61. Effect of temperature, pressure, gas-composition, particle size and the nature of carbon on the rate of oxidation of carbons in CO2-CO gas mixtures

Carbon ◽  
1969 ◽  
Vol 7 (6) ◽  
pp. 718
Author(s):  
E.T Turkdogan
Keyword(s):  
Particle Size ◽  
Gas Mixtures ◽  
Effect Of Temperature ◽  
Gas Composition ◽  
Co Gas

scholarly journals Metabolic engineering of Moorella thermoacetica for thermophilic bioconversion of gaseous substrates to a volatile chemical

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Junya Kato ◽  
Kaisei Takemura ◽  
Setsu Kato ◽  
Tatsuya Fujii ◽  
Keisuke Wada ◽  
...  
Keyword(s):  
Carbon Flux ◽  
Cost Effective ◽  
Gas Composition ◽  
Autotrophic Growth ◽  
Acetyl Coenzyme A ◽  
Volatile Chemicals ◽  
Moorella Thermoacetica ◽  
Gas Fermentation ◽  
Dry Cell ◽  
Co Gas

AbstractGas fermentation is one of the promising bioprocesses to convert CO2 or syngas to important chemicals. Thermophilic gas fermentation of volatile chemicals has the potential for the development of consolidated bioprocesses that can simultaneously separate products during fermentation. This study reports the production of acetone from CO2 and H2, CO, or syngas by introducing the acetone production pathway using acetyl–coenzyme A (Ac-CoA) and acetate produced via the Wood–Ljungdahl pathway in Moorella thermoacetica. Reducing the carbon flux from Ac-CoA to acetate through genetic engineering successfully enhanced acetone productivity, which varied on the basis of the gas composition. The highest acetone productivity was obtained with CO–H2, while autotrophic growth collapsed with CO2–H2. By adding H2 to CO, the acetone productivity from the same amount of carbon source increased compared to CO gas only, and the maximum specific acetone production rate also increased from 0.04 to 0.09 g-acetone/g-dry cell/h. Our development of the engineered thermophilic acetogen M. thermoacetica, which grows at a temperature higher than the boiling point of acetone (58 °C), would pave the way for developing a consolidated process with simplified and cost-effective recovery via condensation following gas fermentation.

EFFECT OF TEMPERATURE AND GAS COMPOSITION ON QUALITY OF GARLIC BULBS

2007 ◽  
pp. 77-82 ◽  
Author(s):  
D. Nei ◽  
N. Nakamura ◽  
H. Umehara ◽  
P. Roy ◽  
H. Okadome ◽  
...  
Keyword(s):  
Effect Of Temperature ◽  
Gas Composition

scholarly journals Validation of spectroscopic gas analyzer accuracy using gravimetric standard gas mixtures: Impact of background gas composition on CO<sub>2</sub> quantitation by cavity ring-down spectroscopy

2017 ◽  
Author(s):  
Jeong Sik Lim ◽  
Miyeon Park ◽  
Jinbok Lee ◽  
Jeongsoon Lee
Keyword(s):  
Ambient Air ◽  
Gas Mixtures ◽  
Gas Composition ◽  
Optical Intensity ◽  
Negative Deviation ◽  
Gas Analyzer ◽  
Pressure Broadening ◽  
Background Gas ◽  
Standard Gas Mixtures ◽  
Cavity Ring Down

Abstract. Effect of background gas composition on the measurement of CO2 levels was investigated by wavelength-scanned cavity ring-down spectrometry (WS-CRDS) employing a spectral line centered at the R(1) of the (3 0° 1)III ← (0 0 0) band. For this purpose, eight cylinders with various gas compositions were gravimetrically and manometrically prepared within 2σ = 0.1 %, and these gas mixtures were introduced into the WS-CRDS analyzer calibrated against standards of ambient air composition. Depending on the gas composition, deviations between CRDS-determined and gravimetrically (or manometrically) assigned CO2 concentrations ranged from −9.77 to 5.36 μmol/mol, e.g., excess N2 exhibited a negative deviation, whereas excess Ar showed a positive one. The total pressure broadening coefficients (TBPCs) obtained from the composition of N2, O2 and Ar thoroughly corrected the deviations up to −0.5–0.6 μmol/mol, while these values were −0.43–1.43 μmol/mol considering PBCs induced by only N2. The use of TBPCs enhanced deviations to be corrected to ~ 0.15 %. Furthermore, the above correction linearly shifted CRDS responses for a wide extent of TPBCs ranging from 0.065 to 0.081 cm−1 atm−1. Thus, accurate measurements using optical intensity-based techniques such as WS-CRDS require TBPC-based instrument calibration.

scholarly journals The Effect of Temperature, Dietary Energy Level, and Corn Particle Size on Broiler Performance

1992 ◽  
Vol 71 (4) ◽  
pp. 618-624 ◽  
Author(s):  
B.D. LOTT ◽  
E.J. DAY ◽  
J.W. DEATON ◽  
J.D. MAY
Keyword(s):  
Particle Size ◽  
Energy Level ◽  
Effect Of Temperature ◽  
Dietary Energy ◽  
Broiler Performance ◽  
Corn Particle Size

Methods of Improving Glow-Discharge-Deposited a-Si1−xGex:H

1991 ◽  
Vol 219 ◽  
Author(s):  
Y. S. Tsuo ◽  
Y. Xu ◽  
E. A. Ramsay ◽  
R. S. Crandall ◽  
S. J. Salomon ◽  
...  
Keyword(s):  
Material Processing ◽  
Glow Discharge ◽  
Substrate Temperature ◽  
Gas Mixtures ◽  
Gas Composition ◽  
Processing Methods ◽  
Helium 4 ◽  
Process Gas

ABSTRACTWe have studied methods of improving glow-discharge-deposited a-Si1−x Gex :H alloys deposited using silane and germane gas mixtures. Material processing methods studied include (1) varying the substrate temperature from 170° to 280°C, (2) varying the process gas composition and pressure, (3) dilution of the feed gas by hydrogen, argon, or helium, (4) enhancing etching during deposition by adding small amounts of XeF2 vapor into the process gas, and (5) postdeposition annealing and/or hydrogenation.

Effect of temperature on central chemical control of ventilation in the alligator Alligator mississippiensis

1993 ◽  
Vol 179 (1) ◽  
pp. 261-272
Author(s):  
L. G. Branco ◽  
S. C. Wood
Keyword(s):  
Fourth Ventricle ◽  
Ventilatory Response ◽  
Pulmonary Ventilation ◽  
Gas Mixtures ◽  
Alligator Mississippiensis ◽  
Effect Of Temperature ◽  
Peripheral Chemoreceptor ◽  
Peripheral Chemoreceptors ◽  
Ph Values ◽  
Arterial Ph

Central chemoreceptor function was assessed in unanesthetized alligators, Alligator mississippiensis, at body temperatures of 15, 25 and 35 degrees C. Two experiments were performed. In the first experiment, the fourth ventricle was perfused with mock cerebrospinal fluid (CSF) solutions of different pH values (7.1-7.9). Changes in pulmonary ventilation were evaluated with a pneumotachograph and arterial pH (pHa) was measured. Perfusion with low-pH solutions increased ventilation and arterial pH. Perfusion with high-pH solutions decreased ventilation and arterial pH. Mock CSF pH had a greater effect at higher temperatures. In the second experiment, the relative contributions of central and peripheral chemoreceptor drive to breathing were evaluated using hypercapnic gas mixtures to stimulate both central and peripheral chemoreceptors. Hypercapnia caused an increase in ventilation which was larger at higher temperatures. To stimulate only the peripheral chemoreceptors, the same hypercapnic gas mixtures were applied while the CSF pH of the fourth ventricle was kept constant by perfusion with a mock CSF solution. This reduced significantly the ventilatory response induced by hypercapnia. These data indicate that, regardless of the temperature, central chemoreceptors play a major role in the ventilatory regulation of the alligator. The change in pHa with temperature is compatible with the alphastat hypothesis.

Separation of hydrogen from H2CO gas mixtures using amorphous CaNi alloy films

1991 ◽  
Vol 171 (2) ◽  
pp. 353-356 ◽  
Author(s):  
H. Sakaguchi ◽  
E. Yamamoto ◽  
G. Adachi
Keyword(s):  
Gas Mixtures ◽  
Alloy Films ◽  
Ni Alloy ◽  
Co Gas

The Effect of Hydrothermal Dewatering Temperature on Hydro-Char Obtained from Oily Scum

2019 ◽  
Vol 971 ◽  
pp. 127-133
Author(s):  
Shuang Hui Deng ◽  
Xue Bin Wang ◽  
Dao Yang Ma ◽  
Xu Chao Lu ◽  
Hou Zhang Tan
Keyword(s):  
Particle Size ◽  
Moisture Content ◽  
Surface Characteristics ◽  
Gas Content ◽  
Effect Of Temperature ◽  
Content Increase ◽  
Liquid Content ◽  
Physico Chemical ◽  
Methylene Groups ◽  
Reactor Temperature

Oily scum was treated by hydrothermal dewatering (HTD) under 120-240°C. The changes of surface characteristics and physico-chemical structure of oily scum were investigated and the effect of temperature on the properties of the hydro-char obtained from oily scum was analyzed through different characterization techniques. Results show that the moisture content of HTD treated hydro-char decreases as the temperature increases, which implies that the oily scum can be dewatered and upgraded through HTD method. The morphologies of the HTD pretreated oily scum present less oil content, smaller particle size, and become darker. As the reactor temperature increases from 120 to 240°C during the HTD process, the moisture content of hydro-char obtained decreases from 35.51 to 11.31%, while the liquid content and hydro-char content increase from 58.53 to 79.76% and from 2.50 to 5.29%, respectively, and the released gas content slightly varies in the range of 3.14 - 4.31%. The breaking and gathering effects of the HTD upgrading on oily scum result in a wide particle size distribution of products, which indicates that the overall structure of raw oily scum has been destroyed. With the increase of HTD temperature, the shorten vibration of methylene groups in hydro-char products is weakened.

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