Study of Clayey Soils with Nonwoven Geotextiles as Liners in Landfill Stabilization

Landfills are highly complex, well-engineered series of cells in or above the ground level. Soil stabilization is the alteration of soils to enhance their physical properties. Landfill stabilization increase the shear strength of soil thus improving the load bearing capacity. Geotextiles are permeable fabrics which, when used in association with soil, have the ability to separate, filter, reinforce, protect or drain. All have a wide range of applications and are currently used to advantage in many civil engineering applications including roads, airfields, railroads, embankments, retaining structures, reservoirs, canals, dams, bank protection and coastal engineering. Typically made from polyester, they are classified into woven, needle punched, heat bonded. nonwoven geotextiles are manufactured by bonding materials together made of synthetics and used in separation applications. Non-woven geotextiles have more gaps of plastic membrane and right choice where pooling water is major concern i.e. drainage systems. In this present study, different geotextiles gives varying advantages. The permeability of the soil can be reduced to desired coefficient and also increased based on the type of geotextile used. The angle of shearing resistance (angle of internal friction) would be lower than that of the unreinforced soils. The performance of the geotextiles depends upon the index properties of the soil.

Design of 3D Structure Membrane for the Increased Sensitivity in Enzyme Linked Immunosorbent Assay (mELISA)

The Enzyme Linked Immunosorbent Assay (ELISA) technique has been widely used for the identification and quantification of biochemical markers. The typical ELISA requires a number of washing steps to eliminate the unbound proteins which sometimes cause the desorption of protein due to their weak bonding between protein and well plate. In this study, we have developed a meshed type of plastic membrane in order to increase the reliable binding efficiency between proteins and the membrane surface, and to provide easy steps of washing. The use of our developed solid membrane has significantly increased the binding capacity of the biomolecules because this membrane ELISA (mELISA) provides 3D binding surfaces which increases the surface area when compared to the conventional 2D surface well plate. The columns were pretreated to form a self-assembled layer (SAM) on the surface for the stable conjugation of a target antibody. The SAM-coated membranes could be stored for one month without any further deterioration of stability. The measured optical density (O.D.) shows a 1.2-fold increase in IgG antigen (25 μg/mL) from the plastic membrane as compared with the conventional ELISA method. The concentrations of thyroid stimulating hormone were also monitored using the mELISA method and it shows good linearity against the concentrations.

Utilization of Vacuum-Formed Plastic Membranes for the Production of Lightened HPC Panels

This paper describes the utilization of vacuum-formed plastic membranes for the production of lightened panels made of high-performance concrete with technical textile reinforcement. The use of vacuum-formed plastic membranes is aimed to reduce the cost and increase the efficiency of production of concrete elements with highly profiled surface. Studded plastic membrane is cheap alternative to silicone or steel and while it provides slightly lower precision of manufacturing it surpasses especially the steel alternative in the terms of demoulding, since it has not sharp edges and can be easily bended.Second part of the article focuses on the limitations given by the lightening and the approach to reduce them while maintaining the reduction of material usage. The cross-section weakened by lightening in comparison to the un-lightened specimens leads to earlier development of cracks in concrete matrix and lower ultimate bending strength caused by shear failure of the lightened cross-section. The development of cracks in concrete matrix cannot be easily controlled while maintaining the same level of lightening but by addition of another layer of the reinforcement it is possible to achieve similar ultimate bending strength as in the case of elements with full cross-section and same thickness.

Potentiometric detection of low-levels of sulfamethazine in milk and pharmaceutical formulations using novel plastic membrane sensors

Novel potentiometric sensors for selective screening of sulfamethazine (SMZ) in pharmaceutical preparations and milk samples are reported. The sensor membranes were made from PVC matrix doped with magnesium(II)-, manganese(II)- and dichlorotin (IV)-phthalocyanines as ionophores and aliquat-336 and nitron/SMZ ion-pair complex as ion exchangers. These sensors revealed fast, stable and near-Nernstian anionic response for the singly charged sulfamethazine anion over the concentration range 10-2 - 10-5 M. The sensors exhibited good selectivity towards SMZ over most known anions, excipients and diluents commonly added in drug preparations. Validation of the proposed methods was demonstrated via evaluating the detection limit, linear response range, accuracy, precision (within-day repeatability) and between-day-variability. The sensors are easily interfaced with a double channel flow injection system and used for continuous monitoring of SMZ in drug formulations, spiked milk samples and biological tissues. The method offers the advantages of design simplicity, results accuracy, and automation feasibility.

Depth profiling X-ray photoelectron spectroscopy and atomic force microscopy of Cd(ii)- and Pb(ii)-selective electrodes based on nano metal sulfides

Nanoparticles of CdS and PbS as ionophres for plastic membrane metal cations electrodes.

A one-step strategy for ultra-fast and low-cost mass production of plastic membrane microfluidic chips

A PE membrane and an EVA-coated PET membrane are piled up. When pressed by a heated non-stick stamp, the two membranes bond together, and the PE membrane spontaneously rises at the area not pressed, forming flexible microchannels within 12 seconds.

PENENTUAN KADAR OKSIGEN TERLARUT MENGGUNAKAN SENSOR POLAROGRAFI BERMEMBRAN PLASTIK (Determination of dissolved oxygen with polarographic oxygen sensor plastic membrane probe)

Plastic membrane sensor for polarographic oxygen measurement has been investigated. The Probe was constructed of: Pt as a working electrode; Ag- AgCl as a reference electrode and an auxiliary electrode; solution of KCl as an electrolyte solution; plastic wrap (thickness 72.7  m) as a membrane; and polyester polymer as a body of sensor. It was found that the polarographic oxygen sensor plastic membrane probe was suited for determination of dissolved oxygen with an optimum operating characteristics at applied voltage of –0.65 V and solution KCl 30% as an electrolyte. The probe showed that reduction current achieved steady state after 75 seconds. The standard calibration curve (concentration – current) showed that the linear relationships were achieved for dissolved oxygen in the range of 1.0 – 30.6 ppm. The analytical performance characteristics of the probe were: precision 0.87% – 30.0 %; calibration sensitivity 0.17 ppm/  A; analytical sensitivity 0.56 – 0.84 ppm/  A; and detection limit 0.8 ppm. The t- test and F-test at 95% confidence level showed that there was no significant difference between the determinations of dissolved oxygen by polarographic oxygen sensor membrane plastic and by Winkler method. Key words: membrane plastic, polarographic, steady state, Winkler method.

The Development of Micro Ball Supersonic Impact Test System

A micro ball supersonic impact test system was developed for the study of dynamic fracture of ceramic materials. This system consists of (1) low pressure gas gun, (2) sabot assembly and stopper block for velocity multiplication system, (3) velocity measurement device for sabot and ball, and (4) enclosed target box for final impact test. The principle of velocity multiplication system is similar to two stage gun. The plastic sabot assembly houses steel plunger and the void filled with silicone rubber. The sabot is stopped by the stopper block then the steel plunger inside the sabot compress the silicon rubber to high pressure to rupture the plastic membrane. Then the compressive energy of the silicon rubber is transferred to the ball. More than ten times of initial speed was attained. Non-contact velocity measurement system uses two set of ribbon laser with optical array sensor to measure the supersonic speed of the micro ball. Maximum speed up to 1200m/s for plastic and 600m/s for steel ball was attained. Perforation test of plastic film laminated glass window was successfully done by the developed impact system.