Influence of sludge retention time on filtration performance and biomass characteristics in a hollow fiber membrane bioreactor

In this study, the filtration process and the biomass characteristics in a laboratory-scale submerged membrane bioreactor (MBR) equipped with a hollow fiber (HF) microfiltration membrane were studied at different solid retention times (SRT). The MBR was fed by synthetic wastewater and the organic loading rate (OLR) was 0.5, 0.2, 0.1, and 0.08 kg COD kg VSS−1 d−1 for 10, 30, 60, and 90 days of SRT, respectively. The hydraulic retention time was 8.4 h and the permeate flux was 6 L m−2 h−1(LMH). Data analysis confirmed that at all the studied SRTs, the HF-MBR operated very good obtaining of high quality permeates. Chemical Oxygen Demand (COD) removal efficiencies were higher than 95%. The best filtration performance was reached at SRT of 30 d. On the other hand, the respirometric analysis showed that biomass was more active and there was more biomass production at low SRTs. The concentration of soluble extracellular polymeric substances (EPS) decreased with increasing SRT. A decrease of soluble EPS caused a decrease of membrane fouling rate, decreasing the frequency of chemical cleanings. The floc size decreased with SRT increasing. At high SRTs, there was more friction among particles due to the increase of the cellular density and the flocs broke decreasing their size.

The Political and Judicial Life of Metadata: Digital Rights Ireland and the Trail of the Data Retention Directive. CEPS Paper in Liberty and Security No. 65, May 2014

This paper examines the challenges facing the EU regarding data retention, particularly in the aftermath of the judgment Digital Rights Ireland by the Court of Justice of the European Union (CJEU) of April 2014, which found the Data Retention Directive 2002/58 to be invalid. It first offers a brief historical account of the Data Retention Directive and then moves to a detailed assessment of what the judgment means for determining the lawfulness of data retention from the perspective of the EU Charter of Fundamental Rights: what is wrong with the Data Retention Directive and how would it need to be changed to comply with the right to respect for privacy? The paper also looks at the responses to the judgment from the European institutions and elsewhere, and presents a set of policy suggestions to the European institutions on the way forward. It is argued here that one of the main issues underlying the Digital Rights Ireland judgment has been the role of fundamental rights in the EU legal order, and in particular the extent to which the retention of metadata for law enforcement purposes is consistent with EU citizens’ right to respect for privacy and to data protection. The paper offers three main recommendations to EU policy-makers: first, to give priority to a full and independent evaluation of the value of the data retention directive; second, to assess the judgment’s implications for other large EU information systems and proposals that provide for the mass collection of metadata from innocent persons, in the EU; and third, to adopt without delay the proposal for Directive COM(2012)10 dealing with data protection in the fields of police and judicial cooperation in criminal matters.

Global assessment of soil phosphorus retention potential

Limited availability of P in soils to crops may be due to deficiency and/or severe P retention. Earlier studies that drew on large soil profile databases have indicated that it is not (yet) feasible to present meaningful values for "plant-available" soil P, obtained according to comparable analytical methods, that may be linked to soil geographical databases derived from 1:5 million scale FAO Digital Soil Map of the World, such as the 5 x 5 arc-minute version of the ISRIC-WISE database. Therefore, an alternative solution for studying possible crop responses to fertilizer-P applied to soils, at a broad scale, was sought. The approach described in this report considers the inherent capacity of soils to retain phosphorus (P retention), in various forms. Main controlling factors of P retention processes, at the broad scale under consideration, are considered to be pH, soil mineralogy, and clay content. First, derived values for these properties were used to rate the inferred capacity for P retention of the component soil units of each map unit (or grid cell) using four classes (i.e., Low, Moderate, High, and Very High). Subsequently, the overall soil phosphorus retention potential was assessed for each mapping unit, taking into account the P-ratings and relative proportion of each component soil unit. Each P retention class has been assigned to a likely fertilizer P recovery fraction, derived from the literature, thereby permitting spatially more detailed, integrated model-based studies of environmental sustainability and agricultural production at the global and continental level (< 1:5 million). Nonetheless, uncertainties remain high; the present analysis provides an approximation of world soil phosphorus retention potential.

Latitude 19,̊ a romance of the West Indies in the year of Our Lord eighteen hundred and twenty; being a faithful account and true, of the painful adventures of the skipper, the bo's'n, the smith, the mate, and Cynthia;

Mode of access: Internet.

Catálogo del material escolar enviado á la exposición anexa al IIIer Congreso Internacional de Higiene Escolar, Paris, 2-7 de agosto de 1910 con una noticia sobre la instrucción pública primaria. Catalogue de matériel scolaire présenté á l'exposition annexe au IIIe Congres International d'Hygiene Scolaire, Paris, 2-7 aoút 1910, avec une notice sur l'instruction publique primaire.

Mode of access: Internet.

Le maté, au point de vue agricole, médical, hygiénique, militaire et commercial, avec ses modes de préparation.

Mode of access: Internet.

Yerba mate: the tea of South America ...

"Reprinted from the May, 1916, issue of the Bulletin of the Pan American Union, Washington, D.C."

The trumpet-major, John Loveday : a soldier in the war with Buonaparte, and Robert his brother, first mate in the merchant service : a tale /

Mode of access: Internet.

Compte-rendu de la situation morale et matérielle de la colonie Icarienne, du mois d'août 1857 au mois de février 1858.

With the original coloured wrappers.

Minority recruitment and retention in ARL libraries /

"September 1990."

Factors contributing to the retention of seated passengers during emergency stops. Final report.

Urban Mass Transportation Administration, Washington, D.C.

The effect of biological slime on the retention of alkyl benzene sulfonate on granular media /

Includes bibliographical references (p. 69-71).

Retention efficiencies of charcoal traps for fission gases : technical report /

"August 23, 1957."