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11.
Mikael Karlsson 《Journal of Agricultural and Environmental Ethics》2003,16(1):51-62
In spite of stricter provisions inthe new EU directive on deliberate release ofgenetically modified organisms (GMOs), criticsstill advocate a moratorium on permits forcultivation of GMOs. However, in an attempt tomeet concerns raised by the public, thedirective explicitly gives Member States thepossibility to take into consideration ethicalaspects of GMOs in the decision-making. Thisarticle investigates the potential effects ofsuch formulation by means of an empiricalanalysis of experiences gained the last yearsfrom similar Swedish regulations for GMOs,aiming at promoting sustainable development.The faulty implementation shown in the Swedishcase indicates that legal stipulations forethics as such have limited importance. It issuggested that public participation is animportant factor for successful implementationof the ethics of sustainable development. 相似文献
12.
Anne Ingeborg Myhr Terje Traavik 《Journal of Agricultural and Environmental Ethics》2003,16(3):227-247
Risk governance of GM plants and GMfood products is presently subject to heatedscientific and public controversies. Scientistsand representatives of the biotechnologyindustry have dominated debates concerningsafety issues. The public is suspicious withregard to the motives of scientists, companies,and political institutions involved. Thedilemmas posed are nested, embracing valuequestions, scientific uncertainty, andcontextual issues. The obvious lack of data andinsufficient information concerning ecologicaleffects call for application of thePrecautionary Principle (PP). There are,however, divergent opinions among scientistsabout the relevance of putative hazards,definition of potential ``adverse effects,' andwhether actions should be taken to preventharm. The reliance on the concept ofsubstantial equivalence in safety evaluation ofGM food is equally controversial. Consequently,value assumptions embedded in a scientificframework may be a barrier for employment ofthe PP. One of our major conclusions is thatprecautionary GMP usage requires riskassessment criteria yet undeveloped, as well asbroader and more long-term conceptions of risk,uncertainty, and ignorance. Conflicts ofinterest and public participation are otherissues that need to be taken intoconsideration. GMP governance regimes that arejustifiable from a precautionary and ethicalpoint of view must transcend traditionalscientific boundaries to include alternativescientific perspectives as well as publicinvolvement. 相似文献
13.
Assya Pascalev 《Journal of Agricultural and Environmental Ethics》2003,16(6):583-594
Thus far, the moral debateconcerning genetically modified foods (GMF) hasfocused on extrinsic consequentialist questionsabout the health effects, environmental impacts,and economic benefits of such foods. Thisextrinsic approach to the morality of GMF isdependent on unsubstantiated empirical claimsand fails to account for the intrinsic moralvalue of food and food choice and theirconnection to the agent's concept of the goodlife. I develop a set of objections to GMFgrounded in the concept of integrity andmaintain that food and food choice can beintimately connected to the agent's personalintegrity. I argue that due to the constitutionof GMF and the manner in which they areproduced, such foods are incompatible with thefundamental values and integrity of certainindividual moral agents or groups. I identifythree types of integrity that are threatened byGMF: religious, consumer, and integrity basedon certain other moral or metaphysical grounds.I maintain that these types of integrity aresufficiently important to provide justificationfor political and societal actions to protectthe interests of those affected. I conclude byproposing specific steps for handling GMFconsistent with the moral principles ofinformed consent, non-maleficence, and respectfor the integrity of all members of society.They include mandatory labeling of GMF, theimplementation of a system for control andregulations concerning such foods, andguaranteed provision of conventional foods. 相似文献
14.
试验针对存在的氟污染饮用水问题,将天然沸石用NaOH和Al2(SO4)3溶液改性制成除氟材料.静态试验研究表明:改性沸石除氟吸附反应快,其最佳pH值范围为5~9,而且对氟离子具有较好的离子选择性能.通过动态试验研究发现,降低进水流量和原水浓度可以增大滤层的吸附容量.两种再生方式对比试验表明:用Al2(SO4)3溶液再生效果优于用NaOH和Al2(SO4)3溶液联合再生. 相似文献
15.
Alan?Rubelrstreiffer@wisc.edu" title="arubel@wisc.edu rstreiffer@wisc.edu" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Robert?Streiffer 《Journal of Agricultural and Environmental Ethics》2005,18(1):75-84
In her recent article, “Does autonomy count in favor of labeling genetically modified food?,” Kirsten Hansen argues that in Europe, voluntary negative labeling of non-GM foods respects consumer autonomy just as well as mandatory positive labeling of foods with GM content. She also argues that because negative labeling places labeling costs upon those consumers that want to know whether food is GM, negative labeling is better policy than positive labeling. In this paper, we argue that Hansen’s arguments are mistaken in several respects. Most importantly, she underestimates the demands of respecting autonomy and overestimates the cost of positive labeling. Moreover, she mistakenly implies that only a small minority of people desire information about GM content. We also explore the extent to which her arguments would apply to the US context, and argue that any discussion of the relationship between autonomy and labeling should include not just considerations of consumer autonomy but also considerations of what we call citizen autonomy. 相似文献
16.
以城市污水处理厂剩余污泥为原料,利用磷酸活化-微波热解制取改性污泥。以此污泥作为吸附剂,对含Cd2+废水进行了吸附实验研究。考察了溶液反应时间、Cd2+浓度、pH值和吸附剂用量对镉吸附去除效果的影响;利用等温吸附实验作出吸附等温线,并考察了改性污泥吸附剂吸附Cd2+的动力学方程。实验结果表明,改性污泥对Cd2+有良好的吸附性能,吸附最佳pH值为6.0,吸附较好地符合一级动力学吸附模型和Langmuir-Freundlich等温吸附方程,吸附为物理吸附,吸附反应发生12 h后达到吸附平衡。 相似文献
17.
针对水厂低浊高藻水的处理难题,研究了改性凹凸棒土(改性凹土)联合聚合氯化铝(PAC)强化混凝的除藻除浊效果。设计实验原水条件为叶绿素a(chl-a)浓度为98.58~110.35μg/L,浊度(5.6±0.5)NTU。考察了PAC和改性凹土的复配投加量、混凝沉淀时间、pH、投加顺序、搅拌速率等工艺参数对Chl-a和浊度耦合去除效果的影响。结果表明,"PAC+改性凹土"对Chl-a和浊度的去除效果明显优于单投PAC的效果。当PAC投药量12 mg/L,改性凹土投药量10 mg/L,沉淀时间20 min时,对Chl-a和浊度的去除率可分别达到92.5%和89.2%,可至少减少40%的PAC投量,且形成的矾花密实,沉降速度快,去除效率高。最适pH范围为7~8。投加顺序应为先投加改性凹土,混合搅拌转数宜慢速,可控制为50 r/min。 相似文献
18.
19.
锆-十六烷基三甲基氯化铵改性活性炭对水中硝酸盐和磷酸盐的吸附特性 总被引:3,自引:3,他引:0
采用锆(Zr)和阳离子表面活性剂十六烷基三甲基氯化铵(CTAC)对活性炭进行联合改性,考察了所制备的Zr-CTAC改性活性炭对水中硝酸盐和磷酸盐的吸附去除作用,并探讨了相关的吸附去除机制.结果表明,Zr-CTAC改性活性炭对水中硝酸盐和磷酸盐均具备较好的吸附去除能力.Zr-CTAC改性活性炭对硝酸盐和磷酸盐吸附动力学过程满足准二级动力学模型.Langmuir、Freundlich和Dubinin-Radushkevich(D-R)等温吸附模型可以较好地描述Zr-CTAC改性活性炭对水中硝酸盐的等温吸附过程,Langmuir和D-R等温吸附模型可以较好地描述Zr-CTAC改性活性炭对水中磷酸盐等温吸附过程,通过Langmuir模型计算得到吸附剂对硝酸盐和磷酸盐的最大单位吸附量分别为7.58 mg·g-1和10.9 mg·g-1.高的p H会抑制Zr-CTAC改性活性炭对水中硝酸盐和磷酸盐的吸附.水中共存的Cl-、HCO-3和SO2-4等阴离子均会抑制Zr-CTAC改性活性炭对硝酸盐和磷酸盐的吸附,且对吸附硝酸盐的抑制作用较强而对吸附磷酸盐的抑制作用较弱.水中共存的磷酸盐对Zr-CTAC改性活性炭吸附硝酸盐的抑制作用较强,而水中共存的硝酸盐对Zr-CTAC改性活性炭吸附磷酸盐的抑制作用较弱.1 mol·L-1Na Cl溶液可以使90%左右被吸附到Zr-CTAC改性活性炭表面上的硝酸盐解吸下来.1 mol·L-1的Na OH溶液可以使78%左右被吸附到Zr-CTAC改性活性炭表面上的磷酸盐解吸下来.Zr-CTAC改性活性炭对硝酸盐的吸附机制主要包括阴离子交换作用和静电吸引作用,对磷酸盐的吸附机制主要包括配位体交换作用、阴离子交换作用和静电吸引作用.上述结果说明Zr-CTAC改性活性炭适合作为一种吸附剂去除废水中的硝酸盐和磷酸盐. 相似文献
20.
实验采用改良型CAST工艺,以生活污水为研究对象,考察了C/P、回流比及温度等不同运行模式对系统除磷性能的影响.结果表明,常温条件下进水C/P由50升至100,系统除磷率均值从15%迅速升至95.6%,除磷性能显著提高;继而降低C/P至75,除磷性能因进水碳源不足再度下降,除磷率均值为51.4%,且长期投加易降解碳源引发系统污泥膨胀并导致污泥大量流失.C/P较低情况下,回流比由25%降低至12.5%,除磷性能提高2.3倍,继续降低回流比至0,除磷性能反而下降;温度实验研究则表明,低温系统(14℃±1℃),除磷率稳定维持在90%以上,而高温短程硝化系统(27℃±1℃)除磷率仅为14.1%,可见低温更有利于系统磷的去除.吸磷小试发现,常温系统污泥以O_2、NO_3~-和NO_2~-为电子受体均能进行吸磷,而低温系统污泥能以O_2、NO_3~-为电子受体进行吸磷,高温系统污泥则仅能以O_2为电子受体进行少量吸磷.此外,实验还发现,系统短期闲置导致的污泥"饥饿"有利于系统除磷率的提高. 相似文献