Changes in fungal populations during storage of Dalbergia bark

1981 ◽  
Vol 59 (6) ◽  
pp. 1102-1106
Author(s):  
D. K. Sandhu ◽  
D. S. Arora
Keyword(s):  
Aspergillus Nidulans ◽  
Common Species ◽  
Temperature Range ◽  
Colony Forming Units ◽  
Wide Range ◽  
Fungal Populations

Nineteen species of fungi were isolated during a 16-week successional study on Dalbergia bark. The most common species present throughout the succession were Aspergillus nidulans and A. fumigatus. Maximum colony forming units (CFU) were recorded during the 3rd week. The highest temperature recorded during the succession was 47 °C. In culture, most of the fungi showed a wide range of temperatures for growth, i.e. 15–47 °C; some were confined to a temperature range of 15–37 °C or 15–32 °C. Most of the fungi, except Acrophialophora fusispora, could utilize cellulose. Only seven fungi showed some lignin utilizing capacity.

Enabling highly reversible sodium metal cycling across a wide temperature range with dual-salt electrolytes

2021 ◽  
Author(s):  
Akila C. Thenuwara ◽  
Pralav P. Shetty ◽  
Neha Kondekar ◽  
Chuanlong Wang ◽  
Weiyang Li ◽  
...  
Keyword(s):  
Wide Temperature Range ◽  
High Energy ◽  
Liquid Electrolyte ◽  
Metal Cycling ◽  
Temperature Range ◽  
Sodium Metal ◽  
Wide Range

A new dual-salt liquid electrolyte is developed that enables the reversible operation of high-energy sodium-metal-based batteries over a wide range of temperatures down to −50 °C.

Temperature studies of iron-oxidizing autotrophs and acidophilic heterotrophs isolated from uranium mines

1993 ◽  
Vol 39 (4) ◽  
pp. 384-388 ◽  
Author(s):  
Deborah Berthelot ◽  
L. G. Leduc ◽  
G. D. Ferroni
Keyword(s):  
Water Samples ◽  
Mine Water ◽  
Thiobacillus Ferrooxidans ◽  
Incubation Temperature ◽  
Temperature Growth ◽  
Temperature Range ◽  
Uranium Mines ◽  
Iron Oxidizing Bacteria ◽  
Colony Forming Units ◽  
Growth Profiles

Iron-oxidizing autotrophs and acidophilic heterotrophs were quantified at an incubation temperature of 18 °C in several samples obtained from the bioleaching areas of two uranium mines in Ontario, Canada. All samples were mine-water samples with temperatures in the range 13–18 °C. Iron-oxidizing autotrophs ranged from 2683 ± 377 to 245 000 ± 20 205 colony-forming units∙mL−1 and were always numerically superior to acidophilic heterotrophs, which ranged from 40 ± 8 to 9650 ± 161 colony-forming units∙mL−1. For each sample, approximately 20 isolates of each nutritional group were examined for the ability to grow at temperatures of 4, 18, 21, and 37 °C, respectively; overall, 559 isolates of iron-oxidizing bacteria (predominantly Thiobacillus ferrooxidans) and 252 acidophilic heterotrophic isolates were examined and categorized as 'broader temperature range psychrotrophs,' 'narrower temperature range psychrotrophs,' 'intermediates,' or mesophiles. Although psychrotrophic representatives of both groups were abundant, no psychrophiles were recovered from any of the samples. For the iron oxidizers, the temperature growth profiles of the isolates were similar from sample to sample. For the acidophilic heterotrophs, the temperature growth profiles varied considerably among samples.Key words: psychrotrophs; Thiobacillus ferrooxidans; uranium mines.

The Effects of Acclimation Temperature on a Neuromuscular System of the Crayfish, Astacus Leptodactylus

1979 ◽  
Vol 78 (1) ◽  
pp. 281-293
Author(s):  
MIKKO HARRI ◽  
ERNST FLOREY
Keyword(s):  
Membrane Lipids ◽  
Characteristic Temperature ◽  
Resting Membrane Potential ◽  
Acclimation Temperature ◽  
Muscle Fibres ◽  
Astacus Leptodactylus ◽  
Tension Development ◽  
Temperature Range ◽  
Wide Range ◽  
Warm Acclimation

1. Crayfish, Astacus leptodactylus, were acclimated to 12 °C and to 25 °C. Nerve muscle preparations (closer muscle of walking legs) were subjected to temperatures ranging from 6 to 32 °C. 2. The resting membrane potential of muscle fibres was found to increase with temperature in a linear manner, but with a change in slope at around 170 in cold-acclimated preparations, and around 24 °C in warm-acclimated ones. 3. Temperature acclimation shifted the temperature range of maximal amplitudes of fast and slow e.j.p.s toward the acclimation temperature. Optimal facilitation of slow e.j.p.s also occurred near the respective acclimation temperature. 4. E.j.p. decay time is nearly independent of temperature in the upper temperature range but increases steeply when the temperature falls below a critical range around 17 °C in preparations from cold-acclimated animals, and around 22 °C after acclimation to 25 °C. 5. Peak depolarizations reached by summating facilitated e.j.p.s are conspicuously independent of temperature over a wide range (slow and fast e.j.p.s of cold-acclimated preparations, fast e.j.p.s of warm-acclimated ones) which extends to higher temperatures after warm acclimation in the case of fast e.j.p.s. In warm-acclimated preparations the peak depolarization of slow e.j.p.s first falls then rises and falls again as the temperature increases from 8 to 32 °C. 6. Tension development elicited by stimulation of the slow axon at a given frequency reaches maximal values at the lower end of the temperature range in cold-acclimated preparations. The maximum is shifted towards 20 °C after warm acclimation. Fast contractions decline with temperature; possible acclimation effects are masked by the great lability of fast contractions in warm-acclimated preparations. 7. It is suggested that changes in the composition of membrane lipids may be responsible for the effects of acclimation on the electrical parameters and their characteristic temperature dependence.

Broadening the valid temperature range of optical thermometry through dual-mode design

2018 ◽  
Vol 6 (41) ◽  
pp. 11178-11183 ◽  
Author(s):  
Yan Gao ◽  
Yao Cheng ◽  
Tao Hu ◽  
Zeliang Ji ◽  
Hang Lin ◽  
...  
Keyword(s):  
Dual Mode ◽  
Temperature Range ◽  
Mode Design ◽  
Optical Thermometry ◽  
Highly Sensitive ◽  
Wide Range ◽  
Optical Thermometer

This study highlights a highly sensitive dual-mode optical thermometer Pr3+:Gd2ZnTiO6 for thermal readings over a wide range of temperature.

Compositional variation in the chevkinite group: new data from igneous and metamorphic rocks

2009 ◽  
Vol 73 (5) ◽  
pp. 777-796 ◽  
Author(s):  
R. Macdonald ◽  
H. E. Belkin ◽  
F. Wall ◽  
B. Baginski
Keyword(s):  
Electron Microprobe ◽  
Host Rock ◽  
Metamorphic Rocks ◽  
Compositional Variation ◽  
Temperature Range ◽  
Wide Range ◽  
Host Rocks ◽  
Cation Sites ◽  
Dominant Cation

AbstractElectron microprobe analyses are presented of chevkinite-group minerals from Canada, USA, Guatemala, Norway, Scotland, Italy and India. The host rocks are metacarbonates, alkaline and subalkaline granitoids, quartz-bearing pegmatites, carbonatite and an inferred K-rich tuff. The analyses extend slightly the range of compositions in the chevkinite group, e.g. the most MgO-rich phases yet recorded, and we report two further examples where La is the dominant cation in the A site. Patchily- zoned crystals from Virginia and Guatemala contain both perrierite and chevkinite compositions. The new and published analyses are used to review compositional variation in minerals of the perrierite subgroup, which can form in a wide range of host rock compositions and over a substantial pressure- temperature range. The dominant substitutions in the various cation sites and a generalized substitution scheme are described.

Ignition Studies of C1-C7 Natural Gas Blends At Gas-Turbine Relevant Conditions

2021 ◽  
Author(s):  
Amrit Sahu ◽  
A.A.E.S Mohamed ◽  
Snehashish Panigrahy ◽  
Gilles Bourque ◽  
Henry Curran
Keyword(s):  
Natural Gas ◽  
Gas Turbine ◽  
Gas Mixtures ◽  
Rapid Compression Machine ◽  
Temperature Range ◽  
Auto Ignition ◽  
Wide Range ◽  
Model Predictions ◽  
Detailed Kinetic Model ◽  
Sensitization Effect

Abstract New ignition delay time measurements (IDT) of natural gas mixtures enriched with small amounts of n-hexane and n-heptane were performed in a rapid compression machine to interpret the sensitization effect of heavier hydrocarbons on auto-ignition at gas-turbine relevant conditions. The experimental data of natural gas mixtures containing alkanes from methane to n-heptane were carried out over a wide range of temperatures (840-1050 K), pressures (20-30 bar), and equivalence ratios (f = 0.5 and 1.5). The experiments were complemented with numerical simulations using a detailed kinetic model developed to investigate the effect of n-hexane and n-heptane additions. Model predictions show that the addition of even small amounts (1-2%) of n-hexane and n-heptane can lead to an increase in reactivity by ~40-60 ms at a temperature of 700 K. The IDTs of these mixtures decrease rapidly with an increase in the concentration of up to 7.5% but becomes almost independent of the C6/C7 concentration >10%. This sensitization effect of C6 and C7 is also found to be more pronounced in the temperature range 700-900 K compared to that at higher temperatures (>900 K). The reason is attributed to the dependence of IDT primarily on H2O2(+M)??H+?H (+M) at higher temperatures while the fuel-dependent reactions such as H-atom abstraction, RO2 dissociation, or Q OOH+O2 reactions are less important compared to the temperature range 700-900 K, where they are very important.

Development of liquidus thermobarometer for the simulation of equilibrium olivine-melt

2019 ◽  
pp. 62-74
Author(s):  
E. V. Koptev-Dvornikov ◽  
D. A. Bychkov
Keyword(s):  
Experimental Data ◽  
Liquidus Temperature ◽  
Small Error ◽  
Silicate Melt ◽  
System Of Equations ◽  
Temperature Range ◽  
Calculated Liquidus ◽  
Wide Range ◽  
Multidimensional Statistics

A system of equations of the liquidus thermobarometer of olivine — silicate melt was obtained by processing the sample of 772 experimental equilibria of olivines with basic melts using methods of multidimensional statistics. Equations reproduce with small error experimental data in a wide range of basite compositions (from komatiites to dacites), temperatures from 1040 to 1500 ᵒС, pressures from 1 bar up to 30 kbar. Thermobarometer testing demonstrated that the deviations of the calculated liquidus temperature from the experimental one in most of the temperature range do not exceed ±3 ᵒC.

Effects of water content and temperature on the surface conductivity of bentonite clay

Soil Research ◽  
2012 ◽  
Vol 50 (1) ◽  
pp. 44 ◽  
Author(s):  
M. A. Mojid ◽  
H. Cho
Keyword(s):  
Water Content ◽  
Bentonite Clay ◽  
Ionic Mobility ◽  
Surface Conductivity ◽  
Temperature Correction ◽  
Hydration Layer ◽  
Temperature Range ◽  
Wide Range ◽  
Hydration Layers ◽  
Water Contents

This study explored the effects of water content and temperature on the mobility of exchangeable cations (termed the surface ionic mobility and hereafter ionic mobility) in the hydration layers of bentonite clay. The ionic mobility directly governs the surface conductivity of the clay. The investigation was done by measuring the bulk electrical conductivity (EC) of four sand–bentonite mixtures of different proportions for a wide range of water contents under constant temperature, and three bentonite samples at different water contents over 5–90°C. The ionic mobility was determined from the surface conductivity at the mean ionic strength of the hydration layers. The ionic mobility in the sand–bentonite samples increased with an increase in hydration layer thickness. For a given thickness of the hydration layer, the greater the bentonite content of a sample, the smaller was the ionic mobility. The ionic mobility in the bentonite samples at different water contents also increased, at reduced rates, with a rise in temperature. Consequently, the surface conductivity of the samples increased non-uniformly, at two different rates, with an increase in temperature. The increasing rate of this conductivity depended on temperature; over the low temperature range which depended on the water content, the rate was 0.013 dS/m.K, and over higher temperature range, the rate decreased to 0.008 dS/m.K. The commonly used temperature correction factor, 0.019 dS/m.K, for EC therefore did not hold true for the bentonite samples.

The cracking of cyclo pentene on a silica-alumina catalyst

1960 ◽  
Vol 257 (1288) ◽  
pp. 132-145 ◽  
Keyword(s):  
Molecular Weight ◽  
Catalytic Cracking ◽  
Slow Step ◽  
Static System ◽  
Surface Complexes ◽  
Temperature Range ◽  
Carbonium Ions ◽  
Wide Range ◽  
Different Temperatures ◽  
Silica Alumina

The cracking of cyclo pentene on silica-alumina was studied in a flow system over the temperature range 368 to 505 °C. The analysis of the products was carried out by gas-liquid chromatographic techniques and the design of the apparatus made it possible to measure the pressures of compounds of low molecular weight at a series of points along the catalyst bed. Partial analyses were made of the extremely wide range of products of high molecular weight collected at the end of the reactor for reactions at three different temperatures. The results obtained were sufficiently detailed to provide activation energies for the for­mation of a number of the products and for the decomposition of cyclo pentene and to per­mit the application of thermodynamical calculations to ascertain the source of substances such as cyclo pentane and methyl cyclo pentane. The results of the flow experiments together with a subsidiary experiment on the reactions which occurred to cyclo pentene at 68 °C on the catalyst in a static system indicated that the formation, polymerization and isomerization of the surface complexes to condensed six-membered ring systems must be extremely rapid processes in the temperature range required for the catalytic cracking of cyclo pentene. These processes probably occur through the formation of carbonium ions and consequently the formation of these ions is unlikely to be the slow step in the catalytic cracking of olefins. The rate of the cracking reaction may depend on the rate of decomposition of carbonium ions considerably larger in size than the original olefin.

Interferons in the treatment of human cancer.

1984 ◽  
Vol 2 (4) ◽  
pp. 336-352 ◽  
Author(s):  
J M Kirkwood ◽  
M S Ernstoff
Keyword(s):  
Recombinant Dna ◽  
Human Cancer ◽  
Clinical Results ◽  
Common Species ◽  
Current Phase ◽  
Recombinant Dna Technology ◽  
Disease States ◽  
Wide Range

The interferons are the best known of biologic antineoplastic agents. Progress with the clinical application of interferons to cancer has been slow and complicated by the need for attention to a new spectrum of therapeutic and toxic effects manifest by the interferons. This summary of current phase I and II trial results with the interferons establishes their clinical potential. The maximally tolerated dosages of the most common species of interferon alpha produced in eukaryotic cells as well as by recombinant DNA technology in bacteria are now described in a variety of different disease states. "Naturally" produced eukaryotic as well as bacterially synthesized interferons have a similar, wide range of biologic effects in vitro and in vivo. Antiviral, antiproliferative, immunologic, and enzymologic functions of the interferons relevant to antineoplastic functions are under study. Knowledge of these mechanisms should improve the clinical results obtained in human cancer. Species and subspecies differences in the activity of interferons may lead to selective use of the pure interferon subspecies, alone or in combination. The use of the interferons and other antineoplastic biologics, such as antibody or chemotherapy, are subsequent goals that are now on the horizon.

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