硅藻土及改性硅藻土在污水处理中的研究

随着城市污水水量增加,水质成分日益复杂,硅藻土作为一种新型的污水处理材料,具有较好的吸附效果。本文描述了硅藻土和改性硅藻土在污水处理中的研究进展,及其改性前后对污染物的去除效果比较,并通过此对比总结了硅藻土及改性硅藻土在水处理中的优缺点,以及其作为一种新型吸附材料为污水处理的研究提供了理论基础。     

铁锰磁性海泡石吸附剂的吸附性实验室研究

本文通过对铁锰磁性海泡石的吸附性试验研究,确定其最佳吸附时间、温度和回收率,得知海泡石磁性吸附剂是一种对活性艳兰吸附效率高,回收方便经济的新型吸附剂,适合工业上面的大规模应用。     

无纺布应用于污水处理的研究现状

无纺布作为一种新型的过滤材料,具有独特的结构,体现出了良好的过滤能力,因此在污水处理领域得到越来越广泛的关注和应用。同时无纺布可以与很多污水处理工艺联用,不仅提高了出水水质,还克服了膜生物反应器造价高、能耗大等缺点。总结了国内外一些针对无纺布以及无纺布与其他工艺联用的研究,并获得了实际的运行参数。     

臭氧/复合滤料生物滤池深度处理饮用水试验研究

根据水污染的特点以及深度处理引用水的规定，以污染物极性视角出发，将活性炭与多孔性软陶粒为新型复合滤料。活性炭可对非极性分子进行吸附，因比陶粒空隙大，对分子直径无特别要求；陶粒具有很强的极性吸附，对不饱和与极性分子的亲和力较强，可选择吸附极化率大的非极性分子。对于CHCl3与氨氮等有机物，陶粒吸附力大于活性炭。本文将生物降解技术、滤料化学与物理吸附、臭氧吸附相结合，分析符合滤料生物滤池深度处理饮用水的能力。     

改性累托石对水环境中氟离子的吸附行为研究

本文对改性累托石去除水溶液中的氟离子性能进行了研究.系统地研究了反应时间、吸附剂投加量、pH、温度等因素对吸附剂除氟性能的影响情况.反应系统达到吸附平衡的时间为100 min.吸附剂最佳投加量为3 g/L.pH值是影响吸附过程的重要因素之一,本研究最佳反应pH范围为5.0～7.0.吸附等温线研究发现改性累托石除氟剂吸附等温线方程均符合Langmuir吸附等温线模型.吸附动力学研究发现动力学数据较好的的符合拟二级动力学模型.本研究对改性累托石除氟的机理进行了探讨.     

生物吸附法处理重金属废水的研究

现代工业排放的重金属废水对环境有严重的负面影响。生物吸附法作为新兴的重金属去除技术,有着广阔的应用前景。本文阐述了生物吸附的机理,介绍了现今国内外对重金属污染处理的新技术方法,并评述了生物吸附法处理重金属废水存在的问题以及发展方向。     

固定化生物反应器在微污染水源水处理中的研究

固定化生物陶粒工艺是一种有效去除水源水中污染物的方法,本文采用固定化生物陶粒反应器对龙虎泡原水进行处理,实验表明,固定化生物工艺对OC的去除率为25.6%,氨氮去除率为64.1%,浊度去除率为83.8%,对UV254的去除率为13.3%,其效果比单纯生物滤池及工程菌液对污染物的去除效果好,OC和氨氮的去除率是为其他两种工艺的两倍.固定化生物反应器对有机物的去除始终保持在很高的水平:对各层微生物的变化情况进行观测分析,指明微生物的衍替规律.最后对成熟滤料进行电镜扫描分析,指出微生物在载体上的生长状态.     

浅析新型分子筛材料的性能及检验方法—4A分子筛的标准化

4A分子筛作为一种新型材料,具有很好的吸附、分离、分散等性能,广泛应用于化工、涂料、日化、汽车及现代医学等领域。由于涉及领域较多,新修订的HG／T2524—2010《4A分子筛》标准在使用过程中可能会遇到一些问题。本文对该标准进行了解读与介绍,包括主要技术性能和检验方法,可以帮助各领域标准应用者正确运用标准,以达到预期目的。     

聚丙烯发泡粒子在水处理中的应用

本文对生物滤池填料的选择进行了研究,对几种填料物理性质、填料非生物因素吸附CODCr、填料静态挂膜和以模拟城市生活污水(COD值在150~250)为处理对象,采用自制的简易生物滤池,模拟曝气生物滤池运行参数,对新型生物填料进行去除有机物和氨氮的试验研究。实验表明,研究选用的生物滤料具有较好的孔隙率(99.6%),但表面粗糙度和密度都较小不利于生物膜的附着,滤料荷电性等表面性质也不利于微生物成长。在进水pH 7~8,DO维持在8~9mg/L的情况下,虽然COD和NH4-N去除率最高达到70%~80%,但稳定状态难以保持。因此,聚丙烯材料填料在未改变其发泡和加工工艺前难以满足曝气生物滤池工艺的需要。     

啤酒酵母吸附Cu^2＋的研究

本研究用啤酒酵母茵作为生物吸附剂吸附Cu^2＋,比较分析了培养12h和144h啤酒酵母吸附Cu^2＋过程中的接触时间、pH及Cu^2＋初始浓度三个影响因素。研究结果表明：培养144h的啤酒酵母吸附效果优于12h，其最佳吸附条件为接触时间为30min，pH值为5～6，Cu^2＋初始浓度为80mg·L^-1。     

Incumplimiento del salario mínimo en Europa central y oriental

En este estudio se analiza el incumplimiento del salario mínimo durante el periodo 2003–2012 en diez países de Europa central y oriental con salario mínimo obligatorio nacional. A partir de los datos de EU‐SILC y la metodología propuesta por Bhorat, Kanbur y Mayet (2013), se cuantifica la incidencia y magnitud del incumplimiento. Se realizan análisis de regresión sobre determinantes individuales, laborales y macroeconómicos. Aunque la incidencia permanece relativamente baja, los trabajadores a los que se dirigen las políticas de salario mínimo parecen los más expuestos a su incumplimiento. Con el tiempo, una mayor incidencia se asocia a una razón más alta entre salario mínimo y salario medio.     

Cultural Economy Planning in Creative Cities: Discourse and Practice

While a growing body of research analyses the functional mechanisms of the cultural or creative economy, there has been little attention devoted to understanding how local governments translate this work into policy. Moreover, research in this vein focuses predominately on Richard Florida's creative class thesis rather than considering the wider body of work that may influence policy. This article seeks to develop a deeper understanding of how municipalities conceptualize and plan for the cultural economy through the lens of two cities held up as model ‘creative cities’ — Austin, Texas and Toronto, Ontario. The work pays particular attention to how the cities adopt and adapt leading theories, strategies and discourses of the cultural economy. While policy documents indicate that the cities embrace the creative city model, in practice agencies tend to adapt conventional economic development strategies for cultural economy activity and appropriate the language of the creative city for multiple purposes.     

Input/output ranges and performance: an examination of US machine tool producers

Despite the establishment of high-tech multinational enterprises (MNEs) in Ireland since the late 1950s, the country did not succeed in closing the technological gap with most of its EU counterparts. The weak National System of Innovation (NSI), and in particular low business and government R&D levels, combined with a lack of research and technology linkages between MNEs and indigenous firms, explain these poor results. However, the Shannon region in the West of the country presents some specific institutional characteristics that could theoretically make the region a strong technological enclave. The various actors in the region - i.e. the administrative, financial, political and research institutions, as well as the business organizations - have indeed infused a new type of economic development. After a brief review of the available concepts and models articulated around these actors and their interrelationships, the paper analyses whether the Shannon region, taken as an illustrative example, mirrors a specific economic and technological localized setting. The study is based on a survey of indigenous and foreign firms.     

Sixty years of discrimination and diversity research in human resource management: A review with suggestions for future research directions

This article reviews discrimination and diversity research published in Human Resource Management (HRM) over the past 60 years. While discrimination and diversity are very different constructs, it is often informative to study them together, because when people recognize each other's diversity, this can result in bias, stereotyping, and discrimination. We conducted bibliographic searches for terms related to discrimination and diversity as well as a manual search through every title and abstract published in HRM over the last 60 years to assess article relevance. The search resulted in 135 research articles with 136 unique studies (i.e., samples) which are reviewed in this article. Sex and race are the demographics that have been examined the most in HRM, while religion has been examined the least. Moreover, the number of studies examining lesbian, gay, bisexual, transgender, and queer (LGBTQ) employees in the workplace in HRM has grown quickly within the past 10 years, culminating in a recent meta‐analysis. Our review looks at some of the earliest research published, the most recent research published, and the overall trends we identified in the research over the years for both discrimination and diversity articles. We then make future research suggestions and recommendations to advance the study of discrimination and diversity in the coming years.     

The Early History of the Cumulants and the Gram-Charlier Series

The early history of the Gram-Charlier series is discussed from three points of view: (1) a generalization of Laplace's central limit theorem, (2) a least squares approximation to a continuous function by means of Chebyshev-Hermite polynomials, (3) a generalization of Gauss's normal distribution to a system of skew distributions. Thiele defined the cumulants in terms of the moments, first by a recursion formula and later by an expansion of the logarithm of the moment generating function. He devised a differential operator which adjusts any cumulant to a desired value. His little known 1899 paper in Danish on the properties of the cumulants is translated into English in the Appendix.     

Capturing the Implications of Services Trade Liberalization

This paper evaluates the impact of service sector trade liberalization on the world economy by a ten-region, eleven-sector CGE model with import embodied technology transfer from developed countries to developing countries. Simulation results show that service sector trade liberalization not only directly affects world service production and trade, but also has significant implications for other sectors in the economy. The major channel of the impact is through inter-industry input-output relations and TFP growth induced from services imported by developing countries from developed countries, which may be embodied with new information and advanced technology.     

City Children and Genderfied Neighbourhoods: The New Generation as Urban Regeneration Strategy

Former industrial cities in the West are employing gentrification as urban policy. In these policies, women and families currently play an important role as gentrification pioneers. In my analysis of Rotterdam in the Netherlands, I propose the term genderfication to understand the gender dimensions of this process. Genderfication refers to the production of space for different gender relations. I analyse Rotterdam's urban planning program for becoming a ‘child‐friendly city’, which entails replacing existing urban dwellings with new, larger and more expensive ‘family‐friendly homes’ as a strategy for urban re‐generation. Urban re‐generation supplements regeneration in the form of material and economic restructuring, and refers to the replacement of part of the current population by a new and better suited generation. The ‘child‐friendly city program’ is considered in tandem with punitive ‘youth policies’.     

Hierarchical Models in Environmental Science

Environmental systems are complicated. They include very intricate spatio-temporal processes, interacting on a wide variety of scales. There is increasingly vast amounts of data for such processes from geographical information systems, remote sensing platforms, monitoring networks, and computer models. In addition, often there is a great variety of scientific knowledge available for such systems, from partial differential equations based on first principles to panel surveys. It is argued that it is not generally adequate to consider such processes from a joint perspective. Instead, the processes often must be considered as a coherently linked system of conditional models. This paper provides a brief overview of hierarchical approaches applied to environmental processes. The key elements of such models can be considered in three general stages, the data stage, process stage, and parameter stage. In each stage, complicated dependence structure is mitigated by conditioning. For example, the data stage can incorporate measurement errors as well as multiple datasets with varying supports. The process and parameter stages can allow spatial and spatio-temporal processes as well as the direct inclusion of scientific knowledge. The paper concludes with a discussion of some outstanding problems in hierarchical modelling of environmental systems, including the need for new collaboration approaches.     

Multinomial distributions applied to random sampling of particulate materials

When sampling a batch consisting of particulate material, the distribution of a sample estimator can be characterized using knowledge about the sample drawing process. With Bernoulli sampling, the number of particles in the sample is binomially distributed. Because this is rarely realized in practice, we propose a sampling design in which the possible samples have a nearly equal mass. Expected values and variances of the sample estimator are calculated. It is shown that the sample estimator becomes identical to the Horvitz–Thompson estimator in the case of a large batch-to-sample mass ratio and a large sample mass. Simulations and experiments were performed to test the theory. Simulations confirm that the round-off error due to the discrete nature of particles is negligible for large sample sizes. Sampling experiments were carried out with a mixture of PolyPropylene (PP) and PolyTetraFluorEthylene (PTFE) spheres suspended in a viscous medium. The measured and theoretical variations are in good agreement.