Tailoring electronic properties of multilayer phosphorene by siliconization

Controlling a thickness dependence of electronic properties for two-dimensional (2d) materials is among primary goals for their large-scale applications. Herein, employing a first-principles computational approach, we predict that Si interaction with multilayer phosphorene (2d-P) can result in the formation of highly stable 2d-SiP and 2d-SiP$_2$ compounds with a weak interlayer interaction. Our analysis demonstrates that these systems are semiconductors with band gap energies that can be governed by varying the thickness and stacking order. Specifically, siliconization of phosphorene allows to design 2d-SiP$_x$ materials with significantly weaker thickness dependence of electronic properties than that in 2d-P and to develop ways for their tailoring. We also reveal the spatial dependence of electronic properties for 2d-SiP$_x$ highlighting difference in effective band gaps for different layers. Particularly, our results show that central layers in the multilayer 2d systems determine overall electronic properties, while the role of the outermost layers is noticeably smaller

Straintronics in Phosphorene: Tensile vs Shear Strains and Their Combinations for Manipulating the Band Gap

We study the effects of the uniaxial tensile strain and shear deformation as well as their combinations on the electronic properties of single-layer black phosphorene. The evolutions of the strain-dependent band gap are obtained using the numerical calculations within the tight-binding (TB) model as well as the first-principles (DFT) simulations and compared with previous findings. The TB-model-based findings show that the band gap of the strain-free phosphorene agrees with the experimental value and linearly depends on both stretching and shearing: increases (decreases) as the stretching increases (decreases), whereas gradually decreases with increasing the shear. A linear dependence is less or more similar as compared to that obtained from the ab initio simulations for shear strain, however disagrees with a non-monotonic behaviour from the DFT-based calculations for tensile strain. Possible reasons for the discrepancy are discussed. In case of a combined deformation, when both strain types (tensile/compression + shear) are loaded simultaneously, their mutual influence extends the realizable band gap range: from zero up to the values respective to the wide-band-gap semiconductors. At a switched-on combined strain, the semiconductor-semimetal phase transition in the phosphorene is reachable at a weaker (strictly non-destructive) strain, which contributes to progress in fundamental and breakthroughs.Comment: 16 pages,5 figures, 1 tabl

emacs-gc-stats: Does garbage collection actually slow down Emacs?

<p>This dataset contains raw data, reproducible analysis (Org file), and presentation sources (Org file) for "emacs-gc-stats: Does garbage collection actually slow down Emacs?" presented at EmacsConf 2023: <a href="https://emacsconf.org/2023/talks/gc/">https://emacsconf.org/2023/talks/gc/</a></p><p>The file structure (inside the compressed emacs-gc-stats.tar.gz):</p><ol><li>analysis.org contains the Org sources to generate all the plots</li><li>presentation.org contains the Org source of the presentation</li><li>0.eld - 129.eld contain the raw submitted data</li><li>*.svg files are annotated graphs prepared for the presentation</li><li>gc-duration/ contains processed statistics of GC duration</li><li>gc-duration-evo/ contains statistics of GC evolution over time</li><li>gc-merged/ contains statistics of agglomerated GCs</li><li>gc-pause/ contains statistics of GC frequency</li><li>dat/ contains filtered raw data in tabulated format prepared for Gnuplot</li></ol><p> </p&gt

Measuring the Pull-Off Force of an Individual Fiber Using a Novel Picoindenter/Scanning Electron Microscope Technique

We employed a novel picoindenter (PI)/scanning electron microscopy (SEM) technique to measure the pull-off force of an individual electrospun poly(vinylidene fluoride) (PVDF) fibers. Individual fibers were deposited over a channel in a custom-designed silicon substrate, which was then attached to a picoindenter. The picoindenter was then positioned firmly on the sample stage of the SEM. The picoindenter tip laterally pushed individual fibers to measure the force required to detach it from the surface of substrate. SEM was used to visualize and document the process. The measured pull-off force ranged between 5.8 ± 0.2 μN to ~17.8 ± 0.2 μN for individual fibers with average diameter ranging from 0.8 to 2.3 μm. Thus, this study, a first of its kind, demonstrates the use of a picoindenter to measure the pull-off force of a single micro/nanofiber

Institutional environment for financial provision of small agricultural business entities of Ukraine

The purpose of the study is to assess the institutional environment and determine the need for financing small agricultural businesses in Ukraine in order to facilitate access to financial resources in accordance with the need. The information base of the study is the regulatory and legal framework of state support for the agricultural industry, analytical studies of information agencies, data from the State Statistics Service of Ukraine and Ministry for Development of Economy, Trade and Agriculture of Ukraine. The data on the planned and actual indicators of budget expenditures for agricultural development were obtained on the basis of an analysis of the reports posted on the official website of the State Budget of Ukraine. The study determined the market capacity by financing the activities of small agricultural enterprises by sources and state support. An attempt has been made to outline the technology for a comprehensive assessment of the need for financing peasant and small farms in Ukraine through determining the capacity of financing the industry. As a result, it was established that the annual demand for resources for this type of entrepreneurship is at least UAH 370 billion, and in the near future it will grow at least UAH 26.5 billion annually. Particular attention is paid to the areas of micro crediting and state support for the development of small businesses in rural areas. The practical significance of the study lies in the fact that the implementation of the results of research work allows the implementation of technological support for the formation of a financing system for small agricultural entrepreneurship. This is necessary for the technical justification of state programs for the development of small business, strategies for the development of rural areas, state regulation of the development of the agricultural sector

Шкільний підручник як об’єкт педагогічного дослідження

Abstract. The article deals with investigations of scientists in the field of school textbook theory. The material has been structured taking into account the main components of this field of knowledge: purpose (the dual essence of this type of educational literature has been revealed – it is a carrier of educational content and teaching aids; position of the textbook as a model of integral learning process has been substantiated (systematization, consolidation and control, self-education, integrating, coordinating, developmental-educational), structure (general didactic structure of the school textbook covers the text and non-text components – the apparatus of mastering, illustrative material, orientation apparatus), methods of analysis and evaluation (distinguish traditional and theoretical) – analytical and formalized methods; the structural-functional approach to the textbook analysis has been proved). The peculiarities of textbooks for elementary school have been analyzed: the most complete definition of this phenomenon has been formulated; the leading functions of the textbook addressed to junior students have been defined – informational, developmental, educational, motivational; the features of structural components (taking into account the age of students) have been specified; methods of analysis and evaluation of the textbook have been classified: methods of analysis of the manuscript, methods of evaluation of the textbook itself, diagnostic evaluation ex post facto; a comprehensive approach to the analysis of textbooks for elementary school has been proposed; methods of analysis of certain aspects of the textbook (motivational component, developmental orientation, etc.) have been offered.Анотація. У статті йдеться про дослідження вчених у галузі теорії шкільного підручника. Матеріал структуровано з урахуванням основних компонентів цієї галузі знань: мети ( виявлено подвійну сутність цього виду навчальної літератури – вона є носієм навчального змісту та засоби навчання; обґрунтовано положення підручника як моделі цілісного процесу навчання (систематизація, закріплення та контроль, самоосвіта, інтегруюча, координуюча, розвиваюча-виховна), структура (загальнодидактична структура шкільного підручника охоплює текстовий і позатекстовий компоненти – апарат засвоєння, ілюстративний матеріал, орієнтаційний апарат), методи аналізу та оцінювання (розрізняють традиційні та теоретичні) – аналітичні та формалізовані методи; доведено структурно-функціональний підхід до аналізу підручника). Проаналізовано особливості підручників для початкової школи: сформульовано найбільш повне визначення цього явища; провідні функції підручника адресовані молодшим школярам визначено – інформаційні, розвиваючі, навчальні, мотиваційні; в уточнено особливості структурних компонентів (з урахуванням віку учнів); методи аналізу та оцінки підручника були класифіковані: методи аналізу рукопису, методика оцінка самого підручника, діагностична оцінка постфактум; комплексний підхід до аналізу запропоновано підручників для початкової школи; методи аналізу окремих сторін підручника (мотиваційний компонент, розвивальна спрямованість тощо).The article deals with investigations of scientists in the field of school textbook theory. The material has been structured taking into account the main components of this field of knowledge: purpose (the dual essence of this type of educational literature has been revealed – it is a carrier of educational content and teaching aids; position of the textbook as a model of integral learning process has been substantiated (systematization, consolidation and control, self-education, integrating, coordinating, developmental-educational), structure (general didactic structure of the school textbook covers the text and non-text components – the apparatus of mastering, illustrative material, orientation apparatus), methods of analysis and evaluation (distinguish traditional and theoretical) – analytical and formalized methods; the structural-functional approach to the textbook analysis has been proved). The peculiarities of textbooks for elementary school have been analyzed: the most complete definition of this phenomenon has been formulated; the leading functions of the textbook addressed to junior students have been defined – informational, developmental, educational, motivational; the features of structural components (taking into account the age of students) have been specified; methods of analysis and evaluation of the textbook have been classified: methods of analysis of the manuscript, methods of evaluation of the textbook itself, diagnostic evaluation ex post facto; a comprehensive approach to the analysis of textbooks for elementary school has been proposed; methods of analysis of certain aspects of the textbook (motivational component, developmental orientation, etc.) have been offered.У статті йдеться про дослідження вчених у галузі теорії шкільного підручника. Матеріал структуровано з урахуванням основних компонентів цієї галузі знань: мети (виявлено подвійну сутність цього виду навчальної літератури – вона є носієм навчального змісту та засоби навчання; обґрунтовано положення підручника як моделі цілісного процесу навчання (систематизація, закріплення та контроль, самоосвіта, інтегруюча, координуюча, розвиваюча-виховна), структура (загальнодидактична структура шкільного підручника охоплює текстовий і позатекстовий компоненти – апарат засвоєння, ілюстративний матеріал, орієнтаційний апарат), методи аналізу та оцінювання (розрізняють традиційні та теоретичні) – аналітичні та формалізовані методи; доведено структурно-функціональний підхід до аналізу підручника). Проаналізовано особливості підручників для початкової школи: сформульовано найбільш повне визначення цього явища; провідні функції підручника адресовані молодшим школярам визначено – інформаційні, розвиваючі, навчальні, мотиваційні; в уточнено особливості структурних компонентів (з урахуванням віку учнів); методи аналізу та оцінки підручника були класифіковані: методи аналізу рукопису, методика оцінка самого підручника, діагностична оцінка постфактум; комплексний підхід до аналізу запропоновано підручників для початкової школи; методи аналізу окремих сторін підручника (мотиваційний компонент, розвивальна спрямованість тощо)

Microbiological Activity of Soil Under the Influence of Post-Harvest Siderates

The results of research on the activation of the microflora by using post-harvest green manure crops were presented. As a result of the conducted studies, the positive effect of sidereal crops of Raphanus sativum and Phacelia tanacetifolia on activity increase of microflora in black soil with little humus was revealed. Application of post-harvest siderates increased the number of non-sporous species of bacteria and actinomycetales, contributed to improvement of soil environment under the influence of siderates, which had a positive effect on creating more comfortable conditions for growing potatoes. The usage of green fertilizers had a positive influence on microbiology activity of soil

In situ clamped beam bending of physical vapor deposited Cu/Nb nanolaminate with 20 nm individual layer thickness

<p>In situ scanning electron microscope (SEM) videos of clamped beam bending of Cu/Nb PVD nanolaminate with 20 nm layer thickness and 42+-10 nm grain size at the surface layer. Each video contains the video captured with SEM and the corresponding measured load vs. displacement curve.</p> <p>The beams were fabricated using focused ion beam (FIB) milling from the Cu/Nb sample produced in Los Alamos National Lab, USA. The sample was made using magnetron sputtering, described in ref. [1]. </p> <p>Each beam has a rectangular notch located in the center of the beam length. Each notch spans through the beam width.  Owing to limited accuracy of FIB, the notch depth was not always same at the front and rear sides of the beam (typically, smaller at the rear sides)</p> <p>Beam geometries:</p> <p>Id | Length, µm | Width, µm | Thickness, µm | Notch depth (front), nm | Notch width (front), nm</p> <p>PVD1 | 29 | 5 | 1.6 | 380 | 120</p> <p>PVD2 | 29 | 5 | 1.5 | 290 | 305</p> <p>All the beams were loaded using Hysitron PI85 picoindenter with truncated cone shape (5 µm diameter). The indenter tip was aligned with the notch location and the middle of beam width. </p> <p>All the beams were loaded under displacement control with displacement rates between 2nm/s to 10nm/s until failure.</p> <p>The SEM videos were captured using JEOL JSM-7600F SEM. </p> <p>[1] D. Bhattacharyya et al. “Transmission electron microscopy study of the deformation behavior of Cu/Nb and Cu/Ni nanoscale multilayers during nanoindentation”. In: Journal of Materials Research 24.3 (2009), pp. 1291-1302. </p