Air transport describes an inevitable part in the day to day life of the modern world. It is highly responsible for the worldwide social contacts and business developments. The use of petroleum fuels ...as energy source for air transport is not sustainable. Aviation is one of the leading contributors to the total greenhouse gas emissions. Also, the fossil fuel prices are becoming more volatile day by day. So it is very essential to introduce and industrialize alternative aviation fuels generated from renewable resources, especially biomass. A number of industrial commitments and collaborations have emerged to find alternative ways to reach bio aviation fuels. Research on the conversion of biomass based sources to bio jet fuels is of current interest. The main concern is the production of biojet fuel, from renewable resources, with relatively low greenhouse gas life cycle and sustainability with affordable price. The present paper overviews the opportunities and challenges in the development of alternative fuels for aviation. The production process, feedstock used and the most promising global projects are also reviewed.
Cassava is the major source of calories for more than 250 million Sub-Saharan Africans, however, it has the lowest protein-to-energy ratio of any major staple food crop in the world. A cassava-based ...diet provides less than 30% of the minimum daily requirement for protein. Moreover, both leaves and roots contain potentially toxic levels of cyanogenic glucosides. The major cyanogen in cassava is linamarin which is stored in the vacuole. Upon tissue disruption linamarin is deglycosylated by the apolplastic enzyme, linamarase, producing acetone cyanohydrin. Acetone cyanohydrin can spontaneously decompose at pHs >5.0 or temperatures >35°C, or is enzymatically broken down by hydroxynitrile lyase (HNL) to produce acetone and free cyanide which is then volatilized. Unlike leaves, cassava roots have little HNL activity. The lack of HNL activity in roots is associated with the accumulation of potentially toxic levels of acetone cyanohydrin in poorly processed roots. We hypothesized that the over-expression of HNL in cassava roots under the control of a root-specific, patatin promoter would not only accelerate cyanogenesis during food processing, resulting in a safer food product, but lead to increased root protein levels since HNL is sequestered in the cell wall. Transgenic lines expressing a patatin-driven HNL gene construct exhibited a 2-20 fold increase in relative HNL mRNA levels in roots when compared with wild type resulting in a threefold increase in total root protein in 7 month old plants. After food processing, HNL overexpressing lines had substantially reduced acetone cyanohydrin and cyanide levels in roots relative to wild-type roots. Furthermore, steady state linamarin levels in intact tissues were reduced by 80% in transgenic cassava roots. These results suggest that enhanced linamarin metabolism contributed to the elevated root protein levels.
Ultraviolet (UV) photodetectors have drawn extensive attention due to their numerous applications in both civilian and military areas including flame detection, UV sterilization, aerospace UV ...monitoring, missile early warning, and ultraviolet imaging. Zinc oxide (ZnO)-based UV detectors exhibit remarkable performance; however, many of them are not visible-blind, and the fabrication techniques involve a high-temperature annealing step. Here, we fabricated a p-n junction photodiode based on annealing-free ZnO thin films prepared from ZnO nanoparticles and
N
,
N
′-di(1-naphthyl)-
N
,
N
′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB). NPB was chosen due to its transparent nature in the visible region and high hole mobility. The ZnO nanoparticles and thin films were characterized by UV-visible absorption spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), dynamic light scattering (DLS) particle size analysis, Fourier-transform infrared (FTIR) spectroscopy, photoluminescence spectroscopy, XRD and profilometry. The device exhibited responsivity of 0.037 A/W and an external quantum efficiency (EQE) of 12.86% at 5 V bias under 360 nm illumination. In addition, with no biasing, the device exhibited an on-off ratio of more than 10
3
and a linear dynamic range (LDR) of 63 dB. A high built-in potential at the ZnO/NPB interface could be the reason for this performance at zero bias. The rise and fall times were 156 ms and 319 ms, respectively. The results suggest that a visible-blind UV photodetector with acceptable performance can be fabricated using annealing-free ZnO films, which may lead to the realization of flexible detectors due to the low-temperature processes involved.
Visible-blind ultraviolet photodetectors have been fabricated with a p-n junction based on ZnO and an organic hole transport layer.
Cassava mosaic disease (CMD) suppresses cassava yields across the tropics. The dominant CMD2 locus confers resistance to cassava mosaic geminiviruses. It has been reported that CMD2-type landraces ...lose resistance after regeneration through de novo morphogenesis. As full genome bisulfite sequencing failed to uncover an epigenetic mechanism for this loss of resistance, whole genome sequencing and genetic variant analysis was performed and the CMD2 locus was fine-mapped to a 190 kilobase interval. Collectively, these data indicate that CMD2-type resistance is caused by a nonsynonymous, single nucleotide polymorphism in DNA polymerase δ subunit 1 (MePOLD1) located within this region. Virus-induced gene silencing of MePOLD1 in a CMD-susceptible cassava variety produced a recovery phenotype typical of CMD2-type resistance. Analysis of other CMD2-type cassava varieties identified additional candidate resistance alleles within MePOLD1. Genetic variation of MePOLD1, therefore, could represent an important genetic resource for resistance breeding and/or genome editing, and elucidating mechanisms of resistance to geminiviruses.
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A one pot synthesis of carbon dot incorporated porous coconut shell char derived sulphonated catalyst is reported here for the first time and is effectively used in the multicomponent ...synthesis of amidoalkyl naphthol. Macroporous nature of the char is revealed from scanning electron microscopic (SEM) analysis, whereas the dispersion of carbon dots (CDs) on the porous coconut shell char is confirmed from the high resolution transmission electron microscopic (HRTEM) analysis. Fluorescence emission spectrum further confirmed the presence of CDs in the catalyst. Fourier-transform infrared (FTIR) spectral analysis of the materials indicated that sulphonation occurred both to the CD and to the porous char. X-ray photo electron spectroscopic (XPS) analysis of the most active catalyst confirmed the presence of both sulphonic acid and carboxylic acid groups in the catalyst. The coconut shell char derived materials prepared by varying the amount of H2SO4 are successfully utilized as efficient alternative green catalysts for the multicomponent reaction, where excellent activity in amidoalkyl naphthol synthesis is obtained within short periods under solvent free reaction conditions. A maximum yield of 98% is obtained in the synthesis of N-Phenyl-(2-hydroxy-naphthalen-1-yl)-methyl-benzamide, the representative amidoalkyl naphthol, with the best catalyst within 3 min of reaction. The catalyst is highly active for the reactions carried out with varieties of aldehydes and amides with a product yield in the range of 88–98%. The best catalyst system retained more than 90% of its initial activity even upto 6th repeated run.
A heterostructured nanocomposite material consisting of MoS2 nanowires and RuO2 nanoparticles has been synthesized by an easy hydrothermal method and a simple chemical reduction technique followed by ...a calcination process. For the first time, the electrochemical performance of the as-prepared RuO2 nanoparticle dispersed MoS2 hybrid composite has been evaluated in three-electrode as well as symmetric two-electrode configurations in 1 M KOH electrolyte. At 1 Ag-1, the MoS2-RuO2 hybrid electrode exhibits specific capacitance (Csp) values of 972 Fg-1 (3- electrode) and 719 Fg-1 (two-electrode). Moreover, the symmetric supercapacitor based on the composite electrodes retains 100% cycling stability over 10000 cycles, which makes MoS2-RuO2 composite, a promising electrode for energy storage applications.
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•A symmetric supercapacitor based on MoS2-RuO2 nanocomposite has been fabricated for the first time.•The supercapacitor exhibited the specific capacitance value of 718.5 Fg-1 at 1 Ag-1 in symmetric configuration.•The supercapacitor retained 100% of its initial capacitance even after 10000 cycles of charge discharge.•At a constant power density 0.6 kWkg−1, the supercapacitor exhibited an energy density value of 35.92 Whkg−1.
There is a growing interest in decentralized wastewater management (DWWM) as a potential alternative to centralized wastewater management (CWWM) in developing countries. However, the comparative cost ...of CWWM and DWWM is not well understood. In this study, the cost of cluster-type DWWM is simulated and compared to the cost of CWWM in Alibag, India. A three-step model is built to simulate a broad range of potential DWWM configurations with varying number and layout of cluster subsystems. The considered DWWM scheme consists of cluster subsystems, that each uses simplified sewer and DEWATS (Decentralized Wastewater Treatment Systems). We consider CWWM that uses conventional sewer and an activated sludge plant. The results show that the cost of DWWM can vary significantly with the number and layout of the comprising cluster subsystems. The cost of DWWM increased nonlinearly with increasing number of comprising clusters, mainly due to the loss in the economies of scale for DEWATS. For configurations with the same number of comprising cluster subsystems, the cost of DWWM varied by ±5% around the mean, depending on the layout of the cluster subsystems. In comparison to CWWM, DWWM was of lower cost than CWWM when configured with fewer than 16 clusters in Alibag, with significantly less operation and maintenance requirement, but with higher capital and land requirement for construction. The study demonstrates that cluster-type DWWM using simplified sewer and DEWATS may be a cost-competitive alternative to CWWM, when carefully configured to lower the cost.
•Cost of centralized and decentralized wastewater management are in comparable range.•Decentralized wastewater management cost varies with layout and decentralization degree.•When strategically configured, decentralization reduces cost of wastewater management.
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•Novel EMI shielding aerogel made of V2O5 nanowires, is reported for the first time.•Method of preparation involved a facile polymerisation followed by freeze drying.•Ultra-low dense ...aerogels (0.02 g/cc), displayed high SSE of 1662.2 dB cm3 g−1.•Absorption-dominant V2O5-PANI aerogels show high green index of ~2.91.
Green electromagnetic interference (EMI) shielding materials are the most promising among EM wave attenuating solutions because of their less environmental hazard resulting from efficiently attenuating spurious waves with minimal secondary reflection. Against this background, the present paper reports a facile strategy for developing green and ultra-lightweight aerogels-based EM wave absorbers with low carbon content. Herein, we realized a peculiar 3D nanoarchitectured aerogel using nanowires of a layered oxide V2O5, which was further reinforced by a conducting polymer, polyaniline (PANI). The structure, morphology, formation of gel, and the EMI shielding properties of V2O5- PANI composite aerogel were investigated in detail. The mesoporous aerogel has a very low density of ~0.02 g/cc with maximum EMI shielding efficiency (EMI SE) of 34 dB in the X band, with an impressive specific shielding efficiency of 1662.2 dB cm3 g−1. Green index (gs) is found to be one of the highest so far (~2.91). The excellent show of EMI SE is ascribed to the multiple internal reflections inside the layered structure of V2O5 and intrinsic conducting properties of the polyaniline. Ours is the first-ever report of an eco-friendly, lightweight EMI shielding solution employing inorganic V2O5 nanowires forming robust EMI attenuating aerogel, which are free of carbonaceous fillers like carbon nanotube, graphene or even MXene.
New ways of directly using solar energy to charge electrochemical energy storage devices such as batteries would lead to exciting developments in energy technologies. Here, a two‐electrode photo ...rechargeable Li‐ion battery is demonstrated using nanorod of type II semiconductor heterostructures with in‐plane domains of crystalline MoS2 and amorphous MoOx. The staggered energy band alignment of MoS2 and MoOx limits the electron holes recombination and causes holes to be retained in the Li intercalated MoS2 electrode. The holes generated in the MoS2 pushes the intercalated Li‐ions and hence charge the battery. Low band gap, high efficiency photo‐conversion and efficient electron–hole separation help the battery to fully charge within a few hours using solar light. The proposed concept and materials can enable next generation stable photo‐rechargeable battery electrodes, in contrast to the reported materials.
The working (photo charging) of single nanorod (NR) containing a MoS2/MoOx heterostructure based two‐electrode photo rechargeable battery. A high‐resolution high angle annual dark‐field image of the NR is also shown indicating the structure containing both amorphous (MoOx) and crystalline (MoS2) regions.
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