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211.
Fatty Acid and Isoprenoid Quinone Composition in the classification of Bacteroides melaninogenicus and Related Taxa 总被引:5,自引:4,他引:1
Aerobic deterioration of lucerne, maize and wheat silages was characterized by rapid increases in yeast and mould flora which oxidized lactic and volatile acids resulting in increased temperature and pH. While populations of yeasts and moulds were similar, temperature increases were slightly greater for silages inoculated with Lactobacillus acidophilus and Candida spp. After 48 h the pH of the inoculated silages was higher in general and concentrations of acids were lower than controls. Bacterial growth was slight although continued lactic acid production was probable. In contrast to lucerne and maize silages, the pH of wheat silage remained stable during this period because of high butyric levels, but temperature and yeast populations increased. After 48 h the pH rose above 5 in maize and lucerne, and bacterial growth and metabolic activity resumed resulting in volatile and non-volatile acid production from carbohydrate fermentation and deamination of amino acids. During this phase of aerobic deterioration yeast growth slowed or stopped, but temperatures remained high and pH continued to climb probably because of production of ammonia. The changes in gross composition of the silages did not follow any particular pattern. Losses in dry matter were small (2.5–4.0%) and changes in individual components probably reflect this loss rather than substantial changes. Protein availability in the lucerne silages undoubtedly decreased, as protein losses were high. It is concluded that the aerobic deterioration of silage is enhanced by the addition of L. acidophilus and Candida spp. at ensiling. 相似文献
212.
213.
SYNOPSIS. Some neutral carbonyl compounds synthesized by Cryptomonas, ovata var. palustris were identified as methanal, ethanal, 2-propanone, pentanal, and heptanal by means of thin-layer chromatography, gas chromatography and infrared spectroscopy. 相似文献
214.
N. M. COLLINS 《Ecological Entomology》1979,4(3):231-238
Abstract. 1. A single nest of the black surface-foraging nasute termite Hospitalitermes umbrinus was studied for 5 days in July 1978. Foraging parties of workers and soldiers tend to leave the nest in a continuous stream in the evening and return carrying food balls during the following morning.
2. An estimated maximum of 500000 individuals were involved in the foraging excursions. At a density of 3 nests ha-1 , the total foraging population is estimated as being at least 180 m-2 .
3. The colony brought back an estimated 46.4 g (d.w.) of food in 4 days. The biomass of the colony was estimated at 349 g (d.w.) ( c. 1396 g w.w.) excluding alates and the consumption at 8.3 mg (d.w.) g-1 (w.w.) d-1 .
4. The food balls were found to be of two types, light and dark coloured. The light balls contained wood constituents, bryophytes, blue-green algae and fungal hyphae while the dark balls consisted mainly of lichens and their spores.
5. Swarming began at 14.30 hours on 9 July and ended with the nuptial flight at 17.32 hours. About 3000 alates were released. They climbed to 9 m on a tree before taking off. 相似文献
2. An estimated maximum of 500000 individuals were involved in the foraging excursions. At a density of 3 nests ha
3. The colony brought back an estimated 46.4 g (d.w.) of food in 4 days. The biomass of the colony was estimated at 349 g (d.w.) ( c. 1396 g w.w.) excluding alates and the consumption at 8.3 mg (d.w.) g
4. The food balls were found to be of two types, light and dark coloured. The light balls contained wood constituents, bryophytes, blue-green algae and fungal hyphae while the dark balls consisted mainly of lichens and their spores.
5. Swarming began at 14.30 hours on 9 July and ended with the nuptial flight at 17.32 hours. About 3000 alates were released. They climbed to 9 m on a tree before taking off. 相似文献
215.
Pharmacologic differentiation between epinephrine- and HGF-hyperglycemias: application in analysis of cobalt-hyperglycemia 总被引:3,自引:0,他引:3
216.
217.
Assay of plasma antihemophilic activity in normal heterozygous (hemophilia) and prothrombinopenic dogs 总被引:5,自引:0,他引:5
218.