We present a surface-mountable miniature Fabry-Perot (FP) pressure sensor that utilizes the total internal reflection at a 45 degrees angled fiber end face to steer the optical axis by 90 degrees . By using the fiber as a waveguide, as well as a natural mask in photolithography, an FP cavity ...

Air sparging (AS) is one of the most efficient techniques for remediating saturated soils and groundwater contaminated with volatile organic compounds. A series of physical modeling tests for different sizes of porous media under varied injection pressure were conducted to investigate the effect of particle size and air injection pressure ...

To select the best available packing material for malodorous organic gases such as toluene and benzene, biofilter performance was compared in biofilters employed different packing materials including porous ceramic (celite), Jeju scoria (lava), a mixture of granular activated carbon (GAC) and celite (GAC/celite), and cubic polyurethane foam (PU). A toluene-degrading ...

A wafer scale bulge testing system has been constructed to study the mechanical properties of thin films and microstructures. The custom built test stage was coupled with a pressure regulation system and optical profilometer which gives high accuracy three-dimensional topographic images collected on the time scale of seconds. Membrane deflection ...

The rapid separation of mixtures of six peptides using porous polymer monolithic layers in electrophoresis and pressurized planar electrochromatography modes has been achieved. The separations in the former mode were performed on a generic hydrophobic poly(butyl methacrylate-co-ethylene dimethacrylate) layer with no ionizable functionalities and required 2 min. This layer also ...

Long-circulating and pH-sensitive liposomes, containing cisplatin (SpHL-CDDP), have been developed as an alternative aimed at avoiding severe side effects as well as the appearance of resistance, which can limit the use of free cisplatin. However, physical (i.e., aggregation/fusion) and chemical instabilities limit the use of these drug carriers as pharmaceutical ...

Intrapulse quantum cascade laser spectrometers are able to produce both saturation and molecular alignment of the gas sample. This is due to the rapid sweep of the radiation through the absorption features. The intrapulse time domain spectra closely resemble those recorded in coherent optical nutation experiments. In the present paper, ...

Monte Carlo simulations in the constant voltage ensemble were performed for electrolytes in porous electrodes. It was found that the electrical and mechanical properties in porous electrodes dramatically change depending on the pore size and the dielectric constant of the medium. For a low dielectric constant of the medium, the ...

Steam explosion, one potential commercial pretreatment method for lignocellulosic wastes, was used to improve methane production of bulrush. Steam exploded bulrush showed a higher methane yield than the raw sample. The effects of steam pressure, moisture content and residence time on the concentration of neutral detergent fiber (NDF) and methane ...

The most favored model of humidity transduction views the cuticular wall of insect hygroreceptive sensilla as a hygromechanical transducer. Hygroscopic swelling or shrinking alters the geometry of the wall, deforming the dendritic membranes of the moist and dry cells. The small size the sensilla and their position surrounded by elevated ...

This paper describes a method developed for quantification of gas emissions from the leachate collection system at landfills and present emission data measured at two Danish landfills with no landfill gas collection systems in place: Fakse landfill and AV Miljø. Landfill top covers are often designed to prevent infiltration of ...

Evidence is presented to show the microstructural anisotropy responsible for normal stress in sheared suspensions. Particle velocimetry is combined with three-dimensional particle locations obtained via confocal microscopy at rest. A range of volume fractions phi and local shear rates gamma are investigated in a weakly Brownian pressure-driven suspension. At high ...

We propose an automated needle hydrophone-based scanning system to measure high-resolution 3-D acoustic pressure distributions generated by high-intensity focused ultrasound (HIFU). The hardware consists of a host computer, subsystems for HIFU generation, and an oscilloscope to sample the pressure response from a sensor in a water tank. Software was developed ...

Large scale production of graphene nanosheets was achieved by arc evaporation of a graphite rod in air. The graphene nanosheets are approximately 100-200 nm wide and the number of layers is mainly in the range of 2-10. Several tens of grams of product were obtained per day. The yield of ...

The aim of this study was to investigate the use of surgical smoke-producing procedures such as laser ablation or electrosurgery in minimally invasive microendoscopic procedures. This study proposes a technical solution to efficiently remove surgical smoke from very small endoscopic cavities using microports as small as 20 G (0.9 mm) ...

Evaporation of motionless, levitating droplets of pure, low-volatility liquids was studied with interferometric methods. Experiments were conducted on charged droplets in the electrodynamic trap in nitrogen at atmospheric pressure at 298 K. Mono-, di-, tri-, and tetra(ethylene glycols) and 1,3-dimethyl-2-imidazolidinone were studied. The influence of minute impurities (<0.1%) upon the ...

Hydroxycamptothecin is a promising anticancer agent that possesses the ability to inhibit the growth of a wide range of human tumors. Owing to its poor solubility and instability, the pharmaceutical development and clinical utilization of hydroxycamptothecin have been limited. In the present study, a novel precipitation-combined high-pressure homogenization (PCH) technique ...

A novel MSW shredder was presented but many aspects of the shredder have not been fully characterized. The feed moisture is an important factor that influences crushing performance. This paper focuses on the effect of feed moisture. The breakage of municipal solid waste (MSW) at several moisture levels (0%, 10%, ...

The in vivo cavitation response associated with blood-brain barrier (BBB) opening as induced by transcranial focused ultrasound (FUS) and microbubbles was studied in order to better identify the underlying mechanism. A cylindrically focused hydrophone, confocal with the FUS transducer, was used as a passive cavitation detector (PCD) to identify the ...

The creation of a bubble in a liquid is energetically favorable when the liquid is subject to a netan overall tension less than of its saturated vapor pressure. This gain is offset by the creation of a liquid-vaporgas interface, and only bubbles larger than some critical size will spontaneously grow. ...

It has been shown experimentally that the optical breakdown strength of water is a pressure dependent quantity, growing with increasing pressure. The dependence of the breakdown strength on temperature and dissolved gas concentration over a larger range of pressures will be observed. Using a custom fabricated pressure vessel and high-power ...

We used a capacitive technique to determine the radial clearance between the piston and cylinder of a gas piston gauge. This method determines the effective area of a piston gauge pressure standard, independent of calibration against another piston gauge or manometer, as long as the diameter of the piston is ...

A method for the direct measurement of the pressure sensitivity of a microelectromechanical system (MEMS) microphone is developed for frequencies from 10 to 100 kHz. The use of a simultaneous pressure field measurement reduces the errors in calculating the pressure sensitivity from free field measurements, and it allows calibration of ...

Designing quality into dosage forms should not be only based on qualitative or purely heuristic relations. A knowledge space must be generated, in which at least some mechanistic understanding is included. This is of particular interest for critical dosage form parameters like the strength of tablets. In line with this ...

Computer simulations are performed to measure the disjoining pressure profile Pi(y) across the three-phase contact line formed by a liquid-vapor interface intersecting a planar substrate wall lying in the xy plane. The method makes use of an exact expression for the disjoining pressure in terms of the density profile and ...

A pressure and flow sensor based on the electrothermal-thermistor effect of a batch-processed carbon nanotube wall (CNT wall) is presented. The negative temperature coefficient of resistance (TCR) of CNTs and the temperature dependent tunneling rate through the CNT/silicon junction enable vacuum pressure and flow velocity sensing because the heat transfer ...

This paper deals with the influence of gas law on ultrasonic behaviour of porous media when the saturating fluid is high pressured. Previous works have demonstrated that ultrasonic transmission through a porous sample with variations of the static pressure (up to 18 bars) of the saturating fluid allows the characterization ...

Here we show that transient flow of Newtonian fluids in viscoelastic PDMS microfluidic channels can be described by a diffusive pressure spreading mechanism analogous to the electric telegrapher's equation. The pressure diffusion constant D(p) = 1/R(x)C(x) of a channel with length l is determined by the hydrodynamic resistance R(x) and ...

A new method is presented to measure capillarity-induced negative pressure. Negative pressures of several bars have been measured for five different liquids (ethanol, acetone, cyclohexane, aniline, and water) over a range of surface tension. Capillary negative pressure was measured in 79 +/- 3 nm silica nanochannels on the basis of ...

This work combines modeling and experiment to assess encapsulated microbubble oscillations associated with broadband pressure peaks detected after microbubble excitation (postexcitation signals). Data were acquired from albumin-shelled and phospholipid-shelled microbubbles using a passive cavitation detector consisting of a confocally aligned 2.8-MHz transmitter and 13-MHz receiver. Microbubbles in weak solutions were ...

A new method is reported on how to measure the local pressure amplitude and the Q factor of ultrasound resonances in microfluidic chips designed for acoustophoresis of particle suspensions. The method relies on tracking individual polystyrene tracer microbeads in straight water-filled silicon/glass microchannels. The system is actuated by a PZT ...

This work proposed to study the influence of varying compaction pressure on the plastic energy, elasticity (Young's modulus), particle yield strength, strain hardening, and applied pressures on derived Heckel parameter using material with different densification and deformation mechanisms: ibuprofen (IBN), paracetamol (PCM) (elastic behavior), methyl cellulose (Me-Cel), microcrystalline cellulose (MCC), ...

This paper presents the concentration distribution around a growing nitrogen gas bubble in the blood and other tissues of divers who surface too quickly, when the ambient pressure through the decompression process is variable and constant. This effort is a modification of Sirinivasan et al. model (1999) [9]. The mathematical ...

The Dubinin-Astakhov and Dubinin-Radushkevich isotherms, originally formulated from the classical volume filling theory of micropores, constitute the most accepted models for describing gas adsorption in microporous materials. The most important weakness of these equations relies on the fact that they do not reduce to Henry's law at low pressures, not ...

Homogeneous nucleation rates of the n-alkanes (C(i)H(2i+2); i=7-10) were determined by combining information from pressure trace measurements and small angle x-ray scattering (SAXS) experiments in a supersonic Laval nozzle. The condensible vapor pressure p(J max), the temperature T(J max), the characteristic time Deltat(J max), and supersaturation S(J max) corresponding to ...

We present an experimental investigation of the dependence of the production of large methane clusters on the cluster source conditions. The clusters were produced at room temperature through supersonic expansion of methane gas at the backing pressures P(0) ranging from 10 to 84 bar using five conical nozzles of different ...

Four coals of different rank were gasified, using a steam/oxygen mixture as gasifying agent, at atmospheric and elevated pressure in a fixed bed reactor fitted with a solids feeding system in continuous mode. Independently of coal rank, an increase in gasification pressure led to a decrease in H(2) + CO ...

We analytically investigate the prospect of using electrokinetic phenomena to transfer hydrostatic energy to electrical power with high energy transfer efficiencies, by exploiting time periodic pressure-driven flows in narrow fluidic confinements. An expression for the energy transfer efficiency for such pulsating pressure-driven flows is derived by considering wall-slip effects due ...

This paper describes a technique for rapidly exchanging the solution environment near a surface by displacing laminar flow fluid streams using sudden changes in applied pressure. The method employs off-chip solenoid valves to induce pressure changes, which is important in keeping the microfluidic design simple and the operation of the ...

In recent years, it has become increasingly interesting to understand the performance of mass spectrometers at pressures much higher than those employed with conventional operating conditions. This interest has been driven by several influences, including demand for the development of reduced-power miniature mass spectrometers, desire for improved ion transfer into ...

The aim of our study was to analyse the relationships between hypertension, HSP60, oxidative stress, lipid profile and cardiometabolic risk in 126 females with arterial hypertension (AHW) and 39 normotensive females (AH-). Females with AH+ were significantly older and more frequently suffered from ischemic heart disease, angina pectoris, prior MI, ...

The aim of our study was to investigate blood pressure (BP) levels and their association with different indices of body fat in adult Baniyas. A cross-sectional survey was carried out on an endogamous group of 577 adults (307 females and 270 males) aged 25-60 years in Delhi, India. Data were ...

Poly(dimethylsiloxane) or PDMS is an excellent material for replica molding, widely used in microfluidics research. Its low elastic modulus, or high deformability, assists its release from challenging molds, such as those with high feature density, high aspect ratios, and even negative sidewalls. However, owing to the same properties, PDMS-based microfluidic ...

A quantitative comparison of the benthic distribution in the Middle and Southern Caspian Sea, using benthos distribution maps with previously published materials, showed that the benthic communities is stable and interrupted only by the introduction of new species. The bottom community is dominated by small-size organisms, mainly fry and young ...

The objective of directional acoustic sensors is to provide high directivity while occupying a small amount of space. An idealized point sensor achieves this objective from a knowledge of the spatial partial derivatives of acoustic pressure at a point in space. Direct measurement of these derivatives is difficult in practice. ...

Biodiverse coastal zones are often areas of intense fishing pressure due to the high relative density of fishing capacity in these nearshore regions. Although overcapacity is one of the central challenges to fisheries sustainability in coastal zones, accurate estimates of fishing pressure in coastal zones are limited, hampering the assessment ...

The effect of an electrical double layer (EDL) on microchannel flow has been studied widely, and a constant bulk electric conductivity is often used in calculations of flow rate or pressure drop. In our experimental study of pressure-driven micropipette flows, the pipette diameter is on the same order of magnitude ...

We have used molecular dynamics simulations with coarse-grained and atomistic models to study the lateral pressure profiles in lipid monolayers. We first consider simple oillair and oil/water interfaces, and then proceed to lipid monolayers at air/water and oil/water interfaces. The results are qualitatively similar in both atomistic and coarse-grained models. ...

Hydrodynamic induced cavitation generates imploding cavitation bubbles which can lead to degradation or even mineralisation of water constituents without addition of any chemicals. This technology overcomes the problems of ultrasound irradiation by the local production of a cavitation cloud close to the sonotrodes. Hydrodynamic cavitation can be stabilised downstream of ...

The atmospheric oxidation of monoterpenes plays a central role in the formation of secondary organic aerosols (SOAs), which have important effects on the weather and climate. However, models of SOA formation have large uncertainties. One reason for this is that SOA formation depends directly on the vapor pressures of the ...