Wild Brazilian Mustard (Brassica juncea L.) Seed Oil Methyl Esters as Biodiesel Fuel

Wild mustard (Brassica juncea L.) oil is evaluated as a feedstock for biodiesel production. Biodiesel was obtained in 94 wt.% yield by a standard transesterification procedure with methanol and sodium methoxide catalyst. Wild mustard oil had a high content of erucic (13(Z)-docosenoic; 45.7 wt.%) acid, with linoleic (9(Z),12(Z)-octadecadienoic; 14.2 wt.%) and linolenic (9(Z),12(Z),15(Z)-octadecatrienoic; 13.0 wt.%) acids comprising most of the remaining fatty acid profile. The cetane number, kinematic viscosity, and oxidative stability (Rancimat method) of the methyl esters was 61.1, 5.33 mm² s⁻¹ (40 °C) and 4.8 h (110 °C), respectively. The cloud, pour and cold filter plugging points were 4, −21 and −3 °C, respectively. Other properties such as acid value, lubricity, free and total glycerol content, iodine value, Gardner color, specific gravity, as well as sulfur and phosphorous contents were also determined and are discussed in light of biodiesel standards ASTM D6751 and EN 14214. Also reported are the properties and composition of wild mustard oil, along with identification of wild mustard collected in Brazil as Brassica juncea L. (2n = 36) as opposed to the currently accepted Sinapis arvensis L. (2n = 18) classification. In summary, wild mustard oil appears to be an acceptable feedstock for biodiesel production. Disclaimer: Product names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable.     

Prediction of unburnt carbon in tangentially fired boiler using Indian coals

Accurate prediction of percentage unburnt carbon in fly ash in the case of high ash content Indian coal, at the design stage, is generally difficult. In the present paper, a large number of laboratory test data and site data are used to understand the mechanism of unburnt carbon in fly ash as well as in bottom ash. Rigorous statistical analysis of the performance data taken from tangentially fired boilers shows that empirical correlation between a combination of coal properties and percentage unburnt carbon in fly ash exist. Equations to predict percentage unburnt carbon in fly ash and bottom ash have been proposed.     

Reaction of sulfur mustard gas,soman and agent VX with nanosized anatase TiO2 and ferrihydrite

Homogeneous hydrolysis of titanium oxo‐sulfate and iron(III) sulfate has been used to prepare anatase TiO₂ and ferrihydrite with high specific surface area. Resulting samples were characterised by specific surface area (Brunauer–Emmett–Teller method) and porosity (Barrett–Joyner–Halenda method) measurements, X‐ray powder diffraction (XRD) and scanning electron microscopy (SEM). The samples of anatase TiO₂ and ferrihydrite were evaluated for their ability to degrade chemical warfare agents (sulfur mustard gas, soman and agent VX) to non‐toxic products. The largest percentage of mustard gas converted into non‐toxic products after the completion of the reaction was 99%. Copyright © 2005 Society of Chemical Industry     

A thermal investigation on coals from Assam (India)

A thermal characterization of two coal samples from Ledo and Tikak collieries of Makum coalfield, Assam, India using XRD, FT-IR, and TGA was reported in this paper. The coal samples were heated for 20, 40 and 60 min in a 1000-watt heater (temperature ∼ 250 °C) in presence of air and characterized by XRD and FT-IR spectroscopy. Both the coals contain amorphous and crystalline phases. The raw coals also contain very small peaks due to quartz, calcite, gypsum, pyrite, and chlorite. The XRD patterns were found to change upon heating. In the coals heated for 20 and 40 min, it was observed that both amorphous and crystalline parts are common in them; crystalline part being the major one in the 40 min heated samples. The XRD patterns of the samples heated for 60 min indicate the presence of major quantities of α-quartz, hematite, and chlorite in them. They also show some new peaks, which are assigned to be kaolinite, illite, magnetite and very small in comparison to the amorphous portion in raw coals. α-quartz was found to be most stable crystalline phase of silica in the coals. The crystallinity % (X-ray) of the coals heat-treated for different times was determined and found to be increasing with time of heating. The FT-IR spectra of raw and heat-treated coal samples at 250 °C were also recorded and compared. The spectra were observed to be almost similar and it was observed that few functional groups disappear on heating at 250 °C. The same coal samples were also characterized by thermogravimetric analysis (TGA) and differential thermal analysis (DTA) techniques. On heat treatment in air atmosphere up to 800 °C, 20–27% weight loss occurs due to removal of various volatile materials. DTA results indicate the chemical reactivity of the coal sample initially at 80–110 °C due to loss of water, and two other major reactions at around 420 and 530 °C due to primary and secondary volatization.     

Comparison of three chosen vegetables with others from South East Asia for their lutein and zeaxanthin content

Three local leafy vegetables chekup manis (Sauropus androgynus), West Indian pea tree leaves (Sesbania grandiflora (L.) Pers.), and drumstick tree leaves (Moringa oleifera), are consumed by local South East Asian populations and are believed to have beneficial effects on improved vision and prevention of eye diseases. High performance liquid chromatography equipped with photodiode array detection was used to investigate their lutein and zeaxanthin contents, which were compared with those from other commonly found vegetables in the region. It was found that these three leafy vegetables contained significantly higher amounts of lutein namely, 19.5, 28.3, and 24.8 mg/100 g edible fresh leaves, respectively, compared to other vegetables in the region. It was also found that cooking in boiling water increase the extractable lutein content in chekup manis by almost 20%, within 4 min.     

Systematic evaluation of natural phenolic antioxidants from 133 Indian medicinal plants

Total antioxidant capacities of 133 Indian medicinal plant species sampled from 64 families were assessed by ABTS, DPPH and FRAP assays, and their total phenolic contents measured by Folin–Ciocalteu assay. These species exhibited a broad range of antioxidant activities, varying from 0.16 to 500.70 mmol TEAC/100 g DW in the ABTS assay. The antioxidant activity values similarly varied with the DPPH and FRAP assays. Significant and positive linear correlations were found between total antioxidant capacities and phenolic contents (R = 0.89–0.97), indicating that phenolics were the dominant antioxidant constituents in the tested medicinal plants. Preliminary identification of the major phenolic compounds from 83 selected medicinal plants by reversed-phase HPLC revealed phenolic acids, tannins, flavonoids, curcuminoids, coumarins, lignans, and quinines. The fruit of Terminalia chebula, pericarp of Punica granatum and gall of Rhus succedanea showed very high levels of hydrolysable tannins, and the gum of Acacia catechu presented very high levels of catechin and epicatechin in addition to tannins. Major phenolics in many of the medicinal plants were identified for the first time (e.g., Euphorbia lathyrus, Ipomoea turpethum, and Picrorrhiza kurroa). This systematic investigation of a large number of Indian medicinal plants proved important for understanding their chemical constituents and functionality in Ayurvedic medicine, and contributes to the search for natural sources of potent antioxidants.     

Activity-guided isolation and identification of free radical-scavenging components from an aqueous extract of Coleus aromaticus

An activity-directed fractionation and purification process was used to identify the DPPH (l,l-diphenyl-2-picrylhydrazyl) free radical-scavenging components of Coleus aromaticus Benth. Fresh leaves of C. aromaticus were extracted with water and then separated into hexane, ethyl acetate, and water fractions. Among these, only the ethyl acetate phase showed strong DPPH radical-scavenging activity in vitro, when compared with water and hexane phases. The ethyl acetate fraction was then subjected to separation and purification using Sephadex LH-20 chromatography. Three compounds showing strong DPPH radical-scavenging activity were shown, by spectral methods (¹H NMR, ¹³C NMR, and MS) and by comparison with literature values, to be rosmarinic acid, chlorogenic acid and caffeic acid. In addition, HPLC identification and quantification of isolated compounds were also performed. Rosmarinic acid was found as a major component and principally responsible for the radical-scavenging activity of C. aromaticus.     

蒙脱土有机改性对丁基橡胶复合材料微观结构与性能的影响

采用季铵盐有机改性蒙脱土(OMMT)与丁基橡胶(IIR)机械共混和硫化制备成复合材料。研究了蒙脱土有机改性前后对复合材料的微观结构、力学和芥子气防护性能的影响。透射电镜(TEM)和X射线衍射(XRD)显示IIR/OMMT复合材料为插层型纳米复合材料,而IIR/MMT为未插层的微米复合材料。复合材料的微观结构和填料的界面活性对其力学性能影响重大,IIR/OMMT复合材料的力学性能明显优于IIR/MMT复合材料的力学性能。添加有机或无机蒙脱土都可使芥子气在丁基橡胶中的扩散系数显著降低。而芥子气在IIR/OMMT中的扩散系数更低,这显示出IIR/OMMT复合材料的芥子气防护性能更加优异。     

Determinants of software quality in offshore development - An empirical study of an Indian vendor

Context

Cost advantage has been one of the primary drivers of successful offshoring engagements of Indian software and services companies. However, the emphasis has shifted to the ability of the vendors to provide high quality over cost advantage in delivering software products and services. Meeting high quality requirements of the clients is a challenge due to the very nature of development and delivery of software through offshoring.

Objective

The objective of this research paper is to identify and evaluate the key determinants of quality in the case of software projects delivered through offshoring model.

Method

A detailed survey was conducted among project managers/project leaders (leads) of a leading midsize Indian IT services company to evaluate the relationship of the determinants on the attributes of quality.

Results

Out of six determinants, our research reveals requirements uncertainty has significant association with all the attributes of quality. While process maturity and trained personnel have moderate association, communication and control, knowledge transfer and integration and technical infrastructure have relatively low association on software quality attributes in the case of offshoring.

Conclusion

It is concluded that the complexities in offshoring necessitates proper capturing of requirements. In addition high level of process maturity and availability of trained personnel to the project will help vendors to achieve software quality. The paper provides a set of implications for practice and directions for further research.