Experimental comparison of performance and emission characteristics of 4-stroke CI engine operated with Roselle and Jatropha biodiesel blends

The environmental degradation, combined with the continuous depletion of the world's fossil fuel reserves, has forced the search for alternative fuels. This study was performed to investigate the performance of novel biodiesels in the CI engine. The experiments were performed at three different compressions ratios (16:1, 17:1, 18:1) and four loading conditions (25%, 50%, 75%, 100%). Different types of fuels such as jatropha biodiesel (JB), roselle biodiesel (RB), and ternary biodiesel (TB) were prepared and analyzed. The thermal performance of different fuels was analyzed in terms of brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), and exhaust gas temperature (EGT). The emission characteristics such as CO₂ emission, NO_x emission, and smoke emission were analyzed for all types of fuels. The results of these fuels in the engine were compared with mineral diesel (MD). The BTE was increased with increasing compression ratios and loads for all types of fuels. The BSFC was increased with increasing compression ratios but decreased with increasing loads. The increase in emission of NO_x was observed at higher compression ratios and loads. However, the CO₂ emission was decreased at higher loads and lower compression ratio. The performance curves achieved with a 20% jatropha biodiesel blend showed results that were approximate to those obtained with pure MD. The comparative analysis between different fuels showed that JB exhibit higher thermal performance as compared to other biodiesels. Therefore, JB can be a better alternative to conventional fuel.     

Identification of phytobioconstituents present in Simmondsia chinensis L. seeds extract by GC-MS analysis

Simmondsia chinensis L. commonly called as Jojoba and belongs to family Simmondsiaceae. It has shown positive pharmacological activities of these compounds which include antidiabetic, antirheumatic, anthelminthic, antipsoriatic, antioxidant, antiepileptic, antigonorrheal, analgesic, anti-inflammatory, and pesticidal activity of jojoba. The multifaceted action of numerous bioactives existing in the seed extract with therapeutic activity have attracted great research interest by pharmaceutical industries. n-hexane extract of Simmondsia chinensis L. (SC) Seeds was analysed by gas chromatography-mass spectroscopy for identification and characterization of phytobioconstituents and its therapeutic claim by traditional system. The major compounds discovered in SC seeds extract are cis-9-octadecen-1-ol (24.85%), 9-octadecen-1-ol, (Z)- (18.24%), Stigmast-5-en-3-ol (14.10%), Ergost-5-en-3-ol, (3-β)-ol (5.26%), (Z)-14-tricosenyl formate (5.24%), Thiositosteroldisulfide (3.64%), Silane, Dimethyl (dimethylpentyloxysilyloxy) tetradecyloxy- (3.41%), Ergost-5-ene, 3-methoxy-, (3β,24R)- (2.55%), Ergosta-5,22-dien-3-ol (2.22%), 1,19-eicosadiene (2.17%), Pentacosane (2.02%), Stigmasta-5,22-dien-3-ol (1.64%), 1,19-eicosadiene (1.57%), 9-octadecen-1-ol, (Z)- (1.46%), 9,19-cyclo-9β-lanostan-3β-ol, 24-methylene- (1.14%), (9Z)-9-octadecenyl palmitate (1.50%), Hexadecanoic acid, 9-octadecenyl ester, (Z) (1.37%), 9Z)-9-octadecenyl (9Z)-9-hexadecenoate (1.01%). The hexane extract of Simmondsia chinensis seeds comprises various polar and nonpolar phytobioconstituents. These compounds were established qualitatively via GC-MS evaluation. GC-MS reports will be promising in pharmaceutical sector in identification of variety of Phytobioconstituents in distinct plant extracts, polyherbal extract and the standardization of particular plant materials.     

Biomedical Applications of Scutellaria edelbergii Rech. f.: In Vitro and In Vivo Approach

In the current study, in vitro antimicrobial and antioxidant activities and in vivo anti-inflammatory and analgesic activities of Scutellaria edelbergii Rech. f. (crude extract and subfractions, i.e., n-hexane, ethyl acetate (EtOAc), chloroform, n-butanol (n-BuOH) and aqueous) were explored. Initially, extraction and fractionation of the selected medicinal plant were carried out, followed by phytochemical qualitative tests, which were mostly positive for all the extracts. EtOAc fraction possessed a significant amount of phenolic (79.2 ± 0.30 mg GAE/g) and flavonoid (84.0 ± 0.39 mg QE/g) content. The EtOAc fraction of S. edelbergii exhibited appreciable antibacterial activity against Gram-negative (Escherichia coli and Klebsiella pneumoniae) strains and significant zones of inhibition were observed against Gram-positive bacterial strains (Bacillus subtilis and Staphylococcus aureus). However, it was found inactive against Candida Albicans and Fusarium oxysporum fungal strains. The chloroform fraction was the most effective with an IC₅₀ value of 172 and 74 µg/mL against DPPH (1,1-Diphenyl-2-picryl-hydrazyl) and ABTS assays, in comparison with standard ascorbic acid 59 and 63 µg/mL, respectively. Moreover, the EtOAc fraction displayed significant in vivo anti-inflammatory activity (54%) using carrageenan-induced assay and significant (55%) in vivo analgesic activity using acetic acid-induced writing assay. In addition, nine known compounds, ursolic acid (UA), ovaul (OV), oleanolic acid (OA), β-sitosterol (BS), micromeric acid (MA), taraxasterol acetate (TA), 5,3′,4′-trihydroxy-7-methoxy flavone (FL-1), 5,7,4′-trihydroxy-6,3′-dimiethoxyflavone (FL-2) and 7-methoxy catechin (FL-3), were isolated from methanolic extract of S. edelbergii. These constituents have never been obtained from this source. The structures of all the isolated constituents were elucidated by spectroscopic means. In conclusion, the EtOAc fraction and all other fractions of S. edelbergii, in general, displayed a significant role as antibacterial, free radical scavenger, anti-inflammatory and analgesic agents which may be due to the presence of these constituents and other flavonoids.     

Vegetable Extracts and Nutrients Useful in the Recovery from Helicobacter pylori Infection: A Systematic Review on Clinical Trials

Helicobacter pylori (H. pylori) infections affect almost half of the world’s population, with gradually increasing incidence in developed countries. Eradication of H. pylori may provide significant benefits to the affected individual by healing a number of gastrointestinal and extra-digestive disorders. But due to increased microbial resistance and lack of patient adherence to the therapy, the eradication rate of H. pylori is below 80% with current pharmacological therapies. The usage of botanicals for their therapeutic purposes and medicinal properties have been increased in last decades. They can be use as alternative H. pylori treatments, especially against drug-resistant strains. Epidemiological studies have revealed that people with lower vegetable and micronutrient intake may be at increased risk of H. pylori infection. We have undertaken a review of clinical trials to evaluate the efficacy of vegetable extracts and micronutrients in patients with H. pylori. Various databases, such as Google Scholar, PubMed, Scopus, Web of Science, and the Cochrane Library, were searched for the articles published in English. A total of 24 clinical studies (15 for vegetable extracts and 9 for micronutrients) were selected to be reviewed and summarized in this article. Vegetable extracts (Broccoli sprouts, curcumin, Burdock complex, and Nigella sativa) and micronutrients (vitamin C and E) were not found to be as effective as single agents in H. pylori eradication, rather their efficacy synergized with conventional pharmacological therapies. Conversely, GutGard was found to be significantly effective as a single agent when compared to placebo control.     

On model for Darcy–Forchheimer 3D nanofluid flow subject to heat flux boundary condition

Journal of Thermal Analysis and Calorimetry - This paper provides a theoretical study of 3D nanofluid flow with zero nanoparticles mass and constant heat fluxes conditions. An incompressible...     

Numerical study of forced convection heat transfer across a cylinder with various cross sections

Journal of Thermal Analysis and Calorimetry - The thermal performance of an isothermal horizontal cylinder with different selected cross sections in cross-flow was investigated numerically. These...     

ZnSe-石墨烯/TiO_2声催化剂上罗丹明B降解与反应氧物种生成(英文)

Nanostructured ZnSe-graphene/TiO2 was synthesized by a hydrothermal-assisted approach. ZnSe-graphene/TiO2 exhibited favorable adsorption of rhodamine B, a wide wavelength absorption range, and efficient charge separation. Reactive oxygen species were generated by the oxidation of 1,5-diphenyl carbazide to 1,5-diphenyl carbazone. The sonocatalytic reaction mechanism was pro-posed. These findings potentially broaden the applications of sonocatalytic technologies.     

Differential equation approach for the energy average of the scattering function

An exact differential equation is given to evaluate the energy average of the scattering function. The advantage of the differential equation as compared to the earlier methods based on series expansion is that one has to evaluate only single sums over the complex poles of the S-matrix. Using Wigner’s semicircle law for the distribution of the real parts of the poles of the scattering matrix, the earlier expression for the energy average of the scattering function is rederived.