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11.
Majorera goat kids (n = 200) were used to evaluate the effects of litter size, birth body weight, sex, and suckling duration on serum IgG concentrations. Kids were assigned to 1 of 3 experimental groups: litter size and sex were equally distributed in each group. In the first group, kids (n = 67) stayed with their dams for 24 h; in the second group, kids (n = 66) stayed with their dams for 48 h; and in the third group, kids (n = 67) stayed with their dams for 120 h. Blood samples were obtained every 24 h for 5 d, and serum IgG concentration was measured using radial immunodiffusion. In litter sizes of 1 to 2 kids, IgG blood serum concentration was significantly higher (18.30 ± 5.40 mg/mL) than in litters of 3 kids (9.85 ± 4.23 mg/mL). Kid sex did not affect IgG blood serum concentrations. Suckling duration did not affect kid serum IgG concentrations. In conclusion, kids with low birth body weight (<2.8 kg) or from litters of 3 may need special attention. If newborn goat kids are allowed to suckle colostrum for at least 24 h from their dams, this seems to be sufficient time to ingest enough IgG from colostrum to achieve an adequate serum IgG concentration and passive immune protection to avoid failure of passive immune transfer. 相似文献
12.
Co-combustion of chicken litter (CL) with coal was performed in a laboratory-scale fluidized bed combustor to investigate the effect of CL combustion on pollutant emissions. The emissions of major gaseous pollutants including CO, SO2, H2S and NO and temperature distribution along the combustor were measured during the tests. Effects of CL fraction and secondary air on combustion characteristics were studied. The experimental results show that CL introduction increases CO emissions and reduces the levels of SO2. The ratio of H2S/SO2 increases with increasing fraction of CL. NO emissions either increase or decrease depending on the percentage of CL in the mixed fuels. The temperature in the freeboard region increases with increasing the fraction of CL while the reverse is true for the bed temperature. 相似文献
13.
Lufei JiaEdward J. Anthony 《Fuel Processing Technology》2011,92(11):2138-2144
Poultry farming generates large quantities of waste. The current practice is to spread this waste onto farmland as fertilizer. However, as the factory farms for poultry grow both in numbers and size, the amount of waste generated has increased significantly in recent years. In consequence, excessive application of poultry wastes on farmland is resulting in more and more nutrients entering the surface water. One of the options being considered is the use of poultry waste as power plant fuel. Since poultry-derived fuel (PDF) is biomass, its co-firing will have the added advantage of reducing greenhouse gas emissions from power generation. To evaluate the combustion characteristics of co-firing PDF with coal, combustion tests were conducted in CanmetENERGY's pilot-scale circulating fluidized bed combustor (CFBC). The goal of this program was to verify that PDF can be co-fired with coal and, more importantly, that emissions from the combustion process are not adversely affected by the presence of PDF in the feed. The test results were very promising and support the idea that co-firing in an existing CFBC boiler firing coal is a good way to utilize PDF, resolving a potential waste disposal problem while reducing the amount of CO2 released from the boiler. 相似文献
14.
钛白废酸浓缩副产物"黄泥巴"是钛白生产过程中形成的一种危险废弃物。其具有成分复杂,杂质含量多,储藏和运输不便等特点,不能作为产品直接销售。笔者通过多次深入研究和实验,探索出了"黄泥巴"制取高蓝相铁黑颜料的工艺条件。 相似文献
15.
Toshihiko Ohnuki Fuminori Sakamoto Naofumi Kozai Shinya Yamasaki Yoshito Sasaki Tadafumi Niizato 《Journal of Nuclear Science and Technology》2019,56(9-10):814-821
ABSTRACTWe used the spent mushroom substrata (SMSs) which are a kind of by-product after growing edible mushrooms for the in-situ investigation of radioactive Cs mobility in litter zone in a forest of Fukushima prefecture, Japan. The powder SMS was filled in a plastic net bag of 0.35 × 0.55 m, then was placed in a forest for ~6 months under three kinds of different conditions without treatment (No treatment), covered with wooden box (With box), and with zeolite placed on upper position of ground surface (With zeolite). We determined the ratio of radioactivity (TF) in the SMS to that of the soil and litter beneath the SMS bags. TFs of ‘No treatment’ and of ‘With zeolite’ were determined between ~0.01 and ~0.05 for 6 months. On the other hand, TFs of ‘With box’ were lower by one order at 2 and 4 months than those of ‘No treatment’ and of ‘With zeolite,’ and nearly the same values as TFs of ‘No treatment’ and ‘With zeolite’ at 6 months. These results clearly indicate that radioactive Cs accumulates in SMS mainly by throughfall. In addition, for a period of several months, fungi contribute to the accumulation of radioactive Cs in the litter zone, even though radioactive Cs was tightly associated with the soil. 相似文献
16.
项磊 《电信工程技术与标准化》2010,23(7)
光缆物理网作为最贴近用户的战略性资源,是争夺业务的关键性基础物理网络。如何为光通信设备提供安全、经济和便利的供电,是通信运营商和建设者非常关心的课题。本文简要介绍了远程光通信设备的供电方式及需要考虑的相关问题。 相似文献
17.
In order to develop fuel models used as input in wildland fire propagation models, it is necessary to determine relevant vegetation properties concerned with the prediction of the combustion process. This research considers property measurements of two biomass species, namely Pinus halepensis and Pinus brutia. Both species are commonly found in Greece and other Eastern Mediterranean countries. The physical application of the biomass properties relates to the structure of pine forest litter. Measurements have been recorded of the characteristics of the litter layer in situ, and common fuel properties have been determined in the laboratory using samples of the two litter species. In addition, DTA, TG and DTG analysis were performed of the two litter species. The results of the measurements are presented in a format suitable for input in fire propagation models. Comparisons of data have been made with those from other literature sources. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
18.
Tannins are ubiquitous in higher plants and also in litter and soils where they affect many biogeochemical processes. Despite this well-recognized role, their fate in litter and mineral soils is hardly known, as often only trace amounts, if any, are measured. In this study, we conducted an incubation experiment with Corsican pine litter to which known amounts of tannic acid (TA) or condensed tannins (CTs) from Corsican pine were added. Using Folin–Ciocalteu as a measure for total phenolics and HCl–butanol as an assay specific for CTs, acetone/water extractable phenolics and tannins decreased with time towards very low levels. Application of thermally assisted hydrolysis and methylation to litter before and after acetone/water extraction revealed that TA concentration decreased. By contrast, CTs remained to a great extent in the litter and could not be extracted suggesting that they were tightly bound. 相似文献
19.
Amanda Acero James P Muir Richard M Wolfe 《Journal of the science of food and agriculture》2010,90(15):2582-2585
BACKGROUND: The role of condensed tannins (CT) in ruminant nutrition and health makes changes in leaf litter (LL) after abscission of interest. This study compared the effect of different drying methods of green leaves (GL) with that of natural drying of LL on CT, fibre, crude protein (CP) and phosphorus (P) concentrations in nine Texas browse species. Leaves harvested before autumn shedding were oven‐dried (OD) or freeze‐dried (FD). RESULTS: Where different (P < 0.05), extractable CT concentrations were higher while protein‐ and fibre‐bound CT concentrations were lower in GL‐FD than in LL. Drying method changed total CT concentration in three species. Where different, fibre fraction concentrations were greater in LL than in GL, regardless of drying method. In some species, CP and P concentrations were lower in LL than in GL, but in five species they did not change (P > 0.05) from GL to LL, with CP concentrations ranging from 63 to 151 g kg?1 in the latter. CONCLUSION: Browse LL had high nutritive value and CT concentrations, explaining why browsing ruminants utilise this feed resource. However, changes in nutrient and CT concentrations as leaves become litter in some species mean that information on one is not necessarily applicable to the other. Copyright © 2010 Society of Chemical Industry 相似文献
20.