Inactivation Effects of UV Irradiation and Ozone Treatment on the Yeast and the Mold in Mineral Water

2010 ◽  
Vol 73 (8) ◽  
pp. 1537-1542 ◽  
Author(s):  
M. WATANABE ◽  
H. MASAKI ◽  
T. MORI ◽  
T. TSUCHIYA ◽  
H. KONUMA ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Uv Irradiation ◽  
Mineral Water ◽  
Treatment Time ◽  
Yeast Cells ◽  
Ozone Treatment ◽  
Log Reduction ◽  
Definite Effect ◽  
Yeasts And Molds ◽  
Bottled Mineral Water

In recent years, bottled mineral water has undergone inactivation by methods other than the traditional heat treatment during the production process; there are fewer reports of the effectiveness of these inactivation methods on yeasts and molds in mineral water than on bacteria and protozoan oocysts. In this study, we evaluated the effects of UV irradiation and ozone treatment compared with heat treatment at 85°C on yeast cells and mold spores inoculated into mineral water. A 5-log reduction occurred at a UV radiation dose of 31,433 μJ/cm2 for Saccharomyces cerevisiae and at 588,285 μJ/cm2 for Penicillium pinophilum. The treatment time for 5-log reduction estimated for UV irradiation was about 0.6 min for S. cerevisiae and about 10.7 min for P. pinophilum; at an ozone concentration of 0.1 ppm, it was 1.75 min for S. cerevisiae and 2.70 min for P. pinophilum, and at a concentration of 0.6 ppm, it was 0.32 min for S. cerevisiae and 0.57 min for P. pinophilum. Comparison of the inactivation effects among the three methods showed that UV irradiation and ozone treatment were less effective than heat treatment at 85°C. Thus, when UV irradiation and ozone treatment are used for inactivation of mineral water, it seems that they need to be combined with heat treatment to achieve a definite effect. Yeast cells are more sensitive to all three inactivation methods than are mold spores, and the sensitivity of yeast cells and mold spores to these inactivation methods may vary among genera.

scholarly journals Influence of Rapid Heat Treatment on the Shrinkage and Strength of High-Performance Concrete

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4102
Author(s):  
Jan Stindt ◽  
Patrick Forman ◽  
Peter Mark
Keyword(s):  
Heat Treatment ◽  
High Performance ◽  
High Performance Concrete ◽  
Treatment Time ◽  
Precast Concrete ◽  
Concrete Strength ◽  
Shrinkage Strain ◽  
Temperature Treatment ◽  
Production Flow ◽  
Steel Fibres

Resource-efficient precast concrete elements can be produced using high-performance concrete (HPC). A heat treatment accelerates hardening and thus enables early stripping. To minimise damages to the concrete structure, treatment time and temperature are regulated. This leads to temperature treatment times of more than 24 h, what seems too long for quick serial production (flow production) of HPC. To overcome this shortcoming and to accelerate production speed, the heat treatment is started here immediately after concreting. This in turn influences the shrinkage behaviour and the concrete strength. Therefore, shrinkage is investigated on prisms made from HPC with and without steel fibres, as well as on short beams with reinforcement ratios of 1.8% and 3.1%. Furthermore, the flexural and compressive strengths of the prisms are measured directly after heating and later on after 28 d. The specimens are heat-treated between 1 and 24 h at 80 °C and a relative humidity of 60%. Specimens without heating serve for reference. The results show that the shrinkage strain is pronouncedly reduced with increasing temperature duration and rebar ratio. Moreover, the compressive and flexural strength decrease with decreasing temperature duration, whereby the loss of strength can be compensated by adding steel fibres.

scholarly journals Deep-Ultraviolet Transparent Conductive MWCNT/SiO2 Composite Thin Film Fabricated by UV Irradiation at Ambient Temperature onto Spin-Coated Molecular Precursor Film

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1348
Author(s):  
Hiroki Nagai ◽  
Naoki Ogawa ◽  
Mitsunobu Sato
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Heat Treatment ◽  
Uv Irradiation ◽  
Composite Thin Film ◽  
Precursor Film ◽  
Mixed Solution ◽  
Pencil Hardness ◽  
Strong Base ◽  
Deep Ultraviolet

Deep-ultraviolet (DUV) light-transparent conductive composite thin films, consisting of dispersed multiwalled carbon nanotubes (MWCNTs) and SiO2 matrix composites, were fabricated on a quartz glass substrate. Transparent and well-adhered amorphous thin films, with a thickness of 220 nm, were obtained by weak ultraviolet (UV) irradiation (4 mW cm−2 at 254 nm) for more than 6 h at 20−40 °C onto the precursor films, which were obtained by spin coating with a mixed solution of MWCNT in water and Si(IV) complex in ethanol. The electrical resistivity of MWCNT/SiO2 composite thin film is 0.7 Ω·cm, and transmittance in the wavelength region from DUV to visible light is higher than 80%. The MWCNT/SiO2 composite thin film showed scratch resistance at pencil hardness of 8H. Importantly, the resistivity of the MWCNT/SiO2 composite thin film was maintained at the original level even after heat treatment at 500 °C for 1 h. It was observed that the heat treatment of the composite thin film improved durability against both aqueous solutions involving a strong acid (HCl) and a strong base (NaOH).

scholarly journals Pulsed Electric Field (PEF) Enhances Iron Uptake by the Yeast Saccharomyces cerevisiae

Biomolecules ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 850
Author(s):  
Karolina Nowosad ◽  
Monika Sujka ◽  
Urszula Pankiewicz ◽  
Damijan Miklavčič ◽  
Marta Arczewska
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Electric Field ◽  
Metal Ion ◽  
Treatment Time ◽  
Control Sample ◽  
Pulsed Electric Field ◽  
Yeast Cells ◽  
Iron Ions ◽  
Metal Ion Binding ◽  
Yeast Saccharomyces Cerevisiae

The aim of the study was to investigate the influence of a pulsed electric field (PEF) on the level of iron ion accumulation in Saccharomyces cerevisiae cells and to select PEF conditions optimal for the highest uptake of this element. Iron ions were accumulated most efficiently when their source was iron (III) nitrate. When the following conditions of PEF treatment were used: voltage 1500 V, pulse width 10 μs, treatment time 20 min, and a number of pulses 1200, accumulation of iron ions in the cells from a 20 h-culture reached a maximum value of 48.01 mg/g dry mass. Application of the optimal PEF conditions thus increased iron accumulation in cells by 157% as compared to the sample enriched with iron without PEF. The second derivative of the FTIR spectra of iron-loaded and -unloaded yeast cells allowed us to determine the functional groups which may be involved in metal ion binding. The exposure of cells to PEF treatment only slightly influenced the biomass and cell viability. However, iron-enriched yeast (both with or without PEF) showed lower fermentative activity than a control sample. Thus obtained yeast biomass containing a high amount of incorporated iron may serve as an alternative to pharmacological supplementation in the state of iron deficiency.

Effect of Chlorine Dioxide Gas Treatment on Surface Sterilization of Grape

2011 ◽  
Vol 236-238 ◽  
pp. 2939-2944 ◽  
Author(s):  
Ri Ya Jin ◽  
Shuang Qi Hu ◽  
Zhi Chao Chi
Keyword(s):  
Chlorine Dioxide ◽  
Treatment Time ◽  
Reducing Sugar ◽  
Gas Treatment ◽  
Surface Sterilization ◽  
Log Reduction ◽  
Chlorine Dioxide Gas ◽  
Spoilage Bacteria ◽  
Effect Of Chlorine

Experiments were conducted to investigate the effect of concentration and duration of chlorine dioxide gas treatment on Surface sterilization of grape at 25°C. The results showed that the values of inactivate bacterial log reduction ofBotrytis cinerea,Penicilliumandalternariaincreased with the increasing of ClO2gas concentrations and treatment time. When the concentrations and treatment time was about 10 mg/m3and 30 minutes, respectively, more than 4 log reduction was obtained for the three spoilage bacteria on grape surface. Furthermore, the effect of chlorine dioxide gas treatment on quality of grape was investigated. It was found that the contents of vitamin C (Vc) and reducing sugar (RS) in grape also increased compared with grape without ClO2gas treatment.

The Effect of Aging Heat Treatment on the Microstructure and Mechanical Properties of 10Cr20Ni25Mo1.5NbN Austenitic Steel

2016 ◽  
Vol 35 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Zhiyuan Liang ◽  
Wanhua Sha ◽  
Qinxin Zhao ◽  
Chongbin Wang ◽  
Jianyong Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Heat Treatment ◽  
Austenitic Steel ◽  
Treatment Time ◽  
Aging Treatment ◽  
Secondary Phases ◽  
Aging Heat Treatment ◽  
Microstructure And Mechanical Properties ◽  
The Impact

AbstractThe effect of aging heat treatment on the microstructure and mechanical properties of 10Cr20Ni25Mo1.5NbN austenitic steel was investigated in this article. The microstructure was characterized by scanning electron microscopy, energy dispersive spectrometry and transmission electron microscopy. Results show that the microstructure of 10Cr20Ni25Mo1.5NbN austenitic is composed of austenite. This steel was strengthened by precipitates of secondary phases that were mainly M23C6 carbides and NbCrN nitrides. As aging treatment time increased, the tensile strength first rose (0–3,000 h) and then fell (3,000–5,000 h) due to the decrease of high density of dislocations. The impact absorbed energy decreased sharply, causing the sulfides to precipitate at the grain boundary. Therefore, the content of sulfur should be strictly controlled in the steelmaking process.

Radiation dose to the Malaysian populace via the consumption of bottled mineral water

2017 ◽  
Vol 140 ◽  
pp. 173-179 ◽  
Author(s):  
Mayeen Uddin Khandaker ◽  
Noor Liyana Mohd Nasir ◽  
Nur Syahira Zakirin ◽  
Hasan Abu Kassim ◽  
Khandoker Asaduzzaman ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Mineral Water ◽  
Bottled Mineral Water

scholarly journals Enhanced aging kinetics in Al-Mg-Si alloys by up-quenching

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Florian Schmid ◽  
Philip Dumitraschkewitz ◽  
Thomas Kremmer ◽  
Peter J. Uggowitzer ◽  
Ramona Tosone ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Treatment Time ◽  
Cluster Formation ◽  
High Strength ◽  
Second Phase ◽  
Second Phase Particles ◽  
Negative Effect ◽  
High Elongation ◽  
Aging Kinetics ◽  
Complex Parts

AbstractPrecipitation-hardened aluminium alloys typically obtain their strength by forming second-phase particles, which, however, often have a negative effect on formability. To enable both lightweight construction and forming of complex parts such as body panels, high strength and formability are required simultaneously. Cluster hardening is a promising approach to achieve this. Here, we show that short thermal spikes, denoted as up-quenching, increase aging kinetics, which we attribute to the repeated process of vacancies being formed at high temperatures and retained when cooled to lower temperatures. Combined with further heat treatment, the up-quenching process promotes rapid and extensive cluster formation in Al-Mg-Si alloys, which in turn generates significant strengthening at industrially relevant heat treatment time scales. The high elongation values also observed are attributed to reduced solute depleted zones along grain boundaries.

Synthesis and Characterization of Mnbi Magnetic Alloy via Two Different Processing Routes

2021 ◽  
Vol 875 ◽  
pp. 76-80
Author(s):  
Hifsa Mazhar ◽  
Wilayat Hussain
Keyword(s):  
Heat Treatment ◽  
Melt Spinning ◽  
Treatment Time ◽  
Magnetic Energy ◽  
Microstructural Characterization ◽  
Temperature Phase ◽  
Magnetic Alloy ◽  
Positive Temperature ◽  
Melt Spinning Technique

Manganese bismuth alloy has gained importance due to its rare earth free elements, positive temperature coefficient and unique magnetic properties. Low temperature phase (LTP) MnBi was successfully prepared by arc melting with subsequent heat treatments and melt spinning technique followed by heat treatment for different durations. LTP MnBi formation was confirmed using XRD analysis and microstructural characterization of the samples was done using field emission scanning electron microscope. MnBi with greater LTP amount was formed by melt spinning route when compared with its counter arc melted one. Magnetic energy density of LTP MnBi formed by melt spinning technique with different heat treatment time was studied.

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