Interfacial negative magnetization in Ni encapsulated layer-tunable nested MoS2 nanostructure with robust memory applications.

Combining interfacial interactions and layer-number tunability, the evolution of magnetism in low-dimensional diamagnetic systems like MoS2 is indeed an interesting area of research. To explore this, Ni nanophases with an average size of 12 nm were encapsulated in MoS2 and the magnetization dynamics were studied over the temperature range of 2-300 K. Surprisingly, the newly formed hybrid nanostructure was found to have a negative magnetization state with giant exchange bias that showed a reversible temperature-induced increase in both spin magnetic moment and coercivity. Density functional theory calculations proved an interfacial charge transfer interaction with a spin-polarized density of states. The magnetization state, along with giant exchange correlation among the magnetic clusters, suggested the possibility of robust thermomagnetic memory. The dc magnetization and relaxation, investigated with different measurement protocols, unveiled robust thermoremanent magnetization as a memory effect. The time-dependent magnetization study indicated that contributions from the negative magnetization state along with charge transfer induced spin states are responsible for the memory effect, which can be controlled by both temperature and external field.

A potent cadmium bioaccumulating Enterobacter cloacae strain displays phytobeneficial property in Cd-exposed rice seedlings.

In agricultural soil, cadmium (Cd) pollution compromises soil health, reduces crop yield, and produces Cd-contaminated crops. Bio-based approaches are necessary as an eco-friendly and sustainable solution to mitigate Cd-polluted areas. A heavy metal-resistant rhizobacterial strain (AS10) has been isolated from a heavy metal-defiled rice field. The 16S rDNA sequence and MALDI-TOF MS analyses of ribosomal protein reveal its identity closely similar to Enterobacter cloacae. The strain was found to withstand up to 4000 µg/ml Cd2+, 3312 µg/ml Pb2+ and 1500 µg/ml As3+. The Cd2+ removal efficiency was recorded as high as 72.11% when grown in 4000 µg/ml Cd2+. The strain's Cd-accumulation efficiency was also apprehended by TEM-EDAX followed by XRD-XRF-FTIR analyses. Besides, the strain showed solubilization of inorganic phosphate, ACC deaminase activity, nitrogen fixation and IAA production ability. Added further, the strain, as an efficient bioinoculant, significantly improved rice plant growth at the seedling stage through Cd immobilization. It prevented the surge of stress ethylene and oxidative stress in rice seedlings, resulting in overall plant growth improvement. Hence, the strain AS10 as potent plant growth-promoting rhizobacteria (PGPR) may be beneficial, especially in heavy metal-contaminated crop fields.

Charge-transfer-induced 2D ferromagnetism and realization of thermo-remnant memory effect in ultrathinß-NiOOH-encapsulated graphene.

For graphene-based 2D materials, charge transfer at the interface between graphene and ferromagnetic metal leads to many intriguing phenomena. However, because of the unidirectional spin orientation in ferromagnetic transition metals, interface interaction plays a detrimental role in diminishing the magnetic parameters on 2D surfaces. To overcome this issue, we have synthesized ultrathin 2D weak antiferromagneticß-NiOOH layers on a graphene surface. By exploiting the charge transfer effect and tuning the thickness of the thinß-NiOOH layers, conversion of ferromagnetism along with giant coercivity and the thermo-remnant magnetic memory effect were observed. As antiferromagnets have two spin orientations, transfer of charge at the interface breaks the nullifying effect of zero magnetization in antiferromagnets and the combined system behaves like a 2D ferrimagnet. Whenever, the sandwich structure ofß-NiOOH/graphene/ß-NiOOH is formed, it also shows interlayer exchange coupling those results in huge exchange bias and anomalous temperature dependence of coercivity. Due to the strong exchange interaction between the layers, the combined system also shows a robust temperature-based memory effect. Spin-polarized density functional theory was also calculated to confirm the interface interaction and its quantitative evaluation by means of Bader charge analysis and charge-density mapping.

Abatement of arsenic-induced phytotoxic effects in rice seedlings by an arsenic-resistant Pantoea dispersa strain.

Population detonation and rapid industrialization are the major factors behind the reduction in cultivable land that affects crop production seriously. This situation is further being deteriorated due to the negative effects of abiotic stresses. Under such conditions, plant growth-promoting rhizobacteria (PGPR) are found to improve crop production which is essential for sustainable agriculture. This study is focused on the isolation of potent arsenic (As)-resistant PGPR from the agricultural land of West Bengal, India, and its application to reduce As translocation in rice seedlings. After screening, an As-resistant PGPR strain AS18 was identified by phenotypic characters and 16S rDNA sequence-based homology as Pantoea dispersa. This strain displayed nitrogen fixation, phosphate solubilization, 1-aminocyclopropane-1-carboxylic acid deaminase (ACCD) activity, indole-3-acetic acid (IAA) production, in addition to As (III) resistance up to 3750 µg/mL. The As removal efficiency of this strain was up to 93.12% from the culture medium as evidenced by AAS. The bioaccumulation property of AS18 strain was further validated by TEM-EDAX-XRD-XRF-FTIR studies. This strain showed significant morpho-biochemical improvements including antioxidant enzymatic activities and As-minimization in plant (rice) cells. Thus, being an As-resistant potent PGPR, AS18 strain is expected to be applied in As-spiked agricultural fields for bioremediation and phytostimulation.