Minor-phase composition changes in 12CrMoVNb steels during long-term exposure

2003 ◽  
Vol 81 (2-3) ◽  
pp. 480-482 ◽  
Author(s):  
V Vodarek ◽  
A Strang
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.


1992 ◽  
Vol 154 (2) ◽  
pp. 197-205 ◽  
Author(s):  
X. Du ◽  
J.A. Whiteman ◽  
R.C. Thomson ◽  
H.K.D.H. Bhadeshia
Keyword(s):  

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.


2019 ◽  
Vol 150 ◽  
pp. 166-173
Author(s):  
Sergey Yu. Kondrat'ev ◽  
Grigoriy P. Anastasiadi ◽  
Alina V. Ptashnik ◽  
Sergey N. Petrov

Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4268
Author(s):  
Věra Vodičková ◽  
Martin Švec ◽  
Pavel Hanus ◽  
Pavel Novák ◽  
Antonín Záděra ◽  
...  

The effect of phase composition and morphology on high-temperature strength in the compression of Fe-Al-Si-based iron aluminides manufactured by casting was investigated. The structure and high-temperature strength in the compression of three alloys—Fe28Al5Si, Fe28Al5Si2Mo, and Fe28Al5Si2Ti—were studied. Long-term (at 800 °C for 100 h) annealing was performed for the achievement of structural stability. The phase composition and grain size of alloys were primarily described by means of scanning electron microscopy equipped with energy dispersive analysis and Electron Backscatter Diffraction (EBSD). The phase composition was verified by X-ray diffraction (XRD) analysis. The effect of Mo and Ti addition as well as the effect of long-term annealing on high-temperature yield stress in compression were investigated. Both additives—Mo and Ti—affected the yield stress values positively. Long-term annealing of Fe28Al5Si-X iron aluminide alloyed with Mo and Ti deteriorates yield stress values slightly due to grain coarsening.


2013 ◽  
Vol 592-593 ◽  
pp. 477-480
Author(s):  
Andrzej Nowotnik ◽  
Jan Sieniawski ◽  
Marcin Zawadzki ◽  
Marek Góral

The paper presents the influence of long-term heat treatment on aluminide coating. The MAR M-200 nickel superalloy was use as base material. The aluminide coating was deposited in low-activity chemical vapour deposition process using Ion Bond BPX Pro 325s device with following parameters: temperature 1040°C, time 12 hours, pressure 150 mbar. The samples (14 mm diameter) were annealed at 1020°C in vacuum for 12, 16 and 20 hours respectively. The XRD phase analysis and SEM microstructural observation with EDS analysis were conducted. The phase composition analysis showed that after deposition the NiAl phase is a main component of the coating. After the 20-hour-long annealing presence of Ni3Al phase in the coating was observed. Changes in structure of coatings and Al content during heat treatment were detected as well. The maximum duration of heat treatment performed for Ni superalloy with aluminide coating without significant changes in coating phase composition and microstructure is 16 hours.


1996 ◽  
Vol 35 (5) ◽  
pp. 597-601 ◽  
Author(s):  
D.-K. Na ◽  
J.B. Cohen ◽  
P.W. Voorhees

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

Author(s):  
Ulla Simon ◽  
Manuel Harth ◽  
Sebastian Arndt ◽  
Almuth Berthold ◽  
Oliver Görke ◽  
...  

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