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61.
62.
Rajesh Kumar Verma Sanjeet K. Verma Umesh Pankaj Anand K. Gupta Khushboo Khan Karuna Shankar 《Natural product research》2015,29(3):297-300
Andrographis paniculata Nees is an annual erect herb with wide medicinal and pharmacological applications due to the presence of andrographolide and other active chemical constituents. The large-scale cultivation of the kalmegh is not in practice. The aim of this study was to establish sustainable production systems of A. paniculata cv CIM-Megha with the application of different bioinoculants and chemical fertilisers. A. paniculata herb and andrographolide yield in the dried leaves was found to be highest (218% and 61.3%, respectively) in treatment T3 (NPK+Bacillus sp.) compared with T1 (control). The soil organic carbon, soil microbial respiration, soil enzymes activity and available nutrients improved significantly with combined application of bioinoculants and chemical fertilisers. 相似文献
63.
Different Types of Nickel,Cobalt, and Manganese Complexes originating from 2‐Imidazolecarboxaldiimine of Triethylenetetraamine 下载免费PDF全文
The reactivity of the 2‐imidazolecarboxaldiimine of triethylenetetraamine (H2imida) towards divalent manganese, cobalt, and nickel ions differs. It forms a cationic nickel(II) complex by acting as a hexa‐dentate ligand, whereas the cobalt(II) complex formation took place by deprotonation of the H2imida forming a neutral complex with imida. Deprotonation of the ligand by H2imida by cobalt(II) ions caused quenching of the fluorescence emission at 312 nm, such a quenching effect was not observed with the nickel ions. On the other hand, a mononuclear manganese(II) complex of a new tetradentate ligand was formed by manganese(II) assisted intramolecular cyclization reactions of H2imida. 相似文献
64.
Sunitha V. Kishore Kumar A. Shankar B. Anil Kumar A. Krishna T. M. Lincoln Ch. A. Pochampalli J. 《Russian Journal of General Chemistry》2017,87(2):322-330
In the present study, a series of novel {6-[(1H-1,2,3-triazol-4-yl)methoxy]-3-methylbenzofuran-2-yl}(phenyl)methanones (7a–7o) have been synthesized using click chemistry approach. The structures of all newly synthesized compounds were characterized by FT-IR, 1H and 13C NMR, and MASS spectral data. Most of products demonstrated high antimicrobial activity.
相似文献65.
Following Elcrat [1] the phenomena associated with the sonic discontinuities in non-equilibrium gasdynamics have been studied here. The sonic wave in non-equilibrium gaseous medium propagates with the frozen speed of sound. The magnitude of discontinuities of the first derivatives of flow quantities in the unsteady flow of relaxing gas are shown to satisfy Riccatti equations along the orthogonal trajectories of surface S(t). In order to integrate them in full generality, they are transformed to an equation along the bicharacteristic curve in the characteristic manifold
S(t). These equations have been solved completely. The criteria for decay or blow up of sonic discontinuities are given and the particular cases of plane and spherical waves existing in an ideal dissociative gasdynamics have been discussed. In the case of planewave for uniform propagation, it is shown that the dissociating character of the gas is to decrease the critical time. Other cases of shock formation have been studied in detail. 相似文献
66.
Shankar M. Rama Mohan H. Viplava Prasad U. Harikrishna M. Pareswar Rao M. P. Ravindra A. 《Journal of heterocyclic chemistry》2014,51(4):1086-1093
A general synthetic approach has been developed for heterocyclic prostaglandins (PGF2α type) starting from the key intermediate ( 6 ). (±) 6 was obtained from (±) ‐Corey lactone. The key intermediate (±) 6 was, in turn, converted in to several new heterocyclic prostaglandins consisting of furan and thiophene moieties in ω‐side chain in two to three steps. Horner–Wadsworth–Emmons reaction and Grignard reaction as the key reactions in these transformations. 相似文献
67.
Loney RW Anyan WR Biswas SC Rananavare SB Hall SB 《Langmuir : the ACS journal of surfaces and colloids》2011,27(8):4857-4866
Adsorption of pulmonary surfactant to an air-water interface lowers surface tension (γ) at rates that initially decrease progressively, but which then accelerate close to the equilibrium γ. The studies here tested a series of hypotheses concerning mechanisms that might cause the late accelerated drop in γ. Experiments used captive bubbles and a Wilhelmy plate to measure γ during adsorption of vesicles containing constituents from extracted calf surfactant. The faster fall in γ reflects faster adsorption rather than any feature of the equation of state that relates γ to surface concentration (Γ). Adsorption accelerates when γ reaches a critical value rather than after an interval required to reach that γ. The hydrophobic surfactant proteins (SPs) represent key constituents, both for reaching the γ at which the acceleration occurs and for producing the acceleration itself. The γ at which rates of adsorption increase, however, is unaffected by the Γ of protein in the films. In the absence of the proteins, a phosphatidylethanolamine, which, like the SPs, induces fusion of the vesicles with the interfacial film, also causes adsorption to accelerate. Our results suggest that the late acceleration is characteristic of adsorption by fusion of vesicles with the nascent film, which proceeds more favorably when the Γ of the lipids exceeds a critical value. 相似文献
68.
69.
Based on a multiple scale analysis of a forced reaction-diffusion system leading to amplitude equations, we explain the existence of spiral wave and its photo-induced spatiotemporal behavior in chlorine dioxide-iodine-malonic acid system. When the photo-illumination intensity is modulated, breathing of spiral is observed in which the period of breathing is identical to the period of forcing. We have also derived the condition for breakup and suppression of spiral wave by periodic illumination. The numerical simulations agree well with our analytical treatment. 相似文献
70.
Konkala Karnakar Jilla Shankar Sabbavarapu Narayana Murthy Yadavalli Venkata Durga Nageswar 《Helvetica chimica acta》2011,94(5):875-880
Various phenyl and p‐tolyl allyl sulfone derivatives were prepared stereoselectively by reacting Baylis? Hillman acetates with sodium 4‐R‐benzenesulfinate (R=H, Me) in H2O. The reaction was very efficient in providing the corresponding sulfone derivatives in good to excellent yields (Table). 相似文献