次氯酸钠处理终冷水中氰化物硫化物的研究

以次氯酸钠为氧化剂,用正交实验研究了次氯酸钠处理终冷水中氰化物和硫化物,得出正交实验中各因素的主次关系及对除氰除硫的影响。研究结果表明,反应体系的pH是影响脱氰脱硫的重要因素。在最佳处理条件,即pH为10．0,反应温度为25℃,投氯量系数为1．4,反应时间为45min．能使氰化物的质量浓度降至0．267mg／L,脱氰率高达99．8％,硫化物的质量浓度降到0．387mg／L,脱硫率达92．0％,达到≤0．5mg／L的国家排放标准。文章还对工业化提出了一些设想。     

XK—1．5型除尘清洗两用机的研究、试验与应用

采用高压水和喷嘴的引射原理，使水射流通过喷嘴后高效雾化，达到降尘的目的，并主要沉降５μｍ以下对人体具有致命危害的呼吸性粉尘。当更换喷嘴后也可进行积上和物体的表面清洗。     

一起工伤事故的分析与预防

叙述了工作面减速机液力耦合器伤人经过 ,分析了事故各方面的原因 ,并制定了预防措施 ,具有普遍性和典型性。     

Factors influencing farmers’ decisions on nitrogen fertilizer application in the Liangzihu Lake basin,Central China

Overuse of nitrogen (N) fertilizers in agriculture activities has caused severe water pollution in China. The lack of data at producer level hampers decision makers in the development and implementation of efficient policies to curb excessive N-fertilizer use. In a survey of 300 farm households in the Liangzihu Lake basin, we identified factors associated with farmers’ decisions on N-fertilizer use and application rate. Household survey and multiple linear regression models indicate that the average application rate in the study region is 229 kg N ha^?1, which exceeds the recommended rate for maximum profit for cereal crops (maize, wheat, and rice) in China of 150–180 kg N ha^?1. High N-application rates are associated with low farmland productivity (coefficient = ?15.66, p = 0.02), a high share of off-farm income (coefficient = 27.14, p = 0.003), and a low education level of the household head (coefficient = ?10.83, p = 0.039). Neither physical infrastructure nor access to input markets appears to be related to N-application rates. It may be concluded that excessive use of N in agriculture of Central China is mainly a problem of insufficient awareness and high share of off-farm income.     

An insight into the drag effect of water,land, and energy on economic growth across space and time: the application of improved Solow growth model

Environmental Science and Pollution Research - Economies that depend on natural resources can experience a resource drag effect when economic growth is limited by constraints on the availability of...     

磺胺嘧啶对纯膜MBBR氨氧化性能及氨氧化菌群的影响

通过向NH₄⁺-N质量浓度为30 mg·L⁻¹的合成废水中投加不同剂量磺胺嘧啶(SDZ)(0、1、3、5、7和10 mg·L^–1),比较了SDZ浓度对一台60 L单级纯膜移动床生物膜反应器(pure MBBR)的氨氧化速率、amoA基因丰度和氨氧化细菌(AOB)种群结构的影响,揭示了磺胺嘧啶对纯膜MBBR系统中氨氧化作用的影响机制。结果表明：1~3 mg·L^–1的SDZ显著提升了纯膜MBBR系统的氨氧化速率(P<0.05),出水${\rm{NH}}_4^{+} $-N质量浓度可降低至(0.19±0.10) mg·L^–1;5~10 mg·L^–1的SDZ仍能促进${\rm{NH}}_4^{+} $-N去除,但氨氧化速率变化相对平缓。相比于氨氧化古菌(AOA),AOB为纯膜MBBR氨氧化的主导者,AOB amoA基因丰度是AOA amoA基因丰度的12.2~168.5倍。1~10 mg·L^–1的磺胺嘧啶暴露显著抑制了AOB amoA基因丰度(P<0.05),但能有效刺激AOA amoA基因丰度上调(P<0.05)。高通量测序结果表明,添加磺胺嘧啶改变了AOB的种群多样性及结构,且1~3 mg·L^–1的SDZ能显著促进AOB种群多样化和亚硝化螺菌属(Nitrosospira)生长(P<0.05)。SDZ对氮源的补充、对AOB与AOA丰度占比的改变、对微生物耐药性的促进以及对AOB种群结构的干扰是其影响纯膜MBBR氨氧化过程的主要机制。     

Treatment of fluorine-containing pharmaceutical wastewater by VUV/UV process

Environmental Science and Pollution Research - As an advanced oxidation process, vacuum ultraviolet/ultraviolet (VUV/UV) has been intensively studied for drinking water treatment, but assessment of...     

Occurrence,source apportionment,and carcinogenic risk assessment of polycyclic aromatic hydrocarbons in urban road dusts in Shanghai

Environmental Science and Pollution Research - Polycyclic aromatic hydrocarbons (PAHs), as a class of important environmental pollutants, have received considerable concern due to their widespread...     

Magnetic properties of biogenic selenium nanomaterials

Environmental Science and Pollution Research - Bioreduction of selenium oxyanions to elemental selenium is ubiquitous; elucidating the properties of this biogenic elemental selenium (BioSe) is thus...     

Removal of SO2 from smelting flue gas by using copper tailings with MnSO4: factors optimization by response surface methodology

Environmental Science and Pollution Research - The abatement of SO2 and the utilization of copper tailings are identified as two attention-attracting environmental issues in the copper smelter. In...