宜昌市磷石膏综合利用对策探讨

文章针对宜昌市磷化工发展现状和磷石膏处理处置中存在的环境问题,分析了磷石膏的基本特性及危害,从技术、市场、经济和政策等方面分析了磷石膏利用过程中存在的一些制约因素,并对宜昌市磷石膏综合利用提出了一些探讨性的建议和对策。     

黄淮平原农田土壤中重金属的分布和来源

对黄淮平原224个农田表层土壤样品中7种重金属(As、Cd、Cr、Hg、Ni、Pb和Zn)浓度进行了调查,采用Hakanson潜在生态危害指数法对其生态危害进行了评价,并用相关性、逐步回归和主成分分析对重金属来源进行了解析.结果表明,农田土壤中7种重金属的平均浓度分别为11.8、0.17、79.0、0.04、35.3、25.3和73.8 mg·kg-1.与黄淮平原的土壤背景值相比,调查区域农田土壤重金属污染处于低污染水平,这与重金属污染指数评价的结果一致.重金属的潜在生态危害评价结果显示,除Cd和Hg的污染存在中等潜在生态危害风险外,其他重金属的潜在生态危害轻微.相关性分析和主成分分析结果表明,黄淮平原的农田土壤中Cr、Ni和Zn主要来自于工业烟尘沉降和化石燃料燃烧排放,As、Cd和Pb主要来自于污水灌溉,磷肥和有机肥的大量施用,而Hg可能来自于母质淋溶.     

Exploring of toxic Pb(II) removal by low-cost bio-adsorbent of camphor leaf forestry waste after camphor oil extraction

Environmental Science and Pollution Research - Camphor leaf (CL) was widely used to extract camphor oil and thus led to abundant forestry waste. In order to reduce pollution, the waste CL was used...     

铁氧化物/壳聚糖复合纳米纤维的制备及吸附五价砷研究

采用高压静电纺丝方法,制备了新型铁氧化物/壳聚糖复合纳米纤维砷吸附剂.扫描电子显微镜(SEM)观察结果显示,该纳米纤维的平均直径为(158±24)nm.X射线衍射谱图(XRD)表明,该纳米纤维为无定形结构.所制备的吸附剂在弱酸性或中性条件下对砷吸附率大于93%;吸附速率快,100 min内可达到吸附平衡;吸附剂对低浓度砷有很强的吸附亲和力,可将初始浓度为750μg·L-1的砷降低到10μg·L-1以下的安全饮用水水平;中性条件下吸附砷的最大容量为7.1 mg·g-1,吸附等温线符合Freundlich模型;有机质对吸附的影响较小;吸附剂可用低浓度Na OH洗脱再生.研究结果表明,该吸附剂制备方法简单,易分离再生,在饮用水除砷领域有较好的应用前景.     

Deriving sorption indices for the prediction of potential phosphorus loss from calcareous soils

The aim of this study was to develop techniques to evaluate soil phosphorus (P) sorption capacity (PSC) and determine critical soil P levels to predict P loss potential for calcareous soils. Seventy-five soils mostly from Northern China were analyzed for soil P using four extraction methods (water, P_w; carbonate, P_Ols; ammonium oxalate, P_ox; and Mehlich 3, P_M3) as well as PSC derived from single-point (PSC₁₅₀) and multipoint sorption (S _t) isotherms. Strong correlation was found between PSC₁₅₀ and S _t (r ²=0.89, p<0.001). The sum of αCa_M3 and βMg_M3 as an index of PSC (PSC_{(CaM3 + MgM3)}) was most closely related to the maximum amount of P sorbed (S _max) as given by the sum of S _t and soil initial P setting α=0.039 and β=0.462 (r ²=0.80, p<0.001). The degree of P saturation (DPS) was thereafter calculated from PSC_{(CaM3 + MgM3)} (DPS_{(CaM3 + MgM3)}), to which Olsen P (P_Ols) was significantly correlated (r ²=0.82, p<0.001). In a split-line regression from P_w against DPS_{(CaM3 + MgM3)} (r ²=0.87, p<0.05), a change point was identified at 28.1% DPS_{(CaM3 + MgM3)}, which was equivalent to 49.2 mg kg^?1 P_Ols and corresponded to a P_w concentration of 8.8 mg kg^?1. After the change point, a sharp increase in P_w was observed. Our results reveal a new approach to approximating DPS from Ca_M3 and Mg_M3 for calcareous soils without the need to generate a S _max. We conclude that in the absence of an environmental soil test criteria for P, the DPS_{(CaM3 + MgM3)} and P_Ols could be used to predict P loss potential from calcareous soils.     

苏云金芽孢杆菌抗东亚飞蝗(Locusta migratoria manilensis)的活性

采用毒力生物测定的方法,测定了600株从我国各地土壤和死虫等样品中分离的苏云金芽孢杆菌对东亚飞蝗的毒力.这些菌株几乎分布于已知的70个H血清型.在600株苏云金芽孢杆菌中,有560株(占93.4%)对东亚飞蝗无毒(死亡率小于20%),只有3株(占0.5%)对东亚飞蝗有较高毒性(死亡率大于70%).同时对筛选出的特异性菌株的杀虫活性进行了进一步研究.图2表2参8     

从TM图像自动提取洪涝灾情的研究

1991年夏我国江淮地区发生特大洪涝灾害,本文报道应用TM图像提取洪涝灾情信息的试验研究结果,发展了一套从TM图像数值分析入手,把TM包含的丰富光谱信息转化为洪涝灾情信息的图像应用处理技术.计算机自动输出的滁河和水阳江两流域洪涝灾情分布图和面积数据经实地验证准确可信.     

Distribution of rare earth elements in PM10 emitted from burning coals and soil-mixed coal briquettes

Emission from burning coals is one of the major sources of the airborne particles in China. We carried out a study on the rare earth elements (REEs) in the inhalable particulate matter (PM₁₀) emitted from burning coals and soil-coal honeycomb briquettes with different volatile contents and ash yields in a combustion-dilution system. Gravimetric analysis indicates that the equivalent mass concentration of the PM₁₀ emitted from burning the coals is higher than that emitted from burning the briquettes. The ICP-MS analysis indicates that the contents of total REEs in the coal-burning PM₁₀ are lower than those in the briquette-burning PM₁₀. In addition, the contents of the light rare earth elements (LREEs) are higher than those of the heavy rare earth elements (HREEs) in the PM₁₀ emitted from burning the coals and briquettes, demonstrating that the REEs in both the coal-burning and briquette-burning PM₁₀ are dominated by LREEs. The higher contents of total REEs and LREEs in the coal-burning PM₁₀ are associated with the higher ash yields and lower volatile contents in the raw coals. A comparative analysis indicates that the La/Sm ratios in the PM₁₀ emitted from burning the coals and briquettes, being lower than 2, are lower than those in the particles from gasoline-powered vehicle emission.     

宜昌市饮用水源地保护问题及对策

“十一五”全国主要污染物排放总量减少10％已成为约束性指标。面对严峻的形势,尽管社会各界空前重视,但各地减排工作进展不平衡,仍存在经济增长方式仍然粗放、政策措施落实不到位等问题。针对存在问题,提出了加大产业结构调整力度、污染防治资金投入、实施严格的环境准入制度等政策措施,完善减排体系、适时修改国家污染减排核算细则等技术措施,加大环境执法和环境监管力度、减排宣传力度等保障措施。     

遵化地质灾害发育特征及其防治措施

为了查明遵化市地质灾害分布规律和发生机制,通过野外实际调查和搜集相关资料等方法,对辖区内各种地质灾害进行了细致的分析和研究,阐述了产生地质灾害的地质条件和诱发因素,并对今后地质灾害的发展趋势做了可靠性的预测,对地质灾害防治提出建设性意见。遵化市地质灾害以地面塌陷和泥石流危害最大,其防治措施应以预防为主,加强监管力度,并积极做好工程防治工作。