聚合硅酸硫酸铝溶液中铝的形态分布及转化规律

以硫酸铝、水玻璃和铝酸钠为原料合成出了具有不同碱化度(B)和si／Al摩尔比的聚合硅酸硫酸铝(PASS)混凝剂,用Al-Ferron逐时络合比色法和^27Al NMR法研究了PASS中铝的形态分布．结果表明,Si／Al摩尔比对PASS形态的影响要小于B值的影响;在一定的B值和Si/Al摩尔比下,Alb成为PASS中铝的优势形态;PASS中Alb和Ferron试剂的反应遵循准一级反应规律,其Kb差异不大．     

水污染事故中半挥发性有机物应急监测方法研究

建立了车载式气相色谱/质谱联用仪(GC/MS)结合固相微萃取(SPME)前处理技术测定水体中半挥发性有机物(SVOCs)的方法,优化了萃取头类型、萃取温度与萃取时间、离子强度、解吸温度与解吸时间、搅拌速度等影响萃取效率的因素,以及仪器分析条件.24种SVOCs、7种OPPs和17种OCPs在1.00 μg/L～40.0 μg/L范围内线性良好,检出限为0.11 μg/L～0.39 μg/L,空白加标水样平行测定的RSD≤14.3％,回收率为51.0％～98.5％.     

Sulfate-reducing bacterial community shifts in response to acid mine drainage in the sediment of the Hengshi watershed,South China

Environmental Science and Pollution Research - Sulfate-reducing bacteria (SRB) are an attractive option for treating acid mine drainage (AMD) and are considered to be of great significance in the...     

Selenium protects against cadmium-induced kidney apoptosis in chickens by activating the PI3K/AKT/Bcl-2 signaling pathway

Cadmium (Cd) is a toxic heavy metal that can induce apoptosis. Selenium (Se) is a necessary trace element and can antagonize the toxicity of many heavy metals, including Cd. PI3K/AKT/Bcl-2 is a key survival signaling pathway that regulates cellular defense system against oxidative injury as well as cell proliferation, survival, and apoptosis. The antagonistic effects of Se on Cd-induced toxicity have been reported. However, little is known about the effect of Se on Cd-induced apoptosis in chicken kidneys via the PI3K/AKT/Bcl-2 signaling pathway. In the present study, we fed chickens with Se, Cd, or both Se and Cd supplements, and after 90 days of treatment, we detected the related index. The results showed that the activity of inducible nitric oxide synthase (iNOS) and concentration of nitric oxide (NO) were increased; activities of the mitochondrial respiratory chain complexes (complexes I, II, and V) and ATPases (the Na⁺-K⁺-ATPase, the Mg²⁺-ATPase, and the Ca²⁺-ATPase) were decreased; expression of PI3K, AKT, and Bcl-2 were decreased; and expression of Bax, Bak, P53, Caspase-3, Caspase-9, and cytochrome c (Cyt c) were increased. Additionally, the results of the TUNEL assay showed that the number of apoptotic cells was increased in the Cd group. By contrast, there was a significant improvement of the correlation indicators and occurrence of apoptosis in the Se + Cd group compared to the Cd group. In conclusion, our results confirmed that Se had a positive effect on ameliorating Cd-induced apoptosis in chicken kidney tissue by activating the PI3K/AKT/Bcl-2 signaling pathway.     

Multimethod,multistate Bayesian hierarchical modeling approach for use in regional monitoring of wolves

In many cases, the first step in large‐carnivore management is to obtain objective, reliable, and cost‐effective estimates of population parameters through procedures that are reproducible over time. However, monitoring predators over large areas is difficult, and the data have a high level of uncertainty. We devised a practical multimethod and multistate modeling approach based on Bayesian hierarchical‐site‐occupancy models that combined multiple survey methods to estimate different population states for use in monitoring large predators at a regional scale. We used wolves (Canis lupus) as our model species and generated reliable estimates of the number of sites with wolf reproduction (presence of pups). We used 2 wolf data sets from Spain (Western Galicia in 2013 and Asturias in 2004) to test the approach. Based on howling surveys, the naïve estimation (i.e., estimate based only on observations) of the number of sites with reproduction was 9 and 25 sites in Western Galicia and Asturias, respectively. Our model showed 33.4 (SD 9.6) and 34.4 (3.9) sites with wolf reproduction, respectively. The number of occupied sites with wolf reproduction was 0.67 (SD 0.19) and 0.76 (0.11), respectively. This approach can be used to design more cost‐effective monitoring programs (i.e., to define the sampling effort needed per site). Our approach should inspire well‐coordinated surveys across multiple administrative borders and populations and lead to improved decision making for management of large carnivores on a landscape level. The use of this Bayesian framework provides a simple way to visualize the degree of uncertainty around population‐parameter estimates and thus provides managers and stakeholders an intuitive approach to interpreting monitoring results. Our approach can be widely applied to large spatial scales in wildlife monitoring where detection probabilities differ between population states and where several methods are being used to estimate different population parameters.     

Environmental characteristics and land-use pattern changes of the Old Huanghe River delta,eastern China,in the sixteenth to twentieth centuries

The interaction between human and land in estuarine–coastal areas has become a focus of the global change research. Since the sixteenth century, the Old Huanghe River delta has experienced rapid accretion, the formation of rich ecological resources and diverse land use pattern changes; such information, in combination with a large number of historical documents, provides a unique research area for revealing the processes for ecosystem–human changes. We use historical documents and adopt multidisciplinary methods, to identify the relationship between ecosystem changes and human activities, on the basis of spatial and temporal analysis, for in the Old Huanghe River delta region. The results indicate that, in the sixteenth to nineteenth centuries, the long-term monopolistic development pattern under the government leadership, which occupied large quantities of ecological resources, controlled the coastal salt industry and marsh land exploitation. However, along with the delta ecosystem change and population growth, the development pattern became gradually unsustainable, i.e., the salt industry migrated toward the north, while the farming activities migrated toward the south with enhanced intensity of marsh reclamation. The government monopoly collapsed in the late nineteenth century, which enlarged the independent development space for the local residents, which, to a large extent, improved the land-use efficiency and reduced the population pressure.     

大蒜提取物排铅效果的研究

利用大蒜提取物进行小鼠的排铅试验,同时与常规药物排铅进行对比,表明大蒜提取物对小鼠的铅中毒致死效应具有拮抗作用,增加小鼠的存活率;能有效地将慢性铅中毒小鼠机体组织中蓄积的铅排出体外;不但可以与常规排铅药物如依地酸二钠钙配合使用,降低药物的用量,减少副作用的程度,还可单独使用,且具无毒、无副作用等优点。     

改进型升流式固体反应器处理猪粪污新工艺研究

对传统升流式固体反应器（USR）进行改进,反应器内设置专用搅拌器,搅拌器间歇开启,在保留USR各项优势的前提下,使料液与厌氧微生物接触更充分,反应温度更均匀,提高产气率,同时还解决了传统USR的“结壳”问题,提高了反应器的传质效率、甲烷产气率和COD去除效果。进料含固量在12.1%时,水利停留时间为17 d,反应器最高容积负荷达到4.9 kg COD/(m³·d),产气速率为2.55 m³/(m³·d),产气率达到0.359 m³/kg干猪粪。     

三峡库区农业区非点源氦的平衡变化及其污染防治

针对三峡库区农业区非点源氮,建立氮平衡变化模型,并在此模型的基础上,计算三峡库区各县2001-2005年的氮平衡变化,然后汇总库区氮的输入、输出及平衡量.结果表明.库区农业区2001年氮的输人量为6.60×105t/a,输出量为1.18×105t/a,平衡世为5.42×105t/a.其中进入水体量为1.98×105 t/a;2005年全流域农业区氮的输人量为5.84 ×105,t/a,输出为1.23×105 t/a,平衡量为4.61 × 105t/a.其中进人水体量为1.75×105t/a;2001-2005年三峡库区农业区氮输入量变化为0.76×105t/a,输出量变化为0.05 × 105t/a,平衡量变化0.81×105t/a.其中进入水体氮变化昔为0.23×105t/a.研究表明,长寿区、石柱县、武隆县、江津市、丰都县、巴东县、宜昌县、兴山县和巴南区2001-2005年非点源氮进入水体量变化较大,为今后三峡库区农业区水体氮污染重点防治区,并提出了一些非点源氮污染防治对策与建议.     

己二酸和己二酸钠强化石灰石WFGD的对比研究

在湍球塔设备上进行了己二酸和己二酸钠强化石灰石WFGD的对比研究,考察了2种添加剂对脱硫过程的强化和缓冲作用,分析计算了2种添加剂对石灰石的利用率。实验结果表明,2种添加剂可以在较低浆液pH下维持较高脱硫率,并且2种添加剂均促进了CaCO₃的溶解,在相同条件下己二酸钠有更好的脱硫效果,而己二酸有更好的缓冲作用,且己二酸促进CaCO₃溶解的效果更显著。