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The purpose of this study was to analyze and quantify spectral parameters, the absorption bands, specifically in the uv-visible region of some N-oxide ligands. From the spectra, the area under the absorption band, the molar absorptivity, the integrated absorption coefficient and the oscillator strength by the Gaussian approximation method were calculated for each of them, using the proposed evaluation by Drago and Figgs. According to the obtained results, it can be concluded that the heterocyclic compounds studied absorb very well electromagnetic radiation in the ultraviolet region. For the ligands QUI-NO and NIC-NO it was observed that there are two types of bands, primary and secondary, being transitions of type π → π * and n → π*, respectively. For DITBIS-NO, there was only one primary band (transition 1) and two additional shoulders, which had the highest observed absorbance coefficient. These ligands are expected as potential electron donors in complex systems whose purpose is to change the energy levels of the electronic system in order to promote a better utilization of the absorbed energy and therefore a better efficiency.

In this paper, the maximum achievable throughput of electromagnetic nanonetworks in the terahertz (THz) band (0.1–10 THz) is comprehensively investigated. On the one hand, the peculiarities of the THz-band channel are taken into account by capturing the impact of the molecular absorption loss on the signal propagation. On the other hand, a two-state medium access control protocol is utilized to reflect the behavior of energy-harvesting nano-devices with constrained harvesting rate and maximum transmission power $P_{0}$ . An ad-hoc nanonetwork is considered with $n$ identical randomly located nano-devices, and each is capable of utilizing $W$ Hz of bandwidth. When the node density of nanonetworks is low, the achievable throughput is $O (W P_{0} ( { (n\log n )^{({\alpha _{spr}-1}/{2})}}/{\exp (({ \alpha _{abs}}/{({n \log n})^{1/2}} ))}) )^{({1}/{2})}$ , where $\alpha _{spr}$ and $\alpha _{abs}$ refer to the spreading loss coefficient and the molecular absorption loss coefficient. When the node density of nanonetworks is very high, the interference among nano-devices governs the network behavior and the achievable throughput becomes $O (({W^{2} P_{0}/ {I(n)}}) ({ (n\log n )^{({\alpha _{spr}-1}/{2})}}/~{\exp (({ \alpha _{abs}}/{({n \log n})^{1/2}}) )} ))^{({1}/{2})}$ . For both the cases, the upper boundaries of the achievable throughput are analytically derived, and the numerical results are provided. Numerical results illustrate that the molecular absorption loss plays the main role when the nanonetwork is sparse, and the interference dominates when the nanonetwork node density is very high.

Molecular absorption bands are estimators of stellar activity and spot cycles on magnetically active stars. We have previously introduced a new color index that compare absorption strength of the titanium oxide (TiO) at 567 nm with nearby continuum. In this paper we implement this index to measure long-term activity variations and the statistical properties of the index in a sample of 302 solar-type stars from the HARPS planet search program. The results indicate a pattern of change in star's activity, covers a range of periods from 2 years up to 17 years., Comment: 17 pages, 95 figures, 2 tables, accepted for publication in MNRAS

Impulse response is vital for wireless communication analysis and modeling. This paper considers the impulse response of the terahertz band (THz band: 0.1–10 THz) for short range (1–100 cm) wireless communication. Earlier works derived the impulse response from transmittance by assuming a linear phase, which corresponds to a line-of-sight (LoS) propagation delay to a receiver. However, the linear phase leads to a symmetric impulse response before and after the LoS propagation delay. Physically, it is impossible for a signal to arrive before the LoS propagation delay since this violates causality. To address this issue, this study derives a phase function leading to an impulse response that satisfies causality. The validity of the derived model is verified with experimental THz band measurements (up to 2 THz), which show excellent agreement with the results predicted by the theory. From the impulse response, coherence bandwidth is found for both the entire THz band and its subbands. The results show significant variations in the coherence bandwidth as a function of the center frequency. Knowledge of these variations supports selection of the proper center frequency for wireless communications in the THz band.

Ingerir alimentos conocidos en Venezuela como guayaba (Psidium guajava) y pimentón (Capsicum annum L.), pueden estimular la fijación de Fe (II); en el organismo, por lo que, evaluar su participación y sinergia en el cuerpo es de suma importancia. La evaluación estuvo basada en una metodología de diseño no experimental, de tipo campo, con nivel descriptivo. Para ello, se trataron entre 30 a 35 g de cada especie, para la guayaba en diferentes disposiciones (trozos: t, jugo: j y residuo: r, para el pimentón (t) y para la mezcla de ambas especies (jugo y residuo). Después de digerir las muestras con HCl 6M a 100° C, se analizaron por espectroscopia de absorción atómica (EAA) y espectroscopia de absorción molecular (UV- visible) (EAM), acomplejando el Fe (II) con o-fenantrolina. Los resultados obtenidos sugieren que la guayaba presenta mayor concentración de Fe en el orden r>t>j. En el pimentón la concentración de Fe resultó ser mayor en los trozos en comparación con los valores obtenidos en la guayaba (trozos y jugo) y la mezcla de ambos con excepción del residuo de la guayaba y de la mezcla. Los resultados sugieren que la fruta y hortaliza estudiada pueden ser utilizadas como complemento en la dieta alimenticia del ser humano.

Two nanostructured hybrid materials are reported that include uncoated magnetic nanoiron oxides and magnetic nanoiron oxides treated with rose leaf extract. Atomic and molecular absorption ...

One of the problems for quantifying the amount of silicon available by molecular absorption is the elimination of chemical interference caused by available phosphorus. The aim of this work was to evaluate different organic acids in eliminating the interference caused by phosphorus in the quantification of available silicon by molecular absorption. The experiments were conducted in the Soil laboratory of the College of Agricultural Sciences at the Universidad de Córdoba, Colombia. For this work, different acids such as tartaric, citric, oxalic and malic were evaluated at two concentrations (0.8 and 1.33 mol L-1). Solutions containing silicon (1 mg L-1) and six concentrations of phosphorus were prepared (0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 mg L-1). The quantification of silicon was conducted by molecular absorption spectrophotometry using a Perkin Elmer Lambda XLS + at 660 nm. The results were subjected to the LSD tests and contrasts using the R software (Development Core Team, version 3.2.2).The results indicated that the oxalic, citric and malic acids at both concentrations produced lower overestimation of silicon in the presence of the P concentrations 0.6, 0.8 and 1.0 mgL-1 than the tartaric acid, which is commonly used as a reference to remove the P interference. One of the problems for quantifying the amount of silicon available by molecular absorption is the elimination of chemical interference caused by available phosphorus. The aim of this work was to evaluate different organic acids in eliminating the interference caused by phosphorus in the quantification of available silicon by molecular absorption. The experiments were conducted in the Soil laboratory of the College of Agricultural Sciences at the Universidad de Córdoba, Colombia. For this work, different acids such as tartaric, citric, oxalic and malic were evaluated at two concentrations (0.8 and 1.33 mol L-1). Solutions containing silicon (1 mg L-1) and six concentrations of phosphorus were prepared (0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 mg L-1). The quantification of silicon was conducted by molecular absorption spectrophotometry using a Perkin Elmer Lambda XLS + at 660 nm. The results were subjected to the LSD tests and contrasts using the R software (Development Core Team, version 3.2.2).The results indicated that the oxalic, citric and malic acids at both concentrations produced lower overestimation of silicon in the presence of the P concentrations 0.6, 0.8 and 1.0 mgL-1 than the tartaric acid, which is commonly used as a reference to remove the P interference.

Thermochemical processes of gaseous molecules SrI and BaI formation, which are used in the electrothermal molecular absorption determination of iodine, were studied using the method of thermodynamic simulation. The calculations made it possible to establish that gaseous molecules SrIg and BaIg are formed during the course of the thermal decomposition of gaseous SrI2g or BaI2g, respectively.

We derive new expressions for the connection probability and the average ergodic capacity to evaluate the performance achieved by multi-connectivity (MC) in an indoor ultra-wideband terahertz (THz) communication system. In this system, the user is affected by both self-blockage and dynamic human blockers. We first build up a three-dimensional propagation channel in this system to characterize the impact of molecular absorption loss and the shrinking usable bandwidth nature of the ultra-wideband THz channel. We then carry out new performance analysis for two MC strategies: 1) Closest line-of-sight (LOS) access point (AP) MC (C-MC), and 2) Reactive MC (R- MC). With numerical results, we validate our analysis and show the considerable improvement achieved by both MC strategies in the connection probability. We further show that the C-MC and R-MC strategies provide significant and marginal capacity gain relative to the single connectivity strategy, respectively, and increasing the number of the users associated APs imposes completely different affects on the capacity gain achieved by the C-MC and R-MC strategies. Additionally, we clarify that our analysis allows us to determine the optimal density of APs in order to maximize the capacity gain., Comment: Accepted to appear in IEEE ICC 2020

This letter develops a one-dimensional (1D) diffusion-based molecular communication system to analyze channel responses between a single transmitter (TX) and two fully-absorbing receivers (RXs). Incorporating molecular degradation in the environment, rigorous analytical formulas for i) the fraction of molecules absorbed, ii) the corresponding hitting rate, and iii) the asymptotic fraction of absorbed molecules as time approaches infinity at each RX are derived when an impulse of molecules are released at the TX. By using particle-based simulations, the derived analytical expressions are validated. Simulations also present the distance ranges of two RXs that do not impact molecular absorption of each other, and demonstrate that the mutual imfluence of two active RXs reduces with the increase in the degradation rate., 5 pages, 4 figures

This paper describes the effect of Atmospheric changes on the received signal level for an Urban Micro cell (Umi) environment, using Uniform Linear Array (ULA). The collective attenuation due to the rain and molecular absorption in dry air (including oxygen), induces a great estimation of the path loss and path loss exponent. However this additive attenuation is not modeled for all the existing 5G channel models as shown in our previous Survey [1], the only channel Models that took this phenomenon into account are the Close-In free Model (CI) and the ITU Radiocommunication (ITU-R) Model. The latter, does not give a collective estimation of the attenuation for all the atmospheric parameters [2][3], like the channel model CI provide. Moreover the CI Model is realized by researchers at New York University (NYU), by combining both computer simulation results and the measurements [4], then this model is established with a good calibtration. For all these reasons we choose to accomplish our study by using the CI model through the NYUSIM software.

This paper intends to give an overview about atmospheric changes effects on millimeter wave propagation, more precisely the collective attenuation caused by: dry air (including oxygen), water vapor, rain rate and haze/fog. Theoretical aspects of each parameter are presented throughout the paper and the attenuation statistics are estimated from meteorological data, for three Moroccan cities (Ifrane, Rabat, Laayoune) known to have an extreme atmospheric conditions, respectively in the three seasons: winter, spring and summer. We emphasize at the end, the role of each atmospheric parameter on deteriorating the mm-wave signal, which will provide further insights about the phenomena discussed.

In this paper, we present the revision of the cross-section database used for the retrieval of aerosol and gas species from remote sensing measurements by the GOMOS instrument onboard ENVISAT. The absorption cross-section spectra concern ozone, nitrogen dioxide and nitrogen trioxide, for which improved datasets have been published since the implementation of the original GOMOS cross-section database in preparation of the ENVISAT mission. We evaluate the molecular absorption cross-section spectra currently available for O3, NO2 and NO3, and we present and discuss our selection of datasets and the set-up of the revised absorption cross-section database, with the focus on these three gases. The objective is to provide an optimal characterization of their absorption spectrum over the UV-visible-near IR range used by AerGOM, a retrieval algorithm that was designed to optimize the retrieval of aerosol species from GOMOS measurements. Despite its application to the specific case of GOMOS, it is the aim of this work to cover a more general scope than this particular mission, and to provide an evaluation applicable to any other case of remote sensing experiment covering the UV to near IR range, possibly with a high spectral resolution.

In-vivo nano-biosensing has been attracting a lot of interest within the academic research community recently since it plays a major role in the development of personalized nano-medicine technologies and solutions. The implementation of new nano-biosensing systems inside the human body faces the major challenge of modeling the in-vivo communication channel. Several efforts have been reported recently to investigate the main factors that define the characteristics of the in-vivo communication channel. This paper outlines and discusses the factors that contribute to the path loss encountered by an EM wave in-vivo. These include spreading loss of the propagating wave, the loss due to molecular absorption by biological tissue, and the scattering from the body particles.

This work proposes the ultraviolet–visible molecular absorption spectroscopy as method of chemical–physical analysis, simple and economically viable for Cuba, for the sake of quantifying the superplasticizers adsorption in calcined clay. The superplasticizers Dynamon SX 32 and Dynamon SRC 20 were rehearsed (commercial name of the signature MAPEI), used in the industry of the construction in the country and four roasted clays of the locations of Yaguajay (3) and Pontezuela (1). Firstly the spectra were obtained for both superplasticizers and the longitude of wave for work was selected; then the calibration straight line were elaborated for the quantitative analysis and lastly, the method was proven in the four clays. For both superplasticizers the longitude of selected wave was 259 nm. The calibration straight line presented superior determination’s coefficients to 0.995 and variation’s coefficients for point inferior to 3%. The adsorption of the superplasticizers in the roasted clays oscillated between 40 and 60%. The results demonstrate the feasibility of using the method proposed for the analytic determination as well as the strong adsorption that these superplasticizers present in the roasted clays for the studied systems.

The introductory chapter leads the way towards the main steps of the present master’s thesis, and its scope is to theoretically address the aim of this thesis, which is to deal with the problems of huge propagation loss and the quite expected laws of attenuation and absorption. In addition, it encircles the study over the THz signaling as well as the communication systems, their foundations, and not only their linear and optics theory but also their utilization in nowadays. The second chapter examines the literature concerning the capacity of MIMO systems. Apart from that, it provides information about MIMO channel systems and their efficiency, in order to justify its usage in this particular thesis. The third chapter is concerned about the system channel models and attenuation. Besides that, it introduces the basic physical variable, which is the K-factor, helping with the modeling of these channels, among other ones. The end of this chapter reveals how the atmospheric factors, such as attenuation, re-radiation, spreading, climate, govern telecommunications. The fourth chapter presents the results of a MIMO experimental simulation, created in the MATLAB environment. Furthermore, it compares the beamforming and multiplexing MIMO capacity of two distinct models: the Hosseini’s and the Simplified one. Finally, it outlines state-of-the-art developments relevant to THz communications.

Cyclic trinuclear units (CTUs) based on Au(i), Ag(i) and Cu(i) cations, featuring near planar nine-membered coordination rings, represent an important class of metal-organic π-acids/bases with highly adjustable π-acidity/basicity. Their superior π-acidity/basicity coupled with Lewis-acidic and metalmetal bonding sites offers excellent attraction for a wide range of acidic/basic species, and usually followed by noticeable changes of luminescence or charge transfer behaviors. A series of representative cases from the past two decades have been selected herein for such cyclic trinuclear units in both oligomeric and polymeric systems. Their fascinating and profound potential applications related to π-acidity/basicity are highlighted, including molecular absorption and separation, luminescence sensing and detection, organic light-emitting diodes (OLEDs), metal-organic field-effect transistors (MOFETs), molecular wires, and catalysis. The challenges in improving the performance for practical application will also be discussed.

Radiation is a key process in the atmosphere. Numerous radiative transfer codes have been developed spanning a large range of wavelengths, complexities, speeds, and accuracies. In the infrared and microwave, line-by-line codes are crucial esp. for modeling and analyzing high-resolution spectroscopic observations. Here we present Py4CAtS - PYthon scripts for Computational ATmospheric Spectroscopy, a Python re-implementation of the Fortran Generic Atmospheric Radiation Line-by-line Code GARLIC, where computationally-intensive code sections use the Numeric/Scientific Python modules for highly optimized array processing. The individual steps of an infrared or microwave radiative transfer computation are implemented in separate scripts (and corresponding functions) to extract lines of relevant molecules in the spectral range of interest, to compute line-by-line cross sections for given pressure(s) and temperature(s), to combine cross sections to absorption coefficients and optical depths, and to integrate along the line-of-sight to transmission and radiance/intensity. Py4CAtS can be used in three ways: in the (Unix/Windows/Mac) console/terminal, inside the (I)Python interpreter, or Jupyter notebook. The basic design of the package, numerical and computational aspects relevant for optimization, and a sketch of the typical workflow are presented. In conclusion, Py4CAtS provides a versatile environment for "interactive" (and batch) line-by-line radiative transfer modeling.

Stellar, substellar, and planetary atmosphere models are all highly sensitive to the input opacities. Generational differences between various state-of-the-art stellar/planetary models are primarily because of incomplete and outdated atomic/molecular line-lists. Here we present a database of pre-computed absorption cross-sections for all isotopologues of key atmospheric molecules relevant to late-type stellar, brown dwarf, and planetary atmospheres: MgH, AlH, CaH, TiH, CrH, FeH, SiO, TiO, VO, and H2O. The pressure and temperature ranges of the computed opacities are between 10$^{-6}$--3000~bar and 75--4000~K, and their spectral ranges are 0.25--330~$\mu$m for many cases where possible. For cases with no pressure-broadening data, we use collision theory to bridge the gap. We also probe the effect of absorption cross-sections calculated from different line lists in the context of Ultra-Hot Jupiter and M-dwarf atmospheres. Using 1-D self-consistent radiative-convective thermochemical equilibrium models, we report significant variations in the theoretical spectra and thermal profiles of substellar atmospheres. With a 2000 K representative Ultra-Hot Jupiter, we report variations of up to 320 and 80 ppm in transmission and thermal emission spectra, respectively. For a 3000 K M-dwarf, we find differences of up to 125$\%$ in the spectra. We find that the most significant differences arise due to the choice of TiO line-lists, primarily below 1$\mu$m. In sum, we present (1) a database of pre-computed molecular absorption cross-sections, and (2) quantify biases that arise when characterizing substellar/exoplanet atmospheres due to line list differences, therefore highlighting the importance of correct and complete opacities for eventual applications to high precision spectroscopy and photometry., Comment: accepted in ApJS. 44 pages, 17 figures, 7 tables. Comments are welcome

Total sulfur concentrations in vinegars were determined using molecular absorption of carbon monosulfide (CS) determined with a high-resolution continuum source flame atomic absorption spectrometer. The molecular absorption of CS was measured at 258.056 nm in an air–acetylene flame. Due to non-spectral interference, as well as the different sensitivities to some sulfur compounds, all sulfur species were oxidized to sulfate using a HNO 3 and H 2 O 2 mixture and the analyte addition technique was applied for quantification. The limit of detection (LOD) and limit of quantification (LOQ) were 11.6 and 38.6 mg L −1 , respectively. The concentrations of sulfur in various vinegars ranged from ⩽LOD to 163.6 mg L −1 .

This article describes how to construct a simple, inexpensive, and flexible UV-photometer using one LED (355 nm) as the light source and another (355 nm) as the detector, one resistor, some wiring, a few Lego bricks, and a millivolt meter. The photometer is used to explore several aspects of molecular absorption spectrometry. As practical applications, the amounts of folic acid in folic acid tablets and cinnamaldehyde in cinnamon were found. The results were in accordance with those obtained using a commercial spectrophotometer.

Purpose – The purpose of this paper is to check the actual life of lubricating oil. Design/methodology/approach – Present work aims to find the remaining useful life of the lubricant based on study of periodic deterioration of oil. Chronological samples of oil were selected from the dumper of a local open cast mine. The deterioration in oil was studied using Fourier transform infrared (FTIR) spectroscopy. Findings – The data obtained from FTIR spectroscopy was used in vector projection approach and analytical hierarchy process to evaluate the remaining useful life of the lubricating oil. Originality/value – FTIR spectra were used to study the periodic deterioration of oil. IR radiation with all frequencies in the range was passed through the sample. Radiations at certain frequency, depending upon the molecular structure of compounds in the sample were absorbed and rest was transmitted by the sample. A spectrum representing molecular absorption or transmission was obtained. Transmission spectra have been used in the study. Comparing the percent value of transmission peak of different chronological sample with that of fresh oil was used to represent the periodic degradation in oil.

The therapeutic benefits of extracts obtained from different red grape fractions were thoroughly studied, however, data regarding the comparison of phytochemical extracts prepared from the same varieties coming from organic versus conventional management systems are rather lacking. The present study aimed at comparing some of the phytochemical characteristics and antimicrobial activity of hydroalcoholic (50% v/v) extracts obtained from four varieties of red grapes cultivated respectively in organic and conventional vineyards. Total flavonoid content, total phenolic compounds, and antioxidant activity were determined by molecular absorption spectroscopy. Antimicrobial activity of the studied extracts was evaluated against common bacterial strains isolated from different habitats according to specific lab procedures. The analyses were performed in solid broths by applying the disk diffusion method, which allowed for the simultaneous determination of the spectrum of the sensitivity of the tested bacteria as well as the values of the minimum inhibition concentration (MIC). It was found that favorable antagonistic activities against the tested bacteria strains were exhibited by the hydroalcoholic extracts from the seeds of the organic varieties, respectively the skin of the conventional varieties. Performan¸tă ¸si excelen¸tă în cercetarea multidisciplinară (PerExcel) | Ref. CNFIS-FDI-0397

Non-rocky sub-Jovian exoplanets in high-irradiation environments are rare. LTT 9779b, also known as Transiting Exoplanet Survey Satellite (TESS) object of interest (TOI) 193.01, is one of the few such planets discovered to date, and the first example of an ultrahot Neptune. The planet’s bulk density indicates that it has a substantial atmosphere, so to investigate its atmospheric composition and shed further light on its origin, we obtained Spitzer InfraRed Array Camera secondary eclipse observations of LTT 9779b at 3.6 and 4.5 μm. We combined the Spitzer observations with a measurement of the secondary eclipse in the TESS bandpass. The resulting secondary eclipse spectrum strongly prefers a model that includes CO absorption over a blackbody spectrum, incidentally making LTT 9779b the first TESS exoplanet (and the first ultrahot Neptune) with evidence of a spectral feature in its atmosphere. We did not find evidence of a thermal inversion, at odds with expectations based on the atmospheres of similarly irradiated hot Jupiters. We also report a nominal dayside brightness temperature of 2305 ± 141 K (based on the 3.6 μm secondary eclipse measurement), and we constrained the planet’s orbital eccentricity to e

Carbon-bearing molecules, particularly CO, have been widely used as tracers of molecular gas in the interstellar medium (ISM). In this work, we aim to study the properties of molecules in diffuse, cold environments, where CO tends to be under-abundant and/or sub-thermally excited. We performed one of the most sensitive (down to $\mathrm{��_{rms}^{CO} \sim 0.002}$ and $\mathrm{��_{rms}^{HCO^+} \sim 0.0008}$) sub-millimeter molecular absorption line observations towards 13 continuum sources with the ALMA. CO absorption was detected in diffuse ISM down to $\mathrm{A_v< 0.32\,mag}$ and \hcop was down to $\mathrm{A_v < 0.2\,mag}$, where atomic gas and dark molecular gas (DMG) starts to dominate. Multiple transitions measured in absorption toward 3C454.3 allow for a direct determination of excitation temperatures $\mathrm{T_{ex}}$ of 4.1\,K and 2.7\,K, for CO and for \hcop, respectively, which are close to the cosmic microwave background (CMB) and provide explanation for their being undercounted in emission surveys. A stronger linear correlation was found between $\mathrm{N_{HCO^+}}$ and $\mathrm{N_{H_2}}$ (Pearson correlation coefficient P $\sim$ 0.93) than that of $\mathrm{N_{CO}}$ and $\mathrm{N_{H_2}}$ (P $\sim$ 0.33), suggesting \hcop\ being a better tracer of H$_2$ than CO in diffuse gas. The derived CO-to-\h2 conversion factor (the CO X-factor) of (14 $\pm$ 3) $\times$ 10$^{20}$ cm$^{-2}$ (K \kms)$^{-1}$ is approximately 6 times larger than the average value found in the Milky Way.

The interpretation of nanoplasmonic effects on molecular properties, such as metal-enhanced absorption or fluorescence, typically assumes a fully coherent picture (in the quantum-mechanical sense) of the phenomena. Yet, there may be conditions where the coherent picture breaks down, and decoherence effect should be accounted for. Using a state-of-the-art multiscale model approach able to include environment-induced dephasing, here we show that metal nanoparticle effects on the light absorption by a nearby molecule is strongly affected (even qualitatively, i.e., suppression vs enhancement) by molecular electronic decoherence. The present work shows that decoherence can be thought as a further design element of molecular nanoplasmonic systems., Final Accepted Version

This paper derives a simplified polynomial molecular absorption loss model for 200—450 GHz band. This band has a high potential for near future short range, high data rate applications due to large spectral resources and reasonable path loss. The frequencies around 300 GHz are among the first ones where the molecular absorption loss becomes a significant factor. This loss increases exponentially with the distance and is not a major issue at short distances (few meters), but entirely blocks signals over large distances. Modeling of the molecular absorption loss is relatively straightforward, but requires large numbers of parameters from spectroscopic databases. This paper derives a simplified polynomial absorption loss model for the major absorption lines. This extends and gives more accurate absorption loss values in comparison to the existing ITU-R absorption loss models. The simplified polynomial expressions by ITU-R are mostly limited to about 350 GHz frequency, although being rather accurate up to about 400 GHz. This paper gives a simpler and more accurate absorption loss model to those bands. A part of the considered band, 275—450 GHz band, is subject to World Radiocommunication Conference 2019 (WRC-19) for allocation and operational characterization for the future communication applications.

The tremendous progress in nanotechnology over the last century, makes it possible to engineer tiny nanodevices, which they need a nano-communication network to interact. Two solutions are proposed in literature to create a nano-communication system, either by using the classical electromagnetic paradigm with Terahertz band, or using the bio-inspired molecular communication. However, Terahertz is suffering from molecular absorption and scattering losses at nano level, and the achievable throughput of molecular communication is very low. In this paper, we propose a new solution to establish a wired nano-communication. Self-assembled actin-based is a new method that takes advantage of actin filaments self-assembly to create a nano wire between a transmitter and a receiver, and use electrons as information carriers. VPython framework is used in this paper to perform stochastic simulations of the nano wire formation. The algorithms used for the simulations are presented. The stability of the constructed nano wire is analyzed, and the error probability is calculated. Self-assembled actin-based method promises a fast and stable nano-communication system with a very high achievable throughput.

The ground-state classical path approximation is utilized to compute molecular absorption spectra in a mixed quantum-classical frame. To improve the description for high-frequency vibrational satellites, related quantum correction factors are introduced. The improved method is demonstrated for the Q(y),and Q(x)-bands of pheophorbide a. (C) 2015 Elsevier B.V. All rights reserved.

本文主要阐述了气相分子吸收光谱法测定硫化物时对其校准曲线斜率、截距参考值的分析。通过收集实验室近三年采用气相分子吸收光谱法测定硫化物时制作校准曲线的一系列原始数据，并用数理统计方法对校准曲线及其有关指标进行了详细讨论，得出气相分子吸收光谱法测定硫化物校准曲线的斜率参考值范围为：0.0961 ± 0.0013，截距参考值范围：−0.0018 ± 0.0030。此结果对实验室分析人员判定硫化物项目校准曲线制作是否合格具有一定的参考价值。 This paper mainly analyzed the reference value of the slope rate and intercept from the sulfide’s calibration curve by using gas-phase molecular absorption spectrometry. The calibration curve and its related indexes were discussed in detail by using mathematical statistics method through nearly three-year original data in laboratories. Results showed that the reference range of slope of the gas-phase molecular absorption spectrometry calibration curve is 0.0961 ± 0.0013, and that of intercept is −0.0018 ± 0.0030. These results provide reference for determining eligibility criteria of sulfide calibration curve.

Metal-organic frameworks (MOFs), an emerging type of porous crystalline materials, have received increasing attention in recent years due to their compositional, structural and chemical versatility. Moreover, great progress has been made in the fundamental study and technological development of two-dimensional (2D) materials, such as graphene and metal dichalcogenide nanosheets, which exhibit a number of unique and attractive properties for wide applications. Recently, the smart integration of the aforementioned two types of functional materials, i.e. MOFs and 2D materials, has led to improved performance in molecular absorption, separation and storage, and shown promise in selective catalysis and biosensing. This feature article aims at providing a brief introduction to the composites composed of MOFs and 2D materials, focusing mainly on their preparation methods and applications. Finally, technical challenges and future opportunities in this field will also be discussed.

Detection and characterization of fluoride is an important part of understanding the benefits as well as the potential toxicity of fluoride in biotic and abiotic natural sources. Fluoride can have a detrimental effect on human health at high concentrations (>1.5 mg L−1), thus, it must be detected and quantitated. For this analytical methods play an important role. This review underlines the role of analytical methods in the detection and quantitation of fluoride. The review highlights a variety of analytical methods, for instance, inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectrometry (AAS) and molecular absorption spectrometry (MAS), and electrochemical methods that have been applied in the determination of fluoride. The principles of these techniques in conjunction with their pros and cons, and their applications regarding the determination and detection of fluoride are discussed. The commonly used fluoride sensing methods, including fluorescence and colorimetric methods have also been discussed. We hope this review will promote the next generation approaches and application of innovative analytical methods for fluoride detection and quantification.

Curating the data underlying quantitative structure-activity relationship models is a never-ending struggle. Some curation can now be automated but much cannot, especially where data as complex as those pertaining to molecular absorption, distribution, metabolism, excretion, and toxicity are concerned (vide infra). The authors discuss some particularly challenging problem areas in terms of specific examples involving experimental context, incompleteness of data, confusion of units, problematic nomenclature, tautomerism, and misapplication of automated structure recognition tools.