Miracle-dz/UniFAR-FTUs huggingface dataset:
Limitations of current LP-WAN systems

— LP-WAN systems are important components of the IoT. They allow the exchange of small amount of data over long distances with relatively little energy and little infrastructure complexity. These important characteristics have led to great interest. They have also led to legitimate application and market dreams. As is often the case with new technologies, there are misunderstandings that can result in disappointments if the limitations of the technologies are not properly understood. In this work, we highlight some of those restrictions, looking especially (but not only) at aspects such as energy, throughput and determinism. We draw on our own practical experiences and measurements, as well as works done by other groups.
Simultaneous dry and ambient measurements of aerosol size distributions at the Jungfraujoch

In a field campaign at the high-alpine site Jungfraujoch (JFJ, 3580 m asl), in-situ aerosol size distributions were measured simultaneously outdoor at ambient conditions (temperature T < −5 °C) and indoor at dry conditions (T ≈ 25 °C and relative humidity RH < 10%) by means of two scanning mobility particle sizers (SMPS). In addition, measurements of hygroscopic growth factors were performed with a hygroscopicity tandem differential mobility analyzer (H-TDMA). The measured growth factors, being a monotonic function of the relative humidity (RH), were fitted with a modified Köhler model. A comparison between dry and ambient size distributions shows two main features: First, the dry total number concentration is often considerably smaller (on average 28%) than the ambient total number concentration, and is most likely due to the evaporation of volatile material at the higher temperature. These particle losses mainly concern small particles (dry diameter D ≲ 100 nm), and therefore have only a minimal affect on the surface and volume concentrations. A slight correlation between ambient RH and the magnitude of particle loss was observed, but it was not possible to establish an empirical model for a quantification. Second, the dry number size distribution is shifted towards smaller particles, reflecting the hygroscopic behavior of the aerosols. To link the ambient and the dry size distributions we modeled this shift using the H-TDMA measurements and a modified Köhler model. The corrected dry surface and volume concentrations are in good agreement with the ambient measurements for the whole RH range, but the correction works best for RH < 80%. The results indicate that size distribution data measured at indoor conditions (i.e. dry and warm) may be successfully corrected to reflect ambient conditions, which are relevant for determining the impact of aerosol on climate.
Characterisation of Refractory Wastes at Heavy Oil-Contaminated Sites: A Review of Conventional and Novel Analytical Methods

Methods for the analysis of petroleum hydrocarbons in contaminated soil and water are subject to a range of constraints arising from the complexity of waste-soil-groundwater matrices, the inherent chemical diversity of the spilled product and the requirements of the site investigation. The analytical uncertainties associated with refractory weathered contaminants, which exist as pockets of residual saturation in the contaminated subsurface are a major problem. Adoption of a transparent, phased approach to waste characterisation significantly mitigates these constraints and improves the use of site investigation resources. Moreover, the use of biomarker monitoring and gas chromatography-stable carbon isotope ratio mass spectrometry within such a scheme is likely to be of significant benefit to remediation experts in the elucidation of waste source terms and the selection and monitoring of remedial treatment technologies.
The near infrared spectrum of solid silane

The infrared absorption spectrum of solid SiH4 has been measured between 4000 and 10500 cm−1 in both phases I and II. Eighteen new overtone and combination bands have been observed and assigned. Some of them correspond to sets of propagating vibrons, others to localized overtones with strong anharmonicities. The observations of the overtones (n−1)ν1+ν3 (n=2,3,4,5) are in excellent agreement with a local mode approach, usually applied to the vibrations of isolated molecules. Its use provides a determination of both the harmonic and anharmonic parameters of the SiH4 stretching in the solid phase.
Hydrolysis, adsorption, and dynamics of silane coupling agents on silica surfaces

The hydrolysis of alkoxysilane coupling agents has been followed using proton NMR. The disappearance of the silane ester and the appearance of the alkoxy group were observed to follow pseudo-first-order kinetics. The apparent rate constant was found to be dependent on the concentration of the silane coupling agent and the pH. The adsorption of the coupling agents onto Cab-O-Sil silica was quantified using FT-IR spectroscopy. It was found that monolayer coverage was obtained with about 0.65 mmol/100 m2. Solid-state deuterium NMR was used to probe the behavior of the coupling agent on the silica. The coupling agents adsorbed on the surface from deuterated aminopropyltriethoxysilane (DAPES) and deuterated aminobutyltriethoxysilane (DABES) showed similar motional characteristics. In contrast, the mobility of condensed polymers from DABES was much less restricted than that from DAPES. The amount of hydrolysis in acetone-water mixtures increased the amount of surface-adsorbed material and lessened surface mobil.
A Test of the Suitability of CCD Area Detectors for Accurate Electron-Density Studies

The performance of the Siemens SMART CCD (charge-coupled device) area detector has been tested to assess its suitability for accurate electron-density (ED) determination. 92043 diffraction intensities (14701 unique reflections, 65 h experiment) have been collected on a reference crystal of methyl 2-[(4-butyl-2-methyl-6-oxo-5-{4-[2-(1H-tetrazol-5-yl)phenyl]benzyl }-1,2-dihydropyrimidin-1-yl)methyl]-3-thiophenecarboxylate (C30H30N6O3S) at T = 120 K and compared with those (51485, 14699 unique, 600 h) obtained from a previous collection at T = 18 K on the same crystal using a diffractometer equipped with a conventional detector. Results from spherical and multipolar refinements (agreement factors, standard uncertainties of refined variables and geometries after correction for thermal motion) have also been compared. The λ/2 contamination, which affects area detectors but not well tuned conventional detectors, has been carefully investigated and proved to be a negligible source of errors (which can anyway be easily corrected). The encouraging results of this test prove that area detectors are also well suited for charge-density studies, offering a cheap and fast data-collection mode, without loss of accuracy, which can be exploited for ED studies on large systems.
The Catalytic Evaluation of Structured Zeolite Catalysts

ZSM-5 films, with thicknesses between 150 and 2300 nm, supported on 3 mm diameter alumina beads are characterised in terms of their catalytic activity and selectivity for tri-isopropylbenzene cracking and para-xylene isomerisation at 450 °C. A reaction-diffusion model adequately represents the experimental data and is used to estimate intrinsic reactivity and diffusion properties of the zeolite films. Results show that the external activity, overall activity and the diffusivity increase with increasing film thickness. The variation in reactivity and diffusivity, when compared to physio-chemical data, are a result of structural defects and non-homogeneities of the zeolite film. The measured diffusivities are within an order of magnitude of those extrapolated from literature. Thick zeolite films have the largest Thiele modulus as the increase in zeolite film thickness dominates over the structural defects. The largest selectivity improvements are observed for thick zeolite films.
Class balancing in customer segments classification using support vector machine rule extraction and ensemble learning

An objective and data-based market segmentation is a precondition for efficient targeting in direct marketing campaigns. The role of customer segments classification in direct marketing is to predict the segment of most valuable customers who is likely to respond to a campaign based on previous purchasing behavior. A good-performing predictive model can significantly increase revenue, but also, reduce unnecessary marketing campaign costs. As this segment of customers is generally the smallest, most classification methods lead to misclassification of the minor class. To overcome this problem, this paper proposes a class balancing approach based on Support Vector Machine-Rule Extraction (SVM-RE) and ensemble learning. Additionally, this approach allows for rule extraction, which can describe and explain different customer segments. Using a customer base from a company? s direct marketing campaigns, the proposed approach is compared to other data balancing methods in terms of overall prediction accuracy, recall and precision for the minor class, as well as profitability of the campaign. It was found that the method performs better than other compared class balancing methods in terms of all mentioned criteria. Finally, the results confirm the superiority of the ensemble SVM method as a preprocessor, which effectively balances data in the process of customer segments classification.
Kraft lignin in polyurethanes I. Mechanical properties of polyurethanes from a kraft lignin–polyether triol–polymeric MDI system

Polyurethanes with various NCO/OH ratios and kraft lignin contents were synthesized by polymerization of kraft lignin (free of the low and high molecular weight fractions), a propylene–oxide-based polyether triol and polymeric MDI in tetrahydrofuran solution. Films were made by solvent casting and tested with respect to swelling behavior and tensile properties. The main findings were: At low NCO/OH ratios, kraft lignin contributed effectively to the formation of the three dimensional network; under particular conditions of NCO/OH ratio and kraft lignin content, polyurethanes of considerable toughness were obtained; at high kraft lignin contents, the obtained polyurethanes were hard and brittle regardless of the NCO/OH ratio used.
Extração em Fase Sólida Dispersiva na determinação de resíduos e contaminantes em alimentos

This paper provide an overview of the technique Dispersive Solid Phase Extraction (D-SPE) as an important step of the QuEChERS method that permit to obtain, in a easy and quick procedure, cleaned extracts for the multiresidue analysis. The D-SPE involves, in general, the use of one or more sorbent together with magnesium sulfate anhydrous in a centrifuge tube to remove the co-extractives from the organic extract. This technique is practical and efficient to clean-up extracts from different complex samples, like foods of vegetable or animal origin. Some practical details of different sorbents are presented with principal applications.
Spectral encoding on Gold Nanorods Doped in a Silica Sol–Gel Matrix and Its Application to High‐Density Optical Data Storage

Metallic nanorods exhibit fascinating optical properties due to surface plasmons—collective oscillation of the electron cloud within a particle. They exhibit two principle absorption bands that correspond to surface plasmon resonance (SPR) along the longitudinal and transverse directions of the nanorod. Most importantly, the longitudinal band can be tuned with the aspect ratio of the rod, making it a spectrally tuneable optical material, which can be applied to a variety of devices from bioimaging to high‐density optical storage. Here, spectral encoding for high‐density optical storage applications is demonstrated on two sizes of gold nanorods (aspect ratios of three and five) doped in a silica sol–gel matrix by femtosecond pulsed laser irradiation. It is widely known that high‐power pulsed laser irradiation causes metal nanorods to undergo shape transformations via the process of melting or fragmentation. The process is enhanced if the laser wavelength is tuned at the longitudinal surface plasmon resonance peak of the nanorods, which results in a significant reduction or shift in the surface plasmon resonance peak. As such a shape change occurs only on the subpopulation of rods that have a longitudinal plasmon band matching the laser wavelength, a size‐ or spectrum‐selective shape transition is possible in a rod mixture with varying aspect ratios. The current spectral encoding technology can be incorporated into existing optical disc technology, such as three‐dimensional bit‐by‐bit and holographic, and can increase the capacity limit by utilizing the spectral domain.
Dihydroperimidine-Derived N-Heterocyclic Pincer Carbene Complexes via Double C–H Activation

The reactions of 1,8-diaminonaphthalene with paraformaldehyde and secondary phosphines (HPR2, R = Ph, Cy) directly afford N,N′-bis(phoshinomethyl)dihydroperimidines H2C(NCH2PR2)2C10H6 (R = Ph (1a), Cy (1b)), the methylene group of which undergoes chelate-assisted double C–H activation with [RhCl(PPh3)3] to afford dihydroperimidine-derived N-heterocyclic pincer carbene (per-NHC) complexes [RhCl{═C(NCH2PR2)2C10H6}] (R = Ph (2a), Cy (2b)). Insight into the mechanism of these C–H activation processes is provided by the reaction of 1b with [IrCl(CO)(PPh3)2] to provide the dihydroperimidinyl-hydrido complex [IrHCl(CO){CH(NCH2PR2)2C10H6}] (3b), which in turn reacts with silver salts Ag[Y] to afford, via hydride abstraction and subsequent C–H activation, the per-NHC ligated salts [IrHCl(CO){═C(NCH2PR2)2C10H6}] ([4b]Y, Y = PF6, SbF6, PO2F2).
Electron swarm parameters in pure C2H2 and in C2H2–Ar mixtures and electron collision cross sections for the C2H2 molecule

Electron swarm parameters (the drift velocity and the longitudinal diffusion coefficient) were measured in pure C2H2 and also in C2H2–Ar mixtures containing 0.517% and 5.06% acetylene over wide E/N ranges. These swarm parameters were analysed using a Boltzmann equation analysis and a set of electron collision cross sections for the C2H2 molecule was derived so that it was consistent with the present swarm data and published ionization coefficient. The present result suggested the presence of a Ramsauer–Townsend minimum in the elastic momentum transfer cross section at 0.08 eV and prominent threshold and resonance peaks in the ν4/ν5 vibrational excitation cross section. The present cross section set was also confirmed to be consistent with the published experimental total cross section of C2H2.
Thermal and mechanical properties of anhydride‐cured epoxy resins with different contents of biobased epoxidized soybean oil

Thermosetting resins were synthesized by the partial replacement of the synthetic epoxy prepolymer based on diglycidyl ether of bisphenol A (DGEBA) with increasing amounts of epoxidized soybean oil (ESO) with methyltetrahydrophthalic anhydride as a crosslinking agent and 1-methyl imidazole as an initiator. Calorimetric studies showed a drop in the reaction heat with ESO content; this was associated with the lower reactivity of oxirane rings in ESO due to steric constrains. The effects of the replacement of increasing amounts of synthetic DGEBA with ESO on the network properties, such as the storage modulus (E′) in the glassy and rubbery regions, glass-transition temperature (Tg), and impact and compressive properties were examined. All formulations were transparent, although phase-separated morphologies were evidenced by scanning electron microscopy observations. The intensity of the transmitted light passed to a minimum at a short reaction time associated with the cloud point and then increased continuously until the refractive index of the dispersed phase approximated that of the continuous phase at complete conversion. The combination of DGEBA with 40 wt % ESO resulted in a resin with an optimum set of properties; E′ in the glassy state was 93% of that of the neat DGEBA resin, Tg decreased only about 11°C, and the impact strength increased about 38% without a loss of transparency. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Fabrication of conducting GeSi/Si micro- and nanotubes and helical microcoils

Conducting micro- and nanotubes and free-standing flexible helical microcoils have been fabricated from strained GexSi1-x/Si heterolayers. The fabrication technique was based on self-rolling of a thin highly strained epitaxial GexSi1-x/Si bifilm detached from the substrate by selective etching of a sacrificial layer in a roll-shaped tube. The obtained tube diameters varied from 10 nm to 13 µm, depending on the thickness and lattice mismatch of the GeSi/Si bilayer. GeSi/Si tubes and helical coils, up to 70 nm in diameter, exhibit good conducting properties and high mechanical strength.
PARAMETERS INFLUENCING DRYING BEHAVIOR OF RUBBER WOOD (HEVEA BRAZILLIENSIS) AS DETERMINED FROM DESORPTION EXPERIMENT

ABSTRACT In this study, the drying properties of rubber wood, which are the basic parameters for kiln scheduling design, were determined from desorption experiment. Equilibrium moisture content expression was developed. The diffusion coefficients at different drying environments were evaluated. It is more appropriate to determine the diffusion coefficients by the optimum scheme in comparison to other schemes; the logarithmic, square-root and half-fraction of evaporable moisture schemes. Finally, the diffusion coefficient of rubber wood was described by, instead of wood moisture content, the drying temperature and relative humidity, which are the parameters controlling the drying kiln operation.
Ambient Cured Tartaric Acid Modified Oil Fatty Amide Anticorrosive Coatings

A novel tartaric acid modified fatty amide diol (TAFA) was synthesized through the condensation polymerization of N,N‐bis(2‐hydroxy ethyl) linseed oil fatty amide and tartaric acid (TA). The structural elucidation of the TAFA resin was carried out by FT‐IR,1H‐NMR, and 13C‐NMR spectroscopic techniques. The physico‐mechanical and physico‐chemical characterization of the resin were done by standard methods. TAFA, when further reacted with butylated melamine formaldehyde (BMF) in different phr (part per hundred part of resin) (TAFA‐BMF) was found to cure at room temperature. The TAFA‐BMF cured system was subjected to spectroscopic analysis to ascertain the structure and curing scheme of the same. The thermal studies of these resins were carried out by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The physico‐mechanical properties and anticorrosive performance of TAFA‐BMF coatings were evaluated by standard methods. The effect of TA and BMF on thermal stability, physico‐mechanical and anticorrosive properties of resins was also investigated.
A low-temperature X-ray camera

The paper contains a description of a low-temperature X-ray camera suitable for the examination of small plates. The specimen under examination is cooled in a stream of air for temperatures in the range between room temperature and -170° C, and by dropping liquid air on it for the lowest temperature reached (-194° C). Temperatures were measured directly with a copper-constantan thermocouple for single specimens or by reference to the lattice parameter of a standard material for double specimens. These temperatures were taken whilst the specimens were being simultaneously rotated and oscillated. The results obtained with silver and iron are quoted. The coefficients in the expansion equation at = a0(1 + αt + βt2 + γt3) for these metals were found to be as follows: Silver: α = 18.2606 × 10-6, β = 3.9156 × 10-9, γ = - 17.2794 × 10-12, and a0, the lattice parameter at 0° C, is 4.0760 kx; Iron: α = 11.9784 × 10-6, β = 15.8447 × 10-9, γ = - 3.2973 × 10-12, a0 = 2.8598 kx.
FT-IR Study of UV-Irradiated Stoneground Wood Pulp

The photo-induced colour reversion of handsheets of unbleached and bleached stoneground wood pulp was studied by FT-IR transmission spectroscopy. Changes in the chemical structure of thin handsheets were monitored quantitatively as a function of repeated exposures to UV irradiation at 320 nm followed by storage in the dark. A slight loss of carbohydrate structures was observed throughout the cycles, while a pronounced loss in lignin aromaticity was produced by the UV irradiation.
Pakistani Bell Pepper (Capsicum annum L.): Chemical Compositions and its Antioxidant Activity

A total of 33 compounds of bell pepper volatile oils were identified by gas chromatography and mass spectrometry (GC–MS) in the volatile dichloromethane extract obtained from Pakistani bell pepper (Capsicum annum L.), locally known as Shimla Mirch. The main constituents of the volatile oils of bell pepper (fresh and dried) were benzaldehyde (20.9–3%), 2-methoxy-3-isobutyl-pyrazine (20.4–9%), Z-β-ocimene (13–3%), 4-hydroxy-2,5-dimethyl-3(2H)-furanone (12.7–2.5%), and β-ionone (12.1–0.9%). Non volatile components of bell pepper ‘Twingo’ and Bell Pepper No. 1 (fresh and dried) were extracted with n-hexane and methanol. All extracts from solvent extraction and the volatile extract described above exhibited clear antioxidant activities at levels of 10–60 μg/mL in the 2,2-diphenyl-1-picrylhydrazyl/linoleic acid and β-carotene bleaching assays. The dried bell pepper ‘Twingo’ volatile oil inhibited 2,2-diphenyl-1-picrylhydrazyl activity by 70.95 ± 0.89%, at a concentration of 60 μg/mL. This study indicates that Pakistani bell pepper could be used to produce novel natural antioxidants as well as a flavoring agent in various food products.
Selective Transport of Cu(II) across a Polymer Inclusion Membrane with 1-Alkylimidazole from Nitrate Solutions

The selective transport of copper(II), zinc(II), cobalt(II), and nickel(II) ions from nitrate solutions across polymer inclusion membranes (PIMs), which consist of cellulose triacetate as polymeric support, o-nitrophenyl pentyl ether as plasticizer, and 1-alkylimidazole (alkyl from hexyl- to decyl) as ion carrier was reported. PIM was characterized by using atomic force microscopy (AFM) technique. The results show that Cu(II) can be separated very effectively from other transition metal cations as Zn(II), Co(II), and Ni(II) (at a concentration of 10−3 mol/dm3 each). Alkyl substituents at position 1 of the imidazole ring have been found to affect the hydrophobic properties and initial flux of the transported metal ions. The efficiency of separation of metal ions by 1-alkylimidazole followed the sequence: Cu(II) > Zn(II) > Co(II) > Ni(II). The highest selectivity coefficient for Cu(II) was found with 1-hexylimidazole and its 1 mol/dm3 solution in PIM. Separation of the ions was more effective for the nitrates(V) than for chlorides.