Studies on the Effect of Temperature on Lead Ion in Aqueous Environment based on Pourbaix Diagram

The extent and location of Escherichia coli O157:H7 contamination after intact apples were immersed in cold (2°C) 1% peptone water containing approximately 3 × 107 CFU/ml was assessed using four apple varieties, Golden Delicious, McIntosh, Red Delicious, and Braeburn. Room temperature and refrigerated apples were used to determine the effect of temperature differential on E. coli infiltration. The highest levels of E. coli were associated with the outer core region of the apple, followed by the skin. Apples were subsequently treated by immersing them for 1 min in 2,000 mg/liter sodium hypochlorite, followed by a 1-min tapwater rinse. This treatment reduced pathogen levels by 1- to 3-log cycles but did not eliminate the microorganism, particularly from the outer core region. While E. coli was not detected in the inner core of most apples, warm fruit immersed in cold peptone water occasionally internalized the pathogen. The frequency and extent of internalization of the pathogen was less when cold apples were immersed in cold peptone water. Subsequent dye uptake studies with Golden Delicious apples indicated that approximately 6% of warm apples immersed into a cold dye solution accumulated dye via open channels leading from the blossom end into the core region. However, dye uptake did not occur when the dye solution was warmer than the apple.

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The Effect of Temperature and Cyclic Frequency Upon Fatigue Crack Growth Behavior of Several Steels in an Elevated Temperature Aqueous Environment

Journal of Pressure Vessel Technology ◽

10.1115/1.2929565 ◽

1994 ◽

Vol 116 (2) ◽

pp. 122-127 ◽

Cited By ~ 16

Author(s):

L. A. James

Keyword(s):

Fatigue Crack ◽

Elevated Temperature ◽

Time Domain ◽

Nuclear Industry ◽

Effect Of Temperature ◽

Crack Growth Behavior ◽

Aqueous Environment ◽

Hydrogen Electrode ◽

Cyclic Frequency ◽

The Time Domain

The fatigue crack propagation (FCP) behavior of several ASTM A302-B and A508-2 steels was characterized in deaerated elevated temperature aqueous environment. FCP behavior was determined over the range 121°C to 343°C at a constant value of ΔK, stress ratio, and load rise time. A complex response of FCP rates as a function of temperature was observed, and this is discussed in the light of similar results developed by others within the nuclear industry. Corrosion potentials (referenced to the standard hydrogen electrode) were measured for each of the steels over the above temperature range and comparisons are made to the observed FCP behavior. Cyclic frequency effects were studied at two temperatures, 149°C and 243°C, and these are analyzed within the “time domain” format first suggested by Shoji et al. The results, when expressed in the time domain format, clearly show regions where environmentally assisted cracking (EAC) occurs, and regions where EAC does not occur. A “threshold” for EAC was noted at 149°C, and the possibility of an EAC threshold was observed at 243°C.

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Biosorption of lead ion from aqueous environment using wheat stem biomass

10.5004/dwt.2021.27518 ◽

2021 ◽

Vol 233 ◽

pp. 98-105

Author(s):

Ali Jalali ◽

Fakhrosadat Mirnezami ◽

Marzieh Lotfi ◽

Mojtaba Shafiee ◽

Amir H Mohammadi

Keyword(s):

Lead Ion ◽

Aqueous Environment ◽

Stem Biomass

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Effect of Temperature on the Properties of Poly(Vinylpyrrolidone)-Iron Magnetic Nanocomposite for Oil Recovery

Nano Hybrids and Composites ◽

10.4028/www.scientific.net/nhc.31.73 ◽

2021 ◽

Vol 31 ◽

pp. 73-80

Author(s):

Muhammad Syafiq Aiman Abd Rahman ◽

Noor Farah Nazirah Norsamsuddin ◽

Nurul Hafizah Muhamad Tajuddin ◽

S.M. Shahrul Nizan Shikh Zahari ◽

Sofina Tamam

Keyword(s):

Oil Recovery ◽

Ammonia Solution ◽

Magnetic Nanocomposite ◽

Effect Of Temperature ◽

Aqueous Environment ◽

Significant Finding ◽

Water Mixture ◽

Water Separation ◽

Different Temperatures ◽

Oil Water

The poly (vinylpyrrolidone)-iron magnetic nanocomposite (PVP-Fe NCs) recently used for oil recovery since it capable to remove up to 80% of oil. However, the magnetic properties PVP-Fe NCs might not be consistently performed as it has a tendency to having low magnetism depending on their temperature. This study aims to investigate the effect of temperature of PVP-Fe NCs, to see the effectiveness of oil recovery from aqueous environment by using magnetic decantation method. The PVP-iron magnetic was synthesized by three steps using poly (vinylpyrrolidone), FeCl2•4H2O, FeCl3•6H2O and ammonia solution involving mixing and heating, precipitating and separating. The oil removal was tested by mixing the PVP-Fe NCs into an oil-water mixture to let it coat by oil. The oil-water separation was conducted by using a neodymium magnet. The experiments were repeated using the same PVP-materials with different temperatures such as room temperature, 50°C, 80°C and 90°C. The presence of OH-1 group and the magnetic property of each samples was characterized by using FTIR and VSM. The study reveals that the PVP-Fe NCs have highest magnetism at 80°C compared to other temperatures. 80°C seem to be the optimum temperature to perform the good magnetism of PVP-Fe NCs since it reduces its magnetism at 90°C due to its thicker coat. The also showed that PVP-Fe3 are hydrophilic that can assist in oil separation from water. This study demonstrated a significant finding in oil recovery application using PVP-iron magnetic nanocomposites materials.

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The Influence of Initiator Concentration on Selected Properties of Thermosensitive Poly(Acrylamide-co-2-Acrylamido-2-Methyl-1-Propanesulfonic Acid) Microparticles

Polymers ◽

10.3390/polym13070996 ◽

2021 ◽

Vol 13 (7) ◽

pp. 996

Author(s):

Agnieszka Gola ◽

Andrea Bernardi ◽

Gianfranco Pasut ◽

Witold Musiał

Keyword(s):

Light Scattering ◽

Dynamic Light Scattering ◽

1H Nmr ◽

Effect Of Temperature ◽

Hydrodynamic Diameter ◽

Aqueous Environment ◽

Initiator Concentration ◽

Polymeric Particles ◽

Temperature Solution ◽

Dta Curves

Thermosensitive polymers PS1–PS5 were synthesized via the surfactant free precipitation polymerization (SFPP) using 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPSA), and potassium persulfate (KPS) at 70 °C in aqueous environment. The effect of KPS concentrations on particle size and lower critical temperature solution (LCST) was examined by dynamic light scattering (DLS). The conductivity in the course of the synthesis and during cooling were investigated. The structural studies were performed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), H nuclear magnetic resonance (1H NMR), thermogravimetric analysis (TGA/DTA) and powder X-ray diffraction (PXRD). ATR-FTIR, 1H NMR and PXRD data confirmed the polymeric nature of the material. TGA/DTA curves demonstrated thermal stability up to approx. 160 °C. The effect of temperature on the hydrodynamic diameter (HD) and zeta potential (ZP) were evaluated by dynamic light scattering (DLS) and electrophoretic mobility (EM) in 18–45 °C range. The LCST values were between 30 and 34 °C. HD and polydispersity index (PDI) of aqueous dispersions of the synthesized polymers PS1–PS5 at 18 °C were found to be 226 ± 35 nm (PDI = 0.42 ± 0.04), 299 ± 145 nm (PDI = 0.49 ± 0.29), 389 ± 39 nm (PDI = 0.28 ± 0.07), 584 ± 75 nm (PDI = 0.44 ± 0.06), and 271 ± 50.00 nm (PDI = 0.26 ± 0.14), respectively. At 18 °C the ZPs of synthesized polymers suspensions were −13.14 ± 2.85 mV, −19.52 ± 2.86 mV, −7.73 ± 2.76 mV, −7.99 ± 1.70 mV, and −9.05 ± 2.60 mV for PS1–PS5, respectively. We found that the initiator concentration influences the physicochemical properties of products including the size of polymeric particles and the LCST.

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Nucleation of Disorder in Fe3Al Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061574 ◽

1967 ◽

Vol 25 ◽

pp. 312-313

Author(s):

P. R. Swann ◽

W. R. Duff ◽

R. M. Fisher

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Annealing Temperature ◽

Antiphase Domain ◽

Effect Of Temperature ◽

Domain Structures ◽

Transmission Electron ◽

Domain Boundaries ◽

Higher Temperature ◽

The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

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The effect of temperature on high-resolution TEM image contrast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139573 ◽

1995 ◽

Vol 53 ◽

pp. 640-641

Author(s):

T. Geipel ◽

W. Mader ◽

P. Pirouz

Keyword(s):

Form Factor ◽

Inelastic Scattering ◽

Accurate Method ◽

Waller Factor ◽

Effect Of Temperature ◽

Specimen Thickness ◽

Influence Of Temperature ◽

Debye Waller Factor ◽

Influence Of Temperature On ◽

Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

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Prospects for scanned-probe microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167767 ◽

1994 ◽

Vol 52 ◽

pp. 6-7

Author(s):

Jean-Paul Revel

Keyword(s):

High Vacuum ◽

Physiological Saline ◽

Scanning Probe ◽

Aqueous Environment ◽

Whole Cells ◽

Material Scientist ◽

Biological Objects ◽

Spatially Resolved ◽

Atomic Force ◽

Scanned Probe Microscopy

In the last 50+ years the electron microscope and allied instruments have led the way as means to acquire spatially resolved information about very small objects. For the material scientist and the biologist both, imaging using the information derived from the interaction of electrons with the objects of their concern, has had limitations. Material scientists have been handicapped by the fact that their samples are often too thick for penetration without using million volt instruments. Biologists have been handicapped both by the problem of contrast since most biological objects are composed of elements of low Z, and also by the requirement that sample be placed in high vacuum. Cells consist of 90% water, so elaborate precautions have to be taken to remove the water without losing the structure altogether. We are now poised to make another leap forwards because of the development of scanned probe microscopies, particularly the Atomic Force Microscope (AFM). The scanning probe instruments permit resolutions that electron microscopists still work very hard to achieve, if they have reached it yet. Probably the most interesting feature of the AFM technology, for the biologist in any case, is that it has opened the dream of high resolution in an aqueous environment. There are few restrictions on where the instrument can be used. AFMs can be made to work in high vacuum, allowing the material scientist to avoid contamination. The biologist can be made happy as well. The tips used for detection are made of silicon nitride,(Si3N4), and are essentially unaffected by exposure to physiological saline (about which more below). So here is an instrument which can look at living whole cells and at atoms as well.

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