Spectral lines

From propolis of Lepidotrigona ventralis stingless bee collected in Tuyen Quang province, eight compounds were isolated and determined as lantanolic acid, moronic acid, (+)-eudesmin, (+)-yangambin, (+)-syringaresinol, (+)-pinoresinol, dihydroconiferyl alcohol and vanillin using NMR and MS spectral data. Compounds 1 and 2 showed significant cytotoxicity against HepG-2 cancer cell line with IC50 values of 25.84±0.48 and 39.92±1.14 ug/mL, respectively.

6p dianmotminh02 03-05-2024 2 1   Download

Phytochemical study of Knema pachycarpa leaves led to the isolation of ten compounds. Their chemical structures were determined as (7''R, 8''R)-hydnocarpin D, (7''R, 8''R)-hydnocarpin, sinaicitin, (-)-globulol, β-caryolanol, phytol, biochanin A, chrysoeriol, tanoside II and astragalin using NMR and MS spectral data. Among the isolates, (7''R, 8''R)-hydnocarpin showed good cytotoxic activity against KB, HepG-2, Lu and MCF-7 cancer cell lines with IC50 values from 13.99±0.62 ug/mL to 30.65±1.44 ug/mL.

6p dianmotminh02 03-05-2024 1 1   Download

The derived temperature dependences of the peak intensities, separations and half-widths of the separate spectral peaks in the A-band phonon progressions indicate the different trends for vibration-free zero-phonon electronic transition and vibration-related lower-energy electronic transitions to high vibrational levels of the ground electronic state – lower thermal damping and more softened phonon for the zero-phonon transition, also implying the extended defect origin of the A-band photoluminescence.

9p dianmotminh02 03-05-2024 3 1   Download

Part 1 book "Quantum physics in minutes the inner workings of our Universe explained in an instant" includes content: The birth of quantum physics, energy levels and spectral lines, particle physics, the wave function, the language of quantum physics, quantum physics and the Universe.

186p muasambanhan05 16-01-2024 4 0   Download

Continued part 1, part 2 of ebook "Recent advances in earthquake geotechnical engineering and microzonation" provides readers with content including: Chapter 5 - Site effects; Chapter 6 - Evaluation of liquefaction-induced deformation of structures; Chapter 7 - Seismic zonation methodologies with particular reference to the italian situation; Chapter 8 - Seismic microzonation; Chapter 9 - Dynamic analysis of solid waste landfills and lining systems;...

216p dieptieuung 19-07-2023 3 3   Download

Color perception is important for fish to survive and reproduce in nature. Visual pigments in the retinal photoreceptor cells are responsible for receiving light stimuli, but the function of the pigments in vivo has not been directly investigated in many animals due to the lack of color-blind lines and appropriate color-perception tests.

11p vinarcissa 21-03-2023 5 1   Download

In this paper, we demonstrate a homemade setup and an image processing algorithm to evaluate the image quality of optical systems working in the spectral region of 8-12 µm. The working principle of our approach relies on measuring the line spread function (LSF) and the modulation transfer function.

8p vispyker 14-11-2022 17 3   Download

Isatin, 1H -indoline-2,3-dione, an endogenous compound, is also a synthetically versatile molecule that possesses a diversity of biological activities including anticonvulsant, antibacterial, antifungal, antiviral, anticancer, and cytotoxic properties. Based on the promising cytotoxic activity studies on N -substituted isatin derivatives, a series of 18 derivatives of 2-(2,3-dioxo-2,3-dihydro-1H -indol-1-yl)-N -phenylacetamide were designed, synthesized, and characterized according to their analytical and spectral data.

9p langthannam 29-12-2021 12 1   Download

In addition, the novel bis-(1,2,4-triazole-3-thione) was reacted with the appropriate hydrazonoyl chloride in dioxane under reflux in the presence of triethylamine to give the corresponding bis-(1,2,4-triazolethiohydrazonoate). The structures of the new compounds were established based on elemental and spectral data. The mechanism of the studied reaction was also discussed.

15p langthannam 29-12-2021 4 0   Download

A series of 5-substituted-1,3,4-thiadiazole-based fluoroquinolone derivatives were designed as potential antibacterial and anticancer agents using a molecular hybridization approach. The target compounds 16–25 were synthesized by reacting the corresponding N-(5-substituted-1,3,4-thiadiazol-2-yl)-2-chloroacetamides with ciprofloxacin or norfloxacin. The purity and identity of the synthesized compounds were determined by the use of chromatographic and spectral techniques (NMR, IR, MS, etc.) besides elemental analysis.

20p tudichquannguyet 29-11-2021 8 2   Download

New derivatives of 2(3),9(10),16(17),23(24)-tetrakis-(6-methylpyridin-2-yloxy)phthalocyanine (Pc) (2b, 2c, and 2d) were synthesized and their structures were characterized by elemental analysis, IR, 1 H NMR, and high-resolution mass spectrometry. The spectral results were in line with the proposed structures. The photodegradation of Orange G (OG) dye in DMSO by the Pc derivatives was investigated. The compounds showed relatively high photodegradation rates that increased with increasing size of the central atoms.

11p tudichquannguyet 29-11-2021 17 1   Download

Lecture General Physics 2 - Chapter 27: Quantum Physics. After studying this section will help you understand: need for quantum physics, development of quantum physics, blackbody radiation, Wien’s displacement law, the ultraviolet catastrophe,...

55p diepchilang 26-08-2021 11 1   Download

The research in this thesis follows two directions: The first, using high performance computing currently available, we studied atomic and molecular emissions in astrophysical environment. The radiative transfer model was applied to explain the characteristics of the recombination line masers Hnα in the envelope of the star MWC 349A.

27p beloveinhouse01 15-08-2021 14 4   Download

Lecture Physics A2: Atomic physics. After studying this section will help you understand: particles in 3D potentials and the Hydrogen atom, spectral lines of Hydrogen atom, spectral lines of the alkali metal atoms, angular momentum, electron spin, atomic states, Pauli principle, building atoms and molecules,...

19p xusong 21-07-2021 13 1   Download

Lecture Physics A2: Atomic physics (Cont.). After studying this section will help you understand: orbital angular momentum, orbital magnetic momentum, spin angular momentum, spin magnetic momentum, Zeeman effect, finestructure of spectral line, Pauli exclusion principle, the periodic table, bosons and fermions,...

27p xusong 21-07-2021 9 1   Download

A new iridoid, (4S,5R,6S,7S,9S)-7,10,11-trihydroxy dihydronepetalactone (1) together with four known flavonoids including linarin, neodiosmin, neobudofficide and rhoifolin were isolated from aerial parts of Valeriana hardwickii Wall.. Chemical structures were elucidated by extensive spectroscopic analyses including ESI-HRMS and 1D, 2DNMR spectral data as well as by comparison with those reported in the literatures. Compound 1 showed no cytotoxic activity toward three human cancer cell lines (CCRF-CEM, MDA-MB-231 and HCT-116).

5p nguaconbaynhay11 16-04-2021 13 1   Download

In this study, we present the technique of tunable diode laser spectroscopy and the spectroscopic parameters of 13 lines of H2O in the 11980 -12260 cm−1 spectral region. Spectra were recorded at room temperature for a wide range of pressures (2 - 15 Torr for pure H2O and 50 - 760 Torr for H2O in air).

8p tamynhan5 10-12-2020 24 2   Download

A phytochemical investigation of whole Aspidistra letreae plants led to the isolation of 2Hchromen-2-one (1), α-tocopherol (2), (E)-phytol (3), asparenydiol (4) and (25S)-spirost-1β,3α,5β-triol (5). Their structures were determined on the basis of NMR spectral evidences and in comparison with the reported data. Of these, asparenydiol (4) was isolated from the genus Aspidistra for the first time. This is also the first report on the separation and structural determination of (25S)-spirost-1β,3α,5β-triol (5) as a pure compound.

9p nguaconbaynhay9 03-12-2020 12 3   Download

We study the morpho-kinematics in the nascent wind of AGB star R Doradus in the light of high Doppler velocity wings observed in the spectral lines of several species. We probe distances from the star between ∼10 and ∼100 au using ALMA observations of the emission of five different molecular lines. High Doppler velocity enhancements of the line emission are observed in the vicinity of the line of sight crossing the star, reminiscent of those recently interpreted as gas streams in the nascent wind of a similar AGB star, EP Aqr.

14p 12120609 23-03-2020 15 2   Download

Magneto-optical absorption coefficient (MOAC) in infinite square quantum well (SQW) is investigated by time-dependent perturbation method. The dependence of MOAC on the photon energy is calculated and graphically plotted. From the graphs showing this dependence, we obtained the spectral line width (the full-width at half maximum - FWHM) of the cyclotron-phonon resonance peaks using Profile method.

10p thuongdanguyetan19 05-02-2020 17 1   Download