Carbonaceous matter and PBDEs on indoor/outdoor glass window surfaces in Guangzhou and Hong Kong,South China

Organic films, collected from indoor and outdoor window surfaces in Guangzhou and Hong Kong of South China, were analyzed to quantify their organic carbon (OC), elemental carbon (EC), and polybrominated diphenyl ethers (PBDEs) content. The highest concentrations of OC, EC, and BDE-209 were found in Guangzhou with values of 10 000 μg m^?2, 2200 μg m^?2, and 4000 ng m^?2, respectively, and the highest concentration of Σ₇PBDE (sum of BDE-28, -47, -99, -100, -153, -154 and -183) was found in Hong Kong with a value of 25 ng m^?2. In most cases, the concentrations of PBDEs were higher in the exterior films than those in the interior films with BDE-209 as the predominant congener in both cities, suggesting that PBDEs mainly come from ambient environment, and deca-BDE accounts for major PBDE consumption. The growth rates of organic film on window surfaces were fast at the beginning, and reached a consistent level afterwards. The evolution rates ranged from 2.6 to 11 nm day^?1 for “bulk film”, while from 0.06 to 0.92 nm day^?1 for “pure film”. The concentrations of PBDEs on the window surfaces did not increase with the growth time, suggesting that the window surface may provide a good place for photo-degradation of PBDEs.     

好氧膜-生物反应器中微滤膜选择的实验研究

用扫描电镜表面观察和全自动压汞仪测定了2种亲水化改性PVDF微滤膜的平均孔径、孔隙率等基本性能参数。对2种膜的纯水通量,及其平板膜组件在好氧膜生物反应器内污染过程进行分析。结果显示,2种膜污染过程均呈现先缓慢后快速的"二阶段"趋势,第二阶段是膜污染的主导阶段。尽管平均孔径小、孔隙率高的膜本身阻力大、纯水通量低,但其污染速率较低,物理及化学清洗恢复率较高。膜孔径及孔隙率指标是影响其在MBR中运行的污染速率的主要因素,平均孔径小、孔隙率高的膜抗污染能力强。     

镍网负载纳米TiO_2光催化反应器对酸性品红脱色效果实验研究

采用负载纳米TiO2的三维镍网装配了光催化反应器,就其对酸性品红溶液进行脱色效果进行了实验研究。考察了反应器的3种装配条件、品红初始浓度、pH值、H2O2投加量、紫外光剂量等因素对酸性品红脱色效果的影响。结果表明:UV灯+镍网+TiO2模式组合的反应器脱色效果最好;在相同的处理时间内酸性品红溶液的脱色率随起始浓度的增大而减小;将酸性品红溶液pH值调至5时脱色效果最明显,70 min的脱色率可高达94.8%。脱色效果还可以通过溶液中添加H2O2和控制紫外线剂量来调节。当溶液中H2O2投加量为0.5 g/L时,处理70 min后的脱色率可高达98.3%;到达反应界面紫外光剂量越多则能够获得越高的酸性品红脱色率。     

氧化/吸附/混凝协同工艺处理焦化废水生物处理出水的过程及效果分析

针对焦化废水生物处理出水中继续存在多种有机污染物而影响达标及存在安全隐患的现状,基于废水中有机物的物理化学特性,构建了氧化/吸附/混凝的深度处理过程。在NaC lO投加量为40 mg/L,AC投加量为500 mg/L,PFS投加量为300 mg/L,反应时间为0.5 h,以及pH为7.0的最佳条件下,先氧化后吸附混凝,该过程可以实现COD去除率为75%以上,色度去除率80%以上,处理后的水样其COD值与色度值分别下降到60 mg/L及20倍以下;通过GC/MS方法分析处理前后水样中的有机物组分,发现水样中大部分单环芳香族化合物和多环芳香族化合物,部分含氮杂环化学物、有机氯化物以及溴化物被去除,但是,长链烷烃和部分芳香烃继续保留。研究结果证明了氧化/吸附/混凝协同工艺的效果与焦化废水生物出水中有机污染物的分子结构、存在形态形成构效关系,催化作用与氧化作用的协同是获得高效去除率的关键。     

板框压滤机内酒精污泥过滤脱水特性

采用螺杆泵输送和板框过滤机压滤的方法对酒精污泥进行机械脱水,研究了絮凝剂(聚丙烯酰胺PAM)添加量、污泥的进口湿含量、螺杆泵转速、过滤介质和过滤时间对污泥过滤特性的影响,并对滤饼吹气压榨进一步脱水。实验表明,在PAM添加量wPAM=3 kg/(t干污泥),污泥的进口湿含量x0=95%,螺杆泵转速n=180 r/min,过滤时间t=2.5 h并进行吹气压榨可将污泥的湿含量降至69.91%。     

Cesium and strontium sorption by selected tropical and subtropical soils around nuclear facilities

The dynamics of Cs and Sr sorption by soils, especially in the subtropics and tropics, as influenced by soil components are not fully understood. The rates and capacities of Cs and Sr sorption by selected subtropical and tropical soils in Taiwan were investigated to facilitate our understanding of the transformation and dynamics of Cs and Sr in soils developed under highly weathering intensity. The Langmuir isotherms and kinetic rates of Cs and Sr sorption on the Ap1 and Bt1 horizons of the Long-Tan (Lt) and the A and Bt1 horizons of the Kuan-Shan (Kt), Mao-Lin (Tml) and Chi-Lo (Cl) soils were selected for this study. Air-dried soil (<2 mm) samples were reacted with of 7.5 × 10⁻⁵ to 1.88 × 10⁻³ M of CsCl (pH 4.0) or 1.14 × 10⁻⁴ to 2.85 × 10⁻³ M of SrCl₂ (pH 4.0) solutions at 25 °C. The sorption maximum capacity (q_m) of Cs by the Ap1 and Bt1 horizons of the Lt soil (62.24 and 70.70 mmol Cs kg⁻¹ soil) were significantly (p < 0.05) higher than those by the A and Bt1 horizons of the Kt and Cl soils (26.46 and 27.49 mmol Cs kg⁻¹ soil in Kt soil and 34.83 and 29.96 mmol Cs kg⁻¹ soil in Cl soil, respectively), however, the sorption maximum capacity values of the Lt and Tml soils did not show significant differences. The amounts of pyrophosphate extractable Fe (Fe_p) were correlated significantly with the Cs and Sr sorption capacities (for Cs sorption, r² = 0.97, p < 1.0 × 10⁻⁴; for Sr sorption, r² = 0.82, p < 2.0 × 10⁻³). The partition coefficient of radiocesium sorbed on soil showed the following order: Cl soil ? Kt soil > Tml soil > Lt soil. It was due to clay minerals. The second-order kinetic model was applied to the Cs and Sr sorption data. The rate constant of Cs or Sr sorption on the four soils was substantiality increased with increasing temperature. This is attributable to the availability of more energy for bond breaking and bond formation brought about by the higher temperatures. The rate constant of Cs sorption at 308 K was 1.39-2.09 times higher than that at 278 K in the four soils. The activation energy of Cs and Sr sorbed by the four soils ranged from 7.2 to 16.7 kJ mol⁻¹ and from 15.2 to 22.4 kJ mol⁻¹, respectively. Therefore, the limiting step of the Cs⁺ or Sr²⁺ sorption on the soils was diffusion-controlled processes. The reactive components, which are significantly correlated with the Langmuir sorption maxima of Cs and Sr by these soils, substantially influenced their kinetic rates of Cs and Sr sorption. The data indicate that among components of the subtropical and tropical soils studied, short-range ordered sesquioxides especially Al- and Fe-oxides complexed with organics play important roles in influencing their capacity and dynamics of Cs and Sr sorption.     

Carbon Budget for Basic Needs:Implications of International Equity and Sustainability

The fundamental way of satisfying the basic needs of human development is to secure the basic needs,limit luxurious and wasteful emissions,and ensure the fulfillment of climate targets,so as to achieve intra-and intergenerational equity.In this paper,the author discusses and analyzes a series of challenges that the development has to face,such as poverty elimination,urbanization,and industrialization,and the problems of increased consumption that is brought about by the improvement of living standards;the author distinguishes the stock emission,which does not need annual updating,and the flow emission of regular consumption;the author also defines the standards of energy consumption and carbon emissions that can meet the basic needs.On this basis,the author proposes the concept and method of carbon budget,compares this method with other means,and in particular,studies and analyzes the implications of international equity and sustainability of carbon budget as part of the international climate regime design.     

The Concept and Theoretical Implications of Carbon Emissions Rights Based on Individual Equity

Climate change has become a hot topic in international environmental negotiations.For post-Kyoto international climate regime negotiations,many countries have proposed a variety of frameworks to share the emission reduction responsibilities and allocate carbon emission rights,and have tried to quantify the emission reduction obligations of all countries based on the perspectives of international equity and individual equity.In this paper,the authors have distinguished the concepts of carbon emissions rights based on these two perspectives respectively,have analyzed the relationship between carbon emissions per capita and economic development,and have calculated and compared the proportion of cumulative emissions per capita of different countries in history and future,and then authors conclude that emission reduction obligations should be allocated based on each country’s conditions,including historical emissions,development stage,and future demands.Developed countries should take the initiative to significantly reduce their emissions because they have already accomplished their industrialization process.However,developing countries are still in the process of industrialization,which requires more emission rights to meet their development needs.For China,the concept of carbon emissions based on individual equity can be used as a theoretical tool for the allocating the international carbon emissions rights.     

Methane–benzene binary mixture destruction in a reverse flow catalytic reactor

An experimental study of methane–benzene binary mixture purification in a bench-scale reverse flow reactor is carried out. Results for catalytic oxidation of the two hydrocarbons with remarkably discrepant chemical properties show that autothermal catalytic combustion of very lean combustible concentration can be achieved with periodic feed reversal. Benzene is well removed, but methane conversion is relatively low and mainly determined by the thermal level of the reactor. If methane is added as auxiliary fuel to maintain autothermal operation when the volatile organic compound (VOC) concentration in the contaminated air is too low, an excess amount is needed. The influences of gas superficial velocity, cycle period, and methane-to-benzene ratio are discussed. A mathematical model is developed and solved using a FORTRAN code, with good correspondence being observed between the two approaches. Results of experimental and numerical study indicate that, during catalytic oxidation of lean VOCs in reverse flow reactor, the mutual inhibition effect between different kinds of hydrocarbon can be neglected.     

Eld’s Deer Translocated to Human-Inhabited Areas Become Nocturnal

As human populations expand and nonhuman animals decline, understanding the interactions between people and wildlife is essential. For endangered species, appreciating the effect of human disturbance can be important for their conservation. However, a human disturbance angle is often absent from ecological research, despite growing evidence of the negative impact of nonfatal human interference. Here, we monitored Hainan Eld’s deer living within a reserve and translocated animals living amongst villagers. We show that translocated deer deviated from a crepuscular activity pattern and became increasingly nocturnal, and most active when villagers were not. It appears that translocated deer adapted over time to human disturbance and this pattern is similar to that of other species during periods of hunting. People do not pose an actual threat to Eld’s deer, but their presence triggered a response akin to predator avoidance and may be interfering with broader aspects of their biology and conservation.