硅藻土复合净水剂处理印染废水

用活化后的硅藻土配制成的复合净水剂，处理印染废水，具有脱色效果好、COD去除率高等特点，且费用低廉，不产生二次污染。||关键词##4硅藻土;;复合净水剂;;印染废水     

腐殖酸与稀土元素的作用及体系稳定性

 用稀土元素（La³⁺，Ce³⁺，Ho³⁺，Yb³⁺）标准溶液对湖泊沉积物腐殖酸进行非连续滴定，研究二者之间的络合反应能力及其结合产物在水溶液体系的稳定性。结果表明，腐殖酸结构中的活性点位在与三价稀土离子作用时表现出两种不同类型，在机制上采取两级络合反应。体系中沉淀生成与否主要取决于腐殖酸对稀土离子的容纳能力。     

富里酸对小麦植株积累稀土元素的影响

从我国东北黑土中提取和纯化富里酸。采用水培方法研究了富里酸对小麦植株生物积累稀土元素（La^3 ，Ce^3 ,Sm^3 ,Gd^3 ,Y^3 )的影响。结果表明，在所试验的多种浓度中，当富里酸浓度低于0.26mg(C)/L时，小麦积累稀土元素受到促进；而当富里酸浓度大于0.65mg(C)/L时，稀土元素在小麦植株中的积累受到抑制；富里酸对小麦积累稀土“高抑低促”的分界浓度介于0.26——0.65mg(C)/L之间。生长动态实验表明，小麦在含有2.0mg/L稀土和两种浓度（0.13和1.30mg(C)/L)的富里酸的营养液中生长，根部对稀土的积累呈线性增长规律（相关系数大于0.86)，茎叶部对稀土的积累无线性增长规律，小麦根部对稀土的积累远高于茎叶部，同样观察到富里酸对小麦积累稀土存在“高抑低促”的生物效应。     

红壤中镧积累对水稻的生理生态效应

通过盆栽试验 ,研究了红壤中稀土元素镧对水稻的生长发育 ,产量和一些对环境敏感的生理生化指标的影响 .结果表明 ,La浓度为 75mg·kg-1时水稻的生育期明显滞后 ,La浓度为 30 0mg·kg-1时水稻的生长显著受到抑制 ,产量显著降低 ,水稻生物量降低一半的EC50 =32 3 0 2mg·kg-1.La浓度为 75mg·kg-1时水稻的叶绿素a b显著降低 ,POD活性、细胞质膜透性和游离脯氨酸含量显著增高 .     

卫星地球站电磁环境的影响预测

对某卫星地球站划定近场，远场后，对近场内最大功率密度，远场轴向功率密度，近场地面功率密度作了预测，对天线轴向前方建筑物高度作了特别考虑，结果表明：近场内最大功率密度为629uw/m2，是GB8702－88《电磁辐射防护规定》职业照射导出限值的1．5倍，远场轴向3400米后，功率密度降到GB8702－88规定的公众照射导出限值的1／5以下；天线对地面的辐射环境影响较小，但轴向前方建筑物必须实行限高保护。     

Rare earth elements distribution in seawater and suspended particulate of the Central Mediterranean Sea

Rare earth element (REE) content in suspended and dissolved phases from the Strait of Sicily (Central Mediterranean Sea) has been measured. Vertical profiles of several dissolved REEs along the water column reflect the 3-D oceanographic features of the studied area and identifies the different water masses present there. Shale-normalized REE distribution patterns and derived parameters calculated for the suspended particulate show different atmospheric dust-surface inputs and their interactions with seawater. Finally, combined information from [La/Yb]_N, ratios, REE/La ratios and Eu anomalies measured in the suspended particulate suggest an important contribution of volcanic materials from the Etna volcano and Saharan dust to the lithogenic fraction of the suspended particulate.     

Environmental biogeochemical behaviors of rare earth elements in soil–plant systems

With the continual increase in the utilization of rare earth elements (REEs) for industrial and agricultural purposes in China, the research into the environmental biogeochemical behavior of REEs has become a pressing issue. The REEs’ content in soil and various parts of wheat under different conditions in soil–plant systems were measured by INAA and ICP-MS. The results showed four aspects. (1) The mean value of total REEs in soil of China was 176.8 mg kg⁻¹. The mean ratio of ΣLREE/ΣHREE in soils was 8.0 and cerium accounts for 42% of the total REEs. The content of REEs in wheat seed ranged between 10⁻¹¹ and 10⁻⁸ g g⁻¹, 3–4 orders of magnitude lower than that in soil. (2) The REEs contents in ryegrass, especially in roots, were significantly related to that of soil. The bioavailability of REEs in soil mainly depended on the exchangeable fraction of REEs, which was strongly affected by the physico–chemical properties of the soil. (3) Long-term foliage-dressing with Changle microfertilizer of REEs did not affect the contents and distribution patterns of REEs in soil. At the maturing stage of spring wheat, the REEs content was in the order of root > leaf >stem and crust. Compared with the control, foliage-dressing has a higher accumulation of REEs in root and leaf. However, no significant difference was found in stem and crust between the two treatments. (4) There was no significant accumulation with the soil-dressing method. When comparing controls in both foliage- and soil-dressing methods, no distinct residue of REEs in grains was found.     

镧对微囊藻的生长效应及被富集的动力学研究

研究了稀土元素La3 对微囊藻生长效应及其被微囊藻富集的动力学过程 .结果表明 :当La3 的添加浓度小于 2mg·l- 1 时 ,对微囊藻的生长有促进作用 ,当La3 的添加浓度大于 2mg·l- 1 时 ,微囊藻的生长受到抑制 .La3 在微囊藻中富集的动力学过程可用表面配位模型表征     

柳州地区各种红壤土种的酸沉降临界负荷研究

应用简单质量平衡法，多层模型ＰＲＯＦＩＬＥ和基于植物响应标准计算柳州红壤和土种的酸沉降临界负荷，并建立了系统完整地收集，测量与估算模型所需参数的方法。结果表明，柳州红壤各土种的硫沉降临界负荷为０．５０－１．８０ｋｅｑ．ｈｍ＾－２．ａ＾－１，为保护９５％的土壤不受酸沉降危害，柳州土壤的潜在酸度，酸度和硫沉降临界负荷分别为１．８ｋｅｑ；ｈｍ＾－２．ａ＾－１，１．９ｋｅｑ．ｈｍ＾－２．ａ＾－１和０．７０