Thermal Stability of Moniliformin at Varying Temperature, pH, and Time in an Aqueous Environment†

Moniliformin (MON) is a widely occurring mycotoxin, produced mainly by Fusarium proliferatum and Fusarium subglutinans in corn, that has been shown to be acutely toxic for various animal species and is a suspected cause of Keshan disease in China. The effects of temperature (100, 125, and 150°C) and pH (4, 7, and 9) on the stability of MON were determined in aqueous buffer solutions at processing times ranging from 10 to 60 min. The percentage of MON reduction was positively related to increasing temperature and pH. MON was most stable at pH 4. After 60 min at pH 4 and 150°C, MON was reduced by only 5%. Heating at pH 10 caused major reduction of MON. After 60 min at pH 10 and 100, 125, and 150°C, MON was reduced by 56, 72, and 83%, respectively. One trial done at 175°C and pH 10 showed that less than 1% MON remained after 60 min of processing.

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The Effects of Temperature and of Egg-Laying on the Longevity of Drosophila subobscura

Science of Aging Knowledge Environment ◽

10.1126/sageke.2002.37.cp15 ◽

2002 ◽

Vol 2002 (37) ◽

Author(s):

J. Maynard Smith

Keyword(s):

Animal Species ◽

Initial Period ◽

Egg Laying ◽

Drosophila Subobscura ◽

Force Of Mortality ◽

Different Temperatures ◽

Effects Of Temperature ◽

Favourable Environment ◽

Rate Of Ageing ◽

Increasing Temperature

If an outbred population of adult Drosophila is kept from the time of emergence in a uniform and favourable environment there is a fairly protracted initial period during which very few individuals die, followed by a period during which the force of mortality rises rapidly until all individuals are dead. Similar life tables can be obtained for most animal species, provided that the environment is favourable and the population is neither genetically very diverse nor excessively inbred. Such results show that progressive changes take place in individuals, starting at the time of emergence, and that these changes ultimately result in death or render individuals increasingly susceptible to various extrinsic causes of death. As would be expected, in poikilotherms such changes proceed more rapidly at higher temperatures, as is shown by the decrease in the expectation of life with increasing temperature. It was the purpose of the present investigation to discover how far the processes responsible for death in D. subobscura are the same at different temperatures, differing only in the rate at which they proceed, and how far different processes are concerned at different temperatures. The results obtained strongly suggest that different processes are responsible for ageing at different temperatures; they also indicate a connexion between the rate of egg-laying and the rate of ageing, and this possibility has been confirmed by a study of ageing in virgin females and in females lacking ovaries. Reproduced by permission. J. Maynard Smith, The Effects of Temperature and of Egg-Laying on the Longevity of Drosophila subobscura. J. Exp. Biol. 35 , 832-842 (1958).

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Thermal Stability of CsPbBr3 Perovskite Quantum Dots Assembled with SBA-15

Coatings ◽

10.3390/coatings11080953 ◽

2021 ◽

Vol 11 (8) ◽

pp. 953

Author(s):

Hongyu Chen ◽

Yunfei Wang ◽

Jianing Wang ◽

Wenyan Liu

Keyword(s):

Thermal Stability ◽

Quantum Dots ◽

Red Shift ◽

Heating And Cooling ◽

Metal Halide Perovskite ◽

Perovskite Quantum Dots ◽

Pl Intensity ◽

The Stability ◽

Increasing Temperature ◽

Thermal Stability Of

Nowadays, the excellent performance of metal halide perovskite quantum dots (PQDs) has been demonstrated, but the stability is still a perplexing issue. In this paper, the CsPbBr3 QDs were assembled into SBA-15 for the first time. The thermal stability and photoluminescence (PL) intensity of SBA-15@CsPbBr3 QDs were improved. The PL spectra of pure CsPbBr3 QDs have red-shift (~6 nm) with the increasing temperature. However, that of SBA-15@CsPbBr3 QDs have almost no red-shift. The PL intensity of SBA-15@CsPbBr3 QDs decreased slightly after heating and cooling for several times. By comparison, the PL intensity of pure CsPbBr3 QDs decreased more significantly. The experimental results showed that SBA-15 played a significant role in improving the thermal stability of PQDs, which will have an excellent potential for the application of PQDs in the future.

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Investigation of the effects of temperature and ions on the interaction between ECG and BSA by the fluorescence quenching method

Archives of Biological Sciences ◽

10.2298/abs1102325z ◽

2011 ◽

Vol 63 (2) ◽

pp. 325-331 ◽

Cited By ~ 13

Author(s):

Jinyao Zhao ◽

Xinyu Jiang ◽

Xin Liu ◽

Fenglian Ren

Keyword(s):

Bovine Serum Albumin ◽

Binding Sites ◽

Binding Constants ◽

Epicatechin Gallate ◽

Number Of Binding Sites ◽

Fluorescence Quenching Method ◽

Effects Of Temperature ◽

Quenching Method ◽

The Stability ◽

Increasing Temperature

The effects of temperature and common ions on binding (-)-epicatechin gallate (ECG) to bovine serum albumin (BSA) are investigated. The binding constants (Ka) between ECG and BSA are 1.20 ? 106 (17?C), 1.38 ? 106 (27?C), and 5.69 x 106 L mol-1 (37?C), and the number of binding sites (n) were 1.14, 1.15, and 1.26, respectively. These results showed that the increasing temperature improves the stability of the ECG-BSA system, which results in a higher binding constant and the number of binding sites of the ECG-BSA system. The presence of Co2+ and Zn2+ ions decreased the binding constants (Ka) and the number of binding sites (n) of ECG-BSA complex. However, the presence of Cu2+ and Ni2+ increased the affinity of ECG for BSA largely. The positive ?H and positive ?S indicated that hydrophobic forces might play a major role in the binding between ECG and BSA.

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Complexes of Copper and Iron with Pyridoxamine, Ascorbic Acid, and a Model Amadori Compound: Exploring Pyridoxamine’s Secondary Antioxidant Activity

Antioxidants ◽

10.3390/antiox10020208 ◽

2021 ◽

Vol 10 (2) ◽

pp. 208

Author(s):

Guillermo García-Díez ◽

Roger Monreal-Corona ◽

Nelaine Mora-Diez

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Rate Constant ◽

Stable Complex ◽

Aqueous Environment ◽

Oh Radicals ◽

Bidentate Ligands ◽

Superoxide Radical Anion ◽

Amadori Compound ◽

The Stability

The thermodynamic stability of 11 complexes of Cu(II) and 26 complexes of Fe(III) is studied, comprising the ligands pyridoxamine (PM), ascorbic acid (ASC), and a model Amadori compound (AMD). In addition, the secondary antioxidant activity of PM is analyzed when chelating both Cu(II) and Fe(III), relative to the rate constant of the first step of the Haber-Weiss cycle, in the presence of the superoxide radical anion (O2•−) or ascorbate (ASC−). Calculations are performed at the M05(SMD)/6-311+G(d,p) level of theory. The aqueous environment is modeled by making use of the SMD solvation method in all calculations. This level of theory accurately reproduces the experimental data available. When put in perspective with the stability of various complexes of aminoguanidine (AG) (which we have previously studied), the following stability trends can be found for the Cu(II) and Fe(III) complexes, respectively: ASC < AG < AMD < PM and AG < ASC < AMD < PM. The most stable complex of Cu(II) with PM (with two bidentate ligands) presents a ΔGf0 value of −35.8 kcal/mol, whereas the Fe(III) complex with the highest stability (with three bidentate ligands) possesses a ΔGf0 of −58.9 kcal/mol. These complexes can significantly reduce the rate constant of the first step of the Haber-Weiss cycle with both O2•− and ASC−. In the case of the copper-containing reaction, the rates are reduced up to 9.70 × 103 and 4.09 × 1013 times, respectively. With iron, the rates become 1.78 × 103 and 4.45 × 1015 times smaller, respectively. Thus, PM presents significant secondary antioxidant activity since it is able to inhibit the production of ·OH radicals. This work concludes a series of studies on secondary antioxidant activity and allows potentially new glycation inhibitors to be investigated and compared relative to both PM and AG.

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Polydomain Structure of Epitaxial PbTiO3 films on MgO

MRS Proceedings ◽

10.1557/proc-493-111 ◽

1997 ◽

Vol 493 ◽

Cited By ~ 1

Author(s):

S. P. Alpay ◽

A. S. Prakash ◽

S. Aggarwal ◽

R. Ramesh ◽

A. L. Roytburd ◽

...

Keyword(s):

Domain Structure ◽

Pulsed Laser ◽

Laser Deposition ◽

X Ray Diffraction ◽

X Ray ◽

Theoretical Predictions ◽

The Stability ◽

Increasing Temperature ◽

Stable Domains ◽

Domain Stability

ABSTRACTA PbTiO3(001) film grown on MgO(001) by pulsed laser deposition is examined as an example to demonstrate the applications of the domain stability map for epitaxial perovskite films which shows regions of stable domains and fractions of domains in a polydomain structure. X-ray diffraction studies indicate that the film has a …c/a/c/a… domain structure in a temperature range of °C to 400°C with the fraction of c-domains decreasing with increasing temperature. These experimental results are in excellent agreement with theoretical predictions based on the stability map.

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Intrinsic Thermal Stability of Anisotropic Thin-Film Superconductors

Journal of Heat Transfer ◽

10.1115/1.2910330 ◽

1990 ◽

Vol 112 (1) ◽

pp. 10-15 ◽

Cited By ~ 21

Author(s):

M. I. Flik ◽

C. L. Tien

Keyword(s):

Thin Film ◽

Thermal Stability ◽

Stability Criterion ◽

High Temperature Superconductors ◽

Stability Criteria ◽

Anisotropic Thermal Conductivity ◽

Operating Current ◽

Released Energy ◽

The Stability ◽

Thermal Stability Of

Intrinsic thermal stability denotes a situation where a superconductor can carry the operating current without resistance at all times after the occurrence of a localized release of thermal energy. This novel stability criterion is different from the cryogenic stability criteria for magnets and has particular relevance to thin-film superconductors. Crystals of ceramic high-temperature superconductors are likely to exhibit anisotropic thermal conductivity. The resultant anisotropy of highly oriented films of superconductors greatly influences their thermal stability. This work presents an analysis for the maximum operating current density that ensures intrinsic stability. The stability criterion depends on the amount of released energy, the Biot number, the aspect ratio, and the ratio of the thermal conductivities in the plane of the film and normal to it.

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Survival of Endocronartium harknessii teliospores in a simulated airborne state

Canadian Journal of Botany ◽

10.1139/b89-122 ◽

1989 ◽

Vol 67 (3) ◽

pp. 928-932 ◽

Cited By ~ 5

Author(s):

Kan-Fa Chang ◽

P. V. Blenis

Keyword(s):

Relative Humidity ◽

Liquid Nitrogen ◽

Long Distance ◽

Spider Webs ◽

Considerable Potential ◽

Good Ability ◽

Endocronartium Harknessii ◽

Spore Longevity ◽

Effects Of Temperature ◽

Increasing Temperature

The effects of temperature and relative humidity (RH) on the survival of Endocronartium harknessii teliospores and the longevity of these spores out of doors during daylight hours were studied. In one experiment, fresh and liquid-nitrogen-stored spores of E. harknessii were impacted onto spider webs or plastic threads and incubated in darkness at temperatures of 6, 15, and 24 °C and RHs of 39 and 98%. Survival was measured after 1, 2, 4, 8, and 16 days. Spore longevity decreased with increasing temperature and was lower at 98 than at 39% RH. In a second experiment, spores were impacted onto spider webs and placed out of doors on clear days. Viability decreased linearly with time and averaged 33% after 12 h. The data suggest that E. harknessii has relatively good ability to survive in an airborne state and thus would have considerable potential for long distance spread.

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Effects of Temperature on Leaf Expansion in Sunflower

Functional Plant Biology ◽

10.1071/pp9820209 ◽

1982 ◽

Vol 9 (2) ◽

pp. 209 ◽

Cited By ~ 19

Author(s):

HM Rawson ◽

JH Hindmarsh

Keyword(s):

Field Studies ◽

Leaf Expansion ◽

Photon Flux ◽

Photon Flux Density ◽

Leaf Position ◽

Leaf Emergence ◽

Temperature Regimes ◽

Effects Of Temperature ◽

Increasing Temperature ◽

Relative Change

Five commercial cultivars of sunflower were grown in cabinets at three temperature regimes, 32/22, 27/17 and 22/12°C, and with 15-h and 11-h photoperiods, and expansion of leaves 5-15 was followed. Leaves appeared faster with increasing temperature (0.022 leaves day-1 °C-1) and with increasing daylength. Areas of individual leaves increased linearly up the plant profile and, although final area per leaf (Amax) decreased with increasing temperature, the relative change was similar for each leaf position. Cultivars maintained their ranking for Amax across temperatures, and these rankings agreed with those in previous field studies. Within each temperature regime, both the expansion rate of leaves and the duration of expansion increased with leaf position. As temperature increased, leaves grew for shorter periods with a change of 1.04 days °C-1, but under the photon flux density used (500 �mol m-2 s-1, or about 25% full sunlight) expansion rates were greatest at the lowest temperature. Expansion rates were only one-third of those in field studies at comparable temperatures, but durations were similar. Cultivars that achieved the largest Amax did so via faster rates of expansion and not via longer durations: only one cultivar differed from the mean (20 days) duration of leaf expansion. All cultivars reached floral initiation progressively earlier with extension of photoperiod from 10 to 15 h, with the change for the most sensitive cultivars being 8 days and for the least sensitive 5 days. Rates of leaf emergence were linked with this sensitivity.

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Thermal Stability of Residual Stresses in Differently Deep Rolled Surface Layers of Steel SAE 1045

Journal of Materials Engineering and Performance ◽

10.1007/s11665-021-05798-x ◽

2021 ◽

Author(s):

Stephanie Saalfeld ◽

Thomas Wegener ◽

Berthold Scholtes ◽

Thomas Niendorf

Keyword(s):

Thermal Stability ◽

Elevated Temperature ◽

Residual Stresses ◽

Elevated Temperatures ◽

Fatigue Behavior ◽

Decisive Role ◽

Deep Rolling ◽

Material Conditions ◽

The Stability ◽

Thermal Stability Of

AbstractThe stability of compressive residual stresses generated by deep rolling plays a decisive role on the fatigue behavior of specimens and components, respectively. In this regard, deep rolling at elevated temperature has proven to be very effective in stabilizing residual stresses when fatigue analysis is conducted at ambient temperature. However, since residual stresses can be affected not only by plastic deformation but also when thermal energy is provided, it is necessary to analyze the influence of temperature and time on the relaxation behavior of residual stresses at elevated temperature. To evaluate the effect of deep rolling at elevated temperatures on stability limits under thermal as well as combined thermo-mechanical loads, the present work introduces and discusses the results of investigations on the thermal stability of residual stresses in differently deep rolled material conditions of the steel SAE 1045.

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