Applicability of winged bean extracts as organic corrosion inhibitors for reinforced steel in 0.5 ​M HCl electrolyte

Corrosion inhibition properties of winged bean (WB) extracts on reinforced steel in 0.5 ?M HCl solution was studied through experimental and theoretical calculation methods. The electrochemical studies suggested that inhibition efficiency increased with increasing concentration of WB extracts up to 95%. Nyquist diagrams revealed an increase in the charge transfer resistance values and a decrease in the constant phase element as the concentration of WB extracts were increased. The potentiodynamic polarization results revealed that WB extracts behave as mixed-type inhibitors, which physically adsorbed onto the reinforced steel surface. Effect of temperature study demonstrated that the corrosion resistance behaviour of WB extracts decreased with an increase in temperature, yielding a corrosion rate of 3.39 mmpy and 4.02 mmpy at 333 ?K with the incorporation of 1000 ?ppm WBW and WBE extracts, respectively. The thermodynamic study implied that the adsorption process follows the Langmuir isotherm with free energy adsorption of ΔG_ads WBW ?= ?-17.29 ?kJ ?mol^-1 and ΔG_ads WBE ?= ?-16.81 ?kJ ?mol^-1. Corresponding to the molecular modelling study, the semi-empirical method and molecular dynamics (MD) simulation investigated the correlation between the inhibitor compounds and the metal surface. One of the phenolic molecule constituents (gallic acid) was chosen to establish the structural and electronic parameters responsible for the high inhibition efficiency. A greater E_binding of 0.181 (a.u.) indicates that gallic acid in WB extracts can easily bind with the Fe surface, thus projecting a higher inhibitory performance. Surface morphology study affirmed the effective adsorption of WB extracts onto the surface of reinforced steel.     

Assembly of long carbon nanotube bridges across transparent electrodes using novel thickness-controlled dielectrophoresis

The assembly of carbon nanotubes (CNTs) across planner electrodes using dielectrophoresis (DEP) is one of the standard methods used to fabricate CNT-based devices such as sensors. The medium drag velocity caused by electrokinetic phenomena such as electrothermal and electroosmotic might drive CNTs away from the deposition area. This problem becomes critical at large-scale electrode structures due to the high attenuation of the DEP force. Herein, we simulated and experimentally validated a novel DEP setup that uses a top glass cover to minimize the medium drag velocity. The simulation results showed that the drag velocity can be reduced by 2–3 orders of magnitude compared with the basic DEP setup. The simulation also showed that the optimum channel height to result in a significant drag velocity reduction was between 100 μm and 240 μm. We experimentally report, for the first time, the assembly and alignment of CNT bridges across indium tin oxide (ITO) electrodes with spacing up to 125 μm. We also derived an equation to optimize the CNT's concentration in suspensions based on the electrode gap width and channel height. The deposition of long CNTs across ITO electrodes has potential use in transparent electronics and microfluidic systems.     

Potential of oil palm frond cellulose nanocrystals-activated carbon hydrogel beads for the removal of paracetamol from aqueous media

Cellulose - Water pollution via pharmaceutical drugs such as paracetamol has been a highly concerning issue, and effective measures must be taken to treat these aquatic contaminants. Hence, the...     

Reducing soiling issues on photovoltaic panels using hydrophobic self-cleaning coating

Journal of Sol-Gel Science and Technology - Surfaces that simultaneously exhibit hydrophobicity, high contact angle, and high transmission of visible light are of interest for many applications...     

Immune TB Antibody Phage Display Library as a Tool To Study B Cell Immunity in TB Infections

B cells and in particular antibodies has always played second fiddle to cellular immunity in regard to tuberculosis (TB). However, recent studies has helped position humoral immunity especially antibodies back into the foray in relation to TB immunity. Therefore, the ability to correlate the natural antibody responses of infected individuals toward TB antigens would help strengthen this concept. Phage display is an intriguing approach that can be utilized to study antibody-mediated responses against a particular infection via harvesting the B cell repertoire from infected individuals. The development of disease-specific antibody libraries or immune libraries is useful to better understand antibody-mediated immune responses against specific disease antigens. This study describes the generation of an immune single-chain variable fragment (scFv) library derived from TB-infected individuals. The immune library with an estimated diversity of 10⁹ independent clones was then applied for the identification of monoclonal antibodies against Mycobacterium tuberculosis α-crystalline as a model antigen. Biopanning of the library isolated three monoclonal antibodies with unique gene usage. This strengthens the role of antibodies in TB immunity in addition to the role played by cellular immunity. The developed library can be applied against other TB antigens and aid antibody-derived TB immunity studies in the future.