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51.
《Communications in Soil Science and Plant Analysis》2012,43(12):1513-1523
Abstract Leaf samples were collected from upper and lower crown positions at three times during the 1971 and 1972 growing seasons for planted black walnut (Juglans nigra L.) trees on the Kaskaskia Experimental Forest in Hardin County, Illinois. The average dry weight of leaves was affected by crown position and time of year. Foliar concentrations of N, P, K, Ca, and Mg were affected by season, but not by crown position. The content of all elements tested and the concentrations of Ca and Mg increased with season while concentrations of N, P, and K decreased as the season progressed. Suggestions for sampling dates are given. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(4):623-630
This study evaluated the suitability of the Mehlic h3 universal extractant as a part of a multielement test to assess the nutrient status of Australian sugarcane soils. Soil samples from BSES Soil Exchange Programs, representing all major soil types and geographic sugarcane-growing regions, were analyzed using existing BSES, acid-based extraction methods for calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), copper (Cu), zinc (Zn), iron (Fe), manganese (Mn), and phosphorus (P) and the ASPAC 10B3 method for sulfur (S). These were compared with the Mehlich 3 procedure. Mehlich 3 results for Ca, Mg, Na, S, and Mn correlated highly with the BSES procedures (R2 = 0.95, 0.98, 0.99, 0.91, and 0.91, respectively). Satisfactory correlations were also obtained with 0.1 M HCl–extracted Zn, Cu, and Fe (R2 = 0.89, 0.85, and 0.85, respectively) and with the BSES sulfuric acid (H2SO4)–extracted P (R2 = 0.81). The poorest correlation (R2 = 0.79) was observed for K. In conclusion, the Mehlich 3 procedure is suitable as a diagnostic tool to assess the basic nutrient status of Australian sugarcane soils. 相似文献
53.
《Communications in Soil Science and Plant Analysis》2012,43(11-12):1627-1638
Abstract In this experiment, when the strontium chloride–citrate acid extractant (0.02 M SrCl2–0.05 M citrate) was used for extraction of calcareous soils with calcium carbonate greater than 70 g kg?1, the filtrate was turbid. Furthermore, white precipitation appeared when this extract was used for phosphorus determination with the Murphy and Riley method. As the concentration of citrate in strontium chloride–citrate acid extractant decreased to 0.025 or 0 M, the filtrate became clean. Further experiments indicated that the 0.02 M SrCl2 extractant could be used as a universal extractant for soil nitrate+nitrite and potassium; the extracted nitrate+nitrite and potassium significantly correlated with nitrogen and potassium phytoavailability, respectively, determined with ryegrass pot experiment (P<0.05). Thus, the 0.02 M SrCl2 was recommended as a universal extractant for soil nitrate+nitrite and potassium. 相似文献
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研究了7-取代-8-羟基喹啉从碱性铝溶液中萃取镓时的萃取效率,认为N-601是一种有工业应用前途的萃取剂。同时,还探索了添加剂加速萃取的效果,结果表明,环烷酸是一种好的添加剂。 相似文献
55.
以采自北京、河北的14个石灰性土壤所进行的微钵栽培番茄所吸收的硼量作为参比标准,研究了曾用于土壤有效硼测定的7种浸提剂的测定值于参比项的相关性。试验结果表明:沸水与沸0.01 mol·L~(-1) CaCl_2溶液浸出硼量基本相同;沸水硼、沸 CaCl_2-B、Morgan-B 和Mehlich 3-B 与番茄植株相对吸硼量的相关系数分别为0.774,0.783,0.764和0.771,均达到极显著水平。说明这4种浸提剂浸出硼量均可作为表征土壤有效硼含量的指数。稀 HCl、NH_4OAc-HOAc 和 DTPA 浸提剂则不适合于石灰性土壤有效硼的浸提。 相似文献
56.
本研究采用马尾松(Pinus massoniana Lamb)单板的多样品在多状态、多溶剂的类型下,进行脱脂试验,确定了较好的萃取剂和工艺条件;还从不同的角度对溶剂的回收工艺、回收率和回收设备进行了探讨,为工业化生产提供了实验依据。 相似文献
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58.
以虎舌红(Ardisia mamillata)为原料,就不同提取剂和操作条件对其总生物碱提取率的影响进行了研究.结果表明,采用酸性乙醇提取要优于酸性水溶液;在60℃下,以pH≈3、φ(C2H5OH)=75%浸泡虎舌红8~10 h,可获得1.36%的提取率;同时考察了活性炭在去除生物碱提取液中的杂质成分的适宜用量. 相似文献
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60.
土壤中有效态镉、汞浸提剂和浸提条件研究 总被引:20,自引:0,他引:20
对不同浸提时间、土液比、浸提剂提取土壤中镉 (Cd)、汞 (Hg)量的影响 ,及各种条件下提取量与水稻吸收相关关系进行研究 ,选择在褐土上土液比 1∶5 ,浸提时间 6 0min ,1mol·L-1NH4 OAc浸提剂提取量表示土壤有效态Cd量较为合适 ;土液比 1∶10 ,浸提时间 30min ,1mol·L-1NH4 OAc浸提剂提取量表示土壤有效态Hg量较为合适 相似文献