A Ni(II) dinuclear complex bridged by end-on azide-N and phenolate-O atoms: spectral interpretation, magnetism and biological study

A new dinuclear complex, [Ni(L)(μ1,1-N3)Ni(L)(OH2)2]·ClO4(1), has been synthesized. It shows the presence of ferromagnetic interactions and is endowed with both anti-mycobacterial and anticancer properties

Zinc Porphyrins Possessing Three p-Carboxyphenyl Groups: Effect of the Donor Strength of Push-Groups on the Efficiency of Dye Sensitized Solar Cells

Zinc porphyrins decorated with three p-carboxyphenyl anchoring groups and various “push” substituents of varied electron-donating strengths were prepared in good yields by facile and straightforward ways. The effect of electron-donating strength of the donor molecules on the overall power conversion efficiency was evaluated with the help of photophysical, electrochemical, photovoltaic spectroscopy and quantum chemical calculations. It is observed from the photophysical and Infrared (IR) spectroscopic data that multi-anchoring dyes are more stable and bind more strongly to the TiO2 surface than their one-anchor counterparts. The properties like a three-step synthesis, high overall yields, possible mass production on a gram-scale and strong binding affinities with TiO2 surfaces make them a suitable choice for commercial applications. Zn1NH3A, with electron donating and anti-aggregation characteristics, achieved the highest efficiency of 6.50%

Effects of Number and Position of Meta and Para Carboxyphenyl Groups of Zinc Porphyrins in Dye-Sensitized Solar Cells: Structure–Performance Relationship

Porphyrin sensitizers containing <i>meta</i>- and <i>para</i>-carboxyphenyl groups in their meso positions have been synthesized and investigated for their performance in dye-sensitized solar cells (DSSCs). The superior performance of para-derivative compared to meta-derivative porphyrins was revealed by optical spectroscopy, electrochemical property measurements, density functional theory (DFT) calculations, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, incident photon-to-current conversion efficiency (IPCE), electrochemical impedance spectroscopy (EIS), and stability performance. Absorption spectra of <i>para</i>-carboxyphenyl-substituted porphyrins on TiO₂ show a broader Soret band compared to <i>meta</i>-carboxyphenyl-substituted porphyrins. ATR-FTIR spectra of the studied porphyrins on TiO₂ were applied to investigate the number and mode of carboxyl groups attached to TiO₂. The <i>V</i>_OC, <i>J</i>_SC, and IPCE values of para-series porphyrins were distinctly superior to those of meta-series porphyrins. The Nyquist plots of the studied porphyrins show that charge injection in para-series porphyrins is superior to that in meta-series porphyrins. The orthogonally positioned para derivatives have more efficient charge injection and charge transfer over charge recombination, whereas the efficiencies of flat-oriented meta derivatives are retarded by rapid charge recombination. Photovoltaic measurements of the studied <i>meta</i>- and <i>para</i>-carboxyphenyl-functionalized porphyrins show that the number and position of carboxyphenyl groups play a crucial role in the performance of the DSSC. Our results indicate that <i>para</i>-carboxyphenyl derivatives outperform <i>meta</i>-carboxyphenyl derivatives to give better device performance. This study will serve as a guideline for the design and development of organic, porphyrin, and ruthenium dyes in DSSCs

A new Ni(II) coordination polymer formed by bulky bis(imidazole) and 4,4â\u80²-oxybis(benzoic acid): Topological and spectral elucidation

A new coordination polymer, [Ni(dia)(oba)(H2O)]·H2On(1), was synthetized under hydrothermal conditions from the N-donor ancillary ligand, 9,10-di(1H-imidazol-1-yl)anthracene) (dia) and the flexible aromatic carboxylate, 4,4â\u80²-oxybis(benzoic acid) (oba) as organic linker. The two-dimensional framework of the polymer can be described as a 4-c uninodal net of topological type sql with point symbol 44.62. The structure well exhibits the rich coordination chemistry of dia and oba ligands as connectors; interestingly, two carboxylate groups of the oba ligand show μ1:η2and μ1:η1bridging coordination modes, connecting two Ni(II) ions possessing a six-connected NiN2O4 octahedral environment. EPR spectra for 1 were measured at different temperature and solvent. Variable temperature magnetic susceptibility confirms that a weak antiferromagnetic interaction among the Ni(II) ions exists. Thermal analysis has also been carried out to assess the thermal stability of 1 and its structural variation as a function of the temperature

Knowledge, Attitude, and Practices Regarding Fall Prevention Strategies among Spine and Hip Post-operative Elderly Individuals: A Cross-Sectional Study

Background: Falls and their consequences are always considered significant public health issue. Fall is considered a major health concern that makes older people more prone to injury and loss of life. Fractures of the hip, trunk, wrist, and neck are among the most common injuries caused by falls. Falls can cause disability, activity restriction, and fear of falling, all of which can affect quality of life and independence. As a result, inquiring about falls and assessing knowledge about falls, near falls, and fear of falling can assist us in identifying and mitigating any modifiable hazards before the next fall and also can help us shorten the rehabilitation period in the immediate post-operative period. Objectives: The objectives of the study were to determine the status of knowledge, attitude, and practices of falls prevention strategy among post-operative hip and spine elderly individuals in Karad. Materials and Methods: From July to December 2020, a cross-sectional investigation was conducted in a rural tertiary care hospital in Karad. In this study, a total of 100 individuals participated who had undergone spinal (n = 33) and hip (n = 67) surgeries. A consent form was filled out by the participants and completed a three-part questionnaire that asked questions about knowledge, attitude, and practices regarding fall prevention strategies. Following that, the data were examined using acceptable statistical procedures, and Excel was used to create various graphs with supplied frequencies and percentages generated using the software. The grade was determined by calculating the score into good/average/poor/very poor. Results: The present study shows that elderly people have poor awareness of how prone they are to falls postoperatively. At the same time, 17% of participants show very poor knowledge regarding fall prevention strategies. When assessed about the prevalence of attitudes and practices of the fall prevention program, 62% of participants exhibited a poor score. Conclusion: Based on the responses, there is a scarcity of knowledge regarding fall prevention strategies among the post-operative elderly individuals in Karad. The awareness regarding the knowledge and practice will thereby reduce the number of yearly falls both postoperatively and the silent falls. This practice would ensure a significant reduction in the post-fall complications and morbidity due to falls, thus leading to an improved quality of health care in the geriatric age group

Structural elucidation, EPR and magnetic interpretation of lanthanide (Ln = La, Nd, Sm) compounds with 4,4′-bipyridine and 2-sulfoterephthalate

A series of three lanthanide compounds, namely, [La(stp)(bipy)(H2O)]·H2On(1), [Nd(stp)(bipy)(H2O)]·2H2On(2), and [Sm(stp)(bipy)(H2O)]·H2On(3) has been synthesized through the reaction of 2-sulfoterephthalic acid monosodium salt Na(H2stp), trivalent lanthanide nitrate [Ln(NO3)3·6H2O] and N-donor ancillary co-ligand, 4,4′-bipyridine (bipy). As a result of the potential coordination modes of the stp ligand and the bipy co-ligand, the aforementioned compounds are arranged in a 2-D network, as evidenced by single-crystal X-ray diffraction technique. In all the three compounds, the Ln ion presents a distorted tricapped trigonal-prismatic coordination geometry. The EPR measurements evidence a diamagnetic behaviour of compound 1 (La3+) whereas there exhibits a weak antiferromagnetic coupling between paramagnetic Ln3+ions (Nd3+and Sm3+) for compounds 2 and 3. This is also supported by the magnetic data obtained for compounds 1–3. The encapsulation of the lanthanide coordination polymers displays a moderate luminescent property

Doubly end-on azido bridged mixed-valence cobalt trinuclear complex: spectral study, VTM, inhibitory effect and antimycobacterial activity on human carcinoma and tuberculosis cells

Doubly end-on azido-bridged mixed-valence trinuclear cobalt complex, [Co3(L)2(N3)6(CH3OH)2] (1) is afforded by employing a potential monoanionic tetradentate-N2O2 Schiff base precursor (2-[{[2-(dimethylamino)ethyl]imino}methyl]-6-methoxyphenol; HL). Single crystal X-ray structure reveals that in 1, the adjacent CoII and CoIII ions are linked by double end-on azido bridges and thus the full molecule is generated by the site symmetry of a crystallographic twofold rotation axis. Complex 1 is subjected on different spectral analysis such as IR, UV&#8212;vis, emission and EPR spectroscopy. On variable temperature magnetic study, we observe that during cooling, the χMT values decrease smoothly until 15 K and then reaches to the value 1.56 cm3 K mol−1 at 2 K. Complex 1 inhibits the cell growth on human lung carcinoma (A549 cells), human colorectal (COLO 205 and HT-29 cells), and human heptacellular (PLC5 cells) carcinoma cells. Complex 1 exhibits anti-mycobacterial activity and considerable efficacy on Mycobacterium tuberculosis H37Rv ATCC 27294 and H37Ra ATCC 25177 strains

Influence of Tin Doped TiO2 Nanorods on Dye Sensitized Solar Cells

The one-step hydrothermal method was used to synthesize Sn-doped TiO2 (Sn-TiO2) thin films, in which the variation in Sn content ranged from 0 to 7-wt % and, further, its influence on the performance of a dye-sensitized solar cell (DSSC) photoanode was studied. The deposited samples were analyzed by X-ray diffraction (XRD) and Raman spectroscopy, which confirmed the existence of the rutile phase of the synthesized samples with crystallite size ranges in between 20.1 to 22.3 nm. In addition, the bare and Sn-TiO2 thin films showed nanorod morphology. A reduction in the optical band gap from 2.78 to 2.62 eV was observed with increasing Sn content. The X-ray photoelectron spectroscopy (XPS) analysis confirmed Sn4+ was successfully replaced at the Ti4+ site. The 3-wt % Sn-TiO2 based DSSC showed the optimum efficiency of 4.01%, which was superior to 0.87% of bare and other doping concentrations of Sn-TiO2 based DSSCs. The present work reflects Sn-TiO2 as an advancing material with excellent capabilities, which can be used in photovoltaic energy conversion devices