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Dependence of the E. coli promoter strength and physical parameters upon the nucleotide sequence 被引量:1
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作者 BEREZHNOY AndreyY. SHCKORBATOV Yuriy G. 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第11期1063-1068,共6页
The energy of interaction between complementary nucleotides in promoter sequences of E. coli was calculated and visualized. The graphic method for presentation of energy properties of promoter sequences was elaborated... The energy of interaction between complementary nucleotides in promoter sequences of E. coli was calculated and visualized. The graphic method for presentation of energy properties of promoter sequences was elaborated on. Data obtained indicated that energy distribution through the length of promoter sequence results in picture with minima at –35, –8 and +7 regions corresponding to areas with elevated AT (adenine-thymine) content. The most important difference from the random sequences area is related to –8. Four promoter groups and their energy properties were revealed. The promoters with minimal and maximal energy of interaction between complementary nucleotides have low strengths, the strongest promoters correspond to promoter clusters characterized by intermediate energy values. 展开更多
关键词 核苷序列 DNA 脱氧核糖核酸 分子结构 随机序列
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Measurement of neutron and charged particle fluxes toward earthquake prediction 被引量:1
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作者 Asatulla U.Maksudov Mars A.Zufarov 《Earthquake Science》 CSCD 2017年第5期283-288,共6页
In this paper, we describe a possible method for predicting the earthquakes, which is based on simultaneous recording of the intensity of fluxes of neutrons and charged particles by detectors, commonly used in nuclear... In this paper, we describe a possible method for predicting the earthquakes, which is based on simultaneous recording of the intensity of fluxes of neutrons and charged particles by detectors, commonly used in nuclear physics. These low-energy particles originate from radioactive nuclear processes in the Earth's crust. The variations in the particle flux intensity can be the precursor of the earth- quake. A description is given of an electronic installation that records the fluxes of charged particles in the radial direction, which are a possible response to the accumulated tectonic stresses in the Earth's crust. The obtained results showed an increase in the intensity of the fluxes for 10 or more hours before the occurrence of the earthquake. The previous version of the installation was able to indicate for the possibility of an earthquake (Maksudov et al. in Instrum Exp Tech 58:130-131, 2015), but did not give information about the direction of the epicenter location. In this regard, the installation was modified by adding eight directional detectors. With the upgraded setup, we have received both the predictive signals, and signals determining the directions of the location of the forthcoming earthquake, starting 2-3 days before its origin. 展开更多
关键词 DETECTOR Neutron flux·Charged particles ·Radioactive decay EARTHQUAKE
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Theoretical and experimental study of 3-D initial fracture and its significance to faulting 被引量:1
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作者 Shiyu Li Taiming He +2 位作者 Chunkai Teng Xuyao Zheng Kuksenko Viktor 《Earthquake Science》 CSCD 2011年第3期283-298,共16页
The experimental results of 3-D fracture under compression are introduced in brief and the theory of stress criterion of 3-D fracture is studied. Methods to imitate initial fractures are developed. It is pointed that ... The experimental results of 3-D fracture under compression are introduced in brief and the theory of stress criterion of 3-D fracture is studied. Methods to imitate initial fractures are developed. It is pointed that there are important defects in the extreme value (EV) method ever proposed by Palaniswamy and Knauss. The major defect lies in that only two Euler angles (2EA) are considered, but another one is neglected. If the variation of all the three Euler angles (3EA) are considered, one can get better result which is consistent with the observation of faulting that extends on curved surfaces but not on planes. The method of evaluating maximal normal stress direction vector (NSDV) is proposed and further proved to be equivalent to the 3EA method. It is proved that the NSDV method can be further optimized to the method of composition of the first principal differential plane (CFPDP). The results from CFPDP method can fit the curved surfaces of initial growth observed in the experiments of 3-D fracture. The CFPDP method can also be used to interpret the 3-D fractures of the slipping section between the asperities in the buried fault plane that is modeled as ellipse crack. The results of 3-D fracture can be applied to interpreting the related problems of faulting including the mechanism of a lot of shatter rocks with different dimensions, the cause of earthquakes occurred at the edge of plate under low shear stress, and the mechanism of anisotropy caused by the extensive dilatancy anisotropy (EDA) cracks. 展开更多
关键词 fracture mechanics 3-D fracture FAULT fracture criterion
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Membrane Separator Interface for Mass-Spectrometric Analysis of Desflurane, Propofol and Fentanyl in Plasma and Cerebrospinal Fluid 被引量:1
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作者 V. Yu. Cherebillo V. N. Sokolov +3 位作者 V. A. Elokhin V. I. Nikolaev A. V. Polegaev A. Yu. Elizarov 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2015年第4期263-267,共5页
Mass-spectrometric interface for the measurement of anaesthetic agent concentration in biological fluids (blood plasma and cerebrospinal fluid) is described. Sampling of biological fluids was performed during balanced... Mass-spectrometric interface for the measurement of anaesthetic agent concentration in biological fluids (blood plasma and cerebrospinal fluid) is described. Sampling of biological fluids was performed during balanced inhalational (desflurane, fentanyl) anaesthesia and total intravenous (propofol, fentanyl) anaesthesia. The described method for drug concentration measurement in biologic fluids does not require long-term sample processing before injecting the sample into mass-spectrometer interface, in contrast to chromatographic methods. A hydrophobic membrane was used in the interface to separate anaesthetic agents from biological fluids: inhalational anaesthetic desflurane, hypnotic propofol, analgesic fentanyl. A possibility to use the interface for measurement of desflurane and propofol absolute concentration in blood plasma and cerebrospinal fluid was demonstrated for the study of blood-brain barrier (BBB) properties. 展开更多
关键词 MEMBRANE MASS-SPECTROMETER ANESTHESIA DESFLURANE FENTANYL
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Main Characteristics of Dust Storms and Their Radiative Impacts: With a Focus on Tajikistan 被引量:1
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作者 Sabur.F.Abdullaev Irina.N.Sokolik 《Journal of Atmospheric Science Research》 2019年第2期1-21,共21页
known aridity of the region is a major factor in promoting numerous dust storms. They have many diverse impacts on the environment and the climate of the region. The classification of dust storms and synoptic conditio... known aridity of the region is a major factor in promoting numerous dust storms. They have many diverse impacts on the environment and the climate of the region. The classification of dust storms and synoptic conditions related to their formation in Central Asia are discussed in the content of their diverse impact. We address dust optical properties that are representative of the region. Dust storms significantly reduce visibly and pose a human health threads. They also cause a significant impact on the radiative regime. As a result, dust storms may cause a decrease in temperature during daytime of up to 16℃ and an increase in temperature during night time from up to 7℃ compared to a clear day. 展开更多
关键词 DUST storms DUST HAZE Temperature effect of AEROSOL AEROSOL optical thickness Desert ZONE ARID ZONE DUST AEROSOL
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Regularities in the E. coli promoters composition in connection with the DNA strands interaction and promoter activity
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作者 BEREZHNOY Andrey Yu SHCKORBATOV Yuriy G. HISANORI Kiryu 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第12期969-973,共5页
The energy of interaction between DNA strands in promoters is of great functional importance. Visualization of the energy of DNA strands distribution in promoter sequences was achieved. The separation of promoters in ... The energy of interaction between DNA strands in promoters is of great functional importance. Visualization of the energy of DNA strands distribution in promoter sequences was achieved. The separation of promoters in groups by their energetic properties enables evaluation of the dependence of promoter strength on the energetic properties. The analysis of groups (clusters) of promoters distributed by the energy of DNA strands interaction in ?55, ?35, ?10 and +6 sequences indicates their connection with the transcriptional activity. 展开更多
关键词 DNA序列 启动强度 DNA链交互能量 DNA序列分类
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用NMR研究洋葱碳吸附水后的抗磁性(英文)
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作者 A M Panich V Yu Osipov2 K Takai 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2014年第5期392-397,共6页
对洋葱状碳缺陷位吸附水分子的1H化学位移进行测试,并比较块状水和石墨烯、氧化石墨烯和纳米金刚石吸附水的化学位移。纳米金刚石和氧化石墨烯绝缘体的1H共振位置与块状水接近,然而石墨烯和洋葱碳吸附水呈现明显的化学位偏移,这是由导... 对洋葱状碳缺陷位吸附水分子的1H化学位移进行测试,并比较块状水和石墨烯、氧化石墨烯和纳米金刚石吸附水的化学位移。纳米金刚石和氧化石墨烯绝缘体的1H共振位置与块状水接近,然而石墨烯和洋葱碳吸附水呈现明显的化学位偏移,这是由导电的石墨烯片层抗磁屏蔽效应所致。质子的化学位移和抗磁性之间存在显著的相关性。 展开更多
关键词 洋葱碳 石墨烯 反磁性 核磁共振
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Self-organization of Atoms into Nanosystems
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作者 Titorov Dmitriy 《Journal of Chemistry and Chemical Engineering》 2012年第9期809-813,共5页
关键词 原子间 自组织 纳米系统 泡利不相容原理 几何模型 应用程序 电子结构 距离计算
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The Classical Simulation of Interatomic Bonds on the Grain Boundaries and Joints
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作者 Titorov Dmitriy Borisovich 《材料科学与工程(中英文A版)》 2011年第6期833-837,共5页
关键词 原子间 债券 接头 晶界 模拟 古典 晶粒边界 原子模型
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Spatial Electronic Structures and Different Magnitude of Electroconductivity
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作者 Titorov Dmitriy Borisovich 《材料科学与工程(中英文B版)》 2012年第10期575-581,共7页
关键词 电子结构 导电性 空间 电子密度 不均匀 电子层 凝聚态 决定性
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Isolated Cobalt Nanoparticles Prepared on HOPG in Ultrahigh Vacuum Using Thermal Annealing
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作者 Denis Lebedev Niyaz Nurgazizov +1 位作者 Anton Chuklanov Anastas Bukharaev 《Advances in Nanoparticles》 2013年第3期236-240,共5页
Cobalt nanoparticles on the surface of highly oriented pyrolytic graphite have been studied by atomic force microscopy. Thermal annealing in ultrahigh vacuum was used to change the size of cobalt nanoparticles and the... Cobalt nanoparticles on the surface of highly oriented pyrolytic graphite have been studied by atomic force microscopy. Thermal annealing in ultrahigh vacuum was used to change the size of cobalt nanoparticles and their surface distribution. The effect of two key parameters, annealing time and temperature, on the size and the surface distribution of nanoparticles has been studied. The dependence of the particle size on these parameters has been obtained. It has been shown that the main mechanism of the nanoparticle growth is Ostwald ripening. 展开更多
关键词 NANOPARTICLES Thermal ANNEALING Ultrahigh VACUUM HOPG
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Thermophoresis of Carboxylic Nanotubes in Gaseous Atmosphere
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作者 Aleksey Bubenchikov Aleksandr Potekaev +2 位作者 Mikhail Bubenchikov Vladimir Korobitsyn Ivan Klykov 《Advances in Nanoparticles》 2014年第1期36-40,共5页
The present paper deals with motion of carbon nanotubes in a temperature gradient field. A determined-static theory of nanosized particles’ thermophores is developed. Analytical expressions for thermophoretic velocit... The present paper deals with motion of carbon nanotubes in a temperature gradient field. A determined-static theory of nanosized particles’ thermophores is developed. Analytical expressions for thermophoretic velocity and force of ultramicroheterogeneous particles in a gaseous atmosphere under near-normal conditions are provided. The calculations performed according to the suggested theory, as applied to closed carbon nanotubes, found the value of dimensionless velocity of thermophoresis. In accordance with the proposed hypothesis, Waldman’s limit is achieved, which is expressed in constancy of thermophoretic velocity within the interval of the Knudsen parameter change from 10 to 100. In addition, it is found out that under conditions defined below, velocity of thermophoresis is independent of the length of a carboxylic nanotube. A good agreement with experiments is reached, which makes it possible to assume correspondence of the theory to the physical truth. 展开更多
关键词 THERMOPHORESIS Carboxylic Tube Dynamics of Nanoparticles IDEAL Gas Statistical Distribution Monokinetic Model MATHEMATICAL Modelling
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The descent of pieces of the Tunguska cosmic body
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作者 Olga G. Gladysheva 《Natural Science》 2013年第5期563-566,共4页
There is a hypothesis that fragments of a body from outer space fell to Earth as a result of the Tunguska event. During decades of investigations at the site of the disaster, stone or iron pieces from a cosmic body we... There is a hypothesis that fragments of a body from outer space fell to Earth as a result of the Tunguska event. During decades of investigations at the site of the disaster, stone or iron pieces from a cosmic body were not found. In spite of this, the number of adherents of this hypothesis is growing. For one thing, it was determined that the formation of swamp craters at the epicentre of the disaster is contempory with the Tunguska event. Secondly, it was proven that the swamp craters are the result of thermokarst processes: their formation is connected with heat exchange in a permafrost zone. Now we can affirm that fragments of the Tunguska cosmic body (as a comet) with a mass of 10-3 ≤ M ≤ 10 kg reached the Earth’s surface, but they did not form craters. This conclusion was made from the isotopes and composition of element in peat deposits as determined by Kolesnikov’s group and L’vov. 展开更多
关键词 Tunguska COSMIC BODY CRATERS ORGANIC COMPONENT
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Space-Time Properties as Quantum Effects. Restrictions Imposed by Grothendieck’s Scheme Theory
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作者 Leonid Lutsev 《Journal of Modern Physics》 2019年第7期795-823,共29页
In this paper we consider properties of the four-dimensional space-time manifold M caused by the proposition that, according to the scheme theory, the manifold M is locally isomorphic to the spectrum of the algebra A,... In this paper we consider properties of the four-dimensional space-time manifold M caused by the proposition that, according to the scheme theory, the manifold M is locally isomorphic to the spectrum of the algebra A, M &cong;Spec (A), where A is the commutative algebra of distributions of quantum-field densities. Points of the manifold M are defined as maximal ideals of density distributions. In order to determine the algebra A, it is necessary to define multiplication on densities and to eliminate those densities, which cannot be multiplied. This leads to essential restrictions imposed on densities and on space-time properties. It is found that the only possible case, when the commutative algebra A exists, is the case, when the quantum fields are in the space-time manifold M with the structure group SO (3, 1) (Lorentz group). The algebra A consists of distributions of densities with singularities in the closed future light cone subset. On account of the local isomorphism M &cong;Spec (A) , the quantum fields exist only in the space-time manifold with the one-dimensional arrow of time. In the fermion sector the restrictions caused by the possibility to define the multiplication on the densities of spinor fields can explain the chirality violation. It is found that for bosons in the Higgs sector the charge conjugation symmetry violation on the densities of states can be observed. This symmetry violation can explain the matter-antimatter imbalance. It is found that in theoretical models with non-abelian gauge fields instanton distributions are impossible and tunneling effects between different topological vacua | n> do not occur. Diagram expansion with respect to the -algebra variables is considered. 展开更多
关键词 SPACE-TIME PROPERTIES Quantum Field ARROW of Time CHIRALITY ALGEBRA of Distributions Symmetry VIOLATION
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A New Paradigm for Metallic Alloys in Materials Science
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作者 Y. Ustinovshikov 《Advances in Materials Physics and Chemistry》 2015年第7期244-270,共27页
In the article, taking into account the phase transition “ordering-phase separation” discovered in alloys, new concepts about the diffusion phase transformations in alloys are formulated: chemical interaction betwee... In the article, taking into account the phase transition “ordering-phase separation” discovered in alloys, new concepts about the diffusion phase transformations in alloys are formulated: chemical interaction between dissimilar atoms exists always in all alloys and at any temperature of heating;alloys offer a surprising and not previously known property of changing the sign of the chemical interaction between dissimilar atoms at a change of the temperature or composition of alloys;diffusion processes occurring in alloys at different temperatures depend on the sign and the absolute magnitude of the energy of the chemical interaction between dissimilar atoms. All these three concepts are analyzed in detail, by the example of Ni-based and Co-based binary alloys using experimental results obtained by transmission electron microscopy. It is shown, on these ideas, how to carry out heat treatment of alloys more rationally, what principles should underpinned in the base of the construction of phase diagrams, how the microstructures of ordering and phase separation affect some properties of alloys. 展开更多
关键词 PHASE TRANSITIONS Transmission Electron MICROSCOPY Microstructure PHASE DIAGRAMS
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The Research of Fractal Characteristics of the Electrocardiogram in a Real Time Mode
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作者 Valery Antonov Anatoly Kovalenko +1 位作者 Artem Zagaynov Vu Van Quang 《Journal of Mathematics and System Science》 2012年第3期191-195,共5页
关键词 动态心电图 分形特征 现代时间序列分析方法 非线性分析方法 实时 调查结果 心电监护 混沌理论
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Deformation characteristics and inertial effect of complex aluminum alloy sheet part under impact hydroforming:experiments and numerical analysis
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作者 Liang-Liang Xia Shi-Hong Zhang +3 位作者 Yong Xu Shuai-Feng Chen Boris B.Khina Artur I.Pokrovsky 《Advances in Manufacturing》 SCIE EI CAS CSCD 2023年第2期311-328,共18页
Impact hydroforming(IHF),as a novel sheet metal forming technology with the advantages of high strain rate forming and flexible liquid loading,is highly suitable for efficiently manufacturing aluminum complex-shaped s... Impact hydroforming(IHF),as a novel sheet metal forming technology with the advantages of high strain rate forming and flexible liquid loading,is highly suitable for efficiently manufacturing aluminum complex-shaped sheet parts.In this paper,deformation characteristics of complex sheet parts under IHF are systematically investigated.The mechanical properties of 2024 aluminum alloy under a wide range of strain rates(10-3 s-1–3.3×103 s-1)were studied.It indicated that the elongation of 2024 aluminum alloy was improved by 116.01%under strain rates of 3.306-×-103 s-1,referring to 10-3 s-1.Further,a complex-shaped part with symmetrical and asymmetrical structures was selected.The deformation characteristics of sheet and role of inertial effect under IHF were investigated with well-developed solid–liquid coupling finite element(SLC-FE)model with high accuracy.Differentiating deformation tendency is found for symmetrical structure with notably prior deformation at central zone,showing a“bulging”profile at initial forming stage.Whereas,synchronous deformation is presented for asymmetrical structure with a“flat”profile.Additionally,distinctive inertial effect was observed at different positions change for both symmetrical and asymmetrical structures,in which lower values were resulted at their central regions.Meanwhile,the inertial effect evolved with the impacting speed.Specially,larger difference of inertial effect was observed with increasing impacting speed. 展开更多
关键词 2024 aluminum alloy Impact hydroforming High strain rate Inertial effect
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The development of semiconductor detectors for radiometers of alpha‑radiation and the examination of the volumetric activity of radon in various areas
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作者 B.S.Radzhapov S.A.Radzhapov +1 位作者 F.G.Mullagalieva M.A.Zufarov 《Radiation Detection Technology and Methods》 CSCD 2023年第3期457-463,共7页
Purpose Development of highly sensitive semiconductor detectors of large diameter and manufacturing of a measuring complex—a radiometer based on the developed detectors for studying the activity of alpha particles an... Purpose Development of highly sensitive semiconductor detectors of large diameter and manufacturing of a measuring complex—a radiometer based on the developed detectors for studying the activity of alpha particles and the volumetric activity of radon in various media.Methods The detectors were manufactured using surface-barrier and heterojunction technologies.Polishing etchant formulations for silicon have been developed.To obtain plane-parallelism of the plates during chemical etching,a special dynamic setup was used.The structure of the radiometer,electrical circuits,and device software have been developed.Results The results of the development of technology for the manufacture of detectors of large dimensions(30-100 mm in diameter)are presented.Studies of the electrical and radiometric characteristics of surface-barrier n detectors and detectors based on Al-αGe-pSi-Au heterojunctions were carried out.The principle of operation of the electronic components of a radiometer made using these detectors is also given.Conclusion The data of monitoring of radon content in soil air are given.Monitoring results showed that the concentration varies depending on temperature,humidity,and time of day.The GSM/SMS module allows the device to operate in real time. 展开更多
关键词 Silicon Semiconductor detectors RADIOMETER Alpha-radiation HETEROJUNCTION
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Influence of Features of Interphase Boundaries on Mechanical Properties and Fracture Pattern in Metal-Ceramic Composites 被引量:1
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作者 Sergey Psakhie Vladimir Ovcharenko +5 位作者 Baohai Yu Evgeny Shilko Sergey Astafurov Yury Ivanov Alexey Byeli Alexey Mokhovikov 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2013年第11期1025-1034,共10页
The results of a theoretical study on the influence of strength of interphase boundaries in metal-ceramic composite on macroscopical characteristics of composite response such as strength, deformation capacity, fractu... The results of a theoretical study on the influence of strength of interphase boundaries in metal-ceramic composite on macroscopical characteristics of composite response such as strength, deformation capacity, fracture energy and fracture pattern are presented. The study was conducted by means of computer-aided simulation by means of movable cellular automaton method taking account of a developed "mesoscopical" structural model of particle-reinforced composite. The strength of interphase boundaries is found to be a key structural factor determining not only the strength properties of metal-ceramic composite, but also the pattern and rate of fracture. The principles for achievement of the high-strength values of particle/binder interfaces in the metal-ceramic composition due to the formation of the wide transition zones (areas of variable chemical composition) at the interphase boundaries are discussed. Simulation results confirm that such transition zones provide a change in fracture mechanism and make the achievement of a high-strength and a high deformation capacity of metal-ceramic composite possible. 展开更多
关键词 Metal--ceramic composites Particle-reinforced composite Interphase boundaries Discrete element based analysis Strength and fracture energy Fracture pattern
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Doped GaSe crystals for laser frequency conversion 被引量:2
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作者 Jin Guo Ji-Jiang Xie +8 位作者 Dian-Jun Li Gui-Long Yang Fei Chen Chun-Rui Wang Lai-Ming Zhang Yury M Andreev Konstantin A Kokh Gregory V Lanskii Valery A Svetlichnyi 《Light(Science & Applications)》 SCIE EI CAS CSCD 2015年第1期47-58,共12页
In this review,we introduce the current state of the art of the growth technology of pure,lightly doped,and heavily doped(solid solution)nonlinear gallium selenide(GaSe)crystals that are able to generate broadband emi... In this review,we introduce the current state of the art of the growth technology of pure,lightly doped,and heavily doped(solid solution)nonlinear gallium selenide(GaSe)crystals that are able to generate broadband emission from the near infrared(IR)(0.8 mm)through the mid-and far-IR(terahertz(THz))ranges and further into the millimeter wave(5.64 mm)range.For the first time,we show that appropriate doping is an efficient method controlling a range of the physical properties of GaSe crystals that are responsible for frequency conversion efficiency and exploitation parameters.After appropriate doping,uniform crystals grown by a modified technology with heat field rotation possess up to 3 times lower absorption coefficient in the main transparency window and THz range.Moreover,doping provides the following benefits:raises by up to 5 times the optical damage threshold;almost eliminates two-photon absorption;allows for dispersion control in the THz range independent of the mid-IR dispersion;and enables crystal processing in arbitrary directions due to the strengthened lattice.Finally,doped GaSe demonstrated better usefulness for processing compared with GaSe grown by the conventional technology and up to 15 times higher frequency conversion efficiency. 展开更多
关键词 frequency conversion GASE solid solution crystal THZ
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