Adsorption Properties of Waste Building Sludge for Environmental Protection

Waste building sludge (WBS) originating in the production of concrete prestressed poles (CSW) and technical stone (TSW) used in original and Fe-modified forms (CSWFe, TSWFe) was tested as an environmentally friendly and cheap sorbent of selected cations (Cd2+, Pb2+, Cs+) and anions (AsO43−, PO43−, CrO42−) from water. The experiments were performed with 0.1 and 0.5 mmol·L−1 model solutions in a batch manner at laboratory temperature. Adsorption data were fitted with the Langmuir model. The adsorption of cations (Pb2+ and Cd2+) ran almost quantitatively (>97%) on both CSW and TSW. Cesium (Cs+) adsorption on TSW reached 80%, while in the case of CSW, it was ineffective. The modification of CSW and TSW with FeII (CSWFe and TSWFe) improved their adsorption selectivity to anions by up to 70%. The adsorption of PO43− and AsO43− ran quantitatively (>98%) on modified CSWFe and TSWFe and also on initial CSW, while CrO42− was effectively adsorbed (≈80%) on TSWFe only. The adsorption affinity of tested ions in terms of adsorption capacity and sorbent consumption declined in order as follows: Pb2+ ≈ Cd2+ >> Cs+ for cations and AsO43− ≈ PO43− > CrO42− for anions.

Persistence and Effectiveness of Diatomaceous Earth and Spinosad® Against Sitophilus zeamais (Coleoptera: Curculionidae) on Stored Rice

The insecticidal and residual effectiveness of Diatomaceous Earth (DE) (Nigeria-derived) and Spinosad® against Sitophilus zeamais on stored rice were evaluated under laboratory temperature (30 ± 2°C) and relative humidity (70 ± 5%). Adult mortality and progeny emergence were studied at three dose rates of DE and Spinosad® (0.1g/kg, 0.5g/kg, and 1g/kg). Spinosad® at 0.1-1.0 g/kg dose rates demonstrated significant results in mortality compared to DE and control groups at 14 d post-treatment and after the 2nd month of storage treatment. Spinosad® treated grains at the same dose rates also resulted in a significant reduction (P<0.05) in the emergence of progeny. Unlike DE, Spinosad® showed some insecticidal efficacy against S. zeamais on storage.

Evaluation of the larvicidaleffectof the essential oils extracted from five aromatic plants of Algeria: test on the miteTineola bisselliella (Lepidoptera:Tineidae)

The essential oils extracted by hydrodistillation from fivearomatic plants from Algerian West –Ammoїdes verticillata (Apiacae), Origanum glandulosum (Lamiacae), Thymus capitatus (Lamiacae), Rosmarinus officinalis (Lamiacae), Artemisia herba-alba (Asteracae), were tested with various amounts on the larvaeof Tineola bisselliella, under the conditions of laboratory (Temperature of 26°C and with a relative humidity of 75 %). These oilscaused a significant larvicidalactivity. The essential oils extracted from Artemisia herba-alba, Rosmarinus officinalis, Origanum glandulosum are most toxic with LD50of 5,92μL/50,24cm², 6,66μL/50,24cm², and 7,16μL/50,24cm² respectively, Ammoїdes verticillata present alittle variable toxicity with LD50= 7,95μL/50,24cm², whereas the essential oil of Thymus capitatus is the least toxic on the larves of T. bisselliella with one LD50de 9,81μL/50,24cm².The analysis of the chemical composition shows the richness of five essential oils in compounds known for their insecticidal properties like α-pinène, β-pinène, p-cymène, carvacrol, camphre, γ-terpinène, and1,8-cineole, what explains the results obtained.

Evaluation of Ethyl Formate, Phosphine, and Their Combination to Disinfest Harvested Celery against Purple Scum Springtails

Export celery (Apium graveolens var. dulce) from Australia has been affected by a natural infestation of purple scum springtails (Hypogastrura vernalis). These insects live inside the celery head, contaminating fresh celery, but do not cause any visible damage. As a result, purple scum springtail-infested celery has led to rejection for export with an impact on market value for fresh produce. In this study, fumigation with ethyl formate (EF), phosphine (PH3), and their combination on mortality of purple scum springtails in naturally infested celery was evaluated. Laboratory experiments were conducted using concentrations of 50, 60, and 90 mg·L−1 of EF for 1, 2, and 4 hours; 1, 1.5, 2, and 2.5 mg·L−1 of PH3 for 2, 4, and 6 hours; and 20, 30, and 40 mg·L−1 of EF combined with 1 mg·L−1 of PH3, for 2 and 4 hours at the laboratory temperature 25 °C. Complete control was achieved at 90 mg·L−1 of EF for 2 hours; however, phytotoxicity was observed in celery treated by EF at all concentrations. PH3 at 2.5 mg·L−1 achieved 100% mortality within 6 hours, and no phytotoxicity was evident. Mortality of 100% was achieved also at 30 and 40 mg·L−1 EF combined with 1 mg·L−1 of PH3 for 2 and 4 hours exposure time; however, phytotoxicity occurred with EF alone treatments and with the combination. From these data, we conclude that PH3 alone has potential as a fumigant for the preshipment treatment of celery infested with purple scum springtails.

Rapid preparation of self-assembled CdTe quantum dots used for sensing of DNA in urine

In this article, the authors report a systematic study of the self-assembly of CdTe quantum dots (QDs) stabilized by mercaptosuccinic acid (MSA) at laboratory temperature (25 °C) or after thermal treatment (90 °C).