中国5种土壤跳虫对重金属镍的毒性响应

为了研究镍(Ni~(2+))对不同种类跳虫的毒性效应,将曲毛裸长(Sinella curviseta)、四刺泡角(Ceratophysella duplicispinosa)、小原等节(Proisotoma minuta)、茉莉花长角(Entomobrya sp.)、符氏直棘(Orthonychiurus folsomi)5种中国优势跳虫物种,在琼脂培养基环境下分别暴露于Ni~(2+)的8个浓度组中进行24 h、72 h-LC_(50)急性毒性试验和28 d生存试验。利用Bliss法测得其5种跳虫的24 h-LC_(50)分别为52.99、35.91、33.46、23.72、13.50 g·L~(-1);72 h-LC_(50)为46.25、4.54、13.37、14.79、4.35 g·L~(-1)。在28d生存试验中得到成虫存活数量和繁殖情况。结果表明,5种跳虫中曲毛裸长对镍有较强的耐受性,茉莉花长角和小原等节次之,四刺泡角和符氏直棘较弱。符氏直棘与四刺泡角相比,随时间增加对镍的耐受性有相对增强的趋势。此外,Ni~(2+)对跳虫的毒性影响表现出阶段性的阈值效应。Ni~(2+)对5种跳虫的繁殖均有抑制作用。     

有机氯农药硫丹的生殖毒性及其机制研究进展

硫丹作为一种广谱有机氯农药,在农业区域周边的土壤和水体中都存在较高残留,2011年被斯德哥尔摩公约列入持久性有机污染物(POPs)名单。硫丹已被证实对神经系统、心血管系统、肝、肾等具有毒性作用,关于其生殖毒性的研究很多,但潜在机制尚不完全清楚。本文总结了硫丹导致的不同动物的生殖毒性,并从生殖器官和生殖细胞损伤、氧化应激以及DNA损伤、生殖细胞周期阻滞及细胞凋亡等方面,对近年来硫丹生殖毒性及其作用机制研究进展进行综述,并对其中存在的问题进行讨论,以期有助于深入了解硫丹的毒性效应。     

煤矸石制备Sialon材料影响因素研究

煤矸石还原氮化法制备Sialon材料的影响因素很多,主要有原料组成、反应温度和保温时间、添加剂的种类和用量、N2的流量和压强以及原料的粒度等.结合实验研究,分析了部分因素对制备Sialon材料的影响.     

“混凝气浮-膜生物反应器”处理林化废水工程运行调试研究

本文中根据林化废水特征确定使用"混凝气浮-膜生物反应处理器"的工艺进行处理。工程中硫酸铝的投加量为40mg/L,PAM的投加量为3mg/L,在废水pH值为7～8时进水COD、SS、OIL为279mg/L、20mg/L、26mg/L,进行混凝气浮后,出水的COD、SS、OIL浓度依次为135mg/L、9.6mg/L、9.5mg/L,去除率分别达到了52%、50%、64%。膜生物反应系统的调试,以污泥接种的方式进行污泥培养驯化。初期以面粉作为营养源清水培养污泥,按照7天左右的周期按每次30m3/d的污水进水量逐渐增加污水的比例,直到完全进水,调试驯化期污泥浓度控制在2500～3000mg/L。正常运转中污泥浓度可达到5000mg/L左右,出水水质COD、SS、OIL浓度分别达到30mg/L、6mg/L、3mg/L,符合处理目标要求。     

含铜废催化剂中铜的回收

采用热解—氨浸工艺处理含铜废催化剂（w（Cu）为23.6%）,优化了工艺条件,并通过蒸氨还原法制备出Cu₂O产品。实验结果表明：热解工段中,控制管式热解炉的空气流量为3.0 m³/min,在升温速率20 ℃/min、热解终温600 ℃、终温保持时间90 min的优化条件下,含铜废催化剂中的有机物热解完全;氨浸工段中,以NH₄Cl-NH₃-H₂O溶液为氨浸液,控制氨浸温度为40 ℃,在烧成料研磨时间90 min（粒径29.43 μm）、氨浸液总氨浓度4 mol/L、氨浸时间80 min的优化条件下,铜浸出率达到98%;经蒸氨还原法制得的Cu₂O产品的质量符合HG/T 2961—2010《工业氧化亚铜》中的一等品标准,产率为24%。     

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.     

Translocation analysis and safety assessment in two water spinach cultivars with distinctive shoot Cd and Pb concentrations

A pot experiment was conducted to investigate the translocation of cadmium (Cd) and lead (Pb) and assess the safety of edible parts in two cultivars of water spinach (Ipomoea aquatica Forsk.) contrasting in shoot Cd and Pb concentrations. A low-Cd-Pb cultivar (QLQ) and a high-Cd-Pb cultivar (T308) were grown in five soils with different concentrations of Cd and Pb. The results showed that QLQ had lower Cd and Pb concentrations in stems and leaves and higher root Cd concentration than T308 did. Root Pb concentration of T308 dramatically increased with increasing soil Pb concentration and was higher than that of QLQ in the highest Pb treatment. The root-to-stem Cd translocation ability in T308 was 2.3–3.0-fold higher than that in QLQ. Nevertheless, there was no significant difference in root-to-stem Pb translocation between QLQ and T308. The bioconcentration factors (BCFs) for Cd and Pb in the two cultivars remained stable in different Cd or Pb treatments, which were attributable to the homeostatic control mechanisms of Cd and Pb in water spinach.     

跌水曝气沸石床工艺预处理生活污水

简述了采用跌水曝气沸石床工艺预处理生活污水的处理效果。实验结果表明,跌水高度分别为0.3、0.45和0.60 m 3种情况下,原水经跌水曝气后,溶解氧的增加值平均为2.4、3.6和4.2 mg/L。水力停留时间平均为2 h情况下,进水COD、TN和TP分别在309-464、33～95和4.0～7.5 mg/L范围变化时,相应平均去除效率分别为47.25%、46.39%和40.75%。     

热处理对脱水污泥溶解特性及厌氧消化性能的影响

分别对脱水污泥在100、130和170℃条件下进行热处理,研究热处理对脱水污泥溶解特性的影响。此外,在半连续式完全混合反应器中进行厌氧消化实验研究不同热处理污泥的厌氧消化性能。实验结果表明,在100、130和170℃条件下,污泥COD溶解率由处理前的5.23%分别提高至20.08%、22.50%和27.20%,脱水污泥热处理规律和效果与高含水率污泥(总固体含量<5%)基本一致。经130℃2 h和170℃30 min高温热处理后污泥甲烷产率显著提高,较原泥分别提高24.64%和38.61%,沼气中甲烷含量稍有降低。     

锑矿区土壤重金属污染及优势植物对重金属的富集特征

通过野外调查采样,分析了冷水江锑矿区4个采样点土壤和优势植物中重金属含量,以及矿区生长的5种优势植物对Sb、As、Cd、Pb、Cu和Zn的的吸收与富集能力及其富集特性。结果表明,矿区土壤中6种重金属元素的平均含量均超出湖南省土壤背景值和全国土壤背景值,土壤受Sb污染最严重,其次是Cd、As的污染。5种优势植物淡竹叶、苎麻、芒草、狗尾草和白背叶体内Sb、As的含量都超过正常范围,具有修复矿区土壤Sb、As污染的潜力。其中苎麻对Sb的富集系数和转运系数均大于1,满足Sb超富集植物的基本特征,可作为生态恢复的先锋植物;芒草对Cd的富集系数和转运系数都大于1,对重金属有较强的耐性,作为重金属污染的修复植物具有较好的应用前景。