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Упит dcterms_subject_txt:drilling fluid formulation

210 items

  • Laboratory Testing of Nanosilica- Reinforced Silicate and Polyacrylamide Gels

    Irina Zahirovic, Dušan Danilović, Milica Šuput Vranjin, Miloš Tripković (2023)
    drilling fluid formulation, upstream oil and gas, fluid dynamics, fluid loss control, gel

  • Numerical modeling of Selanac debris flow propagation using SPH code

    Jelka Krušić, Biljana Abolmasov, Miloš Marjanović, Manuel Pastor, Saeid M. Tayyebi (2021)
    The Selanac debris flow is a very huge event triggered after extreme rainfall caused by Cyclone Tamara activity in the Republic of Serbia in May 2014. The Selanac case study was already modelling in different programs using Voellmy rheology assumptions like RAMMS software. In this paper research are focusing particularly on the process of debris flowing from initiation zone to main deposition area using Geoflow SPH two-phase model considering frictional rheology law. Main rheological parameters are back-calculated using also ...
    debris flow, modelling, SPH code, DEM
    ... Journal of Fluid Mechanics 199 (1): 177-215. Takahashi, T. (2007). ‘’Debris Flow: Mechanics, Prediction and Countermeasures’’. Annual Review of Fluid Mechanics 13 (1): 57-77. Zienkiewicz, O.C., Shiomi, T. (1984). ‘’Dynamic behavior of saturated porous media; The generalized Biot formulation and its ...
    ... found very suitable in different parts of fluid mechanics. Its main difference from other most used methods like finite element and finite difference methods, is in absence of numerical grid, and while mass is presented with particles of solid and fluid phase. Each particle has information about ...
    ... Debris flows occur usually after saturated, mainly poorly sorted material, started to flow down the slope as a result of motion of solid and fluid phase. Different mechanisms, rheological and numerical models are used in this area of research. Generally, there are mainly two groups of models ...

  • Overcoming the Low Oral Bioavailability of Deuterated Pyrazoloquinolinone Ligand DK-I-60-3 by Nanonization: A Knowledge-Based Approach

    Jelena R. Mitrović , Branka Divović-Matović, Daniel E. Knutson, Jelena B. Ðoković, Aleksandar Kremenović, Vladimir D. Dobričić, Danijela V. Randjelović, Ivana Pantelić, James M. Cook, Miroslav M. Savić, Snežana D. Savić (2021)
    Poor water solubility of new chemical entities is considered as one of the main obstacles in drug development, as it usually leads to low bioavailability after administration. To overcome these problems, the selection of the appropriate formulation technology needs to be based on the physicochemical properties of the drug and introduced in the early stages of drug research. One example of the new potential drug substance with poor solubility is DK-I-60-3, deuterated pyrazoloquinolinone, designed for the treatment of various neuropsychiatric ...
    pyrazoloquinolinones, nanocrystals, wet media milling, fasted/fed bioavailability
    ... 2 of 19 investigation, the role of the formulation scientist becomes crucial to implement advanced formulation strategies early in development processes [2]. However, many attempts under- achieve to overcome poor solubility due to the selection of formulation strategy driven by researchers’ experience ...
    ... select a formulation strategy based on physicochemical properties of DK-I-60-3 in order to enhance bioavailability after oral administration. As a first step, preformulation studies were designed to obtain insight into the key properties of DK-I-60-3, which would guide further stages of formulation devel- ...
    ... conducted after oral administration of nanocrystal formulation F5 and corresponding coarse suspension with the same qualitative and quan- titative content (S5) in fasted and fed state. In fasted group, food intake was restricted 10 h before and 4 h after formulation administration, while water was provided ad ...

  • Freeze-dried nanocrystal dispersion of novel deuterated pyrazoloquinolinone ligand (DK-I-56-1): Process parameters and lyoprotectant selection through the stability study

    Jelena R. Mitrović, Maja Bjelošević Žiberna, Aleksandar Vukadinović, Daniel E. Knutson, Dishary Sharmin, Aleksandar Kremenović, Pegi Ahlin Grabnar, Odon Planinšek, Dominique Lunter, James M. Cook, Miroslav M. Savić, Snežana D. Savić (2023)
    Recently, nanocrystal dispersions have been considered as a promising formulation strategy to improve the bioavailability of the deuterated pyrazoloquinolinone ligand DK-I-56-1 (7‑methoxy-2-(4‑methoxy-d3-phenyl)-2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one). In the current study, the freeze-drying process (formulation and process parameters) was investigated to improve the storage stability of the previously developed formulation. Different combinations of lyoprotectant (sucrose or trehalose) and bulking agent (mannitol) were varied while formulations were freeze-dried under two conditions (primary drying at -10 or -45 °C). The obtained lyophilizates were characterized in terms ...
    Pharmaceutical Science
    ... promising formulation strategy to improve the Pyrazoloquinolinone bioavailability of the deuterated pyrazoloquinolinone ligand DK-I-56-1 (7-methoxy-2-(4-methoxy-d3-phenyl)- Nanocry“?ls 2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one). In the current study, the freeze-drying process (formulation and Š:ŽŽŽŽng ...
    ... undissolved particles would not contribute significantly to the tonicity of the formulation. Therefore, the concen- tration of lyoprotectants and bulking agent was initially adjusted to achieve the isotonic formulation. Nanosuspensions were freeze-dried by the lyophilization-1 and the results of ...
    ... The conditions for primary drying also depend on this parameter. In this lyophilization phase, the temperature of the formulation should be kept below the critical formulation temperature (CFT). At this temperature, the internal morphology of the product begins to change, resulting in significant ...

  • Curcumin nanonization using an alternative small-scale production unit: selection of proper stabilizer applying basic physicochemical consideration and biological activity assessment of nanocrystals

    Ines Nikolić, Jelena Antić-Stanković, Dragana Božić, Danijela Ranđelović, Bojan Marković, Dominique Jasmin Lunter, Aleksandar Kremenović, Miroslav Savić, Snežana Savić (2020)
    As the number of poorly soluble drugs is increasing, nanocrystals have become very interesting due to wide range of application possibilities. Curcumin was used as a model active ingredient in this work. Even though it has many proven positive effects, due to its physicochemical issues, its possibilities have not been fully exploited. The goal of this work was to select optimal conditions for a top-down method for curcumin nanosuspension production, and to perform their comprehensive characterization applying complementary methodologies: ...
    nanocrystal, curcumin, top-down method, wetball milling

  • Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention

    Milica Ješić, Bojan Martinović, Stefan Stančić, Miroslav Crnogorac, Dušan Danilović (2023)
    Gas wells, particularly those situated onshore, play a vital role in the global energy sector by supplying a significant portion of natural gas. However, operational challenges, notably gas hydrate formation, pose substantial issues, leading to complications such as flowline blockages and unexpected well shutdowns. Gas hydrates, crystalline structures resembling ice, ...
    Gas Well, Gas Hydrate Formation, Well Modeling, Well Performance Optimization, Choke Position Adjustments, Methanol Injection

  • Constitutive Model for Analysis of Long-Term Municipal Solid Waste Landfill Settlement

    Irena Basarić Ikodinović, Dragoslav Rakić, Mirjana Vukićević, Sanja Jocković, Jovana Janković Pantić (2022)
    Large long-term settlement occurs at the municipal solid waste landfills over an extended period of time which may lead to breakage of the geomembrane, damage of the cover systems, other protective systems or facilities constructed on top of a landfill. Also, municipal solid waste is an extremely heterogeneous material and its properties vary over location and time within a landfill. These material characteristics require the formulation of a new constitutive model to predict the long-term settlement of municipal solid ...
    constitutive model, finite element analysis, municipal solid waste, settlement

  • Softverski alati za korišćenje resursa za srpski jezik

    Ivan Obradović, Ranka Stanković (2008)
    ... for web search engines. Thus the “working” ac- ronym of this web application – WS4QE (Work- station for Query Expansion). The problem of query formulation stems from the fact that the use formulating the query is most often interested in documents related to a spe- cific concept, the way concepts ...
    ... such as electronic diction- aries and wordnets offer possibilities for a more systematical solving of the outlined problems related to query formulation. In this task, it is important to offer the user the greatest possible flexibility in the choice of strings to be used for formulating the final ...
    ... cally, semantically, but also to another language (English). Besides, WS4QE provides further possibilities for the user to control the query formulation, since in addition to expansion, it also offers a narrowing of the query. SOFTWARE TOOLS FOR SERBIAN LEXICAL RESOURCES 54a Morphological expansion ...

  • Значај петрографске анализе флуидних инклузија

    Стефан Петровић, Милош Велојић (2022)
    У раду је истакнут значај петрографске анализе током истраживања флуидних инклузија и приказане могућности ове методе на примерима неких од карактеристичних петрографских појава из различитих минерала. Петрографска анализа је први корак у испитивању флуидних инклузија. Правилно спроведена, петрографска анализа омогућава одређивање генетске везе флуидних инклузија и минерала домаћина, препознавање карактеристика флуидних инклузија и релевантну интерпретацију података из наредних корака истраживања. Петрографском анализом се дефинишу: а) дистрибуција флуидних инклузија у минералу; б) облик, величина и фазни састав флуидних инклузија; в) групације ...
    петрографија, флуидне инклузије, флуиди, групације

  • An Integrated Environment for Management and Exploitation of Linguistic Resources

    Ranka Stanković, Ivan Obradović (2009)
    ... demonstrating the pos- sibilities our integrated environment offers in different areas of application. A. Web search The problems in query formulation stem from the fact that the user formulating a query is most often interested in documents related to a specific concept, in the sense con- ...
    ... such as electronic dictionaries and wordnets offer possibilities for a more systematic solving of the outlined problems related to query formulation. In order to obtain a balance between recall and precision, it is impor- tant to provide the user with the greatest possible flexibility in ...
    ... expand the query morphologically, semanti- cally, but also to another language (English). Besides, the user can further fine-tune query formulation, since in addi- tion to being expanded, the query can also be narrowed. Morphological expansion is based on the use of morpho- logical dictionaries ...

  • Fluid Evolution of the Čukaru Peki Cu-Au Porphyry System (East Serbia) inferred from a fluid inclusion study

    Velojić Miloš, Jelenković Rade, Cvetković Vladica (2020)
    Borska metalogenetska zona, Timočki magmatski kompleks, fluidne inkluzije, porfirska ležišta bakra, masivni sulfidi, slani rastvori, ključanje fluida

  • Uticaj utiskivanja gas-lift gasa na prenos mase i toplote

    Branko Grubač (2019)
    Nakon uvođenja kontinualnog gas-lifta, primećen je porast proizvodnje tečnog naftnog gasa, TNG, u postrojenju za preradu gasa, kao jednog od finalnih proizvoda dobijenog iz fluida gaso kondenzatnih i rastvorenog gasa iz naftnih bušotina. Pretpostavljeno je da se prisustvom gas-lift gasa uspostavlja drugačija ravnoteža faza u odnosu na slučaj bez gaslifta, te da je gas-lift gas stripovao propan i butane iz tečne u parnu fazu, što je dovelo do povećanja prinosa TNG-a. Napravljen je model bušotine koja radi u kontinualnom gas-liftu ...
    gas-lift, modelovanje bušotine, prenos mase i toplote, taloženje parafina
    ... Sastav parne faze fluida – Poređenje Slučaja #1 i Slučaja #2 Komponenta Bušotina B-1 Bušotina B-2 Bušotina B-3 Slučaj #1 Slučaj #2 Slučaj #1 Slučaj #2 Slučaj #1 Slučaj #2 Fluid sa GL gasom Fluid bez GL gasa Fluid sa GL gasom Fluid bez GL gasa Fluid sa GL gasom Fluid bez GL gasa ...
    ... proračun razmene toplote fluida u bušotini koja proizvodi u kontinualnom gas-liftu. Proračun razmene toplote obuhvata razmenu toplote između fluida u kezingu (gas-lift gasa) i okoline (zemlje), zatim i razmenu toplote između fluida u tubingu (ležišni fluid) i fluida u kezingu. Na razmenu toplote ...
    ... ovako opisanom termodinamičkom sistemu, pored pritiska i temperature, utiču i osobine fluida kao što su toplotni kapacitet, sastav fluida, režim strujanja, količina fluida, brzina kretanja fluida, smer kretanja fluida, ali i sama kompozicija bušotine odnosno materijal tubinga, kezinga, hrapavost cevi ...

  • Analiza softvera za projektovanje ESP sistema

    Aleksandar Sredojević (2024)
    U momentu kada pritisak na dnu bušotine nije dovoljan da savlada ukupne gubitke pritisaka od dna bušotine do separatora, proizvodnja pomoću ležišne energije nije više moguća i bušotina prestaje sa eruptivnim radom. Kako bi ponovo omogućili proizvodnju fluida iz bušotine, potrebno je primeniti neke od mehaničkih metoda eksploatacije. Najprimenljivije mehaničke metode eksploatacije su: gas lift (GL), dubinske pumpe sa klipnim šipkama (SRP), električne uronjene centrifugalne pumpe (ESP), zavojne pumpe (PCP) i hidraulične pumpe (HP). Jadna od tih metoda koja ...
    električna centrifugalna pumpa (ESP), proizvodnja fluida, mehaničke metode eksploatacije, Prosper, Pipesim
    ... koji je primenio glavni pokretač na pumpi predaje lopaticama radnog kola koje dalje predaju energiju fluidu, gde se povećava brzina kretanja fluida i tako sama kinetička energija fluida. Fluid velike brzine strujanja koji se ispušta pod uglom od horizontale zatim ulazi u lopatične kanale difuzora ...
    ... regulisana opštom energetskom Jednačinom koja opisuje očuvanje energije između dve tačke u fluidu koji teče. Ovo navodi da je promena energije u sadržaju fluida je jednak radu obavljenom na fluid. Fluid koji teče u pumpi može imati tri oblika energije: potencijalnu, kinetičku i pritisnu energiju ...
    ... datog protoka fluida, plus svi gubitaka energije koji se javljaju u pumpi. Korisna hidraulična snaga je proporcionalna proizvodu napora, protoka fluida i specifične težine fluida i može se izračunati iz H- Q krive pumpe pri bilo kojoj tački tečenja. U dve tačke Je nula: pri protoku fluida od nule ...

  • Развој модела конструкције просторија отварања рудника са подземном експлоатацијом

    Dražana M. Tošić (2016-08-26)
    Приликом израде подземних просторија у стјенској маси долази до нарушавања природне равнотеже напонских стања стијенског масива који су владали прије израде тих просторија, при чему долази до појаве прертасподјеле напона и његове концентрације у појединим правцима и тачкама, односно долази до појаве пластичних деформација које су праћене ломљењем стијенске масе и кретањима материјала према откопаном простору...
    модел, метод коначних елемената, просторија отварања, напон, дефеормација стијенског масива, алгоритам функционалних зависности

  • Fluid inclusion study in quartz of the Rudnik Pb-Zn-Cu-Ag skarn deposit, Serbia

    Stefan Petrović, Ronald J. Bakker, Vladica Cvetković, Rade Jelenković (2023)
    Six types of fluid inclusions were identified in three growth zones of hydrothermal quartz from the Rudnik skarn deposit. In the core zone, primary two-phase fluid inclusions of high (type 1) and moderate salinity (type 2) homogenized to liquid between 350-430 °C and 340-420 °C, respectively. Raman analysis revealed that the vapour phases are a CO2-CH4 gas mixture, with a predominance of CO2. The core contains and dispersed vapour-rich fluid inclusions of low salinity (type 3) composed of CO2-CH4-H2S ...

  • Fluid inclusion systematics in the Okoška gora polymetallic deposit

    Aleš Šoster, Miloš Velojić, Barbara Potočnik Krajnc, Matej Dolenec (2021)
    ... Измењено: 2023-10-14 04:27:31 Fluid inclusion systematics in the Okoška gora polymetallic deposit Aleš Šoster, Miloš Velojić, Barbara Potočnik Krajnc, Matej Dolenec Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Fluid inclusion systematics in the Okoška ...
    ... veins of transparentquartz intersectvi amethyst (Janez Žavašnik, verbal comm.), suggesting the later's earlier paragenetic p Fluid inclusion systematics A total of 100 fluid inclusions in sphalerite and quartz from five samples of ore were investigated in this study. Both types of quartz form well ...
    ... between pre-existi and gangue minerals. Sphalerite is honey yellow or dark brown in color and its transparency makesit suitable for fluid inclusion analysis. The fluid inclusions are usually 10-50 umin size, All of the analyzed inclusion liquid-rich and contain about 60—80 % liquid and 20-40 % vapourphase ...

  • Convective heat transfer in centrifugal pumps lifted wells: the case of South-Eastern Europe waxy wells

    Bojan Martinovic, Marija Živković, Branko Grubač (2021)
    Electric submersible pumps (ESP) are applied in wells where additional energy is needed to ensure discharge of the fluid to the surface through the tubing. At the discharge side of the pump the fluid has bigger velocity, thus the pump induces a forced convection between the fluid and the tubing inner surface. Understanding of convective heat transfer in wellbores and analyses of influential parameters provides a possibility to optimise value of convective heat transfer coefficient in order to avoid ...
    prenos toplote konvekcijom, ESP pumpa, svojstva fluida, problemi u radu bušotine

  • Hibridni sistem za planiranje i analizu ventilacije rudnika

    Nikola Lilić, Ranka Stanković, Ivan Obradović (2000)
    Ventilacija rudnika, informacioni sistemi
    ... neviskoznog fluida. Ovim se potvrđuje Prantlova (Prandtl) ideja po kojoj fluid struji van graničnog sloja upravo kao da je savršen. Razume se, to ne znači da realan fluid postaje neviskozan već znači da se ova konstatacija odnosi na kinematičku sliku strujanja, jer svojstva realnog fluida kao što su: ...
    ... softvera NISA/3D – FLUID NISA/3D–FLUID (Numerički Integrisani elementi za Analizu 3D Sistema mehanike Fluida) je program konačnih elemenata razvijen i podržavan od EMRC (Engineering Mechanics Research Corporation) za analizu širokog spektra problema koji postoje u mehanici fluida. Pretprocesiranje ...
    ... primenjenu mehaniku, teoriju aproksimacija, numeričku analizu i računarsku nauku. Računska dinamika fluida (Computational Fluid Dynamics - CFD) omogućava analizu sistema koja se odnosi na procese strujanja fluida i prenosa toplote, a takođe, i uključivanje pojava kao što su na primer hemijske reakcije. CFD ...

  • Design of a sucker rod pumping system

    Ana Ponoćko (2024)
    For a long time in the history of oil production, sucker rod pumps have been the first and in many cases the only choice when it comes to mechanical extraction methods. Proper selection of each individual element of the system enables optimization, which entails benefits in the form of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The ...
    sucker rod pump, fluid production, mechanical extraction methods,, Prosper, QROD, RODSTAR
    ... change caused by the fluid inside the pump depends on the 8 compressibility of the fluid mixture inside the cylinder. If the fluid is nearly incompressible, very small volume changes due to the small movement of the plunger cause large pressure changes. In cases where the fluid is more compressible ...
    ... converts mechanical work into potential energy to increase the pressure of the fluid. The pressure at which the fluid enters the pump from the reservoir is called the suction pressure, while the pressure at which the fluid exits the pump is referred to as the discharge pressure. The difference between ...
    ... strings, tubing, and the weight of the fluid. 3. Elastic Force: Due to the elasticity of the rod strings and the weight of the fluid. 4. Inertial Forces: Resulting from the movement of the mass of the rod strings, pump plunger, and the weight of the fluid. 5. Frictional Forces: Including: ...

  • Optimizacija ispirnih fluida za bušenje dirigovanih bušotina

    Vukoman Krgović (1994)
    Ispirni fluidi, dirigovano bušenje