This paper presents a study on a porous poly(methyl methacrylate) (PMMA)/polyvinylidene fluoride (PVDF) blend-based gel polymer electrolyte, activated in a liquid electrolyte of sodium ...tetrafluoroborate (NaBF
4
) in 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF
4
) ionic liquid. The optimized membrane shows porosity and liquid electrolyte uptake of 59% and 187%, respectively, and a maximum ionic conductivity of ~ 0.8 mS cm
−1
. The membrane shows a Na
+
ion transport number of 0.21 and an electrochemical stability window of ~ 5.5 V. A prototype battery using the optimized membrane delivers a discharge capacity of 130 mA h g
−1
at a drain current of 25 mA g
−1
.
Graphical Abstract
Ethanol is considered the most potential next generation automotive fuel because it is carbon‐neutral and could be produced from renewable resources like lignocellulosic biomass. There are some ...technological barriers such as pretreatment, saccharification of cellulose and hemicellulose matrix, and simultaneous fermentation of hexose and pentose sugars which needs to be addressed for efficient conversion of lignocellulosic biomass to bioethanol. This paper reviews the various process options and kinetic models adopted towards resolving the technological challenges to develop a low‐cost commercial process.
The current status of ethanol production using lignocellulosic raw materials is reviewed, describing the pretreatments required for enzymatic and acid saccharification of different types of biomass, fermentation by mesophiles and thermophiles, and improvement of the ethanol fermentation process for lignocellulosic bioethanol production.
The paper reports effect of dispersion of titanium dioxide (TiO
2
) nanofiller on the sodium ion conducting nanocomposite polymer electrolyte membranes consisting of TiO
2
dispersed membranes of ...poly(vinylidenedifluoride-co-hexafluoropropylene) (PVdF-HFP) soaked in a liquid electrolyte of sodium hexafluorophosphate (NaPF
6
) in ethylene carbonate (EC) and propylene carbonate (PC). The TiO
2
dispersed membranes have been prepared by phase inversion technique. The structural and morphological properties of the polymer electrolyte membranes have been investigated using x-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The membranes have been found to be highly porous with maximum porosity ~ 72% and liquid electrolyte uptake ~ 270%. Ionic conductivity of the electrolyte membranes containing different concentrations of TiO
2
has been measured by complex impedance spectroscopy. The maximum room temperature ionic conductivity has been found to be ~ 1.3 × 10
−3
S cm
−1
. The ionic conductivity measured with temperature has been found to follow VTF behavior. The ion transport numbers of the membranes have been studied using dc polarization, complex impedance, and cyclic voltammetry. The membranes have been found to be predominantly ionically conducting with Na
+
transport number ~ 0.31. The electrochemical stability window of the membranes has also been measured using cyclic voltammetry and found to be 3.5 V.
Glucose-regulated protein 78 (GRP78), is overexpressed in glioblastoma, other tumors and during viral and bacterial infections, and so, it is postulated to be a key drug target. EGCG, an ...ATP-competitive natural inhibitor, inhibits GRP78 effect in glioblastoma. Structural basis of its action on GRP78 nucleotide-binding domain and selectivity has been investigated. We were interested in exploring the large-scale conformational movements travelling to substrate-binding domain via linker region. Conformational effects of EGCG inhibitor as well as ATP on full length GRP78 protein were studied using powerful MD simulations. Binding of EGCG decreases mobility of residues in SBDα lid region as compared to ATP-bound state and similar to apo state. The decreased mobility may prevent its opening and closing over SBDβ. This hindrance to SBDα subdomain movement, in turn, may reduce the binding of substrate peptide to SBDβ. EGCG binding folds the protein stably as opposed to ATP binding. Several results from EGCG binding simulations are similar to that of the apo state. Key insights from these results reveal that after EGCG binding upon competitive inhibition with ATP, GRP78 conformation may revert to that of inactive, apo state. Further, SBD may adopt a semi-open conformation unable to facilitate association of substrates.
The performance of a Voltage Controlled Oscillator (VCO) is critical to meet the requirements of various wireless standards. This study highlights the use of a tunable active inductor (TAI) to build ...a VCO with a UMC 0.18 µm process. The exclusion of the MOS varactor and the use of minimal transistors in the design provide significant improvement in the overall silicon area. The proposed single-ended TAI with the feedback resistor achieves a good quality factor (Q) and wide inductive bandwidth. The proposed tunable active inductor involves a power dissipation of 310 µW at V
b
= 0.8 V. The use of two symmetrical active inductors in the design of VCO gives a tuning range from 754 MHz to 1.89 GHz. The obtained tuning range can meet the requirement of L-band applications & IEEE 802.11ah standards. The total power consumption range under 1.0 supply voltage (V
dd
) from 2.01 to 2.68 mW when the control voltage (V
b
) is increased from 0.2 to 2.0 V. The phase noise and figure of merit (FOM) obtained at 1 MHz relative frequency from the carrier were -89.64 dBc/Hz and -150.4, respectively. The total layout area consumed by VCO with and without pad-frame was 43.03 µm
39.04 µm and 22.11 µm
15.43 µm, respectively, which is very low as compared to spiral inductor based VCO. Corner analysis, Monte Carlo analysis, temperature sweep analysis, and Stability analysis were carried out to validate the reliability and robustness of the VCO.
Jatropha curcas has been widely planted without knowing its standard package of practice for optimizing the yield. Therefore, a standardized agro-technology of Jatropha is required. With this ...purpose, in this study an elite accession of Jatropha was planted at seven sites in India, covering a range of edapho-climatic conditions. Three experimental trials (spacing, pruning and irrigation and fertilizer) were carried out wherein its growth and yield performance were assessed for five years (2007–2012) at all the sites. The growth characters like plant height and number of branches showed significant variations among the sites and the effects of treatments were not uniform across the sites, indicating that site-specific package of practices should be followed instead of adopting the general recommendations. The seed yield was disappointing to recommend it randomly for large scale plantations on degraded lands in India. But results from the multi-location trials have shown good prospects at semi-arid (Bhavnagar) and drylands (Hyderabad); where plants in close spacing (2 × 2 m) produced significantly higher seed yield per unit area upto 1.4 t ha−1 (Bhavnagar) in comparison to wide spacing. Pruning showed a negative effect on seed yield during initial five years. We found that the following prescription was sufficient to optimize the yield on India's degraded soils: irrigation at a 30 day interval, and for each planting hole 2 kg of Farm Yard Manure (organic manure) and nitrogen, phosphorous and potassium at 10 g, 20 g, and 10 g, respectively.
► Field trial performance of Jatropha curcas L. (Jatropha) for five years. ► Spacing, pruning, irrigation and fertilizer treatments were standardized. ► Jatropha is yet not competitive with respect to seed and oil yield per unit area. ► Uniform agronomic package is not suitable for all the sites. ► Current findings conclude that Jatropha has no commercial potential so far in India.
A series of polyurethane (PU)-urea-imide coatings were synthesized by a systematic three-step reaction process. Initially isocyanate terminated PU prepolymers were prepared by reacting soft segments ...such as polyester polyols (prepared from neopentyl glycol, adipic acid, isophathalic acid and trimethylol propane) or polyether polyols (polypropylene glycol-1000) with hard segments such as 2,4-toluene diisocyanate or isophorone diisocyanate with NCO/OH ratio of 2:1. Heterocyclic imide ring into the PU backbone was incorporated by co-polymerization with pyromellitic dianhydride (PMDA) from the excess NCO groups in the PU prepolymer with an NCO/anhydride ratio of 1:0.5 and the surplus NCO content after imidization was moisture cured. PU-urea-imide coatings were also obtained by partial chain extension of the excess NCO groups in the NCO terminated PU-imide copolymers, and the remaining excess NCO groups were completely reacted with atmospheric moisture. The obtained polymers were analyzed with Fourier transform-infrared (FT-IR) and angle resolved X-ray photoelectron spectroscopy (AR-XPS). The type and change in intermolecular H-bonding interaction in the PU-urea-imide films with structural variables was identified by deconvolution of the FT-IR spectra using Origin 6.0 software through Gaussian curve-fitting method. The FT-IR analyses of the PU-urea-imide coating films show dependence of phase separation on the nature of chain extender. Surface characterization data from AR-XPS suggests the dependence of phase segregation behaviour on the nature of the chain extender, which also supports the FT-IR observations.
In order to investigate the mechanism of As release to anoxic ground water in alluvial aquifers, the authors sampled ground waters from 3 piezometer nests, 79 shallow (<45 m) wells, and 6 deep (>80 ...m) wells, in an area 750 m by 450 m, just north of Barasat, near Kolkata (Calcutta), in southern West Bengal. High concentrations of As (200–1180 μg
L
−1) are accompanied by high concentrations of Fe (3–13.7 mg
L
−1) and PO
4 (1–6.5 mg
L
−1). Ground water that is rich in Mn (1–5.3 mg
L
−1) contains <50 μg
L
−1 of As. The composition of shallow ground water varies at the 100-m scale laterally and the metre-scale vertically, with vertical gradients in As concentration reaching 200 μg
L
−1
m
−1. The As is supplied by reductive dissolution of FeOOH and release of the sorbed As to solution. The process is driven by natural organic matter in peaty strata both within the aquifer sands and in the overlying confining unit. In well waters, thermo-tolerant coliforms, a proxy for faecal contamination, are not present in high numbers (<10 cfu/100 ml in 85% of wells) showing that faecally-derived organic matter does not enter the aquifer, does not drive reduction of FeOOH, and so does not release As to ground water.
Arsenic concentrations are high (≫50 μg
L
−1) where reduction of FeOOH is complete and its entire load of sorbed As is released to solution, at which point the aquifer sediments become grey in colour as FeOOH vanishes. Where reduction is incomplete, the sediments are brown in colour and resorption of As to residual FeOOH keeps As concentrations below 10 μg
L
−1 in the presence of dissolved Fe. Sorbed As released by reduction of Mn oxides does not increase As in ground water because the As resorbs to FeOOH. High concentrations of As are common in alluvial aquifers of the Bengal Basin arise because Himalayan erosion supplies immature sediments, with low surface-loadings of FeOOH on mineral grains, to a depositional environment that is rich in organic mater so that complete reduction of FeOOH is common.
The rapid increase in electronic waste (e-waste) generation and its unsustainable management pose a threat to the environment and human well-being. However, various valuable metals are present in ...e-waste, which makes it a potential secondary source to recover metals. Therefore, in the present study, efforts were made to recover valuable metals (Cu, Zn, and Ni) from waste printed circuit boards (WPCB) of computers using methanesulfonic acid (MSA). MSA is contemplated as a biodegradable green solvent and has a high solubility for various metals. The effect of various process parameters (MSA concentration, H2O2 concentration, stirring speed, liquid to solid ratio, time, and temperature) was investigated on metal extraction to optimize the process. At the optimized process conditions, 100% extraction of Cu and Zn was achieved, while Ni extraction was around 90%. The kinetic study for metal extraction was performed using a shrinking core model and findings showed that MSA-aided metal extraction is a diffusion-controlled process. Activation energies were found to be 9.35, 10.89, and 18.86 kJ/mol for Cu, Zn, and Ni extraction, respectively. Furthermore, the individual recovery of Cu and Zn was achieved using the combination of cementation and electrowinning, which resulted in 99.9% purity of Cu and Zn. The current study proposes a sustainable solution for the selective recovery of Cu and Zn from WPCB.
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•Biodegradable green solvent (methanesulfonic acid) was used for metal recovery.•100% extraction of Cu and Zn was achieved while the extraction of Ni was 90%.•Combination of cementation and electrowinning was employed for metal recovery.•Individual recovery of Cu and Zn was achieved with 99.9% purity.•Metal extraction using MSA is a diffusion-controlled process.
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