Analytical Estimates of the Water Drop Spreading Process with Percolation Effect

2020 ◽  
pp. 61-65
Author(s):  
Anatoly H. Adzhiev ◽  
Vadim N. Lesev ◽  
Gennady V. Kupovykh
Keyword(s):  
Water Drop ◽  
Contact Spot ◽  
Water Soluble ◽  
Spreading Process ◽  
Theoretical Evaluation ◽  
Percolation Effect ◽  
Loss Of Mass ◽  
Two Phases ◽  
Horizontal Substrate ◽  
New Phase

To solve the problems of active influence on thunderstorm clouds, the physical mechanism of artificial formation of water and ice germs in the cloud environment is theoretically studied. Based on the Gibbs-Vollmer theory of new phase formation, it follows that the defining parameters in the formation of embryos are the interphase energies at the vapor - water - reagent boundaries and the wetting edge angle. The active process of water spreading over a water-soluble flat horizontal substrate is studied using analytical methods. It is established that the process of interfacial interaction is metastable, in addition, the spreading process is characterized by the presence of direct contact zone between two phases in which the formation of a new compound is delayed. A theoretical evaluation of individual parameters of the system under gravitational spreading without the influence of other external fields is made. Two problems were solved: determining the dynamics of the free surface of the liquid phase and finding the boundaries of liquid propagation in the substrate. An analytical expression defining the contact angle is obtained. It is shown that the expressions defining the process main parameters of spreading a drop with simultaneous impregnation of the substrate, accompanied by a loss of mass of the liquid through the contact spot on the border of the two phases, are almost equivalent to the relations describing the process of mass loss when spreading an easily evaporating liquid.

Theoretical Evaluation of Rheological State of Sand Cement Composite Systems with Polyoxyethylene Additive Using Topological Dynamics Concept

2016 ◽  
Vol 871 ◽  
pp. 96-103 ◽  
Author(s):  
Vladimir Erofeev ◽  
Aleksandr Bobryshev ◽  
Aleksandr Lakhno ◽  
Lenar Shafigullin ◽  
Ilnaz Khalilov ◽  
...  
Keyword(s):  
Water Solution ◽  
Cement Composite ◽  
Water Soluble ◽  
Viscosity Data ◽  
Active Components ◽  
Theoretical Evaluation ◽  
Composite Systems ◽  
Polymer Powder ◽  
Cement System ◽  
Phase Water

Presents the results of studies of contemporary materials in the field of rheological state. The topological mortar structure has been provided by theoretical evaluation of the rheological state of the cross-linked solutions and the experimental viscosity data of the sand cement mortar which has been modified by water-soluble additive – polyoxyethylene. The general model has been made for the structure of non-Newtonian liquideous systems including dilatant, pseudoplastic bodies with two main rheological active components in their structure – rigid and viscous phases. It is shown that in pseudoplastic systems, as the shear stress increases, the viscous phase grows because of the reduction of rigid phase content. In dilatant systems the converse situation has been observed. Furthermore, these phases are not clearly distinguishable, but to the contrary they are spatially interconnected in a complex way. The structure modeling has been made for non-Newtonian bodies using the Shklovskii-de Gennes model. The studies have found that the construction composite sand cement system is defined as the pseudoplastic body where cement and sand act as the rigid phase, water solution of polyoxyethylene – as the viscous phase. These findings can be used to prove the influence of polymer powder on the workability of dry mortar.

scholarly journals Regeneration through Design. Comparing old and new phases of urban renewal strategies

2016 ◽  
Author(s):  
Carla Sedini ◽  
Marina Parente ◽  
Giuliano Simonelli
Keyword(s):  
Second Phase ◽  
Heavy Industry ◽  
Urban Structures ◽  
Strategic Design ◽  
Italian Case ◽  
Design Culture ◽  
Two Phases ◽  
Industry Sectors ◽  
New Phase ◽  
Wool Industry

In the last years, a new phase of economic crisis, which is concerning sectors of manufacturing industries, is affecting Europe. Focusing on Italy, sectors which have strongly characterized our country, such as textile and accessories, are facing with an fluctuating period of crisis. Also in this case, as it happened from late ‘80s, the urban structures and identities are seriously affected and need interventions of regeneration in order to gain new life both from social, productive and commercial point of views. Having in mind the Italian case, while the first phase identified had the characteristics of a disruptive macro-phenomenon, the second phase is more subtle and gradual. In this paper we are going to focus on changes of design culture in light of these urban phenomena. While we can already make a first evaluation of regeneration projects developed after the crisis of heavy industry sectors, the most recent events of industrial recession and the consequent regeneration of the correspondent empty areas are still ongoing. In order to analyze and, where it is possible, compare these two phases, we are going to look at two Italian case studies. The first is Bicocca, an area of Milan, which in the ‘90s was interested by a massive plan of regeneration and transformation after the closure of Breda and Pirelli industries. The second is Biella, a Piedmont Province city, which has been one of the most important centers for the textile and wool industry; the crisis of this sector strongly emerged in the first years on 2000 even if it had already begun between ‘80s and ‘90s when the biggest textile factories closed down. The differences between these two examples are not merely physical and dimensional but are clearly influenced by a different timing in the regeneration processes, which occurred in these areas (or, in the case of Biella, is still occurring). The analysis proposed in this paper will be focus on the action-research developed within two didactic experiences. Notwithstanding the distinctions in terms of objectives and actors involved, in this paper we are going to delineate a systemic approach to study and design for the regeneration, improvement and innovation of places. We will try to understand if, through strategic design, it is possible to identify those soft levers and interventions able to rejoin the pieces of places, which lost their functionality and identity.DOI: http://dx.doi.org/10.4995/IFDP.2016.3284

ChemInform Abstract: Water-Soluble Dinuclear Rhodium Complexes as Catalytic Precursors for the Hydroformylation of Alkenes in a Two Phases System.

ChemInform ◽  
1989 ◽  
Vol 20 (6) ◽  
Author(s):  
P. KALCK ◽  
P. ESCAFFRE ◽  
F. SEREIN-SPIRAU ◽  
A. THOREZ ◽  
B. BESSON ◽  
...  
Keyword(s):  
Water Soluble ◽  
Rhodium Complexes ◽  
Two Phases

scholarly journals EXTRACTION AND REEXTRACTION OF HISTIDINE AND RIBOFLAVIN BY N-VINYLCAPROLACTAME COPOLYMERS WITH 1-VINYL- AND 1-METHACRYLOYL-3,5-DIMETHYLPYROZOLE

2018 ◽  
Vol 59 (7) ◽  
pp. 55
Author(s):  
Maria S. Lavlinskaya ◽  
Gennadiy V. Shatalov ◽  
Nadezhda Ya. Mokshina ◽  
Oksana A. Pakhomova ◽  
Vyacheslav A. Kuznetsov
Keyword(s):  
Free Radical ◽  
Uv Spectroscopy ◽  
Aqueous Media ◽  
Radical Copolymerization ◽  
Water Soluble ◽  
Solution Temperature ◽  
Free Radical Copolymerization ◽  
Critical Solution Temperature ◽  
Two Phases ◽  
Degree Of Extraction

Copolymers of N-vinylcaprolactam (VC) with 1-vinyl-3,5-dimethylpyrazole (VDMP) and 1-methacryloyl-3,5-dimethylpyrazole (MDMP) were synthesized by free radical copolymerization  in dioxane with azodiisobutironitrole as initiator. Both water-soluble and water-insoluble copolymers were obtained. The copolymers compositions were determined by FTIR and UV-spectroscopy. The copolymerization constants were calculated and they were: for VC (М1)–VDMP, r1 = 0.65 ± 0.03, r2 = 0.43 ± 0.03; for VC (М1)–MDMP, r1 = 0.79 ± 0.04, r2 = 0.21 ± 0.02. These values show that VC (М1) exhibits somewhat higher activity compared to М2 and that the tendency toward alternation of comonomer units is more pronounced in VC–MDMP copolymers (r1r2 = 0.17) compared to VC–VDMP copolymers (r1r2 = 0.27). It was found that VC–VDMP copolymers are water-soluble at VC content higher than 75 mol %, and VC–MDMP copolymers at VC content higher than 88 mol %. The water-soluble copolymers based on VC have lower critical solution temperature. Their values are in range of 54-69 °C. Two-phases water-salts systems based on synthesized water-soludle thermoresponsive copolymers are proposed for histidine and riboflavin (re)extraction in aqueous media. It was found that extraction systems based on VC-VDMP copolymers are more efficient then VC-MDMP systems. Degree of extraction for both substances in a case of VC-VDMP copolymers achieved 96%. Reextraction carried out by thermoprecipitation of VC (co)polymers. It was shown that reextraction is more efficient at pH 7.6 and its degree achieved 61.7 % for histidine.

Chemical twinning in the Ti4C2S2-TiS system

1993 ◽  
Vol 51 ◽  
pp. 744-745
Author(s):  
Mingjian Hua ◽  
C. I. Garcia ◽  
A. J. DeArdo
Keyword(s):  
Interstitial Free ◽  
Low Carbon ◽  
Transformation Mechanism ◽  
Direct Transformation ◽  
Center Layer ◽  
Heating Treatment ◽  
Two Phases ◽  
Multi Phase ◽  
New Phase ◽  
Cast Condition

Titanium carbosulfide Ti4C2S2 (H phase, P63/mmc, a=0.321 nm and c= 1.120) are TiS (Rm, a=0.3417 nm and c = 2.65) are frequently found to coexist within composite particle in ultra-low carbon interstitial-free (IF) steels. This more suggest that a direct transformation from TiS to Ti4C2S2 may be a major stabilization of C at higher temperatures in these steels. The deduced orient between Ti4C2S2 and TiS is in agreement with a reported crystal structure mode transformation mechanism between these two phases appears to be strongly related structures.At the as-cast condition, most of the S- and C-rich particles in the studied IF step as pure M4C2S2 (M=Ti, Nb). After a re-heating treatment at 1300°C, M4C2S2 discharge and a new phase were observed. This new phase can be indexed as a trigonated with a=0.33 nm and c=5.3 nm (Figure 1). After a second re-heating treatment appeared at the center layer of the multi-phase particles (Figure 2). It should be noted that (i) some planar defects were observed inside the new phase and Ti4C2S2 carbon and 2a).

scholarly journals Selenized Plant Oil Is an Efficient Source of Selenium for Selenoprotein Biosynthesis in Human Cell Lines

Nutrients ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1524 ◽  
Author(s):  
Jordan Sonet ◽  
Maurine Mosca ◽  
Katarzyna Bierla ◽  
Karolina Modzelewska ◽  
Anna Flis-Borsuk ◽  
...  
Keyword(s):  
Cell Lines ◽  
Human Cell ◽  
Redox Homeostasis ◽  
Antineoplastic Agent ◽  
Water Soluble ◽  
Residual Water ◽  
Human Cell Lines ◽  
Cellular Functions ◽  
Plant Oil ◽  
Two Phases

Selenium is an essential trace element which is incorporated in the form of a rare amino acid, the selenocysteine, into an important group of proteins, the selenoproteins. Among the twenty-five selenoprotein genes identified to date, several have important cellular functions in antioxidant defense, cell signaling and redox homeostasis. Many selenoproteins are regulated by the availability of selenium which mostly occurs in the form of water-soluble molecules, either organic (selenomethionine, selenocysteine, and selenoproteins) or inorganic (selenate or selenite). Recently, a mixture of selenitriglycerides, obtained by the reaction of selenite with sunflower oil at high temperature, referred to as Selol, was proposed as a novel non-toxic, highly bioavailable and active antioxidant and antineoplastic agent. Free selenite is not present in the final product since the two phases (water soluble and oil) are separated and the residual water-soluble selenite discarded. Here we compare the assimilation of selenium as Selol, selenite and selenate by various cancerous (LNCaP) or immortalized (HEK293 and PNT1A) cell lines. An approach combining analytical chemistry, molecular biology and biochemistry demonstrated that selenium from Selol was efficiently incorporated in selenoproteins in human cell lines, and thus produced the first ever evidence of the bioavailability of selenium from selenized lipids.

scholarly journals Сравнительное исследование электрохромных свойств слоев полианилин-поликислота, нанесенных методами спрей-распыления и полива с добавлением углеродных нанотрубок

2022 ◽  
Vol 48 (2) ◽  
pp. 47
Author(s):  
А.А. Некрасов ◽  
О.Л. Грибкова ◽  
Т.В. Кривенко
Keyword(s):  
Spray Coating ◽  
Water Soluble ◽  
Coating Technology ◽  
Coating Method ◽  
Horizontal Substrate ◽  
Single Wall Nanotubes

The influence of coating method (spray-coating or drop-casting onto horizontal substrate) on the electrochromic characteristics of the layers of water-soluble polyaniline-polyacid complex was investigated. It was shown that in case of addition of single-wall nanotubes the polyaniline-polyacid layers prepared by scalable spray-coating technology demonstrate high coloration speed an electrochromic efficiency.

Theoretical Evaluation of Heavy Metals Migration and Sorption in Soil

2017 ◽  
Author(s):  
Vaidotas Danila ◽  
Saulius Vasarevičius
Keyword(s):  
Heavy Metals ◽  
Electrostatic Force ◽  
Organic Soil ◽  
Toxic Heavy Metals ◽  
Theoretical Evaluation ◽  
Toxic Pollutants ◽  
The Past ◽  
Two Phases ◽  
Soil Influence ◽  
Heavy Metals In Soils

Heavy metals are one of the group of toxic pollutants in the soil. Over the past years, many researches have been conducted on the migration of heavy metals in soils and various models were developed in order to study the mobility of toxic heavy metals. The convection-dispersion equation is the most commonly used equation for describing the migration of toxic pollutants in the soil. Various properties of the soil influence the mobility of heavy metals: soil pH, texture, sorption character-istics. Heavy metals not only migrate in the soil, but also interact with mineral and organic soil particles. The mobility of heavy metals in soils is determined by their partitioning between solid and aqueous phases of the soil. The partitioning of heavy metals between these two phases are described by sorption/desorption, precipitation/dissolution, and redox processes. Natural min-eral and organic sorbents present in soils have a strong influence on heavy metals sorption. As these sorbents are usually negatively charged, they attract heavy metals cations through electrostatic force.

Interfacial Characteristics of WC Particles Reinforced Hadfield Steel Matrix Composites

2010 ◽  
Vol 654-656 ◽  
pp. 2708-2711
Author(s):  
Guo Shang Zhang ◽  
Yi Min Gao ◽  
Jian Dong Xing ◽  
Shi Zhong Wei ◽  
Ji Wen Li ◽  
...  
Keyword(s):  
Interface Layer ◽  
Diffusion Reaction ◽  
Hadfield Steel ◽  
Shell Shape ◽  
Steel Matrix ◽  
Matrix Composites ◽  
Forming Mechanism ◽  
Constituent Phase ◽  
Two Phases ◽  
New Phase

In order to improve the wear resistant properties, WC ceramic particles were used to reinforce Hadfield steel. WCp/Hadfield steel composites were fabricated by optimized solid state sintering process of powder metallurgy. Interface structure, constituent phase and the forming mechanism of the composites were investigated systematically. The results show that the WCp/Hadfield steel composites have uniformly distributed particles and well bonded interface between WC particles and Hadfield steel. In the WCp/Hadfield steel composites, the interface between WC particles and Hadfield steel matrix is of shell shape, in which W, Fe and Mn elements diffuse between the two phases. The interface is of metallurgical bond, in which a new phase, namely Fe3W3C is formed. The micro-hardness of the interface layer is between those of WC and the steel matrix, which can provide a guarantee for the property transition between WC particles and Hadfield steel matrix. The diffusion reaction mechanism of the interface was also systematically studied.

Existence of a new phase in barium carbonate-barium sulphate system

1982 ◽  
Vol 47 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Bohumil Hájek ◽  
Jan Ondráček ◽  
Alexander Muck
Keyword(s):  
Barium Carbonate ◽  
Microscopic Analysis ◽  
Barium Sulphate ◽  
Lower Content ◽  
X Ray Diffraction ◽  
X Ray ◽  
Analysis Techniques ◽  
Dilute Aqueous Solutions ◽  
Two Phases ◽  
New Phase

The infrared spectroscopy, X-ray diffraction, TGA and DTA, and microscopic analysis techniques were applied to a study of BaCO3-BaSO4 systems, performed on samples prepared by precipitation from dilute aqueous solutions. A new BaCO3. 3 BaSO4 phase was established in the system with the BaSO4 structure exhibiting parallel extinction (replacement of the SO42- anion by a CO32- anion, the d values are equal). The BaCO3-BaCO3. 3 BaSO4 region contains a mixture of the two phases, the latter phase, however, may be oversaturated by carbonate. In the BaCO3. 3 BaSO4-BaSO4 region, unstable phases are formed with a lower content of carbonate.

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