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Two insect colonies of Elasmopalpus lignosellus were reared in our laboratory, the first being initiated from pupae obtained from a cornfield in the region of Sete Lagoas, Minas Gerais and the second from a cornfield in the region of Goiania, Goiás. From the two colonies, two extracts were prepared from the pheromone glands of virgin E. lignosellus females. The extract obtained from the first colony was designated as extract 1 while the extract obtained from the second colony was designated as extract 2. Extract 1 was analyzed by gas chromatography-mass spectrometry (GC-MS) with (Z)-9-hexadecenyl acetate [(Z)-9-HDA] and (Z)-11-hexadecenyl acetate [(Z)-11-HDA] being identified and confirmed by the formation of DMDS derivatives. In addition, a third acetate, which could be either (E)-8-hexadecenyl acetate [(E)-8-HDA] or (E)-9-hexadecenyl acetate [(E)-9-HDA] was detected by GC-MS. Extract 2 was analyzed by gas chromatography (GC) and gas chromatography-electroannetography (GC-EAD) revealing the presence of (Z)-11-HDA and (Z)-9-TDA. In addition, the same compounds elicited a response with the E. lignosellus male antenna obtained from the second insect colony. Electroantennography (EAG) screening with the male E. lignosellus antenna (obtained from the second insect colony) was conducted with the 23 possible tetradecenyl acetates (TDA) and 22 hexadecenyl acetates (HDA) as standards. Out of the 23 TDA isomers evaluated, only (Z)-9-TDA elicited a response and out of the 22 HDA [(Z) and (E) isomers gamma2 to delta13] evaluated only (Z)-11-HDA elicited a response. The acetate compositions of two extracts obtained from insects originating from the two states (Minas Gerais and Goiás) of Brazil were different from one another as well as from that obtained from insects in Tifton, GA, USA. The bioactivity data (GC-EAD) of the extract 2 differed from those reported for the Tifton, GA, USA population. These data suggest polymorphism in relation to the insect populations found in Brazil and in the USA. The possibility of the existence of an E. lignosellus sub-species cannot be ruled out. 相似文献
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Sn(IV)Cl4 catalyst provided a rapid and efficient deprotection method for the phenolic THP and MOM ethers and sequel intramolecular Friedel–Crafts alkylation reaction of THP and MOM protected chalcone epoxides under mild conditions. The reaction took 2–3 min to give the products in excellent yield (90–98%) at 0 °C without affecting the other functional groups. 相似文献
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Akram Ayesha Shahzady Tanzeela Gulab Hussain Shabbir Saad Nada A. Islam Md. Tanjir Ikram Muhammad 《Russian Journal of Applied Chemistry》2021,94(12):1585-1593
Russian Journal of Applied Chemistry - Liquid crystals polymers (LCPs) are aromatic polymers with unique properties which enable their usage in various applications. LCPs are herein discussed, in... 相似文献
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Sergio Antonio Fernandes Ricardo Natalino Poliana Aparecida Rodrigues Gazolla Márcio José da Silva Gulab Newandram Jham 《Tetrahedron letters》2012,53(13):1630-1633
Esterification yields were significantly improved using calix[n]arenes catalysts under simple conditions. p-Sulfonic acid calix[4]arene and p-sulfonic acid calix[6]arene were powerful organocatalysts in several esterification reactions, which showed activity comparable or even superior to other well-established acids catalysts, such as, sulfuric acid, p-toluenesulfonic acid, and p-hydroxybezenesulfonic acid described in the literature. 相似文献
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Kerehalli Vinayaka Prasad Hanumesh Vaidya Fateh Mebarek Oudina Khalid Mustafa Ramadan Muhammad Ijaz Khan Rajashekhar Choudhari Rathod Kirankumar Gulab Iskander Tlili Kamel Guedri Ahmed M. Galal 《印度化学会志》2022,99(8):100617
Due to the illuminating function of nanoliquids in several technological and medicinal domains, particularly in liquid transport processes known as peristalsis, inquisitive researchers have investigated the flow of peristaltic nanofluids. Consequently, the current study investigates the entropy production and magnetic influence on the peristaltic transport of heat and mass transport of Casson nanofluid in a non-uniform channel under convective circumstances. Utilizing the perturbation approach, fields of concentration, temperature, and velocity are derived from non-linear coupled partial differential equations (PDE). Entropy generation studies have been done. In addition, the influence of associated factors via specific physical terms, including the Sherwood number, the skin-friction coefficient, and the Nusselt number, for both Casson and Newtonian liquids, as well as the trapping phenomena, is visually examined. 相似文献
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Abbas Khan Iltaf Khan Momin Khan Hussain Gulab 《Russian Journal of Physical Chemistry B, Focus on Physics》2018,12(3):485-494
Due to the gradual increase in genetic related disease worldwide, the synthesis, characterization and physicochemical investigation of medicinal compounds such as thiobarbiturates and their derivatives is a highly desired area of research. Keeping their importance as medicinal compounds in mind, herein we report the synthesis and physicochemical characterization of five selected thiobarbiturate samples namely (MKA20 MKA21, MKA22, MKA23, MKA24) by using various physicochemical techniques. All the selected thiobarbiturates and their derivatives were synthesized by the reaction of diethyl thiobarbituric acid with different aromatic aldehydes. The synthesized thiobarbiturates and their derivatives were analyzed by various electroanalytical techniques, which gave us valuable information about the nature of thiobarbiturates and their derivatives. Further, the preliminary interaction of these thiobarbiturate with Deoxyribonucleic acid in aqueous solution was also investigated by using Ultraviolet-Visible spectrometry. On the basis of various results obtained, it can be said that most of their properties and extent of interaction with Deoxyribonucleic acid are varying with changing the alkyl groups on one hand and the functional groups on the other hand. 相似文献
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Repartitioning of co-solvents between particles of latex emulsions was investigated by means of a fluorescence method based
on the detection of the amount of co-solvent via the solvatochromic shift of the emission maximum of a fluorescent probe,
copolymerized at a low concentration. Complete repartitioning of co-solvents between particles of latex materials with a low
T
g
(ca. 25 °C) occurred within minutes. For a hydrophilic latex with a T
g
of 68 °C, equilibration was achieved within an hour. Repartitioning was faster for more hydrophobic co-solvents. For a hydrophobic
latex of similar T
g
, co-solvent repartitioning took place on the same time scale, but complete equilibration was not reached. Possibly, there
is an additional slow component in the repartitioning, or the prolonged presence of co-solvent causes a structural change
in the latex particles that affects the outcome of the experiment. 相似文献