Waste-Derived Siliceous Materials as a Novel Sorbent for Removal of Ni2+ from Aqueous Solutions

In the present study, the preparation of sorbent from waste-derived siliceous materials has been investigated for the removal of nickel ion (Ni²⁺) from aqueous solutions. Three types of ashes, i.e., rice husk ash (RHA), palm oil fuel ash (PFA), and coal fly ash (CFA), were used in the preparation of sorbent. Batch studies were carried out to examine the effect of various experimental parameters, i.e., RHA/CFA/PFA ratio in the sorbent preparation, contact time, initial concentration of Ni²⁺, agitation rate, and pH. Among all the ratios of the prepared sorbent, it was found that sorbent containing RHA and PFA gave the highest Ni²⁺ removal efficiency. The optimum conditions for Ni²⁺ removal using RHA/PFA sorbent were obtained at contact time of 30?min, Ni²⁺ concentration of 100?mg/L, agitation rate of 130?rpm, and pH?4. During the optimum condition, more than 90% of Ni²⁺ could be removed in all experiment studies. It was also found that the spent RHA/PFA sorbents had a narrow range of particle size distributions as compared to prepared RHA/PFA sorbent. In addition, the surface morphology of the spent RHA/PFA sorbents had more compact structures.     

The use of machine learning methods in classification of pumpkin seeds (Cucurbita pepo L.)

Genetic Resources and Crop Evolution - Pumpkin seeds are frequently consumed as confection worldwide because of their adequate amount of protein, fat, carbohydrate, and mineral contents. This study...     

Effect of magnesium fertilization on yield and leaf composition of tomato plants

Tomato plants were grown for 2 years at 4 different rates of Mg fertilization on a Princeton loamy sand at pH 4.8 with 29 kg exchangeable Mg/ha. Calcareous limestone was used to provide a pH treatment in the second year. Magnesium deficiency symptoms were observed on plants grown on plots having ≤ 38 kg/ha NH₄OAC‐extractable Mg. Application of 56 kg Mg/ha corrected Mg deficiency and produced a significant increase in yield. Application of calcitic limestone also produced significant yield increases, but did not affect the development of Mg deficiency symptoms. Tomato yield was increased 27.9% by Mg application and 17.7% by lime application. Highest tomato yield was obtained with application of 112 kg Mg/ha. Symptoms of Mg deficiency were observed when the Mg concentration in recently mature leaf tissue was in the 0.30 to 0.32% range. Magnesium concentration in leaf tissue increased linearly with increasing Mg rate. Leaf Mg concentration at various growth stages of the tomato plant was variable depending on Mg treatment. Magnesium fertilization rate bad little effect on Ca or K leaf concentrations. Application of Calcltic limestone increased leaf tissue Ca and reduced leaf tissue Mg and Mn concentrations.     

Visible-Light-Driven Photocatalytic N-Doped TiO<Subscript>2</Subscript> for Degradation of Bisphenol A (BPA) and Reactive Black 5 (RB5) Dye

Bisphenol A (BPA) and reactive black 5 (RB5) dye are among the most persistent and non-biodegradable contaminants in water which require an urgent need for the development of effective removal method. The ubiquitous existence of both contaminants could interfere with the human health and aquatic environmental balance. Photocatalytic process as one of advanced oxidation processes (AOPs) has shown high performance for degradation of organic compounds to the harmless materials under sensible condition. Therefore, this study aims to develop a visible-light-driven photocatalyst that can efficiently degrade BPA and RB5 present in household water. N-doped TiO₂ were successfully synthesized via simple and direct sol–gel method. The prepared TiO₂ nanoparticles were characterized by field emission scanning microscope (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and Brunauere Emmette Teller (BET) analysis. The incorporation of nitrogen in TiO₂ lattice exhibited excellent optical responses to visible region as revealed by UV–Vis–NIR spectroscopy absorption capability at 400–600 nm. The photocatalytic activity of the N-doped TiO₂ nanoparticles was measured by photocatalytic degradation of BPA and RB5 in an aqueous solution under visible-light irradiations. Degradation of BPA and RB5 was 91.3% and 89.1%, respectively after 360 min illumination. The degradation of BPA and RB5 by N-doped TiO₂ was increased up to 89.8% and 88.4%, respectively under visible-light irradiation as compared to commercial TiO₂ P25. This finding clearly shows that N-doped TiO₂ exhibits excellent photocatalytic degradation of BPA and RB5 under visible irradiation, hence have a promising potential in removing various recalcitrant contaminants for water treatment to fulfill the public need to consume clean water.

Open image in new window

Graphical Abstract ?

     

Phenotypic diversity and evolution of farmer varieties of bread wheat on organic farms in Europe

The contribution of farmers to the creation and maintenance of genetic diversity is beginning to receive more recognition in developed countries. Although the use of landraces and historic varieties has largely disappeared in countries with industrialized agricultural systems and formal seed markets, certain varieties with particular cultural significance have been continuously cultivated by farmers and other varieties have been preserved ex situ in genebanks. Recently, associations of organic farmers have become involved in the conservation and use of landraces and historic varieties (called farmer varieties in this article) because these varieties possess agronomic and quality traits that they have not found in modern varieties. In this study, eight farmer varieties of bread wheat from Europe selected by participating farmers were evaluated in on-farm trials during 3 years of cultivation. Each variety was grown on each farm, and phenotypic changes in each variety were measured the third year in a replicated split-plot trial on each farm comparing the version of each variety the farmer had multiplied to a sample of each variety from the region of origin. All varieties, including the two modern pureline varieties used as checks, showed statistically significant phenotypic changes over 3 years of multiplication. However, the magnitude of these changes was moderate and did not call into question varietal identity or distinctness. In addition, some traits of putative agronomic and adaptive importance, such as grain weight per spike and thousand kernel weight, did not respond positively to natural selection (environmental conditions and management practices) which suggests the necessity of farmer selection to maintain and improve varietal performance.     

Effects of Farm Yard Manure and Lime on Cadmium Uptake by Rice Grown in Two Contaminated Soils of Chittagong

A pot experiment was conducted to evaluate the efficiency of farm yard manure （FYM） and lime （calcium carbonate） on reducing the uptake of Cd by rice in two Cd contaminated soils of Chittagong. The effects of farm yard manure, lime and farm yard manure mixed with lime （FYM ＋ Lime） on rice （Oryza sativa L.） growth, Cd uptake by rice and 0.1 N HC1 extractable Cd in soil were investigated. Results showed that addition of lime and farm yard manure mixed with lime significantly decreased 0.1 N HCl extractable Cd in the city sewage soil. Application of farm yard manure significantly decreased Cd concentration in rice in the city sewage soil. Lime and farm yard manure mixed with lime significantly reduced Cd concentration in rice m both the contaminated soils. Lime was more efficient than farm yard manure in reducing the uptake of Cd by rice.