Facile synthesis of a three-dimensional Ln-MOF@FCNT composite for the fabrication of a symmetric supercapacitor device with ultra-high energy density: overcoming the energy storage barrier.

In order to quench the thirst for efficient energy storage devices, a novel praseodymium-based state-of-the-art three-dimensional metal-organic framework (MOF), {[Pr(pdc)2]Me2NH2}n (YK-1), has been synthesized by using a simple solvothermal method employing a readily available ligand. YK-1 was characterised by single-crystal XRD and crystallographic analysis. The electrochemical measurements of YK-1 show that it exhibits a specific capacitance of 363.5 F g-1 at a current density of 1.5 A g-1 with 83.8% retention after 5000 cycles. In order to enhance its electrochemical performance for practical application, two composites of YK-1 with graphene oxide (GO) and functionalised multi-walled carbon nanotubes (FCNTs), namely YK-1@GO and YK-1@FCNT, were fabricated by employing a facile ultrasonication technique. The as-synthesized MOF and the composites were characterized by PXRD, FTIR, SEM, and TEM techniques. YK-1@GO and YK-1@FCNT offer enhanced specific capacitances of 488.2 F g-1 and 730.2 F g-1 at the same current density with 93.8% and 97.7% capacity retention after 5000 cycles, respectively (at 16 A g-1). Fascinated by the outstanding results shown by YK-1@FCNT, a symmetric supercapacitor device (SSC) based on it was fabricated. The assembled SSC achieved a remarkable energy density (87.6 W h kg-1) and power density (750.2 W kg-1) at a current density of 1 A g-1, along with very good cycling stability of 91.4% even after 5000 GCD cycles. The SSC device was able to power up several LED lights and even operated a DC brushless fan for a significant amount of time. To the best of our knowledge, the assembled SSC device exhibits the highest energy density among the MOF composite-based SSCs reported so far.

A Case Report of Postcoital Dysphoria: A Paradoxical Melancholy.

Sexual engagement usually leads to positive and satisfactory feelings under typical circumstances. However, studies conducted in recent years have revealed that some people experience feelings of depression, anxiety, agitation, or aggression following sexual activity or masturbation. This condition, known as postcoital dysphoria (PCD), is a rare psychiatric disorder that has been reported more in women than in men. We present a rare case of a 24-year-old male who suffers from PCD. This provides clinical insight for studies further attempting to investigate PCD among males.

Thermoelectric transport properties of XAgP (X = Sr and Ba) from first principles.

For thermoelectric applications those materials are of interest that have significant power factor (PF) and low lattice thermal conductivity,κL. Here we theoretically exploreκLof two novel materials SrAgP and BaAgP using linearized Boltzmann transport equation with a single-mode relaxation time approach. We estimate the figure of meritzTby employingab-initiocalculations based on density functional theory and semiclassical Boltzmann transport theory. It is observed that at room temperature SrAgP exhibits slightly higher lattice thermal conductivity than BaAgP, which is mainly due to the large phonon group velocity. The relaxation time derived from deformation potential theory indicates a higherp-type PF for SrAgP compared to BaAgP over the entire temperature range. This provides an estimate for the figure of merit for the two materials. The low lattice thermal conductivity and higher PF make SrAgP a more promising thermoelectric material.

Structure, DFT studies and evaluation of catechol oxidase (CO) mimic activity of mononuclear Co(II) complexes derived from aminoalcohols: an experimental and theoretical approach.

The impetus to modeling of enzyme mimics comes from their potential to provide insight to the alternate mechanistic pathways of the native enzymes. The present study demonstrates the syntheses and characterization of two different cobalt(II) complexes, [Co(pdm)(Phen)Cl]Cl·H2O (1) and [Co(pmmH)2(SCN)2] (2) with the aminoalcohol ligands such as pyridine-2,6-dimethanol (pdmH2) or 2-pyridinemonomethanol (pmmH) and their assessment as catechol oxidase (CO) enzyme mimic. Single Crystal X-ray diffraction and powder X-ray diffraction data suggest the octahedral environment around the Co(II) ion and the complexes form extensive 1D or 2D propagating network as a result of non-covalent interactions (O···H and C-H···π). TD-DFT calculations were used to explain the spectral bands obtained during the UV-Vis absorption studies and it is ascertained that the transitions were mainly of the intra-ligand charge transfer (ILCT) type. The catecholase biomimetic catalytic activity of the synthesized complexes has been investigated in detail and the kinetics is also performed. The results obtained show that both the complexes catalyze the aerobic oxidation of catechol to the corresponding o-quinone. The Kcat value for 1 is 106.99 h‒1 and for 2 is 90.32 h‒1 in methanol. It may be mentioned here that 1 and 2 are effective catalysts, with the order of activity being 1 > 2. The order of enzymatic activity is well justified by CV and DFT studies.Communicated by Ramaswamy H. Sarma.

State of the art developments and prospects of metal-organic frameworks for energy applications.

The progress on technologies for the cleaner and ecological transformation and storage of energy to combat effluence or pollution and the impending energy dilemma has recently attracted interest from energy research groups, particularly in the field of coordination chemistry, among inorganic chemists. Carriers for storing energy or facilitating mass and e- transport are considered significant for energy conversion. Accordingly, considering their properties such as large surface area, low cost, customizable pore diameter, tunable topologies, low densities, and variable frameworks, MOFs (metal-organic frameworks) and their derivatives are well-suited for this purpose. MOFs are an innovative category of porous and crystalline materials, which have gained significant interest in recent years. Thus, herein, we highlight the state of the art progress on MOFs for energy-based applications, as perfect compounds and elements in compound assemblies for converting solar energy, lithium-ion arrays, fuel devices, hydrogen production, photocatalytic CO2 reduction, proton conduction, etc. In addition, the substantial progress achieved in the production of various composites and derivatives containing MOFs with particular focus on supercapacitors and gas adsorption and storage is summarized, concentrating on the correlation between their coordination structural frameworks and applications in the field of energy. The current improved strategies, challenges, and future prospects are also presented in view of the coordination chemistry governing the structural modification of MOFs for energy applications.

Soil heterotrophic respiration in response to rising temperature and moisture along an altitudinal gradient in a subtropical forest ecosystem, Southwest China.

Globally, one-third of the terrestrial carbon (C) is stored in tropical soils. The warming predicted for this century is expected to increase microbial decomposition in soil and escalate climate change potential by releasing more carbon dioxide (CO2) into the atmosphere. Understanding the response of soils to warming is a key challenge in predicting future climate change trajectories. Here we examined the combined effect of soil temperature (Ts) and soil water content (VWC) on soil heterotrophic respiration (Rsh) and its temperature sensitivity across different altitudes (2400, 1900, and 1450 m ASL) in the Ailaoshan subtropical forest ecosystem, Southwest China. Along the elevation gradient, soil C stocks in the top 10 cm soil layer increased significantly from 10.7 g/ kg at 1480 m ASL to 283.1 g/ kg at 2480 m ASL. Soil cores from various elevations were translocated to the same, and lower elevations and Rsh from those cores were measured every month from February 2010 to January 2014. Temperature sensitivity (Q10) of Rsh for the period was highest at the highest (H) elevation (Q10 = 5.3), decreased significantly towards the middle (M, Q10 = 3.1) and low (L, Q10 = 1.2) elevation. Q10 at M and L elevation did not differ between the place of origin and translocated cores. For the cores within each elevation, Q10 did not vary across the years. Our models suggest that Rsh increased significantly in response to an increase in Ts at each elevation under an intermediate VWC. Hence, the rate of emission was higher in lower elevations due to a higher Ts range. Our findings highlight that the predicted warming over the 21st century will have the greatest impact of Ts on Rsh, especially on the soils at the highest elevations, and will lead towards positive feedback to the climate system.

Fabrication of a lead ion selective membrane based on a polycarbazole Sn(iv) arsenotungstate nanocomposite and its ion exchange membrane (IEM) kinetic studies.

A polycarbazole-Sn(iv) arsenotungstate (Pcz-SnAT) nanocomposite cation exchanger membrane (CEM) was prepared via the casting solution technique utilizing polycarbazole-Sn(iv) arsenotungstate and PVC (polyvinyl chloride) as a binder. The synthesis of the Pcz-SnAT membrane was confirmed via various characterization methods such as EDX, SEM, TGA, XRD, and FTIR spectroscopy. This membrane having a 4.5 : 1 composition ratio of composite by PVC exhibited the most effective outcomes for swelling, thickness, porosity, and water content. Our research indicates that the present ion selective membrane electrode is selective towards Pb(ii) ions, with the detection limit ranging from 1 × 10-7 mol L-1 to 1 × 10-1 mol L-1 where 20 s is the response time and 3-7 is the working value pH. The mechanism of the Pcz SnAT ion exchange membrane was obtained by kinetic studies by utilizing the equation given by Nernst Planck at 40-80 °C. As a result, activation energy and thermodynamic studies were done. The analytical utility of this electrode is conventional by utilizing it as an electrode indicator within the potentiometric titration.

First-principles investigations of orthorhombic-cubic phase transition and its effect on thermoelectric properties in cobalt-based ternary alloys.

We screened six cobalt-based 18-VEC systems CoVSi, CoNbSi, CoTaSi (Si-group) and CoVGe, CoNbGe, CoTaGe (Ge-group) by the first-principles approach, with the motivation of stabilizing these orthorhombic phases into the cubic symmetry-favorable for thermoelectrics. Remarkably, it was found that the Ge-group is energetically more favorable in the cubic symmetry than the hitherto orthorhombic phase. We account the cubic ground state of the Si-group to the interplay of internal pressure and covalent interactions. The principle of reducing covalent interactions will provide insight and could be vital in speeding the search of missing cubic half-Heusler alloys. Meanwhile, the calculated transport properties of all the systems on p -type doping, except CoVSi, are more promising than the well-known CoTiSb. We also provide conservative estimates of the figure of merit, exceeding the CoTiSb. Based on our findings, we suggest possible new phases of ternary compounds for thermoelectric applications.

First-principles study of thermoelectric properties of Li-based Nowotony-Juza phases.

We investigated the cubic-hexagonal phase transition and its effect on thermoelectric performance in Li-based Nowotny-Juza phases LiZn X (X = N, P, As, Sb, and Bi). Interestingly, other than LiZnSb, the cubic LiZnBi is found to be energetically more favorable than the hitherto reported hexagonal phase. The hexagonal phases of reported cubic LiZnP and LiZnAs are likely to be stabilized by pressure-hydrostatic pressure can be aided by internal pressure. We find that while power factor values are much improved in the proposed hexagonal phases, the values in cubic phases are also impressive. We also determine conservative estimates of the figure of merit. The ZT values of cubic and hexagonal LiZnSb at 700 K are 1.27 and 1.95, respectively. Other promising values are 1.96 and 1.49 at 700 K of hexagonal n-type LiZnP and LiZnAs, respectively. Overall, our findings suggest the good thermoelectric potential of Nowotny-Juza phases.

Hydro-chemical characterization and quality assessment of a Western Himalayan river, Munawar Tawi, flowing through Rajouri district, Jammu and Kashmir, India.

Studies on river water quality in the Indian Himalayas are limited to a few larger ones; the smaller ones, although vital for a large section of people, mostly remain untouched. Therefore, Munawar Tawi a tributary of Chenab flowing through Rajouri district of Jammu region, Western Himalayas was selected for the study. Fifty-four water samples from 27 sites from Rajouri town and its upstream and downstream locations were collected during January and June 2014. Fourteen water quality parameters that include major cations and anions were analyzed. Water quality indicators such as SAR, %Na, RSC, MAR, KI, and PI were also calculated to determine suitability of water for irrigation. Piper plots identified four water types, of which Ca(2+)-Mg(2+)-HCO(-) 3 was the dominant type in both the seasons. While in January, water samples varied across all the four types, in June only two types were seen (i.e. Ca(2+)-Mg(2+)-HCO(-) 3 and Ca(2+)-Mg(2+)-Na(+)-HCO(-) 3). Ludwig-Langelier plot also showed Ca(2+)-Mg(2+)-HCO(-) 3 type as the dominant water type. Wilcoxon signed-rank test showed most of the parameters, except TDS, significantly high in January than in June. Kruskal-Wallis test showed significant variation in concentration among most of the parameters from upstream to the town and towards downstream. The water, with respect to the set standards (WHO, ISI, UNESCO), in both January and June, is found suitable for drinking and irrigation.

Potential Use of Rice Field Cyanobacterium Nostoc muscorum in the Evaluation of Butachlor Induced Toxicity and their Degradation.

In the present study, butachlor (5, 10, 20, 40 and 80 ppm) induced toxicity in Nostoc muscorum and their degradation was evaluated. The dose of butachlor dependent decreased in the cell survival and growth of N. muscorum was noticed. Scanning electron microscopy revealed the adverse impact on the cell size and shapes. Low concentrations of butachlor (10 and 20 ppm) induced the over expression of a polypeptides of 31.0 K Da and 42.7 K Da, respectively which could be responsible for developing resistance in the organism up to certain level. Further, the degradation product of butachlor as a result of metabolic activities of N. muscorum, identified by GC-MS analysis includes phenols and benzene dicarboxylic acid indicating the utilization of herbicide during active growth.

An enzoinformatics study targeting polo-like kinases-1 enzyme: Comparative assessment of anticancer potential of compounds isolated from leaves of Ageratum houstonianum.

Natural products from plant sources, embracing inherently ample structural diversity than synthetic ones are the major sources of anticancer agents and will constantly play as protagonists for discovering new drugs. Polo-like kinases (PLKs) play a leading role in the ordered execution of mitotic events and 4 mammalian PLK family members have been identified. PLK1 is an attractive target for anticancer drugs in mammalian cells, among the four members of PLKs. The present study expresses the molecular interaction of compounds (1,2-Benzenedicarboxylic acid bis (2 ethylhexyl) ester, squalene, 3,5-bis (1,1-dimethylethyl) phenol, Pentamethyl tetrahydro-5H-chromene, (1,4-Cyclohexylphenyl) ethanone and 6-Vinyl-7-methoxy-2,2-dimethylchromene) isolated from methanolic extract of leaves of Ageratum houstonianum with PLK1 enzyme. Docking between PLK1 and each of these compounds (separately) was performed using "Auto dock 4.2." (1,4-Cyclohexylphenyl) ethanone showed the maximum potential as a promising inhibitor of PLK1 enzyme with reference to ∆G (-6.84 kcal/mol) and Ki (9.77 µM) values. This was sequentially followed by Pentamethyl tetrahydro-5H-chromene (∆G = -6.60 kcal/mol; Ki = 14.58 µM), squalene (∆G = -6.17 kcal/mol; Ki = 30.12 µM), 6-Vinyl-7-methoxy-2,2-dimethylchromene (∆G = -5.91 kcal/mol; Ki = 46.68 µM), 3, 5-bis (1,1-dimethylethyl) phenol (∆G = -5.70 kcal/mol; Ki = 66.68 µM) and 1,2-Benzenedicarboxylic acid bis (2 ethylhexyl) ester (∆G = -5.58 kcal/mol; Ki = 80.80 µM). These results suggest that (1,4-Cyclohexylphenyl) ethanone might be a potent PLK1 inhibitor. Further, in vitro and in vivo rumination are warranted to validate the anticancer potential of (1,4-Cyclohexylphenyl) ethanone.

Growth, photosynthesis, active oxygen species and antioxidants responses of paddy field cyanobacterium Plectonema boryanum to endosulfan stress.

The present paper deals with the insecticide endosulfan (5, 10 and 20 microg/ml)-induced changes in physiological and biochemical parameters related to photosynthesis and defense systems in paddy field cyanobacterium Plectonema boryanum grown under laboratory conditions. Growth and photosynthetic pigments, i.e., chlorophyll a, carotenoids and phycocyanin, were adversely affected by endosulfan treatment and the inhibition was found to be dose dependent. The toxic effect of endosulfan was more pronounced on phycocyanin; however, a considerable reduction in chlorophyll a and carotenoids was also noticed. 14C-fixation appeared to be more sensitive to insecticide than whole cell oxygen evolution. Spheroplasts treated with endosulfan exhibited a severe effect on PSII activity which was mainly due to blocking of the electron flow at the water oxidation side. In contrast to this, similar doses of endosulfan caused the least effect on PSI activity (DCPIP/ASC-->MV). Furthermore, endosulfan with increasing doses accelerated the formation of active oxygen species, i.e., O2- and H2O2, in cells progressively, whereby an enhanced peroxidation of lipid and leakage of cell membrane were noticed. As a consequence of active oxygen species (AOS) generation in endosulfan-treated cells, the activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) was enhanced considerably. Besides the accelerated action of enzymatic defense systems, chemical antioxidant ascorbate showed a decreasing trend with the rising concentration of endosulfan (5, 10 and 20 microg/ml).