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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Moisture conditions in the savanna region of West Africa.

Swami, Kala, 1944- January 1970 (has links)
No description available.
322

Identification of Soil Moisture Deficits Influencing Genotype-by-Environment Interactions In Maize (ZEA MAYS L.)

Hooyer, Mathew 27 November 2012 (has links)
Maize grain yield is often highly influenced by the genotype-by-environment (GxE) interactions which limit plant breeders’ ability to select for superior performance as variation in line performance exists across different environments. While studies have focused on the genetic components underlining GxE interactions, few have investigated the environmental components. The focus of this thesis was to investigate the role that soil moisture stress plays in the formation of GxE patterns using a unique set of hybrid recombinant inbred lines (RIL) that exhibit minimal phenological differences. With the use of environmental groups (EG, environments with similar GxE patterns), the field trials demonstrated that different EGs form when relative soil moisture stress is moderate to high; however, relative low soil moisture stress did not appear to influence the formation of GxE patterns. Seasonal corn heat unit (CHU) accumulation among EGs was the likely cause for EG differentiation among the low moisture stress EGs. It appears that CHUs were the primary cause of different GxE patterns forming when they did not exceed the recommended CHU for a population and when CHU differed greatly from one environment to another. When CHU were not limiting different GxE patterns formed based on the relatively moderate to high soil moisture stress conditions within the growing season. / Ontario Research Fund, National Science and Engineering Research Council, and The Ontario Ministry of Agriculture, Food and Rural Affairs.
323

Torrefaction and Pelletization of Different Forms of Biomass of Ontario

Acharya, Bimal 02 May 2013 (has links)
The purpose of this study is to investigate the torrefaction and pelletization behavior, hydrophobicity, storage behavior, ash analysis on three different biomasses: one (willow pellets) from wood products, one (oat pellets) from agricultural products and one (poultry litter) from the non-lignocellulosic biomass products during the processes. Four different torrefaction temperatures from 200°C-300°C, at 10-60 minute residence times, 0%-2.4% oxygen concentration, were considered. Of these, 285°C for willow pellets, 270°C for oat pellets and 275°C for poultry litter were found to be optimum for hydrophobicity. Studies of XRD and SEM of biomass ash at 800°C, 900°C and 1000°C were also carried out. The aforementioned results indicate that torrefaction is a feasible alternative to improve energy properties of ordinary biomass and prevent moisture re-absorption during storage.
324

Physicochemical Transformations in Low-Moisture Dough During Baking

Walker, Shane Bruce 09 May 2013 (has links)
Transformations in the properties of low-moisture dough products (cookies and crackers) during baking have been studied under idealized conditions in pilot facilities and laboratories. However, little research is published that describes dough development within the context of complex industrial baking processes. A process mapping approach was adopted, in which oven parameters were profiled and matched against changes in dough. In cookies, changes to starch A-granules, including loss of granule birefringence, disruption to granule borders and increased gel viscosity were observed. Development of acrylamide in cookies was seen to trail colour development, suggesting options for mediating acrylamide content. In crackers, the presence of additional water allowed significant changes to starch A-granules to occur, including: swelling similar to the early stages of gelatinization in bread, reduced pasting ability, a drop in enthalpy, and a loss of crystallinity. Emulation of low-moisture dough baking at the benchtop level, based upon internal product temperature data from industrial processes, was found to be limited in its ability to produce crackers having appropriate leavening and internal structure development. The determination of isosteric heat of desorption values for cookies and crackers, modeled on industrial processes at temperatures > 100°C, gave values of 44.3 and 42.7 kJ/mol, respectively. This data will be useful for establishing energy requirements in industrial baking processes / MITACS, OMAFRA
325

Some effects of relative humidity on the porous structure of paper

Gurnagul, N. (Norayr) January 1985 (has links)
No description available.
326

Soil water balance of intercropped corn under water table management

Qureshi, Suhail Ahmad January 1995 (has links)
A one year water table management field study was conducted on a Soulanges sandy loam soil in Soulanges county, Quebec. Two controlled water table levels, i.e. 0.5 m and 0.75 m from the soil surface, as well as free outlet conventional drainage treatments were established in monocropped corn (Zea mays L.) and corn intercropped with ryegrass (Lolium multiflorum Lam) plots. / Cropping system showed no significant effects on evapotranspiration, and on soil moisture distribution. It was observed that the 0.5 m and 0.75 m controlled water tables (CWT) provided the same soil moisture trends in both cropping systems. The soil moisture was always higher in controlled water table plots compared to freely drained plots. The water use efficiency of 0.75 m CWT in both cropping systems was high compared to 0.5 m CWT. / The soil moisture contents at three depths were only 2% to 10% less in intercropped plots compared to monocropped plots. The soil moisture was 12 to 13% higher in CWT plots compared to freely drained plots for both cropping systems. The soil moisture in 0.5 m CWT and 0.75 m CWT plots was not significantly different. The average water table levels in monocropped plots were not significantly different from intercropped plots.
327

Les tensiometres pour l'irrigation en milieu tourbeaux

Lebeau, Benoit January 1995 (has links)
Water management for the irrigation of containerized production remains a task reserved to a highly qualified personnel. Without proper instruments to determine the actual water needs, nursery crops can face growth losses of 20 to 30%. / Reviewing the different methods that are used in field production, tensiometer have shown the greatest potential of adaptation to potted plants. / Tests on the utilization of tensiometer were realized on two peat-vermiculite substrates, using two types of porous cup (1 bat--standard flow and 1 bar--high flow). The instruments were tested while permanently fixed in the growing medium, and temporarily fixed for three hours in the growing medium. / The results show that the instruments give excellent measurements for normal condition of growth, requiring saturation level between 50 and 100%, and that for both mode of operation. / Preferably, the choice of the instrument should be based on the hydraulic characteristics of the substrate. Little difference has been found using both instrument in the substrate 1, but in substrate 2 however, the high flow porous cups have given better response. The high flow cups have higher porosity and bigger pores that suit better substrate 2, which is made of coarser particles.
328

The effect of moisture on the interfacial fracture toughness of packaging interfaces

Ferguson, Timothy Patrick 12 1900 (has links)
No description available.
329

The use of gamma radiation to measure moisture distribution during drying processes

Hatcher, John Douglas 12 1900 (has links)
No description available.
330

Transient measurement techniques for the thermogradient coefficient and the thermal conductivity of moist soils

Gibson, Edward Bryan 05 1900 (has links)
No description available.

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