膨润土综合利用新工艺

提出了以膨润土为原料制取水玻璃和铵明矾的新方法 ,研究了主要工序的最佳工艺条件。在最佳工艺条件下 ,膨润土中铝的浸出率在 96 %以上 ,酸浸滤饼中活性二氧化硅的浸出率在 97%以上 ,制得的水玻璃和铵明矾质量符合国家标准。     

氯化铵分解氟碳铈矿回收稀土的研究

提出氯化铵焙烧法提取氟碳矿中稀土新的工艺路线,考究反应温度、,时间、氯化铵用量及固氟添加剂对稀土回收的影响,在焙烧温度５００℃,焙烧时间１小时,氯化铵／矿重＝０．５及固氟添加剂存在的条件下,稀土回收率达到８４％,同时氯化铵焙烧法对铁的氯化具有选择性,焙砂热水浸出得到的浸取液,铁的含量很低,因此采用该法分解氟碳铈矿更有利于后续过程的稀土净化。     

磷酸盐激光玻璃中铂颗粒密度与氧化还原平衡关系的研究

用吸收光谱法研究了Ｒ２Ｏ—ＢａＯ—Ｐ２Ｏ５系统磷酸盐激光玻璃中铂颗粒密度与铭的氧化还原平衡的关系。结果表明，玻璃中铂颗粒密度随平衡向右移动而减小；玻璃中平衡随熔炼气氛中氧分压增大、熔炼温度升高而向右移动，当足够大时，铂颗粒不能形成。     

Remediation of oil spill polluted water from Niger Delta Nigeria by sorption onto ammonium sulfate modified Dialium guineense seed husk

The abstraction of crude oil molecules from aqueous solution (produced water) and from real petroleum polluted water (collected from River State, Nigeria) by Dialium guineense Seed Husk (DGSH) and its ammonium sulfate functionalized form (AS-DGSH) was studied using a batch technique. The sorbents were characterized using Fourier transform infrared (FTIR), BET surface area analysis and the Scanning electron microscopy (SEM). Crude oil characterization revealed a light crude oil based on the API gravity of 35.6⁰. The Langmuir and Freundlich models gave good fits for crude oil sorption on DGSH and AS-DGSH respectively. The sorbents were found to remove over 50% of crude oil from the real polluted water at the natural pH of 6.1 and showed increase in removal with increase in sorbent dose. The potential of DGSH and its ammonium sulfate modified derivative as effective low cost sorbents for oil spill treatment was established.     

Agronomical evaluation of phosphate fertilizer as a nutrient source of phosphorus for crops: Isotopic procedure

The agronomic effectiveness of P fertilizers, as sources of phosphorus for crops, was evaluated using the quantities, P_f, of phosphorus taken up byLolium perenne grown on 14 soils during greenhouse experiments in pot cultures. The P_f quantities were determined using³²P-labelled fertilizers. Data were analysed using a new concept: the Isotopic Relative Agronomic Effectiveness (IRAE). The IRAE value was defined as the ratio of the P_f quantity, taken up by a crop, of a tested fertilizer over the P_f quantity, taken up by a crop, of a fertilizer used as standard. In our experiments diammonium phosphate (DAP) was used as standard P fertilizer and two rock phosphates, the North Carolina rock phosphate (NCPR) and a calcium-iron-aluminium phosphate (Phospal), were tested. As a linear relationship between P_f(NCPR) quantities and P_f(DAP) quantities was obtained, with r² = 0.95, when the application rates increased from 15 mgP (kg soil)^–1 to 200 mgP (kg soil)^–1, it is conciuded that IRAE values for a given fertilizer, other than the standard fertilizer, could be determined with a single rate of application. As regards soil pH in the range 4.7 to 8.2 the IRAE_NCPR is related to soil pH by a curvilinear relationship: log IRAE_NCPR = –(0.44) pH + 4.05 with r² = 0.89. The average of IRAE_phospal values was 0.15 with a standard error = 7% irrespective of soil pH. Then a logarithmic relationship was obtained between IRAE values of the two tested fertilizers and their water P-solubility determined at the soil pH where they were applied.     

The determination of phosphate availability for some less conventional phosphate fertilisers

More than in the case of the other major fertiliser elements the performance of phosphorus in fertilisers in dependent on the state of chemical combination of the element. As distinct from typical American practice where fully acidulated fertilisers are emphasised, some other countries have moved in part to production of materials of less than full acidulation where some reliance is placed on the reactivity of the original phosphate rock. Solutions of various aliphatic acids and their salts have been used as tests for the availability of phosphorus in fully acidulated fertilisers and, to a degree, for phosphate rocks themselves. Less than fully acidulated products are at present assessed in the same way as fully acidulated materials, but in this and other evaluations problems and anomalies arise which are discussed within the framework of a number of fertiliser systems. Analytical data are adduced which illustrate the effects of some extraneous cations on the results achieved which conflict with some previous opinions. Research towards a fuller understanding of the subject is suggested.     

Ingestion of tall larkspur by cattle

Tall larkspur (Delphinium spp.) is a palatable but toxic poisonous plant in the western United States. The toxins in tall larkspur are diterpenoid alkaloids. We examined the influences of food flavor and postingestive consequences on consumption of a 33% larkspur pellet during 30-min feeding periods for five days using esophageally fistulated cattle that were sham-fed larkspur pellets. Consumption by the sham-fed group was compared to a control group fed alfalfa pellets, and a larkspur group fed only larkspur pellets. Sham-fed cattle did not decrease (P > 0.1) feed consumption compared to controls, indicating no significant difference in food flavor. The larkspur group decreased (P < 0.05) feed consumption by 41% relative to controls and by 31% relative to sham-fed animals (P = 0.08). This reduction in feed consumption indicates the adverse postingestive consequences of tall larkspur ingestion, as the larkspur group apparently developed a conditioned taste aversion to the larkspur pellet. Even though these animals were averted to the pellets, they showed none of the classical signs of intoxication from ingestion of tall larkspur.This research was supported in part by the Utah Agricultural Experiment Station, Utah State University, Logan, Utah 84322. Approved as journal article No. 3846.     

A discussion of the methods for comparing the relative effectiveness of phosphate fertilizers varying in solubility

Because various phosphate (P) fertilizers differ widely in their solubility, it is commonly observed that crop response to P fertilizers varies under the same soil and crop conditions. Furthermore, a major problem encountered in the methods for determining the relative effectiveness (RE) of water-insoluble P fertilizer (e.g., phosphate rock) with respect to water-soluble P fertilizers, e.g., single superphosphate (SSP) and triple superphosphate (TSP), is that their growth response curves are usually nonlinear and often do not share a common maximum yield. In this paper, we review and discuss the advantages and disadvantages of the three most commonly used methods for calculating the RE of phosphate rock with respect to TSP (or SSP). The three methods are vertical comparison, horizontal (substitution rate) comparison, and linear-response comparison.     

铜的萃取动力学研究

本文用氯化三烷基甲铵(N_(263))—煤油体系作为有机相进行了从碱性氰化液中萃取铜的动力学研究。实验是在一恒界面池(Lewis cell)中进行的。实验结果表明:铜的萃取速率与两相的搅拌强度几乎无关;但正比于两相的接触界面积及萃取剂浓度;萃取反应过程的表观活化能为18.750kJ/mol。对系统进行理论分析的结果可知,铜的萃取反应过程为反应与扩散在水膜内并列进行的过程,其主要特征表现为包含水膜的界面反应。通过数据处理,建立了如下萃取动力学模型:用此模型计算所得结果与实验结果的平均偏差为4.9％。     

A comparison of methods for measuring the effect of level of application on the relative effectiveness of two fertilizers

The effectiveness of a slowly soluble source of phosphate relative to a soluble source may decrease with increasing levels of application. This may cause yields to approach a lower asymptote. Four methods for measuring this effect are compared using field experiments in which a calcined rock phosphate (Calciphos) was compared with superphosphate for growth of subterranean clover. The methods were: subjective estimates using a hand drawn calibration curve; objective estimates using a fitted calibration curve; objective estimates using the fit of separate response curves; and objective estimates from the fit of a common response surface in which relative effectiveness was related to level of application. The role of these four methods differs. The first method, though often informative, is suitable only for an initial inspection of the data. The other three methods may all be useful for analysis but the fourth method was the most general. It gave the most sensitive statistical test and had the further advantage that it was a direct test of the hypothesis. All four methods showed that the relative effectiveness of Calciphos decreased with increasing levels of application.