Modelling the Plant Uptake of Metals from Release Rates Obtained by the EUF Method

In this study, soil dissolution kinetics were evaluated to predict the metal uptake of lettuce plants under varying conditions of fertilisation and metal pollution. Velocities and time dependencies of soil dissolution obtained by electro-ultrafiltration (EUF), which prevents back reaction, were modelled in three ways, obtained from suspensions in 0.002 M DTPA at determined soil pH levels, for cases in which sampling versus time led to decreasing concentrations. The models yielded a maximum achievable concentration, a timespan needed for it to be reached, a slope, and an intercept of the respective fitted curves. Three geogenically metalliferous soil samples and one ambient soil sample, both as originals, fertilised with PK or soaked with a Cd-Ni-Pb solution, were used as solid samples. The resulting kinetic parameters were correlated with the amounts absorbed by lettuce plants grown with these substrates in pot experiments, which yielded fairly good correlations with Zn, but also with Li and Sr, as well as Ni and Pb, mainly because of differences due to the addition of a metallic salt solution. Plant growth was hardly influenced by the additions.

ENHANCEMENT OF DYE ABSORPTION OF COTTON FABRIC THROUGH OPTIMIZATION OF BIOPOLYMER TREATMENT

"Environmental pressure is pushing towards the ‘green’ alternatives to synthetic or petro-chemically derived products. Biopolymers are replacement materials suitable for different chemical processes. The surface modification of textile fibres using biopolymers is considered as the best route for modern textile treatments, to minimize the generation of wastewater containing salts, unfixed dye and other chemicals, which may affect the environment and human health. To avoid these problems, the pretreatment of cotton with biopolymers is a safe option in eco-friendly dyeing. In the present work, chitosan was selected for application on cotton textile for improving its dyeing efficiency with natural dye (onion skin). Chitosan is a versatile polycationic polysaccharide possessing hydroxyl and amino functional groups, which can easily be fabricated with desired functional properties. The chitosan treatment was standardized on the basis of dyeing properties, such as percent dye absorption, colour strength (K/S) and wash fastness. When the chitosan treatment was applied with optimized parameters, it was found that the chitosan treated onion skin dyed fabric showed higher dye absorption (66.17%), colour strength (16.52) and wash fastness rating than the alum treated dyed fabric. Thus, the chitosan treatment enhanced the dyeing properties of cotton fabric towards the application of natural dye (onion skin), without using any metallic salt. To conclude, the chitosan treatment is a safe and environmentally benign route to improve the natural dye absorption of cotton fabrics."

Bionanotechnology: Silver Nanoparticles Supported on Bovine Bone Powder Used as Bactericide

Bionanotechnology is a relatively new term that implies the use of some biological material or organisms in order to prepare nanosystems or nanoparticles. This work presents the preparation and bactericide application of a sustainable nanometric system (silver nanoparticles) using a waste biological support (bovine bone powder). This system was prepared by the method of metallic salt reduction, using NaBH4 as reducing agent and AgNO3 as metallic salt. Two silver contents were analyzed, 1% and 5% weight. The latter was found to be more efficient than the former. Transmission electronic microscopy shows an average size of 10.5 ± 3.3 nm and quasi-sphere morphology. The antimicrobial assay shows that a 5% weight content of silver had a bactericide effect for Escherichia coli at 46.8 min of exposure. The minimum inhibitory concentration (MIC) of silver nanoparticles supported on bovine bone powder for Escherichia coli was 7.5 µg/mL. The biocomposite exhibits a specific antibacterial kinetics constant (k) of 0.1128 min−1 and decimal reduction time (DRT) of 20.39 min for Escherichia coli. Thus, it was concluded that a biocomposite was prepared with a biodegradable, waste, and low-cost support, under mild conditions (room temperature and atmospheric pressure) and using water as solvent.

Synthesis and crystal structure of [Cs([2.2.2]crypt)]2[Mo(CO)5]

Reduction of the heteroleptic metal carbonyl complex Mo(CO)3(η5-Cp)H with the metallic salt Cs5Bi4 in the presence of [2.2.2]crypt (= 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) in liquid ammonia led to single crystals of bis[(4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane)caesium] pentacarbonylmolybdate, [Cs(C18H36N2O6)]2[Mo(CO)5] or [Cs([2.2.2]crypt)]2[Mo(CO)5]. The twofold negatively charged anionic complex corresponds to the 18 valence electron rule. It consists of an Mo atom coordinated by five carbonyl ligands in a shape intermediate between trigonal–bipyramidal and square-pyramidal. The Mo—C distances range from 1.961 (3) to 2.017 (3) Å, and the C[triple-bond]O distances from 1.164 (3) to 1.180 (4) Å.

Metallic salt-catalyzed direct indium insertion into alkyl iodides and their applications in cross-coupling reactions

An efficient method for the synthesis of alkyl indium reagents via an indium(iii) or lead(ii) halide-catalyzed direct insertion of indium into alkyl iodides is developed. NMR and ESI-MS analyses indicated the formation of a mixture of an alkyl indium dihalide (RInX2) and a dialkyl indium halide (R2InX).

Correction: Freezing temperature controlled deep eutectic solvent dispersive liquid–liquid microextraction based on solidification of floating organic droplets for rapid determination of benzoylureas residual in water samples with assistance of metallic salt

Correction for ‘Freezing temperature controlled deep eutectic solvent dispersive liquid–liquid microextraction based on solidification of floating organic droplets for rapid determination of benzoylureas residual in water samples with assistance of metallic salt’ by Miyi Yang et al., RSC Adv., 2017, 7, 56528–56536.

Cationisation of Alginate Fiber to Improve the Dyeing Properties Using Natural Dyes from Rhubarb: A New Approach

In this investigation dyeing of alginate fiber was carried out after cationic treatment of EPTAC (2, 3-Epoxypropyl Trimethyl Ammonium Chloride). Optimum dyeing process and parameter show good dyeing performance when alginate fiber dyed with rhubarb dye. In addition to cationic treatment is taken into account for alginate fiber to improve fastness, color strength, breaking strength. Later in dyeing for fixation ferrous sulfate, copper sulphate was considered as mordents. Moreover using pre-mordanting methods conveyed the dyeing of alginate fiber with the stave of metallic mordant and without metallic salt mordents. The evaluation of each color dyed material was done through following two terms for instance CIELAB (L*, a*, and b*) and K/S values. According to AATCC test methods color fastness to washing of the dyed fiber was determined whereas according to the ASTM D3822M standard the breaking strength of alginate fiber was estimated and tested. When dyeing was carried out on alginate fiber through considering optimum parameter like 80◦C for 90 min, M: L 1:40 and at pH 7 which showed optimum results. In addition to mostly very good wash fastness was obtained while there was no fading of the color, whereas the moderate level of color fastness to crocking was achieved. Later after dyeing the evaluations of SEM of the cationized alginate fiber and FTIR of powder from the rhubarb dye were observed. The results suggested that the surface of cationized alginate fiber was smoother than the raw alginate fiber.