Ratiometric method for ozone absorption cross section measurement

Ultraviolet absorption spectroscopy has been practised for ozone concentration measurement because the method of measurement is fast and reliable. Ratiometric method corrects intensity drift of light source for improvement of measurement stability. However, ozone absorption cross section may not be determined via ratiometric method because of limitation of existing Beer–Lambert law. Absorption cross section defines strength of absorption, which is an important parameter for calculation of ozone concentration. Firstly, optical path length of gas cell that suits dynamic range of ozone monitor in this work (less than 1000 ppm) is determined. Based on spectralcalc.com simulation, gas cells of optical path lengths of 5 cm, 10 cm and 20 cm are optimized for concentration measurement from 494.1 ppm to 988.1 ppm, 247.0 ppm to 494.1 ppm and 123.5 ppm to 247.0 ppm respectively. Secondly, Beer–Lambert law deviation is observed when long gas cell of optical path length 10 cm is used to measure high ozone concentration from 357 ppm to 971 ppm. Typically, ozone is sampled using strong absorption wavelength for high sensitivity measurement. When strong absorption wavelengths cause saturation, linearity of measurement is preserved by sampling ozone using weak absorption wavelength 279.95 nm. Thirdly, temperature and pressure stability of ozone absorption cross section are verified using spectralcalc.com simulation. Finally, a novel equation is established based on Beer– Lambert law for measurement of ozone absorption cross section via ratiometric method. The equation is verified for ozone concentration measurement from 450 ppm to 989 ppm using short gas cell of optical path length 5 cm, sampling wavelength 260.99 nm and reference wavelength 377.05 nm. The equation is attractive to researchers in areas of absorption spectroscopy and optical gas sensor because ratiometric method is gaining popularity for high stability ozone concentration measurement

Fundamental Review to Ozone Gas Sensing Using Optical Fibre Sensors

The manuscript is a review of basic essentials to ozone gas sensing with optical methods. Optical methods are employed to monitor optical absorption, emission, reflectance and scattering of gas samples at specific wavelengths of light spectrum. In the light of their importance in numerous disciplines in analytical sciences, necessary integral information that serves both as a basis and reference material for intending researchers and others in the field is inevitable. This review provides insight into necessary essentials to gas sensing with optical fibre sensors. Ozone gas is chosen as a reference gas. Simulation results for ozone gas absorption cross section in the ultraviolet (UV) region of the spectrum using spectralcalc.com simulation have also been included

Varying Effects of Temperature and Path-length on Ozone Absorption Cross-Section

Inconsistencies in the absorption cross section of ozone have been observed. Hence, for accurate measurement, we have reported the combined effects of varying optical path-length and temperature on the ozone gas absorption cross section (OACS) at 334.15nm. Adopting optical absorption spectroscopy, results of the (OACS) have been simulated using spectralcalc simulator with HITRAN 12 has the latest line list. OACS increased by 52.27% as the temperature increased from 100K to 350K while it was slightly affected by a 0.007% decrease varying the path-length from 0.75cm-130cm

Stylometric Analysis of Chinese Buddhist texts - Do different Chinese translations of the Gaṇḍavyūha reflect stylistic features that are typical for their age?

Below we develop a method to determine whether the use of grammatical particles in Chinese Buddhist scriptures is characteristic for the period of their translation. The corpus consists of three different Chinese translations of an early Indian Mahāyāna text from two different periods. We use the results of Principal Component Analysis (PCA) to discern if the samples of texts from different periods cluster together. We found that PCA used on common grammatical particles that exhibit great variance between texts, but occur evenly distributed within the texts, does in this case indeed yield distinctive patterns that distinguish the translations from different time periods. This is relevant for historical Chinese linguistics and Buddhist studies. It allows us to identify grammatical particles the use of which differs between translations from different periods. This in turn is an important basis for further research into Buddhist Hybrid Chinese translation idioms and the better attribution and dating of Chinese Buddhist texts

Varying effects of temperature and path-length on ozone absorption cross-section

Inconsistencies in the absorption cross section of ozone have been observed. Hence, for accurate measurement, we have reported the combined effects of varying optical path-length and temperature on the ozone gas absorption cross section (OACS) at 334.15nm. Adopting optical absorption spectroscopy, results of the (OACS) have been simulated using spectralcalc simulator with HITRAN 12 has the latest line list. OACS increased by 52.27% as the temperature increased from 100K to 350K while it was slightly affected by a 0.007% decrease varying the path-length from 0.75cm-130cm

Unraveling the Effect of Rh Isolation on Shallow d States of Gallium–Rhodium Alloys

In this study, we report the electronic and chemical structure of supported GaRh alloys as model systems for the active phase in supported catalytically active liquid metal solutions (SCALMS). We prepared a series of gallium–rhodium samples with different Rh contents and tracked the evolution of the sample topography and surface electronic structure via photoemission spectroscopy in combination with ab initio calculations and electron microscopy. Our results reveal a characteristic shift of the Rh 3d core levels and narrowing and shifting of the Rh 4d derived band with decreasing Rh content. Calculations show that these spectroscopic observations can be explained by the coexistence of isolated Rh atoms in random GaRh alloys and GaRh intermetallic compounds (IMCs). These results contribute to an enhancement of the fundamental understanding of the electronic surface structure of GaRh alloys, which is crucially required for apprehending and thus further exploiting the improved catalytic activity of GaRh SCALMS

Investigation of the effect of inlet radius on the response time of a transmission type ozone sensor

The effect of inlet radius of a transmission type optical gas cell on its response time is reported. Six gas cells of varying lengths, and internal radius of 0.32cm were considered at first and then other internal diameters were also investigated afterwards. The effect of inlet radius is easily discernible at all velocities considered; however it is more pronounced at lower flow rates. At a velocity of 16.79cm/s of ozone gas, and for a target sensing time of ≤ 0.5 seconds; we observed that the inlet radius requirements for gas cells of varying lengths and varying internal diameters is not the same for a specific target sensing speed. The length and the internal radius of a gas cell are proportional to its inlet radiu

Wide range analysis of absorption spectroscopy ozone gas sensor

A wide range analysis of spectroscopic ozone gas sensor is conducted in order to obtain specific affected wavelength when 616 ppm to 999 ppm of ozone concentration is released into 5 cm gas cell of transmission type. It is observed that by employing different wavelength in ultraviolet region based on spectroscopic ozone detection, obvious differences of transmittance value are obtained for each particular wavelength. Consideration with Twyman-Lothian equation, specific wavelength at 239 nm, 240 nm, 241 nm, 242 nm, 278 nm, 279 nm, 280 nm, 281 nm is proven to achieve wide range of ozone detection when low relative error of concentration is achieved by value of transmittance in range between 0.25 and 0.5

Risk of cardiovascular events and death associated with initiation of SGLT2 inhibitors compared with DPP-4 inhibitors:an analysis from the CVD-REAL 2 multinational cohort study

Background Cardiovascular outcome trials have shown cardiovascular benefit with sodium-glucose co-transporter-2 (SGLT2) inhibitors in patients with type 2 diabetes, whereas dipeptidyl peptidase-4 (DPP-4) inhibitors have not shown an effect. We aimed to address knowledge gaps regarding the comparative effectiveness of SGLT2 inhibitor use in clinical practice (with DPP-4 inhibitor use as an active comparator) across a range of cardiovascular risks and in diverse geographical settings. Methods In this comparative cohort study, we used data from clinical practice from 13 countries in the Asia-Pacific, Middle East, European, and North American regions to assess the risk of cardiovascular events and death in adult patients with type 2 diabetes newly initiated on SGLT2 inhibitors compared with those newly initiated on DPP-4 inhibitors. De-identified health records were used to select patients who were initiated on these drug classes between Dec 1, 2012, and May 1, 2016, with follow-up until Dec 31, 2014, to Nov 30, 2017 (full range; dates varied by country). Non-parsimonious propensity scores for SGLT2 inhibitor initiation were developed for each country and patients who were initiated on an SGLT2 inhibitor were matched with those who were initiated on a DPP-4 inhibitor in a 1:1 ratio. Outcomes assessed were hospitalisation for heart failure, all-cause death, myocardial infarction, and stroke. Hazard ratios (HRs) were estimated by country and then pooled in a weighted meta-analysis. Findings Following propensity score matching, 193 124 new users of SGLT2 inhibitors and 193 124 new users of DPP-4 inhibitors were included in the study population. Participants had a mean age of 58 years (SD 12.2), 170 335 (44.1%) of 386 248 were women, and 111933 (30.1%) of 372 262 had established cardiovascular disease. Initiation of an SGLT2 inhibitor versus a DPP-4 inhibitor was associated with substantially lower risks of hospitalisation for heart failure (HR 0.69, 95% CI 0. 61-0. 77; p Interpretation In this large, international, observational study, initiation of SGLT2 inhibitors versus DPP-4 inhibitors was associated with lower risks of heart failure, death, myocardial infarction, and stroke, providing further support for the cardiovascular benefits associated with use of SGLT2 inhibitors in patients with type 2 diabetes. Copyright (C) 2020 Elsevier Ltd. All rights reserved

Contesting the Dominant Discourse of Child Sexual Abuse: Sexual Subjects, Agency, and Ethics

Responding to previous scholars’ call to explore the complexities of child sexual abuse (CSA), this article presents narratives of CSA and scrutinizes a binary construction underpinning this discourse of CSA, namely, the positioning of children as powerless and adults as powerful. The narratives belong to three Indonesian young people who have had sexual interactions with adults when they were children. The findings demonstrate how this binary positioning has been both drawn upon and resisted in the ways participants understand their sexual experiences. This article contributes to the existing literature by providing analyses of some vignettes of everyday experiences of how children might be constituted as sexual subjects, including their capability to exercise agency, perform resistance, and negotiate ethics. The implications of the findings are discussed in relation to how the recognition of children as sexual subjects and their sexual agency might be beneficial for parents, educators, and counselors