Cadmium (Cd) is a highly toxic heavy metal for both plants and animals. The presence of Cd in agricultural soils is of great concern regarding its entry into the food chain. Cadmium enters into the soil-plant environment mainly through anthropogenic activities. Compounds of Cd are more soluble than other heavy metals, so it is more available and readily taken up by plants and accumulates in different edible plant parts through which it enters the food chain. A number of approaches are being used to minimize the entry of Cd into the food chain. Proper plant nutrition is one of the good strategies to alleviate the damaging effects of Cd on plants and to avoid its entry into the food chain. Plant nutrients play a very important role in developing plant tolerance to Cd toxicity and thus, low Cd accumulation in different plant parts. In this report, the role of some macronutrients (nitrogen, phosphorus, sulfur and calcium), micronutrients (zinc, iron and manganese), and silicon (a beneficial nutrient) has been discussed in detail as to how these nutrients play their role in decreasing Cd uptake and accumulation in crop plants.

are widely used to trap LiPSs via N-Li + interaction, [4,[26][27][28] meanwhile B doping is demonstrated to improve the performance of S/carbon cathode in Li-S batteries due to the strong interaction between PS anions and positively polarized boron in the porous carbon. [29] Despite the fact that heteroatom doping enhances PSs trapping in the cathodes, the trapping efficiency is still limited due to constrained surface area and low doping ratio. In addition, the poor order and broad size distribution of pores in amorphous porous carbons have become major impediment to uniform sulfur distribution and redeposition. In order to get high doping ratio while ensuring high surface area and ordered pore structure for regular sulfur distribution, Tarascon and co-workers pioneered the use of metal-organic frameworks (MOFs) as host materials for sulfur storage, taking advantage of the weak binding between the PSs and the oxygenated framework. [30] Moreover, Zheng et al. [31] and Zhou et al. [32] also reported the Lewis acid-base interactions between PSs and MOFs, which helped decreasing shuttle effect. Nevertheless, the utilization of MOFs is still limited by their poor thermal stability and heavy metal sites, which increase the density of host and thus decrease the energy density of batteries. Recently, Liao et al. proposed utilization of N-doped covalent organic framework (COF) (CTF-1), an organic porous material with low density, small pore size, and large surface area, as host material for sulfur storage. [33] However, this N-doped COF shows only moderate PSs trapping efficiency due to lack of strong interaction between PSs and N-rich pore surface. Considering COFs are porous materials that allow precise control of pore size and surface, as well as homogeneous impregnation of active species in the pores, there is great opportunity to rationally design effective COFs as hosts to store sulfur and fully confine the mobile redox PS species. Although, Lee and co-workers have recently adopted the composite structure of microporous COF-1 grown on mesoporous carbon nanotube as a new interlayer for chemical trapping of PSs in Li-S batteries, the introduction of carbon nanotubes can give rise to complexity to fully probe the electrochemical properties of COFs. [34] Till now, the positive B and negative O double doped boronate ester COFs have never been used as sulfur hosts in Li-S batteries, which is a distinctly different conception from interlayer use.Here, we suggest using boronate ester COFs as the improved trapping matrices for enhanced adsorption of LiPSs. The high density and uniform distribution of positively polarized B and negatively polarized O within the pores guarantee simultaneous adsorption of S x 2− and Li + in soluble LiPSs and thus render sulfur redeposition more uniform. As a result, this new host shows unprecedentedly strong adsorption ability and hence efficiently traps LiPSs within the cathodes. Such unique feature distinguishes boronate ester COF system from other N-doped As one of the most promising energy...

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Four methods, fast titration, salt addition, mass titration, and ζ potentiometry, were employed to determine the point of zero charge (PZC) and isoelectric point (IEP) of NiO. However, this work mainly focuses on the fast titration method because it limits the release of Ni from the substrate. Furthermore, the fast titration is simple, rapid, and accurate and requires a small quantity of substrate as compared to the salt addition and mass titration techniques. The similarity between the PZC and IEP values rules out the specific adsorption of the bulk electrolyte onto the NiO surface. However, the PZC values shift downward with the increase in Cd ion concentration, which indicates the specific adsorption of Cd onto the NiO. In addition, temperature has a mild effect on the deprotonation constants and PZC of NiO. It was also observed that the thermodynamic parameters favor the deprotonation of NiO. ' MATERIALS AND METHODSMaterials. Analytical grade reagents were used in this study. All glassware and polyethylene bottles were rinsed with 10%