改性硝酸铵的工业制备方法及其性能

硝酸铵饱和溶液中加入表面活性剂辛基三甲基溴化铵，采用真空膨胀结晶技术工业制备一种新型改性硝酸铵，并介绍其性能特点。     

无机抗菌磷酸盐玻璃及其性能的研究

采用高温熔融法,在磷酸盐玻璃的配合料中引入抗菌剂硝酸银,一次熔化制得抗菌玻璃材料。通过对磷酸盐玻璃的抗菌性能和缓释性能分析,结果表明:制备抗菌磷酸盐玻璃,合适的银含量为1.5%~2.0%(质量),处理温度在1200~1350℃,即可获得良好的抗菌效果和缓释性。     

偏最小二乘-神经网络光度法同时测定水中的NO3-和NO2-

应用偏最小二乘-神经网络直接解析硝酸根和亚硝酸根的紫外光谱,不经分离紫外吸光光度法同时测定硝酸根和亚硝酸根。在BP算法上,引用改进的误差传递函数,并采用均匀试验设计法确定了最佳网络运行参数。用于水样中硝酸根和亚硝酸根的同时测定,回收率分别为99.0%,105.0%。     

Thermal Expansion Behavior of the Si3N4-Whisker-Reinforced Soda-Borosilicate Glass Matrix Composite

Thermal expansion behaviors of a Si₃N₄-whisker-reinforced sodaborosilicate glass matrix composite are studied. An abrupt increase of the coefficient of thermal expansion is observed and is attributed to formation of crystobalite in the sodaborosilicate glass matrix. This thermal expansion behavior is discussed with special reference to the phase transformation of the crystobalite.     

Late season nitrogen fertilization of soybeans: effects on leaf senescence, yield and environment

Nitrogen demand from soybean seeds during seed filling is very high and has been proposed as the cause of nitrogen remobilization and leaf senescence. Previous research has not shown consistent effects of late season fertilization on seed yield, while its effects on leaf senescence have not been evaluated. Two field experiments were performed to determine the effects of a late season N fertilization on leaf senescence and fall, seed yield and its components, and residual soil nitrate, and to evaluate the potential risk of groundwater contamination. Two rates of nitrogen (50 and 100 kg N ha^–1) were applied at the R3 and R5 development stages. Nitrogen fertilization, either at R3 or R5, increased soil nitrate availability during the seed-filling period. Seed yield, seed number and protein content were not affected by N fertilization. The addition of 100 kg N ha^–1 produced a small delay of 1–2 days in the leaf fall, and slightly increased seed size (3.6%). Our results suggest that increasing soil N availability during the seed-filling period is not an effective way to delay leaf senescence or to increase seed growth and yield of soybean. Nitrogen fertilization increased the level of residual nitrate in the top soil at one site (the one with lowest seed yield), increasing the risk of nitrate leaching during subsequent fallow.     

阳离子型偶联表面活性剂改性硝酸铵性能研究

对阳离子型偶联表面活性剂膨化处理的改性硝酸铵进行了电镜扫描、孔径与孔容分布、粒径分布、比表面积、抗吸湿结块性及爆炸性能的实验研究，结果表明：同普通硝酸铵相比，阳离子型偶联改性硝酸铵的晶形不规则，富含气孔；比表面积大，可达3869．56cm^2／g；95％有效孔径处于介孔范围，有较小的粒径范围，主要分布在10～1000μm范围内；并且有良好的抗吸湿结块性，改性硝酸铵的吸湿率比普通硝酸铵的吸湿率降低约60％，抗压破坏力仅为普通硝酸铵的1／6，用其制得的粉状工业炸药具有更好的物理性能和爆炸性能。     

含防爆剂农用硝酸铵的感度研究

实验在169℃左右加热硝酸铵到熔融状态,加入防爆剂,冷却到室温,得到含防爆剂的硝酸铵。测试其摩擦感度、5 s延滞期爆发点、静电火花感度以及配成铵油炸药后的撞击感度、雷管感度。结果表明,含防爆剂硝酸铵较普通硝酸铵撞击感度从88%降到24%,摩擦感度降为0%,5 s爆发延滞期从462℃增加到474℃,静电火花感度和雷管感度无明显变化。     

氟树脂涂料中氟含量测定方法的探讨

讨论了以氧气瓶燃烧法分解氟树脂,把氟树脂中的氟转化为氟离子,然后以硝酸镧标准溶液进行滴定,从而测定出氟树脂中的氟含量,再根据定量关系计算出氟树脂涂料中的氟含量的方法。该方法简单易行,准确可靠,省时省力。     

硝酸铈铵复盐制备工艺研究

对硝酸铈铵复盐的制备工艺进行了研究。分析了反应物的加入量、反应温度、反应时间以及其它工艺条件对制备硝酸铈铵复盐产品质量的影响。得出了制备分析纯硝酸铈铵复盐的方法。该方法可获得纯度达99%以上的橘红色硝酸铈铵复盐,收率达85%以上。     

Foliar fertilization of high-yielding peanuts during the pod-filling period

A 2-year field experiment was carried out in a sandy soil (Xeropsament-Torripsament) at Nir Yizhaq, Israel, where commercially grown peanut plants were sprayed with different NPKS solutions during the pod-filling period. All foliar sprays were applied in addition to the fertilizer which had been added to the soil before planting. The differences in yield between the treatments were not significant in either year. In the first year, there was a tendency toward increased yields of pods (up to 13%) and of hay (up to 16%) when four foliar fertilizer applications (10 kg N, 1 kg P, 3 kg K and 0.5 kg S/ha/application) were given, at one-week intervals. N was added mainly as urea, P and K as potassium polyphosphate, and S as ammonium sulphate. In the second year, the highest yield was obtained in the control plots and the differences between the treatments were not significant. Utilization of foliar nutrient application seems to be dependent upon availability of these nutrients in the soil.Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No. 1976-E. 1087 series.