Separate Volumes Research Articles

Effects of solids with different mineralogical compositions on the properties of olefinic fluids used for drilling pre-salt wells

This work aimed to evaluate the effect of the addition of fine solids with different mineralogical compositions on the physical properties of olefinic fluids used in pre-salt wells. The fluids were added with 5% of each mineral (clay, silica, carbonate or halite) separately and characterized by rheological properties, filtrate volume and separated volume. According to the results, bentonite act as a physical barrier, improving aged fluid behavior, leading to a 66.67% decrease in separated volume. On the other hand, halite has presented a negative effect on fluid properties and resulted in an increase of 88.89% in separated volume.

Demarcation method of safety separations for sUAV based on collision risk estimation

Maintaining safe separations is essential to achieve reliable operations for unmanned aerial vehicles (UAV). Given the escalating severity of collision risks associated with UAVs, separation criteria have emerged as foundational to both airspace design and collision avoidance strategies. However, without adequate consideration of the characteristics of small-UAV (sUAV) encounters and airspace structure, most of the existing models focus on assessing uniform separation volume with manned aircraft. This paper proposes a demarcation method of safety separation for sUAVs based on collision risk estimation. Firstly, five collision zones are developed for collision determination by considering the shape characteristics. Then, the collision risk model is established from the 3-D probability density function (PDF) with the supremum of total system error (TSE). Finally, the minimum safe separations for different encountering scenarios are demarcated by setting the threshold of risk. Simulation results testify that the selection of the collision zones and crossing angles affect the collision risk apparently. The results also demonstrate the effectiveness of separation criteria demarcated by ‘Equivalent Level of Safety’ (ELoS). Statistical analysis for 100 sampled environments shows the reliability of the proposed method, which captured the characteristics of sUAVs and could be utilized for elaborative separation framework in structured low-altitude airspace.

The effect of sodium trimetaphosphate on the physical and functional characteristics of banggai yam starch

Banggai yam starch as well as other types of starch is known to have physical and functional properties which cause the use of starch in the limited reliability industry. Therefore, it is necessary to improve physical properties by modifying the proud yam starch by phosphorylation. Research to determine the sodium trimetaphosphate (STMP) concentration wich gives the best tendency in the modification of proud yam starch by phosphorylation based on its physical and functional characteristics. Research uses a completely randomized design one factor consisting of a concentration of STMP 2, 4, 6, 8, 10, 12% and native starch as a comparison. The variable of observations included emulsion separator volume, viscosity, water holding capacity (WHC), oil holding capacity (OHC), swelling power, and solubility. The results showed that the emulsion separator volume, WHC, swelling power, and solubility starch modification is smaller than native banggai yam starch, while at viscosity starch modification is greater than native banggai yam starch. In the analysis OHC fluctuates as concentration increases. The STMP concentration that gives the best tendency is 4%. The value generated at this concentration is emulsion separator volume 90%, viscosity 577 Cp, WHC 0.94 g/g, OHC 2.84 g/g, swelling power 4.60 g/g, and solubility 0.17%.

Multi-Scale Concurrent Topology Optimization Based on BESO, Implemented in MATLAB

In multi-scale topology optimization methods, the analysis encompasses two distinct scales: the macro-scale and the micro-scale. The macro-scale refers to the overall size and dimensions of the structural domain being studied, while the micro-scale pertains to the periodic unit cell that constitutes the macro-scale. This unit cell represents the entire structure or component targeted for optimization. The primary objective of this research is to present a simplified MATLAB code that addresses the multi-scale concurrent topology optimization challenge. This involves simultaneously optimizing both the macro-scale and micro-scale aspects, taking into account their interactions and interdependencies. To achieve this goal, the proposed approach leverages the Bi-directional Evolutionary Structural Optimization (BESO) method. The formulation introduced in this study accommodates both cellular and composite materials, dealing with both separate volume constraints and the utilization of a single volume constraint. By offering this simplified formulation and harnessing the capabilities of the multi-scale approach, the research aims to provide valuable insights into the concurrent optimization of macro- and micro-scales. This advancement contributes to the field of topology optimization and enhances its applications across various engineering disciplines.

Updating Design of Tubular Electrochemical Membrane Apparatus for Increasing Separation Area and Volume of Solution for Cleaning

Updating Design of Tubular Electrochemical Membrane Apparatus for Increasing Separation Area and Volume of Solution for Cleaning

KCl-Modulated Hydration and Subsequent Thermoresponsive Behavior of Poly(sulfobetaine)-Based Diblock Copolymer Thin Films

The KCl-modulated swelling of double thermoresponsive diblock copolymer (DBC) thin films in D2O atmosphere and their subsequent responsive behavior are investigated via spectral reflectance (SR), in situ time-of-flight neutron reflectometry (ToF-NR), and Fourier-transform infrared (FT-IR) spectroscopy. The copolymer consists of a short zwitterionic (poly(4-(N-(3-methacrylamidopropyl)-N,N-dimethylammonio) butane-1-sulfonate)) (PSBP) block and a long non-ionic poly(N-isopropylmethacrylamide) (PNIPMAM) block. DBC thin films are prepared via spin-coating from solutions containing 5 mM or devoid of KCl. The addition of KCl to the DBC thin films leads to a higher swelling ratio and D2O content during vapor treatment with D2O. Upon the subsequent heating of the hydrated DBC films, the films swell further and reach a maximum thickness before contracting. Two separate volume phase transition temperatures (VPTTs) are observed, namely where a further swelling plateau is reached (VPTTfs), and where contraction starts (VPTTc). Based on complementary SR studies of the effect of KCl on the swelling behavior of the respective PSBP and PNIPMAM homopolymer thin films, we conclude that the “further-swelling” period is mainly a consequence of the UCST-type phase transition of PSBP, whereas the “film contraction” period is due to the LCST-type phase transition of PNIPMAM in thin-film geometry. We observe that KCl reduces the VPTTc of the PNIPMAM blocks. Moreover, the salt migrates or aggregates inside the thin film upon heating, thereby forming a KCl enrichment layer in the intermediate section of the film. Furthermore, the observations by FT-IR prove that macroscopic and mesoscopic D2O absorption and desorption are correlated with the effect of KCl on hydration and de-hydration of the hydrophilic groups.

Study of Injector Geometry and Parcel Injection Location on Spray Simulation of the Engine Combustion Network Spray G Injector

Abstract Parcel-based simulations are the most common method to simulate fuel sprays, especially for reacting conditions, due to their lower computational cost compared to more highly resolved simulations. It is important, however, to understand how spray boundary conditions are used to initialize the parcels that represent the atomizing fluid affect downstream conditions and overall simulation performance. Traditionally, when parcel simulations are used, the injector tip geometry is either significantly simplified or removed altogether due to resolution limits. Recent advances in computational power and numerical methods, however, have made it possible to resolve flow through these features. Previous work has shown some potential effects of even simple injector tip geometries, and this study investigates the effect of very detailed nozzle geometries on parcel-based simulations that have typically ignored these details. Four different parameters were investigated: whether a simulation includes a detailed injector tip geometry or a flat surface; whether parcels are initialized at the counterbore exit, which is more common, or at the nozzle exit; the use of an experimentally derived rate of injection or one-way coupling with a separate internal nozzle volume of fluid (VOF) simulation; the use of nominal or measured injector geometry. Simulations were compared using both global penetrations as well as local data near the injector. Spray penetration and other global measures showed limited sensitivity to boundary conditions/initialization procedure, but local data such as the local liquid volume fraction showed greater variation between the conditions, which may have an impact on mixing and combustion predictions in engine applications.

Reinforcement learning-based approach for optimizing solvent-switch processes

In chemical and pharmaceutical industries, process control optimization is a crucial step to improve economical efficiency and the environmental impact. The current state-of-practice heavily relies on expert knowledge and extensive lab experiments. This not only increases the development time but also limits the discovery of new strategies. In this study, we propose Reinforcement Learning-based optimization approach for solvent-switch processes. We utilize a digital twin as the environment for a process designed to switch the THF to 1-propanol. A reward function is created for minimizing the process time and constraints are implemented using logarithmic barrier functions. A PPO agent is trained on the environment. The agent proposed a novel strategy that combines two conventionally separate phases, evaporation and constant volume distillation. This strategy resulted in an overall cost decrease of 24.9% compared to the baseline strategy. Moreover, results were verified experimentally on a pilot plant of Johnson & Johnson (J&J).

Understanding Cultural Similarities of Archaeological Sites from Excavation Reports Using Natural Language Processing Technique

In this study, we applied natural language processing (NLP) techniques to texts of excavation reports on buried cultural properties to calculate the degree of similarity between the reports for determining archaeological sites that have a high degree of similarity. Specifically, we validated whether the similarity of sentence embeddings in the excavation reports of these sites is consistent with the existing classification. Four archaeological sites classified in existing archaeological research papers were used. For validation, 128 excavation reports from the four sites were used; sentence embeddings were obtained using Doc2Vec. We obtained the following results: 1) In applying NLP to excavation reports for determining the similarities of archaeological sites, merging the texts for each site into a single document and then processing it was more preferable than processing it in separate volumes of the excavation report. 2) The similarity based on sentence embedding of excavation reports using Doc2Vec was more consistent with the classification of the characteristics of archaeological sites than term frequency–inverse document frequency (TF-IDF). 3) When targeting a specific period, the sentence embedding exclusively for the text of the relevant period is consistent with the classification of the characteristics of the archaeological site from the artifacts and structural remains of that specific period. 4) When a specific period is targeted, the exclusive sentence embeddings of that period, obtained through the additive compositionality of sentence embeddings, can be used to classify the characteristics of archaeological sites based on the artifacts and structural remains on that period. Consequently, the similarities of texts based on NLP can reflect the similarities of archaeological sites. This holds true even for excavation reports that include spelling inconsistencies, optical character reader misrecognition, and garbled words.

Shift in Calcium From Peripheral Bone to Axial Bone After Tumor Resection in Patients With Tumor-Induced Osteomalacia.

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by excessive production of fibroblast growth factor 23 (FGF23) by a tumor. After successful tumor resection, patients can recover from hypophosphatemia quicky. However, data on the changes in bone mineral density (BMD) and microstructure in the short term after surgery remained unclear. This work aimed to investigate the postoperative changes in BMD and microstructure both in peripheral and axial bone in TIO patients. We evaluated BMD and microarchitecture in 22 TIO patients using high-resolution peripheral quantitative computed tomography (HR-pQCT) and dual-energy x-ray absorptiometry (DXA) before and 3 months after surgery in this retrospective study. In this study, a total of 22 TIO patients who had recovered serum phosphate levels postoperatively were enrolled. After surgery, areal BMD (aBMD) increased by 21.6% in the femoral neck, by 18.9% in the total hip, and by 29.5% in the lumbar spine. Moreover, TBS increased by 14.1% (all P < .001). In contrast, trabecular or cortical volumetric BMD (vBMD), and microstructure of trabecular bone (trabecular number, separation and bone volume ratio) and cortical bone (cortical thickness and porosity) at the distal radius or tibia were further deteriorated. Correlation analyses found that changes in femoral neck and total hip aBMD were both conversely associated with changes in trabecular vBMD and bone volume ratio, while positively correlated with change in trabecular separation at the distal radius. Although aBMD and microstructure in the axial bone were improved, vBMD and microstructure in the peripheral bone were further impaired shortly after surgery. Correlation of improvement of aBMD in the total hip and femoral neck with deterioration of vBMD and microstructure at the distal radius indicated a shift in calcium from the peripheral bone to the axial bone in the short term after tumor resection in TIO patients.

«Библиотека биоэтики»: вклад в развитие образования (рецензия на многотомное издание) М.: Вече, 2019–2022; Тома 1–10

The published review is devoted to ten-volume edition entitled Bioethics Library published by Veche publishing house. The series was edited by Academician Chuchalin AG. It consisted of various works related to bioethical issues. The edition is mainly intended for students and teachers of bioethics of Russian medical universities. The series has a wide historical framework. It examines the works by Avicenna and Immanuel Kant, translated books by Sweden researchers Johansson I and Lynøe N. Texts by Russian physicians and thinkers (Berdyayev NA, Veresayev VV, Uglov FG, Botkin ES, Voyno-Yasenetsky VF (St. Luka Krymsky), Pirogov NI, Pavlov IP, Koni AF, Ilyin IA, Metropolitan Antony Surozhsky, etc.) are published as well. A collection of official documents on bioethical regulation is presented as a separate volume. The edition comprises self-evaluation questions. The texts included into the Bioethics Library make the readers familiar with the history of bioethics building and formation as an anthropologic project. Bioethics is based on the value of life and human integrity, it protects the human being and society, and, as a result, possesses regulatory functions. In the edition, special attention is paid to Russian authors and their view of bioethical issues. It is assumed that examination, popularization and content analysis of the series are particularly relevant within the context of national bioethics development.

A BIOGRAPHICAL DICTIONARY OF ST. PETERSBURG CLASSICISTS IN THE 19TH - EARLY 20THCENTURY: IN THREE VOLUMES / ED. A.K. GAVRILOV. ST. PETERSBURG: BIBLIOTHECA CLASSICA PETROPOLITANA EDITION, 2021. (VOL. I: A-K (XXXVI, 1-426). VOL. II: L-YA (VI, 427-860). VOL. III: INDEXES AND APPENDICES (VIII, 861-1050)

The review presents the long-awaited book, based on years of thinking by authors about the fate of the national humanities. The dictionary has already become a fact of literary and cultural life, and its protagonists are not only the people described in it, but also the authors of essays and the editorial board, constantly discovering threads of continuity with St. Petersburg classicists. 43 authors of various philological specializations participated in the building of this, without any exaggeration, epochmaking work, which includes articles devoted to 250 St. Petersburg classicists in the 19th - early 20thcentury (scholars, tutors, translators, managers). To recreate the true image of the personage, the authors attracted a wide range of sources, namely, research papers, memoirs, correspondence and still unpublished archival materials. Collected together (although with varying degrees of detail depending on the number of extant sources), these portraits give us a comprehensive picture of the development of St. Petersburg classicism in its heyday and at the same time allow us to assess the state of intellectual forces and spiritual life of Russian society as a whole. The dictionary is convenient to use, because it is equipped with various indexes that make up a separate volume, which ends with a review essay written by the responsible editor and inspirer of the publication A.K. Gavrilov, where, among other things, the principle of material selection is analyzed in detail. The book is convenient and indispensable for work and at the same time is a fascinating reading.

RECONSTRUCTION OF THE HISTORICAL PLANNING OF THE QUARTER WITH THE FORMATION OF MODERN RESIDENTIAL BUILDINGS IN THE HISTORICAL BUILDING IN LUBEK

The article notes that the preservation of historical urban planning is an important aspect of modern urban planning, which contributes to the preservation of cultural heritage and the formation of the city's identity. However, to achieve this goal, a scientific approach is necessary, which includes a detailed analysis of the territory, research of historical archives and documents, design and implementation of plans taking into account modern requirements for urban planning. The article pays special attention to historical styles of planning quarters and districts, particularly in old cities such as Kyiv. It is noted that preservation of historical urban planning can be a difficult task due to the fact that it often does not meet modern requirements, for example, to ensure the comfort of residents and insolation. Therefore, it is important to strike a balance between the preservation of the historical territory and compliance with modern urban planning requirements. In general, the article provides clear examples of how historical urban planning can be preserved and ensured its compliance with modern requirements of urban planning, which is an important element of the formation of the cultural heritage and identity of the city.&#x0D; In addition, the article compares different approaches to the development of urban planning in new districts of European cities, in particular, Amsterdam and Kyiv. Attention is drawn to the development of green areas and open spaces in new districts and their harmonious combination with historical planning. An example of a new district of modern housing in Amsterdam is given, which continues the theme of the development of quarter buildings of the city's historical planning.&#x0D; Special attention is paid in the article to the problem of restoration of historical planning in the districts of the old city. The example of the "Founding Quarter" of the German city of LЯbeck is used to analyze this issue. The reasons for the destruction of the historical core of the city, the modernist features of reconstruction in the post-war period are considered and analyzed. The modern project of restoration of this district with the return of historical streets, layout of buildings, their separate volumes was analyzed.

The structure and energy of symmetric tilt grain boundaries in tungsten

Considering the limitations of experiments and the necessity for improving the radiation resistance of materials based on the grain boundary (GB) engineering, more complete results on underlying GB properties are not yet available, and the correlations between such properties remain to be figured out. Here, we constructed a systematical database of the basic properties of 113 distinct symmetric tilt grain boundaries (STGBs) with 〈100〉, 〈110〉, and 〈111〉 axes in tungsten, including the GB energy, work of separation, excess volume and a single vacancy/interstitial segregation energy, calculated by molecular statics simulations with six interatomic potentials. Then, the correlations between these parameters were systematically investigated. We found that although the magnitude of GB properties yielded by these potentials is different, the correlations between these parameters are consistent with each other. According to the analysis of dislocations in these STGB's stable structures, we divided these STGBs into two categories, namely GBs consisting of discrete and overlapping dislocations (DDGBs vs. ODGBs), and identified the dislocation type, i.e., 〈100〉, 〈110〉, and 1/2〈111〉 dislocations, and threshold angles. For DDGBs, the work of separation and excess volume are negatively and positively proportional to the GB energy, respectively, while the minimal vacancy/interstitial segregation energy is close to a constant value for the STGBs consisting of the same dislocations. For ODGBs, there is no obvious correlation between these parameters. In addition, we found that the main contribution to the excess volume is within 5 Å around the GB, and the minimal vacancy/interstitial segregation energy of 〈110〉 STGBs is lower than 〈100〉 and 〈111〉 STGBs, showing a greater capture ability for vacancies/interstitials. We also confirmed that, in Fe and W, STGBs with the same crystallography have strongly correlated energies, which can be scaled by the cohesive energy or different shear moduli, depending on the chosen potential.

In depth characterisation of hydrocyclones: Ascertaining the effect of geometry and operating conditions on their performance

Hydrocyclones are used for densification of waste streams prior to drying or for classification of solid and liquids in two-phase streams. They are becoming popular in industrial units due to their simplicity, low energy consumption and high versatility. However, the effect of geometry and operating conditions on the cut diameter and solid recovery efficiency have been independently studied, and therefore there are no studies approaching the influence of all the parameters simultaneously. Thus, a detailed experimental study was conducted to ascertain the effect of the hydrocyclone body (diameter and angle) and the vortex finder and spigot size and shape, as well as operating conditions (inlet pressure and solid concentration) on the separation efficiency curve, cut diameter, solid and volume recovery and the main features of the outlet streams. It has been proven that separation efficiency and outlet stream composition are sensitive to both the geometry of the hydrocyclone and the operating parameters. Therefore, knowledge of their influence is essential for the design of industrial units where liquid reutilisation is a major concern.

Assessing reservoir connectivity with pressure/rate surveillance data

Estimating reservoir connectivity is critical for assessing infill-drilling prospects and initiating fluid injection in enhanced oil recovery operations. Several methods have appeared in the literature over decades to meet these business needs, given that all tools, including seismic imaging, have limitations. Besides imaging, geochemical fingerprinting constitutes a powerful tool to gauge the compartmentalization question. However, real-time pressure/rate surveillance data allows assessing interwell connectivity vis-à-vis the overall drainage volume. This study presents a simplified approach to using the reciprocal-productivity index (RPI) vs. the total-material-balance time ( t ¯ T M B ) plot. This tool exhibits the same slope for those wells in the same compartment beyond the start of the boundary-dominated flow (BDF) period. The wells showing different slopes imply that they are in separate drainage volumes. The early-time transient period remains muted to minimize confusion on this Cartesian plot. We validated the proposed tool's efficacy with 2D and 3D models with increased degrees of reservoir complexity, followed by the verification phase with four field examples. The use of other analytical tools complemented our findings.

Platelet-rich fibrin combined with new bone graft material for mandibular defect repair: A in vivo study on rabbits.

Insufficient bone mass is still a difficult point to be solved in oral implantation, so new bone graft materials are continuously researched and discussed in clinical practice in order to obtain better bone augmentation. In order to explore whether platelet-rich fibrin (PRF) can promote the formation of new bone in mineralized collagen (MC), MC/PRF and pure MC were implanted into the bilateral mandibular defect model in rabbits, respectively. Micro-CT scan and histological evaluation of the target area at 4, 8, and 12 weeks after operation. The results of Micro-CT three-dimensional reconstruction analysis showed that the ratio of bone volume to total volume (BV/TV), trabecular bone number (Tb.N), trabecular bone thickness (Tb.Th) and trabecular bone separation (Tb.Sp) and residual material volume fraction (RMVF) in the MC/PRF group were better than those in the MC group (p<0.05). The results of HE and Masson staining showed that the new bone formation and material degradation rate of the MC/PRF group were better than those of the MC group. The results suggest that PRF can accelerate the formation of new bone in MC, and provide new ideas for the clinical application of new bone graft materials.

Capillary forces and capillary bridges between a three-finger microgripper and a plate

ABSTRACT The presence of surface tension in liquids, which induces a strong capillary force between wetting particles in micro/nano scale, has aroused extensive attention. In present study, a fundamental investigation on capillary forces and rupture behaviors of capillary bridges between a three-finger microgripper and a plate is conducted in quasi-static state. Theoretical analysis is performed for solutions of the capillary force. The capillary bridges between a three-finger microgripper and a plate are established based on the principle of energy minimization. An analytical approach for computing the capillary force for the three-finger/plate geometry is proposed by means of variables obtained from the simulation models. The comparison of the single-finger capillary bridge and three-finger capillary bridge is investigated based on the developed models. The effects of separation distance, capillary bridge volume, radial distance and contact angle on the capillary force of three-finger capillary bridges are analyzed in detail. The results demonstrate that the variation of capillary force with separation distance and volume changing is not monotonic, which is caused by the edge effect of the three-finger microgripper. Capillary force measurements were experimentally characterized to demonstrate the reliability of the simulation models and the capillary force solution method based on an established experimental platform.

Facts to Consider in Developing Materials That Emulate the Upper Jawbone: A Microarchitecture Study Showing Unique Characteristics at Four Different Sites.

The maxilla is generally acknowledged as being more trabecular than the mandible. Allograft currently available for use in the maxillofacial region is harvested from the hip and long bones, irrespective of their local characteristics, and grafted onto the jawbones. Other alternative are autograft or commercially available bone substitutes. Due to their inherent differences, an in-depth understanding of the bone microarchitecture is important to develop the most compatible graft for use at the maxilla. This cross-sectional study aimed to determine the microstructures of bone harvested from different sites of the maxilla, to be used for standard setting. Forty-nine specimens from seven human cadavers were harvested from the zygomatic buttress, anterior maxillary sinus wall, anterior nasal spine and anterior palate. Each bone block, measuring of 10 mm × 5 mm, was harvested using rotary instruments. Bone analysis was performed following micro-computed tomography to obtain trabecular number (Tb.N), trabecular separation (Tb.Sp), trabecular thickness (Tb.Th), and bone volume fraction (BV/TV). There were site-related differences, with BV/TV that ranged between 37.38% and 85.83%. The Tb.N was the lowest at the palate (1.12 (mm-1)) and highest at the anterior maxillary sinus wall (1.41 (mm-1)) region. The palate, however, had the highest trabecular separation value (Tb.Sp) at 0.47 mm. The TB.Th was the lowest at the anterior nasal spine (0.34 mm) but both the zygoma and anterior maxillary sinus regions shared the highest Tb.Th (0.44 mm). Except for having the lowest Th.Sp (0.35 mm), the anterior maxillary sinus wall consistently showed higher values together with the zygomatic buttress in all other parameters. Concurring with current clinical practice of harvesting autograft from the zygomatic buttress and anterior maxillary sinus wall, their bony characteristic serve as the microarchitecture standard to adopt when developing new bone graft materials for use in the maxilla.

On a geometric combination of functions related to Prékopa–Leindler inequality

AbstractWe introduce a new operation between nonnegative integrable functions on , that we call geometric combination; it is obtained via a mass transportation approach, playing with inverse distribution functions. The main feature of this operation is that the Lebesgue integral of the geometric combination equals the geometric mean of the two separate integrals; as a natural consequence, we derive a new functional inequality of Prékopa–Leindler type. When applied to the characteristic functions of two measurable sets, their geometric combination provides a set whose volume equals the geometric mean of the two separate volumes. In the framework of convex bodies, by comparing the geometric combination with the 0‐sum, we get an alternative proof of the log‐Brunn–Minkowski inequality for unconditional convex bodies and for convex bodies with n symmetries.