Effects of Applying Different Resonance Amplitude on the Performance of the Impedance-Based Health Monitoring Technique Subjected to Damage.

Smart materials such as piezoelectric transducers can be used for monitoring the health of building structures. In this study, a structural health monitoring technique known as the electromechanical impedance (EMI) method is investigated. Although the EMI method has the advantage of using a single piezoelectric patch that acts both as the actuator and as the sensor, there are still many issues to be addressed. To further understand the problem, the performance of the EMI method on a structure subjected to progressive damage at different resonance frequency ranges and peak amplitudes was investigated using three different statistical metrics: root-mean-square deviation (RMSD), mean absolute percentage deviation (MAPD) and correlation coefficient deviation (CCD). Metal plates were used throughout the study. The results acquired could be used to further understand the damage identification performance of the EMI method.

A synthetic study and characterization of the Pt(II) complexes with bipyridines back-born system.

The reaction of platinum [Pt(5,5-dmbpy)]Cl2 (5,5-dmbpy = 5,5'-dimethyl-2,2'-bipyridine) with 4,4'-dimethyl-2,2'-bipyridine (4,4-dmbpy), [Pt(dbbpy)]Cl2 (dbbpy = 4,4'-dibutyl-2,2'-bipyridine), [Pt(dpbpy)]Cl2 (dpbpy = 4,4'-dipentyl-2,2'-bipyridine) with 5,5'-dimethyl-2,2'-bipyridine (5,5-dmbpy) affords the following complexes: [(4,4-dmbpy)Pt(5,5-dmbpy)][PF6]2 (1) and [(dbbpy)Pt(5,5-dmbpy)][PF6]2 (2), [(dpbpy)Pt(5,5-dmbpy)][PF6]2 (3), [(5,5-dmbpy)Pt(5,5-dmbpy)][PF6]2 (4). This study was synthesized new platinum complex compounds utilizing ligand of 5,5'-Dimethyl-2,2'-dipyridyl System. To study the chemical composition was used 1H(13C)-NMR, UV-vis, Spectro photometer and Measurements about optical physics and chemical properties were measured to use spectrofluorometer. UV-vis absorption area was measured 310 nm to 383 nm and luminous wavelength was measured 390 nm to 419 nm.

Analysis of extracellular polymeric substance (EPS) release in anaerobic sludge holding tank and its effects on membrane fouling in a membrane bioreactor (MBR).

Amongst sludge reduction strategies, the anaerobic side-stream sludge holding tank (SHT) is of particular interest because it has shown significant sludge reduction efficiency. However, due to the anaerobic and starving environment of the SHT, the release of extracellular polymeric substance (EPS) may be stimulated, and it may hamper the application of the SHT to the membrane bioreactor. In order to investigate the effect of sludge storage on EPS release, sludge samples from a pilot-scale sequencing batch reactor coupled with SHT was incubated in a series of bench-scale SHT reactors for different periods of time (0-24 h). The increase in EPS was not significant until 12 h of incubation (9.3%), while 40.9% of the increase was observed in the sample incubated for 24 h. The rapid increase in EPS concentration after 12 h indicates a greater rate of cell lysis than that with EPS consumption as substrate. Since inducing the initial stage of the endogenous phase within microorganisms is a key factor for the successful operation of the SHT for sludge reduction, the retention time for the SHT should be shorter than the time for the sudden increase in EPS release.

Recent Application of Nanomaterials to Overcome Technological Challenges of Microbial Electrolysis Cells.

Microbial electrolysis cells (MECs) have attracted significant interest as sustainable green hydrogen production devices because they utilize the environmentally friendly biocatalytic oxidation of organic wastes and electrochemical proton reduction with the support of relatively lower external power compared to that used by water electrolysis. However, the commercialization of MEC technology has stagnated owing to several critical technological challenges. Recently, many attempts have been made to utilize nanomaterials in MECs owing to the unique physicochemical properties of nanomaterials originating from their extremely small size (at least <100 nm in one dimension). The extraordinary properties of nanomaterials have provided great clues to overcome the technological hurdles in MECs. Nanomaterials are believed to play a crucial role in the commercialization of MECs. Thus, understanding the technological challenges of MECs, the characteristics of nanomaterials, and the employment of nanomaterials in MECs could be helpful in realizing commercial MEC technologies. Herein, the critical challenges that need to be addressed for MECs are highlighted, and then previous studies that used nanomaterials to overcome the technological difficulties of MECs are reviewed.

Comparison of green tea extract and epigallocatechin gallate on blood pressure and contractile responses of vascular smooth muscle of rats.

The present study was conducted to investigate the effects of green tea extract (GTE) on arteral blood pressure and contractile responses of isolated aortic strips of the normotensive rats and to establish the mechanism of action. The phenylephrine (10(-8) approximately 10(-5) M)-induced contractile responses were greatly inhibited in the presence of GTE (0.3 approximately 1.2 mg/mL) in a dose-dependent fashion. Also, high potassium (3.5 x 10(-2) approximately 5.6 x 10(-2) M)-induced contractile responses were depressed in the presence of 0.6 approximately 1.2 mg/mL of GTE, but not affected in low concentration of GTE (0.3 mg/mL). However, epigallocatechin gallate (EGCG, 4 approximately 12 microg/mL) did not affect the contractile responses evoked by phenylephrine and high K+. GTE (5 approximately 20 mg/kg) given into a femoral vein of the normotensive rat produced a dose-dependent depressor response, which is transient. Interestingly, the infusion of a moderate dose of GTE (10 mg/kg/30 min) made a significant reduction in pressor responses induced by intravenous norepinephrine. However, EGCG (1 mg/kg/30 min) did not affect them. Collectively, these results obtained from the present study demonstrate that intravenous GTE causes a dose-dependent depressor action in the anesthetized rat at least partly through the blockade of adrenergic alpha1-receptors. GTE also causes the relaxation in the isolated aortic strips of the rat via the blockade of adrenergic alpha1-receptors, in addition to the unknown direct mechanism. It seems that there is a big difference in the vascular effect between GTE and EGCG.