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排序方式: 共有51条查询结果,搜索用时 31 毫秒
1.
研究了施用鸡粪土壤中磷养分在自然降雨过程中随地表径流流失的变化规律.结果表明:颗粒附着态磷(PP)占总磷(TP)的61.1%~79.5%,是土壤中磷索在自然降雨过程中随地表径流流失的主要形态.基于作物需磷量计算鸡粪用置较基于作物需氮量能有效降低地表径流中不同形态磷浓度,其中TP降幅为8.0%~46.3%.PP降幅为6.0%~48.2%.TDP降幅为15.1%~46.0%,DIP降幅为29.4%~55.5%.表明基于作物需磷量计算鸡粪施用量能有效降低土壤中磷索在自然降雨过程中随地表径流的流失风险.添加沸石或铁盐可有效降低地表径流中TP和PP浓度,从而有效降低磷随地表径流损失的风险.  相似文献   
2.
以HZSM-5为载体,通过浸渍法制备不同NiO负载量的NiO/HZSM-5催化剂并进行表征,发现负载量为8%的催化剂表面形貌相对平整,比表面积、酸位等特性较理想。通过生物油模拟物催化试验对催化剂性能进行评价,试验结果表明负载量和反应温度都对催化剂活性有明显影响。在反应温度为400℃时,负载量为8%的催化剂使模拟物中甲苯和愈创木酚具有较好的转化率,分别达到83%和88%;较HZSM-5催化的情况分别提高60%和70%。改性后生物油的热值也可增加约30%。负载物NiO的加入使催化剂表面强酸位降低约45%,同时提高了催化剂的稳定性和抗积碳能力,延长了催化剂使用寿命,其中8-ZSM-5催化剂在反应6 h后仍保持较高活性。  相似文献   
3.
沸石复混肥对油菜苗期养分吸收、产量及土壤性状的影响   总被引:1,自引:0,他引:1  
在盆栽条件下,比较了不同沸石含量的沸石复混肥对盆栽油菜苗期不同阶段N、P、K养分吸收量,油菜籽产量及土壤性状的影响.结果表明:沸石复混肥处理与对照复混肥比较,在苗期的前2个月,油菜吸收的N、P、K均为前者大于后者,而在第3个月开始,为后者大于前者.从整个苗期来看,相比复混肥对照,沸石复混肥处理的油菜N、P、K养分吸收量均有所下降,其中磷吸收量随沸石复混肥中沸石比例的增大而明显下降.沸石能减轻土壤酸化程度,提高土壤pH值,降低EXC-Mn.沸石在复混肥中的比例以10%~15%的含量较为合适,相比对照复混肥,增产可达9.7%.  相似文献   
4.
5.
日粮中添加沸石对肉兔生长的影响   总被引:2,自引:0,他引:2  
为探讨沸石对肉兔生长的影响,将40只60~70日龄加利福尼亚幼兔随机分成4组。Ⅰ组为对照组,饲喂基础日粮,另外3组分别在基础日粮中添加3%、6%和9%沸石。结果表明,在每千克饲料含可消化能110MJ、粗蛋白质160%的日粮中,添加3%~5%的沸石,可促进幼兔生长,降低饲养成本,提高养兔效益。  相似文献   
6.
在合成沸石存在下苧烯、α-蒎烯及2(10)-蒎烯的水合反应   总被引:1,自引:1,他引:1  
本文测定了中国和日本产各种沸石的组成和性质,并在沸石的存在下进行了苧烯、α-蒎烯和2(10)-蒎烯的水合反应试验,鉴定了水合反应的生成物,初步探讨了中、日两国所产沸石对反应结果的影响,提出了沸石用于萜烯水合反应的一些基础数据。  相似文献   
7.
An experiment was conducted to determine how an E. coil challenge and dietary clays affect the intestinal barrier of pigs. Two groups of 32 pigs (initial BW: 6.9 ± 1.0 kg) were distributed in a 2 x 4 factorial arrangement of a randomized complete block design (2 challenge treatments: sham or E. coil, and 4 dietary treatments: control, 0.3% smectite A, 0.3% smectite B and 0.3% zeolite), with 8 replicates total. Diarrhea score, growth performance, goblet cell size and number, bacterial translocation from intestinal lumen to lymph nodes, intestinal morphology, and relative amounts of sulfo and sialo mucins were measured. The E. coli challenge reduced performance, increased goblet cell size and number in the ileum, increased bacterial translocation from the intestinal lumen to the lymph nodes, and increased ileal crypt depth. One of the clays (smectite A) tended to increase goblet cell size in ileum, which may indicate enhanced protection. In conclusion, E. coli infection degrades intestinal barrier integrity but smectite A may enhance it.  相似文献   
8.
非金属矿物改良皖南酸性红黄壤应用研究   总被引:1,自引:0,他引:1  
应用非金属矿物沸石(尿素沸石)、白云石改良皖南地区酸性红黄壤,结果表明:盆栽玉米、大豆植株干物重增加39.4%-54.5%,NPK吸收量增加25.7%-52.7%;大田试验玉米产量增加23.5%,NPK吸收量增加8.2%-30.6%。沸石(尿素沸石)与白云石配合效果好,是改良酸性红黄壤有效途经。  相似文献   
9.
Water scarcity and soil nitrogen (N) loss are important limitations for agricultural production in semi-arid region especially for rice production. Zeolite (Z) as a soil conditioner can be used to retrain water and nitrogen in near-surface soil layer in lowland rice production system. The objectives of this study were to investigate the effects of different application rates of natural zeolite (clinoptilolite) and nitrogen on rice yield, yield components, soil nitrogen, water use, water productivity in a silty clay soil in 2004 and 2005. Zeolite was only applied in the first year. In order to study the long-term and continuous effect of zeolite on the objectives of the study, no zeolite was applied in the second year and the study was conducted on the same land as the first year. Zeolite and N were applied at rates of 0, 2, 4, and 8 t ha−1 and 0, 20, 40, and 80 kg ha−1, respectively in 2004. In 2005, each plot received the same amount of N as received in 2004. It is concluded that by decreasing N application rates, higher Z application rate is needed to improve grain yield. Highest grain yield was obtained at N application rate of 80 kg ha−1 and Z application rate of 4 t ha−1. Higher grain yield was mostly attributed to lower unfilled grain percentage and higher 1000-grain weight that were a result of higher N application rate and N retention in soil due to Z application. Nitrogen and Z applications resulted in higher grain protein contents and nitrogen recovery efficiency (NRE). Based on these results and due to higher N retention in soil under Z application, improved grain yield quality, nitrogen-use efficiency (NUE), and nitrogen recovery efficiency (NRE) could be obtained at Z application rate of 8 t ha−1 and N application rate of 80 kg ha−1 or more. However, this was not satisfied for NUE. Moreover, it is found that at higher N application rates lower Z application rates are needed to effectively retain soil residual mineral nitrogen. Furthermore, at N application rates of 80 kg ha−1 or more, Z application increased soil water retention and resulted in lower seasonal water use and higher water productivity. In general, it was concluded that the effect of Z application in retaining soil N was also effective in the second year.  相似文献   
10.
陈景茂  吴晋沪  王裕鑫 《安徽农业科学》2011,39(23):14253-14255
[目的]得出稻壳灰合成A型沸石的最佳条件。[方法]利用水热法对稻壳灰合成A型沸石的反应温度、碱浓度、反应物硅铝比和反应时间进行研究。[结果]在水热温度100℃,NaOH浓度为2 mol/L,原料硅铝比为1.0~2.0,反应时间为4~6 h的条件下,可以得到结晶度较高的A型沸石。[结论]该方法工艺简单经济,为生物质灰的利用提供了一种思路,有利于实现完整的生物质能源利用系统,形成可持续发展。  相似文献   
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