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991.
992.
A solid electrolyte fuel cell operating on ammonia fuel has been constructed and tested. The yield of nitric oxide can exceed 60 percent with simultaneous electric energy production. Two dimensionless numbers have been identified which govern the product selectivity and power output of this fuel cell. The cell appears to be a promising candidate for nitric acid and electric energy cogeneration.  相似文献   
993.
Two compounds with highly potent juvenile hormone activity were isolated and identified from the oil of sweet basil, Ocimum basilicum L., Labiatae.  相似文献   
994.
It is proposed that human comfort could be provided in otherwise chilly surroundings by filling the occupied space with electromagnetic energy of centimeter wavelength. Very considerable reductions in the consumption of energy required for the heating of buildings should result from the lowering of interior temperatures thereby permitted.  相似文献   
995.
996.
997.
1. A caliper technique for estimating the amount of abdominal fat in live broilers is described.

2. Sixty‐three male and 47 female broilers sampled at 63 d of age from an unselected control line were used to examine the accuracy of the caliper measure in predicting abdominal fat.

3. Phenotypic correlations between caliper measure and the proportion of abdominal fat were + 0.80, +0.79 and +0.81 in males, females and the heaviest 20% of males respectively.

4. The application of the technique as an indirect means of selecting for decreased abdominal fat in commercial broiler breeding programmes is discussed.  相似文献   

998.
1. In a series of experiments with laying hens, attempts were made to eliminate the anti‐nutritive factor which reduces egg production when feeding field beans (Vicia faba L.) as a source of supplementary protein in cereal‐based diets.

2. Neither pelleting diets nor heat processing the beans by autoclaving proved beneficial. A continuous‐flow process for infra‐red heating of the seeds at 150 °C for 70 s followed immediately by flaking (micronisation) gave inconsistent results.

3. Beans having a white skin with associated low tannin content, did not support significantly higher egg production than did a normal brown‐skinned bean, thus indicating that tannin was not the main anti‐nutritive factor.

4. A cotyledon fraction, obtained by mechanical removal of the tannin‐containing skin from brown beans, did not support higher egg production than did the whole bean, and the corresponding brown‐skin fraction did not reduce egg production when substituted for cereal in the control diet. Again this indicated that tannin was not implicated.  相似文献   

999.
1. Dry rabbit excreta were found to contain 188.1 g crude protein, 6.6 g non‐protein nitrogen, 0.3 g ammonia, 89.8 g moisture, 8.0 g ether extractives, 135.2 g crude fibre, 266.9 g ash and 19.18 MJ gross energy/kg. Methionine and lysine contents were 3.95 and 4.29 g/100 g protein, respectively.

2. In one experiment, 0, 50, 100 or 200 g rabbit excreta/kg were substituted for maize in a broiler diet. Chickens receiving the diet containing 200 g rabbit excreta/kg gained significantly less weight to 8 weeks of age than those receiving other diets.

3. In a second experiment, 0, 100, 150 or 200 g rabbit excreta/kg were substituted primarily for maize in a broiler diet to provide equal energy and protein contents. Weight gains to 8 weeks of birds receiving these diets did not differ significantly. The uncorrected metabolisable energy content of the excreta was 9.15 MJ/kg.

4. There were no gross pathological changes in the birds fed on the experimental diets.  相似文献   

1000.
Chickens contact-exposed to lymphoid leukosis virus at various ages up to 32 weeks responded with relatively high rates of infection as determined by the presence of neutralizing antibody. Virus shedding as determined by cloacal swab and albumen testing occurred in 7 of 8 groups of such chickens, but the incidence was 10% or less and sporadic. Vaccination of chickens immediately before exposure with a low pathogenicity virus of subgroup A at 8 weeks of age did not eliminate subsequent shedding.  相似文献   
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