The Spectrum of Doubly Ionized Tungsten (W III)

The spectrum of doubly ionized tungsten (W III) was produced in a sliding-spark discharge and recorded photographically on the NIST 10.7-m normal-incidence vacuum spectrograph in the 600–2680 Å spectral region. The analysis has led to the establishment of 71 levels of the interacting 5d⁴, 5d³ 6s and 5d² 6s² even configurations and 164 levels of the interacting 5d³ 6p and 5d² 6s 6p odd ones. A total of 2636 lines have been classified as transitions between the 235 experimentally determined levels. Comparison between the observed levels and those calculated from matrix diagonalizations with least-squares fitted parameters shows an rms deviation of ±87 cm⁻¹ for the even configurations and ±450 cm⁻¹ for the odd ones.     

High Accuracy Ultraviolet Index of Refraction Measurements Using a Fourier Transform Spectrometer

We have constructed a new facility at the National Institute of Standards and Technology (NIST) to measure the index of refraction of transmissive materials in the wavelength range from the visible to the vacuum ultraviolet. An etalon of the material is illuminated with synchrotron radiation, and the interference fringes in the transmittance spectrum are measured using a Fourier transform spectrometer. The refractive index of calcium fluoride, CaF₂, has been measured from 600 nm to 175 nm and the resulting values agree with a traditional goniometric measurement to within 1 × 10⁻⁵. The uncertainty in the index values is currently limited by the uncertainty in the thickness measurement of the etalon.     

Analysis of the First Spectrum of Ruthenium (Ru I)

The analysis of the first spectrum of ruthenium has been extended with the aid of digital computers. A total of 105 even and 206 odd levels are listed with observed Landé g-factors for 54 even and 148 odd levels. A complete list of approximately 3,400 classified lines in the range 2013 to 11484 A is presented. The ionization limit calculated from a two member series is 59410 cm⁻¹ or 7.364 v.     

Estimation of Concentration and Bonding Environment of Water Dissolved in Common Solvents Using Near Infrared Absorptivity

Integrated near infrared (NIR) absorbance has been used to determine the absorptivity of the υ₂ + υ₃ combination band of the asymmetric stretch (υ2) and the bending vibration (υ3) for water in several organic solvents. Absorptivity measured in this way is essentially constant across the absorption envelope and is found to be 336 L mol⁻¹ cm⁻¹ with a standard deviation of 4 L mol⁻¹ cm⁻¹ as estimated from a least squares fit of a straight line to data from water concentrations between 0.01 mol/L and 0.06 mol/L. Absorptivity measured from the peak maximum of the υ2 + υ3 combination band of water varies with the type of hydrogen bonding of the water molecule because the shape of the NIR absorption envelope changes with the hydrogen bonding.Because the integrated NIR absorptivity of the υ₂ + υ₃ combination band of water is essentially constant across the absorption envelope, the NIR absorption envelope reflects the distribution of hydrogen bonding of the water. The shape and location of the absorption envelope appear to be governed mostly by the number of hydrogen bonds from the water molecules to easily polarized atoms. Water that is a donor in hydrogen bonds to atoms which are not easily polarized (such as the oxygen of a typical carbonyl group) absorbs near 5240 cm⁻¹ to 5260 cm⁻¹. Water that donates one hydrogen bond to an easily polarized atom (such as a water molecule oxygen) absorbs near 5130 cm⁻¹ to 5175 cm⁻¹, and water that donates two hydrogen bonds to easily polarized atoms is estimated to absorb near 5000 cm⁻¹ to 5020 cm⁻¹. Water donating two hydrogen bonds to other water molecules may be said to be in a water-like environment. In no case does a small amount of water absorbed in a host material appear to have a water-like environment.     

Surface force spectroscopic point load measurements and viscoelastic modelling of the micromechanical properties of air flow sensitive hairs of a spider (Cupiennius salei)

The micromechanical properties of spider air flow hair sensilla (trichobothria) were characterized with nanometre resolution using surface force spectroscopy (SFS) under conditions of different constant deflection angular velocities (rad s⁻¹) for hairs 900–950 μm long prior to shortening for measurement purposes. In the range of angular velocities examined (4×10⁻⁴−2.6×10⁻¹ rad s⁻¹), the torque T (Nm) resisting hair motion and its time rate of change (Nm s⁻¹) were found to vary with deflection velocity according to power functions. In this range of angular velocities, the motion of the hair is most accurately captured by a three-parameter solid model, which numerically describes the properties of the hair suspension. A fit of the three-parameter model (3p) to the experimental data yielded the two torsional restoring parameters, S _3p=2.91×10⁻¹¹ Nm rad⁻¹ and =2.77×10⁻¹¹ Nm rad⁻¹ and the damping parameter R _3p=1.46×10⁻¹² Nm s rad⁻¹. For angular velocities larger than 0.05 rad s⁻¹, which are common under natural conditions, a more accurate angular momentum equation was found to be given by a two-parameter Kelvin solid model. For this case, the multiple regression fit yielded S _2p=4.89×10⁻¹¹ Nm rad⁻¹ and R _2p=2.83×10⁻¹⁴ Nm s rad⁻¹ for the model parameters. While the two-parameter model has been used extensively in earlier work primarily at high hair angular velocities, to correctly capture the motion of the hair at both low and high angular velocities it is necessary to employ the three-parameter model. It is suggested that the viscoelastic mechanical properties of the hair suspension work to promote the phasic response behaviour of the sensilla.     

Infrared emission of single-crystal calcite under broadband short-wavelength excitation

Our results demonstrate that broadband excitation of an oriented calcite single crystal with the radiation from a cw xenon lamp (incident power density of ～1 W/cm²) gives rise to secondary IR emission from the crystal surface. We have measured the IR emission spectrum of a calcite single crystal in two orientations in the range 500–1500 cm^?1 with a resolution of ～1 cm^?1 using a Fourier transform IR spectrometer. The spectrum shows sharp lines arising from IR-active (polar) vibrational transitions in the calcite crystal and can be interpreted in trems of a two-photon decay of a nonpolar vibrational state (A _1g mode) effectively excited through broadband visible pumping. We analyze the ways of raising the efficiency of the conversion of primary (visible) to secondary IR radiation. In particular, this might be achieved using photonic crystals and an excitation frequency near the maximum in their density of states. The new type of IR emission spectroscopy, taking advantage of broadband visible or UV excitation of molecular vibrations in bulk dielectric inorganic materials or materials infiltrated into the pore space of globular photonic crystals, appears to have considerable promise.     

Wavelength Shifts in Hg198 As a Function of Temperature

The wavelength shifts for the green (5460A) and blue (4358A) lines emitted from an electrodeless discharge lamp of Hg¹⁹⁸ have been studied as a function of the temperature of the water jacket of the source. The values of the wavelength shifts observed for the green and the blue lines are (8.5±3) 10⁻⁶ A/°C and (2±1) 10⁻⁶ A/°C, respectively.     

Infrared Absorption Spectrum of Nitrous Oxide (N2O) From 1830 cm?1 to 2270 cm?1

The frequencies of the vibration-rotation spectrum of N₂O have been measured from 1830 cm⁻¹ to 2270 cm⁻¹. A number of weak bands have been measured and assigned to “hot bands’’ and isotopic species in normal abundance. By using the Ritz principle and previously measured bands the bending frequency (v₂) is calculated as 588.78₀ cm⁻¹. Frequencies are given for lines arising from the three principal transitions found in this region.     

Rate of the Reaction NO+N,and Some Heterogeneous Reactions Observed in the Ion Source of a Mass Spectrometer

The rate of the reaction NO + N→ N₂+O has been measured to be 1.0±0.5×10¹³ cm³ moles⁻¹ sec⁻¹ at room temperature. The heterogeneous reactions N+O→NO and O + O→O₂ were observed to occur in the ion source of the mass spectrometer.     

Role of AgNPs in the enhancement of seed germination and its effect on plumule and radicle length of Pennisetum glaucum

The authors have investigated beneficial effects of 1 mM of silver nanoparticles (AgNPs) on agriculturally important plant Pennisetum glaucum (Bajara). The extracellular AgNPs were synthesised using Bacillus subtilis spizizenni and characterised using ultraviolet–visible absorption spectroscopy, Fourier transform infrared spectroscopy (FT‐IR) and transmission electron microscopy (TEM). Optical absorption spectrum showed characteristic peak of AgNPs at 423 nm. FT‐IR analysis of AgNPs showed peak at 3435 cm⁻¹, which indicates the presence of N–H group (primary, secondary amines and amides) on the surface of AgNPs. TEM studies indicate that synthesised AgNPs have average size of ∼2 nm. Energy dispersive X‐ray spectroscopy showed strong signal of Ag at 3 keV. Treatment of 1 mM AgNPs to the bajara seeds was found to be sufficient for excellent germination of seeds within 3 days. There was also significant increase in radicle and plumule length as compared with control bajara seeds according to statistical analysis by one‐way analysis of variance, followed by Tukey''s test. The percentage of AgNPs detected in root samples was 0.003% (by inductively coupled plasma atomic emission spectroscopy), which is negligible. There is still need to study the bioavailability and the type of interaction of AgNPs with plants, necessary for application in agriculture.Inspec keywords: transmission electron microscopy, ultraviolet spectra, scanning electron microscopy, nanofabrication, X‐ray diffraction, nanoparticles, visible spectra, silver, atomic emission spectroscopy, X‐ray chemical analysis, Fourier transform infrared spectra, statistical analysis, agricultureOther keywords: ultraviolet–visible absorption spectroscopy, transmission electron microscopy, Pennisetum glaucum, Bacillus subtilis spizizenni, energy dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy, optical absorption spectrum, plumule length, radicle length, silver nanoparticles, Tukey''s test, inductively coupled plasma atomic emission spectroscopy, statistical analysis, Bajara seeds, scanning electron microscopy, X‐ray diffraction, analysis of variance, electron volt energy 3.0 keV, time 3.0 d, Ag     

Superresolution of Fourier transform spectroscopy data by the maximum entropy method

The maximum entropy method (MEM) is applied to the interferogram data obtained using the technique of Fourier transform spectroscopy for estimating its spectrum with a resolution far exceeding the value set by the spectrometer. For emission line data, the MEM process is directly used with the interferogram data in place of the regular Fourier transformation process required in Fourier transform spectroscopy. It produces a spectral estimate with an enhanced resolution. For absorption data with a broad background spectrum, the method is applied to a modified interferogram which corresponds to the Fourier transform of the absorptance spectrum. Two results are presented to demonstrate the power of the technique: for the visible emission spectrum of a spectral calibration lamp and for the infrared chloroform absorption spectrum. Included in the paper is a discussion of the problems associated with practical use of the MEM.     

Foreword

The spectrum of a platinum hollow-cathode lamp containing neon carrier gas was recorded photographically and photoelectrically with a 10.7 m normal-incidence vacuum spectrograph. Wavelengths and intensities were determined for about 5600 lines in the region 1130–4330 Å. An atlas of the spectrum is given, with the spectral lines marked and their intensities, wavelengths, and classifications listed. Lines of impurity species are also identified. The uncertainty of the photographically measured wavelengths is estimated to be ± 0.0020 Å. The uncertainty of lines measured in the photoelectric scans is 0.01 Å for wavelengths shorter than 2030 Å and 0.02 Å for longer wavelengths. Ritz-type wavelengths are given for many of the classified lines of Pt II with uncertainties varying from ±0.0004 to ± 0.0025 Å. The uncertainty of the relative intensities is estimated to be about 20%.     

Green synthesis of silver nanoparticles using Zea mays and exploration of its biological applications

The biosynthesis of silver nanoparticles (AgNPs) has been proved to be a cost effective and environmental friendly approach toward chemical and physical methods. In the present study, biosynthesis of AgNPs was carried out using aqueous extract of Zea mays (Zm) husk. The initial colour change from golden yellow to orange was observed between 410 and 450 nm which confirmed the synthesis of AgNPs. Also, dynamic light scattering‐particle size analysis confirmed the average size to be 113 nm and zeta potential value of −28 kV. The morphology of synthesised Zm AgNPs displayed flower‐shaped structure, X‐ray diffraction pattern revealed the strongest peaks at 2θ = 38.6° and 64° which proved that the nanoparticle has the face centred crystalline structure. The Fourier transform infrared spectroscopy results showed strong absorption bands at 1394.53, 2980.02 and 2980.02 cm⁻¹ due to the presence of alkynes, carboxylic acids, alcoholic and phenolic groups. The maximum zone of inhibition was observed against Salmonella typhi (22 mm) and Candida albicans (18 mm). The synthesised nanoparticles exhibited more free radical scavenging activity than the aqueous plant extract. This is the first report on the synthesis of AgNP from Zm husk, delivers the efficient and stable Zm AgNPs through simple feasible approach toward green biotechnology.Inspec keywords: silver, nanoparticles, nanofabrication, light scattering, particle size, X‐ray diffraction, crystal structure, Fourier transform infrared spectra, absorption coefficients, free radicalsOther keywords: green synthesis, silver nanoparticles, biosynthesis, environmental friendly approach, aqueous extract, Zea mays husk, colour change, golden yellow, dynamic light scattering‐particle size analysis, average size, zeta potential value, flower‐shaped structure, X‐ray diffraction pattern, face centred crystalline structure, Fourier transform infrared spectroscopy, absorption bands, alkynes, carboxylic acids, alcoholic groups, phenolic groups, Salmonella typhi, Candida albicans, free radical scavenging activity, aqueous plant extraction, green biotechnology, size 113 nm, wavelength 410 nm to 450 nm     

The Spectrum of Singly Ionized Atomic Iodine (I ii)

The I ii spectrum has been excited in electrodeless lamps and photographed from 655 A to 11084 A. Wavelengths and estimated intensities are given for almost 2,400 lines. A revision and extension of the earlier analyses of this spectrum has increased the number of known even levels from 43 to 124, and the number of odd levels from 55 to 190. New g_J-factors are given for 46 levels, and the previous designations of 40 levels are changed. Improved measurements in the vacuum ultraviolet region give a correction of 7.4 cm⁻¹ to be subtracted from the values listed in Atomic Energy Levels, Vol. 3 (1958), for all levels above the ground configuration. The approximately 1,800 classified lines now include all of the strongest lines. The ¹S₀ of the ground configuration 5s²5p⁴ has been found, and this configuration has been fitted to intermediate coupling theory. Magnetic dipole transitions between levels of the ground configuration, ³P₂–¹D₂ (7282 A) and ³P₁–¹S₀ (4460 A), have been observed and their nature confirmed by the Zeeman effect. The line 5p^{4 3}P₂–¹D₂ shows hyperfine structure which is in approximate agreement with a theoretical calculation of the expected structure. New levels have been found for almost all higher configurations. All previously known series have been extended and new ones found. From one of the new series, 5p3(4S°)5−12g5G6°, the principal ionization energy for I ii (154304 ±1 cm⁻¹) has been derived. The results of the analysis are compared with theoretical expectations in a number of cases.     

Infrared Spectrum of the v2+ v6 Band of C13C12H6

The infrared spectrum of the v₂+v₆ band of C¹³C¹²H₆ has been analyzed and a value of B₀= 0.64865 ±0.00005 cm⁻¹ determined. When this value is combined with that found in recent work on isotopically normal ethane, a “r_s” value of 1.527±0.004 A for the carboncarbon bond distance is obtained. (Uncertainties are probable errors.)     

Absorption Bands of Carbon Dioxide From 5.3 to 4.6 Microns

Measurements have been made of the frequencies of the infrared absorption lines of CO₂ in the region from 1850 cm⁻¹ to 2150 cm⁻¹. Observations were made at various pressures and pathlengths up to a maximum of 72 meter-atmospheres. Vibration-rotation constants were obtained characterizing the transitions 11^1c0–000, 11^1d0–000, 03^1c0–000, 03^1d0–000, 200–01^1c0, I2^2c0–01^1c0, 12^2d0–01^1d0 for C¹²O₂. The 11^1c0–000 band due to the C¹³O₂ molecule was also measured.     

Anticancer activity of green synthesised AgNPs from Cymbopogon citratus (LG) against lung carcinoma cell line A549

The present study is designed to analyse the antibacterial and anticancer effects of silver nanoparticles (AgNPs) synthesised from the Cymbopogon citratus, (lemongrass) (LG‐AgNPs), which is widely used in ayurvedic drugs for treating various diseases. The LG‐AgNPs were synthesised and characterised using ultraviolet (UV) spectroscopy, Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD) and transmission electron microscopy (TEM) analysis. The characterised LG‐AgNPs was subjected to antimicrobial analysis by disc diffusion method against pathogenic bacteria and fungi. Furthermore, the cytotoxicity and anticancer activity of the LG‐AgNPs were assessed with lung alveolar carcinoma cell line A549. Results depict that UV–visible spectra of LG‐AgNPs showed strong absorption peak at 435 nm. The XRD study exposed LG‐AgNPs crystals, which confirmed with TEM analysis exhibiting particle size ranging between 17 and 25.8 nm. The FTIR spectra recorded peaks at 3347, 2126, 1639, 659, 598 and 553 cm⁻¹. The zone of inhibition study proves the LG‐AgNPs possessed both antibacterial and antifungal activities. 3‐(4, 5‐dimethyl thiazoyl‐2‐yl)‐(2,5‐diphenyltetrazolium bromide) results show the cytotoxicity effect of LG‐AgNPs in lung cancer cells. It also inhibited the cell migration and invasion at the dose of 25 µg ml⁻¹ by increasing the apoptotic gene expression. The results reveal LG‐AgNPs possess anticancer activities, proposing that it may be an alternative drug for allopathic drugs with lots of side effects used in lung cancer treatment.Inspec keywords: particle size, Fourier transform spectra, nanomedicine, cellular biophysics, infrared spectra, X‐ray diffraction, antibacterial activity, microorganisms, diseases, nanoparticles, transmission electron microscopy, lung, cancer, toxicology, drugsOther keywords: anticancer activity, green synthesised AgNPs, LG‐AgNPs crystals, lung carcinoma cell line A549, Cymbopogon citratus     

Enhanced cytotoxic activity of AgNPs on retinoblastoma Y79 cell lines synthesised using marine seaweed Turbinaria ornata

Retinoblastoma is the most common intraocular malignancy basically occurs among children below five. Certain ocular treatments such as surgery, radiation therapy and chemotherapy are more likely to cause side effects. Here, a rapid method of synthesising silver nanoparticles (AgNPs) from the brown seaweed Turbinaria ornata and its cytotoxic efficacy against the retinoblastoma Y79 cell lines was studied. The AgNPs synthesis was determined by Ultraviolet–visible spectroscopy and was further characterised by X‐ray diffraction, High‐resolution transmission electron microscopy, zeta potential, Energy‐dispersive X‐ray spectroscopy, thermogravimetric analysis, Fourier transform infrared spectrum and inductively coupled plasma‐mass spectroscopy techniques. The synthesised AgNPs were found to be very stable and finely dispersed. The total phenolic content of the synthesised AgNPs was estimated at 43±2.52 mg/g gallic acid equivalent and the nanoparticles exhibited good scavenging activity analysed by 2, 2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulphonic acid) assay. Moreover, cytotoxicity of synthesised AgNPs against in vitro retinoblastoma Y79 cell lines showed a dose‐dependent response with an inhibitory concentration (IC₅₀) of 10.5 µg/mL. These results suggest that AgNPs could be a promising anticancer agent with enhanced activity in ocular treatment.Inspec keywords: toxicology, silver, nanoparticles, cellular biophysics, cancer, nanomedicine, nanofabrication, X‐ray diffraction, transmission electron microscopy, electrokinetic effects, X‐ray chemical analysis, thermal analysis, Fourier transform infrared spectra, ultraviolet spectra, visible spectra, biomedical materials, mass spectroscopic chemical analysisOther keywords: cytotoxic activity, marine seaweed Turbinaria ornata, intraocular malignancy, silver nanoparticles, brown seaweed Turbinaria ornata, X‐ray diffraction, high‐resolution transmission electron microscopy, zeta potential, EDAX, thermogravimetric analysis, Fourier transform infrared spectrum, inductively coupled plasma‐mass spectroscopy, phenolic content, gallic acid, scavenging activity, in vitro retinoblastoma Y79 cell lines, dose‐dependent response, inhibitory concentration, anticancer agent, 2,2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulphonic acid) assay, nanotechnology‐based cancer diagnosis, ocular tumour treatment, ultraviolet‐visible spectroscopy, Ag     

Low-cost and fast synthesis of nanoporous silica cryogels for thermal insulation applications

Nanoporous silica cryogels with a high specific surface area of 1095 m² g⁻¹ were fabricated using tert-butyl alcohol as a reaction solvent, via a cost-effective sol–gel process followed by vacuum freeze drying. The total time of cryogel production was reduced markedly to one day. The molar ratio of solvent/precursor, which was varied from 5 to 13, significantly affected the porous structure and thermal insulating properties of the cryogels. The silica cryogels with low densities in the range of 0.08–0.18 g cm⁻³ and thermal conductivities as low as 6.7 mW (m·K)⁻¹ at 100 Pa and 28.3 mW (m·K)⁻¹ at 10⁵ Pa were obtained using this new technique.     

Biophytum sensitivum nanomedicine reduces cell viability and nitrite production in prostate cancer cells

Phytomedicine research received tremendous attention for novel therapeutic agent due to their safety and low cost. We assessed a novel nanoformulation of Biophytum sensitivum (BS), natural flavonoids for their improved efficacy and superior bioavailability against crude extract for prostate cancer cells (PC3). We prepared a nanomedicine of BS by nanoprecipitation method and size analysis via DLS and SEM revealed a range of 100–118 nm and surface zeta potential as −9.77 mV. FTIR was performed to evaluate functional for presence of carbonyl and aromatic rings, respectively. Human PC3 cells showed concentration at 0.5, 0.8, and 1 mg/ml dependent cytotoxicity 22, 39, and 56% for 24 h, whereas 43, 41, and 67% for 48 h of BS nanomedicine compared with crude 11, 22, and 53% for 24 h and 38, 31, and 60% for 48 h, respectively. Haemocompatibility of BS nanomedicine at the concentration of 0.5, 0.8, and 1 mg/ml did not show blood aggregation. Cellular uptake was confirmed using rhodamine‐conjugated BS nanomedicine for 48 h. Interestingly, BS nanomedicine 1 mg/ml decreases the nitrite productions in PC3 cells. Collectively, BS nanomedicine has the potential anti‐cancer agents with biocompatible and enhanced efficacy can be beneficial for the treatment of prostate cancerInspec keywords: nanomedicine, cancer, cellular biophysics, tumours, solubility, scanning electron microscopy, electrokinetic effects, Fourier transform infrared spectra, bloodOther keywords: Biophytum sensitivum, cell viability, nitrite production, prostate cancer cells, phytomedicine, therapeutic agent, natural flavonoids, pharmacological anti‐tumour agent, anti‐cancer agent, aqueous solubility, metabolism, dissolution rates, bioavailability, dynamic light scattering, scanning electron microscopy, surface zeta potential, FTIR, cytotoxicity, haemocompatibility, blood aggregation, cellular uptake level, cell membrane, cell nucleus, rhodamine‐conjugated BS nanomedicine, wave number 3358.07 cm^‐1 , wave number 2312.65 cm^‐1 , wave number 1737.86 cm^‐1 , wave number 1508.33 cm^‐1 , time 24 h, time 48 h