The stronger bond

Covalent compounds melt at lower temperatures than polar compounds. Does this mean that covalent bonds are weaker than ionic bonds

Luminescent Silver Clusters with Covalent Functionalization of Graphene

Brightly luminescent, atomically precise subnanometer clusters of silver protected by glutathione were covalently functionalized by solution phase thiolated graphene using ligand exchange. A hybrid molecule was formed, which was obtained in a nearly pure form by phase transfer from the aqueous to the organic phase. The resulting hybrid exhibited properties of both of these nanoscale materials. UV–vis, luminescence, XPS, EDAX, TEM, and Raman spectroscopy were used to characterize the hybrid structure, which showed the spectroscopic characteristics of both the constituents. The luminescence of the cluster was retained in the hybrid, along with features characteristic of graphene. Atomically precise clusters with covalently linked graphene will be useful for new applications in the areas of drug delivery, sensors, and catalysis

On the position of La, Lu, Ac and Lr in the periodic table: a perspective

The periodic table of elements, organised as blocks of elements that contain similar properties, occupies a central role in chemistry. However, the position of some of the elements in the periodic table is a debate that has been ensuing over the past one and a half long centuries. Particularly, the positions of lanthanum (La), lutetium (Lu), actinium (Ac) and lawrencium (Lr) in the periodic table have been quite controversial. Different kinds of studies carried out by various research groups have yet left the fate of these elements undecided as the results of these investigations suggested that these elements could potentially be placed in the d-block, p-block or all four in the f-block. Our recent work looked into this question from a new perspective, involving encapsulation of La, Lu, Ac and Lr into Zintl ion clusters, Pb-12(2-) and Sn-12(2-). These clusters were chosen as they provide a fitting environment for the determination of structural, thermodynamic and electronic properties of the encapsulated species. Various results that have been evaluated and subsequently analysed (Joshi et al. in Phys. Chem. Chem. Phys. 20:15253-15272, 2018) in order to seek out similarities and differences for making justified conclusions about the placement of all these four elements in the periodic table are the subject matter of this review article

Phosphorus-Induced One-Step Synthesis of NiCo₂S₄ Electrode Material for Efficient Hydrazine-Assisted Hydrogen Production

Rational control of the reaction parameters is highly important for synthesizing active electrocatalysts. NiCo2S4 is an excellent spinel-based electrocatalyst that is usually prepared through a two-step synthesis. Herein, a one-step hydrothermal route is reported to synthesize P-incorporated NiCo2S4. We discovered that the inclusion of P caused formation of the NiCo2S4 phase in a single step. Computational studies were performed to comprehend the mechanism of phase formation and to examine the energetics of lattice formation. Upon incorporation of the optimum amount of P, the stability of the NiCo2S4 lattice was found to increase steadily. In addition, the Bader charges on both the metal atoms Co and Ni in NiCo2S4 and P-incorporated NiCo2S4 were compared. The results show that replacing S with the optimal amount of P leads to a reduction in charge on both metal atoms, which can contribute to a more stable lattice formation. Further, the electrochemical performance of the as-synthesized materials was evaluated. Among the as-synthesized nickel cobalt sulfides, P-incorporated NiCo2S4 exhibits excellent activity toward hydrazine oxidation with an onset potential of 0.15 V vs RHE without the assistance of electrochemically active substrates like Ni or Co foam. In addition to the facile synthesis method, P-incorporated NiCo2S4 requires a very low cell voltage of 0.24 V to attain a current density of 10 mA cm–2 for hydrazine-assisted hydrogen production in a two-electrode cell. The free energy profile of the stepwise HzOR has been investigated in detail. The computational results suggested that HzOR on P-incorporated NiCo2S4 was more feasible than HzOR on NiCo2S4, and these findings corroborate the experimental evidence

Detection of high frequency of mutations in a breast and/or ovarian cancer cohort: implications of embracing a multi-gene panel in molecular diagnosis in India

Breast and/or ovarian cancer (BOC) are among the most frequently diagnosed forms of hereditary cancers and leading cause of death in India. This emphasizes on the need for a cost-effective method for early detection of these cancers. We sequenced 141 unrelated patients and families with BOC using the TruSight Cancer panel, which includes 13 genes strongly associated with risk of inherited BOC. Multi-gene sequencing was done on the Illumina MiSeq platform. Genetic variations were identified using the Strand NGS software and interpreted using the StrandOmics platform. We were able to detect pathogenic mutations in 51 (36.2%) cases, out of which 19 were novel mutations. When we considered familial breast cancer cases only, the detection rate increased to 52%. When cases were stratified based on age of diagnosis into three categories,. 40 years, 40-50 years and >50 years, the detection rates were higher in the first two categories (44.4% and 53.4%, respectively) as compared with the third category, in which it was 26.9%. Our study suggests that next-generation sequencing-based multi-gene panels increase the sensitivity of mutation detection and help in identifying patients with a high risk of developing cancer as compared with sequential tests of individual genes