Properties of Self-Compacting Engineered Cementitious Composites containing Nano Silica Subjected to Elevated Temperatures

In this study, the properties of Engineered Cementitious Composites with the addition of Nano Silica is investigated when exposed to temperatures of up to 400C. 25 different mix proportions with PVA Fiber up to 2% and Nano Silica up to 4% is use to be molded into cubes of 50mmX50mmx50mm. These concrete cubes are water cured for 28 days before being heated up to temperatures of 100C, 200C, 300C and 400C. Then the residual strength, microstructure and pore characteristics will beinvestigated. Based on the compressive strength results of the concrete , the strength increases as the percentages of Nano Silica increases in the mix. The same also applies as the percentages of PVA Fiber increases. When subjected to elevated temperatures, the samples will show an increase of compressive strength to the temperature of 300C and then reduces at 400C. The morphology and microstructure of the samples are examined .All the ITZ between cement matrix and fiber are determined. The ITZ will decrease as the percentage of Nano Silica increases up to 3%. At 4%, the ITZ will increase marginally due to entrapped air in the fresh mixture thus causing more porosity. The MIP for the samples are done to determine the pore characteristics. The increase of Nano Silica will reduce the accessible porosity of the sample up to 3% addition of Nano Silica. Above that, the porosity of the composite will increase

A reduced risk of stroke with lithium exposure in bipolar disorder: a population‐based retrospective cohort study

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/115969/1/bdi12336.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/115969/2/bdi12336_am.pd

Thermogravimetric analysis of face mask waste: Kinetic analysis via iso-conversional methods

The surge of face mask waste in response to the global pandemic has proven to be a liability to the environment. Microfibers from plastic constituents of the face mask would cause microplastic pollution in the water bodies. Fortunately, these waste could be converted into renewable source of energy via thermochemical method, i.e. pyrolysis. However, the studies on the thermal decomposition of face masks and their kinetic mechanisms are not well-established. The aim of this paper focuses on the prospects of pyrolysis at low to high heating rates ranging from 10 °C min-1 to 100 °C min-1, to cater for the slow pyrolysis and fast pyrolysis modes. Following this, the thermal degradation behaviour of the face mask waste was studied via thermogravimetric analysis which determined the single peak temperature degradation range at 218 to 424 °C at 10 °C min-1, and maximum degradation rate was determined at 172.51 wt.% min-1 at 520 °C, with heating rate of 100 °C min-1. Flynn-Wall-Ozawa (FWO) and Starink method was employed to determine the average activation energy and average pre-exponential factor of the pyrolysis process of face mask waste. i.e., 41.31 kJ mol-1 and 0.9965, 10.43 kJ mol-1 and 0.9901 for FWO and Starink method, respectively

The echo-transponder electrode catheter: A new method for mapping the left ventricle

AbstractThe ability to locate catheter position in the left ventricle with respect to endocardial landmarks might enhance the accuracy of ventricular tachycardia mapping. An echotransponder system (Telectronics, Inc.) was compared with biplane fluoroscopy for left ventricular endocardial mapping. A 6F electrode catheter was modified with the addition of a piezoelectric crystal 5 mm from the tip. This crystal was connected to a transponder that received and transmitted ultrasound, resulting in a discrete artifact on the two-dimensional echocardiographic image corresponding to the position of the catheter tip.Catheters were introduced percutaneously into the left ventricle of nine anesthetized dogs. Two-dimensional echotransponder and biplane fluoroscopic images were recorded on videotape with the catheter at multiple endocardial sites. Catheter location was marked by delivering radiofrequency current to the distal electrode, creating a small endocardial lesion. Catheter location by echo-transponder and by fluoroscopy were compared with lesion location without knowledge of other data. Location by echo-transponder was 8.7 ± 5.1 mm from the center of the radiofrequency lesion versus 14 + 7.8 mm by fluoroscopy (n = 15, p = 0.023). Echo-transponder localization is more precise than is biplane fluoroscopy and may enhance the accuracy of left ventricular eledrophysiologic mapping

Highly Efficient Thermally Co-evaporated Perovskite Solar Cells and Mini-modules

The rapid improvement in the power conversion efficiency (PCE) of perovskite solar cells (PSCs) has prompted interest in bringing the technology toward commercialization. Capitalizing on existing industrial processes facilitates the transition from laboratory to production lines. In this work, we prove the scalability of thermally co-evaporated MAPbI3 layers in PSCs and mini-modules. With a combined strategy of active layer engineering, interfacial optimization, surface treatments, and light management, we demonstrate PSCs (0.16 cm2 active area) and mini-modules (21 cm2 active area) achieving record PCEs of 20.28% and 18.13%, respectively. Un-encapsulated PSCs retained ∼90% of their initial PCE under continuous illumination at 1 sun, without sample cooling, for more than 100 h. Looking toward tandem and building integrated photovoltaic applications, we have demonstrated semi-transparent mini-modules and colored PSCs with consistent PCEs of ∼16% for a set of visible colors. Our work demonstrates the compatibility of perovskite technology with industrial processes and its potential for next-generation photovoltaics

New Measure of Insulin Sensitivity Predicts Cardiovascular Disease Better than HOMA Estimated Insulin Resistance

10.1371/journal.pone.0074410PLoS ONE89-POLN