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791.
研究了新配体TTBA与二价锌离子生成配合物的光度特征。在较宽的pH范围内.新试剂和锌离子形成1:1的谈黄色配合物.稳定常数K=5.36×105’,λmax=310urn表观摩尔吸光系数ε=2.35×105l/moL·cm,并且在3.8×10-8~1×10-5mol/L范围内具有良好的线性关系。 相似文献
792.
793.
22~42日龄肉鸡铜、铁、锌、锰不同用量组合的研究 总被引:1,自引:0,他引:1
本试验旨在研究饲粮中铜、铁、锌、锰含量对22~42日龄肉鸡生长性能和粪中铜、铁、锌、锰排泄量的影响,进而对微量元素的平衡模式进行探讨。选取940只1日龄爱拔益加(AA)肉公鸡,1~21日龄统一饲喂铜、铁、锌、锰含量分别为16.96、166.66、46.01、60.26 mg/kg的玉米-豆粕型饲粮。试验选用22日龄、体况良好、体重接近的AA肉公鸡900只,随机分为15组,每组6个重复,每个重复10只鸡。对照组饲喂基础饲粮,基础饲粮中铜、铁、锌、锰含量分别为8、125、40、60 mg/kg,试验组饲喂在基础饲粮中按照均匀设计原则添加2~8 mg/kg铜、10~35 mg/kg铁、10~40 mg/kg锌、15~60 mg/kg锰组成的14种试验饲粮。测定肉鸡试验期生长性能,并于38~42日龄时采集粪样测定铜、铁、锌、锰含量。结果表明:1)饲粮铜、铁、锌、锰含量在NRC推荐量至2倍NRC推荐量范围时,对22~42日龄肉鸡的平均日增重(ADG)和料重比(F/G)无显著影响(P0.05)。2)由最优解分析得出,粪中铜排泄量最低为23.11 mg/kg时,饲粮铜、铁、锌、锰含量分别为7.15、116.28、82.82、60.95 mg/kg;铁排泄量最低为438.34 mg/kg时,饲粮铜、铁、锌、锰含量分别为14.78、116.81、38.15、63.72 mg/kg;锌排泄量最低为102.60 mg/kg时,饲粮铜、铁、锌、锰含量分别为7.69、127.40、40.70、133.26 mg/kg;锰排泄量最低为159.37 mg/kg时,饲粮铜、铁、锌、锰含量分别为11.07、136.97、46.13、59.05 mg/kg;粪中铜、铁、锌、锰总排泄量最低为218.94 mg/kg时,饲粮铜、铁、锌、锰含量分别为7.36、125.74、38.23、62.76 mg/kg。综上所述,饲粮铜、铁、锌、锰含量在NRC推荐量至2倍NRC推荐量范围时对22~42日龄肉鸡的生长性能无显著影响;粪中铜、铁、锌、锰任一元素的排泄量均受饲粮中其他微量元素添加量的影响,且针对不同元素最低排泄量存在不同的最佳组合;饲粮铜、铁、锌、锰的含量分别为7.36、125.74、38.23、62.76 mg/kg时,能够满足肉鸡微量元素需要量,同时粪中铜、铁、锌、锰总排泄量最小。 相似文献
794.
氮、磷、钾、锌配施对小白菜产量和品质的效应 总被引:5,自引:2,他引:5
应用“416-B”最优混合设计,研究了氮、磷、钾、锌肥对小白菜产量和品质的效应。结果表明,施用氮、磷、钾、锌的增产效果为氮〉锌〉钾〉磷。氮与磷、钾、锌配施有利于小白菜增产和品质的改善。在本试验条件下,小白菜高产、优质施肥方案为每千克土施N0.26g、P2O5 0.11g、K2O 0.42g、Zn0.017g,目标产量790.7g/盆FW,鲜小白菜中含锌81.9mg/kg,可溶性糖1.63%,Vc117.9mg/kg,硝酸盐809.5mg/kg。 相似文献
795.
796.
Our aim was to establish the long-term effects of repeated applications after 20 y of organic amendments (farmyard manure at 10 t ha−1 y−1, and urban sewage sludge at two different rates, 10 t ha−1 y−1 and 100 t ha−1 every 2 y) on the quality of a sandy and poorly buffered soil (Fluvisol, pH 6). Chemical characteristics and biodegradability of the labile organic matter, which is mainly derived from microbial biomass and biodegradation products of organic residues, were chosen as indicators for soil quality. The organic C content had reached a maximal value (30.6 g C kg−1 in the 100 t sludge-treated soil), i.e. about 2.5 times that in the control. Six years after the last application, the organic C content and the microbial biomass content remained higher in sludge-treated soils than in the control. In contrast, the proportion of labile organic matter was significantly lower in sludge-treated soils than in manure-treated and control soils. The labile organic matter of sludge extracts appeared less humified than that of manure-treated and control soils. 相似文献
797.
O. Nagafuchi R. Suda H. Mukai M. Koga Y. Kodama 《Water, air, and soil pollution》1995,85(4):2351-2356
Rime-ice and snow samples were collected at mountain sites in Kyushu, Japan during the winter of 1994, and both soluble and insoluble substances in the melted rime-ice were analyzed by ion chromatography, inductively coupled plasma-mass spectrometry (ICP/MS) and analytical electron microscopy, in order to find the evidences of long-range transport of air pollutants from the cities of the East Asian region. The relationships between Al, which is most often used as an index of soil components, and other elements were examined. The positive correlation was found between Al and three elements (Ti, Mn, Ba). Therefore, behaviors of these elements in rime-ice may be similar to that of soil particles. Furthermore, it was possible to classify the elements into three groups with the relation between a lead isotope ratio and concentration ratio of lead and zinc (Pb/Zn). In addition, numbers of particles were found in the rime-ice. The particles around 1 m in diameter were considered to be the combustion products of coal, whose Pb/Zn were similar to that of previous survey report in Korea. The existent forms of chemical species in rime-ice will become an important factor, when we consider the origin of air pollutants transported over long distances in the East Asian region. 相似文献
798.
《Communications in Soil Science and Plant Analysis》2012,43(17):2039-2045
A pot experiment was done to study the effect of zinc (Zn) application on the reproductive development and quality of wheat (Triticum aestivum L. cv. SP 343) seeds. The soil was low in diethylenetriaminepentaacetate (DTPA)–extractable Zn and was fortified with a mixture of nitrogen, phosphorus, and potassium (NPK) as basal fertilizers. Four treatments included a control (no Zn), 5 mg Zn, 10 mg Zn, and 10 mg Zn kg?1 soil with urea instead of ammonium nitrate. Zinc addition improved the pollen-producing capacity of anthers, pollen viability, and seed yield with an increase in seed Zn, phytate, and starch contents but decreased the phytate/zinc molar ratio at 5 mg Zn kg?1 and increased it at 10 mg Zn kg?1. Application of urea increased the seed protein content at 10 mg Zn kg?1 but was ineffective in lowering the phytate/Zn ratio, which was still less than the alarming level. 相似文献
799.
《Communications in Soil Science and Plant Analysis》2012,43(9):785-798
Abstract Three types of sewage sludge are applied to the surface of soil columns of Coastal Plain soils and leached with distilled water. The Zn concentrations in leachate samples from a Sassafras loamy sand soil loaded with an industrial sludge increased with sludge loading rate. All leachate samples contained very low concentrations of Cd, Cr and Cu. Hazardous amounts of Cd, Cr, Cu and Zn would not be leached to the groundwater when recommended rates of the tested sludges are applied to Coastal Plain soils under most conditions. 相似文献
800.
通过对盛花期紫花苜蓿(Medicago sativa)进行叶面喷施不同质量分数的硼、钼、锌,测定不同处理下紫花苜蓿种子产量、株高、千粒重、花序数/生殖枝、豆荚数/花序、籽粒数/豆荚等产量构成因素。结果表明,硼、钼、锌对紫花苜蓿种子产量及其构成因素有显著效应。3种微肥中0.9%硼、0.04%钼和0.6%锌处理对苜蓿种子具有良好的增产效果,种子产量分别比对照增加6.89%、26.51%和13.8%,其中0.04%钼增产效果最优。同时各处理对花序数/生殖枝、荚果数/花序、籽粒数/荚果等均有一定影响。 相似文献