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Light‐induced degradation (LID) is a well‐known problem faced by p‐type Czochralski (Cz) monocrystalline silicon (mono‐Si) wafer solar cells. In mono‐Si material, the physical mechanism has been traced to the formation of recombination active boron‐oxygen (B–O) complexes, which can be permanently deactivated through a regeneration process. In recent years, LID has also been identified to be a significant problem for multicrystalline silicon (multi‐Si) wafer solar cells, but the exact physical mechanism is still unknown. In this work, we study the effect of LID in two different solar cell structures, aluminium back‐surface‐field (Al‐BSF) and aluminium local back‐surface‐field (Al‐LBSF or PERC (passivated emitter and rear cell)) multi‐Si solar cells. The large‐area (156 mm × 156 mm) multi‐Si solar cells are light soaked under constant 1‐sun illumination at elevated temperatures of 90 °C. Our study shows that, in general, PERC multi‐Si solar cells degrade faster and to a greater extent than Al‐BSF multi‐Si solar cells. The total degradation and regeneration can occur within ∼320 hours for PERC cells and within ∼200 hours for Al‐BSF cells, which is much faster than the timescales previously reported for PERC cells. An important finding of this work is that Al‐BSF solar cells can also achieve almost complete regeneration, which has not been reported before. The maximum degradation in Al‐BSF cells is shown to reduce from 2% (relative) to an average of 1.5% (relative) with heavier phosphorus diffusion.

Visible-light-assisted photodegradation of an azo dye, Reactive Red 180 (RR180), in the presence of nitrogen-doped TiO 2 (N-TiO 2 ) has been studied. The photodegradation of RR180 is evaluated through decolorization studies and total organic carbon analysis. The efficacy of hydrogen peroxide (H 2 O 2 ), potassium peroxomonosulfate (oxone or PMS), and potassium peroxodisulfate (PDS) in improving the photodegradation of the dye in the N-TiO 2 -RR180 system is also examined. The effect of combining photo-Fentonlike reaction with N-TiO 2 -mediated photodegradation of RR180 under visible light has been investigated. The photoactivity of N-TiO 2 -RR180-Fe 3+ /Cu 2+ -oxidant systems is compared with the individual techniques of photocatalysis and photo-Fenton-like reactions. The coupled system possesses superior photomineralization ability towards the abatement of RR180.

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Aims:The aim of this study was to observe the sequelae of fenugreek adjunctive to nonsurgical periodontal therapy and its comparison to a group treated with scaling and root planing (SRP) and metformin alone by assessing their respective effects on periodontal parameters, glycemic status, and serum lipid levels.Materials and Methods:The study comprised eighty patients who were further divided into two groups. Each group consisted of 40 patients. Group 1 consisted of uncontrolled noninsulin-dependent diabetes mellitus (NIDDM) patients with chronic generalized periodontitis, who received SRP and treatment with metformin. Group 2 consisted of uncontrolled NIDDM with chronic generalized periodontitis, who received SRP and metformin plus fenugreek powder. Periodontal parameters such as gingival index, plaque index, bleeding on probing, pocket depth, and clinical attachment levels were evaluated before treatment and 1 month after nonsurgical periodontal therapy. The values of low-density lipoprotein (LDL), triglycerides, total cholesterol (TC), and glycosylated hemoglobin (HbA1c) were assessed by collecting the blood samples before treatment and 1 month after treatment.Results:There was a statistically significant change in all the parameters seen clinically in both the groups. The glycemic status also showed a statistically significant reduction for fasting blood sugar (P < 0.001) on intragroup comparison. Intragroup comparison shows a statistically significant reduction (P < 0.001) for serum lipids, whereas intergroup comparison showed a statistically significant reduction after treatment only in TC and LDL levels (P < 0.02 and <0.012).Conclusion:This study shows that fenugreek powder can be used adjunctive to SRP to control the glycemic status and serum lipid levels in uncontrolled NIDDM patients.

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The synthesis of ZnO nanorods (ZnONRs), by virtue of their anisotropic electronic properties, and their exploitation as photoanode material for low-cost metal-free organic dye-sensitized solar cell (DSSC) are reported. The ZnO nanostructures were prepared through sol-gel method and characterized by scanning electron microscopy (SEM), UV-vis spectroscopy, photoluminescence (PL) spectroscopy and X-ray diffraction (XRD) analyses. The photovoltaic performance of the eosin yellow (eosin-Y) sensitized solar cell employing TiO 2 nanoparticles (TiO 2 NPs) modified poly(ethylene oxide) (PEO) based solid-state polymer electrolyte was evaluated under simulated standard global AM 1.5G sunlight (100 mW/cm 2 . The solar to electrical energy conversion efficiency ( ) of the ZnONRs based DSSC was 0.89%, which is 2.5 times higher than that of the DSSC fabricated with ZnO nanoparticles (0.35%). This enhancement in the efficiency is attributed to an effective conduction of electrons through the 1D ZnO nanostructures.

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