Effects of pH and heat treatment on the stability of γ‐aminobutyric acid (GABA) in germinated soymilk

SUMMARYFor milk from four herds of cows, maintained under different conditions of feeding and management, the natural Cu content and the stability of the ascorbate were highly correlated. Low Cu levels in milk from cows at pasture at farms A and B during the summer were associated with low storage losses of ascorbate. During this period, the milk of cows at farms C and D (on forage and Cu-supplemented concentrate) was richer in Cu, and losses of ascorbate were high. Heat treatment of the milk stabilized the ascorbate. Thus, in ‘high Cu’ milk (60 µg Cu/l), loss of ascorbate in the raw milk was 58% at 2 d, as against 17% after pasteurization at 72 °C and no loss after treatment at 82 °C. Storage of milk in light caused rapid destruction of ascorbate, equally with 72 and 82 °C heat treatments. The effects were examined of milk pasteurization temperature (72–82 °C) on flavour stability, bacteriological quality and vitamins of the B-complex. Heat treatment at 82 °C increased the susceptibility of vitamin B12 to destruction by light, but otherwise caused no greater losses of B-complex vitamins than did treatment at 72 °C. Taste panel ratings showed an initial preference for milk heated at 72 °C, but on storage of this milk in darkness the flavour score fell progressively and at 5 d it was judged ‘stale’. Treatment at 82 °C gave a faint ‘cooked’ flavour although, unlike that of the 72 °C-treated milk, the flavour remained stable throughout 14-d storage and after d 8 was increasingly preferred. On exposure to light after treatment at 72 °C milks rapidly acquired an unpleasant‘oxidized’ flavour, but after treatment at 82 °C, exposure to light had no such adverse effect on flavour during the early days of storage. Pasteurization at ∼ 80 °C offers a potential for improvement in the oxidative stability of milk and its contribution of vitamin C to the diet.

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Effects of Stress and Plastic Deformation on the Corrosion of Steel

CORROSION ◽

10.5006/0010-9312-26.5.189 ◽

1970 ◽

Vol 26 (5) ◽

pp. 189-199 ◽

Cited By ~ 17

Author(s):

W. D. FRANCE

Keyword(s):

Plastic Deformation ◽

Electrochemical Techniques ◽

Chloride Ions ◽

Localized Corrosion ◽

Dissolution Behavior ◽

Potential Range ◽

Chemical Corrosion ◽

Effects Of Ph ◽

Current Densities ◽

The Stability

Abstract The rate and type of corrosion exhibited by mild steel in the annealed, stressed, and plastically deformed state have been investigated. Precise electrochemical techniques provided potential and polarization data to supplement the results of chemical corrosion tests. Experiments were conducted in 0.6M NH4NO3 solutions in which steel exhibits active-passive dissolution behavior as well as localized corrosion. At active potentials, the anodic polarization curves for annealed and deformed specimens were nearly identical, with only slight increases in current densities for the deformed steel. Results at passive potentials demonstrated that increased plastic deformation can markedly decrease the passive potential range, the stability of passivity, and the ability to passivate. At certain passive potentials, the deformed steel exhibited current densities that were 400 times greater than those for annealed steel. The effects of pH, chloride ions, and crevices on the corrosion of deformed steel were examined in detail. The differences between the dissolution behavior of annealed and deformed steel were most distinctive in the approximate pH range of 3 to 6. This work is relevant to the understanding of the initiation of localized corrosion and to anodic protection.

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Synthesis and characterization of one-dimensional titanate structure

Processing and Application of Ceramics ◽

10.2298/pac0802109n ◽

2008 ◽

Vol 2 (2) ◽

pp. 109-114 ◽

Cited By ~ 13

Author(s):

Ljubica Nikolic ◽

Marija Maletin ◽

Paula Ferreira ◽

Paula Vilarinho

Keyword(s):

Heat Treatment ◽

Structural Characteristics ◽

Hydrothermal Process ◽

Synthesis And Characterization ◽

One Dimensional ◽

Treatment Conditions ◽

Alkaline Conditions ◽

The Stability ◽

Simple Hydrothermal Process

One-dimensional titania structures were synthesized trough a simple hydrothermal process in a highly alkaline conditions. The aim of this work was to elucidate the effect of time on the formation of 1D titanates as well on its structural characteristics (morphology, phase composition, surface area). Apart from that, the effect of heat treatment conditions on the stability of titanate based 1D samples has been investigated. The results have revealed that it is possible to form one-dimensional titanates already after 1 hour of hydrothermal synthesis. Although the composition of titanates is still under debate, the results probably correspond to the layered sodium titanates. The 1D prepared structures show a remarkable stability during heating, remaining the basic morphology and composition even up to 700?C.

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Effects of pH and Electrolytes on Castor Oil Emulsions with Various Stabilisers Using Khaya senegalensis Gum as an Emulsifier

Advances in Pharmacological and Pharmaceutical Sciences ◽

10.1155/2021/7049332 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Deryl Nii Okantey Kuevi ◽

Noble Kuntworbe ◽

Enoch Ayertey

Keyword(s):

Castor Oil ◽

Xanthan Gum ◽

Hydroxypropyl Methylcellulose ◽

Physical Stability ◽

Tween 80 ◽

Volume Data ◽

Emulsifying Property ◽

Khaya Senegalensis ◽

Effects Of Ph ◽

The Stability

Dispersed systems such as emulsions are easily destabilised during processing and storage since they are thermodynamically unstable systems. It is for this reason emulsifiers/stabilisers are frequently employed in pharmaceutical emulsion formulations to increase their short- and long-term kinetic stability. This current study seeks to investigate the potential emulsifying property of gums obtained from Khaya senegalensis (family: Meliaceae) trees. Gums were collected, authenticated, oven-dried, milled, filtered, and purified using 96% ethanol. The microbial quality of the gum was assessed following the BP (2013) specifications. The purified gum was free from some selected pathogenic microorganisms, rendering the gum safe for consumption. The emulsifying property was investigated by formulating emulsions using castor oil and employing the dry gum method. The ratios of oil-to-water-to-gum for the formulation of a stable emulsion were determined. The stability of the emulsion was evaluated, and an effort was made to improve the stability by incorporating Tween 80, hydroxypropyl methylcellulose, and xanthan gum. From the results, it can be inferred that Tween 80 (0.5%) was able to stabilise the emulsion. Addition of xanthan gum worsened the creaming. The effects of pH (4.0, 5.5, 7.2, 9.0, and 11.0) and electrolytes (0.1 M of NaCl, KCl, and CaCl2) on the physical stability of oil-in-water emulsions were studied during 12 weeks of storage. Percentage creaming volume and whether there was phase inversion were the criteria used as the evaluation parameter. From the percentage creaming volume data, emulsions formulated with both gums showed the lowest creaming volumes at pH of 7.2, followed by the acidic regions (pH 4.0, 5.5), with the basic regions (pH 9.0, 11.0) recording the highest creaming volumes. The effects of the various electrolytes at a constant concentration of 0.1 M on the o/w emulsions were found in this order NaCl < KCl < CaCl2. This study proves that Khaya senegalensis gum can successfully be employed as an emulsifying agent in pharmaceutical formulations.

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Carbonitration of a Tool for Pressing Stainless Steel Pipes

Journal of Engineering Sciences ◽

10.21272/jes.2020.7(2).c3 ◽

2020 ◽

Vol 7 (2) ◽

pp. C17-C21

Author(s):

I. V. Ivanov ◽

M. V. Mohylenets ◽

K. A. Dumenko ◽

L. Kryvchyk ◽

T. S. Khokhlova ◽

...

Keyword(s):

Heat Treatment ◽

Thermal Treatment ◽

Heat Resistance ◽

Alkali Metals ◽

Matrix Ring ◽

High Hardness ◽

Operating Conditions ◽

Matrix Rings ◽

Conventional Heat Treatment ◽

The Stability

To upgrade the operational stability of the tool at LLC “Karbaz”, Sumy, Ukraine, carbonation of tools and samples for research in melts of salts of cyanates and carbonates of alkali metals at 570–580 °C was carried out to obtain a layer thickness of 0.15–0.25 mm and a hardness of 1000–1150 НV. Tests of the tool in real operating conditions were carried out at the press station at LLC “VO Oscar”, Dnipro, Ukraine. The purpose of the test is to evaluate the feasibility of carbonitriding of thermo-strengthened matrix rings and needle-mandrels to improve their stability, hardness, heat resistance, and endurance. If the stability of matrix rings after conventional heat setting varies around 4–6 presses, the rings additionally subjected to chemical-thermal treatment (carbonitration) demonstrated the stability of 7–9 presses due to higher hardness, heat resistance, the formation of a special structure on the surface due to carbonitration in salt melts cyanates and carbonates. Nitrogen and carbon present in the carbonitrided layer slowed down the processes of transformation of solid solutions and coagulation of carbonitride phases. The high hardness of the carbonitrified layer is maintained up to temperatures above 650 °C. If the stability of the needle-mandrels after conventional heat treatment varies between 50–80 presses, the needles, additionally subjected to chemical-thermal treatment (carbonitration) showed the stability of 100–130 presses due to higher hardness, wear resistance, heat resistance, the formation of a special surface structure due to carbonitration in melts of salts of cyanates and carbonates. Keywords: needle-mandrel, matrix ring, pressing, heat treatment, carbonitration.

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Effect of Heat-Treatment Time on Microstructure and Mechanical Properties of Mg-5Gd-2Y-2Zn-0.5Zr Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.482-484.1384 ◽

2012 ◽

Vol 482-484 ◽

pp. 1384-1389 ◽

Cited By ~ 1

Author(s):

Ling Gang Meng ◽

Can Feng Fang ◽

Peng Peng ◽

Nai Pu Li ◽

Qiong Zhu ◽

...

Keyword(s):

Heat Treatment ◽

Grain Boundary ◽

Treatment Time ◽

Time Range ◽

Lpso Phase ◽

High Temperature Heat Treatment ◽

Lpso Structure ◽

The Matrix ◽

New Type ◽

The Stability

Microstructure evolution of Mg-5Gd-2Y-2Zn-0.5Zr alloy during high temperature heat-treatment at 500°C in the time range 10-70h was investigated. The results show that after adding the element Y, the as-cast Mg-5Gd-2Y-2Zn-0.5Zr alloy forms the Mg12Zn(Y,Gd) phase with 18R-LPSO structure at the grain boundary. During heat-treatment at 500°C, the stability of 18R-LPSO structure is weakened by Gd atoms, parts of LPSO phases dissolve gradually into the matrix with time prolonged and a new type Mg(Y,Gd)Zn phase come into being. LPSO phase in the grain boundary can ensure the ultimate tensile strength and elongation of the alloy, and effect of dissevering on the LPSO phase by Mg(Gd,Y)Zn phase results the decrease of UTS and elongation.

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Effect of Preliminary Heat Treatment on the Stability of Austenite in Steel 08Kh15N5D2T

Metal Science and Heat Treatment ◽

10.1007/s11041-005-0057-8 ◽

2005 ◽

Vol 47 (5-6) ◽

pp. 232-234

Author(s):

T. M. Makhneva ◽

S. F. Savchenkova ◽

E. S. Makhnev ◽

M. V. Savchenkova

Keyword(s):

Heat Treatment ◽

Preliminary Heat Treatment ◽

The Stability

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Screening for drugs of abuse: effect of heat-treating urine for safe handling of samples

Clinical Chemistry ◽

10.1093/clinchem/36.6.908 ◽

1990 ◽

Vol 36 (6) ◽

pp. 908-910 ◽

Cited By ~ 3

Author(s):

K Wolff ◽

M A Shanab ◽

M J Sanderson ◽

A W Hay

Keyword(s):

Heat Treatment ◽

Human Immunodeficiency Virus ◽

Drugs Of Abuse ◽

Heat Treating ◽

Immunodeficiency Virus ◽

Aids Virus ◽

Risk Patients ◽

Higher Temperature ◽

Abused Drugs ◽

The Stability

Abstract Heating urine samples from high-risk patients for 1 h at 56 degrees C is no longer believed to completely inactivate human immunodeficiency virus (HIV; AIDS virus). To protect staff who are handling infectious samples such as those from drug-addiction units, heating at a higher temperature may be necessary. We report the stability to heat treatment (at 60, 70, and 100 degrees C) at pH 5.1 and 7.6 of some commonly abused drugs, namely, methadone, pethidine, amphetamine, the cocaine metabolite, benzoylecgonine, and the dextropropoxyphene metabolite nordextropropoxyphene. Heat-treating urine at 60 degrees C for 1.5 h or 70 degrees C for 1 h did not significantly affect the measured concentrations of these drugs. However, heat treatment at 100 degrees C for 1 h reduced the recovery of all the drugs. Benzoylecgonine and amphetamine were most susceptible to the different forms of heat treatment.

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The Stability of γ ’-Co3(Al,W) Phase in Co-Al-W Ternary System

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.448 ◽

2010 ◽

Vol 654-656 ◽

pp. 448-451 ◽

Cited By ~ 37

Author(s):

Yuki Tsukamoto ◽

Satoru Kobayashi ◽

Takayuki Takasugi

Keyword(s):

Heat Treatment ◽

Ternary System ◽

Microstructural Evolution ◽

Treatment Time ◽

Bulk Alloy ◽

Epma Analysis ◽

Heat Treated ◽

Cold Rolled ◽

The Stability ◽

Couple Method

The thermodynamic stability ’- Co3(Al,W) phase (L12) in the Co-Al-W ternary system at 900 °C was investigated through microstructure and EPMA analysis on a heat-treated bulk alloy. To promote microstructural evolution, the bulk alloy was cold rolled before heat treatment. By heating at 900 °C, the ’ phase was formed discontinuously in contact with the -Co (A1) phase. With increasing heat treatment time, however, the fraction of ’ phase decreased while that of , CoAl (B2) and Co3W (D019) phases increased. These results are consistent with our previous work with a diffusion-couple method, indicating that the ’ phase is metastable, and the three phases of, CoAl and Co3W are thermodynamically stable at 900 °C.

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