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排序方式: 共有307条查询结果,搜索用时 31 毫秒
1.
Dr. Anoop Kumar Kushwaha Sushri Soumya Jena Dr. Mihir Ranjan Sahoo Dr. Debashish Das Prof. Saroj Kumar Nayak 《Chemphyschem》2023,24(18):e202300032
High-voltage alkali metal-ion batteries (AMIBs) require a non-hazardous, low-cost, and highly stable electrolyte with a large operating potential and rapid ion conductivity. Here, we have reported a halogen-free high-voltage electrolyte based on SiB11(BO)12−. Because of the weak π-orbital interaction of −BO as well as the mixed covalent and ionic interaction between SiB11-cage and −BO ligand, SiB11(BO)12− has colossal stability. SiB11(BO)12− possesses extremely high vertical detachment energy (9.95 eV), anodic voltage limit (∼10.05 V), and electrochemical stability window (∼9.95 V). Furthermore, SiB11(BO)12− is thermodynamically stable at high temperatures, and its large size allows for faster cation movement. The alkali salts MSiB11(BO)12 (M=Li, Na, and K) are easily dissociated into ionic components. Electrolytes based on SiB11(BO)12− greatly outperform commercial electrolytes. In short, SiB11(BO)12−-based compound is demonstrated to be a high-voltage electrolyte for AMIBs. 相似文献
2.
Soumava Biswas Himanshu Sekhar Jena Suresh Sanda Prof. Dr. Sanjit Konar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(39):13793-13801
Three isostructural lanthanide‐based two‐ dimensional coordination polymers (CPs) {[Ln2(L)3(H2O)2]n ? 2n CH3OH) ? 2n H2O} (Ln=Gd3+ ( 1 ), Tb3+ ( 2 ), Dy3+ ( 3 ); H2L=cyclobutane‐1,1‐dicarboxylic acid) were synthesized by using a low molecular weight dicarboxylate ligand and characterized. Single‐crystal structure analysis showed that in complexes 1 – 3 lanthanide centers are connected by μ3‐bridging cyclobutanedicarboxylate ligands along the c axis to form a rod‐shaped infinite 1D coordination chain, which is further linked with nearby chains by μ4‐connected cyclobutanedicarboxylate ligands to form 2D CPs in the bc plane. Viewing the packing of the complexes down the b axis reveals that the lattice methanol molecules are located in the interlayer space between the adjacent 2D layers and form H‐bonds with lattice and coordinated water molecules to form 1D chains. Magnetic properties of complexes 1 – 3 were thoroughly investigated. Complex 1 exhibits dominant ferromagnetic interaction between two nearby gadolinium centers and also acts as a cryogenic magnetic refrigerant having a significant magnetic entropy change of ?ΔSm=32.8 J kg?1 K?1 for ΔH=7 T at 4 K (calculated from isothermal magnetization data). Complex 3 shows slow relaxation of magnetization below 10 K. Impedance analysis revealed that the complexes show humidity‐dependent proton conductivity (σ=1.5×10?5 S cm?1 for 1 , σ=2.07×10?4 S cm?1 for 2 , and σ=1.1×10?3 S cm?1 for 3 ) at elevated temperature (>75 °C). They retain the conductivity for up to 10 h at high temperature and high humidity. Furthermore, the proton conductivity results were correlated with the number of water molecules from the water‐vapor adsorption measurements. Water‐vapor adsorption studies showed hysteretic and two‐step water vapor adsorption (182000 μL g?1 for 1 , 184000 μL g?1 for 2 , and 1874000 μL g?1 for 3 ) in the experimental pressure range. Simulation of water‐vapor adsorption by the Monte Carlo method (for 1 ) confirmed the high density of adsorbed water molecules, preferentially in the interlayer space between the 2D layers. 相似文献
3.
Tuning CO2 Uptake and Reversible Iodine Adsorption in Two Isoreticular MOFs through Ligand Functionalization 下载免费PDF全文
Srinivasulu Parshamoni Suresh Sanda Dr. Himanshu Sekhar Jena Prof. Dr. Sanjit Konar 《化学:亚洲杂志》2015,10(3):653-660
The synthesis and characterization of two isoreticular metal–organic frameworks (MOFs), {[Cd(bdc)(4‐bpmh)]}n?2 n(H2O) ( 1 ) and {[Cd(2‐NH2bdc)(4‐bpmh)]}n?2 n(H2O) ( 2 ) [bdc=benzene dicarboxylic acid; 2‐NH2bdc=2‐amino benzene dicarboxylic acid; 4‐bpmh=N,N‐bis‐pyridin‐4‐ylmethylene‐hydrazine], are reported. Both compounds possess similar two‐fold interpenetrated 3D frameworks bridged by dicarboxylates and a 4‐bpmh linker. The 2D Cd‐dicarboxylate layers are extended along the a‐axis to form distorted square grids which are further pillared by 4‐bpmh linkers to result in a 3D pillared‐bilayer interpenetrated framework. Gas adsorption studies demonstrate that the amino‐functionalized MOF 2 shows high selectivity for CO2 (8.4 wt % 273 K and 7.0 wt % 298 K) over CH4, and the uptake amounts are almost double that of non‐functional MOF 1 . Iodine (I2) adsorption studies reveal that amino‐functionalized MOF 2 exhibits a faster I2 adsorption rate and controlled delivery of I2 over the non‐functionalized homolog 1 . 相似文献
4.
Biswajita Pradhan Srimanta Patra Chhandashree Behera Rabindra Nayak Bimal Prasad Jit Andrea Ragusa Mrutyunjay Jena 《Molecules (Basel, Switzerland)》2021,26(4)
Marine algae are a promising source of potent bioactive agents against oxidative stress, diabetes, and inflammation. However, the possible therapeutic effects of many algal metabolites have not been exploited yet. In this regard, we explored the therapeutic potential of Enteromorpha intestinalis extracts obtained from methanol, ethanol, and hexane, in contrasting oxidative stress. The total phenolic (TPC) and flavonoids (TFC) content were quantified in all extracts, with ethanol yielding the best values (about 60 and 625 mg of gallic acid and rutin equivalents per gram of extract, respectively). Their antioxidant potential was also assessed through DPPH•, hydroxyl radical, hydrogen peroxide, and superoxide anion scavenging assays, showing a concentration-dependent activity which was greater in the extracts from protic and more polar solvents. The α-amylase and α-glucosidase activities were estimated for checking the antidiabetic capacity, with IC50 values of about 3.8 µg/mL for the methanolic extract, almost as low as those obtained with acarbose (about 2.8 and 3.3 µg/mL, respectively). The same extract also showed remarkable anti-inflammatory effect, as determined by hemolysis, protein denaturation, proteinase and lipoxygenase activity assays, with respectable IC50 values (about 11, 4, 6, and 5 µg/mL, respectively), also in comparison to commercially used drugs, such as acetylsalicylic acid. 相似文献
5.
Jena Sudipta Ray Asit Sahoo Ambika Kamila Pradeep Kumar Nayak Sanghamitra Panda Pratap Chandra 《Chemistry of Natural Compounds》2021,57(6):1147-1149
Chemistry of Natural Compounds - 相似文献
6.
Superatoms are atomic clusters with tailored size and composition that mimic the chemistry of atoms in the periodic table. However, unlike the atoms whose chemistry is governed by their valence electron orbitals, the chemistry of superatoms is governed by their highest occupied molecular orbitals. In addition, due to their large size and non-spherical geometry, superatoms can promote unusual reactions and serve as the building blocks of cluster assembled materials with properties very different from conventional materials. This perspective highlights the unique role of superatoms in chemical and material sciences by focusing on superhalogens, which not only possess electron affinities larger than those of halogens but also can be stable when multiply charged. We discuss how these unique features of superhalogens enable noble gas atoms like argon to form chemical bonds at room temperature and zinc to exhibit an oxidation state of +3. The advantages of using superhalogens in the synthesis of water-resistant materials for solar cells, halogen-free electrolytes for solid-state batteries, and multiferroic materials are also discussed. 相似文献
7.
8.
Susil Kumar Jena 《Czechoslovak Mathematical Journal》2013,63(2):369-374
Each of the Diophantine equations A 4 ± nB 3 = C 2 has an infinite number of integral solutions (A,B,C) for any positive integer n. In this paper, we will show how the method of infinite ascent could be applied to generate these solutions. We will investigate the conditions when A, B and C are pair-wise co-prime. As a side result of this investigation, we will show a method of generating an infinite number of co-prime integral solutions (A,B,C) of the Diophantine equation aA 3 +cB 3 = C 2 for any co-prime integer pair (a, c). 相似文献
9.
Subhrakant Jena Kiran Devi Tulsiyan Dr. Rajiv K. Kar Dr. Hemanta K. Kisan Dr. Himansu S. Biswal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(13):4373-4383
Designing a potential protein–ligand pair is pivotal, not only to track the protein structure dynamics, but also to assist in an atomistic understanding of drug delivery. Herein, the potential of a small model thioamide probe being used to study albumin proteins is reported. By monitoring the Förster resonance energy transfer (FRET) dynamics with the help of fluorescence spectroscopic techniques, a twofold enhancement in the FRET efficiency of 2-thiopyridone (2TPY), relative to that of its amide analogue, is observed. Molecular dynamics simulations depict the relative position of the free energy minimum to be quite stable in the case of 2TPY through noncovalent interactions with sulfur, which help to enhance the FRET efficiency. Finally, its application is shown by pairing thiouracils with protein. It is found that the site-selective sulfur atom substitution approach and noncovalent interactions with sulfur can substantially enhance the FRET efficiency, which could be a potential avenue to explore in the design of FRET probes to study the structure and dynamics of biomolecules. 相似文献
10.
Solvent‐Dependent Structure of the I3− Ion Derived from Photoelectron Spectroscopy and Ab Initio Molecular Dynamics Simulations 下载免费PDF全文
Dr. Naresh K. Jena Ida Josefsson Dr. Susanna K. Eriksson Prof. Anders Hagfeldt Prof. Hans Siegbahn Prof. Olle Björneholm Prof. Håkan Rensmo Dr. Michael Odelius 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):4049-4055
Ab initio molecular dynamics (MD) simulations of the solvation of LiI3 in four different solvents (water, methanol, ethanol, and acetonitrile) are employed to investigate the molecular and electronic structure of the I3? ion in relation to X‐ray photoelectron spectroscopy (XPS). Simulations show that hydrogen‐bond rearrangement in the solvation shell is coupled to intramolecular bond‐length asymmetry in the I3? ion. By a combination of charge analysis and I 4 d core‐level XPS measurements, the mechanism of the solvent‐induced distortions has been studied, and it has been concluded that charge localization mediates intermolecular interactions and intramolecular distortion. The approach involving a synergistic combination of theory and experiment probes the solvent‐dependent structure of the I3? ion, and the geometric structure has been correlated with the electronic structure. 相似文献