微絮凝——直接过滤技术的研究与应用进展

对微絮凝—直接过滤技术在城市给水处理和城市废水的深度处理中的研究与应用现状做了概述 ,并对以后的研究工作提出一些建议。     

流动注射分光光度法测定水中的氯离子

本文采用流动注射分析（ＦＩＡ）技术．载流中含有Ｈｇ（ＳＣＨ）２和Ｆｅ２＋，注入试样中的氯离子与Ｈｇ（ＳＣＨ），反应，释放出ＳＣＨ－，后者与Ｆｅ２＋形成红色Ｆｅ（ＳＣＨ）给离子，其强度用分光光度法在４８０ｎｍ处测定．记录的吸收峰高度与试样中氯离子浓度成正比．线性范围６．０—１８μｍ／ｍＬＣｌ，检出限达０．１２μｇ／ｍＬＣｌ－．对６．０μｇ／ｍＬＣｌ－连续测定１１次，其ＲＳＤ为３．９％．出样频率为９０样／小时．方法已用于水样中氯离子的测定．     

Sulfate aerosols forcing: An estimate using a three-dimensional interactive chemistry scheme

The tropospheric sulfate radiative forcing has been calculated using an interactive chemistry scheme in LMD-GCM. To estimate the radiative forcing of sulfate aerosol on climate, a consistent interaction between atmospheric circulation and radiation computation has been allowed in LMD-GCM. The model results indicate that the change in the sulfate aerosols number concentration is negatively correlated to the indirect radiative forcing. The model simulated annual mean direct radiative forcing ranges from −0.1 to −1.2 W m⁻², and indirect forcing ranges from −0.4 to −1.6 W m⁻². The global annual mean direct effect estimated by the model is −0.48 W m⁻², and that of indirect is −0.68 W m⁻².     

Frontier science and challenges on offshore carbon storage

● The main direct seal up carbon options and challenges are reviewed. ● Ocean-based CO₂ replacement for CH₄/oil exploitation is presented. ● Scale-advantage of offshore CCS hub is discussed. Carbon capture and storage (CCS) technology is an imperative, strategic, and constitutive method to considerably reduce anthropogenic CO₂ emissions and alleviate climate change issues. The ocean is the largest active carbon bank and an essential energy source on the Earth’s surface. Compared to oceanic nature-based carbon dioxide removal (CDR), carbon capture from point sources with ocean storage is more appropriate for solving short-term climate change problems. This review focuses on the recent state-of-the-art developments in offshore carbon storage. It first discusses the current status and development prospects of CCS, associated with the challenges and uncertainties of oceanic nature-based CDR. The second section outlines the mechanisms, sites, advantages, and ecologic hazards of direct offshore CO₂ injection. The third section emphasizes the mechanisms, schemes, influencing factors, and recovery efficiency of ocean-based CO₂-CH₄ replacement and CO₂-enhanced oil recovery are reviewed. In addition, this review discusses the economic aspects of offshore CCS and the preponderance of offshore CCS hubs. Finally, the upsides, limitations, and prospects for further investigation of offshore CO₂ storage are presented.     

钢渣对直接大红4BE染料的脱色性能

采用搅拌吸附的方法,在混凝搅拌装置中考察了钢渣对直接大红4BE染料废水脱色率的影响因素及其机理。结果表明,当初始pH值为7.0、染料初始浓度为100 mg/L、钢渣目数为100～120目、用量为10.0 g时,按染料与钢渣的质量比2∶1（mg/g）、转速为200 r/min搅拌吸附,脱色效果较好。当反应时间为100 min时,脱色率为97.14%,可达纺织染整工业水污染物排放标准中色度的Ⅰ类标准。吸附过程的机理主要有快速的物理吸附、OH-与带色素的阴离子之间的配位体交换及絮凝沉淀作用。     

高岭土负载纳米铁镍双金属去除水中偶氮染料直接耐晒黑G

采用液相还原法制备焙烧高岭土负载纳米铁镍双金属（CK-Fe/Ni）。考察了在不同条件下,如pH、投加量、初始浓度、温度等,对负载型纳米铁镍双金属降解水中偶氮染料直接耐晒黑G的影响及动力学研究。结果表明：在pH=9.49、温度为30℃、负载型纳米铁镍双金属的投加量为1.05 g/L、搅拌速度为60 r/min,经过20 min反应后,负载型纳米铁镍双金属降解水中偶氮染料直接耐晒黑G的去除率达到了99.98%。吸附和电镜表征结果表明,作为载体的焙烧高岭土起着吸附直接耐晒黑G和分散纳米铁镍双金属颗粒的作用导致反应活性提高。降解动力学数据表明,负载型纳米铁镍双金属对直接耐晒黑G的降解过程符合伪一级反应动力学规律,速率常数k随负载型纳米铁镍双金属的投加量的增加而提高,表观活化能为19.72 kJ/mol。最后,利用高岭土负载纳米铁镍双金属对废水处理,结果表明,负载型纳米铁镍双金属在实际废水中对直接耐晒黑G的去除率达到了99.98%。     

Evaluation of Poly(lactic acid) and Sugar Beet Pulp Green Composites

Poly(lactic acid) (PLA) and sugar beet pulp (SBP) were compounded by twin-screw extrusion and injection molded into composite forms. Specific mechanical energy decreased with the addition of SBP during processing. PLA–SBP composites retained more tensile strength than expected based on the Nicolais–Narkis model especially at high levels of SBP suggesting adhesion between SBP and PLA. The thermal characteristics of PLA were not affected by thermo-mechanical processing or by the incorporation of SBP up to 30% weight basis. PLA and PLA–SBP composites had similar tensile properties to other thermoplastic resins and may be used as a cost-competitive replacement.

Does female plumage coloration signal parental quality? A male removal experiment with the bluethroat (Luscinia s. svecica)

Females in several sexually dimorphic species with conventional sex roles possess ornamental traits that resemble those found in males. The evolution of such traits, however, is still poorly understood. Bluethroats (Luscinia s. svecica) are socially monogamous, sexually dichromatic passerine birds, in which female throat patch coloration varies from near absence to near full expression of male-like coloration. A recent study, demonstrating that male bluethroats prefer colourful females, suggests that female coloration is subject to sexual selection through male choice. However, the benefits males may gain from mating with colourful females have not yet been identified. In this study we tested the hypothesis that female coloration signals parental quality (the good-parent hypothesis). During the course of the same day, we recorded female care both in the presence and the absence of the male mate. The latter was done to eliminate the confounding effect of variable male care by removing the male temporarily. Female coloration did not correlate with female feeding rates either in the presence or in the absence of the male. Female feeding rates in the absence and the presence of the male were positively, although weakly, correlated. Female coloration did not correlate with female ability to compensate for the loss of male care, or with the change in brood mass during male removal. Therefore, there is no evidence for the good-parent hypothesis to explain female plumage coloration in bluethroats. Received: 4 March 1999 / Received in revised form: 14 October 1999 / Accepted: 23 October 1999     

Thermodynamics,economics and systems thinking: What role for air capture of CO2?

Air capture has recently been advanced by several parties as a solution to the problem of constraining – and ultimately reducing – atmospheric CO₂ in response to climate change. However, there are significant barriers pertaining to scale, energy needs and cost, which will hugely challenge the effectiveness and practicality of air capture. This paper examines the thermodynamics, energetics and economics and politics of air capture. These compare unfavourably with alternative approaches to atmospheric greenhouse gas reduction. An analysis is made of the energy cost of the one favoured DAC technology for which experimental results are available in the open literature – temperature/vacuum swing adsorption, and of one point source capture technology – oxyfiring of refinery FCCUs. We also examine the engineering effort required to implement atmospheric capture on a scale at which it could significantly reduce atmospheric levels of CO₂; and questions are addressed regarding its practicability and appropriateness. The analysis demonstrates that air capture remains at best a peripheral activity, at worst a distraction, until point sources of greenhouse gas emissions such as power stations, industrial flue gases, shale gas wellheads, anaerobic digestion plants and landfill sites have been completely decarbonised. When these and so many other unaddressed factors are affecting our global climate, the pursuit air capture, the ultimate “end-of-pipe” solution, is inappropriate.