Search

I hardly need to talk about that. how important is the timely and rapid recognition of infectious diseases such as relapsing fever and malaria. Since the causative agents of these diseases in a certain period of the disease are in the peripheral blood, the usual method of recognizing these diseases is a blood test.

The article indicates the features of the use of aqueous solutions of surfactants in gas and oil production. The defining parameters of such solutions which are investigated at a choice of the applied surfactants are specified. The analysis of the known methods for determining the interfacial tension by the rotating drop method showed the possibility of improving the procedure for calculating the interfacial tension to simplify it. In the article it is offered to improve a technique of calculation of an interfacial tension by a method of a fixed rotating drop with application of the equation of Vonnegut with a correction factor. The value of the correction factor was obtained from the calculations of the contours of the fixed rotating drops, as well as the calculation of the interfacial tension using the Vonnegut formula based on the calculated contours. It is established that the correction factor can be represented as a functional dependence on the ratio of diameter to the length of the rotating drop. To verify this relationship, the correlation coefficients between the correction factor and the size of the rotating drop were calculated. During the experimental test, the possibility of using the developed technique to study the parameters of aqueous solutions of surfactants with petroleum products was confirmed.

The buoyant drop method is a ubiquitous tool for addressing phenomena at the liquid-liquid interface via the determination of the interfacial tension (IFT) between two immiscible phases. Here, the focus is on how electrolytes (in an aqueous phase) and carboxylic acids (in a decane phase) impact the interfacial layer between the two phases. The IFT measurement provides a single number, which is not fulfilling when it comes to deducing information about a complex multiparameter system. Furthermore, the temporal evolution of IFT does not always reach a steady-state value on a time scale, which is realistic to use for comparative studies. We have investigated the temporal evolution of IFT in a series of experiments with varying compositions of the decane-carboxylic acid phase and the brine phase. The results show that there are at least two opposing effects in play. For water-soluble acids, the IFT initially increases with time until a turnover point is reached from where there is a gradual decay. The IFT at the turnover point is close to that of the pure water-decane system. For a poorly water-soluble acid, the IFT shows a much smaller increase and the turnover happens much faster. For a water-soluble acid, there is a high degree of sensitivity toward the electrolyte; it determines the position (in time) of the IFT peak and the steepness of the subsequent decay. Now, if the phases are reversed, that is, by placing a drop of brine in the decane-surfactant phase, the IFT decreases with time regardless of the acid and with little impact of the electrolyte and its concentration in the brine. We propose an explanation for the observed behavior (supported by COSMO-RS calculations), which is based on diffusion in and out of the two phases, solubility, and interfacial reactivity (i.e., aggregation between electrolytes and carboxylic acids).

The contribution of non-linear fluid flow effects to the damping of surface oscillations in the oscillation drop method was investigated in a series of experiments in an electromagnetic levitation device installed on the International Space station, ISS-EML. In order to correctly evaluate the damping time constant from measured surface oscillation decays the effect of a modulated signal response on measured surface oscillation decay curves was investigated. It could be shown that various experimentally observed signal patterns could be well represented by a modulated response. The physical origin of such modulations is seen in rotation and precession. Over a temperature range of 220 K covered by different surface oscillation excitation pulses with an initial sample shape deformation of 5 – 10% the amplitude of surface oscillations as a function of time could be very well represented by a Lamb type damping with a temperature dependent viscosity. A direct comparison of surface oscillation decay times measured in the same temperature range but for different oscillation amplitudes showed no non-linear contribution to the damping time constant with a confidence level better 10%.

High-throughput measurement of cells perturbed using libraries of small molecules, gene knockouts, or different microenvironmental factors is a key step in functional genomics and pre-clinical drug discovery. However, it remains difficult to perform accurate single-cell assays in 384-well plates, limiting many studies to well-average measurements (e.g. CellTiter-Glo®). Here we describe a public domain “Dye Drop” method that uses sequential density displacement and microscopy to perform multi-step assays on living cells. We use Dye Drop cell viability and DNA replication assays followed by immunofluorescence imaging to collect single-cell dose-response data for 67 investigational and clinical-grade small molecules in 58 breast cancer cell lines. By separating the cytostatic and cytotoxic effects of drugs computationally, we uncover unexpected relationships between the two. Dye Drop is rapid, reproducible, customizable, and compatible with manual or automated laboratory equipment. Dye Drop improves the tradeoff between data content and cost, enabling the collection of information-rich perturbagen-response datasets.

The aim of this study was to evaluate the development, yield and its components of soybean sown in hill drop method with variation in hole spacing, compared to the conventional sowing method in lines. The experiment was conducted in a randomized block design, with six treatments and four replications, using the variety M7739 RR IPRO with four plans per hole. The treatments consisted of population variation from 50 to 150% of the recommended one, obtained by the holes spacing alteration and a control sowed in lines with the recommended population. The control was compared to the other treatments using the Dunnett test and the hole spacing effect was evaluated by regression. The cultivar 7739 RR IPRO responds to hill drop sowing, obtaining even in lower populations, yields similar to the conventional sowing in lines. The highest yields in the hill drop sowing method are obtained in the higher populations, with a linear decrease in yield with an increase in hole spacing. Increasing hole spacing increases the number of pods and branches and reduces leaf cover, light interceptcion, plant height and first pod height.

Postharvest damage, leading to loss and waste, continues to be a significant problem in the fresh produce industry. Trays, designed to reduce fruit-to-fruit contact, are utilized by the apple industry to minimize bruising of whole apples. During distribution, packaged apples are subjected to various supply chain hazards, which may lead to bruising damage. Currently, molded fiber (MF) and expanded polystyrene (EPS) trays transport whole apples from the packhouse to the retail outlet. Mechanical shock, by free-fall drop method, was used to evaluate the performance differences between the two trays and quantify the bruising characteristics of the apples. Results showed that the EPS trays provided better shock protection to the apple as compared to the MF tray, reducing the impact acceleration by more than 70%. Additionally, the bruise susceptibility was 40% less for the apples packaged inside the EPS trays, regardless of drop height. However, apples packaged in the middle layer trays were most susceptible to bruising damage, regardless of tray type.

The article characterizes the impact test method using Drop-Tower Impact Test with the registration of the value of force and energy of breaking. Based on sources, the possibilities and scope of the current application of this method were determined and the current state of knowledge on the results of these tests was reviewed. In order to determine the possibility of using the method in impact tests of high strength steel joints, investigations of hybrid PTA - GMA welding conditions on impact strength of joints of MART S1300QL steel were carried out. In particular, the influence of t8/5 cooling time on the impact strength of welded joints by the Drop - Tower Impact Test method was determined. It has been shown that the use of dropping machine with computer-based registration of breaking force and energy values was possible in the case of impact strength testing of UHSS welded joints and enabled precise analysis of the energy distribution dynamics absorbed by the tested.

A correction to this paper has been published: https://doi.org/10.1007/s10765-021-02870-5

The use of 3D cell culture has been a major step in developing cellular models that can mimic physiological tissues. Traditional 2D cell cultures are often unable to accurately represent the cellular functions and responses that are present in tissues, as a result, research findings based on 2D cultures tend to be skewed with limited predictive capability. 3D cell cultures can be grown from cells obtained from cancer organoids in patients. These models are useful for understanding disease mechanisms and exploring drug therapeutics in areas such as toxicity and efficacy. In order to gather more physiologically relevant data, a variety of 3D cell culture techniques have been developed to mimic the in vivo characteristics of physiological tissues. This protocol describes in vitro generation of U-251MG spheroids using the hanging drop method. Advantages of using hanging drop plate method are, able to produce uniform size spheroids, low cost, comfortable to handling and suitable for short term culture. The main downside of this method is medium change, different drug treatment at different time points are impossible and labor intensive. This method uses the Perfecta3D hanging drop plate, a novel cell culture device that simplifies the process of spheroid formation, testing and analysis. Rather than having to invert the plates which often results in spillage or detachment, these plates are designed to create hanging drops using a plateau structure at the bottom of the plate. We used HDP1096 Perfecta3D® 96-well hanging drop plates for tumorsphere construction from 3D Biomatrix and adapted protocols published by: Hikage, F., Atkins, S., Kahana, A., Smith, T. and Chun, T., 2019. HIF2A–LOX Pathway Promotes Fibrotic Tissue Remodeling in Thyroid-Associated Orbitopathy. Endocrinology, [online] 160(1), p.3. Available at: . Moraes, G., Wink, M., Klamt, F., Silva, A. and Fernandes, M., 2020. Simplified low-cost methodology to establish, histologically process and analyze three-dimensional cancer cell spheroid arrays. European Journal of Cell Biology, [online] 99(5), pp.2-3. Available at: . sigmaaldrich.com. n.d. HDP1096 Perfecta3D® 96-Well Hanging Drop Plates Protocol. [online] Available at: .

W360 is a hot work tool steel produced by voestalpine BÖHLER Edelstahl GmbH & Co KG, a special steel producer located in Styria, Austria. Surface tension and density of liquid W360 were studied as a function of temperature in a non-contact, containerless fashion using the oscillating drop method inside an electromagnetic levitation setup. For both, surface tension and density, a linear model was adapted to present the temperature dependence of these measures, including values for the uncertainties of the fit parameters found. The data obtained are compared to pure iron (with 91 wt% the main component of W360), showing an overlap for the liquid density while there is a significant difference in surface tension (− 5.8 % at the melting temperature of pure iron of 1811 K).

Characterization of surfactant effectiveness and thus an evaluation of their performance in a wide range of emulsion technologies requires a precise determination of key parameters including their critical micelle concentrations as well as their ability to lower the surface tension at interfaces. In this study, we describe a new approach to quantify marginal variations in interfacial tension of surfactant stabilized fluid interfaces. The method is based on a unique chemical-morphological coupling inside bi-phasic oil-in-water Janus emulsions that undergo dynamic morphological transitions in response to changes in the surfactant type, concentration, ratio, and configuration. Variations in Janus droplet morphologies are readily monitored in-situ using a simple side-view imaging setup, resulting in a fast, convenient, cost-effective, time-, and sample-saving technique for the characterization of classical surfactant systems. In addition, the reported method facilitates a monitoring of triggered changes in surfactant effectiveness, e.g. invoked by external triggers, and thus proves particularly useful for the in-situ analysis of stimuli-responsive surfactants and emulsions.

The direct current potential drop method (DCPDM) is widely used to determine the crack length in fatigue experiments. In practice, some special features of this method must be considered. Aside from general information on the experimental setup and calibration, some special features of the method, such as the influence of the ambient atmosphere and the application of the method to ferromagnetic materials, are presented and discussed. In addition, with the multiple potential drop measurement, a method is presented which improves the resolution of the DCPDM for detection of cracks and allows to determine crack initiation sites. The capabilities provided by this method are demonstrated on the basis of measurements undertaken on notched round bars and single edged notched specimens.

Background: The interval between stimulus and response is called reaction time. It measures the sensorimotor function and performance of an individual. It involves stimulus processing, decision making and response programming. Many factors such as age, gender, handedness, physical fitness, sleep, fatigue, distraction, personality type and type of stimulus have been shown to affect reaction time. Thus the aim of this study was to assess the effect of body mass index, handedness and gender on reaction time.Methods: A cross-sectional study was conducted in the Department of Physiology, Kathmandu University School of Medical Sciences, from October 2019 to December 2019, among 113 student volunteers. Height and weight were recorded and body mass index was then calculated. In ruler drop method, the students were made to sit with their forearm resting on a flat horizontal table surface, with their open hand at the edge of the surface. When the examiner suspended and released the ruler vertically the students were instructed to catch it as quickly as possible.Results: Females had a faster reaction time than males when testing either hand (178.46±17.56 Vs 195.99±15.67; right hand) and (184.25±17.02 Vs 199.57±15.91; left hand). In females, right hand responded faster than left hand. In both gender, reaction time was faster in normal weight compared to overweight individuals but it was statistically insignificant.Conclusions: Females responded faster than males. Right hand had shorter reaction time than left hand in females. Reaction time was insignificantly prolonged in overweight individuals. Keywords: Body mass index; reaction time; ruler drop method

Mixtures of fluorinated and non-fluorinated ionic liquids (ILs) show a distinct structural organization in the bulk and at the surface. To understand how such microscopic effects influence the macroscopic bulk and surface properties of IL mixtures, knowledge of corresponding thermophysical properties including viscosity and surface tension is required yet lacking. With the intention of investigating surface enrichment effects of the fluorinated IL [PFBMIm][PF6] (3-methyl-1-(3,3,4,4,4-pentafluorobutyl)imidazolium hexafluorophosphate) in mixtures with the structurally similar, non-fluorinated IL [C4C1Im][PF6] (1-butyl-3-methylimidazolium hexafluorophosphate) observed with angle-resolved X-ray photoelectron spectroscopy (ARXPS), the pendant drop method and surface light scattering (SLS) were applied in the present study to determine surface tension and dynamic viscosity between (293 and 368) K. By adding small amounts of [PFBMIm][PF6] up to 9 mol %, a distinct increase in the viscosity and decrease in the surface tension of the mixtures relative to the properties of pure [C4C1Im][PF6] was found. This behavior reflects the nanosegregated structure in the bulk and at the surface of the binary IL mixtures. Using the results about the pronounced surface enrichment of the fluorinated chain of [PFBMIm][PF6] quantified by ARXPS, a linear mixing rule for the surface tension of the IL mixtures based on the surface tensions of the pure ILs and the surface concentration of their most surface-active groups is suggested.

The surface tensions of aqueous cetyltrimethyl ammonium bromide and four polyethylene glycols were measured experimentally at the temperature of 298.15 K and the pressure of 1 atm. Then the surface tensions of aqueous (cetyltrimethyl ammonium bromide + polyethylene glycols) were measured at different concentrations. These measurements were conducted with the pendant drop method. The surface tensions of these aqueous solutions were described by using the equality of chemical potentials at the interface and bulk liquid. The calculated results showed a good agreement with experimental measurements, so the model was successfully applied to aqueous cetyltrimethyl ammonium bromide, polyethylene glycols, and their mixtures. Moreover, the surface coverage, molar surface area, and surface-to-solution distributions were determined by this model. The values of critical micelle concentration were obtained through surface tension measurements for each aqueous solution. The presence of polyethylene glycols increased the values of the critical micelle concentration and decreased the surface coverages of cetyltrimethyl ammonium bromide.

This paper reports the experimental values of the interfacial tension between a gas mixture (CO2 + H2) and water measured with the pendant drop method. The measurements were conducted for temperatures from 271.2 K to 280.2 K and pressures up to 7.0 MPa, at increments of 1 MPa. These temperature-pressure ranges were nearly close to the (CO2 + H2) hydrate-stability-zone but each result is obtained without existence of any hydrate. The temperature dependency of the interfacial tension in this system could not be observed, but the interfacial tension decreased almost linearly with increasing pressure, indicating that the observed decrease was caused by an increase in adsorption of the gas phase onto the liquid water with pressure. The gradient of the interfacial tension, with respect to the pressure, was confirmed to be determined by the gas phase composition. The interaction between gases has a marginal influence on the interfacial tension between the (CO2 + H2) gas mixture and water.

In total, 13 commercial wheat cultivars around China and four races of Puccinia striiformis f. sp. tritici (namely, CYR32, CYR33, G22-9, and G22-14) were employed for a test of relative parasitic fitness (RPF) using the drop method. The RPF values were measured, including the urediniospore germination rate, the latent period, the uredinial length, the uredinial density, the infection area, the sporulation intensity, the lesion expansion speed, and the sporulation period. The results indicated that the parameters of relative parasitic fitness of the four P. striiformis f. sp. tritici races on the 13 wheat cultivars were significantly different (P = 0.00) in sporulation intensity, lesion expansion speed, uredinial length, sporulation period, uredinial density, and latent period. The urediniospore germination rates of the four P. striiformis f. sp. tritici races for the test were significantly different (P = 0.00), whereas no correlation with the different cultivars was observed (P = 1.00). The infection areas of the tested races on the different cultivars were significantly different (P = 0.00) but there were no obvious manifestations among the various races (P = 0.20). Principal component analysis (PCA) showed that the sporulation intensity represented sporulation capacity and scalability, the latent period indicated infection ability, and the urediniospore germination rate represented urediniospore vigor, all of which fully contributed to the RPF in the interaction of the four races and 13 wheat cultivars, which was calculated by the following formula: RPF = (sporulation intensity × urediniospore germination rate)/latent period. The sporulation and infection of G22-9 on the 13 large-scale cultivated cultivars were the highest, and the RPF of G22-9 was higher than that of the predominant races, CYR32 and CYR33. This result suggested that G22-9 could become a new predominant race and potentially cause epidemics of wheat stripe rust in China. To prevent potential epidemics, susceptible wheat cultivars should be withdrawn from production and breeding programs should reduce the use of Yr10 and Yr26 and use other more effective resistance genes in combination with nonrace-specific resistance for developing wheat cultivars with durable resistance to stripe rust.

The propagation of short cracks covers the main part of the lifetime of cyclic loaded components. Thus, investigations in this field are necessary to enable reliable lifetime predictions. To investigate the influence of different crack initiation scenarios on the cyclic lifetime, SEN-specimens were fatigued under constant stress amplitude. For additional support of the crack initiation in some specimens a single overload was introduced after 200 cycles, in others the crack initiation was forced by laser cuts in the notch root. In all experiments, the crack length was measured with a high-resolution DC-potential drop method. This investigation approves and explains the relationship between the cyclic lifetime and the presence of steps on the fracture surface, as a reason of a retarded crack coagulation. The results clearly indicate that the scatter of the cyclic lifetime is determined by the differences in the crack initiation scenarios. Further on, a significant influence of a single overload on the cyclic lifetime can be verified.

During the actual operation of an ASHP unit installed in different climate regions, ambient operating conditions can vary constantly over an entire heating season, thus the actual output heating capacity of ASHP units may vary significantly from region to region. To enable a convenient evaluation of output heating capacity of a space heating ASHP unit installed in different climate regions, regional performance evaluation indexes including T a ′ ¯ , HERR(Ta’), βTa and βRH based on ETD method have been developed. These evaluation indexes are generalized and can be used to evaluate the regional performance of ASHP units operated in any regions. It can also be used to specify the key factors affecting the operating performances of ASHP units in different regions. With the developed evaluation indexes, the regional operating performances of ASHP units installed in 278 Chinese cities were evaluated. The results demonstrated that the total output heating energy for ASHP units operated in Southern Chinese provinces may be lower than those in Northern China. In Shanghai, T a ′ ¯ at −6.0 °C is lower than that at −3.0 °C in Beijing, suggesting the total output heating energy from an ASHP units operated in Shanghai over an entire heating season would be lower than that in Beijing. Furthermore, in southern Xinjiang and northern Fujian Provinces, the total output heating energy from ASHP units may be higher than those operated at the nominal condition. In addition, in Tibet, Beijing, Liaoning, etc., the total output heating energy from the ASHP units would be affected more by Ta, thus ASHPs’ manufacturers are recommended to develop ASHP units suitable for operation in low temperature ambient. In most regions in southern China, RH would affect more on the total output heating energy from the ASHP units, thus ASHPs’ manufacturers are recommended to develop ASHP units having frosting suppression provisions and accurate defrosting measures.

Density, surface tension and viscosity of five food oils were experimentally measured using the Archimedean method, Pendant drop method, and Brookfield viscometer respectively. Measurements were pe...

Pancreatic cancer exhibits a worst prognosis owed to an aggressive tumor progression i.a. driven by chemoresistance or tumor-stroma-interactions. The identification of candidate genes, which promote this progression, can lead to new therapeutic targets and might improve patient's outcome. The identification of these candidates in a plethora of genes requires suitable screening protocols. The aim of the present study was to establish a universally usable device which ensures versatile cultivation, screening and handling protocols of cancer cells with the 3D spheroid model, an approved model to study tumor biology. By surface modification and alternative handling of a commercial 384-well plate, a modified device enabling a) 3D cultivation either by liquid overlay or by a modified hanging drop method for b) screening of substances as well as for tumor-stroma-interactions c) either with manual or automated handling was established. The here presented preliminary results of cell line dependent dose-response-relations and a stromal-induced spheroid-formation of the pancreatic cancer cells demonstrate the proof-of-principle of the versatile functionality of this device. By adapting the protocols to automation, a higher reproducibility and the ability for high-throughput analyses were ensured. This article is protected by copyright. All rights reserved

We describe a new measurement method for liquid–liquid interfacial tension via a floating droplet profile (floating drop method), on a liquid. The accuracy of the floating drop method was confirmed for an oil-aqueous solution system. Specifically, we measured the interfacial tension between a floating rapeseed oil droplet and a 0.2% aqueous solution of polyoxyethylene alkyl ether sulfuric acid ester salt. In addition, it was confirmed that the tensile balance at the edge of the oil droplet floating on the aqueous solution, which is known as Neumann’s triangle, is satisfied in the present system.

Coiled tubings are widely used in oil and gas industries. Fracture toughness test of coiled tubing is a challenge. Non-standard specimen has to be used due to its geometrical difficulties, ie small thickness and diameter. Taking into account these factors, fracture toughness resistance curves, J-R curves, of coiled tubings were determined using the Spb method for the first time. The separability parameter, Spb is defined as the load ratio between two specimens at constant displacement, a precracked one that exhibits crack growth during its test and a blunt notched specimen with constant crack length when tested. Spb method, which uses Spb parameter, estimates stable crack growth in fracture toughness tests. It has been applied to different standardized specimen geometries. In this work, the method is applied to non-standard coiled tubing specimens. The geometry function was experimentally obtained testing four-point bending specimens. Stable crack growth results are compared to those measured using DC potential drop method used as reference method. Encouraging results were obtained. Fil: Wainstein, Jessica Elvira. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge; Argentina Fil: Perez Ipiña, Juan Elias. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Comahue. Facultad de Ingeniería. Grupo de Mecánica de Fractura; Argentina

Interfacial tension (IFT) is crucial for characterizing the phase and interphase behavior in the enhanced oil recovery (EOR) process. CO2 and N2 are commonly used as injection gases in the EOR process. In this work, an experimental apparatus using the pendent drop method was adopted to measure IFTs for the EOR process with different injection gases, temperatures (40.0–120.0 °C) and pressures (0.22–17.32 MPa). The relative Gibbs adsorption isotherm (Γij) of a species i on species j were calculated by the experimental IFTs. Theoretically, new correlations were proposed to predict paraffin IFTs for pure CO2 and mixture gas (CO2 + N2) injection. A total of 561 and 268 experimental IFTs were used to derive the correlations for pure CO2 and mixture gas injection, respectively. The square of correlation coefficient (R2), root mean square error (RMSE) and average absolute relative deviations (AARD) for pure CO2 were 0.9884, 0.58 and 5.45%, respectively. For the mixture gas injection, the R2, RMSE and AARD of the correlation were 0.9851, 0.57 and 4.47%, respectively.

Surface tensions of aqueous solutions of citric acid (unsaturated solutions and solutions with microcrystals) were measured in the temperature range from 283.15 K to 323.15 K. They were determined by the pendant drop method. Their values are compared with those that exist in the literature. Together with measured surface tensions, the corresponding densities were also determined by using an oscillating tube densimeter. Basing on measured densities and surface tensions, the parachor values and apparent molar volumes of aqueous citric acid solutions were calculated and discussed.

There are two techniques that can be used to improve the print quality of an inkjet printer, namely binary and greyscale techniques. In the greyscale technique, the method used is the multi drop ejection method. In the multidrop ejection method, it is more difficult to control droplet behaviour because the possibility of residual vibration and crosstalk will be higher, which can cause satellites and ligaments that can make poor print quality. In this study, we reveal how to control droplet behaviour in a multidrop ejection method so that it can produce good quality droplets. The comparison of droplet image that generated from basic waveform with the waveform using preliminary and suppressing vibration, without and with adjustments of actuation voltage was also studied.

Al-Ti-based alloys are of enormous technical relevance due to their specific properties. For studies in atomic dynamics, surface physics and industrial processing the precise knowledge of the thermophysical properties of the liquid phase is crucial. In the present work, we systematically measure mass density, ρ (g cm−3), and the surface tension, γ (N m−1), as functions of temperature, T, and compositions of binary Al-Ti melts. Electromagnetic levitation in combination with the optical dilatometry method is used for density measurements and the oscillating drop method for surface tension measurements. It is found that, for all compositions, density and surface tension increase linearly upon decreasing temperature in the liquid phase. Within the Al-Ti system, we find the largest values for pure titanium and the smallest for pure aluminum, which amount to ρ(L,Ti) = 4.12 ± 0.04 g cm−3 and γ(L,Ti) = 1.56 ± 0.02 N m−1; and ρ(L,Al) = 2.09 ± 0.01 g cm−3 and γ(L,Al) = 0.87 ± 0.06 N m−1, respectively. The data are analyzed concerning the temperature coefficients, ρ T and γ T, excess molar volume, V E, excess surface tension, γ E, and surface segregation of the surface active component, Al. The results are compared with thermodynamic models. Generally, it is found that Al-Ti is a highly nonideal system.

The knowledge of thermophysical properties of liquid Co-Si alloys is a key requirement for manufacturing of composite materials by infiltration method. Despite this need, the experimental and predicted property data of the Co-Si system are scarce and often inconsistent between the various sources. In the present work the mixing behaviour of Co-Si melts has been analysed through the study of the concentration dependence of various thermodynamic, surface (surface tension and surface composition) and structural properties (concentration fluctuations in the long-wavelength limit and chemical short-range order parameter) in the framework of the Compound Formation Model (CFM) and Quasi Chemical Approximation for regular solutions (QCA). In addition, the surface tension of the Co22·5Si77.5 (in at%) eutectic alloy, that is proposed to be used as the infiltrant, has been measured by the pendant drop method at temperatures ranging from 1593 to 1773 K. The results obtained were discussed with respect to both, temperature and concentration, and subsequently compared with the model predictions and literature data.

The synthesis of silicon microspheres is of outmost importance, especially for the production of optical and electrical devices due to their unique properties displayed by this material. In this paper, we review the research on the synthesis of silicon microspheres, including one physical method, the drop method and several chemical methods, such as vapor-phase reaction, vapor-solid reaction, liquid phase reaction and magnesio-thermal reduction method. The formation mechanisms for silicon microsphere particles are also summarized.

Recovery of lithium ions from salt lake brine is becoming more important because of the rapid increase in projected demand for lithium resources. N,N- bis (2-ethylhexyl)acetamide (N523) is a newly developed extractant that presents good lithium extraction ability and selectivity. In this study, the kinetics and mechanism of lithium ion extraction with N523 in kerosene at 298.15 K were investigated using the rising single drop method. Results showed that the extraction process is controlled by diffusion and that the chemical reaction occurs at the interfacial area.

A novel setup for containment-free time-resolved experiments at a free-hanging drop is reported. Within a dead-time of 100 ms a drop of mixed reactant solutions is formed and the time evolution of a reaction can be followed from thereon by various techniques. As an example, a small-angle X-ray scattering study on the formation mechanism of EDTA-stabilized CdS both at a synchrotron and a laboratory X-ray source is presented here. While the evolution can be followed with one drop only at a synchrotron source, a stroboscopic mode with many drops is preferable for the laboratory source.

This paper reports experimental values of the surface tension between CO2 gas and tetra-n-butylammonium bromide (TBAB) aqueous solution measured by the pendant drop method. The experimental conditions were pressures from 1.00 MPa to 4.00 MPa, temperatures from 288.15 K to 303.15 K and wTBAB from 0.10 to 0.40, where wTBAB denotes the mass fraction of TBAB in the aqueous solution. These pressure–temperature-composition conditions partially fall into the stability zone of (CO2 + TBAB) semiclathrate hydrate but all data were obtained without any hydrate in the system. Surface tension decreased with increasing wTBAB and pressure but temperature dependency was not observed. Compared to the air–TBAB aqueous solution system and CO2–water system, the values of the surface tension were smaller.

The surface tension and the density of the Sn1−xBix system with Bi concentrations of 5, 10, and 15 at% have been studied using the lying drop method in a temperature interval of 470–800 K and under a vacuum of 10 Pa. The DROP program is used to obtain experimental values of the studied physical quantities. The addition of bismuth to tin was found to decrease the surface energy of the Sn1−xBix melts. It is also shown that there are linear temperature dependences for the surface tension coefficient and the density of the studied system.

Interfacial properties of the (CH4 + CO2 + H2O) system are of great importance in many geotechnical engineering applications. In this study, we report the first experimental measurements of the interfacial tensions in the (CH4 + CO2 + H2O) system under both three-phase (VLLE) and biphasic conditions. The measurements were made by the pendant drop method. The compositions of the coexisting phases were obtained from a previous study of the phase behavior and the phase densities were then calculated from an equation of state. IFTs along five isotherms in the VLLE region and along six isotherms in biphasic region are reported. In the VLLE region, the IFT between the water-rich liquid and the gas phase varied between (33 and 39) mN·m−1, with a sharp increase as the pressure increased along an isotherm towards the upper critical end point. In the same region, the IFT between the water-rich and CO2-rich liquids varied between (30 and 33) mN·m−1. The IFT between the gas phase and the CO2-rich liquid phase was too small to measure accurately but an approximate value was obtained which is consistent with Antonov's equality. In the biphasic region, measurements were made at temperatures up to 423 K and at pressures up to 30 MPa. As observed in other water-gas systems, the IFT declines monotonically along isotherms with increasing pressure and decreases with increasing temperature at constant pressure.

A floating drop method has the potential of high accurate interfacial tension measurement for liquid-liquid. In order to clarify its validity, the verification of the method should be carried out based on the liquid-liquid system where its interfacial tension is available. We measured the interfacial tension between water and liquid paraffin via a floating drop method by observing a clear submerged profile of heavier water droplet floating on lighter liquid paraffin. We then investigated the effect of the droplet size on the interfacial tension. Large droplets were found to improve the accuracy of the measured values, as demonstrated by a simulation based on the Laplace equation. The measured interfacial tension was 50.5 mN/m, which reasonably agrees with the values reported in the literature. We conclude that the floating drop method with a heavy droplet on a light liquid is effective for measuring the interfacial tension.