Experimental and Modeling Studies of the Combustion Characteristics of Conventional and Alternative Jet Fuels. Final Report

The objectives of this project have been to develop a comprehensive set of fundamental data regarding the combustion behavior of jet fuels and appropriately associated model fuels. Based on the fundamental study results, an auxiliary objective was to identify differentiating characteristics of molecular fuel components that can be used to explain different fuel behavior and that may ultimately be used in the planning and design of optimal fuel-production processes. The fuels studied in this project were Fischer-Tropsch (F-T) fuels and biomass-derived jet fuels that meet certain specifications of currently used jet propulsion applications. Prior to this project, there were no systematic experimental flame data available for such fuels. One of the key goals has been to generate such data, and to use this data in developing and verifying effective kinetic models. The models have then been reduced through automated means to enable multidimensional simulation of the combustion characteristics of such fuels in real combustors. Such reliable kinetic models, validated against fundamental data derived from laminar flames using idealized flow models, are key to the development and design of optimal combustors and fuels. The models provide direct information about the relative contribution of different molecular constituents to the fuel performance and can be used to assess both combustion and emissions characteristics

An evidence based efficacy and safety assessment of the ethnobiologicals against poisonous and non-poisonous bites used by the tribals of three westernmost districts of West Bengal, India: Anti-phospholipase A2 and genotoxic effects.

IntroductionTo explore the ethnobiological wisdom of the tribals of three western districts of West Bengal, India against poisonous and non-poisonous bites and stings, a quantitative approach was adopted. These age-old yet unexplored knowledge can be utilized in finding lead-molecules against poisonous and non-poisonous animal-bites. Further, an evidence-based approach is needed to assess the venom-neutralization ability of plants by experimental studies.Materials and methodsDuring 2008-2009 and 2012-2017, 11 ethnomedicinal surveys were carried out to explore the use of medicinal flora and fauna via conducting open semi-structured interviews with 47 traditional healers (THs) or informants. The retrieved dataset was statistically evaluated using seven quantitative-indexes: use-value (UV), informants'-consensus-factor (ICF), fidelity-level (FL), relative-importance (RI), cultural importance-index (CI), index of agreement on remedies (IAR) and cultural agreement-index (CAI). Anti-phospholipaseA2 (PLA2) properties of selected plant extracts were also examined. In addition, the cytotoxicity and genotoxicity of the water extract of the plants showing high FL as well as significant PLA2 inhibitory potential were investigated using Allium cepa root tip assay.ResultsA total of 41 traditional-formulations (TFs) containing 40 plant species (of 39 genera from 28 families) and 3 animal species were prescribed by the THs. Fabaceae exhibited most number of medicinal plants. Piper nigrum (1.78) and Apis cerana indica and Crossopriza lyoni (both 0.21) exhibited the highest UV among the plants and the animals respectively. Stinging of centipede and dog/cat/hyena bite displayed highest ICF (1.00 each). Among the plants, the maximum RI (0.91) and CI (4.98) values were observed for Aristolochia indica. IAR (1.00) was recorded maximum for Achyranthes aspera, Gloriosa superba, Lycopodium cernuum, Smilax zeylanica and Streblus asper. Maximum CAI value was noted for Piper nigrum (5.5096). Among the animals, Apis cerana indica (0.31) and Crossopriza lyoni (1.52) displayed the highest RI and CI values respectively. Crossopriza lyoni (0.99) and Apis cerana indica (1.3871) exhibited maximum IAR and CAI values respectively. Plants showing higher FL exhibited higher anti-PLA2 activity via selective inhibition of human-group PLA2. In addition, Allium cepa root tip assay has indicated the safety and/or toxicity of the plant parts prescribed by the THs. Root water extracts of Aristolochia indica and Gloriosa superba exhibited significant genotoxicity and cytotoxicity.ConclusionsThree western districts of West Bengal is the natural abode for many tribal and non-tribal communities. A noteworthy correlation was established between the plants used against poisonous-bites and their anti-PLA2 activity. A few plant parts used by the THs also exhibited high toxicity. Such alternative medical practices serve as the only option in these underprivileged and backward areas during medical-exigencies

Synthesis, Characterization, and Antimicrobial Activity Screening of Some Novel 3‑(2-(3-(Substituted benzyloxy)oxetan-3-yl)-3-fluorophenoxy)-8-fluoro-2-methylquinoline Derivatives as Potential Antimycobacterial Agents

Microbial infections remain a grave threat to global health security due to increasing antibiotic resistance. The coronavirus pandemic has increased the risk of microbial infection. To combat these infections, the search for new therapeutic agents is in high demand. A series of new 3-(2-(3-(substituted benzyloxy)oxetan-3-yl)-3-fluorophenoxy)-8-fluoro-2-methylquinoline (9a–i) derivatives have been synthesized. The structure of synthesized compounds was analyzed by spectroscopic methods. The newly synthesized oxetanyl-quinoline derivatives were evaluated for in vitro antibacterial activity against Escherichia coli (NCIM 2574), Proteus mirabilis (NCIM 2388), Bacillus subtilis (NCIM 2063), Staphylococcus albus (NCIM 2178), and in vitro antifungal activity against Aspergillus niger (ATCC 504) and Candida albicans (NCIM 3100). Six oxetanyl-quinoline derivatives 9a, 9b, 9c, 9d, 9e, and 9h have shown good antibacterial activity against P. mirabilis with MIC 31.25–62.5 μM, 3-(((3-(2-fluoro-6-((8-fluoro-2-methylquinolin-3-yl)oxy)phenyl)oxetan-3-yl)oxy)methyl)benzonitrile (9f) reporting comparable activity against P. mirabilis with respect to the standard drug streptomycin. Compound 9a also showed good activity against B. subtilis with MIC 31.25 μM. The eight compounds 9a, 9b, 9d, 9e, 9f, 9g, 9h, and 9i have shown good antifungal activity against A. niger. The synthesized compounds were also screened for antimycobacterial activity against Mycobacterium tuberculosis H37Rv by MTT assay. Among the nine derivatives, compounds 9b, 9c, 9d, 9f, 9g, 9h, and 9i showed excellent antimycobacterial activity with MIC 3.41–12.23 μM, and two derivatives showed good activity with MIC 27.29–57.73 μM. All the derivatives were further evaluated for cytotoxicity against the Vero cell line and were found to be nontoxic. The in silico study of compounds 9a–i was performed against ATP synthase (PDB ID: 4V1F) and most of the compounds showed the stable and significant binding to ATP synthase, confirming their plausible mode of action as ATP synthase inhibitors. Thus, the significant antimycobacterial activity of 3-(2-(3-(substituted benzyloxy)oxetan-3-yl)-3-fluorophenoxy)-8-fluoro-2-methylquinoline derivatives has suggested that the oxatenyl-quinoline compounds could assist in the development of lead compounds to treat mycobacterial infections

Tungsten/boron nitride multilayers for XUV optical applications

International audienc

Magnesium-silicide-based multilayers for soft x-ray optics

International audienc

Covalent Organic Framework as a Metal-Free Photocatalyst for Dye Degradation and Radioactive Iodine Adsorption

Exploring a covalent organic framework (COF) material as an efficient metal-free photocatalyst and as an adsorbent for the removal of pollutants from contaminated water is very challenging in the context of sustainable chemistry. Herein, we report a new porous crystalline COF, C6-TRZ-TPA COF, via segregation of donor–acceptor moieties through the extended Schiff base condensation between tris(4-formylphenyl)amine and 4,4′,4″-(1,3,5-triazine-2,4,6-triyl)trianiline. This COF displayed a Brunauer–Emmett–Teller (BET) surface area of 1058 m2 g–1 with a pore volume of 0.73 cc g–1. Again, extended π-conjugation, the presence of heteroatoms throughout the framework, and a narrow band gap of 2.2 eV, all these features collectively work for the environmental remediation in two different perspectives: it could harness solar energy for environmental clean-up, where the COF has been explored as a robust metal-free photocatalyst for wastewater treatment and as an adsorbent for iodine capture. In our endeavor of wastewater treatment, we have conducted the photodegradation of rose bengal (RB) and methylene blue (MB) as model pollutants since these are extremely toxic, are health hazard, and bioaccumulative in nature. The catalyst C6-TRZ-TPA COF showed a very high catalytic efficiency of 99% towards the degradation of 250 parts per million (ppm) of RB solution in 80 min under visible light irradiation with the rate constant of 0.05 min–1. Further, C6-TRZ-TPA COF is found to be an excellent adsorbent as it efficiently adsorbed radioactive iodine from its solution as well as from the vapor phase. The material exhibits a very rapid iodine capturing tendency with an outstanding iodine vapor uptake capacity of 4832 mg g–1

Measurement of prompt D+D^+ and Ds+D^+_{s} production in pPbp\mathrm{Pb} collisions at sNN=5.02 \sqrt {s_{\mathrm{NN}}}=5.02\,TeV

International audienceThe production of prompt $D^+$ and $D^+_{s}$ mesons is studied in proton-lead collisions at a centre-of-mass energy of $\sqrt {s_{\mathrm{NN}}}=5.02\,$TeV. The data sample corresponding to an integrated luminosity of $(1.58\pm0.02)\mathrm{nb}^{-1}$ is collected by the LHCb experiment at the LHC. The differential production cross-sections are measured using $D^+$ and $D^+_{s}$ candidates with transverse momentum in the range of $0<p_{\mathrm{T}} <14\,\mathrm{GeV}/c$ and rapidities in the ranges of $1.5<y^*<4.0$ and $-5.0<y^*<-2.5$ in the nucleon-nucleon centre-of-mass system. For both particles, the nuclear modification factor and the forward-backward production ratio are determined. These results are compared with theoretical models that include initial-state nuclear effects. In addition, measurements of the cross-section ratios between $D^+$, $D^+_{s}$ and $D^0$ mesons are presented, providing a baseline for studying the charm hadronization in lead-lead collisions at LHC energies