Lining Materials Research Articles

Meko podlaganje imedijatne totalne proteze - prikaz slučaja

Introduction: With the placement of dental implants in edentulous patients, creating and adapting immediate dentures is crucial to allow patients to perform basic physiological functions during the osseointegration period without affecting implant healing. This report presents a case of direct soft lining of immediate complete dentures following implant placement. Case Report: Six dental implants were inserted in the upper jaw, while the patient retained natural teeth in the lower jaw. An immediate complete denture was fabricated and adjusted for the upper jaw. The prosthesis base was prepared and processed to accommodate soft lining material. Adhesive was applied to the prepared base, followed by silicone application for soft fitting onto the prosthesis base, which was then inserted into the patient's mouth. After three minutes, the denture was removed, and soft lining treatment of the immediate complete denture was completed. Conclusion: Direct soft lining facilitated patient adaptation to the immediate prosthesis and supported safer healing and osseointegration until definitive work could be completed. The addition of a soft silicone layer reduced pressure on the residual alveolar ridge and improved adhesion of the immediate prosthesis.

The Effect of Different Finish Line Designs and Material Types on the Periodontal Response of Single Crown Restoration: A 3-year Follow-up Study

Purpose: Different restorative materials and marginal finish lines may contribute to periodontal inflammation, in spite of patients' proper oral hygiene habits. The aim of this study was to evaluate the effect of different finish line designs and restorative materials on periodontal health. Materials and Methods: In this retrospective clinical study, the periodontal clinical parameters of 450 crown restorations fabricated with different finish line designs (chamfer, shoulder, knife-edge) and different materials (Metal-ceramic, Zirconia, Glass-ceramic) were evaluated at baseline and at 12th, 24th and 36th months after the cementation. The data were analyzed with Repeated Measures ANOVA and post hoc least significant difference tests were performed (α=.05). Results: Periodontal clinical parameters significantly increased during the 36-month follow-up period. The marginal finish line and material type had no significant effect on the probing depth and gingival index scores. The highest plaque index scores were observed in zirconia restorations with knife edge finish lines at the 36th month after crown placement. Conclusions: The periodontal health of the prepared tooth was negatively affected by the increased follow-up duration regardless of the marginal finish line design and material type. The clinicians should consider the favorable effect of the glass-ceramic crown restorations with a chamfer finish line on the plaque control for long-term success.

An assessment of the impact of L.Salvadora persica and G.Tea on the surface roughness and hardness of heat-cured acrylic-based denture soft liners.

Background: Soft denture liners are a type of dental prosthesis that functions as a cushioning material, alleviating the stress induced by the act of chewing. They offer relief to persons who encounter discomfort when wearing complete or partial dentures, particularly when these dentures are situated on rigid surfaces that support the denture. The objective of this study: is to assess the effects of including L.Salvadora persica. and green tea (G.Tea) extract powders on the surface roughness and hardness characteristics of acrylic-based soft liners. Materials & Procedures: 30 specimens were constructed using wax molds and acrylic-based heat-cured denture soft lining material. The standard curing procedure was used. The samples were separated into three equal groups: group A, the control group, with no additives in the soft-liner material; group B, with 5.12% weight percept L.salvadora persica extract powder; and group C, with 5.12% weight present green tea (G.Tea) extract powder. The samples were then prepared for surface hardness and roughness testing. Results: The results revealed that there was a non-significant rise in the mean values of surface roughness for both group B and group C, group B having the highest mean values followed by group C. When compared to the control group, the results showed a considerable rise in the mean values of surface hardness in group (B), which had the highest mean value for surface hardness, followed by group (C). Conclusion: The results of this study indicate that the incorporation of L.salvadora persica at a concentration of 1.024g and green tea (G.Tea) extract powders at a concentration of 1.024g shown a positive impact on the surface hardness of denture soft lining materials

FEMININE ROMANTIC STYLE DENGAN APLIKASI SONGKET BALAI PANJANG PAYAKUMBUH

Feminine romantic is one of basic fashion styles that is synonymous with the impression of a dress that is calm, sweet, and dominated by soft design lines, the colors used in this clothing style are synonymous with soft colors, and the use of materials such as silk, borkat, crepe, silk and chiffon. To realize the feminine romantic style in clothing creation, the Balai Panjang songket was chosen as a medium applying this style to become ready-to-wear clothing. Clothing that designed is aimed at teenage women aged 19-25 years, and adult women aged 26-35 years, to make it easier for users to choose clothes for work, travel, recreation, and parties. The purpose of creating this clothing is to be able to design clothing with the theme of feminine fomantic style with the Balai Panjang songket application, then demonstrate it in the form of a fashion show, so that the designed work can be socialized to general public. Clothing with a type of feminine romantic style has never been made with the Balai Panjang Songket, so with the creation of this work it can be become a reference for the creation of work of feminine romantic style for the future. In creating the work of this final project, the artist uses creation methods such as preparation, design, embodiment to the presentation of the work carried out. The process of creating clothing uses standard boutique sewing technique, namely by using a lining material, so that the clothes are the resulting impression give a neat, and clean. The results of the design source ideas for feminine romantic style are in the form of ready to wear, ready to wear deluxe and haute couture clothing.

Computational fluid dynamics and artificial neural networks for modelling lined irrigation canals with low‐density polyethylene and cement concrete liners

AbstractThis study numerically investigated the lining effect on the discharges and seepage losses of five reaches which belong to the El‐Sont Canal, Asyut, Egypt, using FLOW‐3D and Slide2 models, respectively. Two lining materials were considered, cement concrete (CC) and CC with low‐density polyethylene (LDPE) film. A cost analysis was performed to explore the feasibility of the proposed lining materials. Moreover, a parametric study was conducted by the Slide2 model to investigate the effect of canal geometry and liner properties on seepage losses. An artificial neural network (ANN) model was developed based on the Slide2 model scenarios to estimate the seepage losses from lined irrigation canals. The results showed that reach the discharge calculated from the FLOW‐3D model increased by 92%–97% and 149%–156%, while the calculated seepage losses from the Slide2 model decreased by 81%–87% and approximately 97% under CC and CC with LDPE film liners, respectively. Cost analysis revealed that the overall cost of CC with LDPE film was higher by 14% than CC. Relying on the importance of saving irrigation water and conveying water to the last reaches, CC with LDPE film is recommended for lining irrigation canals. A parametric study showed that the seepage losses were reduced by more than 96% when the ratio between liner and soil hydraulic conductivities was less than 0.01. A thick liner could maximally decrease the seepage losses by 68%, regardless of the canal geometry. As the developed ANN model showed a close agreement with the Slide2 results with coefficient of determination (R2) and mean squared error values of 0.99 and 0.05, respectively, the ANN model is recommended as a robust and rapid tool for estimating seepage losses from lined irrigation canals.

A method to improve the barrier performance of flexible riser internal pressure sheath—Heat transfer experiment and simulation

AbstractA considerable amount of acidic gas penetrates into the annulus between the internal pressure sheath and the outer protective sheath during the service of flexible risers, which will inevitably lead to corrosion of the metal functional layer. Many researchers have modified nanocomposites from the mass transfer perspective to reduce the materials' permeability coefficient. While permeation is an integrated process of heat and mass transfer process, heat distribution directly impacts gas permeation. Herein, the thermal conductivity of flexible riser liner materials is predicted for the first time by a combination of molecular dynamics and experiments, and then the radial temperature distribution under different seawater temperatures and internal fluid temperatures is investigated by finite element analysis. Finally, the effect of temperature distribution on the permeation coefficient was analyzed. The results demonstrate that the thermal conductivity can be predicted by molecular dynamics simulation, and the thermal conductivity of (polyvinylidene difluoride) PVDF/TiO2 decreases, while the thermal conductivity of PVDF/carbon nanotube (CNT) increases compared with pure PVDF. The temperature distribution of the internal pressure sheath material decreases when condensate water is present. As the fluid temperature rises from 30 to 110°C, the maximum increase ratio in the permeability of PVDF/CNT over PVDF increased from 3.6% to 14.8%, and the maximum decrease ratio of PVDF/TiO2 permeability coefficient compared with PVDF is from 1.2% to 4.6%. The results present a new idea to improve the barrier properties of materials by decreasing thermal conductivity.

Ion release, biocompatibility, and bioactivity of resin-modified calcium hydroxide cavity liners

BackgroundThe placement of liners near the pulp area is essential for therapeutic effects and maintaining pulp health while stimulating the formation of tertiary dentin. This in vitro study aimed to evaluate the calcium release, pH, biocompatibility, solubility, and bioactivity of three resin-modified calcium hydroxide cavity liners.MethodsThe disc specimens of each cavity liner were prepared using polyethylene molds of 7 mm in diameter and 2 mm in height (n = 10). Three light-cure liners evaluated include Ultra-Blend Plus (UB), Base-it (BI), and Master Dent (MD). The samples were then immersed in flasks containing 10 mL of distilled water. Calcium ion release, pH, and solubility were evaluated in two weeks of incubation. The cytotoxicity of extracts adjacent to the specimens was evaluated by MTT assay using NIH/3T3 cells after 1, 3, and 7 days of incubation. The ability to induce the nucleation of calcium phosphates (CaPs) after 28-day immersion in a simulated body fluid was investigated by SEM-EDX analysis. Statistical analysis was performed using ANOVA, Kruskal-Wallis, and repeated measures tests at the significant level of 0.05.ResultsThere was a significant difference in the release of calcium ions among the three liners investigated on days 1, 7, and 14 (p < 0.05). UB liners exhibited a significantly higher amount of calcium release than the other two liners, followed by BI, and MD. On day 1, there was no significant difference in the average pH among the three liners. However, after day 7, the MD liner showed a significant decrease in pH compared to the other two liners. BI liner demonstrated the highest level of biocompatibility, followed by the MD and UB liners. UB showed a high calcium release, solubility with no alkalizing activity, and the formation of more mature Ca-rich apatite deposits than the other two liners.ConclusionBased on the results of this study, the cavity liner material’s performance is material dependent. It can impact ion release, biocompatibility, and bioactivity which are important factors to consider in clinical practice. Further studies are needed to investigate the long-term effects of different liner materials on oral tissues.

STUDY OF THE AIR PERMEABILITY INDICATOR OF A PACKAGE OF MATERIALS OF THERMAL CLOTHING FOR CHILDREN WITH A DIAGNOSIS OF CP

This article reports the results of breathability tests on upper materials, nonwoven insulation materials, lining materials, and material packs. The importance of air permeability values for packages of materials of thermal protective clothing for children diagnosed with cerebral palsy (CP) is substantiated. Objects and methods for studying the air permeability of materials are defined and described. The method according to State Standard ISO 9237–2013 was used to assess the properties of air permeability of materials. A method for calculating the predicted values of the air permeability of packages of materials is also given. The article analyses the results of air permeability of packages of materials obtained both theoretically and experimentally. The article compares the values of the air permeability of the packages of materials with the previous study of the packages of materials on the total thermal resistance. Conclusions are drawn about the requirements for air permeability of packages of materials for thermal protective clothing for children with cerebral palsy.

Evaluating the Potential of Multi-Walled Carbon Nanotube-Modified Clay as a Landfill Liner Material.

In this paper, the feasibility of multi-walled carbon nanotube (MWCNT)-modified clay as a landfill liner material is investigated. Experiments were conducted on the modified clay with 0.5%, 1%, and 2% MWCNTs. The effects of the MWCNTs on the compaction characteristics, permeability coefficient, stress-strain curve, peak deviation stress, shear strength parameters (internal friction angle and cohesion), microstructures, and adsorption performance of the clay were analyzed. The results showed that the optimum moisture content (OMC) increased from 16.15% to 18.89%, and the maximum dry density (MDD) decreased from 1.79 g/cm3 to 1.72 g/cm3 with the increase in MWCNTs. The permeability coefficients firstly fell and then gradually rose as the MWCNTs increased; the minimum permeability coefficient was 8.62 × 10-9 cm/s. The MWCNTs can also effectively increase the peak deviation stress of the clay, and at the maximum level, the peak deviation stress was increased by 286%. SEM images were processed using the Pore and Crack Analysis System (PCAS), and the results showed that the appropriate amount of MWCNTs could fill the pores and strengthen the clay structure. The effect of the MWCNT-modified clay on the adsorption performance of common heavy metal ions Cd2+, Mn2+ and Cu2+ in landfill leachate was analyzed by batch adsorption tests. The maximum adsorption capacities (Qmax) of Cu2+, Cd2+ and Mn2+ in the 2% MWCNT-modified clay were, respectively, 41.67 mg/g, 18.69 mg/g, and 4.97 mg/g. Compared with the clay samples without MWCNTs, the adsorption properties of Cu2+, Cd2+, and Mn2+ were increased by 228%, 124%, and 202%, respectively. Overall, the results suggest that MWCNT-modified clays have the potential to be suitable barrier materials for the construction of landfills.

Buried Service Line Material Characterization Using Stress Wave Propagation: Numerical and Experimental Investigations

Buried Service Line Material Characterization Using Stress Wave Propagation: Numerical and Experimental Investigations

Shape manipulation of a rotating liquid liner imploded by arrays of pneumatic pistons: Experimental and numerical study

Shaping the inner surface of a rotating, imploding liquid metal liner as it compresses a magnetised plasma target is an important aspect of the Magnetised Target Fusion (MTF) scheme pursued by General Fusion. Reduced-order modelling has shown that the liner's inner surface shape can be manipulated during the implosion by spatially varying the amplitude and timing of pressure applied at the liner's outer surface. A sub-scale apparatus was constructed to investigate this concept, using water as the liner material. A simplified axisymmetric model of this apparatus was also developed using OpenFOAM software. Experimental pressure and rotational speed were used as inputs to numerical simulations. Very good agreement between numerical and experimental liner trajectories was obtained for a wide range of implosion parameters. Data analysis confirmed an initially cylindrical inner liner surface can be shaped and the shaped surface remains symmetrical to radial compression ratios of at least 7:1, despite driving the implosion using pneumatic piston arrays. Furthermore, experiments demonstrated suppression of Rayleigh-Taylor instability for shaped implosions by using liner rotation. This is significant, as literature only confirms this suppression for cylindrical implosions. These results increase confidence in simplified numerical modelling as a predictive tool for designing MTF machines.

Interaction of Heavy Metals with Plastic Contaminated Soil

Microplastic (MP) contamination is a threat to soil and groundwater system. Disintegration of used plastic products under exposure to solar radiations, application of sewage sludge to the soil, plastic mulching in agricultural activities leads to the formation of microplastics in significant amounts in soil. Hence there is a need from the geo environment engineering perspective on microplastic contamination in soils. Landfills and industrial areas have microplastic pollution in abundance. The presence of microplastic may alter the behaviour of liner material and surface soil in terms of heavy metal retention capacity, shrinkage, permeability and various other properties. In the present study, the soil is artificially polluted with shredded polypropylene (Pp) fragments from single use facial mask which is extensively being used in post COVID-19 situation. Heavy metals such as Lead, Nickel, Copper and Zinc at different concentrations similar to an industrially polluted soil is applied to the plastic contaminated (Pc) and normal soil. The filtrates from the test batches are studied for Total Dissolved Solids (TDS) and concentration of heavy metals using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). The obtained results concluded that plastic pollution significantly varied leached out heavy metals concentration to a maximum of 4.9 times that of normal soil. The TDS of the filtrate collected from plastic polluted soil varied by 31.29%.

Experimental Investigation of Red Soil Blended With Bentonite and Lime as a Landfill Liner

To control the migration of contaminants generated from the leachate, the liners are used in landfills. Compacted clay liners are widely used as liner materials due to the low value of hydraulic conductivity and large attenuation capacity. In the present work, an experimental study on red soil which is locally available is amended with bentonite use as a liner material for efficient leachate containment in landfills. The primary objective of this work is to determine the geotechnical properties of red soil blended with bentonite as a material for liners. The clay liners performance primarily depends on hydraulic conductivity. The hydraulic conductivity of the red soil is higher than the recommended limit (i.e.&gt;10-7cm/s). Commercially available bentonite was blended with red soil to decrease the hydraulic conductivity. The permeability tests and falling head tests were conducted on 5%, 10%, 15%, and 20% bentonite by weight blended with red soil to evaluate hydraulic conductivity. From the experimental studies, it is clear that the red soil blended with 15% bentonite has a hydraulic conductivity value less than the requirements of landfill clay liner(i.e.&lt;10-7cm/s). However, the Compressive Strength (CS) of blended red soil with 15% bentonite was less than 200 kPa, which is less than the minimum CS required for liner material. Lime was added to enhance the CS of the soil mixture and further studies were carried out. Swelling behavior is the major problem that is to be addressed during and after the construction of landfills. This study also presents the swelling behavior of red soil blended with bentonite and other additives.

DEVELOPING DISCOVERY LEARNING-BASED STUDENT WORKSHEET ON THE EQUATION OF A STRAIGHT LINE MATERIAL

This research aimed at developing and producing valid, practical, and effective Discovery learning-based student worksheets on Equation of a Straight Line material. Research and Development with the ADDIE (Analysis, Design, Development, Implementation, and Evaluation) model. This research was administered at State Junior High School 18 Pekanbaru. The subjects of this research were validators who were lecturers, teachers, and students at State Junior High School 18 Pekanbaru. The object was a Discovery learning-based student worksheet on Equation of a Straight Line material. The data were qualitative and quantitative. The instruments used were a questionnaire sheet and posttest questions. The research findings showed that the Discovery learning-based student worksheet developed was in a very valid category with a percentage of 86.37%. It was very practical for the small group, with a percentage of 84.4%, and it was very practical for the limited group, with a percentage of 85.3%. Based on the posttest result, the score of tobserved was higher than ttable, 4.007&gt;1.667, with dk=24 and 5% or 0.05 significant level. So, Ha was accepted, and H0 was rejected. It meant there was a difference in learning achievement between experimental and control groups. The effectiveness of student worksheet use on Equation of a Straight Line material could be identified from the dengan menunjukkan posttest mean scores of experimental (83.54) and control (75.2) groups.

Impingement testing of total hip replacements according to ASTM F2582 – Implant wear, resistance to damage and acceptance criteria

ObjectivesThe aim of this study was to determine the resistance to impingement damage of three different artificially aged UHMWPE materials used for total hip joint replacement. The results obtained can be used as a basis for an acceptance criterion for testing according to ASTM F2582-20. MethodsThree different polyethylene liner materials, standard polyethylene (UHMWPE), moderately crosslinked (XLPE) and vitamin E stabilized crosslinked (XLPE-VE) polyethylene of the same design and manufacturer were tested up to one million impingement cycles according to ASTM F2582-20. The liners were artificially oxygen aged for two and three weeks according to ASTM F2003-02. The wear volumes of the liner, acetabular shells, and hip endoprosthesis stems were determined. Each of the six impingement test groups consisted of three samples. For each test group, a reference group was subjected to the same conditioning and loading conditions but without impingement between the hip stem and the liner. The force needed to disassemble the liner from the acetabular shell (push-out force) was determined according to ASTM F1820-22 for the test and the reference groups. ResultsXLPE and XLPE-VE polyethylene groups showed less impingement wear when compared to the standard UHMWPE material. Similarly, the protective function of the liner against direct metal-on-metal contact was greater, resulting in less wear on the acetabular shell and the stem neck. The three weeks aged standard UHMWPE group showed early onset of fatigue delamination wear. The push-out values remained unchanged for all XLPE liners and the 3-week aged XLPE-VE liners. The aged UHMWPE liners showed low push-out strength due to component shrinkage caused by aging in combination with the tapered fixation used for this specific design. SignificanceThe largest polyethylene wear volume measured of XLPE and XLPE-VE polyethylene aged for two and three weeks was 15.05 mm³ (SD 0.56 mm³). The corresponding metal wear volume was 1.23 mm³ (SD 0.19 mm³) for the acetabular cup and 1.33 mm³ (SD 0.20 mm³) for the stem neck. Those values can support the definition of an acceptance criteria for impingement testing. The results of the push-out test required by ASTM F2582-20 should be evaluated with respect to geometry changes caused by aging. The protective effect of the polyethylene liner against metal-on-metal contact should be considered in the implant design phase in order to avoid implant failure due to metal debris.

Phosphate-bonded refractories in hydrogen containing atmosphere

In the transition to a CO2-neutral industry, traditional carbon fuel-based systems must be replaced by sustainable fuel systems such as hydrogen. This change implies a different atmosphere during the operation at high temperature, which is a big challenge for refractory lining materials. This study focuses on four different phosphate-bonded refractories, which are generally characterised by fast drying times, adequate refractoriness, and excellent abrasion and slag resistances. Two phosphate-bonded industrial refractory masses, one based on corundum and the other on fireclay, are tested under corrosive conditions. Two model systems are considered to provide a fundamental view of the behaviour. These focus on smaller grain sizes, reduced silica content and proportionally contain higher amounts of different phosphate-based binders. The first model system contains mainly magnesia and is bound by sodium polyphosphate. The other consists of alumina and is bonded with monoaluminium phosphate. All materials are exposed in a dilute, 9Ar 1H2, hydrogen atmosphere at various temperatures and holding times.Corrosion experiments up to 1500 °C have been carried out using a tube furnace with the above conditions. The microstructure, and in particular the binder phase, was characterized by SEM and EDS. Microstructural components undergoing reaction or loss will be identified and their behaviour and movement in the system will be considered. Particular attention is paid to the phosphorus components, their possible reduction and their influence on the binder phase.

Improvement of earth-to-air heat exchanger performance by adding cost-efficient soil

Geothermal research advances earth-to-air heat exchanger (EAHE) technology, offering promising air conditioning solutions for all buildings. Our study targets improved energy efficiency for the EAHE system, focusing on cost-effective approaches to enhance its technical, economic, and environmental performance. The thermal performance and economic viability of the EAHE system hinge on the thermal characteristics of the surrounding soil. The EAHE model features a single pipe with dimensions of 0.5 meters in diameter, 1 centimeter in thickness, and 10 meters in length. These pipes are strategically placed at depths of 1 meter, 2 meters, 3 meters, and 4 meters below the ground's surface. To optimize heat exchange efficiency while minimizing pipe length, we propose using a secondary soil material with high thermal conductivity as a lining for the EAHE pipes. Our innovative approach carefully considers the economic and environmental aspects of various lining materials, resulting in optimal performance at a minimal cost. Extensive simulations and data analysis lead us to identify an ideal lining material, naturally available, environmentally friendly, and cost-effective, ensuring peak efficiency. Our investigation assesses the EAHE system's thermal performance for both summer cooling and winter heating, demonstrating its effectiveness across seasons. This research underscores the case for utilizing EAHE systems during winter and autumn for heating and during spring and summer for cooling. Our findings are supported by robust performance indicators, confirming the effectiveness of our approach.

Android-based Didactical Design for Learning Lines and Angles: An Interpretive Didactical Design Research

Lines and angles are quite important mathematical concepts. This is proven because lines and angles cannot be separated in life. However, lines and angles actually become a problem/obstacle in the classroom. The purpose of this research is to determine the description of students' learning obstacles in the material on lines and angles for class VIII MTs NW Pringgajurang, then a didactic design for learning lines and angles will be prepared. The research design used is didactical design research-interpretive. The participants in this research were Class VIII students at MTs NW Pringgajurang with an age range of 12 to 14 years. The researcher is the main instrument in this research, with several additional instruments such as tests for understanding lines and angles, student biodata, interview guides and didactic designs for lines and angles. The data analysis technique used in this research is thematic data analysis. This thematic analysis is used as a basic foundation for the analytical process in qualitative research, by paying attention to the results of the data collection carried out. The results of the research show that students experience learning obstacles with ontogenic psychological and ontogenic conceptual types. With this Android-based didactic design, it is hoped that it will be able to minimize barriers to students' learning on line and angle material at MTs NW Pringgajurang.

Effect of Microwave Energy Disinfection on Roughness of Soft Lining Material

Introduction: Soft lining material enhance the patient’s comfort, its rough surface affect oral health, the risk with soft reliners was difficult hygienic maintenance, sterilization by microwave method more favor compared with chemicals disinfections. Objective to study the effect of disinfection by microwave irradiation at different exposure time on surface roughness of long-term soft-liner material. Material and Methods: 45 Specimens of long-term soft liner were made in the form of square metal shaped pattern. The preparation of mould was done by conventional procedures according to manufacture instruction and divided into three groups: GroupA control (without disinfection), Group B daily disinfection by microwave for 5min at 650W and GroupC daily disinfection by microwave for15min at 650W. The specimens were irradiated daily for 15 days (both group B&amp;C). Roughness measurement were made for three groups by profilometer device and analyzed by ANOVA ‘test. Result show that high mean value surface roughness of long term soft liner after expose to microwave disinfection for 15 min(Group C), and low mean value before expose to microwave disinfection(Group A), there were highly significant differences (P&lt;0.01) among tested groups and there was no significance difference (p&gt;0.05) between control Group with (Group B) 5 min disinfection, while the difference was significance (p&lt;0.05) between (Group C )15 min disinfection with : (Group B) 5 min disinfection and with (Group A )control group. Conclusions: the roughness of long-term soft-liner material was not adversely affected by microwave disinfection at 5 min, there was no significant differences with control group while adversely affected by microwave disinfection at 15 min, there was significant differences with control group also with group 5 min disinfection.

BEHAVIOURS OF NATURAL AND SPOROSARCINA PASTEURII (BACILLUS PASTEURII) AS A LINER

The enhancement of sandy soil as a liner and cover material for usage as waste containment facility was taken into consideration in this work using Bacillus pasteurii to activate the microbial-induced calcite precipitation (MICP) process. This study aimed at determining the physical properties of SPOROSARCINA PASTEURII (BACILLUS PASTEURII) as a liner. The study's sandy soil, which had a natural moisture content of 8.56%, came from Wudil Local Government Area in Kano State, Nigeria. Stepped Bacillus pasteurii suspension densities of 0 cells/ml, 1.5 x 108 cells/ml, 6 x 108 cells/ml, 12 x 108 cells/ml, 18 x 108 cells/ml, and 24 x 108 cells/ml were applied to the sandy soil. The Atterberg's limit test result, which showed that the soils were nonplastic, was used to determine the index properties of the soil. The soil was classified as A-3(0) and SP soil, respectively, according to the AASHTO and USCS classification systems. The specific gravity decreases with increase in Bacillus pasteurii suspension density