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121.
为了在酸性条件下实现剩余污泥中磷的高效回收,对pH=3时剩余污泥水解酸化过程中氨氮、正磷酸盐和钙镁离子的溶出现象以及磷回收进行了研究分析。结果表明:当pH=3时,所溶出的氨氮、镁离子和钙离子与磷酸盐的摩尔比均大于1,能满足采用鸟粪石沉淀法或者羟磷灰石沉淀法回收磷的要求;但所溶出的钙镁离子的摩尔比大于1,会对鸟粪石沉淀法回收磷的顺利进行有较大影响;有无外加镁剂对磷回收率影响不大。采用改型后的镁型强酸性阳离子交换树脂进行离子交换可以得到较高纯度的鸟粪石沉淀产品,通过XRD检测其纯度为95%以上。 相似文献
122.
123.
The management of endangered species under climate change is a challenging and often controversial task that incorporates input from a variety of different environmental, economic, social, and political interests. Yet many listing and recovery decisions for endangered species unfold on an ad hoc basis without reference to decision‐aiding approaches that can improve the quality of management choices. Unlike many treatments of this issue, which consider endangered species management a science‐based problem, we suggest that a clear decision‐making process is equally necessary. In the face of new threats due to climate change, managers’ choices about endangered species require closely linked analyses and deliberations that identify key objectives and develop measurable attributes, generate and compare management alternatives, estimate expected consequences and key sources of uncertainty, and clarify trade‐offs across different dimensions of value. Several recent cases of endangered species conservation decisions illustrate our proposed decision‐focused approach, including Gulf of Maine Atlantic salmon (Salmo salar) recovery framework development, Cultus Lake sockeye salmon (Oncorhynchus nerka) management, and Upper Columbia River white sturgeon (Acipenser transmontanus) recovery planning. Estructuración de Decisiones para Manejar Especies Amenazadas y en Peligro en un Clima Cambiante 相似文献
124.
NICHOLAS J. DECESARE JESSE WHITTINGTON MARK HEBBLEWHITE HUGH ROBINSON MARK BRADLEY LALENIA NEUFELD MARCO MUSIANI 《Conservation biology》2011,25(2):365-373
Abstract: Maintenance of viable populations of many endangered species will require conservation action in perpetuity. Efforts to conserve these species are more likely to be successful if their reliance on conservation actions is assessed at the population level. Woodland caribou (Rangifer tarandus caribou) were extirpated recently from Banff National Park, Canada, and translocations of caribou to Banff and neighboring Jasper National Park are being considered. We used population viability analysis to assess the relative need for and benefits from translocation of individuals among caribou populations. We measured stochastic growth rates and the probability of quasi extinction of four populations of woodland caribou with and without translocation. We used two vital rates in our analysis: mean adult female survival and mean number of calves per breeding‐age female as estimates of mean fecundity. We isolated process variance for each vital rate. Our results suggested the Tonquin caribou population in Jasper is likely to remain viable without translocation, but that translocation is probably insufficient to prevent eventual extirpation of the two other populations in Jasper. Simulated reintroductions of caribou into Banff resulted in a 53–98% probability of >8 females remaining after 20 years, which suggests translocation may be an effective recovery tool for some caribou populations. 相似文献
125.
《International Journal of Sustainable Engineering》2013,6(2):106-120
There is a widespread recognition of the need for better information sharing and provision to improve the viability of end-of-life (EOL) product recovery operations. The emergence of automated data capture and sharing technologies such as RFID, sensors and networked databases has enhanced the ability to make product information; available to recoverers, which will help them make better decisions regarding the choice of recovery option for EOL products. However, these technologies come with a cost attached to it, and hence the question ‘what is its value?’ is critical. This paper presents a probabilistic approach to model product recovery decisions and extends the concept of Bayes' factor for quantifying the impact of product information on the effectiveness of these decisions. Further, we provide a quantitative examination of the factors that influence the value of product information, this value depends on three factors: (i) penalties for Type I and Type II errors of judgement regarding product quality; (ii) prevalent uncertainty regarding product quality and (iii) the strength of the information to support/contradict the belief. Furthermore, we show that information is not valuable under all circumstances and derive conditions for achieving a positive value of information. 相似文献
126.
电解法处理含镍废水及纯镍的回收 总被引:1,自引:0,他引:1
雷英春 《城市环境与城市生态》2009,(3)
采用电解回收法处理Ni2+含量为2g/L的废水,在阴极回收纯镍。研究了电解电流、极距、NH4Cl浓度、pH值等因素对Ni2+去除率、槽压、阴极能耗的影响,得出最优工艺参数为:温度20℃,电解时间20min时、电解电流300mA,极距15mm,NH4Cl浓度5g/L,pH值8.0,该条件下Ni2+去除率为96.926%,槽压16.21V,阴极能耗22.418kW.h/kg,在阴极可得到沉积6.45μm厚的镍板。 相似文献
127.
本文对小型造纸厂的碱回收在技术上和经济上的可行性进行了分析,作出了当前是中、小型造纸厂搞碱回收的有利时机的初步评价。 相似文献
128.
Paul H. Selman 《Journal of Environmental Planning and Management》1987,30(2):78-83
It is noted that nature conservation has gained progressively in importance as a planning issue. The paper reports on the role of the Nature Conservancy Council, and in particular their Assistant Regional Officers, in consulting over the production of local plans. Local plan policies may assist valuably in the protection of important sites, although sympathetic planning authorities can also assist nature conservation in a variety of other ways. Sustained and systematic liaison with planning authorities is necessary for nature conservation to become a substantive local plan issue. 相似文献
129.
回收PTA废料生产增塑剂 总被引:3,自引:0,他引:3
介绍了扬子石化公司PTA生产过程中所排各种废料的分离提纯及回收利用,对难以回收的氧化残渣的分离回收和利用作了重点论述。提供了用所回收的TA和混合苯二甲本乡生产剂的工艺流程和工艺参数。 相似文献
130.