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11.
Abstract. A two year field experiment was carried out in a semiarid Mediterranean area in order to evaluate, the effect on soil erosion of adding different urban organic wastes: a stabilized municipal waste (compost), an unstabilized municipal waste, and an aerobic sewage sludge. All the treatments significantly reduced soil erosion, compared to the control soil. The soil amended with compost was the most effective treatment, reducing soil loss by 94% and runoff by 54%.  相似文献   
12.
赵强基 Garr.  DD 《作物学报》1993,19(5):402-411
在菲律宾的雨养旱地、雨养低地和灌溉田种植制度研究基点上,分别对各种农民和拟推广的实验种植方式,进行了生物量及其组成、作物分器官的 C、N、P、K 含量与分布比率、作物残茬燃烧后 C、N、P、K 损失测定。从添加与取走两个方面,分三种添加与取走情况,计算了土壤N、P、K 的部分养分平衡与有机质平衡。结果显示:在当地施肥水平下,即使归还全部残茬,很难维持 N、P、K 的养分平衡,但能较好满足土壤有机质平衡。为维持土壤有机质的年平衡,雨养低地和雨养旱地需分别归还1400和1900公斤生物物质/公顷.年。并对当地维持养分平衡的途径作了分析与探讨。  相似文献   
13.
Campylobacter numbers on broiler carcasses can increase dramatically during defeathering because of leakage of contaminated gut contents in the feather-picking machine. Food-grade organic acids have been shown to be effective in killing bacteria. Placement of organic acids into the cloaca prior to defeathering was tested to determine if such a treatment could lower the number of Campylobacter that escape and contaminate broiler breast skin during automated feather removal. Campylobacter numbers on the breast skin of treated carcasses increased during defeathering but resulted in numbers that were only about 2% of those observed on control carcasses. Placement of food-grade organic acids in the cloaca of broiler carcasses may be useful as a means to lessen the impact of automated defeathering on the microbiological quality of carcasses during processing.  相似文献   
14.
将微波加热干燥技术和滤纸水分蒸发强化技术应用于全乳固体的快速测定.比较了该方法与GB5409-85减重法的差异和对乳中热敏物质乳糖稳定性的影响及测定结果的差异。经t检验得出了两种方法对乳糖的含量变化的差异不显著,全乳固体含量的测定结果相同,将测定时间由240min缩短至37min,可以满足生产对全乳固体快速测定的时间要求。  相似文献   
15.
提出了以聚乙烯吡咯烷酮(PVPr)修饰碳糊电极测定水中苯酚的方法.在0.1mol/LKCl的酚试液中开路富集后,在磷酸盐缓冲液介质(pH5.6)中溶出,用微分脉冲伏安法测定,苯酚的溶出峰电位为+0.73V(Ag-AgCl参比电极),检测限为0.05μg/L.应用该法测定了废水中苯酚的含量,并讨论了该法测定苯酚的影响因素,比较了几种修饰电极测定苯酚的灵敏度,探讨了苯酚在该修饰电极上的富集机理  相似文献   
16.
Objective: To evaluate the ability of capnography to document proper placement of nasoesophageal (NE) and nasogastric (NG) feeding tubes. This study was conducted in 3 phases. Phase I of this study was designed in order to test the efficacy of capnography to distinguish placement of a feeding tube in the alimentary tract versus the respiratory tract. Phase II was designed in order to document that carbon dioxide (CO2) could be measured through a polyvinyl chloride (PVC) feeding tube. Phase III was performed in order to evaluate the technique of continuous monitoring during insertion of the feeding tube into the esophagus and stomach as would be performed during a clinical‐tube placement. Design: Prospective study. Setting: Research laboratory. Animals: 24 adult dogs. Interventions: In Phase I, sedated dogs were instrumented with an intratracheal catheter and an 8 French feeding tube placed nasally into the distal esophagus and later advanced into the stomach. In Phase II, dogs were anesthetized and an 8 French feeding tube was placed down the endotracheal tube, then into the esophagus and later advanced into the stomach. In Phase III, sedated dogs were instrumented with an 8 French feeding tube inserted intranasally and then advanced to the level of the nasopharynx, distal esophagus and, lastly, the stomach. Fluoroscopy was used in order to determine location of the feeding tube. Measurements and main results: Phase I measurements included respiratory rate and CO2 from the trachea, esophagus, and stomach and pH of gastric fluid sample. Phase II measurements included respiratory rate and CO2 from the endotracheal tube, feeding tube in the endotracheal tube, feeding tube in the distal esophagus, and feeding tube in the stomach. Phase III data collection included respiratory rate and CO2 as the tube was passed through the nasal cavity, nasopharynx, esophagus and stomach. Phase I fluid samples were collected from 5 of the 9 dogs and had pH values from 1.68 to 4.20. In both phases, values for the respiratory rate and CO2 from the esophagus and stomach were 0 ± 0, significantly lower (P < 0.001) than the values from the trachea. In Phase II, there was no significant difference between the respiratory rates (P = 0.886) and CO2 (P = 0.705) readings obtained from the endotracheal tube compared to readings from the feeding tube in the endotracheal tube. In Phase III, there was a significant difference (P < 0.001) between the respiratory rates and CO2 readings obtained from the nasal cavity and the nasopharynx when compared to those readings obtained from the esophagus and stomach. Measurement of CO2 and respiratory rate resulted in a reading of 0 every time the feeding tube was in the esophagus or stomach. Conclusions: Capnography may be used in order to detect airway placement of NE and NG tubes.  相似文献   
17.
18.
Sandy‐textured Mediterranean soils are invariably depleted in organic matter and supply only small amounts of N to crops. To compensate for these deficiencies, we tested the N supply from six organic wastes applied to a Cambic Arenosol in pots growing ryegrass. The results showed that the behaviour of the wastes in supplying N to a ryegrass crop grown in this soil can be predicted by observing their performance in laboratory aerobic incubations. The N made available during these incubations fitted well to a one‐pool kinetic model.  相似文献   
19.
保定市工业废水农灌的研究   总被引:1,自引:0,他引:1  
本文论述了保定市工业废水经农灌土地处理,对土壤、地下水和农作物品质的影响。结果表明:以造纸、食品、轻纺和化工为主的工业废水在重金属常年不超出农灌标准下,宜于在非盐化土壤灌溉;废水中硫化物超标,通过土壤生物区系,能降低毒性;废水中常规有机物,农灌后利大于害;只要在土壤容量允许内,可具有二级污水处理工艺不能完成的效果。  相似文献   
20.
用通径分析的方法分析了不同形态硫对土壤有机质的作用。结果表明 :在影响土壤有机质的诸多硫组分中 ,以全硫为主 ,其次是未知态硫和全硫的共同作用 ,再次是碳键硫和全硫的共同作用 ,脂键硫排在第九位。有机硫起主要作用  相似文献   
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