The effect of freezing on the composition of supercooled droplets—II. Retention of S(IV)

S(IV) dissolved in droplets is partially evolved as SO₂ during freezing. A spray of droplets with average diameter 39μm, produced by an ultrasonic transducer, was let to fall through a controlled atmosphere with known SO₂ concentration, at varying temperatures between −8 and −23°C, attaining thermal and chemical equilibrium. In a first arrangement, the droplets fell by gravitation on an ice surface. Two other arrangements simulated the riming ventilation conditions: in one series of experiments, the droplets were projected by a gas jet at several m s⁻¹ against a target; in another, the droplets were caught by rotating rods. The fraction of S(IV) retained in the ice Γ was determined by analysis of the samples and comparison with the equilibrium concentration in the liquid droplets. Samples collected by gravitation showed a retention coefficient Γ = 0.25 + 0.012 T_s (T_s = supercooling); rime samples showed large dispersion in the results, the retention coefficient being best represented by an average value Γ = 0.62, independent of temperature.     

Scaling down the “Netherlands Fallacy”: a local-level quantitative study of the effect of affluence on the carbon footprint across the United States

Much quantitative research examining the determinants of the ecological footprint has been conducted cross-nationally, where data on cross-boundary flows have been readily available. While local-level studies of the footprint do exist for specific localities, most quantitative research at this scale has examined direct environmental impacts attributed to the internal activities of the locality, for instance, carbon emissions. Our analysis builds on this previous work by exploiting a local-level carbon footprint dataset with coverage for 28,321 zip codes across the United States. Following prior research, we focus on the effect of local affluence, measured in terms of median household income. In spatial regression models, we regress the per capita carbon footprint on local affluence, controlling for a variety of other factors. Consistent with previous work, we find that affluence is positively correlated the carbon footprint and there is no evidence of an environmental Kuznets curve. In the conclusion, we review the results of the study and discuss their implications for policy, specifically in terms of cross-boundary environmental problems.     

Sensitized effect of β-cyclodextrin on the fluorescence in the determination of carbaryl

Based on the significant enhancement of fluorescence intensity of carbaryl in inclusion complex, a spetrofluorimetdc method with high sensitivity was developed for the determination of carbaryl in aqueous solution. Under the optimum conditions, the complex had excitation and emission maxima at 278 nm and 332 nm, respectively. The linear range of the method was 7.0 ng/ml-1500 ng/ml with a detection limit of 1.2 ng/ml. The proposed method was successfully used to determine quantitativelv of carbarvl in cottonseeds.     

Sensitized effect of β-cyclodextrin on the fluorescence in the determination of carbaryl

Based on the significant enhancement of fluorescence intensity of carbaryl in inclusion complex, a spetrofluorimetric method with high sensitivity was developed for the determination of carbaryl in aqueous solution. Under the optimum conditions, the complex had excitation and emission maxima at 278 nm and 332 nm, respectively. The linear range of the method was 7.0 ng/ml-1500 ng/ml with a detection limit of 1.2 ng/ml. The proposed method was successfully used to determine quantitatively of carbaryl in cottonseeds.     

On the effect of Fe(Ⅲ) on proliferation of Microcystis aeruginosa at high nitrate and low chlorophyll condition

The impact of Fe concentrations on the growth of Microcystis aeruginosa in aquatic systems under high nitrate and low chlorophyll conditions was studied. The responses of cell density,total and cell chlorophyll-a intracellular Fe content and organic elemental composition of M.aeruginosa to different concentration gradients of Fe(Ⅲ) in the solutions were analysed. The results showed that the proliferation speeds of M. aeruginosa were:(1) decelerated when the Fe(Ⅲ) concentration was lower than 50 μg/L in the solutions,(2) promoted and positively related to the increase of Fe(Ⅲ) concentration from 100 to 500 μg/L in the solutions over the experimental period, and(3) promoted in the early stage but decelerated in later stages by excess adsorption of Fe by cells when the Fe(Ⅲ) concentration was higher than 500 μg/L in the solutions. The maximum cell density, total and cell chlorophyll-a were all observed at 500 μg Fe(Ⅲ)/L concentration. The organic elemental composition of M. aeruginosa was also affected by the concentration of Fe(Ⅲ) in the solutions, and the molecular formula of M. aeruginosa should be expressed as C_(7–7.5)H_(14)O_(0.8–1.3)N_(3.5–5)according to the functions for different Fe(Ⅲ)concentrations. Cell carbon and oxygen content appeared to increase slightly, while cell nitrogen content appeared to decrease as Fe(Ⅲ) concentrations increased from 100 to 500 μg/L in the solutions. This was attributed to the competition of photosynthesis and nitrogen adsorption under varying cell Fe content.     

Oxidation of Cr(Ⅲ) on birnessite surfaces: The effect of goethite and kaolinite

Oxidation of Cr(Ⅲ) by manganese oxides may pose a potential threat to environments due to the formation of toxic Cr(Ⅵ) species. At present, it was still unclear whether the extent of Cr(Ⅲ) oxidation and fate of Cr(Ⅵ) would be changed when manganese oxides co-exist with other minerals, the case commonly occurring in soils. This study investigated the influence of goethite and kaolinite on Cr(Ⅲ) oxidation by birnessite under acidic p H condition(p H 3.5)and background electrolyte of 0.01 mol/L Na Cl. Goethite was found not to affect Cr(Ⅲ)oxidation, which was interpreted as the result of overwhelming adsorption of cationic Cr(Ⅲ) onto the negatively-charged birnessite(point of zero charge(PZC) 3.0) rather than the positively-charged goethite(PZC = 8.8). However, more Cr(Ⅵ) would be retained by the surface with the increase in addition of goethite because of its strong ability on adsorption of Cr(Ⅵ) at low p H. Moreover, either Cr(Ⅲ) oxidation or distribution of the generated Cr(Ⅵ)between the solid and solution phases was not affected by kaolinite(PZC 3.0), indicating its low affinity for Cr species. Reactions occurring in the present mixed systems were suggested, which could be partly representative of those in the soils and further indicates that the mobility and risk of Cr(Ⅵ) would be decreased if goethite was present.     

A prehistoric tsunami induced long-lasting ecosystem changes on a semi-arid tropical island—the case of Boka Bartol (Bonaire, Leeward Antilles)

The Caribbean is highly vulnerable to coastal hazards. Based on their short recurrence intervals over the intra-American seas, high-category tropical cyclones and their associated effects of elevated storm surge, heavy wave impacts, mudslides and floods represent the most serious threat. Given the abundance of historical accounts and trigger mechanisms (strike-slip motion and oblique collision at the northern and southern Caribbean plate boundaries, submarine and coastal landslides, volcanism), tsunamis must be considered as well. This paper presents interdisciplinary multi-proxy investigations of sediment cores (grain size distribution, carbonate content, loss-on-ignition, magnetic susceptibility, microfauna, macrofauna) from Washington-Slagbaai National Park, NW Bonaire (Leeward Antilles). No historical tsunami is recorded for this island. However, an allochthonous marine layer found in all cores at Boka Bartol reveals several sedimentary criteria typically linked with tsunami deposits. Calibrated ¹⁴C data from these cores point to a palaeotsunami with a maximum age of 3,300 years. Alternative explanations for the creation of this layer, such as inland flooding during tropical cyclones, cannot entirely be ruled out, though in recent times even the strongest of these events on Bonaire did not deposit significant amounts of sediment onshore. The setting of Boka Bartol changed from an open mangrove-fringed embayment into a poly- to hyperhaline lagoon due to the establishment or closure of a barrier of coral rubble during or subsequent to the inferred event. The timing of the event is supported by further sedimentary evidence from other lagoonal and alluvial archives on Bonaire.     

The effect of continuous Ni(Ⅱ) exposure on the organic degradation and soluble microbial product(SMP) formation in two-phase anaerobic reactor

A two-phase anaerobic reactor fed with glucose substrate (3 g chemical oxygen demand (COD)/L) was used to investigate the effects of toxic metals on the degradation of organics and the soluble microbial product (SMP) formation. Low concentrations of Ni(II) (5 and 10 mg/L) promoted the acid phase, whereas high concentrations (15, 20, and 25 mg/L) exhibited an inhibitory effect on, but did not alter the fermentative method, which mainly involved the fermentation of propionic acid. The methanogenic microorganism exhibited a strong capability adapting constantly increased Ni(II) levels. The acid phase was an accumulation stage of SMP. In the absence of Ni(II), the high-molecular-weight material in the effluent SMP mainly contained polysaccharide, tryptophan, and casein. Methanogens metabolized most of the polysaccharide, the whole tryptophan content, and part of the casein, leading to the presence of humic acid and protein in effluent. After Ni(II) dosage, the protein and polysaccharide of the acid phase increased, and tryptophan changed, while casein remained stable. More protein than polysaccharide was produced, suggesting the prominent function of protein when addressing the negative effect of toxic metals. The analysis of DNA confirmed the change of bacterial activity.     

Aqueous S(IV) oxidation—III. Catalytic effect of soot particles

The paper reports on studies of S(IV) oxidation in aqueous media containing suspensions of soot particles from domestic coal burning and activated carbon RB-1. The results show that the reaction rate depends upon dissolved iron leached from soot particles. At a low initial pH (⩽4), Fe(III) species are responsible for the high oxidation rate, whereas at a higher initial pH (5.2 – 5.5), Fe(II), which is primarily present in soot suspensions, acts as a catalyst. These homogeneous reactions dominate the catalytic effect of the coal soot surface. It is shown that the mechanism oof S(IV) oxidation catalysed by activated carbon is quite different.     

Adsorption of zinc on manganite (γ-MnOOH):particle concentration effect and adsorption reversibility

The adsorption and desorption processes of Zn(Ⅱ) on γ-MnOOH as a function of particle concentrations (Cp) were studied. An obvious Cp effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of Cp, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of Cp. The Cp-reversibility relationship confirmed the metastable-equilibrium adsorption (MEA) inequality (Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption density Г is not a state variable, the Cp-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory.     

Adsorption of zinc on manganite(γ-MnOOH): particle concentration effect and adsorption reversibility

The adsorption and desorption processes of Zn(Ⅱ) on τ-MnOOH as a function of particle concentrations (Cp) were studied. An obvious Cp effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of Cp, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of Cp. The Cp-reversibility relationship confirmed the metastable-equilibrium adsorption (MEA) inequality (Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption densitιy ι is not a state variable, the Cp-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory.     

Effect of sorbed and desorbed Zn(Ⅱ) on the growth of a green alga (Chlorella pyrenoidosa)

Toxic effect of Zn(Ⅱ)on a green alga(ChloreUa pyrenoidosa)in the presence of sepiolite and kaolinite was investigated.The Zn-free clays were found to have a negative impact on the growth of C.pyrenoidosa in comparison with control samples(without adding any clay or Zn(Ⅱ)).When Zn(Ⅱ)was added,the algae in the presence of clays could be better survived than the control samples,which was actually caused by a decrease in Zn(Ⅱ)concentration in the solution owing to the adsorption of Zn(Ⅱ)on the clays.When the solution system was diluted,the growth of algae could be further inhibited as compared to that in a system which had the same initial Zn(Ⅱ)concentration as in the diluted system.This in fact resulted from desorption of Zn(Ⅱ)from the zinc-contaminated clays,although the effect varied according to the different desorption capabilities of sepiolite and kaolinite.Therefore the adsorption and desorption processes of Zn(Ⅱ)played an important part in its toxicity,and adsorption and desorption of pollutants on soils/sediments should be well considered in natural eco-environmental systems before their risk of toxicity to aquatic organisms was assessed objectively.     

Commercial development of energy—environmentally sound technologies for the auto-industry: the case of fuel cells

The economic importance of energy and environmental issues is continuously increasing, affecting both process and product design in business. The energy crisis in California in 2001 made this basic issue universal. New technologies are expected to reduce pollution derived both from production processes and products, with costs that are still unknown and in competition with more mature technologies high. Nevertheless, until now there is still little, but growing knowledge concerning the process of technological innovation in the fields of energy and environment.In this paper we analyze the development of zinc air fuel cell (ZAFC) and its transfer from a research laboratory to potential mass production. ZAFC are a new ‘environmentally sound technology’, proven to have commercial value, that can be used for substituting internal combustion engines (ICEs) and meeting zero emission vehicles (ZEV) regulations. Although ZAFC performances are higher than traditional electric batteries ones, commercial costs are still high. Hence the pathway to mass production may come from stationary application of fuel cells for power.In contrast to the conventional ‘paradigmatic’ approach, we argue that the existing economic and organizational literature concerning technological innovation is not able to fully explain steps followed in commercializing energy—environmentally sound technologies. Existing models mainly consider adopting problems, which are due to market uncertainty, weak application, lack of a dominant design, and problems in reconfiguring existing organizational routines. Above all ‘market power’ exists in terms of control over technological innovation and its commercial application. Barriers are erected that prevent new technologies such as fuel cells from becoming adapted. Through pro-active government intervention, such as the case in California, new advanced technologies can move rapidly into the marketplace.From this discussion we draw some conclusions and issues for further research concerning policy making for sustaining the process of technological transfer and firms’ strategies in technological innovation.     

Effect of sorbed and desorbed Zn(Ⅱ) on the growth of a green alga (Chlorella pyrenoidosa)

Toxic effect of Zn(Ⅱ) on a green alga (Chlorella pyrenoidasa) in the presence of sepiolite and kaolinite was investigated.The Zn-free clays were found to have a negative impact on the growth of C.pyrenoidosa in comparison with control samples (without adding any clay or Zn(Ⅱ)).When Zn(Ⅱ) was added,the algae in the presence of clays could be better survived than the control samples,which was actually caused by a decrease in Zn(Ⅱ) concentration in the solution owing to the adsorption of Zn(Ⅱ) on the clays.When the solution system was diluted,the growth of algae could be further inhibited as compared to that in a system which had the same initial Zn(Ⅱ) concentration as in the diluted system.This in fact resulted from desorption of Zn(Ⅱ) from the zinc-contaminated clays,although the effect varied according to the different desorption capabilities of sepiolite and kaolinite.Therefore the adsorption and desorption processes of Zn(Ⅱ) played an important part in its toxicity,and adsorption and desorption of pollutants on soils/sediments should be well considered in natural eco-environmental systems before their risk of toxicity to aquatic organisms was assessed objectively.     

Meeting emission targets under uncertainty—the case of Finnish non-emission-trading sector

The European Union (EU) has set a target to reduce its greenhouse gas (GHG) emissions at least 10 % below the 2005 levels by 2020 in the non-Emission Trading Sector (non-ETS). As part of this, each Member State has a binding national emission limitation target for the non-ETS sector. Finland’s target, examined as a case study in this paper, is to reduce emissions at least 16 % below 2005 levels by 2020. The objective of this study is to find cost optimal mitigation portfolios that meet Finland’s reduction target and to analyze the risks of not attaining the emission target or exceeding the assumed costs. The question was addressed with a stochastic optimization model, Stochastic Optimization of non-ETS Emissions (SONETS) selecting separate mitigation measures that meet the target on expectation. The results show that optimal portfolios include relatively high uncertainty both in costs and achieved reductions. The prices of crude oil and diesel, and the abatement cost of reducing hydrofluorocarbon (HFC) emissions seem to account for the majority of uncertainty regarding total costs. The baseline predictions for various non-ETS subsectors (such as transport and agriculture) were found to have the greatest contribution to the uncertainty of attaining emission target. The results also show that some abatement actions are chosen in nearly all efficient portfolios, while other actions are seldom chosen. For example replacing oil burners in the end of technical life time or recovery of methane (CH₄) from waste are often chosen whereas ban of landfilling of organic waste is chosen extremely seldom. It also seems that the results are somewhat sensitive to the inclusion or exclusion of the interdependencies of mitigation measures.     

The effect of interaction between Bacillus subtilis DBM and soil minerals on Cu(Ⅱ) and Pb(Ⅱ) adsorption

The effects of interaction between Bacillus subtilis DBM and soil minerals on Cu(Ⅱ)and Pb(Ⅱ)adsorption were investigated.After combination with DBM,the Cu(Ⅱ)and Pb(Ⅱ)adsorption capacities of kaolinite and goethite improved compared with the application of the minerals independently.The modeling results of potentiometric titration data proved that the site concentrations of kaolinite and goethite increased by 80%and 30%,respectively after combination with DBM.However,the involvement of functional groups in the DBM/mineral combinations resulted in lower concentrations of observed sites than the theoretical values and led to the enhancement of desorption rates by NH_4NO_3 and EDTA-Na_2.The DBM-mineral complexes might also help to prevent heavy metals from entering DBM cells to improve the survivability of DBM in heavy metal-contaminated environments.During the combination process,the extracellular proteins of DBM provided more binding sites for the minerals to absorb Cu(Ⅱ)and Pb(Ⅱ).In particular,an especially stable complexation site was formed between goethite and phosphodiester bonds from EPS to enhance the Pb(Ⅱ)adsorption capacity.So,we can conclude that the DBM–mineral complexes could improve the Cu(Ⅱ)and Pb(Ⅱ)adsorption capacities of minerals and protect DBM in heavy metal-contaminated environments.     

Summary report on the activities of the first session of SCOPE China/CAST (1988.7-1992.6)

1 Founding of SCOPE China CAST supported the setting up of SCOPE China in early 1988. Mr. Lu Jingting, Professors Ma Shijun and Zhuang Yahui participated in the 7th SCOPE General As- sembly in June, 1988, at which SCOPE China/CAST was admitted as a SCOPE mem-ber. Then the first plenary meeting of SCOPE China was held in Beijing in July, 1988 and the Constitution of SCOPE China was adopted and the committee of