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Shiitake (Lentinula edodes) cultivation in sawdust media consisting of kunugi (Quercus acutissima) mixed with sugi (Cryptomeria japonica): optimization of gaseous phase rate in media by three-phase-structure analysis

Shiitake (Lentinula edodes) cultivation in sawdust media consisting of kunugi (Quercus acutissima) mixed with sugi (Cryptomeria japonica): optimization of gaseous phase rate in media by three-phase-structure analysis

Abstract The effects of the gaseous phase rate of kunugi (Quercus acutissima) sawdust media mixed with sugi (Cryptomeria japonica) determined by a three-phase- structure analysis of the fruiting body yields of shiitake were investigated. The fruiting body yield on kunugi media was significantly lower than that on commercially available hardwood-sawdust-mixture (HSM) media with 64 % water content. Three-phase-structure analysis showed that the gaseous phase rate in kunugi media was lower than that in HSM media. When the gaseous phase rate in kunugi media was increased to the level in HSM media by decreasing the water content to 56 %, the fruiting body yield on kunugi media also increased. These results suggested that kunugi sawdust could be used for shiitake cultivation if the gas- eous phase rate in the media was optimized. Because sugi has a lower specific gravity and higher porosity than kunugi, mixing sugi sawdust up to 30 % with kunugi media caused an increase in the gaseous phase rate, and the fruiting body yield reached the same level as that in HSM media. These results suggested that kunugi media could be used for shiitake cultivation by mixing with sugi sawdust.

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Measurements for Electric Dipole of Selected Clusters Scn C60 in Gaseous Phase

Measurements for Electric Dipole of Selected Clusters Scn C60 in Gaseous Phase

Measurement of electric dipole moment is an excellent probe of structure and dynamics of molecules since it is directly related to the geometry and charge transfer in compounds [2] [3]. In literature, we find many detailed results and experiments on molecules and their electronic optical proprieties in solution with a solvent [4] [5] [6]. Few results are available on systems in gas phase at their fundamental states. Naturally, experiments in vacuum for isolated mole- cules lead to a better information about systems and their fundamental proprie- ties. Moreover, the effect of solvent on molecules should be included in the cal- culation [7] by considering any model which is relatively a hard task, thus calcu- lation in gas phase is more practical if we are intended to compare experimental results to theoretical ones. The molecular beam deflection technique is a power- ful experimental method that is used for many years [8] [9] [10] [11] in order to measure magnetic and electric dipole of molecules in gas phase. This method is inspired from the famous Stern-Gerlach [1] experiment (where an inhomoge- How to cite this paper: Abd El Rahim, M.,

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Modeling of aqueous foam blast wave attenuation

Modeling of aqueous foam blast wave attenuation

From the numerical point of view, the post-shock total energy can be estimated via linearized Riemann invariants and can be shown to decrease with an increase of the acoustic impedance of the confining medium. This energy radiates spherically, and will result in a lower overpressure. Moreover, a two-phase shock is a composite shock, which consists of a shock wave followed by a relaxation zone. The spherical rarefaction will thus tend to smooth the peak overpressure. In addition, the compress- ibility of the two-phase confinement is mainly driven by the gaseous phase. The liquid phase tends to store the kinetic energy given by the spherical shock wave. Decreasing the temperature of the gas will also decrease the level of the overpressure.

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Modelling and Simulation of the Hydrodynamics and Mixing Profiles in the Human Proximal Colon Using Discrete Multiphysics

Modelling and Simulation of the Hydrodynamics and Mixing Profiles in the Human Proximal Colon Using Discrete Multiphysics

For the evaluation of the influence of a gaseous phase we used the partially-filled model and added SPH particles, representing the gas. The pressure of the gaseous phase in the colon is not well known. According to Kurbel et al. [16], the total gas pressure due to bubble formation in the colon is at atmospheric pressure or slightly above. In the model, we assume a gauge pressure of 60 Pa. Chemically, the model assumes that the gas phase is comparable to dry air and follows the ideal gas equation of state: technically speaking this is not true, but given the small gauge pressure, we assume that this is an acceptable simplification. Gravitational acceleration in the y-direction is also added to all particles.

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An evolutionary solution of terrestrial isopods to cope with low atmospheric oxygen levels

An evolutionary solution of terrestrial isopods to cope with low atmospheric oxygen levels

With respect to the two constituent phases of marsupial development of present-day terrestrial isopods, we found that oxygen limitations occur during development of the progeny in the aqueous phase but not the gaseous phase within the motherly brood pouch. Under hypoxia, longer development in the initial aqueous conditions in the cold (Fig. 1B, Table 1) was followed by more rapid development in the subsequent gaseous phase at both temperatures (Fig. 1C, Table 1; Fig. S2). Given that oxygen limitation is expected to be greater under warm conditions, this result is of special interest in view of the capacity of brooding P. scaber females to supply oxygen to embryos under varying temperature conditions. Female isopods actively provide oxygen to their progeny only during the aqueous phase, through special structures called cotyledons within the marsupial cavity (Hoese and Janssen, 1989) that have evolved as a novel adaptation to terrestrial habitats (Csonka et al., 2013; Hornung, 2011). Females under conditions of low environmental oxygen and temperature may be limited in the supply of oxygen as a result of their slow metabolic rate and increased oxygen demand of the brood, and this might explain why progeny spent a proportionally longer time in the aqueous phase. Longer development in the aqueous phase may be necessary to achieve a state of development in preparation for subsequent development in gaseous conditions. This result suggests that the limits to oxygen

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The Influence of Various Solvents on Energetic Property and Stability in C5h4 Divalent Five-Membered Ring: A Dft Studies

The Influence of Various Solvents on Energetic Property and Stability in C5h4 Divalent Five-Membered Ring: A Dft Studies

By using density functional theory (DFT) in B3LYP/6-311++G(d, p) level of theory and conductor-like polarizable continuum modem (CPCM) we examined solvent effects on energy levels in C 5 H 4 for both singlet and triplet states. For this purpose, different solvents, such as gaseous and aqueous solvents, Diethyl ether, Nitro methane, DMSO, Acetonitrile, Methanol, Ethanol, Acetone, Dichloroethane, THF, Aniline, Chlorobenzene, Chloroform, diethyl ether, dichloromethane, toluene, benzene, CCl 4 , cyclohexane, and heptanes, were used Selectively. The findings suggest that selecting a different solvent changes level of energy, Electrophilicity, Chemical hardness, Chemical potential, and dipole moment for both singlet and triplet states, due to changes in aprotic or perotic properties of solvent. Based on the results, the most stable structure for C 5 H 4 is achieved when the solvent used for both singlet and triplet state is in gaseous phase while the lowest stability is observed when an aqueous solvent is employed for both singlet and triplet states.

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MULTICOMPONENT GAS-PARTICLE FLOW AND HEAT/MASS TRANSFER INDUCED BY A LOCALIZED LASER IRRADIATION ON A URETHANE-COATED STAINLESS STEEL SUBSTRATE

MULTICOMPONENT GAS-PARTICLE FLOW AND HEAT/MASS TRANSFER INDUCED BY A LOCALIZED LASER IRRADIATION ON A URETHANE-COATED STAINLESS STEEL SUBSTRATE

The change of gas velocity against laser power confirmed this conclusion, except the case with laser power of 2.5 kW. In order to reveal more detailed results, a close look at the interaction between ejected parcels and gaseous phase, four snapshots, which are at time of 1.00 s, 2.00 s, 2.12 s and 2.77 s, are provided in Fig. 9. It can be seen that parcels (white dots) are lifted by the surrounding air as shown in Fig. 9 (a). And the entire velocity field is found symmetric-like. Figure 9 (b) shows the similar phenomena, but with more parcels and higher velocity. However, asymmetric velocity appear in Fig. 9 (c) due to the momentum transfer between parcels and gaseous phase which is the leading factor of affecting the entire velocity field in simulation domain. In addition, from the perspective of momentum conservation, the momentum exchange will slow down the gas velocity and accelerate the parcels’ velocity if the drag force is larger than gravity. However, once the number of parcel is too huge, the momentum of gaseous phase will be completely drag down as a result of this intensive momentum exchange. In other words, the gas velocity will be pulled down toward the ground. The last snapshot, Fig. 9 (d) shows that the velocity at the zone that is close to the laser heating spot is directing to the ground. As a result, the parcels on the paint will be pulled to a place nearby as shown. A comparison between Fig. 9 (c) and (d) shows that the velocity does not have a significant increase during the period of 0.57s due to large number increase of parcels which certainly consume a large amount of momentum that hold by gaseous phase.

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Theoretical study of Bromine substituent effects in ortho-, meta- and para- positions of acetophenone on electronic - structural properties and IR spectrum via density functional theory

Theoretical study of Bromine substituent effects in ortho-, meta- and para- positions of acetophenone on electronic - structural properties and IR spectrum via density functional theory

length are slightly larger than the experimental values, due to the theoretical calculations belong to isolated molecules in gaseous phase and the experimental results belong to molecules in solid state[26],on the other side there is small difference between the optimized bond angles and bond length for acetophenone from its for bromoacetophenone isomers excepting that the nearest angles and bonds to Br substitute which are slightly larger than its in acetophenone may be due to the withdrawing effect for Br substitute .

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Ft-Ir, Ft-Raman and Computational Study of Phenylurea

Ft-Ir, Ft-Raman and Computational Study of Phenylurea

The IR and Raman spectra of the title compound have been recorded and analyzed. The harmonic vibrational wavenumbers were calculated theoretically using Gaussian09 software package. Wavenumbers were calculated at HF and DFT levels. The observed wavenumbers were found to be in agreement with the calculated (DFT) values. The small differences between experimental and calculated vibrational modes are observed. It must be due to the fact that experimental results belong to solid phase and theoretical calculations belong to gaseous phase. The first hyperpolarizability, infrared intensities and Raman activities are reported.

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A Study of Droplet Evaporation

A Study of Droplet Evaporation

Abstract: We investigate the problem of the vaporization of a liquid droplet in a hotter environment of the same fluid. The Navier-Stokes equations are solved for a physical model which assumes spherical symmetry and laminar conditions in the quasi steady case. The study is mainly characterized by the fact that the equation of conservation of momentum is effectively taken into account and the velocity of the drop is not always uniform. Recession laws which are different from the classical law can be derived from the zeroth order approximation solution. Additional assumptions on the thermodynamical properties of the gas phase in subcritical conditions restore the classical law and permit the determination of an analytic expression for the vaporization ratio K. The analysis of the evolution of the temperature, the density and the velocity in the droplet and in the gaseous phase reveals the existence of shock waves which develop from the center of the droplet towards its boundary and an unbalanced energetic layer attached to the interface when the velocity is not uniform in the drop.

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Explicit modeling of volatile organic compounds partitioning in the atmospheric aqueous phase

Explicit modeling of volatile organic compounds partitioning in the atmospheric aqueous phase

Two dimensional frameworks have been recently proposed to examine the formation and aging of secondary organic aerosols during atmospheric oxidation of hydrocarbons (e.g. Jimenez et al., 2009; Pankow and Barsanti, 2009; Barsanti et al., 2011; Kroll et al., 2011). These frameworks attempt to capture the oxidative trajectories in a space defined by the volatility of the secondary species and their oxidation degree (e.g. Donahue et al., 2011, 2012). A similar two dimensional frameworks is used here to explore the oxidative trajectories in the context of a gas/aqueous multiphase system. We define the first dimension by the Henry’s law coefficient H , used as a metric to represent the water solubility of the species. With L = 3 × 10 −7 , a species is equally distributed in the two phases (ξ = 0.5) for H = 1.45 × 10 5 M atm −1 (see Eq. 1). Species having H less than 1.45 × 10 3 M atm −1 will there- fore almost exclusively be found in the gas phase (ξ < 0.01), while species with H greater than 1.45 × 10 7 M atm −1 will almost exclusively be found in the aqueous phase (ξ > 0.99). We use the mean carbon oxidation (OS C ) as the second di-

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Ultrasonic and Cooling Approaches for Reinforcement of the Microextraction Methods

Ultrasonic and Cooling Approaches for Reinforcement of the Microextraction Methods

The gas flow headspace LPME (GF-HS-LPME) procedure was introduced by Yang et al. [113], to improve the efficiency of HS-LPME. In comparison with HS-LPME, it is faster, more economical and more efficient for volatiles due to increasing the analyte molecules in the gas phase. Despite the foregoing advantages, it has some limitations in its routine applications, such as low recovery for low- volatiles, operational difficulties due to easy driving out of the microdroplet and incomplete quantitative extraction. To overcome these drawbacks, the first effort resulted in a novel gas purge microextraction setup, which was named gas purge microsyringe extraction (GP-MSE) system [114]. A 100-µl microsyringe barrel was used as the “holder” and “protector” of the extracting organic solvent and a narrow stainless steel tube was fitted to the bottom of the microsyringe barrel to avoid running off the solvent. Thus, microdroplet stability was significantly improved using the microsyringe barrel and the cooling process. This approach increased the contacting surface area of the organic extracting microdroplet and led to quantitative recoveries of both volatile and semi-volatile analytes within a short extraction time. The proposed cooling-assisted GP-MSE device was coupled to GC-MS and used to determine PAHs, OCPs and alkyl phenols (APs) in plant and solid samples. This system was further amended and employed to analyze xylene, PAHs, OCPs, polychlorinated biphenyls (PCBs), and APs as the target analytes, with different volatilities

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Carbon Nanotube Doped with Gaseous-phase Silica/Sulfur Composite as a Cathode Material for High-performance Lithium–Sulfur Batteries

Carbon Nanotube Doped with Gaseous-phase Silica/Sulfur Composite as a Cathode Material for High-performance Lithium–Sulfur Batteries

chemical oxidative method and obtained a specific capacity of approximately 696 mAh g −1 after 30 cycles at 0.1 C. Nevertheless, both methods are complex, and their electrochemical performance is not ideal. In our previous study [32], we discovered a facile method to synthesize a gaseous-phase silica (GPSiO 2 )/S cathode, which possesses high initial discharge capacity and long cycle life. Nonetheless,

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A Numerical Study of High Temperature and High Velocity Gaseous Hydrogen Flow in a Cooling Channel of a NTR Core

A Numerical Study of High Temperature and High Velocity Gaseous Hydrogen Flow in a Cooling Channel of a NTR Core

In the present study, a cooling channel of the NTR core is considered. The cooling channel is 1.2 meters long Stainless Steel pipe with an inner diameter of 2.54 meters (0.1inches). The thickness on the cooling channel is 0.125 mm. The left end of the pipe is the inlet through which the fluid (gaseous hydrogen) comes in at a constant temperature and mass flow rate and the right end of the pipe is the outlet, where the exit pressure is maintained at constant. Initially, hydrogen gas at the inlet is at 300 degree Kelvin. As the flow comes into the cooling channel with a mass flow rate of 0.005 kg/s, the temperature and the velocity of the fluid in the channel gradually increases due to the heat flux from the NTR core. Considering the Mach number and Reynolds’s number, the flow in the pipe can be categorized as turbulent and subsonic. The physical model of the cooling channel of the NTR core is shown in Figure 7.

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Ageing Property of Product Extracted From Hydropyrolytic Depolymerization of LDPE, LLDPE, MDPE and HDPE Type of Polyethylene

Ageing Property of Product Extracted From Hydropyrolytic Depolymerization of LDPE, LLDPE, MDPE and HDPE Type of Polyethylene

Hydroperoxide concentration was used as an indicator of the extent of polymer degradation in relation to exposure time in oven aging experiments performed at 100 ºC. Exposure time is the time period within which most structural changes of the studied product were detected. Structural factors, such as morphology, are helpful for the interpretation of such degradation profiles. This is shown in table 2. It was observed that most of the oxidation of the polyolefins is restricted to the amorphous phase because oxygen diffusion across the compact crystalline domains is very difficult. Highly amorphous polyethylene mix suffers from oxidation reactions to a greater extent. Colorimetric measurements of hydroperoxide, showed that after two weeks of polyethylene exposure, the hydroperoxide concentration curve displayed a plateau. Figure 3 describes the hydroperoxide concentrations within which the rate of formation and decomposition are in equilibrium.

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Review of Vehicle Emission Measurement and Sampling System

Review of Vehicle Emission Measurement and Sampling System

Particulate matter determined by Constant Volume Sampling is dependent on Dilution Ratio. In the inter laboratory comparison it is found that there is 20% of difference in Particulate Matter which are attributed in situations where outliers are excluded and the gaseous pollutants are agreed. To address this issue new regulation have been made in making efforts for improving the reproducibility between testing laboratories of different sites. If the Dilution is higher the there is a tough challenge to collect the sufficient amount of Particulate Matter for weighing. Since the mass of collected sample is comparable to the mass of gases which are absorbed by filters. To favour the determination of semi volatile Particulate matter higher Dilution ratio is preferred, but it is not clear that new particle formation is dependent on the Dilution Ratio which applies to filter based measurement. The formation of particles is totally dependent on the species concentration and cooling.

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Modeling of Silicon Vapor Phase Epitaxy Using Stefan Maxwell Formalism

Modeling of Silicon Vapor Phase Epitaxy Using Stefan Maxwell Formalism

The Iterative Method of Rao 8) is used to determine the equilibrium state for the Si-Cl-H system at a selected temperature in the 1200–1600 K range for specified input gas composition at 1.0 atm (= 101.325 kPa) total pressure. The Cl/H atom-ratio of the gas-phase remains the same, but the Si/Cl ratio falls as the system reaches equilibrium. The nine equilibrium constants (Table 1), total pressure and Cl/H ratio together provide eleven equations that enable one to determine partial pressures of species H 2 , HCl, Si, SiCl 4 ,

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The Procedure of Solving the Inverse Problem for Determining Surface Heat Transfer Coefficient between Liquefied Nitrogen and Inconel 718 Workpiece in Cryogenic Machining

The Procedure of Solving the Inverse Problem for Determining Surface Heat Transfer Coefficient between Liquefied Nitrogen and Inconel 718 Workpiece in Cryogenic Machining

The determination of the cooling effect is important since the phase (liquid and gaseous) has a significant influence on the cooling effect, which indirectly influences the integrity of the machined surface after machining process. Therefore, this paper presents how the phase of liquefied nitrogen influences the surface heat transfer coefficient. The determination of the phase has been defined by resolving the inverse problem with conducted experiments and verified by the design of a numerical simulation. The experimental part includes the temperature measurement in the material (a plate of Inconel 718) at the time when the nozzle has moved across the plate, and the design of the numerical simulation. The results have shown that the surface heat transfer coefficient reaches the maximum value of 75000 W/(m 2 K) at the

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Numerical Analysis on the Correlation between Wind Flow and Temperature Variation in High-Rise Apartment

Numerical Analysis on the Correlation between Wind Flow and Temperature Variation in High-Rise Apartment

Microalgaeas a feedstock, which can be used to produce renewable energy,have several advantages. They can be cultivated in sewage or barren fields. Their growth period is quite short. Besides these, they are carbon-neutral. That is, when their energy use as fuel, it doesn’t occur any increase in carbon dioxide emission in the atmosphere [3].But, bio-oil, that is the organic phase of algal pyrolytic liquid product, is not suitable to become fuel directly because of its low hydrocarbon content and other several disadvantages, like its high viscosity and low volatility. However these feedstock mainly composes of valuable compounds which have nitrogen or oxygen functionality [4].

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Planar Reflection of Gaseous Detonation

Planar Reflection of Gaseous Detonation

discrepancy is two-fold. First, we observe that the elastic peak-to-peak oscillation has a smaller amplitude in the experiment than the computation for some gauge locations. In previous simulations of the elastic response of tube walls due to detonation waves, such as those by Karnesky (2010), it was shown that the elastic oscillation can be accurately computed if factors such as circumferential wall thickness variation are included. It is possible that such a complicating factor is influencing the elastic strain predictions. Second, it was shown in section 2.4.1 that small differences in wave arrival time relative to the phase of elastic oscillation can produce substantial differences in the resulting plastic strain for the 200 kPa fill pressure case. This is depicted in figure 2.22, where computed and measured strain-time traces are plotted for the two locations marked in figure 2.20. In figure 2.22(a), we observe that the computed and experimental traces are in good agreement, both in arrival time of the reflected wave and in the resulting residual plastic strain. In figure 2.22(b), however, the modeled material response caused by the reflected shock wave occurs nearly half of a natural period before the measured response. This results in a completely different excitation of the cross-sectional vibration and a considerably larger computed final residual plastic strain. This illustrates the sensitive nature of the strain calculations to minor differences in reflected shock arrival time. Thus, we conclude that differences in the computed residual plastic strain originate from small differences in the elastic oscillation, particularly due to misalignment in the phase of the elastic oscillation when the reflected shock arrives.

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