Search Results
You are looking at 1 - 10 of 18 items for
- Author or Editor: S. Alam x
- Refine by Access: All Content x
Abstract
A series of ethynyl and ethenyl end-capped imide resins were synthesised by the reaction of 9,9-bis(4-aminophenyl) fluorene (BAF) with pyromellitic dianhydride (PMDA)3/3′, 4,4′-benzophenone tetracarboxylic acid dianhydride (BTDA)/2,2-bis(3,4-dicarboxy phenyl) hexafluoropropane dianhydride (6F) and 3-ethynyl aniline/maleic anhydride. Structural characterisation was done by infra red and elemental analysis. Thermal characterisation was done by differential scanning calorimetry and thermogravimetric analysis. The decomposition temperatures of cured resins were above 200°C in nitrogen atmosphere. Char yield at 800°C ranged from 59–65.5%.
Effects of Meloidogyne incognita, Ascochyta rabiei, Xanthomonas campestris pv. cassiae and Rhizobium sp. were examined alone and in combination on the disease complex on chickpea. Individual inoculation of M. incognita, A. rabiei and X. campestris pv. cassiae caused significant reduction in plant growth while inoculation of Rhizobium sp. resulted in a significant increase in plant growth over control. Inoculation of pathogens in combination caused a greater reduction in plant growth than the damage caused by each of them singly. Application of pathogens prior to Rhizobium sp. caused a greater reduction in plant growth compared to plants where Rhizobium sp. was inoculated prior to pathogens. Use of M. incognita/A. rabiei or X. campestris pv. cassiae with Rhizobium sp. reduced root-nodulation. Application of Rhizobium sp. prior to pathogens resulted in greater nodulation compared to plants where Rhizobium sp. was inoculated simultaneously with pathogens. Rhizobium sp., A. rabiei and X. campestris pv. cassiae had adverse effect on galling and nematode multiplication. Maximum reduction in galling and nematode multiplication was observed when Rhizobium sp. along with A. rabiei plus X. campestris pv. cassiae was inoculated prior to M. incognita. Fungal and bacterial blight indices were 4 where A. rabiei and X. campestris pv. cassiae were inoculated alone. In other treatments where these pathogens were used in combination disease indices were 5.
Abstract
A series of silicon containing poly(ester imide)s [PEIs] were synthesized using novel vinyl silane diester anhydride (VSEA) and various aromatic and aliphatic dimines by two-step process includes ring-opening polyaddition reaction to form poly(amic acid) and thermal cyclo-dehydration process to obtain poly(ester imide)s. VSEA was synthesized by using dichloro methylvinylsilane and trimellitic anhydride in the presence of K2CO3 by nucleophilic substitution reaction. The PEIs were characterized by FTIR spectroscopy. The thermal properties of PEIs were investigated by using differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) methods. The prepared PEIs showed glass transition temperatures in the range of 320–350°C and their 5% mass loss was recorded in the temperature range of 500–520°C in nitrogen atmosphere. These had char yield in the range of 45–55% at 800°C.
Building Information Modelling (BIM) has become an emerging digital technology in the architecture, engineering and construction (AEC) industry. There is a growing demand on applying BIM for sustainable design including the building energy simulation (BES). Lack of sufficient interoperability has caused barriers to utilize the information from BIM for BES. In this study, the interoperability between BIM and four different BES tools (i.e., Ecotect, EQUEST, Design Builder and IES-VE) was explored by using a case study of a residential building in the design stage. The misrepresented information from BIM to multiple BES tools were identified based on six different categories of building information parameters. The research proposed an approach of creating gbXML file with an improved integrity of information in BIM. Overall, this study would lead to further work in developing platforms for improving the information transformation from BIM to BES.
Abstract
A series of hexachloronadimides containing phosphine oxide in the backbone were synthesized by the reaction of bis(3-amino phenyl) methyl phosphine oxide (BAP) with pyromellitic dianhydride (PMDA)/3,3’,4,4’-benzophenone tetracarboxylic acid dianhydride (BTDA)/2,2-bis(3,4-dicarboxy phenyl) hexafluoropropane dianhydride (6F) and hexachloronadic anhydride in glacial acetic acid/acetone. Structural characterisation of the resins was carried out by infrared, nuclear magnetic resonance spectroscopy and elemental analysis. Thermal characterisation of uncured resin was done by differential scanning calorimetry and thermogravimetric analysis. The decomposition temperature of uncured resins were above 31010C with T max 33010C in nitrogen atmosphere. Char yield at 800C ranged from 37–42%.
Abstract
The reinforcement of nano-barium titanate in ferrite filled poly-ether-ether-ketone (PEEK) composites caused a shift in the decomposition temperature, at which maximum mass loss occurred, to higher side and enhancement in char yield in thermogravimetric analysis. Loss tangent and glass transition temperature of ferrite filled PEEK composites were also found to be increased with the reinforcement of nano barium titanate. The effect of nano barium titanate on the melting behaviour of ferrite filled PEEK composites was negligible.
Genetic relationships among 24 genotypes of Hyophila involuta collected from five different natural populations of Mount Abu (Rajasthan) is analysed using RAPD and SSR markers. Based on efficiency parameters calculated for each marker system such as polymorphic information content (RAPD = 0.34; SSR = 0.66), marker index (RAPD = 2.78; SSR = 2.62) and resolving power (RAPD = 8.13; SSR = 2.23), the RAPD marker system shows higher values for some indices but microsatellites are more accurately reproducible than RAPD. Moreover, in case of the SSR, the average number of alleles was almost twice compared to RAPD. Mean coefficient of genetic differentiation between populations with RAPD was Gst = 0.269, while with SSR marker was Fst = 0.224. The UPGMA cluster analysis assembled genotypes into two main clusters with diverse levels of sub-clustering within the clusters. Also, the Mantel test showed no significant correlation between geographical and genetic distances. The observed moderately high genetic variability can be explained by efficient spore dispersal. Other factors such as reproductive mode, somatic mutation, continuous propagule recruitment and high degree of intermingling have great impact on the level of genetic variability in moss populations.
Abstract
The concentration and the sources of heavy metals (Pb, Cd, Zn and Cu) in house dust samples of nine selected houses of Jalil Town, Gujranwala, Pakistan are determined and a comparison with the concentration of these metals in respective street dust samples is given. Sources, exterior as well as interior are identified. The extent of contribution of lead in house dust from exterior sources and interior sources is calculated by determining the isotopic ratios in house dust, street dust and paint used in the houses. It is noticed in the case of well ventilated houses, that most of the heavy metal contribution is from the exterior sources. However, in less ventilated houses, contribution from the interior sources is also significant.
Growing research on beans suggest that they are good for health, as they reduce the risk and/or help in the management of chronic diseases. Beans are valuable parts of several dietary recommendations. Saponins, α-galactosides, phytates, and lectins are currently drawing attention because of their diverse properties, both adverse and beneficial. The aim was to determine the hepatotoxic effect of dry red kidney beans, i.e. Phaseolus vulgaris, on rabbits at 4 g kg–1, 6 g kg–1, and 8 g kg–1 dosing for the period of 30 days. The histopathological examination revealed inflammation of hepatocyte at all three doses along with congestion. The biochemical testing of liver enzymes revealed elevated alanine transaminase (ALT), aspartate transaminase (AST) and gamma-glutamyl transferase (γ-GT). The dose-dependent increase in liver enzymes indicates the hepatotoxic effect of dry red kidney beans, and various studies have demonstrated that lectins are the toxic components responsible for inflammation of body organs.
Abstract
Paste formulations of Volvariella volvacea (VV) were developed for its shelf-life enhancement. Egg stage fruiting bodies of mushrooms were used for preparation of salted, spiced, and their fermented pastes. Fermented paste formulations were developed using inoculation with Lactobacillus rhamnosus GG at 0.5% (w/w) and incubation for 2 days at 35 ± 2 °C. The unfermented VV paste was preserved with sodium benzoate of 0.065%, while fermented formulations were kept devoid of any chemical preservative. All formulations were packed in glass jars and retort bags, and thereafter treated in boiling water bath for one hour. The spiced, fermented VV paste scored highest in sensory evaluation and maximum crude protein and moisture contents, while lowest in contents of ash, fat, crude fibre, and carbohydrates. The fermented (salted and spiced) VV pastes showed variation in pH at 4 °C. Shelf life of 56 days was observed for fermented VV paste stored in glass jars under refrigerated conditions. The antioxidant analysis revealed that DPPH radical scavenging activity of fermented paste formulations increased significantly up to 21 days followed by gradual decrease until the 56th day, while total phenolic content of all paste formulations decreased with storage time. Hence, fermented spiced paste showed enhanced nutritive and antioxidative potential and shelf life up to 56 days.
