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81.
简述了在团粒法工艺的基础上,用尿素熔融尿液或尿素车间二段蒸发器的尿液进行喷浆造粒生产复合肥的改造方案、改造内容、改造效果和投资情况。 相似文献
82.
The phosphate sorption isotherms are needed to explain differential plant responses to P fertilization in soils. Laboratory and greenhouse experiments investigated the use of phosphorus sorption isotherms in relation to P fertilizer requirement of wheat in ten benchmark soils of Punjab, India. The modified Mitscherlich Equation (3) was used to describe plant response observed in different soils. Maximum obtainable yield (MOY) ranged from 11.6 g pot–1 in Gurdaspur (I) sandy clay loam to 7.0 g pot–1 in Nabha sandy clay loam. Response to P applied @ 25 mg P kg–1 soil was maximum (77%) in Bathinda sand and minimum in Chuharpur clay loam (33%). The response curvature varied from 3.74 × 10–2 in Nabha sandy clay loam to 4.43 × 10–2 in Kanjli sandy loam. The soil solution P required to produce optimum yield (90% MOY) varied from 1.61 µg ml–1 in Bathinda sand to 0.10 µg ml–1 in Sadhugarh clay. Dry matter yield obtained at 0.2 µg ml–1 solution P concentration ranged from 55% in Bathinda sand to 85% of MOY in Gurdaspur (II) clay loam. At the same solution P concentration (0.1 µg P ml–1), dry matter yield was 91% in Sadhugarh clay, 80% in Gurdaspur (II) clay loam and, 43% of MOY in Bathinda sand and eventually coincided with the decreasing maximum buffer capacity (MBC) in these soils. At the same level of sorbed P (100 mg P kg–1 soil) the yield was observed to be inversely proportional to MBC. The study, therefore, concludes that, soils should be grouped according to their P sorption characteristics and MBC before using critical soil solution P as a criterion for obtaining optimum yields. 相似文献
83.
In a field study P and K uptake by two corn (Zea mays L.) genotypes which differed in root growth was investigated. The effect of differences in root growth on P and K uptake was assessed using a mechanistic-mathematical model which describes nutrient uptake by growing plant roots in soil. Nitrogen was applied at 0 and 227 kg ha–1 to Pioneer 3732 and B73xMo17 corn grown on Raub silt loam (fine-silty, mixed, mesic Aquic Argiudoll) and at 227 kg N ha–1 to these two genotypes on Chalmers silt loam (finesilty, mixed, mesic, Typic Haplaquoll). Root growth and P and K uptake by the two corn genotypes was measured 31, 47, 75 and 91 d after planting on the Raub and 31, 47, 61 and 75 d after planting on the Chalmers soil.Root growth and P and K uptake by B73xMo17 was greater than that of Pioneer 3732 on N-fertilized Raub soil. On Chalmers soil the difference in root growth between the two genotypes resulted in an increase in K but not P uptake. The higher soil P level of the Chalmers appears to have offset possible differences in P uptake due to root size. There were no differences between the two genotypes in either the percentage of roots with root hairs, or the density or length of root hairs. Phosphorus and K uptake calculated with the simulation models for both corn genotypes on both soils over each of three growth periods agreed with observed P (Y = 0.68X + 1.71; r = 0.944**) and K (Y = 0.88X + 15.52; r = 0.928**) uptake. Differences in P and K uptake between B73xMo17 and Pioneer 3732 resulted primarily from the difference in root growth in the topsoil. A high correlation was found between root surface area and P (r = 0.893**) and K (r = 0.928**) uptake by both corn genotypes on both the soils.Journal paper No. 10,316 Purdue Univ. Agric. Exp. Stn., W. Lafayette, In 47906. Contribution from the Dep. of Agron. This paper was supported in part by a grant from the Tennessee Valley Authority. 相似文献
84.
Intensification of agriculture by irrigation and enhanced use of fertilizers may generate pollution by increased levels of nutrients in underground and surface waters. Most of the irrigation is by open systems having a relatively low efficiency of water application. A higher efficiency may be gained by pressurized irrigation systems. Drip irrigation generates a restricted root system requiring frequent nutrient supply that may be satisfied by applying fertilizers in irrigation water, i.e. by fertigation. Maximization of crop yield and quality and minimization of leaching below the rooting volume may be achieved by managing fertilizers concentrations in measured quantities of irrigation water, according to crop requirements. 相似文献
85.
以氟碳气体为超声造影剂,通过接枝纳米磁性颗粒-RGD多肽,构建靶向蛋白质超声微泡,制备一种可同时用于超声造影和磁共振成像(MRI)的双模态造影增强剂。通过显微镜对磁性蛋白超声微泡形貌进行观察,利用红外光谱、分光光度法分析纳米磁性颗粒接枝牛血清蛋白的接枝率,并通过细胞实验评价磁性蛋白微泡的生物相容性。 相似文献
86.
采用CuO-ZnO/Al2O3纳米铜基催化剂催化4-异丁基苯乙酮(IBAP)加氢制备1-(4-异丁基苯基)乙醇(IBPE);然后以PdCl2/PPh3/CuCl2为催化体系,将IBPE经羰基化反应合成2-(4-异丁基苯基)丙酸(布洛芬)。研究结果表明:在反应温度80℃,氢气压力1.5MPa,n(H2)∶n(IBAP)=40∶1,液空速0.30h-1的条件下,IBAP的加氢转化率为100%,IBPE收率达到93.6%。以盐酸为酸性介质、丁酮为溶剂,在温度100℃,CO压力5.5 MPa,反应时间24h的条件下,IBPE羰基化合成布洛芬,IBPE的转化率为100%,布洛芬收率达到72.9%。 相似文献
87.
以自制的谷氨酸-氟硼酸(GluBF4)离子液体水溶液为反应介质,以物质的量比为1∶6的二水合醋酸锌[Zn(Ac)2·2H2O]和NaOH为原料,室温(25℃,20min)制备前驱体,再微波辅助加热(80℃,10min)制备了纳米氧化锌粉体,获得了纳米结构微米尺寸ZnO绒球。利用场发射扫描电子显微镜(FESEM)、X射线衍射(XRD)、比表面积(BET)、能谱(EDS)等对产物进行了表征。结果表明,所得产物为六方晶系纤锌矿结构,粉体粒径20.4nm,绒球比表面积为27.6m2/g。该纳米材料具有较高的光催化降解有机污染物活性。以紫外光为光源,50 mg微/纳米ZnO绒球为光降解催化剂,取500mL北京雪莲羊绒股份有限公司排污口混合印染污水进行光降解实验,在30min内光降解效率达到了100%,催化剂可回收重复利用,并对光降解机理进行了初步分析。 相似文献
88.
潘强 《河南城建高等专科学校学报》2014,(3):53-56
研究了一种基于聚硫堇/纳米金复合材料修饰电极对NO2-的电催化氧化。相对于裸玻碳电极,聚硫堇-纳米金协同催化效应使NO2-的氧化电流增强,过电位降低。详细讨论了聚合膜的厚度、纳米金吸附时间、pH缓冲介质、pH值以及干扰离子对NO2-氧化电流的影响。在最优实验条件下,测得NO2-的线性范围为3.0×10^-6~1.0×10^-3 mol/L,检测限为1.0×10^-6 mol/L。该修饰电极具有灵敏度高、稳定性和重现性好、抗干扰能力强的特点,可用于实际样品中NO2-含量的测定,结果满意。 相似文献
89.
Bingrong Li Yaowu Wei Jinhu Wang Junfeng Chen Nan Li 《Journal of the American Ceramic Society》2021,104(9):4878-4890
Well-sintered CaO granules with hydration resistance are very important for the manufacturing and application of CaO-containing refractories. CaO granules with sol-processed metal oxide protective layers were prepared by granulation and surface treatment. The obtained results indicated that the usage of nano sol greatly improved the hydration resistance of CaO granules, especially when the CaO granules were treated by alumina sol. The promoting effect of nano sols in the sintering processes improved the density of CaO granules. Nanoparticles reacted with lime at lower temperature and a new phase was formed uniformly in the treated layer, which promoted densification of the treated layer. The grain size of CaO granules in the treated layer was increased obviously with the promotion of sintering. Moreover, nanoparticles were favorable for the formation of direct bonding between CaO grains by decreasing the dihedral angle. 相似文献
90.
采用双转子连续混炼挤出机与微纳层叠共挤出成型设备制备了聚丙烯/聚酰胺6/碳纳米管(PP/PA6/CNTs)复合材料和原位微纤复合膜,通过扫描电子显微镜(SEM)、流变仪、差示扫描量热仪(DSC)、万能拉伸试验机及电阻测试仪对其微观结构、流变性能、结晶性能、力学性能和导电性能进行了表征。结果表明,与共混相比,微纳层叠共挤出法使得分散相PA6/CNTs形成了微纤,微纤的形成不仅提升了复合膜的动态流变性能,并且增加了基体PP相的结晶度,提高了PA6相的结晶温度,提升了复合膜的结晶性能;当CNTs含量为0.5 %(质量分数,下同)时,复合膜的拉伸强度和断裂伸长率均达到最大值,分别为42.17 MPa和857.82 %,体积电阻率(R)下降到104 Ω·cm,综合力学性能和导电性能达到最佳。 相似文献