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Phosphonates are widely used in various industries. It is desirable to remove them before discharging phosphonate-containing wastewater. This study describes a large number of batch experiments with adsorbents that are likely suitable for the removal of phosphonates. For this, adsorption isotherms for four different granular ferric hydroxide (GFH) adsorbents were determined at different pH values in order to identify the best performing material. Additionally, the influence of temperature was studied for this GFH. A maximum loading for nitrilotrimethylphosphonic acid (NTMP) was found to be ∼12 mg P/g with an initial concentration of 1 mg/L NTMP-P and a contact time of 7 days at room temperature. Then, the adsorption of six different phosphonates was investigated as a function of pH. It was shown that GFH could be used to remove all investigated phosphonates from water and, with an increasing pH, the adsorption capacity decreased for all six phosphonates. Finally, five adsorption–desorption cycles were carried out to check the suitability of the material for multiple re-use. Even after five cycles, the adsorption process still performed well.

This article sets up a dialogue between two bodies of ancient texts, i.e. Jewish wisdom literature and Greco-Roman didactic of the Hellenistic period, with an awareness of the scholarly and interpretive communities that have studied, taught and transformed these bodies of texts from antiquity until the present. The article does not claim direct influence or cross-pollination across intellectual, religious or social communities in the Hellenistic period. Instead, the article suggests four discrete frameworks for thinking about comparative antiquity: creation, the law, the sage and literary form. The comparative model proposed here intends to create the conditions for noticing parallels and kindred concepts. However, the article resists the temptation to repeat earlier scholarly arguments for dependency or priority of influence. Instead, the essay demonstrates remarkable alignments, suggestively similar developments, and synergies. Perhaps, the ideal first reader for this article is none other than Philo of Alexandria.

This paper introduces a procedure to investigate the adsorption of phosphonates onto iron-containing filter materials, particularly granular ferric hydroxide (GFH), with little effort and high reliability. The phosphonate, e.g., nitrilotrimethylphosphonic acid (NTMP), is brought into contact with the GFH in a rotator in a solution buffered by an organic acid (e.g., acetic acid) or Good buffer (e.g., 2-(N-morpholino)ethanesulfonic acid) [MES] and N-cyclohexyl-2-hydroxyl-3-aminopropanesulfonic acid [CAPSO]) in a concentration of 10 mM for a specific time in 50 mL centrifuge tubes. Subsequently, after membrane filtration (0.45 µm pore size), the total phosphorus (total P) concentration is measured using a specifically developed determination method (ISOmini). This method is a modification and simplification of the ISO 6878 method: a 4 mL sample is mixed with H2SO4 and K2S2O8 in a screw cap vial, heated to 148-150 °C for 1 h and then mixed with NaOH, ascorbic acid and acidified molybdate with antimony(III) (final volume of 10 mL) to produce a blue complex. The color intensity, which is linearly proportional to the phosphorus concentration, is measured spectrophotometrically (880 nm). It is demonstrated that the buffer concentration used has no significant effect on the adsorption of phosphonate between pH 4 and 12. The buffers, therefore, do not compete with the phosphonate for adsorption sites. Furthermore, the relatively high concentration of the buffer requires a higher dosage concentration of oxidizing agent (K2S2O8) for digestion than that specified in ISO 6878, which, together with the NaOH dosage, is matched to each buffer. Despite the simplification, the ISOmini method does not lose any of its accuracy compared to the standardized method.

Readers have always acknowledged the comparatively clear macrostructure ofDe rerum natura3. It begins with aprooemiumin which is described the terrifying impact which the fear of death has on human lives, as well as the fact that Epicurus has provided a cure against this fear, namely his physical doctrines (1–93). Particular attention is paid to fears of an afterlife in which we have to suffer pain and grief in the underworld; cf., for instance, the programmatic lines 3.37–40 (translation by Ferguson Smith, which will be used throughout):Thisprooemiumis followed by a long passage (94–829) in which Lucretius explains the basics of Epicurean psychology and tries to show that the soul is (like the body) material and hence mortal; this last point is driven home with particular force in II. 417–829 where Lucretius lists twenty-five proofs for the mortality of the soul.

The oldest witnesses for Cicero's Topica are two ninth-century manuscripts belonging to Leiden University Library (Codd. Voss. Lat. F84 and F86, dubbed A and B). The two mss. have been extensively studied in their function as main sources of Cicero's Leg. by P.L. Schmidt. In the best edition of the Topica by G. Di Maria, however, Schmidt's work is ignored, and the purpose of this article is to bring Schmidt's results to bear on what Di Maria has established, and to correct both scholars on some points. Schmidt's view is confirmed that the oldest correction layers in A and B do not reflect readings of a third manuscript and that B was completed in the ninth century by insertion of four additional folia after these correction layers had been produced. Then new information is added on the details of the completion of the text of the Topica in B.

Around 87b.c.during the turmoil of the first Mithridatic war, Philo of Larissa, head of the so-called Fourth Academy, fled from Athens to Rome. There he gave lectures on philosophical topics and taught rhetoric. His classes were attended by a young man called Cicero, who was inspired by him to include in a work on rhetorical theory, somewhat inappropriately, a fervent confession of scepticism to which he stuck for the rest of his life. Later Cicero claimed to be—as an orator—not a product of the workshops of the teachers of rhetoric, but of the spacious walks of the Academy. And he developed the ideal of the philosopher-orator. Scholars disagree whether the idea to bring philosophy and rhetoric together is Cicero's own invention or an adaptation from someone else, for instance Philo.