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The injection performance of a small volume of needle-free injection (up to 0.3 mL) has proven to be controllable and satisfactory in transdermal drug delivery. However, no comprehensive research on the behavior of larger volume injections with different requirements for clinical applications exists. This study aims to present the penetration characteristics of larger volume injections, including dynamic properties, dispersion pattern, and percent delivery. The researchers conduct impact and injection experiments with injection volumes from 0.1–1.0 mL, driving pressures of 0.5–1.75 MPa, and orifice diameters of 0.17–0.5 mm. This study uses high-speed photography and impact experiments to capture the dynamic properties of the liquid jet. The researchers observe the dispersion patterns of liquid penetration into the gels in the gel injection experiments and investigate the percentages of liquid delivered to the skin tissues in porcine tissues injection experiments. Moreover, this study uses the response surface methodology (RSM) to analyze the interactive effect between various injection parameters on the injection performance. Results describe the differences in penetration performance between larger volume injections and small volume injections, and the critical volume of the mentioned injections is approximately 0.6 mL.

The drying process of bitumen emulsion largely dominates the strength development of emulsion-based mixtures for pavement structure, thus it can be used to judge the quality of bitumen emulsion. However, the drying behaviour of bitumen emulsions was seldom considered. The emulsion drying and film formation theory are employed to study the drying process of different bitumen emulsions with a thin layer. Results indicated the drying process of bitumen emulsion can be divided into three stages: (a) an initial high evaporation rate stage; (b) an intermediate stage with a rapidly decreasing evaporation rate; (c) a final stage with a very small evaporation rate. The boundaries among the three stages can be identified by studying the water evaporation rate. Three drying parameters, i.e., the critical volume fractions of bitumen defining the boundaries among the three stages and the maximum packing fraction of bitumen droplets, are proposed to quantitatively characterize the drying behavior of bitumen emulsion. High values of these parameters indicate a bitumen emulsion that has rapid drying behavior. Therefore, these parameters are independent of the emulsifier type, but they are highly dependent on the bitumen’s droplet size. These drying parameters increase with a decrease in bitumen droplet size. Therefore, bitumen emulsion with a smaller size distribution of bitumen droplets can have a more rapid drying behavior, which is recommended in real engineering.

Space-arranged arrays of pits on Si(001) substrates were prepared using electron-beam lithography and plasma chemical etching. The positions of pits were arrange to the square and hexagonal lattices with a varying spacing. It was shown that the location of three-dimensional (3D) Ge nanoislands subsequently grown on the pit-patterned Si substrates depends on spacing for the both lattice types. In the case of the small spacing Ge nanoislands are located mainly inside the pits, while for the larger inter-pit distance the groups of Ge nanoislands at the pit periphery is also observed. This effect is interpreted in terms of critical volume for the 3D island nucleation which is achieved at the pit periphery with the increase of Ge amount deposited per pit. The effect of nanoisland growth, first inside the pits, then at their periphery was reproduced by Monte Carlo simulations of Ge growth on the pit-patterned Si substrates.

Background Recurrence is one of the concerns even after successful endovascular treatment of intracranial aneurysms. We sought to determine the critical aneurysm volume and risk factors related to aneurysmal stability in patients undergoing coil embolization of intracranial aneurysms. Methods Aneurysm volume and follow-up imaging data were retrieved in 3042 patients with 3530 aneurysms who were treated with endovascular coil embolization from January 2006 to October 2016. We analyzed the anatomic outcome in relation to aneurysm volume and determined the critical aneurysm volume favoring coil embolization. Results Recanalization rates were 2.8%, 6.3%, 19.4%, and 67.4% in each group with aneurysm volume of 1000 mm3, respectively. When we investigated the 100–1000 mm3 group, the recanalization rate remarkably increased at 500 mm3 (16.4% vs. 57.5%, P 500 mm3 (7.2% vs. 62.9%, respectively; P 500 mm3, the location was a significant prognostic factor for long-term stability (posterior circulation vs. anterior circulation; OR, 4.737; 95% CI, 1.275–17.602; P = 0.020). Conclusions In our series of cerebral aneurysms treated with coil embolization, 500 mm3 was found to be the critical volume determining stability after coil embolization. Large volume aneurysms in the posterior circulation were especially prone to recanalization after coiling.

Energy & Eco-Sustainability using Pressureless Silver Sintering for RF Power Electronics A virtually void free die attach was successfully achieved using a fixed but critical volume of Ag sinter paste by a process of pressureless sintering on a multi-axis cartesian style bonder, retro-fitted with with a high-speed jetting dispenser. While this process potentially offered an ideal combination of cost-effectiveness, control and speed, it required the development of additional software protocols to secure the level of performance demanded of the dispenser to meet exacting technical requirements. This proprietary adaptation we term “Fixed BLT” software, and over five test pieces we were consistently able to deliver a fixed height bond-line of circa 70% of bond height, translating as 50 um before sinter and 30 um after. In each case the result was a virtually bond free void secured in a timely, repeatable, commercially effective manner. The absence of voids was verified through industry standard non-destructive analysis utilizing confocal scanning acoustic microscopy (CSAM).

The causal relationship between the location of the largest discovered hydrocarbon deposits (about 1000) and the lithosphere thickness in the regions of the Earth crust is shown. Only the significant amount of facts may be considered as the arguments of uniqueness of the existence of deep zones of hydrocarbon generation on planetary rheological in nature, lithospheric-asthenospheric boundary followed by catastrophic break in the lithosphere. In the framework of the proposed model, the next migration process can be both sequential and abrupt. The model is based on the well-known physical formula transformed into a geodynamic expression that describes a natural process of hydraulic fracturing of the lithosphere crystalline rocks when the plume achieves the critical volume. It seems that the process of accumulation of matter in the plume and its evacuation interacts and goes parallel to the earthquake activity.

In this work, pendant droplets of different liquids (i.e. water, ethylene glycol, methanol, and acetone) on a plain aluminum surface and a three-stripe patterned surface were simulated using the Surface Evolver (SE) software. The critical droplet volume before detachment from a surface and droplet properties such as diameter, height, and surface energy were measured. Surface Evolver is a program that models liquid surfaces shaped by different forces and constraints. The program works by modifying a surface toward minimal thermodynamic energy by a gradient descent method. The initial input to Surface Evolver is a script file containing all the pertinent information about the droplet to be simulated including the gravitational constant, volume, density, and contact angle. For these simulations, the gravitational constant was set to -1 for all liquids (i.e. 9.81 m s-2), and the values of density and contact angle were based on the simulated liquid type. As part of this study, droplet contact angles were measured on an aluminum surface at room temperature (~20°C), and these values were used as inputs in the simulation. The measured static contact angle for water, ethylene glycol, methanol, and acetone were found to be 88.2 ,°61.0 ,°20.9°, and 13.0°, respectively. For each simulation, more than 100 iterations were performed before the droplet geometry converged and was ready for measurement. The surface energy was taken directly after each iteration, while the droplet height and diameter were calculated from simulation pictures using a pixel counting method. The critical pendant droplet volumes for water, ethylene glycol, methanol, and acetone on a plain aluminum surface were found to be 17.9, 21, 19.03, and 14 μL, respectively. For the purposes of this study, the critical volume (i.e. when the droplet starts detaching) was defined when the surface energy was found to be in the range of -0.15 J to 0.15 J. Besides critical volumes, droplet data associated with smaller volumes (i.e. 5, 8, 10, 12, and 15 μL) were also measured and compared among liquids. Patterned surfaces were also studied in this work. These surfaces consisted of a central hydrophilic stripe varying from 1 mm to 5 mm in width sandwiched between two outer hydrophobic regions. Critical droplet volumes on these surfaces are also discussed.

The sustainable management of lakes and reservoirs requires the determination of their minimum environmental water level. Even though the assessment of minimum water level depends on a number of biotic and abiotic factors of the lake ecosystem, in many cases these factors are not entirely known and, furthermore, their evaluation is usually a challenging and laborious task. On the other hand, the lakes/reservoirs may comprise an important water resource to meet the requirements arising from economic activities. In this paper, the morphological and hydrological features of four lakes of northern Greece were analysed in order to assess their minimum environmental water level. The hydromorphological analysis was based on the relationship of the lake surface area and volume with water level as well as the water inflow from the lake&rsquo, s hydrological catchment area, considering as the lake&rsquo, s critical volume storage, the annual water volume flowing into a lake from its hydrological catchment area with a probability of exceedance 50% of a long time series of hydrological years. By combining morphological and hydrological features, the proposed methodology aimed to extend the analysis based solely on morphological features, and assess more comprehensively the minimum environmental water level in the four lakes, ensuring also the rising from the minimum level to the maximum (overflow) level for most of the hydrological years.

Background: This study is aimed to find a critical volume of operated giant or massive extradural hematoma (EDH) that affects outcome significantly and analyze them with respect to their clinical, surgical, and outcome perspective. Methods: This retrospective study includes 253 patients operated for EDH in emergency in the Department of Neurosurgery of IMS BHU, Varanasi, India, a tertiary care center, between August 1, 2018, and November 1, 2019. Giant EDH critical volume was evaluated. Twenty-nine patients with giant EDH with clot volume ≥ 80 ml were further analyzed for clinical, surgical, and outcome predictive factors. Statistical analysis was done using Prism GraphPad ver. 8.0.0. P value was taken at 0.05. Results: Dichotomized group analysis with Glasgow Outcome Score (GOS) 4–5 versus GOS 1–3 for testing clot volume revealed significance difference with P < 0.001. Mean volume of GOS 1–3 came out to be 79.68 ml. Hence, we took clot volume >80 ml for further analysis. The most common age group was 20–40 (55.17%). M2 (31.03%) was the most common best motor response in operated giant EDH cases. Most of them were having severe (79.31%) head injury. Glasgow Coma Scale (GCS) at admission (P < 0.0001), pupillary changes (P = 0.0032), and best motor response (P < 0.0001) was significantly (P < 0.05) associated with outcome following surgery for giant EDH. Conclusion: Giant EDH with volume ≥ 80 ml is associated with poorer outcome. GCS at admission, pupillary changes, and best motor response is predictors for surgical outcome of giant EDH.

Simultaneous description of critical point, vapor pressure and liquid density with an equation of state has been a hot research topic. In this work, the possibilities and limitations of the Cubic Plus Association equation of state for describing these properties of associating fluids have been studied. First a procedure is developed to determine the energy and co-volume parameters by converting the system of three equations at the critical point to a single variable root-finding problem. The procedure is then used in parameter estimation to simultaneously match the critical temperature and pressure as well as fit the vapor pressure and liquid molar volume of typical associating fluids. The performance of the estimated parameters is subsequently compared with the parameters fitted only to vapor pressure and liquid molar volume. The possibility of introducing an extra adjustable parameter to improve the performance is further explored. The results show that, for the studied associating fluids, the Cubic Plus Association equation of state with the obtained parameters can match the critical temperature and pressure exactly, fit the vapor pressure within 2% and the liquid molar volume within 3–4% in the range of temperature up to 0.95 critical temperature, while the model overpredicts the critical volume up to 18%.

In order to simplify the demulsification speed test of emulsified asphalt, rapid-breaking, medium-breaking and slow-breaking emulsified asphalt as well as different aggregates were selected for the demulsification speed test. The specific surface area of each single grade was determined by the actual measurement, and the equivalent aggregate was collected according to the principle of equivalent surface area. The results show that the equivalent aggregate can be composed by the assembling of gradations smaller than 0.075mm and one or two bigger gradations. Therefore, the types of gradation in the equivalent aggregate will be reduced by one-half compared with that in the standard aggregate. The surface area of the equivalent aggregate is the same as that of the standard aggregate, and under a certain volume ratio, the demulsification rate determined by equivalent aggregate or standard aggregate is the same.There is also a critical volume ratio existing for the equivalent aggregate, If the critical volume ratio is exceeded, the demulsification rate determined by the equivalent aggregate will be greatly different from that determined by the standard aggregate. It is also found that the volume ratio turns to 1 without any changes when the proportion of gradation smaller than 0.075mm reaches 25%-30%.

In this study, experiments were conducted to investigate the liquid drop spreading behavior on the grooved surface. The critical volume and the critical angle at which the water drop started to spread on the grooved surfaces were determined by the shadow method. It was found that the drop spreading on the grooved surface is a catastrophe process and the critical values vary with the groove structures. A thermodynamic method was proposed for predicting the critical drop volume spreading on the grooved surfaces with different structures. The consistency between the theoretical and experimental results is concluded to be satisfactory.

Experimentally determined critical temperatures (Tc) and critical pressures (Pc) are reported for 64 compounds. In addition, the critical volume (Vc) has been experimentally determined for 14 of these compounds. The compounds in this study are of industrial interest in process design, simulation, and safety. These data also extend our understanding of and ability to predict these properties from group contribution methods.

The irradiation hardening of Ni-Mo-Cr and Ni-W-Cr alloy was investigated. 7 MeV Xe26+ ion irradiation was performed at room temperature and 650 °C with peak damage dose from 0.05 to 10 dpa. With the increase of damage dose, the hardness of Ni-Mo-Cr and Ni-W-Cr alloy increases, and reaches saturation at damage dose ≥1 dpa. Moreover, the damage dose dependence of hardness in both alloys can be described by the Makin and Minter’s equation, where the effective critical volume of obstacles can be used to represent irradiation hardening resistance of the alloys. Our results also show that Ni-W-Cr alloy has better irradiation hardening resistance than Ni-Mo-Cr alloy. This is ascribed to the fact that the W, instead of Mo in the alloy, can suppress the formation of defects under ion irradiation.

In this work, a trainable feed-forward back-propagation network was developed by employing the Levenberg-Marquardt training algorithm to predict the surface tension of binary refrigerant mixtures. 1260 experimental data were collected from reliable literature to train and test the network. Temperature, critical pressure, critical temperature, critical volume and acentric factor of the binary mixtures were selected as input variables of the proposed network. The optimum number of hidden layers was determined to be 1, with 19 neurons in the hidden layer. Tan−sigmoid and purelin functions was chosen as the transfer functions in the hidden and output layers, respectively. The results revealed that the ANN has the capability to correlate and estimate the surface tension accurately with an overall %AARD and correlation coefficient values of 0.7582 and 0.9997, respectively. In addition, the results were compared to different well-known correlations and models which indicated a better performance of the developed ANN.

Asphalt mastic, composed of asphalt and filler, is an important part of asphalt mixture. The interaction between asphalt and filler, called asphalt-filler interaction, directly affects the performance of asphalt mastic and asphalt mixture, because composite materials are more likely to be damaged from the interface. However, how to accurately and effectively measure or evaluate the asphalt-filler interaction has always been an important issue that has not been solved in the field of pavement materials. For better understanding and improving asphalt-filler interaction, this paper reviews existing research on asphalt-filler interaction, including asphalt-filler interaction models and mechanisms, the critical volume of filler in mastic, evaluation methods of asphalt-filler interaction, and influencing factors. From the numerous literature it can be concluded that 1) asphalt-filler interaction is a very complex physicochemical interaction, and current theories cannot fully explain the interaction process; 2) there are five main methods for evaluating asphalt-filler interaction, namely rheological theory, adsorbed asphalt film thickness, surface free energy, atomic force microscopy and molecular dynamics simulation; 3) the main factors influencing the asphalt-filler interaction are the properties of asphalt and filler, as well as external conditions such as temperature, load, and moisture. Besides, the achievements including advantages and disadvantages of each branch have been discussed in different sections, and some improvements are proposed to deepen the mechanism and evaluation methods of asphalt-filler interaction, thus provide references for improving the service life of the asphalt pavement.

Relationships of volumes during thermal expansion of metals are analyzed. It is demonstrated that metals with BCC structure undergo two-step structural change at the melting point: at the beginning the BCC structure is transformed into FCC structure and then clusters are formed with K = 12 and statistical packing of atoms of the liquid phase. Before melting, hexagonal layer-by-layer (6 + 6) packed Cd and Zn change their structure from K = 6 to K = 8. Metals with FCC structure do not change the number of neighbors before melting, forming clusters with K = 12. It is shown that conditions of pre-melting and polymorphic FCC (HDP) → BCC transformations are reached for the critical volume of thermal expansion caused by leveling of fluctuations of atom and electron densities.

One of the most important properties of ionic liquids (ILs) is their densities. Accurate knowledge of this property is required in engineering and scientific purposes including equipment design, liquid metering calculations, and other applications. As a result, it is important to develop accurate and effective models for prediction of this property. The present work aims to develop a model based on Gene Expression Programming (GEP) technique for prediction of experimental density values of 146 different ionic liquids at different temperatures. A databank containing 602 data gathered from the literature was utilized to develop the model. The input parameters of the model are temperature, molecular weight of IL, normal boiling point temperature of IL, critical pressure of IL, critical volume of IL, and acentric factor of IL. The outcomes of this work indicate that the developed model is capable of estimating target density data with an acceptable accuracy. The effectiveness and accuracy of the model were checked by utilizing different statistical and graphical techniques. Moreover, results of the proposed model are compared with predictions of literature correlations and it is shown that the GEP model is effectively superior to other correlations and exhibits higher accuracy and reliability.