Three new pentacyclic triterpenoids, camaryolic acid (1), methylcamaralate (2) and camangeloyl acid (3) and six known compounds beta-sitosterol 3-O-beta-D-glucopyranoside (4), octadecanoic acid (5), docosanoic acid (6), palmitic acid (7), camaric acid (8) and lantanolic acid (9) were isolated from the aerial parts of Lantana camara. Structures of the new compounds were elucidated by spectroscopic and chemical methods. 相似文献
Two new esters of dammarane triterpenoids ixorene isovalerate (1), ixorene 3′,8′-dimethyloctanoate (2) and a new ursane-type triterpenoids Ixoroid acid (3) were isolated from the methanolic extract of flowers of Ixora coccinea Linn., along with the three known constituents. The structures of compounds 1 and 3 were elucidated on the basis of extensive 1D,2D NMR studies and mass spectrometry as 17β-dammara-12,20-diene-3β-isovelarate and 3β-hydroxy-18β-urs-12ene-29β-oic acid, respectively, whereas 2 was identified as 17β-dammara-12,20-diene-3β-3′,8′-dimethyloctanoate through 1H NMR and mass spectral data. Compounds 1, 2, 4 and 5 were evaluated for their in vitro cytotoxic activity, which exhibited weak activity against the 3T3, PC3 and HeLa cell lines with the IC50 value >30 μM. Antioxidant results of 1 – 5 revealed that only compound 5 showed antioxidant activity in DPPH radical scavenging inhibition with the IC50 1.31 × 10? 6 ± 0.005 μm mL? 1. Both activities are the first records of these isolated compounds from the flowers of Ixora coccinea Linn. 相似文献
Journal of Cluster Science - New facile way for production of antimicrobial wound healing dress was achieved using freshly fabricated bacterial cellulose (BNC) decorated with in situ formed silver... 相似文献
In this paper, we analyze the effect of heat transfer on the flow of tangent hyperbolic nanofluid in a ciliated tube (fallopian tube where embryo in blood make the development). This study will be beneficial for the researchers and medical experts in the field of embryology. The nanoparticles are beneficial to remove the cysts from the fallopian tube where development of embryo takes place. To resolves the ciliary flow problems, medical doctors use nanoparticles (drug delivery) that may create a temperature gradient. The heat transfer helps to optimize the energy for which the entropy generation is reduced. Therefore, in this research we discuss the heat transfer effect on tangent hyperbolic nanofluid and entropy generation due to ciliary movement. The governing partial differential equations are solved by HPM and software MATHEMATICA?. Effect of viscoelastic parameter, nanoparticles, cilia length and Brinkman number on the velocity, temperature and entropy generation has been illustrated with the help of graphs. Graphical results show that thermal conductivity of fluid increases by adding nanoparticles. The entropy generation due to nanoparticles will decrease the viscosity near the tube wall and blood through tube will flow with normal pressure.
Cyclic voltammetry has been employed to investigate the mixed micellar behavior of the binary mixtures of different zwitterionic surfactants such as 3-(N,N-dimethylhexadecylammonio)propane sulfonate (HPS), 3-(N,N-dimethyltetradecylammonio)propane sulfonate (TPS) and 3-(N,N-dimethyldodecylammonio)propane sulfonate (DPS) with three triblock polymers (L64, F127 and P65) by using 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) as an electroactive probe at 25 °C. Critical micellar concentration (cmc) has been determined from the plots of variation in peak current (ip) versus the total concentration of surfactant/triblock polymer. Diffusion coefficient of the electroactive species has also been reported. The regular solution theory approximation has been used to determine various micellar parameters of ideal systems. The variation in micellar mole fraction (X1) of the zwitterionic surfactant supports the formation of mixed micelles, which are rich in triblock polymer component in the surfactant rich region of the mixture and vice versa. The regular solution interaction parameter (β) suggests the formation of mixed micelles due to the synergistic interactions in case of HPS/TPS/DPS + F127/P65 systems and gets affected by EO/PO ratio of triblock polymers. 相似文献
Solar coronal loops are frequently accompanied by the field-aligned currents, which drive instabilities if the drift velocity u0 v A the Alfv′en velocity. For our choice of parameters, the critical threshold value of u0/v A is ~ 3.0 for growth and the corresponding current filling factor ~ 10-3-10-4. Below this value we are no longer in the kinetic regime.The coronal loops also have short-scale density gradients within each loop. The electron resonance in the presence of density gradient causes the drift mode to grow. We study the effect of these two free energy sources, the electron drift and the density gradient, in the presence of temperature anisotropy T⊥_α T∥_α. These effects simultaneously exist in the coronae. Using gyrokinetic theory, we investigate the influence of these effects, examine how they interplay with each other and study the consequent growth of the magnetosonic wave. We observe that kinetic instability driven by density gradient can be suppressed by field-aligned currents. The temperature anisotropy with chosen signatures causes further stabilizing effect. The results may prove useful to study the heating mechanism of solar coronal loops, acceleration of particles and confinement of particles in the thermonuclear reactors. 相似文献
Laser Induced Breakdown Spectroscopic (LIBS) technique was used to detect calcium and silicon in an unknown sample. In this method plasma was generated by Nd∶YAG laser of wavelength 1 064 nm with energy 400 mJ and pulse duration between 5~10 ns. The method was applied for the qualitative as well as quantitative analysis. In the qualitative analysis, the electron number density (Ne) of plasma containing calcium and silicon is determined showing that Ne of neutral particles is equivalent to 1016 (cm-3) whereas for ionized particles it is 1017 (cm-3). Plasma temperature is measured using Boltzmann plot method which must be greater than 10 000 k. Intensity ratio method is used for the quantitative analysis shows various elements in abundance with calcium and silicon in majority. 相似文献
Metal negatrode supercapattery (MNSC) is an emerging technology that combines the high energy storage capabilities of batteries with the high-power delivery of supercapacitors, thereby offering promising solutions for various applications, such as energy storage systems, electric vehicles, and portable electronics. This review article presents a comprehensive analysis of the potential of MNSCs as a prospective energy storage technology. MNSCs utilize a specific configuration in which the negatrode consists of a metal or metal-rich electrode, such as sodium, aluminum, potassium, or zinc, whereas the positrode functions as a supercapacitor electrode. The utilization of negatrodes with low electrochemical potential and high electrical conductivity is crucial for achieving high specific energy in energy storage devices, despite facing numerous challenges. The present study discusses the design and fabrication aspects of MNSCs, including the selection of appropriate metal negatrodes, electrolytes, and positrodes, alongside the fundamental operational mechanisms. Additionally, this review explores the challenges encountered in MNSCs and proposes solutions to enhance their performance, such as addressing dendrite formation and instability of metal electrodes. 相似文献