Plastic Cylinder Research Articles

Effect of the Application Procedure on The Bond Strength of Universal Adhesive in Restoration Repair

Objective: This study aimed to evaluate the effect of reduced application time on the bond strength of a universal adhesive used for the repair of hybrid ceramic and composite resin restorations. Methods: In the study, a total of 48 rectangular prisms of sizes 7×6×2 mm hybrid ceramic (Vita Enamic, Zahnfabrik, Germany) and composite resin (Solare X, GC, Japan) specimens were prepared. All samples were aged with 5000 thermal cycles. Then, the upper surfaces of the samples were roughened with a diamond fissure bur (10–36µ, 852 FG Meisinger; Hager & Meisinger GmbH, Germany) with 5 strokes under water cooling. The samples were divided into 2 subgroups according to the different application times of the adhesive system (G-Premio Bond, GC, Japan) (n=12). Then, composite resin (Solare X, GC) was placed using plastic cylinder molds with 3 mm inner diameter and height and cured with light for 20 seconds. All samples were thermal aged and then a shear bond strength test was conducted. The data were analyzed with Two-way ANOVA and post-hoc Tukey HSD tests (p˂0,05). Results: Two-way ANOVA revealed that the repair bond strength of the 10 seconds of waiting was significantly higher than the quick application for both hybrid ceramic and composite resin (p˂0,05). It was determined that there was no significant difference between hybrid ceramic and composite resin in the both quick application group and 10 seconds waiting group (p˃0,05). Conclusion: Quick application procedure showed lower shear bond strength than 10 seconds waiting group for the repair of both composite resin and hybrid ceramic (p<0,05). Keywords: Quick application, Application time, Universal adhesive, restoration repair..

Aerodynamics Behavior in High Speed Sports Jersey Fabrics with Different Roughness

Enhancing aerodynamic performance holds paramount importance in high-speed sports, leading to a growing interest in garments that can positively impact aerodynamic efficiency. Wind tunnel experimentation has played a pivotal role in assessing aerodynamic properties, employing both cylinder and leg models within a closed return circuit tunnel setup. Utilizing a plastic cylinder model, researchers evaluated the aerodynamic properties of various knitted samples, with dummy cylinders introduced to minimize 3D flow effects and ensure adherence to the infinite length hypothesis. By employing the foot and knee as additional dummy components, efforts were made to further mitigate 3D flow effects. These wind tunnel tests encompassed nine knitted single jersey fabrics, predominantly composed of 100% polyester, subjected to speeds ranging from 20 to 80 km/h to simulate real-world sporting conditions. The findings revealed a significant correlation between fabric manufacturing, indicated by the cover factor, and fabric roughness, with discernible impacts on aerodynamic parameters. Notably, consistent aerodynamic behaviors were observed across fabric tests conducted on both the cylinder and leg models, underscoring the reliability of the experimental setup.

Adaptability of VisCalor versus bulk-fill composites using scanning electron microscope: an in-vitro study

Purpose To evaluate the marginal integrity of two types of bulk-fill composite resins in Class I box-shaped cavities. Materials and methods Forty extracted human sound molars were selected. The teeth were fixed with sticky wax to the base of plastic cylinder and the cylinder was filled with self-curing acrylic resin so that only root was embedded. Simple Class I box-shaped cavities were prepared using a fissure carbide bur with water spray and finished with fine-grained flame burs. The overall dimensions and depth of the cavities were standardized as follows: 4 mm length mesiodistally and 3 mm width buccolingually and up to 4 mm depth. All prepared cavities were bonded using Futurabond M+ one-step self-etch adhesive system. The teeth were randomly divided into two groups (n = 20 teeth each): group I: specimens were restored with VisCalor composite bulk-fill composite resin, which is heated before insertion using a VisCalor dispenser dental device. Group II: specimens were directly restored with X-tra fill bulk-fill composite resin without preheating. After curing, finishing and polishing were performed. Each group was subdivided into two subgroups a and b (n = 10) according to whether subjecting 500 thermocycling fluctuations or not. Each specimen was sectioned buccolingually through the center of the composite resin restoration in two halves, and then cleaned under running tap water and subjected to thorough ultrasonic cleaning to get rid of both soft and hard surface deposits. All sectional samples were fixated in cylindrical carriers, and a thin layer of gold was applied to the surfaces. The marginal adaptation of composite restorations and ultramorphology of adhesive bonds were analyzed at ×50, ×1000 magnification, with a scanning electron microscope. ×50 magnification was utilized to measure the length of margins free gap in enamel and dentin by Autodesk Auto CAD program and expressed in mm/percent. All data of measurements of the length of nongaped margins in enamel and dentin are collected, tabulated, and statistically analyzed. Results Group Ia (VisCalor bulk-fill not thermocycled), recorded the highest mean value of marginal free-gap with 10.26 ± 0.27 mm (93.31%), while group IIb (X-tra-fill bulk-fill thermocycled) recorded the lowest mean value in 7.90 ± 0.26 mm (73.04%) and the difference was statistically highly significant (P = 0.000). In general, group I recorded higher mean values of marginal free gap and adaptation in mm/percent than group II, and the difference was statistically highly significant at P value of 0.000 (9.86 ± 0.55 and 8.23 ± 0.39 mm and 89.15 ± 5.38 and 74.89 ± 3.69%, respectively). Bulk-fill restorations without thermocycling exhibited a higher mean value of marginal free gap and adaptation in mm/percent than the thermocycled one with a significant difference recorded at P value of 0.005. Conclusion Using preheated VisCalor bulk-fill composites could decrease the marginal gap formation improving the continuity at the tooth–restorative material interface than conventional bulk-fill restorations. On the other hand, thermocycling.

Drop damage analysis of automotive high-pressure composite hydrogen storage cylinders

With the world facing an energy crisis today, hydrogen is attracting attention as a renewable and clean energy source.In this paper, a carbon fiber fully wound plastic liner hydrogen storage cylinder (type IV cylinder) was modeled by software. Then the model was subjected to drop simulation, and by changing the drop height, the drop angle and the residual pressure inside the cylinder, the curve and the cloud diagram of the maximum total stress over time as well as the cloud diagram of the positive stress in all directions and the shear stress in all planes of the cylinder were obtained during the drop process. Meanwhile, by comparing the data and images under each working condition, it can be known that the location where the maximum stress appears is always near the spherical end and the pole hole, but the maximum stress is not a single-valued function of the drop height, and it is also related to the drop angle; and the maximum stress as a whole increases with the increase of the residual pressure. At the end of the article, a drop simulation of the conceptual unlined composite high-pressure hydrogen storage cylinder (V-cylinder) is also carried out, and it is found that the maximum stress during the drop is basically equal to that of the lined high-pressure hydrogen storage cylinder, and the liner mainly plays the role of preventing leakage and corrosion, and does not bear the stress loads.

Multi-point calorimeter using distributed fiber Bragg gratings for small field dosimetry in radiotherapy.

The interest of using fiber Bragg gratings (FBGs) dosimeters in radiotherapy (RT) lies in their (i) microliter detection volume, (ii) customizable spatial resolution, (iii) multi-point dose measurement, (iv) real-time data acquisition and (v) insensitivity to Cherenkov light. These characteristics could prove very useful for characterizing dose distributions of small and nonstandard fields with high spatialresolution. We developed a multi-point FBGs dosimeter customized for small field RT dosimetry with a spatial resolution of 1mm. The 3cm-long multi-point dosimeter is made by embedding a 80 silica fiber containing an array of thirty (30) co-located 1mm-long fs-written FBGs inside a plastic cylinder with an UV curing optical adhesive. With its higher thermal expansion coefficient, the plastic cylinder increases the sensitivity of the dosimeter by stretching the fiber containing the FBGs when the temperature rises slightly due to radiation energy deposition. Irradiations (2000MU at 600MU/min) were performed with a Varian TrueBeam linearaccelerator. The dose profile of a 2 2cm 6MV beam was measured with a mean relative difference of 1.8% (excluding the penumbra region). The measured output factors for a 6MV beam are in general agreement with the expected values within the experimental uncertainty (except for the 2 2cm field). The detector response to different energy of photon and electron beams is within 5% of the mean response ( pm/Gy). The calorimeter's post-irradiation thermal decay is in agreement with thetheory. An energy-independent small field calorimeter that allows dose profile and output factor measurements for RT using FBGs was developed, which, to our knowledge, has never been done before. This type of detector could prove really useful for small field dosimetry, but also potentially for MRI-LINAC since FBGs are insensitive to magnetic fields and for FLASH since FBGs have been used to measure doses up to100kGy.

Resorbable bilayer membrane made of L-lactide-ε-caprolactone in guided bone regeneration: an in vivo experimental study

PurposeGuided bone regeneration (GBR) is an accepted method in dental practice that can successfully increase the bone volume of the host at sites chosen for implant placement; however, existing GBR membranes exhibit rapid absorption and lack of adequate space maintenance capabilities. We aimed to compare the effectiveness of a newly developed resorbable bilayer membrane composed of poly (l-lactic acid) and poly (-caprolactone) (PLACL) with that of a collagen membrane in a rat GBR model.MethodsThe rat calvaria was used as an experimental model, in which a plastic cylinder was placed. We operated on 40 male Fisher rats and subsequently performed micro-computed tomography and histomorphometric analyses to assess bone regeneration.ResultsSignificant bone regeneration was observed, which was and similar across all the experimental groups. However, after 24 weeks, the PLACL membrane demonstrated significant resilience, and sporadic partial degradation. This extended preservation of the barrier effect has great potential to facilitate optimal bone regeneration.ConclusionsThe PLACL membrane is a promising alternative to GBR. By providing a durable barrier and supporting bone regeneration over an extended period, this resorbable bilayer membrane could address the limitations of the current membranes. Nevertheless, further studies and clinical trials are warranted to validate the efficacy and safety of The PLACL membrane in humans.

Perlite Has Similar Diffusion Properties for Oxygen and Carbon Dioxide to Snow: Implications for Avalanche Safety Equipment Testing and Breathing Studies

On average, one hundred people die each year under avalanche snow. Despite extensive global research on gas exchange in buried avalanche victims, it remains unclear how the diffusion of respiratory gases affects survival under avalanche snow. This study aims to determine how oxygen and carbon dioxide diffuse through snow, as well as through wet and dry perlite, which may serve as a surrogate for avalanche snow. A custom-made apparatus to study the diffusion of respiratory gases consisted of a plastic cylinder (1200 mm long, ID 300 mm) with 13 gas sampling needles evenly spaced along the axis of the cylinder filled with the tested material. Following 60 min of free diffusion, gas samples were analyzed using a vital signs monitor with a module for respiratory gas analysis (E-CAiOVX, Datex-Ohmeda, GE Healthcare, Chicago, IL, USA). A combination of 16% oxygen, 5% carbon dioxide, and 79% nitrogen was used. The rates of diffusion for both respiratory gases were comparable in snow and both forms of perlite. Oxygen propagated faster than carbon dioxide. Due to similar diffusion characteristics to snow, perlite possesses the potential to stand in as an effective substitute for soft snow for the study of respiratory dynamics, for conducting breathing experiments, and for testing avalanche safety equipment.

Effect of Date Residues and Organic Acids on Some Physical Properties of Gypsiferous Soil

A laboratory experiment was carried out at the College of Agriculture, University of Anbar, located at 43°20‘09.7“E longitude, 33°25‘36.7“N latitude for the period from 1/10/2021 to 1/10/2022, to study the effect of date residues, organic acids, and wetting / drying cycles on some physical properties of gypsiferous soil. The soil was selected from the site of the Fallujah palm station that located at longitude 43º51'. 05. 36 E. and latitude 33º17'. 46. 82‘N., date residues were added in three levels, without addition (comparison treatment), 0.1% and 0.2% mixed with soil. Organic acids was added at 0% and 0.1% and packaged in plastic cylinders and the treatments were exposed for two levels of wetting and drying cycles (6 and 8) cycles. The stability of aggregates, dispersion ratio, saturated hydraulic conductivity, and cumulative infiltration were measured. The results showed that the addition of date residues by 0.2% improved all the physical properties. Aggregates stability values increased by 13.41% and saturated hydraulic conductivity values decreased, which reached 4.33 cm.h-1. Accumulator infiltration up to 24.01cm and the capillary height reached to 40.0 cm, while the dispersion rate decreased to 37. 27%. The aggregates stability increased and the dispersion ratio, water conductivity and infiltration decreased by adding organic acids when their averages reached 12.12%, 40.77%, 5.19 cm-1 and 21.41cm, respectively. Increasing the number of wetting / drying cycles negatively affected most of the studied properties, as the dispersion ratio increased to 42.08%, and the cumulative infiltration decreased to 21.73 cm.

Research on Deformation of Hydraulic Cylinders Made of Plastics

The article presents an author’s approach to the study of the behavior of plastic hydraulic cylinder structures under load. Plastics as design materials, due to their different properties, behave differently from metals. So far, there is little information about hydraulic cylinders made of plastics. They are a technical novelty, and there are no established standards or research methods for them. The tests were carried out on the example of two models of different internal diameter, the smaller one being Ø30 mm and the larger one Ø50 mm. Information was gathered by FEM simulation tests and tests of real models on a special test stand. The simulation section presents geometric models, discrete models and assumed boundary conditions, as well as the results of the performed simulations. For tests of real models, a description of the stand with the measuring equipment used is presented, e.g., laser displacement sensors, as well as the method of conducting the tests and the results. Then, the results are analyzed and compared. Deformations of the examined structures are discussed, e.g., tube swelling or deflection, which seem to be characteristic for plastic cylinders. Finally, the possibility of using selected plastics for the design material of hydraulic cylinders and the suitability of the research method used are assessed.

X-ray 3D Imaging of Low-Density Laser-Target Materials

Achieving optimal design and precise control of the internal structure of laser-target materials are the primary objectives in various laser physics experiments, particularly in generating high flux photon and neutron beams. The study of low-density materials poses considerable challenges for X-ray analysis due to their high transparency and minimal contrast. In this study, to obtain clear visualization of foams with sparse structures, we used phase-contrast X-ray tomography, utilizing a high-quality monochromatic X-ray beam from the synchrotron radiation source PETRA-III at DESY. Employing phase-contrast algorithms, the 3D structure of a foam-suspended glass microsphere inside the plastic cylinder was reconstructed with a level of image quality sufficient to visualize uniformity, displacement, and surface roughness on both sides of the microsphere. The primary focus of this investigation was a CH plastic capillary including 10 mg/cc CHO foam with a glass microsphere positioned at the center. The results of this study demonstrate that phase-contrast X-ray tomography with coherent synchrotron radiation is an effective and valuable technique for the development of new laser targets containing structured low-density materials.

A MONTE CARLO CALIBRATION APPROACH FOR A DUAL-ENERGY CT SYSTEM

This work shows the effectiveness of Monte Carlo methods for calibrating a dual-energy CT (DECT) system on a heterogeneous phantom for radiotherapy. The reference phantom comprising 20 inserts of different materials and densities representing human tissues inserted in a plastic water cylinder has been considered. The reliability of the model, built with the Penelope code, has been verified by comparing the results of the simulations at 80[Formula: see text]kVp and 140[Formula: see text]kVp with the experimental data acquired from the CT scans and dosimetry measurements. The effective atomic number from the various materials is also considered a control parameter. Tests for calibration and dose calculation are also based on a homogeneous phantom in PMMA and measurements in air with an ionization chamber. The Monte Carlo simulations coupled with dose evaluations allowed the calibration of the dose deposition effects on the considered tissue models.

Investigation of spherical and non-spherical binary particles flow characteristics in a discharge hopper

The particulate flow characteristics of granular particles including mung beans, wooden spheres, wooden cylinders, wooden cubic, plastic spheres, plastic cylinders, and their binary mixtures in a flat bottom hopper were studied experimentally using high-speed high-resolution camera recordings. An image processing method based on the color threshold was developed to calculate the area ratio for binary mixtures. The mass discharge rates, the residue inclination angles, and the changes in edge height and center height with time were also investigated. In addition, the effects of different initial packing patterns on the particulate flow, mixing and segregation behaviors were analyzed and compared. It is interesting to find that the shape of particles and the initial binary particle packing patterns have significant effects on the discharging characteristics. The results of this study provide helpful guidance for industrial applications and provide experiment data for computational model validation.

Elucidation of the relationship between masticatory muscle activity and masticatory movement. Report 1. Mechanism of occlusal force generation.

The purpose of this study was to elucidate how masticatory muscles are involved in the generation of occlusal force. The experiment was conducted by fabricating an experimental apparatus for a unilateral occlusion model with the masticatory muscles imparted. The experimental apparatus was fabricated by enlarging the lateral photograph of a dried adult skull specimen 3.5 times larger than that of a standard adult and drawing the outlines of the maxilla and mandible, canines and molars of the upper and lower jaws, and temporomandibular joint on a wooden board. The masticatory muscles used in the experiment were the masseter muscle, the temporalis muscle (anterior and posterior muscle bundles), and the lateral pterygoid muscle. For the measurement of the contractile force of the masticatory muscle, we used the spring scale. For the food, we used cut plastic cylinders. The results of the experiment revealed the following: First, the occlusal force was generated under the condition that the contraction forces of all the masticatory muscles were balanced. Second, when the occlusal force was applied to food, the occlusal planes of the upper and lower jaws were parallel. Third, the occlusal force occurred perpendicular to the occlusal plane. Fourth, the occlusal force was generated with a force greater than the contraction force of the individual masticatory muscles. And finally, even if occlusal force was applied to the food, the occlusal force did not load the temporomandibular joint. Occlusal force is not generated by the action of a single masticatory muscle but under the balanced contractile force of all masticatory muscles. The occlusal force then emerges with a force greater than the contraction force of all the masticatory muscles, and its direction occurs perpendicular to the occlusal plane.

Seismic upgrading of existing RC frames with displacement-restraint cable bracing

Cable braces are widely used for seismically upgrading existing frames due to the significant strength, stiffness, and superior economy. This study investigates the behavior of a cost-effective and easy-to-install displacement-restraint cable bracing technique (cable-cylinder) for seismic upgrading of RC frames. To this aim, a set of 4, 8, and 12-story RC Intermediate Moment Frames (IMFs) with low-stiffness plastic cylinders were considered. The following archetypes were studied: (OF): the Original Frame only, (CB): refers to adding conventional Cable Braces, and (CCB): represents the models with the Cable Cylinder Braces. Opensees software with lump-plasticity approach was employed to model the moment-resisting frames. To investigate the seismic performance, time history analysis was conducted including 22 pairs of far-field ground motion records from FEMA P695. The results reveal that CCB systems show an almost similar drift pattern with CB frames, especially in the 12-story frame. In general, adding cable cylinder braces has increased the first-story column shear more than regular cable braces, especially in the 4-story frame. However, the maximum compression force of the adjacent column was lowered in the CCB frames than that of the CB models. The base shear force was improved notably in CB frames, while the CCB system had relatively identical base shear demand to the OFs.

Particulate mass migration and mixing in cylindrically contained explosions

To explore particulate movement near the plasma of chemical explosions, rugged tracer particles were placed within and on the exterior of metal charges and electrically detonated. The particles were collected on/in the porous walls of plastic cylinders at diameters that correlated to the plasma width during different phases of the explosion. The particles’ positions were determined by Boolean logic analysis of their luminescent intensity. The cylinders which caught particles from the initial phases of the explosion retained placement information, while wider cylinders showed uniform mixing. These results/analysis methodology can help improve the understanding of particulate mixing in harsh environments.Graphical abstract

Developing a platform for Fresnel diffractive radiography with 1 μm spatial resolution at the National Ignition Facility.

An x-ray Fresnel diffractive radiography platform was designed for use at the National Ignition Facility. It will enable measurements of micron-scale changes in the density gradients across an interface between isochorically heated warm dense matter materials, the evolution of which is driven primarily through thermal conductivity and mutual diffusion. We use 4.75keV Ti K-shell x-ray emission to heat a 1000 μm diameter plastic cylinder, with a central 30 μm diameter channel filled with liquid D2, up to 8eV. This leads to a cylindrical implosion of the liquid D2 column, compressing it to ∼2.3 g/cm3. After pressure equilibration, the location of the D2/plastic interface remains steady for several nanoseconds, which enables us to track density gradient changes across the material interface with high precision. For radiography, we use Cu He-α x rays at 8.3keV. Using a slit aperture of only 1 μm width increases the spatial coherence of the source, giving rise to significant diffraction features in the radiography signal, in addition to the refraction enhancement, which further increases its sensitivity to density scale length changes at the D2/plastic interface.

Marginal integrity of composite resin restoration in class I cavities prepared by hydro-abrasion

Aim To evaluate and compare the marginal integrity of composite resin restorations made by two different preparation techniques: conventional drill and hydro-abrasion. Materials and methods Forty extracted human premolars with simple occlusal caries were used. The teeth were fixed with sticky wax to the base of plastic cylinder. The cylinder was filled with self-curing acrylic resin so that only root was embedded within the self-curing acrylic resin. The teeth were randomly divided into two main groups (n = 20) according to the preparation technique. Group I: class I cavity preparation was done by the conventional drill method using a #245 Carbide bur and contra angle high-speed hand piece with water coolant. Cavity design was restricted to remove caries with no undercuts, and no beveling. Group II: class I cavity preparation was done by Aquacut Quattro air hydro-abrasion unit which uses a gamma irradiated aluminum oxide particle as abrasives (29 μm), cutting fluid and a hand piece of 0.6 mm diameter tip. The preparation in both groups was restored by the same composite resin (Grandio) and adhesive systems (Futurabond U) following the manufacturer's instructions. All specimens were thermocycled. Impressions for each tooth was made using a polyvinyl Siloxane material. The impressions were then poured with epoxy resin. These replicas were examined under scanning electron microscope. Scanning electron microscope photographs of tested samples were used for the gap evaluation. Results It was found that, group I recorded higher mean value of marginal gap length (157.57 ± 35.15 μm) than group II that recorded (69.55 ± 20.02 μm). Also, group I recorded higher mean value of marginal gap length ratio (10.72 ± 2.47) than group II that recorded (7.44 ± 2.69). Conclusion Conventional drilling technique was faster than the hydro-abrasion technique for cavity preparation. Hydro-abrasion technique showed more marginal adaptation than conventional drilling technique.

Influence of Digester Height-to-Diameter Ratio on Biomethanation of Market Vegetable Wastes

Biogas digesters are used to produce methane gas from organic wastes such as vegetable wastes. They come in different sizes and designs depending on available space, costs, type of operations and other considerations. Fifteen types of vegetable wastes from Cagayan de Oro markets were anaerobically digested in a batch-type digester with cow manure as inoculum at ambient conditions for 40 days. Five 1-L plastic cylinders with different height-to-diameter ratios (0.77, 1.08, 1.58, 1.93 and 2.80) were used as digesters to determine the effect of digester height-to-diameter ratio on methane production using these vegetable wastes. Results revealed that the digester with the lowest height-to-diameter ratio produced the most methane (53.3%) after the retention time. In contrast, the digester with the highest height-to-diameter ratio yielded the least methane concentration (46.8%). This indicated that there was an inverse relationship between the ratio and the methane production of vegetable wastes mixed with cow manure. Although the results suggested a minor influence, the statistical analysis presented an insignificant influence of the height-to-diameter ratio on the biomethanation of vegetable wastes.

Mechanical Analysis of Frozen Wall with Trapezoidal Temperature Field Distribution Based on Unified Strength Theory

In order to study the elastic–plastic stress field distribution of a double-row-pipe frozen wall, the temperature field of the double-row-pipe frozen wall is equivalent to a trapezoidal distribution, and the frozen wall is regarded as an elastic–plastic thick-walled cylinder with functionally gradient material (FGM) characteristics in the radial direction. Considering that the elastic modulus and cohesion of the frozen wall material change linearly with the radius, the elastic–plastic analysis of the frozen wall is carried out based on unified strength theory. The analytical solutions of the elastic–plastic stress field distribution, the elastic ultimate bearing capacity, the plastic ultimate bearing capacity, and the relative radius of the plastic zone of the frozen wall are derived. The analytical solution is calculated based on the engineering case and compared with the numerical solution obtained based on COMSOL. At the same time, the influence of strength theory parameters on the mechanical properties of heterogeneous and homogeneous frozen walls is analyzed. The results show that the analytical solution and the numerical solution are in good agreement, and their accuracy is mutually verified. The external load on the frozen wall of the selected layer is greater than its elastic ultimate bearing capacity and less than its plastic ultimate bearing capacity, which indicates that the frozen wall is in a safe state of stress. The radial stress increases with the increase in the strength theoretical parameter b and the relative radius r, the tangential stress increases with the increase in the strength theoretical parameter b, and first increases and then decreases with the increase in the relative radius r. The larger the strength theoretical parameter b, the smaller the relative radius of the plastic zone of the frozen wall. The strength theoretical parameter b increases from 0 to 1, the elastic ultimate bearing capacity and plastic ultimate bearing capacity of the heterogeneous frozen wall increase by 33.3% and 40.8%, respectively, and the elastic ultimate bearing capacity and plastic ultimate bearing capacity of the homogeneous frozen wall increase by 33.3% and 41.0%, respectively. Therefore, considering the influence of intermediate principal stress, the potential of materials can be fully exerted and the ultimate bearing capacity of frozen walls can be improved. This study can provide theoretical reference for the design and construction of frozen wall.

Effect of different growing media on selected growth performance parameters of Raphanus pugioniformis and Raphanus raphanistrum

Raphanus raphanistrum and R. pugioniformis (Brassicaceae) are wild radishes, native to the Eastern Mediterranean region. This study aimed to evaluate the effect of growing soil media (perlite, sand, and terra rossa) on the growth performance of two Raphanus species. For this, seeds of the selected species were germinated and seedlings were transferred to plastic cylinders, filled with growing soil media. At harvest, various growth parameters including shoot length, shoot fresh weight, shoot dry weight, root length, root fresh weight, and root dry weight were determined. Root and shoot fresh and dry weight, before and after oven dry for 24 h at 70 °C was measured. Results of the study revealed statistically significant differences (P value ≤ 0.05) among the various studied growth parameters for the selected Raphanus species and are affected by different growing media including types of soil and growing time (days after potting from 33 to 78). After 33 days of potting, the average shoot length for R. pugioniformis was found 6.6, 8.0, and 8.6 cm in terra rossa, sand, and perlite growing media respectively. On the other hand, the fresh (0.8, 1.6, and 2.5g) and dry (0.25, 0.48, and 0.72g) shoot weight for R. pugioniformis was reported in terra rossa, sand, and perlite soil media respectively. From the results of the study, it can be concluded that among the tested growing media, perlite growing medium is the best medium for the growth of both studied Raphanus species. This study demonstrated that the three studied growing media affected all the growth performance parameters of both Raphanus pugioniformis and Raphanus raphanistrum differently.