Physical Properties Of Medium Research Articles

Dynamic seismic signatures in a fluid‐saturated porous periodically layered medium considering effects of intrinsic anisotropy

AbstractThe interlayer wave‐induced fluid flow is an important mechanism for seismic attenuation and dispersion, as well as frequency‐dependent anisotropy, in the fluid‐saturated porous layered medium. This mechanism is closely related to the medium physical properties, and thus quantifying this mechanism is of significance for the seismic inversion of medium physical properties. Although numerous models have been proposed to quantify this mechanism, most models do not consider the effects of layer intrinsic anisotropy. To solve this problem, the effective complex‐valued and frequency‐dependent stiffness coefficients are derived for the fluid‐saturated porous medium composed of periodic transversely isotropic layers. Using the derived solutions, we study the effects of layer intrinsic anisotropy on seismic dispersion and attenuation, as well as frequency‐dependent anisotropy. It has been found that different matrix or fluid property contrasts between adjacent layers lead to different effects of intrinsic anisotropy. In addition, the effects of intrinsic anisotropy are also influenced by the fluid distribution when both matrix and fluid properties contrast among adjacent layers exist. In the low‐ and high‐frequency limits of wave‐induced fluid flow, our model reduces to the previous known results, which validates the correctness of our model. Our model can be applied in the seismic inversion of physical properties of reservoirs with intrinsic anisotropy, such as shale and tight sandstone reservoirs. In addition, our model can also be extended to cases with more complex intrinsic anisotropy and, thus, can be applied to complex anisotropic fractured reservoirs in the future.

Comparative study of the effect of cross‐linking degree on chitosan hydrogels synthesized with low and medium molecular weight chitosan

AbstractChitosan (CS) is often used in hydrogels due to its natural origin, sustainability, non‐toxicity, and biodegradability. However, the physicochemical properties of CS hydrogels generated via physical cross‐linking are relatively poor. CS hydrogels were prepared by cross‐linking with glutaraldehyde (GA) at different ratios ranging from 1% to 10% (w/w), using two different molecular weight CS. The swelling degree of hydrogels was investigated at pH 2.0, 5.6, and 7.4. The structure, morphology, and thermal characteristics of hydrogels were examined using Fourier transform infrared, scanning electron microscopy, differential scanning calorimetry, and thermogravimetric analysis, respectively. Compression tests were conducted using Zwick/Roell universal testing equipment following ASTM D695. In vitro degradation studies were performed in enzyme and enzyme‐free mediums at pH 7.4. The study demonstrated that low molecular weight CS (L‐CS) hydrogels have a lower sol content and higher swelling values than medium molecular weight CS (M‐CS) hydrogels. Both L‐CS and M‐CS hydrogels cross‐linked with 1% GA showed maximum swelling degrees at pH 2.0. Thermal analysis concluded that M‐CS hydrogels have higher thermal stability than L‐CS hydrogels. It was also found that the M‐CS hydrogels have higher compressive moduli. The degradation experiments in both enzyme and enzyme‐free media showed that L‐CS hydrogels have higher degradation rates.Highlights Chemically cross‐linked hydrogels synthesized using low and medium molecular weight chitosan. The mechanical and physical properties of medium and low molecular weight chitosan hydrogels were compared. Degradation experiments were performed in both enzyme and enzyme‐free media. Swelling values decreased noticeably with the increasing molecular weight. Low molecular weight chitosan improved the biodegradability of hydrogels.

Assessment of thrust chamber stability margins to high-frequency oscillations based on mathematical modeling of coupled ‘injector – rocket combustion chamber’ dynamic system

High-frequency instability of a liquid-propellant rocket engine (LRE) during static firing tests is often accompanied by a significant increase in dynamic loads on the combustion chamber structure, often leading to a chamber destruction. This dynamic phenomenon can also be extremely dangerous for the dynamic strength of a liquid-propellant rocket engine. The calculation of acoustic combustion product oscillation parameters is important in the design and static firing tests of such rocket engines. The determination of the oscillation parameters (natural frequencies and stability margins such as oscillation decrement) is one of the problems solved in the LRE design period as part of the development of measures to ensure the engine stability. The main aim of the paper is to develop a numerical approach to determining the parameters of acoustic oscillations of combustion products in liquid-propellant rocket engines combustion chambers taking into account the features of combustion space configuration and the variability of gaseous medium physical properties depending on the axial length of the chamber, acoustic impedance in critical throat and dissipation effects (damping experimental values) in the shell structure and the gas media in the chamber. The approach is based on mathematical modeling of the coupled ‘chamber shell structure – gas’ dynamic system by using the finite element method and the CAE (Computer Aided Engineering) system. The developed approach testing and further analysis of the results for the RD 253 engine using nitrogen tetroxide and unsymmetrical dimethylhydrazine as a propellant pair were carried out. The dynamic system shapes and frequencies of longitudinal, tangential and radial modes are determined. The results of mathematical modeling of the dynamic system indicate a satisfactory agreement of the calculated decrements of the first longitudinal oscillation mode and third tangential oscillation mode with the experimental decrements obtained by hot-fire tests data. From system harmonic analysis of the thrust chamber, it follows that the dynamic pressure gain factor of the gas media in the chamber at the first longitudinal mode frequency is 1.6 times greater than the system dynamic gain in the tangential mode. At the same time, the oscillation decrement for the system tangential mode is 2 times smaller than that of the first longitudinal mode. This means that the thrust chamber tangential mode is more dangerous and can lead to rocket engine combustion instability. The effect of the injector on the high-frequency stability of the combustion chamber and the possibility of partial suppression of combustion chamber thermoacoustic oscillations by adjusting the high-frequency dynamics of the injector are shown theoretically.

Landslide Investigation Using Seismic Refraction Tomography Method: A Review

Since the early 1960s, near-surface seismic refraction tomography (SRT) has been extensively used as a non-invasive and cost-effective geophysical method to characterize complex geological structures for landslide investigation. This geophysical technique is able to characterize the slope material, the sliding surface's geometry, the landslide mass movement, the physical properties of media, and the water saturation effects on the slope. Therefore, this method has become an appropriate method due to the increasing progress of novel algorithms and the improvements of field-data collection systems. In this paper, we attempt to review the essential research that investigated various types of landslides influenced by water saturation and landslide materials and identified in various areas, since the year 2000. Significant conclusions obtained by applying different survey strategies and data processing algorithms in seismic refraction surveys are widely discussed concentrating on the advantages and disadvantages of this method. The main results obtained by the few available studies applying time-lapse SRT (TLSRT) are particularly analyzed.

ANALYTICAL SOLUTION OF THE FRACTAL CUBIC–QUINTIC DUFFING EQUATION

In this work, the fractal cubic–quintic Duffing’s equation analytical solution is obtained using the two-scale transform and elliptic functions. Then, the analytical solution is used to study wave propagation in a fractal medium. Since the value of the fractal parameter adjusts the pulse frequency and wavelength propagation velocity, depending upon the fractal medium physical properties, it is found that the information contained in the pulse can be carried out faster over long distances without distortion or loss of intensities. This paper offers a new light on the applicability of the two-scale transform of fractal theory to comprehend natural phenomena.

Pressure- and temperature-dependent physical metallurgy in a face-centered cubic NiCoFeCrMn high entropy alloy and its subsystems

The pressure and temperature dependence on the physical properties of medium and high entropy alloys is an intriguing topic in materials science and its different technological applications. In this study, the structural, elastic, mechanical, electronic, and thermal properties of Ni-based alloys are investigated by ab-initio molecular dynamics (AIMD) calculations and molecular dynamics (MD) simulations. First, the elastic, electronic, and mechanical properties of the Ni-based alloys are calculated; these include the bulk, shear, and Young’s moduli, the anisotropy factor, Poisson’s ratio, Pugh’s ratio, and the hardness. Next, the effects of temperature and pressure on the structural, elastic, mechanical, and electronic characteristics of Ni-based high entropy alloy and its subsystems are analyzed. In all cases, the 3d states have the dominant contributions to the electronic dispersion near the Fermi level. We have also investigated the lattice dynamical properties and found that the materials under consideration are dynamically stable. NiCoFeCrMn has the highest entropy among these alloys and subsystems. Moreover, it has a low thermal expansion coefficient, suggesting that it is suitable for high-temperature applications. Our simulation results unambiguously show the significance of considering the influence of temperature and pressure on the physical properties of Ni-based alloys for their high temperature and pressure applications.

Correlating Bromelain's activity with its structure and active-site dynamics and the medium's physical properties in a hydrated deep eutectic solvent.

Deep eutectic solvents (DESs) are emerging as new media of choice for biocatalysis due to their environmentally friendly nature, fine-tunability, and potential biocompatibility. This work deciphers the behaviour of bromelain in a ternary DES composed of acetamide, urea, and sorbitol at mole fractions of 0.5, 0.3, and 0.2, respectively (0.5Ac/0.3Ur/0.2Sor), with various degrees of hydration. Bromelain is an essential industrial proteolytic enzyme, and the chosen DES is non-ionic and liquid at room temperature. This provides us with a unique opportunity to contemplate protein behaviour in a non-ionic DES for the very first time. Our results infer that at a low DES concentration (up to 30% V/V DES), bromelain adopts a more compact structural conformation, whereas at higher DES concentrations, it becomes somewhat elongated. The microsecond conformational fluctuation time around the active site of bromelain gradually increases with increasing DES concentration, especially beyond 30% V/V. Interestingly, bromelain retains most of its enzymatic activity in the DES, and at some concentrations, the activity is even higher compared with its native state. Furthermore, we correlate the activity of bromelain with its structure, its active-site dynamics, and the physical properties of the medium. Our results demonstrate that the compact structural conformation and flexibility of the active site of bromelain favour its proteolytic activity. Similarly, a medium with increased polarity and decreased viscosity is favourable for its activity. The presented physical insights into how enzymatic activity depends on the protein structure and dynamics and the physical properties of the medium might provide useful guidelines for the rational design of DESs as biocatalytic media.

Flowering times and some growth indicators of strawberry were affected by physical properties of the growing media

The evaluation of the physical properties of growing media seems essential in crops such as strawberry, which their flowering depends on environmental parameters. Thus, this study aimed to evaluate Fragaria × ananassa development in growing media with different physical properties. For this purpose, it was focused on the correlation of growing media properties with the flowering time and some growth indices in different strawberry cultivars (i.e., ‘Camarosa’, ‘Mrak’, and ‘Selva’). The physical properties of growing media determined included pH, Electrical conductivity (EC), porosity, bulk density, particle density, organic and inorganic materials, water-holding capacity, and air-filled porosity. The flowering and growth responses of studied cultivars to growing media were different. Such that the rice hull growing medium accelerated the flowering time in ‘Camarosa’ and ‘Mrak’. ‘Camarosa’ and ‘Selva’ showed slow growth in rice hull, and ‘Mrak’ grew slowly in media of rice hull and sycamore pruning waste. An increase in the porosity or decrease in the bulk density accelerated the floral emergence and blooming in ‘Camarosa’. An increase in the air-filled porosity accelerated the floral emergence and blooming, and the beginning time of the fruit set in ‘Mrak’.It was also observed a reduction of the leaf number with increasing the porosity in ‘Mrak’. Decreasing each of the EC and bulk density also increasing the porosity reduced leaves number to the flowering step for ‘Camarosa’.Based on these observations, it was considered that the effect of growing media on flowering time and growth indices was genotype-dependent in strawberry such that flowering and growth responses of ‘Selva’ showed less correlation with the physical properties of media.

Key issues and innovative double-tangential circular boiler configurations for the 1000 MW coal-fired supercritical carbon dioxide power plant

When supercritical carbon dioxide (S–CO2) Brayton cycle is introduced into conventional coal-fired power plant, there exists the problems in S–CO2 boiler configurations due to the working medium physical properties’ change. This paper is taking a typical 1000 MW single reheat double-tangential circular boiler as example and investigations focus on the key issues of S–CO2 power plant with traditional boiler configuration from the thermodynamic system, combustion and heat transfer in the furnace, flow and heat transfer in tube. The results show that the studied traditional boiler configuration does not adapt for the 1000 MW S–CO2 coal-fired single reheat power plant for the mismatch heat duty. The effects of boiler size and flue gas recirculation ratio on the heat duty distribution and boiler performance are analyzed. Decreasing the boiler heat duty singly will have a negative impact on boiler performance. The newly developed “partial expansion at the upper zone + double furnace + symmetry flow mode” boiler configurations for the S–CO2 Brayton cycle are presented in order to coordinate the heat duty distribution and boiler performance. The overall net efficiency of the innovative 1000 MW single reheat S–CO2 power plant is up to 48.26%, higher ∼4% than the same-grade traditional steam power plant.

Tunable Thermo‐ and pH‐Responsive Hydrogels and MWCNTs/Hydrogel Containing 2‐Aminobenzamide Units in Their Crosslink Chains

AbstractIn the present article, a new class of chitosan hydrogels containing 2‐aminobenzamide units in their crosslink chains was prepared by reaction of chitosan with different percentages of bis‐isatoic anhydride as cross‐linker at 70 °C. Then, multi‐walled carbon nanotubes (MWCNTs)/hydrogel nanocomposites were fabricated by crosslinking of chitosan with bis‐isatoic anhydride in the presence of 0.1% and 0.3% (w/w) MWCNTs. Scanning electron microscopy images have verified a 3D porous nanostructure with uniform morphology which MWCNTs were dispersed uniformly on the matrix of hydrogel nanocomposite. The swelling behaviours of the hydrogels and their nanocomposites were investigated by swelling the gels in media of different temperatures and pH. The results indicated the pH‐thermo dual behaviour of hydrogels. Finally, metronidazole was selected as a model drug for the investigation of the drug release properties of the prepared hydrogels. The metronidazole release was affected by physical properties of medium and chemical content of hydrogels.

GAME: GAlaxy Machine learning for Emission lines

We present an updated, optimized version of GAME (GAlaxy Machine learning for Emission lines), a code designed to infer key interstellar medium physical properties from emission line intensities of UV/optical/far infrared galaxy spectra. The improvements concern: (a) an enlarged spectral library including Pop III stars; (b) the inclusion of spectral noise in the training procedure, and (c) an accurate evaluation of uncertainties. We extensively validate the optimized code and compare its performance against empirical methods and other available emission line codes (PYQZ and HII-CHI-MISTRY) on a sample of 62 SDSS stacked galaxy spectra and 75 observed HII regions. Very good agreement is found for metallicity. However, ionization parameters derived by GAME tend to be higher. We show that this is due to the use of too limited libraries in the other codes. The main advantages of GAME are the simultaneous use of all the measured spectral lines, and the extremely short computational times. We finally discuss the code potential and limitations.

Hydrologic experiments and modeling of two laboratory bioretention systems under different boundary conditions

Hydrologic performance of bioretention systems is significantly influenced by the media composition and underdrain configuration. This research measured hydrologic performance of column-scale bioretention systems during a synthetic design storm of 25.9 mm, assuming a system area:catchment area ratio of 5%. The laboratory experiments involved two different engineered media and two different drainage configurations. Results show that the two engineered media with different sand aggregates were able to retain about 36% of the inflow volume with free drainage configuration. However, the medium with marine sand is better at delaying the occurrence of drainage than the one with pumice sand, denoting the better detention ability of the former. For both engineered media, an underdrain configuration with internal water storage (IWS) zone lowered drainage volume and peak drainage rate as well as delayed the occurrence of drainage and peak drainage rate, as compared to a free drainage configuration. The USEPA SWMM v5.1.11 model was applied for the free drainage configuration case, and there is a reasonable fit between observed and modeled drainage-rates when media-specific characteristics are available. For the IWS drainage configuration case, air entrapment was observed to occur in the engineered medium with marine sand. Filling of an IWS zone is most likely to be influenced by many factors, such as the structure of the bioretention system, medium physical and hydraulic properties, and inflow characteristics. More research is needed on the analysis and modeling of hydrologic process in bioretention with IWS drainage configuration.

Correlations of medium physical properties and process performance in solid-state fermentation

The medium of solid-state fermentation (SSF) is a multiphase system, whose complex physical properties cause difficulties of the cognition of SSF process and the process control. This paper aimed to deeply analyze the mechanical, structural and thermal properties of solid-state medium, explored relationships between the medium’s physical properties and fermentation performance, then to guide the process control and culture medium optimization for SSF. A mechanical property index (Imp), which was the product of resilience, cohesiveness, and springiness, was established to fully characterize physical properties of medium. Results showed at the initial stage of SSF, there were positive correlations of Imp with thermal conductivity and water retention, negative correlations with gas permeability and thermal diffusivity, and a parabolic relationship with biomass content with a symmetry-axis at Imp=4.37×10−2. Correlations were further verified in SSF dynamic process. During the first 100h, Imp≤4.37×10−2 was positively correlated with heat conduction and water retention in medium, which was beneficial for cell growth; while when Imp>4.37×10−2 during 100–168h, medium heat accumulation, poor heat diffusivity and poor gas permeability indicated the reduction of fermentation performance. Results revealed medium physical properties significantly affected heat and mass transfer and further influenced fermentation performance in SSF. Mechanical property index Imp could well comprehensively characterize physical properties of medium, which could be useful for guiding initial culture medium preparation and SSF process control.

Characterization of Biofilm Bacterial Communities in a Vertical Unsaturated-Flow Bioreactor Treating Domestic Greywater

Greywater (GW) is wastewater generated from domestic activities without the input of toilet and kitchen. Its reuse can help to reduce the overall potable water consumption in urban areas. In the current study, an extensive greywater treatment unit consisting of an attached growth unsaturated-flow bio-reactor, with “BIOROCK”® medium, was developed. Its performance was studied and the bacterial communities of the BIOROCK® biofilm were characterized through 454-pyrosequencing of 16S rRNA genes. The medium physical properties (porosity and high specific surface) made it possible to support highly diverse and relatively long-term stable bacterial communities that showed spatial variations in their relative abundance. The bacterial communities were dominated by genera previously associated with wastewater environments and that present some kind of degrading activities. Consequently, after treatment, water turbidity was reduced by 83 % and COD removal efficiency was 80 %, demonstrating that most of the biodegradable matter had been removed. Some pathogens were detected, but usually at low abundances. With some minor adjustments and the addition of a chlorination step, the treated greywater generated by this system can be used for non-potable purposes, such as irrigation and toilet flushing.

Critical conditions for thermal explosion in a plate with a nonlinear heat source

The exact analytical solution of the nonstationary heat conduction problem with a nonlinear internal heat source at the nonsymmetric third-type boundary conditions was obtained by the method of variable separation. The relations between the boundary condition parameters and a heat source separating the stationary processes from processes of an unlimited temperature increase (thermal explosion) were found. For known physical properties of medium, the maximum allowable value of the specific power of a heat source has been found. If nonsymmetric boundary conditions are exceeded on wall surfaces, it can lead to thermal destruction.

Study on the velocity structure of the crust in Southwest Yunnan of the north-south seismic belt—Results from the Menghai-Gengma-Lushui deep seismic sounding profile

Southwest Yunnan, located in the southern segment of the north-south seismic belt, is one of the regions with strong tectonic movement and seismic activity in China. Study on the characteristics of tectonic setting and deep geophysical field in the region is an important issue in basic science. In 2013, we conducted a 600-km-long Menghai-Gengma-Lushui profile of deep seismic wide-angle reflection/refraction and high-resolution seismic refraction in Southwest Yunnan. In this paper, we use 6 groups of clear intracrustal P-wave phases picked from the seismic record sections of 11 shots to build a velocity structure model of basement and 2D crustal P-wave of the region by using finite difference inversion and ray travel time forward fitting technology. The results show that, from south to north, the crust gradually thickens along the profile and its basement shows a significant lateral heterogeneity. In the vicinity of the Nanting River fault, the basement structure shows the character of alternate depressions and uplifts, and the shallowest basement is about 1.0 km. In the vicinity of Tengchong and Lancang, the basement is about 5.0 km deep. The velocity of the middle and lower crust in the region generally increases with the increasing of depth. At the block boundary and beneath the fault tectonic belt, the velocity contours show apparent irregularity and the P-wave velocity changes sharply. In this region, the Moho gradually deepens from south to north with relatively large lateral undulations. The shallowest point of the Moho is located near Menghai at a depth of about 32.0 km. The deepest point of the Moho is located near Tengchong at a depth of about 40.5 km. Between Gengma and Yongde, the Moho shows significantly fast uplifting and depressing with an amplitude of about 4.0 km. Beneath the Nanting River fault, Longling-Ruili fault, Dayingjiang fault and Tengchong volcano, the basement velocity structure, 2D crustal P-wave velocity structure, distribution of average profile velocity and intracrustal interface spreading also show significant changes from the basement to the top of the Moho, indicating that the crustal velocity and medium physical properties beneath the fault tectonic belt are apparently different from the crustal materials on its both sides, which suggests that these faults should be in a certain scale and may extend to the lower crust or the top of the upper mantle. The earthquakes in the region mainly occurred at a depth of 10–20 km, and the seismic activity is related to the intracrustal medium velocity difference and fault belt distribution. The results can serve as the important data of the crust-mantle structure for the analysis of the deep tectonic setting, earthquake precise positioning, seismogenic structure modeling of the seismic activities in Southwest Yunnan, as well as the important reference for the evaluation of seismic hazard and the planning of earthquake disaster mitigation of this region.

Effect of plant growth on some physical properties of potting culture media

Physical properties of substrates considered appropriate for plant growth at planting may change over time in containers as a result of several processes. Changes include air space reduction, shrinkage of the substrate, organic matter decomposition, and physical breakdown of particles. The objective of this research was to evaluate the physical properties of date palm waste as culture media and its effect on number and yield of tomato fruit. The experiment was conducted as factorial in a completely randomized block design with 9 treatments and 3 replications. Treatments included three sizes (S 1 = <0.5, S 2 = 0.5–1, and S 3 = 1–2 cm) and three composting times (C 1 = 0, C 2 = 3, and C 3 = 6 months) of date palm waste. Statistical analysis showed that the values of bulk density (BD) and water holding capacity (WHC) were significantly increased at the end of cultivation from culture media without plant in comparison to before and after planting (p < 0.05). Amounts of F t (total porosity) in culture media without plant were significantly higher than those in culture media before planting and with plant (p < 0.05). Also during the experiment, an apparent shift in physical properties was recorded. The overall results of this research indicated that composting process changed the physical properties of the media before planting. Also during the experiment, an apparent shift in physical properties was recorded. The results of the study showed that composting processes continued in culture media with and without plant, in the mean time, the composting processes were higher in culture media without plant.

Relating Non-equilibrium Solute Transport and Porous Media Physical Characteristics

Breakthrough data for solute tracer transport at different velocities, covering a wide range of particle sizes and particle shapes corresponding to 324 breakthrough curves, were used in this study. Analysis was carried out for three granular porous media: crushed granite, gravel, and Leca® (a commercial insulation material). Mobile–immobile phase (MIM) solute transport parameters (dispersivity, mass transfer, and mobile (active) porosity) for non-equilibrium mass transport were determined for each breakthrough curve by fitting a MIM solute transport model to the breakthrough data. The resulting set of solute transport parameters was correlated with porous medium physical properties (particle size distribution and particle shape) to establish a set of simple expressions for estimating the MIM solute transport parameters. Linear expressions for predicting the solute dispersivity, mass transfer, and mobile phase porosity from porous medium particle size distribution (mean particle diameter and width of particle size distribution) and particle shape were developed based on regression analysis. A partial validation of these expressions indicated that the developed expressions are able to accurately predict solute transport parameters from porous medium physical properties.

The Study of the Difference Methods with Variable Grids Seismic Wave Numerical Simulation in Multi-Scale Complex Media

In the process of seismic wave field numerical simulation using finite difference method, the simulation accuracy and computational efficiency is one of the keys to the problem which is especially important to the numerical simulation of small scale geological body which velocity changes violently. In order to describe the local structure of medium subtly and guarantee the efficiency of the simulation, this article introduces the variable grid finite difference method to the staggered grid high-order finite difference numerical simulation on the basic of the traditional staggered grid finite difference algorithm to improve the staggered grid spatial algorithm and avoid the reduction of the simulation accuracy and computational efficiency caused by the interpolation factor. The results show that the variable staggered grid numerical simulation of finite difference algorithm can accurately depict the space variation of underground medium physical properties to further enhance the adaptability of numerical simulation of complex medium, it also can provide reliable basis for wave field imaging and the combined interpretation of p-wave and s-wave.

채소재배용 발포 폴리프로필렌 소재화분에 적합한 인공배지의 선발

This experiment was conducted to select light and good water-holding medium suitable for expanded polypropylene(EPP) pot judging from the growth reaction of vegetables on artificial medium. Solidity ratios were 27.4% in medium A of control and about 10% in medium B~E respectively. Vapor ratio was 90% in medium B~E, which was statistically higher than that of 72.6% in medium A. Water-holding capacities were 63.6g in medium A and more than 70g in medium B~E. pH in medium B was highest by 5.6 and pHs of medium C, D, E were higher in order. EC of medium A was the highest by 2.16 ds/m but those of medium B~E were very low by 0.43 ds/m under. Physical properties of medium used were not changed. Leaf number of endive were most by 19.2 in medium D, E. Leaf length and width of lettuce were about 19cm and 11cm in medium B~E showing no difference in medium, which were larger than 14.7cm and 9.1cm in medium A respectively. Number of leaves and root length in medium B~E were larger than medium A like leaf sizes. Leaf length of mustard in medium B~E were significantly longer than medium A. Stem lengths of tomato in medium C~E were about 50cm, which is longer than medium A. Flowering dates were the earliest on 28th of July in medium D, second earliest on 30th of July in medium E. Number of fruits showed no significant difference among medium but was the most in medium E by 8. From the above results, artificial medium made in this experiment was lightweight and had good water-holding capacity compared to existing horticultural medium on sale. It was judged that the most suitable medium for endive, lettuce, mustard, tomato is E (Coco peat:Peat moss:Sphagnum moss=2:5:3) considering growth of vegetables and the physicochemical properties of medium. Keywords: Growth , Lettuce , Lightweight , Tomato , Water holding capacity