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Магніторезонансні та трибологічні властивості органопластів на основі співполімеру БСП-7 基于 BSP-7 共聚物的有机塑料的磁共振和摩擦学特性
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-20 DOI: 10.15407/ujpe68.9.619
M.O. Graschenkova, A.-M.V. Tomina, O.I. Burya, S.V. Krasnovyd, A.A. Konchyts’, B.D. Shanina
Методом електронного парамагнiтного резонансу дослiджено властивостi спiвполiмеру БСП-7, високомiцних i високомодульних кевлароподiбних органiчних волокон (ОВ) терлону та внiївлону в ролi наповнювачiв, а також компози-тiв БСП-7/ОВ. Встановлено наявнiсть та визначено властивостi дефектiв рiзного типу i магнiтних домiшок у вихiдних матерiалах та виготовлених композитах. Виявлено вплив взаємодiї матрицi з наповнювачами та оточуючим середовищем. У терлонi зареєстровано значну концентрацiю азотовмiсних радикалiв, пов’язаних iз наявнiстю мономерiв дiамiнiв у його структурi, що може негативно впливати на фiзико-механiчнi характеристики композитiв. З урахуванням отриманих даних розроблено ефективнi органопластики БСП-7/ОВ. Вимiрювання їх трибологiчних властивостей показали, що додавання оптимальної концентрацiї ОВ до полiмерної матрицi БСП-7 сприяє значному змен-шенню коефiцiєнта тертя, iнтенсивностi лiнiйного зношування та тепловидiлення. Кращi результати показали композити з терлоном, що пояснюється не тiльки його бiльш високим модулем пружностi, а i високим ступенем кристалiчностi структури, на вiдмiну вiд внiївлону з його майже аморфною гетероциклiчною структурою. Крiм того, процес синтезу композитiв передбачає застосування достатньо високих температур i тиску, в результатi чого азотнi радикали терлону руйнуються, i їхнiй негативний вплив на довготермiнову стабiльнiсть характеристик композита нiвелюється.
通过电子顺磁共振法研究了 BSP-7 共聚物、作为填充物的高强度和高模量凯夫拉类有机纤维(OMF)特隆和乙烯基伏龙以及 BSP-7/OMF 复合材料的特性。确定了起始材料和制造的复合材料中各种类型的缺陷和磁性杂质的存在及其性质。研究揭示了基体与填料和环境相互作用的影响。在 terlone 中发现了大量与二胺单体结构有关的含氮自由基,这会对复合材料的物理和机械特性产生不利影响。根据所获得的数据,开发出了有效的 BSP-7/OV 有机塑料。对其摩擦学特性的测量表明,在 BSP-7 聚合物基体中添加最佳浓度的 OM 有助于显著降低摩擦系数、线性磨损强度和发热量。使用特龙的复合材料显示出最佳效果,这不仅是因为其弹性模量较高,还因为其结构具有较高的结晶度,而不像乙烯具有几乎无定形的杂环结构。此外,在复合材料合成过程中需要使用足够高的温度和压力,从而破坏萜烯氮自由基,消除其对复合材料特性长期稳定性的负面影响。
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引用次数: 0
Monitoring of the Enzymatic Reactions Course by Differential Microwave Dielectrometry Method in Real Time 差分微波介电法实时监测酶促反应过程
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-20 DOI: 10.15407/ujpe68.9.608
K.S. Kuznetsova, V.A. Pashynska, Z.E. Eremenko, O.I. Shubnyi, A.V. Martynov, A.A. Prokopenko
Enzymatic reactions are the basis of many biotechnological manufacturing and biomedical diagnostic procedures that require effective methods of monitoring over the reaction course. In the current paper, we present the results of the development of a new approach within the differential microwave dielectrometry method for the non-invasive monitoring of the course of enzymatic reactions based on the complex permittivity changes of these reactive mixture solutions in real time at a fixed frequency of 31.82 GHz. The dynamic studies of the dielectric parameters of selected enzymatic systems containing a protein substrate (immunoglobulin G, human serum albumin) and enzyme trypsin. The developed differential microwave dielectrometry setup has been performed to verify the proposed approach effectiveness for the enzymatic reaction monitoring in biomedical practice and the food industry. Our microwave dielectrometry results have been validated by the results of the UV-Vis spectrophotometry method for selected enzymatic systems. We propose a new approach to use the differential microwave dielectrometry method with high sensitivity (in average 0.5% and 3÷5% for the real and imaginary parts of the complex permittivity, respectively) to estimate the course of enzymatic reactions in real time.
酶促反应是许多生物技术制造和生物医学诊断程序的基础,需要对反应过程进行有效监测的方法。在本文中,我们提出了一种基于这些反应混合溶液在31.82 GHz固定频率下的复介电常数变化的实时无创监测酶促反应过程的差分微波介电法新方法的发展结果。含有蛋白质底物(免疫球蛋白G,人血清白蛋白)和胰蛋白酶的选定酶系统的介电参数的动态研究。开发的差分微波介电测量装置已被执行,以验证所提出的方法在生物医学实践和食品工业中酶促反应监测的有效性。我们的微波介电测量结果已通过紫外可见分光光度法对所选酶体系的结果进行了验证。我们提出了一种新的方法,利用高灵敏度的差分微波介电法(复介电常数的实部和虚部平均分别为0.5%和3÷5%)实时估计酶促反应的过程。
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引用次数: 0
Synthesis and Characterization of a Novel Nanocomposite Polymer 一种新型纳米复合聚合物的合成与表征
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-20 DOI: 10.15407/ujpe68.9.638
A.S. Al-Kabbi, S.J. Abbas
One-dimensional nanostructures of PANI: PVA-g-EI nanocomposite are prepared by the interfacial polymerization method. The properties of a resulting green powder are studied by the X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), and infrared spectroscopy (FTIR). Prepared thin films were characterized by UV-Vis and photoluminescence (PL) spectroscopies. The XRD pattern of the nanocomposite shows that the higher volume fraction of crystalline phases corresponds to the PANI polymer with the accepted monoclinic unit cell of PVA. Nano-sized irregular particles arranged in clusters appear in the TEM measurements and SEM images, which testifies to the agglomeration without uniform packing. EDX confirms that the PVA-g-EI is incorporated in the structure of the polymer nanocomposite. A significant shift in the absorption edge with three PL independent emission peaks again confirms that PANI/PVA-g-EI form a nanocomposite.
采用界面聚合法制备了聚苯胺:PVA-g-EI纳米复合材料的一维纳米结构。通过x射线衍射(XRD)、能量色散x射线分析(EDX)、透射电子显微镜(TEM)和红外光谱(FTIR)研究了所得绿色粉末的性质。用紫外可见光谱和光致发光光谱(PL)对制备的薄膜进行了表征。纳米复合材料的XRD谱图表明,较高体积分数的晶相对应的聚苯胺聚合物具有公认的PVA单斜晶胞。透射电镜和扫描电镜图像均显示出不规则的纳米颗粒簇状排列,证明了非均匀堆积的团聚现象。EDX证实PVA-g-EI被整合到聚合物纳米复合材料的结构中。吸收边的明显变化和三个与PL无关的发射峰再次证实了PANI/PVA-g-EI形成了纳米复合材料。
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引用次数: 0
Analytic Calculation of the Critical Temperature and Estimation of the Critical Region Size for a Fluid Model 流体模型临界温度的解析计算及临界区域大小的估计
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-20 DOI: 10.15407/ujpe68.9.601
I.V. Pylyuk, M.P. Kozlovskii, O.A. Dobush
An analytic procedure for calculating the critical temperature and estimating the size of the critical region for a cell fluid model is developed. Our numerical calculations are illustrated by the case of the Morse potential parameters characterizing the alkali metals (sodium and potassium). The critical temperatures found for liquid sodium and potassium as solutions of the resulting quadratic equation agree with experimental data. The expression for the relative temperature determining the critical region size is obtained proceeding from the condition for the critical regime existence. In the cases of sodium and potassium, the value of this temperature is of the order of a few hundredths.
提出了一种计算细胞流体模型临界温度和估计临界区域大小的解析方法。我们的数值计算用碱金属(钠和钾)的摩尔斯势参数的例子来说明。所得到的二次方程解为液态钠和液态钾的临界温度与实验数据吻合。从临界区存在的条件出发,得到了相对温度决定临界区大小的表达式。在钠和钾的情况下,这个温度的值是百分之几的数量级。
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引用次数: 1
Ламелярно-ланцюгові гідрогелі: особливості структури 层状链水凝胶:结构特征
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-02 DOI: 10.15407/ujpe68.8.536
Yu.F. Zabashta, V.I. Kovalchuk, P. Kopčanský, I. Safarik, M.M. Lazarenko, L.Yu. Vergun, L.A. Bulavin
Розглядається можливiсть створення на основi бiнарного водного розчину полiмерних та олiгомерних молекул гiдрогелiв нового типу – ламелярно-ланцюгових – iз каркасом пiдвищеної жорсткостi. Запропоновано гiпотетичну модель такого каркасу, структурними елементами якого є олiгомернi ламели та полiмернi ланцюги. Цi елементи з’єднуються завдяки тому, що кiнцi полiмерних ланцюгiв втягуються в пори ламел. Отримано формулу для вiльної енергiї такої системи. Показано, що збiльшення концентрацiї полiмера має привести до взаємного зближення ламел. Цей висновок узгоджується з результатами проведеного методом малокутового розсiяння рентгенiвських променiв експерименту, в якому дослiджувались бiнарнi воднi розчини полiмера (полiетиленглiколя) та олiгомера (додецилсульфата натрiю) з рiзними концентрацiями.
本研究考虑了在聚合物和低聚物分子的二元水溶液的基础上制造一种新型水凝胶(片状链水凝胶)的可能性,这种水凝胶的框架具有更高的刚性。提出了这种框架的假想模型,其结构元素是低聚物薄片和聚合物链。由于聚合物链的末端被卷入薄片的孔隙中,因此这些元素相互连接。我们得到了这种系统的自由能公式。结果表明,聚合物浓度的增加会导致薄片相互靠近。这一结论与用小角 X 射线散射法进行的实验结果一致,该实验研究了不同浓度的聚合物(聚乙二醇)和低聚物(十二烷基硫酸钠)的二元水溶液。
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引用次数: 0
Surfaces with Lowered Electron Work Function: Problems of Their Creation and Theoretical Description. A Review 电子功函数降低的表面:产生问题及理论描述。回顾
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-02 DOI: 10.15407/ujpe68.8.549
M.V. Strikha, A.M. Goriachko
Experimental studies devoted to the creation of the modern photocathodes or efficient field emission cathodes with lowered work function or low/negative electron affinity are reviewed. We present theoretical models, where the electron affinity lowering is associated with the influence of electrically charged layers at the semiconductor/insulator interface. Modern experimental techniques of measuring the work function or the electron affinity and technologies aimed at fabricating the surfaces with low work function/electron affinity are described. In the framework of a simple theoretical model developed by the authors, it has been demonstrated that the presence of a dipole layer (e.g., composed of negatively charged oxygen ions and positively charged rare earth ions) at the semiconductor surface can lower the electron affinity by up to 3 eV provided equal concentrations of oppositely charged adsorbate ions. It is also shown that if the surface concentration of negatively charged oxygen ions is higher than the surface concentration of positively charged metal ions, the lowering of the electron affinity becomes smaller due to the upward band bending in the space charge region in the semiconductor; otherwise, the lowering of the electron affinity becomes larger due to the downward band bending. This effect allows technological proposals to be formulated for obtaining surfaces with minimum work function values in modern field-emission-based electronic devices. In the framework of the proposed model, the work function was evaluated for the OH-functionalized MXene. The corresponding value for the unfunctionalized MXene equals about 4.5 eV, being practically independent of the number of Ti and C layers (from 1 to 9 layers). The OH-functionalization lowers it down to about 1.6 eV, and this value is also practically independent of the number of atomic layers in MXene. Experimental approaches to obtain cathodes with low work function/low electron affinity are described. They are aimed at creating a spatial separation of electric charges in the near-surface cathode region perpendicularly to the surface plane. The corresponding spatial distributions of positive and negative charges are characterized by their localization either in two different atomic planes or in one plane and an extended space region (the latter variant is typical of semiconductor substrates). The technologies for producing such surfaces are based on various methods of adsorbate deposition onto the metal or semiconductor substrate: physical vapor deposition, chemical vapor deposition, liquid phase deposition, diffusion from the substrate bulk, and so forth. Particular attention is paid to the experimental works dealing with the adsorbtion of rare earth metals (Ce, Gd, Eu) and the coadsorbtion of oxygen onto the Si, Ge, and Mo surfaces (in a nano-structured state as well), which results in the dipole layer formation and the work function reduction.
本文综述了现代光电阴极或具有低功函数或低/负电子亲和的高效场发射阴极的实验研究。我们提出了理论模型,其中电子亲和力降低与半导体/绝缘体界面上带电层的影响有关。介绍了现代测量功函数或电子亲和力的实验技术,以及旨在制造低功函数/电子亲和力表面的技术。在作者建立的一个简单的理论模型框架中,已经证明了在半导体表面存在一个偶极子层(例如,由带负电荷的氧离子和带正电荷的稀土离子组成),在提供相同浓度的带相反电荷的吸附离子的情况下,可以将电子亲和力降低高达3 eV。当带负电的氧离子的表面浓度高于带正电的金属离子的表面浓度时,由于半导体中空间电荷区向上的带弯曲,电子亲和的降低变小;否则,由于带向下弯曲,电子亲和的降低会更大。这种效应允许制定技术建议,以便在现代场发射电子设备中获得具有最小功函数值的表面。在提出的模型框架内,对oh功能化MXene的功函数进行了评估。未功能化MXene的对应值约为4.5 eV,与Ti层数和C层数(从1层到9层)无关。oh功能化将其降低到约1.6 eV,并且该值实际上也与MXene中的原子层数无关。描述了获得低功函数/低电子亲和力阴极的实验方法。它们的目的是在垂直于表面的近表面阴极区域中产生电荷的空间分离。正负电荷的相应空间分布的特征是它们要么在两个不同的原子平面上定位,要么在一个平面和一个扩展的空间区域(后一种变体是半导体衬底的典型特征)。生产这种表面的技术是基于将吸附物沉积到金属或半导体衬底上的各种方法:物理气相沉积、化学气相沉积、液相沉积、衬底体扩散等。特别关注的是处理稀土金属(Ce, Gd, Eu)的吸附和氧在Si, Ge和Mo表面(也是在纳米结构状态下)的共吸附的实验工作,这导致偶极子层的形成和功函数的减少。
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引用次数: 1
The Multiscale Hybrid Method with a Localized Constraint. I. A Modified Control Volume Function for the Hybridized Mass and Momentum Equations 具有局部约束的多尺度混合方法。质量与动量混合方程的一种修正控制体积函数
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-02 DOI: 10.15407/ujpe68.8.517
M. Bakumenko, V. Bardik, D. Nerukh
A new hybrid multiscaling model has been developed on the basis of the modified control volume function. Following the two-phase analogy of the same substance, the continuum and particle representations are coupled together in the framework of the mass and momentum conservation laws. The new functional form of the control volume function is elaborated by using the continuum discretization principle based on the Delaunay triangulation. The derived mass and momentum equations possess the invariant form for both micro-scale particle and large-scale continuum representations.
在修正控制体积函数的基础上,建立了一种新的混合多尺度模型。根据同一物质的两相类比,连续统和粒子表示在质量和动量守恒定律的框架内耦合在一起。利用基于Delaunay三角剖分的连续离散化原理,阐述了控制体积函数的新函数形式。所导出的质量和动量方程对于微尺度粒子和大尺度连续体都具有不变形式。
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引用次数: 1
Вплив радіаційного опромінення на параметри полегшеної дифузії модельної медико-біологічної системи 辐照对模型生物医学系统促进扩散参数的影响
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-02 DOI: 10.15407/ujpe68.8.525
T.S. Vlasenko, D.A. Gavryushenko, K.V. Cherevko, L.A. Bulavin
В рамках нерiвноважної статистичної термодинамiки роз-винено теоретичну модель дифузiї в обмежених багато-компонентних рiдинних системах за наявностi радiацiйного опромiнення, що дозволяє визначати стацiонарнi дифузiйнi потоки з урахуванням спричинених опромiненням змiн у рiвноважнiй частинi коефiцiєнта дифузiї. Для низки модельних розчинiв проведено оцiнку ентропiйних внескiв у рiвноважну частину коефiцiєнта дифузiї, спричинених змiною термодинамiчних властивостей рiдинних систем пiд впливом радiацiйного опромiнення. Показано, що опромiнення медико-бiологiчних рiдинних систем в неперервному режимi може призводити до збiльшення насичення тканин киснем за рахунок зменшення стабiлiзацiйних ефектiв, що спостерiгаються при полегшенiй дифузiї за вiдсутностi опромiнення.
在非平衡统计热力学的框架内,建立了一个存在辐射辐照的有限多组分流体系统中的扩散理论模型,该模型可以确定静态扩散通量,并考虑到辐照引起的扩散系数平衡部分的变化。对于一些模型解,估算了在辐射辐照影响下流体系统热力学性质变化引起的扩散系数平衡部分的熵贡献。结果表明,对医用和生物流体系统进行连续辐照可导致组织氧饱和度的提高,这是因为在无辐照的情况下,促进扩散的稳定效应降低了。
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引用次数: 0
Carrier Decay Lifetimes in the Narrow-gap Hg1–xCdxTe at the Interband and Intraband Excitations 窄带Hg1-xCdxTe在带间和带内激发下的载流子衰减寿命
Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-02 DOI: 10.15407/ujpe68.8.543
S. Staryi, I. Lysjuk, O. Golenkov, Z. Tsybrii, S. Danilov, J. Gumenjuk-Sichevska, K. Andrieieva, M. Smolii, F. Sizov
The lifetimes of photoconductive decay carriers under interband and intraband excitations are studied in epitaxial layers of narrow-gap Hg1−xCdxTe (x ∼0.2). Samples with large distances (>3 mm) between small-area electrical contacts and small distances (∼10 μm) with largearea contacts (THz antennas) are studied. The lifetimes of decay carriers for intraband and interband excitations are measured and compared. It has been established that, in samples with n-type conductivity, the lifetimes are comparable (in the interval of 40 ns) for both methods of excitation. At the same time, in samples with a small distance between contacts and a large area (bow-tie antennas), contacts make the main contribution to recombination. The elimination of recombination at the contacts leads to a lifetime of ∼10−6 s.
在窄间隙Hg1−xCdxTe (x ~ 0.2)外延层中研究了光导衰变载流子在带间和带内激发下的寿命。研究了小面积电触点之间的大距离(> 3mm)和小距离(~ 10 μm)与大面积触点(太赫兹天线)之间的样品。测量和比较了带内和带间激励下衰变载流子的寿命。已经确定,在具有n型电导率的样品中,两种激发方法的寿命是相当的(在40 ns的间隔内)。同时,在触点距离小、面积大的样品(领结天线)中,触点对复合起主要作用。在触点处消除复合导致寿命为~ 10−6 s。
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引用次数: 0
Magnetogenesis in Non-Local Models during Inflation 非局部模型在膨胀过程中的磁生成
IF 0.5 Q4 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-10-02 DOI: 10.15407/ujpe68.10.647
E. V. Gorbar, T. Gorkavenko, V. Gorkavenko, O. M. Teslyk
The generation of magnetic fields during the inflation in an electromagnetic model with a non-local form factor in Maxwell’s action is studied. The equations of motion for the electromagnetic field are derived and solved. It is found that the conformal symmetry breaking due to the non-local form factor does not lead to the generation of magnetic fields during the inflation in the absence of an interaction with the inflaton field. If such a coupling takes place, then the presence of the form factor inhibits the generation of primordial magnetic fields compared to the case where the non-local form factor is absent.
研究了麦克斯韦作用中具有非局部形式因子的电磁模型在膨胀过程中磁场的产生。推导并求解了电磁场的运动方程。研究发现,在没有与胀气场相互作用的情况下,非局部形式因子导致的共形对称破缺不会导致胀气过程中磁场的产生。如果存在这种耦合,那么与不存在非局部形式因子的情况相比,形式因子的存在会抑制原始磁场的产生。
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引用次数: 0
期刊
Ukrainian Journal of Physics
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