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Drilling muds play an important role in drilling and production operations so that the degree of success in such operations is determined by the proper design of these fluids. To optimize drilling operations and avoid excessive expenditure, it is essential to prepare a drilling mud that is both cheap and efficient. Fluid additives are typically used in drilling systems to improve these fluids' capabilities in terms of hole cleaning capacity, filtration control, viscosity, yield point, heat transfer, etc. However, environmental concerns, cost of production, and availability are always considered challenging factors. This study introduces an eco-friendly herbal fiber in powder and regular forms as a potential alternative to other chemical additives. To do so, Alyssum homolocarpum seed mucilage was added with different concentrations to the water-based drilling muds, and its rheological behavior, filtration control, and the induced formation damage were examined and the optimum concentration was introduced. The results of this study revealed the advantages of the drilling muds formulated with Alyssum in terms of filtration control, rheology, formation damage, and greenness.

In this study, the flow and heat transfer characteristics of the forced pulsating Al2O3-water nanofluid were numerically studied. The pulsating excitation of the nanofluid is provided by the Helmhertz self-excited oscillating cavity. The large eddy simulation method is used to solve the equation, and the local Nusselt number and heat transfer performance index are used to analyze the heat transfer characteristics of the nanofluid in the self-excited oscillation heat exchange tube. In addition, the effect of different downstream tube diameters on heat transfer enhancement is discussed. The research results show that the existence of the countercurrent vortex can increase the disturbance of the near-wall fluid, thereby improving the mixing degree of the near-wall fluid and the central mainstream. As the countercurrent vortex migrates downstream, pulse enhanced heat transfer is realized. Furthermore, it was also found that when the downstream tube diameter d2 = 1.8d1, the periodic effect of the local Nusselt number of the wall is the best and the heat transfer performance index has the most stable pulsation effect within a pulsation cycle. But when d2 = 2.0d1, the change curve of heat transfer performance index in a pulsating period is the highest, the maximum value is 3.95.

High-pressure injection injuries with paint have long been heralded as a condition requiring timely and aggressive debridement with relatively poor functional outcomes and a significant proportion of patients progressing to require amputation of the involved digit or limb. Catheter irrigation is regularly used in the treatment of common hand infections and wounds. However, this has not been described for the treatment of paint injection injuries. We describe a case of a young painter who sustained an accidental water-based paint injection injury and was successfully treated with minimally invasive surgical debridement augmented by the use of catheter irrigation, despite a delayed presentation. The patient had regained full function of his hand by four months from the index presentation and returned to work. We illustrate how not all high-pressure injection injuries require an extensive incision and that catheter irrigation can be a significant tool to augment a minimally invasive approach.

AIM AND OBJECTIVE The objective of this study was to monitor the pH stability over a period of 6 months of two-bottle self-etching (SE) primers. MATERIALS AND METHODS Four commercially available two-bottle SE primer solutions, Adhese SE (Ivoclar Vivadent; Schaan, Liechtenstein), Clearfil SE (Kuraray; Tokyo, Japan), Contax Primer (DMG; Hamburg, Germany), and Enabond SE (Micerium; Avegno (Ge), Italy), containing water as the main solvent were selected. The pH values during a 6-month storage period at intermittent temperature were daily measured by means of a microprocessor-based pH/temperature meter and hence recorded, tabulated, and analyzed. RESULTS The mean values of overall pH measurements and standard deviation for Adhese SE, Clearfil SE, Contax Primer, and Enabond SE are, respectively, 1.70 (±0.01), 1.72 (±0.01), 1.20 (±0.01), 1.80 (±0.01). One-way ANOVA did not detect any significant change of the mean pH values of all measurements over time. CONCLUSION The conventional 6-months storage did not affect the pH values of the water-containing primers of two-bottle SE adhesives. CLINICAL SIGNIFICANCE This study provides evidence that conventional storage under adequate conditions did not affect the pH values of the water-containing primers of two-bottle SE adhesives with different monomer formulations. Clinicians may rely on the known pH value of the selected SE adhesive during shelf-life.

Background Individuals who participate in outdoor sports are subject to an increased risk of developing skin cancer. To date, there has been no review examining skin cancer and sun protective behaviours specific to outdoor, water based sports. Therefore, this scoping reviews objectives were to (1) summarise volume and type of scientific literature available relating to skin cancer, (2) examine current sun protective behaviours and (3) identify knowledge gaps to inform future research. Method A scoping review was conducted to address the objectives following the PRISMA guidelines. Seven databases were searched; identified studies were screened based on title, abstract and full-text for outdoor water based sports which examined skin cancer and/or sun protective behaviours. Data was extracted, synthesised and critically appraised using a modified AXIS tool. Percentage frequencies were calculated, and key results were placed in tabular or graphical presentation. Results Nine cross sectional studies were identified, all defined as low level evidence. A combined sample of 4,377 participants across six countries and five water based sports showed BCC (71%) was the most common skin cancer, followed by melanoma (18%) and SCC (10%). The head (41%) and upper-limbs (27%) were the most common location. Conclusion This review highlights the minimal research available and demonstrates those in water based sports are at high risk of developing skin cancer. Due to difficulty adhering to sun protective behaviours, the most prevalent location is the upper body. Included studies were of low level evidence, providing opportunity for future research to expand upon the gaps in the current literature.

Many drilling problems are encountered continuously while drilling oil wells in the southern Iraqi oil fields. Many of these problems are ineffectively handled resulting in a longer non-productive time. This study aims to identify the formations such as Dammam, and Hartha formations،diagnose potential problems and provide the solution for lost circulation problem. After conducting a comprehensive study on the subject and based on available data, previous studies and some information, the managed pressure drilling (MPD) method was the best technique to solve this problem. This process may use various techniques including control of back pressures .Thus, reducing the risk and control the costs of drilled wells, which have narrow pressure window by managing the wellbore pressure profile. The well plan software program provided by Halliburton Company was used, this software is based on a database and data structure common to many of Landmark’s drilling applications. Mud used with various injection rates to choose the rate that provides the conditions to achieve the best drilling process, as it using mud weights of (8.8 -8.7 ) ppg and applied a surface back pressure (50 psi). Depending on specifications of second hole the optimal injection rate was chosen using the (hydraulics) program. As a results, rate of water injection (850) gpm, is the best which it provides a good efficient cutting transport ratio (CTR), which means high stability and preventing formation damage in addition to controlling in mud losses

Background: Most available therapeutics to address alopecia are based on singular targets and mechanism of action based on the assumption of sub-classification to reflect morphological or etiological sub-classes such as hereditary vs acquired factors, anti-inflammatory vs. non-inflammatory factors or scarring vs. nonscarring factors. Aims and Objective: Impact of oral consumption of Diabliss Hair Water, a multi-component herbal water supplement (HWS) on hair fall reduction, hair growth, hair density, hair thickness was investigated in a single arm, exploratory, pilot open label clinical study among healthy male and female subjects of age group between 35-50 years, with hair fall and hair thinning concerns. Materials and Methods: The study was conducted under dermatological control and included hair fall by comb test, hair pull test, hair thinning measurement using photo numerical scale (modified Norwood and Ludwig scale) and assessment for hair quality along with the phototrichogram assessment using Trichoscan® with Cutiscope. Results: The Diabliss HWS was efficacious in improving hair growth rate and density as per TrichoScan® assessment, improvement in hair thickness as per Caslite-Nova software. The Diabliss HWS was also efficacious in improving the hair tensile strength (break force by Chatillon Force gauge), reducing hair fall and improving the hair quality. By the end of the study the Diabliss HWS was found to show an improvement in the entire study population in all of the assessments parameters. Dermatologist assessment parameters of hair texture and hair shine also showed improvements in the entire study population. Conclusion: The Diabliss HWS was found to be efficacious in providing hair fall control and hair growth benefits as per the dermatological and instrumental evaluations using TrichoScan®. The product was well tolerated with no product related AE or SAE with regular consumption for 06 months. Keywords: Herbal Supplement, Hair C

Colon Cancer is the fourth most common form of cancer and the second-leading cause of cancer related deaths in the United States. A large part of the reason the number of fatalities is so high is late detection as when detected in the early stages of development 9 out of 10 cases of colon cancer are non-fatal 5 years after detection. Currently the main method of colon cancer detection are colonoscopies which are highly invasive and time intensive procedures. In this work we propose a new diagnostic technique for colon cancer using an InSb based device that works by a change in the spectral response of the metamaterial when exposed to electromagnetic waves in the terahertz regime and combined with cancerous colon tissue as compared to the response when combined with healthy colon tissue. We attribute this change in spectral response is due to the differing optical properties of the healthy and cancerous colon tissue as well as the creation of surface plasmon polaritons within our device.

A linear stability analysis is performed for the onset of Marangoni convection in a horizontal layer of a nanofluid heated from below and affected by rotation. The top boundary of the layer is assumed to be impenetrable to nanoparticles with their distribution being determined from a conservation condition while the bottom boundary is assumed to be a rigid surface with fixed temperature. The motion of the nanoparticles is characterized by the effects of thermophoresis and Brownian diffusion. A modification model is used in which the effects of Brownian diffusion and thermophoresis are taken into consideration by new expressions in the nanoparticle mass flux. Also, material properties of the nanofluid are modelled by non-constant constitutive expressions depending on nanoparticle volume fraction. The steady-state solution is shown to be well approximated by an exponential distribution of the nanoparticle volume fraction. The Chebyshev-Tau method is used to obtain the critical thermal and nanoparticle Marangoni numbers. Different stability boundaries are obtained using the modified model and the rotation.

The current research demonstrates the revolving flow of water-based Fe3O4 nanofluid due to the uniform rotation of the disc. This flow of nanofluid is investigated using CFD Module in COMSOL Multiphysics. However, the similarity solution for this flow is also obtained after transforming the given equation into a non-dimensional form. In the CFD Module, streamlines and surface plots are compared with the similarity solution for the magnitude of the velocity, radial velocity, tangential velocity, and axial velocity. The results from the direct simulation in the CFD Module and the solution of dimensionless equations represent a similar solution of velocity distribution. The derived results show that increasing the volume concentration of nanoparticles and effective magnetic parameters decrease the velocity distribution in the flow. Results in the CFD Module are important for monitoring the real-time particle tracing in the flow and, on the other hand, the dimensionless solution is also significant for the physical interpretation of the problem. Both methods of solution empower each other and present the physical model without sacrificing the relevant physical phenomena.

Made available in DSpace on 2022-04-28T19:43:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Background: Resistance training has proven to be an excellent method for counteracting aging physical dysfunctions. However, its application in the liquid environment is not yet fully elucidated. Aim: To investigate the effects of water-based resistance training (WBRT) with the concentric phase performed as fast as possible, compared to conventional resistance training (CRT), on physical functional capacity, muscle strength, and body composition in older women. Methods: Thirteen healthy older women participated in the WBRT and 11 in the CRT. Estimation statistics focused on the effect size of the experiment/intervention were used. We also analyzed the intervention effect based on the percentage delta between WBRT and CRT. Results: The WBRT group showed a negative large effect (d = − 0.922; p = 0.0274) for the timed up and go, and a large effect for chair rise in 30″ and the elbow flex test (d = 1.58; p = 0.0012; d = 2.8; p = 0.01) respectively. Intervention comparisons based on the delta percentage between WBRT and CRT presented an intermediate effect (d = 0.606; p = 0.157) for the stair climb, a large effect (d = 0.988; p = 0.0282) for the timed up and go, and a large negative effect [d = − 1.32 (90.0% CI − 1.92, − 0.646); p = 0.0038] for the elbow flex test. Concentric extensor-flexor peak torque (60°/s) showed an intermediate effect (d = 0.749; p = 0.0876; d = 0.65; p = 0.122 respectively). Body fat (%) demonstrated an intermediate effect (d = 0.523; p = 0.234). Conclusion: WBRT with the concentric phase performed as fast as possible was able to improve physical functional capacity and maximal knee extension strength of older women. Laboratório de Estudo do Desempenho Humano Universidade Federal do Amazonas, Av. Gen. Rodrigo Otávio. 5614, Coroado Programa de Pós Graduação Stricto Sensu em Ciências do Movimento Humano Faculdade de Educação Física e Fisioterapia Universidade Federal do Amazonas Projeto de Extensão Universidade Aberta da Terceira Idade Universidade Federal do Amazonas Centro de Estudo e Laboratório de Avaliação e Prescrição de Atividade Motora Universidade Estadual Paulista Centro de Estudo e Laboratório de Avaliação e Prescrição de Atividade Motora Universidade Estadual Paulista

This paper aims at assessing the use of nanomaterials in painting conservation and in cleaning practices that could be alternative to the traditional ones to overcome the limits of new green materials. Titanium dioxide nanoparticles have been spread and studied on historical painting surfaces with good results. In particular, the properties of TiO2 nanoparticles have been considered useful for self-cleaning and protective purposes against the accumulation of dirt and dust that represents the first phase in deterioration of historical painting surfaces. TiO2 nanoparticles, prepared in distilled water by Pulsed Laser Ablation in Liquids, were applied on painting mock-ups realized in the laboratory according to old recipes and using historical binders and pigments. The surface characteristics of the painting were investigated by contact angle measurement and by Atomic Force Microscopy. The optical and aesthetical compatibility of the colloidal dispersions with the painting was assessed by spectrophotometry, and then the cleaning efficiency was evaluated by discoloration of a dye under ultraviolet irradiation, at fixed time intervals, using colorimetric technique. Because of the high reactivity of nanoparticles, the possibility of degrading the painting surface, together with the chromatic marker, was examined by colorimetric measurements. The evaluation of the color changes is important for all the materials belonging to cultural heritage, especially painting, for which the color modification induced by protective and/or cleaning interventions could irremediably compromise the work of art.

It is repeatedly proved that the application of the radiant heating system is cost-effective. The most energy-efficient solution is the use of gas infrared emitters. In this case, there is no intermediate heating medium, and the heat of combustion of the gas enters the premises. However, this solution has a number of restrictions on the availability of natural gas, comfort, and fire hazard. Also, a highly efficient solution is the use of water infrared emitters, which can be radiant panels or radiant profiles that use an intermediate heating medium but do not have many of the limitations inherent in gas systems. A common problem for all types of radiant heating is the lack of a scientifically grounded and generally accepted engineering methodology for its design. Most of the regulatory documents simply do not take into account the peculiarities of the operation of radiant heating systems and, thus, do not allow a number of its advantages to be realized. This research was carried out based on NNGASU Radiant Heating Laboratory, unique in Russia, and is devoted to the peculiarities of the formation of the temperature regime in the premises heated by water infrared emitters, as well as the thermal regime of external enclosing structures in these premises.

In recent times, with the advent of exploSration activities in deeper hydrocarbon reserves, drilling of wells in HPHT conditions is one of the most studied field in the upstream oil and gas industry. Water-based fluids are the most common and frequently used drilling fluids oil and gas well construction. Although, water-based drilling fluids are environment friendly and relatively in-expensive, it is often associated with many problems when used in HPHT conditions. In order to overcome these problems in such viable conditions, modified surfactants are used with the mud to counteract the problems associated with it. This paper discusses the different applications of anionic and non-ionic surfactants in water-based drilling fluids both in laboratory and field scales. The paper also discusses the mechanisms of the surfactants and the effect on various mud properties to overcome hole problems like wellbore instability, rheology and filtration loss, foaming and flocculation of mud.

In the majority of rechargeable batteries including lithium‐ion batteries, polyvinylidene fluoride (PVdF) binders are the most commonly used binder for both anode and cathode. However, using PVdF binder requires the organic solvent of N‐methyl‐2‐pyrrolidone which is expensive, volatile, combustible, toxic, and has poor recyclability. Therefore, switching to aqueous electrode processing routes with non‐toxic binders would provide a great leap forward towards the realization of ideally fully sustainable and environmentally friendly electrochemical energy storage devices. Various water‐soluble binders (aqueous binders) were characterized and compared to the performance of conventional PVdF. Our study demonstrates that the electrochemical performance of Zn/MnO2 aqueous batteries is significantly improved by using sodium carboxymethyl cellulose (CMC) binder. In addition, CMC binders offer desirable adhesion, good wettability, homogeneous material distribution, and strong chemical stability at certain pH levels (3.5–5) without any decomposition for long‐cycle life.

Simulation of Computational Fluid Dynamic is applied to present the thermal performance of water-based Yttrium oxide nanofluid in subchannel of pressurized water reactor (PWR) system. Thermal hydraulic aspect such as pressure drop and heat transfer are estimated in typical conditions of pressurized water with flow rates ranged (20×103≤Re≤80×103) using fresh water (0 %vol.) and different volume fraction of water-Yttrium oxide nanofluid (2 and 4% vol.) as coolant fluid. Results were obtained and compared with correlations of single-phase pressure drop and convective heat transfer for the case of fully developed turbulent flow. The addition of Yttrium oxide nanoparticles to the coolant fluid in pressurized water reactor led to increase in convective heat transfer coefficient and pressure drop. Increasing the nanoparticle volume fraction of (2 and 4% vol.) causing an increase in the average Nu by 3.46% and 7.61%, respectively. The CFD model established in ANSYS software was validated by comparing the pressure drop of CFD results with Blasius correlation and Nu with Ma¨ıga et al. correlation and gave a good agreement.

In this contribution, the investigation conducted on alternative fuels includes methanol 20% blended with gasoline 80% and emulsion-based fuel with the composition of gasoline 80%, ethanol 15%, and H2O 5% are compared with 100% conventional gasoline fuel. These fueled single-cylinders spark ignition engine is studied for checking their performance and emission characteristics as per future emission norms. This work is performed on One-dimensional AVL Boost Simulation Software. The simulations predicted the performance and emission characteristics were far lesser than conventional 100% gasoline. These fuels meet the strict emission regulations of Euro VII. The main purpose of this investigation is to use alternative fuels to improve the performance and emission characteristics of the single- cylinder spark ignition engine and reduce the consumption of fossil fuel reserves. This investigation led to the conclusion that by using methanol 20% in 80% gasoline and micro-emulsion, fuel improves the power, BSFC (brake specific fuel consumption), thermal efficiency and combustion properties of the single-cylinder spark-ignition engine. The CO, HC and NOx emissions were also reduced for alternative fuel than 100% gasoline fuel. The novel water-based emulsion fuel showed the lowest value of NOx emissions as compared to blended 20% methanol with 80% gasoline and 100% gasoline fuel.

Minimizing loss of injected hydraulic fracturing fluids into shale along fracture-matrix boundaries is desired because imbibed water restricts gas production and wastes valuable water resources. This problem has motivated the addition of surfactants into water-based hydraulic fracturing fluids in order to reduce the capillary driving force for imbibition. Here, we show that reduction in interfacial tension and wettability alteration has negligible ability to reduce imbibition in deep gas reservoirs. The effectiveness of altering capillary forces acting at the wetting front also depends on the injection pressure acting at the fracture-matrix boundary. The pressure at the interface between the fracture and the shale matrix is constrained between the reservoir pore pressure and formation pressure (rock fracture pressure, also known as breakdown pressure of the rock) and increases with depth to magnitudes that greatly exceed that of capillary pressures. The analyses presented here show that even maximum alteration of interfacial properties that result in strongly hydrophobic interactions between the fracturing fluid and reservoir rock is incapable of significantly reducing imbibition in deep reservoirs. Instead of using surfactants, this analysis points to decreases in wellbore shut-in pressures and shut-in times as practical options for reducing imbibition losses of water-based fluids.

"The synthetic resins in printing inks are harmful to the environment because they are not biodegradable and emit volatile organic compounds. The printing industry has sought alternative printing inks to solve these issues. The aim of the work is to explore sustainable and environmentally friendly inks, without scarifying ink performance. To determine their performance and effect on print quality, soy proteins were investigated. Also, commercial and formulated acrylic inks were used as reference inks. From the results, the print density of soy protein water-based inks is higher than that of the reference inks. Moreover, they obtained a higher print gloss than the reference inks. The printing contrast values of soy protein water-based inks are relatively low. There was no considerable difference found in TVI values. Overall, the soy protein water-based inks produced a very competitive result in printability and presented high potential for replace synthetic components in current commercial inks."

Reasoning of particular mechanism of anomalous thermal transport behaviors is not identified yet for the nanofluids. In this research, the thermal conductivity of maghemite (MH) nanoparticles dispersed deionized water (DW) nanofluids (MH/DW) has been evaluated for the first time using the modified effective medium theories (EMTs). EMTs have been modified with the consideration of static and dynamic effects combinedly for the analysis of anomalous behaviors of thermal conductivity enhancements of the spherical nanoparticles dispersed nanofluids. MH nanoparticles (~20 nm) were synthesized using chemical co-precipitation techniques. MH/DW nanofluids were prepared with the varying MH nanoparticles loading in DW and thermal conductivity was measured using KD2 pro device. The thermal conductivity enhancement (~32 %) was found to be increased linearly with the increasing MH nanoparticle concentration and nonlinearly with the increasing temperature. Existing Maxwell and Maxwell Gantt EMA (MG-EMA) models exhibited awful under-prediction from experimental thermal conductivities of MH/DW nanofluids. Modified model with considering static and dynamic mechanisms of MH nanoparticles combinedly showed reasonably very good agreement with the experimental thermal conductivities of MH/DW nanofluids at elevated temperature. This modified model opens the new windows to analyze the insight of the thermophysical properties of various types of nanofluids by introducing potential parameters.

Efficacy of five water based insecticides on Schistocerca gregaria (Forskal), Locusta migratoria (Linnaeus),and multiple grasshoppers species applied as low volume (LV) and Ultralow volume (ULV) were tested. Obtained data indicated that descending order of insecticides efficacy were as follow: chlorpyrifos, thiamethoxam + chlorantraniliprole, spinetoram + methoxyfenozide, chlorantraniliprole then pyridalyl, in case of S. gregaria both spinetoram + methoxyfenozide and chlorantraniliprole were quite similar. Concerning spray characteristics, the effectiveness of spraying tested water based pesticides diluted with 30% Propylene glycol water mixture as ULV spray technique was obvious, where the droplets size, relative span, and number of droplets per cm2 were suitable for locust control.

This work investigates the efficacy of a biodegradable natural product, litchi leaves powder (LLP) as a filtration loss control agent in the water-based drilling fluid formulations. In order to evaluate the potential of litchi leaves powder (LLP), a strict protocol of experimentations according to API (American Petroleum Institute) standard has been followed. The experimental outcome showed that before hot rolling and after hot rolling of mud samples at 100 °C it was observed that 3–5% Concentration of LLP significantly increased the rheological parameters such as PV, YP and gelation of drilling fluid as compared to reference mud. Also, LLP reformed the filtration loss control characterization, suggesting a better biodegradable fluid loss reducing agent. After hot rolling at 100 °C for 18 h, the water-based drilling fluid with LLP as an additive showed a marked reduction in filtration control property as compared to reference Mud (RM). Experimental results concluded that 5% concentration of LLP significantly reduced the filtration loss of drilling fluid by 70.6% as compared to reference mud under the influence of 100 psi pressure. However, the conventional fluid loss additive CMC (LVG) reduced the filtration loss by maximum 67.5% as compared to reference mud. Therefore, LLP can be used as an alternative to CMC (LVG) in water-based drilling fluid with a maximum subsurface temperature of 100 °C.

The purpose of this study was to evaluate the controlled-release properties of nutrients from coconut water-based hydrogel. Hydrogels were prepared at varying proportions of gellan and xanthan gums such that the total weight of the gelling agents for all 11 formulations was 1% (w/w) in coconut water. The formulation of the hydrogel was selected using gravimetric analysis by evaluating the dissolution weight of the hydrogel in simulated gastric fluid and simulated intestinal fluid. Interestingly, hydrogel with 0.7% gellan gum and 0.3% xanthan gum showed the most tolerance towards simulated gastric and intestinal fluids over a 1-h period. The in-vitro release study was performed in simulated gastric fluid and followed by simulated intestinal fluid for about 2 h. The trend of release profile showed that the hydrogel had the ability to sustain the nutrients release over a period of 1 h. After 75 min, the release trend was static indicated the nutrients was released from the hydrogel. In conclusion, a coconut water-based hydrogel formulated with 0.7% of gellan and 0.3% of xanthan gum has demonstrated its controlled-release property as evidenced by its effectiveness in the sustained release of nutrients over a period of 1 h.

Due to its low toxicity and because they are environmentally friendly, water-based paints are the most employed in the world, mainly to coat buildings. In these systems, the water evaporation process is important to determine the final paint quality and should be carefully evaluated. This work evaluated the suitability of Crank’s model, solution of the Fick’s second law, to experimental drying data of water-based architectural paints to better understand this process. Therefore, the data were adjusted to the linearized and original model and the number of terms used in its approximation was varied. For each model, the diffusion coefficient of the water in the coating material and the coefficient of determination were calculated. The results showed that the use of the linearized model is not adequate to determine the diffusion coefficient, but the nonlinear adjustment of the original model can adjust the data for some paints. These results also suggest the addition of terms to the sum of the model to improve its quality in the initial stages of drying. DOI: http://dx.doi.org/10.17807/orbital.v13i1.1508

Waterborne polyurethane (WBPU) has the advantages of environmental, excellent film‐forming property and high bonding strength. However, the mechanical strength of waterborne polyurethane in coating products is not enough, and its wear resistance and softness are poor. In this paper, the Cellulose Nanocrystals (CNC) AQ3 obtained by acid hydrolysis of microcrystalline cellulose was successfully dispersed in the waterborne polyurethane matrix to prepare nanocomposite films with different contents. The mechanical properties, thermal properties, wear resistance and softness of the nanocomposite films were studied by Thermogravimetric (TG), tensile test, dry friction test and KES test. The morphology of CNC dispersed in waterborne polyurethane matrix was studied by Scanning electron microscope (SEM). The results show that the lower content of CNC was uniformly dispersed in the waterborne polyurethane matrix and the interaction between the two forms hydrogen bonds. Compared with waterborne polyurethane, the initial degradation temperature of the nanocomposite films made by adding only 1 wt% CNC increased by 50°C, the tensile strength increased by 179.3%, the wear resistance increased by 19%, and the minimum bending stiffness B reached 0.161 (gf·cm2). The results of this study can be used for textile coating applications, such as polyurethane synthetic leather.

The natural convection heat tranfer in annulate region confined between two homocentric cylinders were numerically studied in the present work. The annulus was filled by ethylene glycol / water based Titania nanofluid. Both internal and external cylinders are presereved at an isothermal hot and cold temperatures respectively, whereas, the upper and lower walls are adiabatic. The numerical solution is obtained by applying the finite volume method along with the SIMPLER, and TDMA algorithms. In the current study, the solid volumetric fraction is varied as (0 % ? ? ? 3 %), the volume ratios of EG to water are varied as (0:100 %, 40 : 60 %, 100:0 %), while both the Rayleigh number and radii ratio are considered fixed at (Ra = 104 and ? = 2). The obtained results indicated that, the average Nusselt number increases as the solid volumetric fraction and the volume ratio of ethylene glycol in the base fluid increase. Moreover, the velocity profiles reach their maximum value in the half region adjacent the internal hot wall when TiO2 – water nanofluid is used. Also, the temperature profiles decrease along the radial distance for all considered values of volume ratios of EG to water.

There is growing research into the links between blue space encounters, human health and wellbeing, and increasing interest in prescribing nature-based activities to promote physical activity, enha...

OBJECTIVES: To develop a science and risk based strategy to qualify a prefillable autoclavable cyclic olefin polymer (COP) syringe as a container for multiple drug products in a hospital pharmacy setting METHODS: Different extraction studies were performed with different solution characteristics: phosphate buffer batches (Na2HPO4 / NaH2PO4 in NaCl 0.9%) at different pH values, NaCl 0.9% batches, isopropyl alcohol (IPA) 5% in water and batches with Water For Injections (WFI) at different pH values. The filled syringes were terminally sterilised. The syringes were stored at room temperature (20°C±5°C).Following different monographs of the European Pharmacopoeia several tests were performed on the different batches. Analyses were performed at t=0, 1, 2, 3, 4, 5, 6, 9, 12, 18, 24 and 36 months for the general tests. For the subvisible particles, sterility and closure integrity a bracketing scheme was applied during 36 months.RESULTS: Low levels of extractables were measured for the different solutions. The test for subvisible particles, sterility and closure integrity all met predefined requirements. In the 5mL and 50mL syringes different concentrations of silicon were measured. Overall higher silicon concentrations were measured for the 50mL syringes.CONCLUSIONS: The chosen strategy for the qualification program provided an adequate understanding about the extractables that could leak from the syringes. The cyclic olefin polymer syringes including stopper and tip cap were found to be suitable as primary packaging materials for the production of water based products.

This article is devoted to obtaining a water-coal suspension with new technological properties. The development of the scientific and technical progress, the growth of the population and the improvement of its welfare led to the sudden increment of energy consumption, as a result, is the depletion of hydrocarbon raw materials. Therefore, by many foreign specialists, the beginning of XXI century is evaluated as the transition period in the development of the world power system. Accordingly, the tasks of power saving and ecological safety at work of power systems are urgent. The article describes the technology of obtaining a water-emulsion suspension with the help of the Uzgen coal basin of the Karadobo deposit in the Osh region of the Kyrgyz Republic. Briefly, it is relatively classified as a specific liquid-phase composite material with broad functional and technological capabilities.

This study aims to evaluate the effect of wheat flour as a natural and environmentally friendly material on the properties of water-based mud. Recently, many experiments have been conducted with various additives to improve the properties of drilling fluids. The effect of using wheat flour as a new additive to drilling fluid was studied to improve rheological and filtration properties. In the laboratory several samples of water-based mud were prepared, different concentrations of wheat flour from 1 wt% to 7 wt% were added to the mud and tested by using a Fann 35 viscometer, 140 Fann Mud balance, and an API LT-LP filter press. The results showed that adding 7 wt% of wheat flour was the optimal concentration. It was found that the apparent viscosity and yield point increased by 50% and 35%, respectively, when 7 wt% of wheat flour was added to the water-based drilling fluid. Likewise, the fluid loss rate was reduced by 25% when using the same concentration of wheat flour.

Although the increment the performance of photovoltaic thermal (PVT) systems by using the nanofluids as working fluids have gained the attention of researchers during the last two decades, there is still, a lack in the literature study associated to this application. This study contributes to the investigations and researches of applying the nanofluids to increase the performance of PVT collectors. A flat non-concentrating PVT collector has been designed, constructed and, outdoor tested in Karabuk University, Turkey. The considered working fluids in this study are multiwall carbon nanotubes (MWCNT), and graphene nanoplatelets dispersed in water as a base fluid with a concentration of 0.5 wt.%. The experiments were run with a volume flow rate of 0.5 L per minute for the aforementioned nanofluids and distilled water (as a reference fluid). The study results have shown and revealed that the MWCNT-water nanofluid presented a better performance in terms of eletrical energetic efficiency compared to graphene nanoplatelets-water nanofluid and distilled water, while graphene nanoplatelets-water nanofluid revealed the highest thermal energetic efficiency. Moreover adding thermal unit to photovoltaic module enhanced the total energetic efficiency by 53.4% for distilled water, 57.2% for MWCNT-water, and 63.1% for graphene-water.

This study reports a simple approach to prepare a nano-TiO2-Sb-Ni yellow ink-jet ink. Yellow pigments, in terms of their morphology and color appearance, were synthesized by changing Ni/Sb molar ratios and calcination temperatures. Moreover, the particle size of optimal nano-TiO2-Sb-Ni pigment controlled by CTAB and PVP in a co-precipitation process. TGA, spectrophotometry, and XRD were used to characterize the prepared nano-TiO2-Sb-Ni pigments. SEM and TEM were used to investigate the morphology and size of the prepared nano-pigments, respectively. Finally, the synthesized spherical nano-pigment had an average diameter of 65 nm was well dispersed in water. A general ink-jet printer printed the stable, homogenous nano-ceramic ink. Ultimately, the more yellow appearance could be obtained through increasing the number of printing runs.

The increasing demand for deeper drilling and more complicated wells fastens the way for improved drilling fluid (mud) technologies and promising additives. Several studies have shown numerous improvements in mud characteristics upon using ilmenite compared to the commonly used weighting materials. This study aims at investigating the removal of filter cake deposited by ilmenite water-based drilling fluid under harsh conditions using low-concentration (7.5 wt%) of hydrochloric acid (HCl) and chelating agent (HEDTA) to prevent iron precipitation during reaction. API filter press was used to conduct the filtration tests and generate the filter cake at a pressure ~ 300 psi and temperature ~ 250°F. Different sandstone cores of 2.5-in. diameter and 1-in. thickness were used to simulate the formation during filtration. Filtrate fluids were collected for 30 minutes as per API procedures and computerized tomography (CT) scan was used to characterize the cores with the deposited filter cakes. The filter cakes were soaked with HCl–chelate solution for six hours. Cores with the remaining filter cakes were CT scanned again. Effluent solutions resulting from the aforementioned soaking process were analyzed using inductively coupled plasma (ICP). Scanning electron microscopy–energy dispersive spectroscopy (SEM-EDS) was used to analyze the dried filter cakes and remaining residue. CT scan and SEM-EDS showed two layers of the filter cake with different densities but similar elemental composition. Using 7.5 wt% of HCl can partially remove the filter cake generated by ilmenite water-based drilling fluids. Adding the chelate showed minimal impact on the filter cake removal-efficiency; however, it helped nullify the corrosion issues during the treatment. This study provides a step forward on the way to chemically remove ilmenite-based filter cake using low acid concentration and virtually overcome corrosion issues encountered while acidizing.

In the current study, an investigation possibility is introduced regarding the appearance of the so-called formation damage phenomenon in case of overbalanced drilling of compacted sandstones with water-based mud and the fracturing of the layers with water-based fracturing fluid. The results presented in the study are part of a series of experiments.

Background/Aim: To develop and validate an easy-to-use and cheap method capable of producing placebo from tap water for medicinal water efficacy trials. Patients and Methods: Patients were divided into two groups, medicinal water and tap water group. A single 20-minute-long treatment was performed in bathtubs. Patients were asked four times during the bath to tell if they were treated with medicinal water, tap water, or could not decide. Patients were scored, one point was given for each correct answer. Results: A total of 174 patients were enrolled. No significant differences were found either between the average scores or the answers of the two groups. Being familiar with the Harkány medicinal water did not influence the rate of correct answers either. There was no statistically significant difference in the number of changes of opinions between the two groups. Conclusion: The used method is appropriate for producing a validated placebo from tap water.

Early diagnosis of cancer has become one of the effective ways to prevent and treat cancer. At present, magnetic resonance imaging (MRI) diagnosis based on nanosized iron oxide with no toxicity and excellent biocompatibility has attracted much attention. But the poor stability of magnetic fluid (MF) is becoming more and more prominent. In view of the poor stability of MF, the dodecanethiol-poly(methacrylic acid) (DDT-PMAA) as an outer shell was prepared for the MFs (Fe3O4@DDT-PMAA MF) to improve the stability. We also compared the amount of reactants, the ratio of reactants, and the reaction temperature, and finally screened out the best reaction conditions, so as to get more stable products. The stability of the system was studied by visual observation, stability index (I), and magnetic weight change. The results demonstrated that Fe3O4@DDT-PMAA can be stable for more than 60 days. The T 1 mapping image showed that the longitudinal relaxivity (r 1) value was 6.9 mM−1 s−1 (1.5 T, room temperature), which was higher than the commercial contrast agent SHU-555 (r 1 = 2.9 mM−1 s−1), but the transverse relaxivity (r 2) value accounted for 64.48% of the commercial contrast agent Feridex (r 2 = 67.8 mM−1 s−1, 1.5 T, room temperature) because the outermost layer was encapsulated by a polymer. In addition, the imaging effect was more vivid and there was almost no background interference of T 1- and T 2-weighted images in vivo, which indicated that the Fe3O4@DDT-PMAA MF exhibited excellent potential in MRI applications.

Water-based manufacturing processes are under development for greener manufacturing of lithium ion batteries but their environmental impacts are unclear with new introduced materials and a large consumption of deionized water. We report a life cycle assessment (LCA) study on the water-based manufacturing of the most popular NMC-graphite battery pack configured with 57 kWh capacity. A life cycle model has been developed based on experimental and mathematical studies of the water-based manufacturing processes. Per kg battery pack produced, the water-based manufacturing can reduce the manufacturing energy by 43% and lower the cradle-to-gate life cycle impacts by 0.6%∼88% over conventional battery manufacturing.

A new metal–organic framework (MOF) compound [Mn2(2,2′-bca)2(H2O)2]n (Mn-MOFs) was successfully synthesized by solvothermal method, and Mn-MOFs@Zn material was prepared by loading zinc phosphate onto Mn-MOFs by ball milling, then Mn-MOFs@Zn was added to the water-based acrylic paint to prepare Mn-MOFs@Zn@acrylic coating. The AC impedance test results showed Mn-MOFs@Zn@acrylic coating has higher corrosion inhibition performance and stability to mild steel when compared with blank coating. The impedance modulus of the blank coating in the low frequency region decreased by 90%, and the Rct showed a trend of first increasing and then decreasing over time, the maximum Rct was only 303.8 Ω, which was only Mn-MOFs@Zn@acrylic coating one-seventh of the Rct value. The artificial scratch experiment showed that the Mn-MOFs@Zn@acrylic coating only slightly corrodes at the scratches, because Mn-MOFs@Zn material made the coating a self-repairing function and improved the durable anticorrosion performance of the acrylic coating.

This article is devoted to obtaining a water-coal suspension with new technological properties. The article describes the technology of obtaining a water-emulsion suspension with the help of the Uzgen coal basin of the Karadobo deposit in the Osh region of the Kyrgyz Republic. Briefly, it is conventionally classified as a specific liquid-phase composite material with broad functional and technological capabilities.

This article is devoted to obtaining a water-coal suspension with new technological properties. The development of the scientific and technical progress, the growth of the population and the improvement of its welfare led to the sudden increment of energy consumption, as a result, is the depletion of hydrocarbon raw materials. Therefore, by many foreign specialists, the beginning of XXI century is evaluated as the transition period in the development of the world power system. Accordingly, the tasks of power saving and ecological safety at work of power systems are urgent. The article describes the technology of obtaining a water-emulsion suspension with the help of the Uzgen coal basin of the Karadobo deposit in the Osh region of the Kyrgyz Republic. Briefly, it is relatively classified as a specific liquid-phase composite material with broad functional and technological capabilities.

Barite settling is one of the common drilling fluid issues encountered while drilling deep wells. In this study, the effect of perlite on the properties and stability of water-based drilling fluid was investigated. Perlite is an inexpensive additive used in different industrial applications such as bricks, concrete, thermal insulators, sludge absorbents, fillers, tiles, ruminants, and poultry. Perlite additive was also introduced to the oil industry in drilling applications as an effective fluid loss control agent to reduce the drilling fluid invasion into the formations. Perlite was added to the drilling fluid in various concentrations, ranging between 0 and 3.0 lb/bbl. The sag test was performed to assess the drilling fluid's stability under dynamic and static conditions at a temperature of 120/250 °F. Then, the impact of perlite on the properties of drilling fluid was assessed by measuring the density and pH at room temperature. While the rheological, viscoelastic, and filtration properties were evaluated at 250 °F. This study showed that an increase in perlite concentration, from 0 to 3 lb/bbl, slightly reduced the pH of the drilling mud; however, all of the values were within the acceptable pH range (9-11). In contrast, this concentration of perlite had an immeasurable impact on drilling fluid density. Perlite enhanced the drilling fluid's homogeneity and stability by reducing the dynamic and static sag factors, and 3.0 lb/bbl perlite was adequate to eliminate barite sag at a temperature up to 250 °F. Perlite was found to be effective in improving the rheological and viscoelastic properties. A significant enhancement of filtration properties was observed by the reduction in filtrate volume and filter cake thickness by 64 and 31%, respectively.