Physical management and interpretation of an environmentally controlled composting ecosystem

1992 ◽  
Vol 32 (5) ◽  
pp. 657 ◽  
Author(s):  
E Harper ◽  
FC Miller ◽  
BJ Macauley
Keyword(s):  
Feedback Control ◽  
Mass Balance ◽  
Heat Production ◽  
Dry Matter ◽  
Heat Evolution ◽  
Processing Conditions ◽  
Mushroom Cultivation ◽  
Maximum Heat ◽  
Temperature Feedback ◽  
Wet Weight

Compost for mushroom cultivation was prepared in an environmentally controlled composting(ECC) system of 10 t maximum loading. Early in processing, ventilation was manually controlled to provide aerobic conditions. When the desired compost temperatures were reached, control through temperature feedback was used. Physical uniformity of processing conditions was achieved by recirculating large volumes of air within the reactor. Heat production was found to peak early in the composting process, reaching a maximum of about 8-9 W/kg initial wet (67-71%) substrate. When compost temperatures were allowed to rise to 63�C, maximum heat production occurred at 55-63�C. Total heat production per initial wet weight averaged 1.23 MJ/kg (range 0.92-1.51 MJ/kg), or 5.11 MJ/kg (range 4.04-7.57 MJ/kg) when measured per initial volatile dry matter. Heat evolution averaged 18.3 MJ/kg decomposed (range 15.4-22.0 MJ/kg). Oxygen usage followed a pattern similar to that of heat production reaching a maximum in the 55-63�C range. Peak O2 usage was about 9 x 10-7 kg O2/kg composts, or in volume terms, 2.9 x 10-6 m3 Air/kg comp0st.s. During temperature feedback control, O2 levels were maintained at about 19%. The enclosed ECC system permitted mass balance data to be collected for various components. Trials demonstrated that temperature and O2 could be closely controlled, resulting in-good compost uniformity.

The Relation of Oxygen Consumption to Body Size and to Temperature in the Larvae of Chironomus Riparius Meigen

1958 ◽  
Vol 35 (2) ◽  
pp. 383-395
Author(s):  
R. W. EDWARDS
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Dry Matter ◽  
Larval Instar ◽  
Weight Ratio ◽  
Dry Weight ◽  
Chironomus Riparius ◽  
Consumption Rates ◽  
Rate Of Oxygen Consumption ◽  
Wet Weight

1. The oxygen consumption rates of 3rd- and 4th-instar larvae of Chironomus riparius have been measured at 10 and 20° C. using a constant-volume respirometer. 2. The oxygen consumption is approximately proportional to the 0.7 power of the dry weight: it is not proportional to the estimated surface area. 3. This relationship between oxygen consumption and dry weight is the same at 10 and at 20° C.. 4. The rate of oxygen consumption at 20° C. is greater than at 10° C. by a factor of 2.6. 5. During growth the percentage of dry matter of 4th-instar larvae increases from 10 to 16 and the specific gravity from 1.030 to 1.043. 6. The change in the dry weight/wet weight ratio during the 4 larval instar supports the theory of heterauxesis. 7. At 20° C., ‘summer’ larvae respire faster than ‘winter’ larvae.

THE EFFECT OF INGESTED CHLORTETRACYCLINE ON SOME HYDROLASES AND ORGANS ASSOCIATED WITH THE DIGESTIVE PROCESS IN GROWING PIGS: II. PROTEASE, AMYLASE, AND GELLULASE ACTIVITY OF THE CONTENTS OF THE SMALL INTESTINE AND OF THE CECUM; WEIGHTS OF SMALL INTESTINE AND MUCOSA

1957 ◽  
Vol 35 (3) ◽  
pp. 195-202 ◽  
Author(s):  
M. A. A. Vonk ◽  
L. W. McElroy ◽  
R. T. Berg
Keyword(s):  
Small Intestine ◽  
Dry Matter ◽  
Cellulase Activity ◽  
Dry Weight ◽  
Growing Pigs ◽  
Weanling Pigs ◽  
Intestinal Contents ◽  
Wet Weight ◽  
The Mean ◽  
Ad Libitum

Four treatments, involving differences in method of feeding and interval between last feed and slaughter, were employed in a study of the effect of dietary chlortetracycline on protease, amylase, and cellulase activity in the intestinal and cecal contents of 16 pairs of weanling pigs. Most consistent results were obtained with six pairs which were limited pair-fed except for the final feeding during which feed was available ad libitum for a 4-hour period ending 18 hours before slaughter. The mean total activities of all three hydrolases in the contents of the small intestines and of the ceca of the antibiotic-fed animals of these six pairs were significantly greater than in those of the control animals. Expressed as activity per gram dry matter of intestinal contents, significantly higher values for protease and amylase, but not for cellulase, were observed in the pigs that had received chlortetracycline. When the combined results obtained from all 16 pairs of the experimental animals were analyzed, the results showed that on a basis of activity per gram dry matter of intestinal contents, ingested chlortetracycline was associated with significant increases in amylase and cellulase but not in protease activity. Protease, amylase, and cellulase activities per gram dry matter of cecal contents were higher for pigs fed the antibiotic than for their controls. The mean wet weight of the empty small intestine and the mean dry weight of the mucosa scraped from the anterior 3-meter section of the small intestine were lower for the chlortetracycline-fed animals, but the differences were not statistically significant.

THERMOGENESIS DUE TO EXERCISE AND COLD IN WARM- AND COLD-ACCLIMATED RATS

1963 ◽  
Vol 41 (1) ◽  
pp. 629-634 ◽  
Author(s):  
J. S. Hart ◽  
L. Jansky
Keyword(s):  
Cold Acclimation ◽  
Heat Production ◽  
Nonshivering Thermogenesis ◽  
Maximum Heat ◽  
Temperature Range ◽  
Sustained Effort ◽  
Extreme Cold

In both warm- and cold-acclimated rats, heat production was measured while the animals were at rest and running at maximum sustained effort at temperatures from 30 °C to those giving maximum thermogenesis. In both these groups, the maximum heat production during exercise did not exceed the maximum at rest in extreme cold. Exercise substituted for shivering in warm-acclimated rats and, at temperatures below 10 °C, resulted in hypothermia. Heat derived from exercise added to nonshivering thermogenesis in cold-acclimated rats above −20 °C. Below −20 °C, exercise substituted for shivering as in warm-acclimated rats at higher temperatures, and the rats became hypothermic. Extension of the temperature range for activity by cold acclimation appears to result from development of nonshivering thermogenesis, which, unlike shivering, is not eliminated by exercise.

Effect of fibre supplementation on dag formation and flystrike in sheep grazing spring pastures

2006 ◽  
Vol 46 (7) ◽  
pp. 783 ◽  
Author(s):  
B. S. Davidson ◽  
S. J. Chaplin ◽  
C. Laird
Keyword(s):  
Dry Matter ◽  
Crossover Trial ◽  
Control Group ◽  
Sheep Grazing ◽  
Treatment Groups ◽  
Fecal Egg Count ◽  
Fibre Treatment ◽  
Wet Weight ◽  
Ad Libitum ◽  
Low Levels

Sheep on spring pastures may scour excessively due to the low levels of neutral detergent fibre. Scouring leads to dag formation, which predisposes sheep to flystrike, particularly in the breech area, posing a considerable challenge to sheep producers. This trial was undertaken to test whether supplementing sheep on spring pasture with fibre would reduce diarrhoea and thereby reduce dag formation and flystrike. Four hundred first-lambing Merino ewes were randomly allocated to control (no fibre supplementation) and fibre treatment (ad libitum cereal hay or wheat straw supplementation) groups in a 2-paddock crossover trial, which was conducted from August through the spring flush to crutching in October. The bulk fecal egg counts of each group were no different at the start of the trial but the fibre group had a higher (P<0.05) fecal egg count than the control at crutching. Fecal egg count was not correlated with dag score. Fecal dry matter percentage was higher (P<0.05) in the fibre group but there was no difference in dag wet weight or dry matter percentage between the treatment groups. Dag scores of a sample of 100 sheep from each group were significantly (P<0.01) lower at crutching. There was no difference between the groups in the incidence of flystrike, however, there were significantly (P<0.001) more sheep with high dag scores (>3) in the control group than the fibre treatment group. These results indicate that the supplementation of spring pasture with low quality hay or straw can reduce dag formation by improving the consistency of feces and, thereby, reduce the number of sheep with dag scores greater than 3.

The effect of method of conservation of grass and supplementation on energy and nitrogen utilization by lambs

1999 ◽  
Vol 133 (4) ◽  
pp. 409-417
Author(s):  
D. E. KIRKPATRICK ◽  
R. W. J. STEEN
Keyword(s):  
Energy Intake ◽  
Heat Production ◽  
Dry Matter ◽  
Agricultural Research ◽  
Nitrogen Retention ◽  
Linear Increase ◽  
Nitrogen Utilization ◽  
Metabolizable Energy ◽  
Agricultural Research Council ◽  
Energy Retention

An experiment was carried out in 1994 to examine energy and nitrogen utilization of lambs offered two contrasting grass-based diets. The two forages, which were from the same parent herbage, were grass silage and grass which was conserved by freezing. They were offered as sole diets or supplemented with either 250 or 500 g concentrates per kg total dry matter intake (DMI) to give a total of six experimental treatments. Seventy-two Dutch Texel × Greyface (Border Leicester × Blackface) lambs, consisting of 36 males which were initially 36 (S.D. 4·9) kg liveweight and 36 females which were initially 34 (S.D. 2·5) kg liveweight were used. Ensiling significantly increased apparent digestibility of dry matter, energy and nitrogen (P<0·001), but had no significant effect on methane energy loss as a proportion of gross energy intake, metabolizable energy intake (MEI), heat production, energy retained, efficiency of utilization of energy for growth (kg) or nitrogen retention. Supplementation of forage with concentrates resulted in a curvilinear decrease in heat production expressed as a proportion of MEI (P<0·05) and a linear increase in energy retention, expressed as an absolute value or as a proportion of MEI (P<0·05). Supplementation of forage tended to increase kg when calculated using Agricultural Research Council estimates of maintenance energy requirements, but had no significant effect when alternative estimates of maintenance were used. It is concluded that ensiling had no effect on efficiency of utilization of energy or nitrogen as measured by indirect calorimetry.

Energy metabolism of oiled muskrats

1974 ◽  
Vol 52 (8) ◽  
pp. 1057-1062 ◽  
Author(s):  
E. H. McEwan ◽  
N. Aitchison ◽  
P. E. Whitehead
Keyword(s):  
Thermal Conductivity ◽  
Energy Metabolism ◽  
Heat Production ◽  
Thermal Conduction ◽  
Dry Matter ◽  
Fold Increase ◽  
Dry Matter Intake ◽  
Natural Conditions ◽  
Ambient Temperatures ◽  
Feeding Activities

The heat production of muskrats (Ondatra zibethica), oiled with varying quantities of crude oil, was measured at three ambient temperatures, −5, 5, and 10C on days 0, 1, and 3 after oiling. On day 0, the heat production of muskrats oiled with 1.9 to 42.3 g of oil was from 14 to 119% higher, respectively, than the non-oiled muskrats. Three days after oiling, the metabolic rate of oiled muskrats was about the same as the control values. A similar trend was determined for ambient temperatures of 5 and 10C. Heavy oiling increased the thermal conduction of muskrats by as much as 122%. To compensate for the loss of insulation and increased thermal conductivity of the fur, there was a 2.5-fold increase in dry-matter intake. In view of their dependence on water, both for feeding activities and a place for refuge, it is doubtful if muskrats exposed to moderate quantities of oil could survive under natural conditions.

The fat-free dry matter of epididymal adipose tissue in relation to metabolic activity

1968 ◽  
Vol 46 (6) ◽  
pp. 914-917
Author(s):  
Luc Trahan ◽  
Edouard Pagé
Keyword(s):  
Adipose Tissue ◽  
Metabolic Activity ◽  
Dry Matter ◽  
Matter Content ◽  
Weight Basis ◽  
Epididymal Adipose Tissue ◽  
Dry Matter Content ◽  
Fat Pad ◽  
Wet Weight ◽  
The Right

In rats exposed to cold over a 5-week period there occurs a rise and then a partial return to initial values of the fat-free dry matter content of epididymal adipose tissue. The fat-free dry matter is also slightly higher in the right fat pad. Under such circumstances there may be some advantage in expressing metabolic activity in terms of fat-free dry matter rather than on a wet weight basis. Both methods are equally satisfactory in control rats.

Temperature feedback control for long-term carrier-envelope phase locking

2009 ◽  
Vol 48 (27) ◽  
pp. 5127 ◽  
Author(s):  
Chenxia Yun ◽  
Shouyuan Chen ◽  
He Wang ◽  
Michael Chini ◽  
Zenghu Chang
Keyword(s):  
Feedback Control ◽  
Phase Locking ◽  
Carrier Envelope Phase ◽  
Temperature Feedback

scholarly journals Development of frozen-fried yam slices: optimization of the processing conditions

2012 ◽  
Vol 12 (55) ◽  
pp. 7055-7071
Author(s):  
Y Touré ◽  
◽  
C Nindjin ◽  
Y Brostaux ◽  
GN Amani ◽  
...  
Keyword(s):  
Dry Matter ◽  
Industrial Process ◽  
Quality Parameters ◽  
French Fries ◽  
Added Value ◽  
Processing Conditions ◽  
Oil Uptake ◽  
Frying Temperature ◽  
Frying Time ◽  
Dioscorea Cayenensis

The research performed on yam processing mainly concerns the production of crisps and flour. However, its transformation into deep-frozen French fries does not necessitate any other equipment than those used for potatoes. The industrial process of production of frozen French fries traditionally includes a pre-frying step. These steps contribute to the development of color and crispness, and the oil partially absorbed inhibits dehydration during the freezing step. The aim of this study was to optimize frying conditions of deep-frozen fried yam (Dioscorea cayenensis varKponan) slices. The effect of pre-frying time and temperature, final frying time and temperature on the oil uptake, texture, dry matter and colour of the fried yam slices has been studied. Frying conditions optimized with Box-Behnken experimental design were short pre-frying and frying conditions at high temperature characterized by prefrying temperature at 157-170°C during 5-9s and frying temperature at 181-188°C for 2min 15s-2min 30s; or long pre-frying and frying conditions at low temperature characterized by pre-frying temperature at 150-158°C during 10-15s and frying temperature 170-177°C for 3-3min 15s. An adiabatic system was also developed by means of an insulator in which the core temperature of fried yam slices can be maintained constant at about 55°C after 15min of cooling, facilitating texture measurements at constant temperature. The present results may help in choosing the yam slices frying condition to be applied in order to achieve the desirable fried yam slices quality, required for protection against certain diseases like obesity. These models may also provide guidance as to how to control these quality parameters by altering four key environmental factors, pre-frying temperature and time and, final frying temperature and time. This process can also be commercialized and does not necessitate any other cost for equipment than those used for potatoes French fries and might be an interesting way of added value processing for this highly perishable yam tuber.

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