Modelling the carbide composition changes in CrMoV steel during long-term tempering

1992 ◽  
Vol 154 (2) ◽  
pp. 197-205 ◽  
Author(s):  
X. Du ◽  
J.A. Whiteman ◽  
R.C. Thomson ◽  
H.K.D.H. Bhadeshia
Keyword(s):  
2020 ◽  
Vol 22 (1) ◽  
pp. 221
Author(s):  
Joanna Wójtowicz ◽  
Adam K. Jagielski ◽  
Agnieszka Mostowska ◽  
Katarzyna B. Gieczewska

The origin of chlorophyll b deficiency is a mutation (ch1) in chlorophyllide a oxygenase (CAO), the enzyme responsible for Chl b synthesis. Regulation of Chl b synthesis is essential for understanding the mechanism of plant acclimation to various conditions. Therefore, the main aim of this study was to find the strategy in plants for compensation of low chlorophyll content by characterizing and comparing the performance and spectral properties of the photosynthetic apparatus related to the lipid and protein composition in four selected Arabidopsis ch1 mutants and two Arabidopsis ecotypes. Mutation in different loci of the CAO gene, viz., NW41, ch1.1, ch1.2 and ch1.3, manifested itself in a distinct chlorina phenotype, pigment and photosynthetic protein composition. Changes in the CAO mRNA levels and chlorophyllide a (Chlide a) content in ecotypes and ch1 mutants indicated their significant role in the adjustment mechanism of the photosynthetic apparatus to low-light conditions. Exposure of mutants with a lower chlorophyll b content to short-term (1LL) and long-term low-light stress (10LL) enabled showing a shift in the structure of the PSI and PSII complexes via spectral analysis and the thylakoid composition studies. We demonstrated that both ecotypes, Col-1 and Ler-0, reacted to high-light (HL) conditions in a way remarkably resembling the response of ch1 mutants to normal (NL) conditions. We also presented possible ways of regulating the conversion of chlorophyll a to b depending on the type of light stress conditions.


Author(s):  
Boštjan Jakše ◽  
Barbara Jakše ◽  
Stanislav Pinter ◽  
Jernej Pajek ◽  
Nataša Fidler Mis

Failure of various weight-loss programs and long-term maintenance of favorable body composition in all kinds of people is high, since the majority go back to old dietary patterns. Many studies have documented the efficacy of a plant-based diet (PBD) for body mass management, but there are opinions that maintaining a PBD is difficult. We aimed to evaluate the long-term success of a whole-food plant-based (WFPB) lifestyle program. We investigated the differences in the obesity indices and lifestyle of 151 adults (39.6 ± SD 12.5 years), who were on our program for short (0.5–<2 years), medium (2–<5 years), or long term (5–10 years). Body-composition changes were favourable for all three groups, both genders and all participants. There were no differences in relative body-composition changes (BMI, body fat percentage and muscle mass index (MMI)) between the three groups. All participants improved their BMI (baseline mean pre-obesity BMI range (kg/m2): 26.4 ± 5.6 to normal 23.9 ± 3.8, p < 0.001), decreased body mass (–7.1 ± 8.3 kg, p < 0.001) and body fat percentage (–6.4 ± 5.6 % points, p < 0.001). 85.6% (101 out of 118) of parents of underage children (< 18 years), introduced WFPB lifestyle to their children. Those with the highest BMI at baseline lost the most of: a) BMI units, b) total body mass and c) body fat (a) (kg/m2) (–5.6 ± SD 2.9, –2.4 ± 1.8 and –0.9 ± 1.5), b) (kg) (–16.1 ± SD 8.8, –7.1 ± 5.4 and –2.5 ± 4.5) and c) (% points) (–9.5 ± SD 5.7, –6.6 ± 4.6 and –4.7 ± 5.3) for participants who had baseline BMI in obese, overweight and normal range, respectively; pbaseline vs. current < 0.001 for all). WFPB lifestyle program provides long-term lifestyle changes for reversal of obesity and is effective transferred to the next generation.


2019 ◽  
Author(s):  
Ye Tao ◽  
Jennifer G. Murphy

Abstract. Aerosol pH is difficult to measure directly but can be calculated if the chemical composition is known with sufficient accuracy and precision to calculate the aerosol water content and the H+ concentration through ion balance. In practical terms, simultaneous measurements of at least one semi-volatile constitute, e.g. NH3 or HNO3, are required to provide a constraint on the calculation of pH. Long-term records of aerosol pH are scarce due to the limited monitoring of NH3 in conjunction with PM2.5. In this study, 10-year (2007–2016) records of pH of PM2.5 at six eastern Canadian sites were calculated using the E-AIM II model with the input of gaseous NH3, gaseous HNO3 and major water-soluble inorganic ions in PM2.5 provided by Canada's National Air Pollution Surveillance (NAPS) Program. Clear seasonal cycles of aerosol pH were found with lower pH (~2) in summer and higher pH (~3) in winter consistently across all six sites, while the day-to-day variations of aerosol pH were higher in winter compared to summer. Tests of the sensitivity of aerosol pH to meteorological parameters demonstrate that the changes in ambient temperature largely drive the seasonal cycle of aerosol pH. The sensitivity of pH to chemical composition shows that pH has different responses to the changes in chemical composition in different seasons. During summertime, aerosol pH was mainly determined by temperature with limited impact from changes in NHx or sulfate concentrations. However, in wintertime, both meteorological parameters and chemical composition contribute to the variations in aerosol pH, resulting in the larger variation during wintertime. This study reveals that the sensitivity of aerosol pH to chemical composition is distinctly different under different meteorological conditions and needs to be carefully examined for any particular region.


2010 ◽  
Vol 5 (2) ◽  
pp. 150
Author(s):  
F. Joly ◽  
E. Essmaeel ◽  
A. Ostertag ◽  
C. Clerici ◽  
A. Boulier ◽  
...  

2017 ◽  
Vol 82 (3) ◽  
pp. 594-604 ◽  
Author(s):  
Chao-Hui Feng ◽  
Cheng Li ◽  
Juan Francisco García-Martín ◽  
Pradeep Kumar Malakar ◽  
Yue Yan ◽  
...  

2021 ◽  
Vol 1 (4) ◽  
pp. 1-25
Author(s):  
V.V. Ershov ◽  

The article provides an overview of Russian and foreign studies on assessment of the composition of atmospheric fallout and soil waters in forest ecosystems. The conclusion was made that little attention is given to the transformation of precipitation chemical composition by forest ecosystems, taking into account the influence of the species composition of the stand and the mosaic structure of the biogeocenosis (areas below the crowns, between the crowns, and open sites). European studies usually look at long-term development of the composition of atmospheric fallout and lysimetric waters, detecting long-term trends in composition changes of atmospheric and soil waters and identifying the factors driving these changes. In Russia, no such long-term (lasting for more than 10 years) continuous observations on the effect of man-made pollution on the composition and properties of atmospheric and soil waters were carried out. This task is very relevant for Russia and, especially, for its industrial regions.


2021 ◽  
Author(s):  
Noemie Taquet ◽  
Wolfgang Stremme ◽  
Claudia Rivera ◽  
Alejandro Bezanilla ◽  
Michel Grutter ◽  
...  

<p>Changes in the eruptive dynamics are mainly controlled by the magma gas content, and the degassing processes impacting the magma viscosity and ascending speed. The progressive exsolution of the gas species, their release at different depths, their mutual interaction and the eventual assimilation of crustal rocks are reflected in the volcanic plume composition changes. Combining long-term ground-based FTIR and UV remote measurements of the Popocatepetl's plume, seismic data and visual monitoring, we explore the relationship between the gas composition changes in the volcanic plume and the transition between extrusive and passive degassing regimes.</p><p>SO2, HCl, HF, BrO, SiF4 and CO2 are simultaneously measured in the volcanic plume since 2013 from the Altzomoni observatory, located 12 km north of the crater. We capture several phases of lava dome growth, different types of explosions and passive degassing periods. The evolution of the gas species ratios through these events allows deciphering the degassing processes.</p>


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