Multilayer assemblies of uniform ultrathin film electrodes with good electrical conductivity and very large surface areas were prepared for use as electrochemical capacitors. A layer-by-layer self-assembly approach was employed in an effort to improve the processability of highly conducting polyaniline (PANi) and chemically modified graphene. The electrochemical properties of the multilayer film (MF-) electrodes, including the sheet resistance, volumetric capacitance, and charge/discharge ratio, were determined by the morphological modification and the method used to reduce the graphene oxide (GO) to reduced graphene oxide (RGO) in the multilayer films. The PANi and GO concentrations could be modulated to control the morphology of the GO monolayer film in the multilayer assemblies. Optical ellipsometry was used to determine the thickness of the GO film in a single layer (1.32 nm), which agreed well with the literature value (~1.3 nm). Hydroiodic acid (HI), hydrazine, or pyrolysis were tested for the reduction of GO to RGO. HI was found to be the most efficient technique for reducing the GO to RGO in the multilayer assemblies while minimizing damage to the virgin state of the acid-doped PANi. Ultimately, the MF-electrode, which could be optimized by fine-tuning the nanostructure and selecting a suitable reduction method, exhibited an excellent volumetric capacitance, good cycling stability, and a rapid charge/discharge rate, which are required for supercapacitors. A MF-electrode composed of 15 PANi/RGO bilayers yielded a volumetric capacitance of 584 F/cm(3) at a current density of 3.0 A/cm(3). Although this value decreased exponentially as the current density increased, approaching a value of 170 F/cm(3) at 100 A/cm(3), this volumetric capacitance is one of the best yet reported for the other carbon-based materials. The intriguing features of the MF-electrodes composed of PANi/RGO multilayer films offer a new microdimensional design for high energy storage devices for use in small portable electronic devices.

Interactions of DNA with free base porphyrin, tetrakis(1-methylpyridium-4-yl)porphyrin (H 2 TMPyP 4+ ) and its metallo-derivative of ruthenium(II) have been investigated by UV-Vis, fluorescence and circular dichroism (CD) spectroscopy at 0.1 M NaCl, 7.5 pH and 25 °C. The results suggest that Ru(II)TMPyP 4+ interacts with DNA via outside binding in self-stacking manner as indicated by UV-Vis data, a small red shift (∆λ = 3 nm) and a minimal hypochromicity (10%) upon addition of DNA. CD spectra showed the presence of a new peak in the Soret region on addition of Ru(II)TMPyP 4+ to DNA solution. On the other hand, the interaction of free base porphyrin, H 2 TMPyP 4+with DNA revealed a significant hypochromicity (30%) and a large red shift (∆λ = 20 nm) in the UV-Vis results which conforms intercalation of free base porphyrin with DNA. In this case, the CD results showed only a negative peak developed in the Soret region during titration with DNA. Fluorescence spectroscopy revealed that initially aggregated porphyrin species were de-aggregated after addition of DNA. This phenomenon has been verified with the fluorescence experiments for the porphyrins in the presence of different concentrations of NaCl and ethanol. Ru(II)TMPyP 4+ showed enhanced DNA cleavage in the presence of EcoR1 restriction enzyme, where the enzyme did not cleave DNA. Metallo-porphyrins having the ability to cleave DNA could be used as chemotherapeutic agents for the treatment of African sleeping sickness (Trypanosomiasis).

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Although the power conversion efficiency (PCE) of inorganic perovskite‐based solar cells (PSCs) is considerably less than that of organic‐inorganic hybrid PSCs due to their wider bandgap, inorganic perovskites are great candidates for the front cell in tandem devices. Herein, the low‐temperature solution‐processed two‐terminal hybrid tandem solar cell devices based on spectrally matched inorganic perovskite and organic bulk heterojunction (BHJ) are demonstrated. By matching optical properties of front and back cells using CsPbI2Br and PTB7‐Th:IEICO‐4F BHJ as the active materials, a remarkably enhanced stabilized PCE (18.04%) in the hybrid tandem device as compared to that of the single‐junction device (9.20% for CsPbI2Br and 10.45% for PTB7‐Th:IEICO‐4F) is achieved. Notably, the PCE of the hybrid tandem device is thus far the highest PCE among the reported tandem devices based on perovskite and organic material. Moreover, the long‐term stability of inorganic perovskite devices under humid conditions is improved in the hybrid tandem device due to the hydrophobicity of the PTB7‐Th:IEICO‐4F back cell. In addition, the potential promise of this type of hybrid tandem device is calculated, where a PCE of as much as ≈28% is possible by improving the external quantum efficiency and reducing energy loss in the sub‐cells.

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The experiment was conducted to investigate the present status and potentialities of organic sheep production in Lakshmipur district of Bangladesh. Data were collected through an interview schedule personally from 30 respondents in 3 villages of Ramgoti Upazila who were involved in sheep production. Parameter studied were origin, feeds and fodder, breeding, health care, living condition of livestock and factors related to organic sheep production. All sheep was indigenous. 60 per cent farmers used roadside grass and 40% cultivated and roadside grass. Most of the farmers used mixed feed which was bought from local market and 17% farmers used vitamin mineral supplementation. All farmers used natural breeding. About 80, 80 and 83% farmers practiced vaccination, de-worming and grooming, respectively. About 13% farmers used hormone, antibiotic and growth promoter and only 33% farmers remove sick or injured animal from healthy stock. All farmers allowed access to outdoor and pasturing during winter season and none reared male and female sheep separately. Farmers did not keep and kept their livestock record were 90 and 10%, respectively. Most of the farmers were middle aged categories (53%) and education level of farmers of primary, secondary and higher secondary were 63, 30 and 7%, respectively.J. Environ. Sci. & Natural Resources, 10(2): 95-103 2017

As a byproduct of oil production, black and yellow mustard cakes protein are considered as potential source of plant protein for feed applications to poultry, fish and swine industries. The protein contents in black and yellow mustard cakes were 38.17% and 28.80% and their pepsin digestibility was 80.33% and 77.43%, respectively. The proteins were extracted at different pH and maximum proteins (89.13% of 38.17% and 87.76% of 28.80% respectively) isolated from black and yellow mustard cakes at pH 12. The purity of isolated proteins of black and yellow mustard cakes was 89.83% and 91.12% respectively and their pepsin digestibility was 89.67% and 90.17% respectively which assigned the absence of antinutritional compounds. It was found that essential amino acids isoleucine, lysine, methionine, threonine and tryptophan and non essential amino acids arginine and tyrosine were present in greater concentration in black mustard cake protein whereas other amino acids were higher in yellow mustard cake protein.

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