berthelot equation.

Negative thermal expansion in one-dimension of a new double sulfate AgHo(SO_(4))_(2)with isolated SO_4 tetrahedra

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第17期76卷 111-121页

作者： Yuriy G.Denisenko Victor V.Atuchin Maxim S.Molokeev Naizheng Wang Xingxing Jiang aleksandr S.aleksandrovsky Alexander S.Krylov aleksandr S.Oreshonkov Alexander E.Sedykh Svetlana S.Volkova Zheshuai Lin Oleg V.Andreev Klaus Müller-Buschbaum Institute of Chemistry Tyumen State University.Tyumen625003Russia Institute of Inorganic and Analytical Chemistry Justus-Liebig-University of Giessen35392Giessen.Germany Department of General and Special Chemistry Industrial University of TyumenTyumen625000Russia Laboratory of Optical Materials and Structures Institute of Semiconductor PhysicsSB RASNovosibirsk630090Russia Laboratory of Semiconductor and Dielectric Materials Novosibirsk State UniversityNovosibirsk630090Russia Research and Development Department.Kemerovo State University Kemerovo650000Russia Laboratory of Crystal Physics Kirensky Institute of PhysicsFederal Research Center KSC SB RASKrasnoyarsk660036Russia Siberian Federal University Krasnoyarsk660041Russia Department of Physics Far Eastern State Transport UniversityKhabarovsk680021Russia Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing100190China Laboratory of Coherent Optics Kirensky Institute of Physics.Federal Research Center KSC SB RASKrasnoyarsk660036Russia Institute of Nanotechnology Spectroscopy and Quantum ChemistrySiberian Federal UniversityKrasnoyarsk660041Russia Laboratory of Molecular Spectroscopy Kirensky Institute of PhysicsFederal Research Center KSC SB RASKrasnoyarsk660036Russia Center for Materials Research(LaMa) Justus-Liebig-University GiessenGiessen35392Germany University of the Chinese Academy of Sciences Beijing100049China Laboratory of the Chemistry of Rare Earth Compounds Institute of Solid State ChemistryUB RASEkaterinburg620137Russia

A double holmium-silver sulfate was obtained for the first *** temperature intervals for the formation and stability of the compound were determined by differential scanning *** crystal structure of AgHo(SO_(4))_(2)was determined by Rietveld *** X-ray diffraction(XRD)analysis showed that the compound crystallizes in the monoclinic syngony,space group P2_1/m,with the unit cell parameters a=4.71751(4)A,b=6.84940(6)A and c=9.89528(9)A,β=95.1466(4)·,V=318.448(5)A^(3),Z=2,R_B=1.55%,T=303 *** types of sulfate tetrahedra were found in the structure,which significantly affected the spectral properties in the infrared *** the temperature range of 143-703 K,a negative thermal expansion along the b direction accompanied by a positive thermal expansion along the a and c directions was *** was established that negative thermal expansion is the result of the deformation of sulfate tetrahedra,which is affected by the movement of holmium and silver *** excitation in the blue spectral range(457.9 nm)produces a luminescence in light blue(489 nm),green(545 nm)and red(654 nm)spectral ranges,and the latter two were of comparable intensity that is favorable for WLED *** observed luminescent band distribution is ascribed to the specific crystal field at Ho^(3+)ion sites rather than a variation of radiationless probability.

关键词： Sulfate Crystal structure Thermal expansion Raman Photoluminescence Band structure

Description of Evaporation Curve for Liquid Metals by the Generalized Van-der-Waals-Berthelot Equation. Part II

在线全文

学校读者我要写书评

暂无评论

Journal of Physical Science and Application 2017年第1期7卷 29-34页

作者： aleksandr aleksandrovich Sobko A M Prokhorov Academy of Engineering Sciences Moscow 12355 7 Russian Federation

In the present work it is shown that the generalized Van-der-Waals-Berthelot equation describes the evaporation curves （saturation curves） for alkali metals with good accuracy. This result is obtained on the basis of the calculations performed by the author for thermodynamic parameters of the saturation curves described by the generalized Van-der-Waals-Berthelot equation.

关键词： Van-der-Waals equation Berthelot equation generalized Van-der-Waals-Berthelot equation evaporation curve metals.

Device-based neuromodulation for cardiovascular diseases and patient’s age

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2022年第11期19卷 876-893页

作者： Evgeny N Mikhaylov Nigar Z Gasimova Natalia N Belyaeva Heber Ivan Condori Leandro aleksandr D Vakhrushev Evgeny V Shlyakhto Almazov National Medical Research Centre Saint-PetersburgRussia

The autonomic nervous system plays an important role in the pathogenesis of cardiovascular *** aging,autonomic activity changes,and this impacts the physiological reactions to internal and external *** sympathetic and parasympathetic responses seem to decline,reflecting functional and structural changes in nervous *** some investigators suggested that both the sympathetic and parasympathetic activities were suppressed,others found that only the parasympathetic activity was suppressed while the sympathetic activity *** addition,cardiac innervation progressively diminishes with ***,one may suggest that neuromodulation interventions may have different effects,and older age groups can express an attenuated *** article aims to discuss the effect of device-based neuromodulation in different cardiovascular diseases,depending on the patient’s ***,we cover renal denervation,pulmonary artery denervation,baroreceptor activation therapy,vagus nerve stimulation,spinal cord stimulation,ganglionated plexi ablation for the management of arterial and pulmonary hypertension,heart failure,angina and *** results of many clinical studies appeared to be *** view of the low rate of positive findings in clinical studies incorporating neuromodulation approaches,we suggest the underestimation of advanced age as a potential contributing factor to poorer *** of outcomes between different age groups in clinical trials may shed more light on the true effects of neuromodulation when neutral/ambiguous results are obtained.

关键词： stimulation cardiovascular diseases

Numerical Simulation for Investigation and Design of Steel Strip Induction Heating Lines for Rolling Mills

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2012年第S2期19卷 658-661页

作者： NIKANOROV aleksandr NACKE Bernard LEE Dukman YOU Jongwoo Institute of Electrotechnology Leibniz Universitt Hannover POSCO Technical Research Laboratories

Continuous steel strip casting lines in rolling miles are under active *** to high thermal losses the thin strip is cooling down very fast and therefore a sufficient heating system is necessary before final *** induction heaters can realize the necessary fast heating of the strip and a good energy efEciency of *** of induction heating lines for rolling mills are of extremely high power,all even small improvements in their design and operating modes have significant technical and economical ***,the heating lines need an optimal design of the complex induction systems and only numerical simulation is a way to solve the *** two- and threedimensional numerical simulation approaches developed and applied for investigation and design of longitudinal induction heaters are described in the *** numerical models have been successfully used for development of modified coils allowing high efficient heating of thinner strip using the same operating *** electrical impedance of the modified coils has been provided on the level necessary for using the existing power supplies and matching *** high electrical efficiency,the modified coils improve the temperature distribution over the strip width by increased heating of the strip *** optimized and modifies induction coils have been successfully tested in industrial line.

关键词： steel strip induction heating rolling mills numerical simulation

Strain-Rate Dependency of a Unidirectional Filament Wound Composite under Compression

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2023年第12期137卷 2149-2161页

作者： Stepan Konev Victor A.Eremeyev Hamid M.Sedighi Leonid Igumnov Anatoly Bragov aleksandr Konstantinov Ayaulym Kuanyshova Ivan Sergeichev Skolkovo Institute of Science and Technologies Center for Materials TechnologiesMoscowRussia National Research Lobachevsky State University of Nizhny Novgorod Nizhny NovgorodRussia Dipartimento di Ingegneria Civile Ambientale e Architettura(DICAAR)Universitàdegli Studi di CagliariCagliari(CA)Italy Mechanical Engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvazIran Drilling Center of Excellence and Research Center Shahid Chamran University of AhvazAhvazIran

This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under *** test samples were manufactured through the filament winding of flat *** establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure Bar method,and standard static *** samples were loaded both along and perpendicular to the direction of the reinforcing *** applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during *** a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were *** on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are *** is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under *** increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,*** loading resulted in a strength and elastic modulus increase by 58%and 50%,*** average strength along the fibers at the largest studied strain rate was about *** obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.

关键词： High strain rate composites filament winding dynamic strength Split Hopkinson Pressure Bar compression

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于改进粒子滤波的无人机编队协同导航算法

航空学报 2023年第14期44卷 246-257页

作者：岳敬轩王红茹朱东琴 aleksandr Chupalov 哈尔滨工程大学信息与通信工程学院哈尔滨150001

针对复杂环境下因外界干扰产生时变非高斯噪声的情况下主从式无人机群协同导航效果较差的问题,提出了一种改进的粒子滤波(PF)算法以提高导航精度,并降低了对从机测量设备的精度要求。首先以主机的高精度惯性导航系统(INS)和全球定位系统... 详细信息

针对复杂环境下因外界干扰产生时变非高斯噪声的情况下主从式无人机群协同导航效果较差的问题,提出了一种改进的粒子滤波(PF)算法以提高导航精度,并降低了对从机测量设备的精度要求。首先以主机的高精度惯性导航系统(INS)和全球定位系统(GPS)导航信息为基准,结合从机上的低精度传感器,建立了观测模型。其次,利用改进的PF算法实现了多源导航信息的融合。针对PF的重要性概率密度函数选取和粒子退化问题,在扩展粒子滤波(EPF)的基础上,引入Levenberg-Marquardt迭代方法,保证滤波的稳定性和收敛性。在重采样阶段采用快速重采样方法,将得到的粒子集进行分类,对中等权重粒子不再进行重采样,其余粒子在归一化过程中利用自适应权重因子优化,使获得的样本粒子权重更加均匀,从而提高了计算效率和导航实时性。将提出的方法与其他几种PF进行对比,仿真结果表明,该算法可以有效地提高无人机(UAV)编队协同导航精度,具有一定实用价值。

关键词：无人机编队协同导航扩展粒子滤波 Levenberg-Marquardt迭代重采样

Factorization of Functional Operators with Involutive Rotation on the Unit Circle

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics 2020年第11期11卷 1132-1138页

作者： aleksandr Karelin Anna Tarasenko Institute of Basic Sciences and Engineering Hidalgo State University Pachuca Mexico

Following the classical definition of factorization of matrix-functions, we introduce a definition of factorization for functional operators with involutive rotation on the unit circle. Partial indices are defined and their uniqueness is proven. In previous works, the main research method for the study scalar singular integral operators and Riemann boundary value problems with Carlemann shift were operator identities, which allowed to eliminate shift and to reduce scalar problems to matrix problems without shift. In this study, the operator identities were used for the opposite purpose: to transform operators of multiplication by matrix-functions into scalar operators with Carlemann linear-fractional shift.

关键词： Carlemann Shift Operator Identities Factorization Involutive Rotation