Miracle-dz/UniFAR-FTUs huggingface dataset:
Mesoporous silicas functionalized with a high density of carboxylate groups as efficient absorbents for the removal of basic dyestuffs

A novel silane bearing a reactive anhydride group was synthesized. Due to its special structure, the direct co-condensation of this synthesized functional silane with TEOS in the presence of different surfactant templates led to ordered mesoporous silicas with different pore sizes and a high density of carboxylic acid groups, which were used as adsorbents for the removal of three basic dyestuffs (methylene blue, phenosafranine and night blue) from waste water. The performed measurements showed that, probably due to their high surface area, good affinity of carboxylic groups and large number of binding sites, the obtained mesoporous materials exhibit a high adsorption capacity and an extremely rapid adsorption rate. Furthermore, these carboxylic-functionalized adsorbents can be regenerated by simple washing with acid solution to recover both the adsorbents and the adsorbed dyes. The experimental data for the adsorption of all three basic dyes were analyzed using Langmuir and Redlich–Peterson isotherm models. It is found that the Langmuir equation provides an accurate description of these adsorption data, suggesting that monolayer adsorption occurred in all cases of the performed sorption processes. In this work, the influences of the pH values of the treated solutions and the pore sizes of the prepared adsorbents on the adsorption behavior were also discussed.
Variation of the Chemical Composition of Essential Oil of Mentha piperita L. during the Growing Time

Abstract This study was conducted over a period of three years. A marked inversion of the menthol/menthone ratio was observed according to harvesting time. The late blooming period gave oils rich in menthol. A second harvest gave a high-quality oil and increased overall yield. Pre-drying did not affect the chemical composition of the oil obtained but allowed larger amounts of plant material to be distilled.
SIMULATING SOIL WATER FLOW WITH ROOT-WATER-UPTAKE APPLYING AN INVERSE METHOD

Modeling soil water flow and distribution in soil-plant systems is challenging because it is difficult and time-consuming to measure and determine the transient root distributions accurately. In this study, an inverse method by Zuo and Zhang (2002), which was utilized to estimate average root-water-uptake rate distributions using two measured soil water content profiles, was applied to simulate soil water flow in a soil-wheat system. A field experiment was conducted to measure distributions of soil water content, soil-plant osmotic potential, and root length density of winter wheat (Triticum aestivum L. cv. Nongda 186). The experiment was performed using clean water and reclaimed wastewater for irrigation. Considering uncertainties of hydraulic parameters and measured soil water content, we conducted a detailed sensitivity analysis of the inverse method. Based on the field experimental data and the inverse method, distributions of normalized root length density (Lnrd) were estimated, thereby simulating soil water flow in the soil-wheat system with water and salinity stresses. The estimated Lnrd and the simulated soil water content profiles compared well with the measured values. The results show that the inverse method was useful for estimating Lnrd distributions and simulating soil water flow with root-water-uptake continuously and effectively in field settings without requiring any measured root density data.
Aromatic iodination: a new investigation on the nature of the mechanism

Following a suggestion by the late Lennart Eberson, we have employed the ICl–HFP (HFP being hexafluoropropan-2-ol) system in iodination reactions, and found unambiguous evidence for the occurrence of an ET-mechanism of halogenation. The evidence is based on the use of ‘intelligent’ substrates, which make it possible to fix the boundaries between the occurrence of an ET-mechanism and of a conventional polar mechanism. In an ‘intelligent’ substrate, in fact, the nature of the product(s) changes significantly depending on the operating mechanism. The ICl–HFP combination is instrumental to the onset of a one-electron oxidation with electron-rich substrates, followed by halogenation. The most prominent example is that of the electron-rich substrate durene (1,2,4,5-tetramethylbenzene, DUR), when compared to mesitylene (1,3,5-trimethylbenzene, MES): with a ‘conventional’ iodination system (i.e., I2/Ag+) and in common solvents, where the polar mechanism holds, durene is less reactive (kMES/kDUR = 46 ± 3), but becomes more reactive (kMES/kDUR = 0.23) in HFP with ICl, where the ET-mechanism takes over. Other substrates also support the onset of ET-pathways in HFP. Finally, a preliminary survey of a biohalogenation reaction induced by laccase indicates the modest occurrence of a polar process of iodination with a few substrates.
Collection Efficiency of Rectangular Slit-Nozzle Inertial Impactors with Impaction Plates of Elliptical Concave Curvature

In this study, the impaction plate with an elliptical concave groove was employed in an effort to enhance the collection efficiency of the slit-nozzle inertial impactor. The major axis length (A) and the minor axis length (B) of the elliptical concave curvature were varied. The effect of the ratio of A to B on the collection efficiency of slit-nozzle inertial impactors was investigated both numerically and experimentally. The numerical results were in good agreement with the experimental data for different values of A/B ratio. The elliptical concave impaction plates were useful in not only reducing the particle bounce but also lowering the cut-off size. The optimum range of the A/B ratio was found to exist for minimizing the cut-off size. When the elliptical concave impaction plates with the A/B ratio of 2 were used for the slit-nozzle inertial impactors, the square-root of the Stokes number was estimated to be lowered from 0.77 to approximately 0.6, resulting in the decrease of the cut-off size by 22% compared with the typical flat impaction plates. Copyright 2013 American Association for Aerosol Research
Elastic properties of crystal surfaces

"Actually the destruction of superconductivity by a current takes place in some finite region of the value of I near I,,and is due to the appearance of the resistive state, i.e., to the gradual restoration of the normal resistance. This process can not be described within the simple Ginzberg-Landau thermodynamic theory. "Relation (1 1) can be obtained also directly from (7) and (8) by using the explicit solutions1' for the potentials A (r) and A,(r). The corresponding calculation is given in the Appendix. "It can be shown that at this point f j > 0, i.e., we have an inflection point. Since it is clear that the inflection point must be located at f> 0, where f-@,(Ho, I) Qn(H0. I) [see (9)], it follows that this point is obviously in the region of metastability of the superconducting state. It can be verified that it is necessary in this case to put c, > 0 in (9).
Impacts of chemical reactivity on ice nucleation of kaolinite particles: A case study of levoglucosan and sulfuric acid

Changes in the ice nucleation properties of mineral dust particles due to soluble coatings are still not well understood. Here we show that the reactivity with soluble materials deposited on the surfaces of kaolinite particles is an important factor affecting the ice nucleation properties of the particles. Using kaolinite particles treated with levoglucosan or H2SO4(i.e., non‐reactive and reactive materials, respectively), we investigated the fraction of particles capable of nucleating ice at temperatures ranging from −34°C to −26°C. Below water saturation, both the levoglucosan and H2SO4 coatings similarly reduced the ice nucleating ability of kaolinite particles. Above water saturation, however, only the H2SO4coatings reduced the ice nucleating ability of the particles, particularly at warmer temperatures. We suggest that the absence or presence of surface chemical reactions plays an important role in determining the number concentrations of ice crystals formed from mineral dust ice nuclei under mixed‐phase cloud conditions.
Crystal and molecular structure of [Cd10(SCH2CH2OH)16](ClO4)4•8H2O. Correlations with 113Cd NMR spectra of the solid and implications for cadmium-thiolate ligation in proteins

/sup 113/Cd NMR chemical shifts in the solid state are reported for (Cd/sub 10/(SCH/sub 2/CH/sub 2/OH)/sub 16/)(SO/sub 4/)/sub 2/. 4H/sub 2/O and (Cd/sub 10/(SCH/sub 2/CH/sub 2/OH)/sub 16/)(ClO/sub 4/)/sub 4/. 8H/sub 2/O. The crystal structure of the latter salt has also been solved and is reported here in greater detail than was previously available for the sulfate salt.
Myrtle berry seed aqueous extract inhibits human neutrophil myeloperoxidase in vitro and attenuates acetic acid-induced ulcerative colitis in rats

We aimed in the present study to investigate the protective effect of a myrtle (Myrtus communis L.) berry seed aqueous extract (MBSAE) on acetic acid (AA)-induced colitis in rats as well as the mechanism implicated in this coli-protection. The use of the LC/MS technique allowed us to identify 18 phenolic compounds in the MBSAE. Secondly, we found that the MBSAE inhibited the luminol-amplified chemiluminescence of resting neutrophils and N-formyl-methionylleucyl-phenylalanine (fMLF) or phorbolmyristate acetate (PMA) stimulated neutrophils in a dose-dependent manner. The MBSAE had no effect on superoxide anions, but it inhibited H2O2 production in the cell free system stimulated with horseradish peroxidase (HRPO) and MPO release from the neutrophils. In vivo, the pre-treatment of rats with sulfasalazine (100 mg kg−1) and the MBSAE (25, 50, and 100 mg kg−1) significantly reduced AA-induced colonic mucosa lesions as well as histopathological changes. The MBSAE counteracted AA-induced lipid peroxidation and the depletion of the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). We also found that the myrtle extract inhibited the increase of the plasma scavenging activity (PSA) and preserved the content of non-enzymatic antioxidants such as sulfhydryl groups (–SH) and reduced glutathione (GSH). More importantly, acetic acid administration increased colonic hydrogen peroxide (H2O2), free iron and calcium levels, while the MBSAE pre-treatment reversed all intracellular mediator perturbations. In conclusion, our data suggests that the MBSAE exerted a potential protective effect against AA-induced injury and oxidative stress in the rat colon. This coli-protection might be related in part to its antioxidant and ROS scavenging activities or by negatively regulating Fenton reaction components such as H2O2 and free iron, which are known to lead to cytotoxicity mediated by intracellular calcium deregulation.
Sinterability of Agglomerated Powders

Powdered compacts that do not have periodic, particulate arrangements exhibit nonperiodic density variations and are, by definition, agglomerated. The void phase in the compact can be separated into pores. The pore coordination number distribution and the critical coordinated number (R c ) governs the volume fraction of pores that can spontaneously disappear by diffusion, and therefore, the compact's sinterability . The pore coordination number distribution is favorably influenced by increasing the compact's initial density and decreasing the size of the multiple particle packing unit (for example, agglomerate size). During heating the pore coordination number distribution is unfavorably shifted by local sintering, which is produced by the spontaneous disappearance of pores with favorable coordination numbers (R c ). Local densification produces a dense, polycrystalline skefetal network. Grain growth during densification, supported by dense regions, favorably alters the coordination number of pores within the skeletal network and improves sinterability. The configuration and microstructure of the dense, skeletal network will control its compliance to deformation by either effective or applied ( hot pressing ) compressive stresses. Deformation of the dense, skeletal network will improve the coordination number distribution and thus sinterability. From this thinking, one concludes that the ideal situation requires either a periodic particle arrangement (which requires monodispersed powders), or lacking this arrangement, alterations in surface chemistry (or structure) such that R c → ∞.
CpG Adjuvant in Allergen-Specific Immunotherapy: Finding the Sweet Spot for the Induction of Immune Tolerance

Prevalence and incidence of IgE-mediated allergic diseases have increased over the past years in developed and developing countries. Allergen-specific immunotherapy (AIT) is currently the only curative treatment available for allergic diseases that has long-term efficacy. Although AIT has been proven successful as an immunomodulatory therapy since its beginnings, it still faces several unmet needs and challenges today. For instance, some patients can experience severe side effects, others are non-responders, and prolonged treatment schedules can lead to lack of patient adherence and therapy discontinuation. A common strategy to improve AIT relies on the use of adjuvants and immune modulators to boost its effects and improve its safety. Among the adjuvants tested for their clinical efficacy, CpG oligodeoxynucleotide (CpG-ODN) was investigated with limited success and without reaching phase III trials for clinical allergy treatment. However, recently discovered immune tolerance-promoting properties of CpG-ODN place this adjuvant again in a prominent position as an immune modulator for the treatment of allergic diseases. Indeed, it has been shown that the CpG-ODN dose and concentration are crucial in promoting immune regulation through the recruitment of pDCs. While low doses induce an inflammatory response, high doses of CpG-ODN trigger a tolerogenic response that can reverse a pre-established allergic milieu. Consistently, CpG-ODN has also been found to stimulate IL-10 producing B cells, so-called B regulatory cells (Bregs). Accordingly, CpG-ODN has shown its capacity to prevent and revert allergic reactions in several animal models showing its potential as both preventive and active treatment for IgE-mediated allergy. In this review, we describe how CpG-ODN-based therapies for allergic diseases, despite having shown limited success in the past, can still be exploited further as an adjuvant or immune modulator in the context of AIT and deserves additional attention. Here, we discuss the past and current knowledge, which highlights CpG-ODN as a potential adjuvant to be reevaluated for the enhancement of AIT when used in appropriate conditions and formulations.
On the Determination of the Hold-Up Time in Reversed Phase Liquid Chromatography

Abstract The determination of the hold-up time in reversed phase liquid chromatography has been studied extensively for the mobile phase system methanol-water. Hold-up times obtained by static methods, linearization of homologous series and so-called “unretained compounds” are discussed and mutually compared. Several n-alkyldimethylsilyl bonded phases have been used for this investigation. A rough estimate of the hold-up time can be obtained by using components of the mobile phase or highly concentrated salt solutions, but only for mobile phase compositions around 60% (v/v) methanol. Hold-up times accurate to 1% can be obtained over the complete range of mobile phase compositions from the linearization of net retention times of homologous series.
The effect of MFI zeolite lamellar and related mesostructures on toluene disproportionation and alkylation

The effect of MFI zeolite nanosheet morphology and related mesostructures on the accessibility of acid sites evaluated from FTIR spectra of different adsorbed probe molecules and conversions and selectivities in toluene disproportionation and alkylation with isopropyl alcohol was investigated. Two-dimensional MFI lamellar zeolite (1.5 nm thickness of layers) and related mesoporous sponge morphologies, most probably with 10-ring channel system not yet structurally fully determined, were synthesized and characterized by XRD, SEM, TEM, and adsorption measurements. FTIR spectroscopy using pyridine, deuterated acetonitrile and 2,6-di-tert-butyl pyridine evidenced high concentrations of accessible Lewis acid sites at the expense of Bronsted acid sites. Ordered mesoporous zeolites exhibited slightly higher toluene conversion in its alkylation with isopropyl alcohol than lamellar MFI or conventional MFI due to easy access to active sites. The lamellar zeolite consisting of less than a unit cell layer was slightly more active than MFI but still exhibited high selectivity to p-cymene. It evidences that alkylation of toluene with isopropyl alcohol proceeds mainly in the 10-ring channel system of MFI zeolite, although the effect of large external surface cannot be neglected. Increased para-selectivity compared with thermodynamic value is achieved even in the case of extremely thin zeolite nanosheets.
Factors Influencing Participation in COVID-19 Clinical Trials: A Multi-National Study

In 2020, the World Health Organization has characterized COVID-19, a disease caused by infection with the SARS-CoV-2 virus, as a pandemic. Although a few vaccines and drugs have been approved to, respectively, prevent or treat the disease, several clinical trials are still ongoing to test new vaccines or drugs to mitigate the burden of the pandemic. Few studies have shown the role of host genetics in disease prognosis and drug response highlighting the importance of diverse participation in COVID-19 clinical trials. The goal of this study is to assess public attitudes in Egypt, Saudi Arabia, and Jordan toward participating in COVID-19 clinical trials and to identify the factors that may influence their attitude. An online questionnaire was developed and distributed among the target group through social media platforms. The number of responses was 1,576. Three quarters (74.9%) of participants heard about clinical trials before, 57.6% of them had a positive attitude toward participation in COVID-19 clinical trials. The conduct of clinical trials in accordance with the scientific, research, and ethical guidelines was a strong predictor of willingness to participate in clinical trials. Other positive factors also included protection of family from COVID-19 and contributing to the return to normal community life as well as receiving additional healthcare benefit was the fourth significant predictor. On the other hand, the thought that clinical trials can have a negative impact on the health of participants strongly predicted the unwillingness of individuals to participate in such trials. This was followed by having limited information about the novel coronavirus and COVID-19 and the lack of trust in physicians and hospitals. In general, Arab citizens are accepting the concept and have a positive attitude toward COVID-19 clinical trials. Increasing awareness of COVID-19 and clinical trials, enforcing the concept of altruism, and placing clear policies in conducting clinical trials are needed to increase participation in clinical trials among Arabs.
Mass spectrometric evidence for icosahedral structure in large rare gas clusters: Ar, Kr, Xe

Clusters of argon, krypton, and xenon are grown in a free jet and ionized by electron impact. The size of these clusters, (Rg)+n, extends up to n≂1000. Individual cluster sizes are mass resolved up to n≂570 in the case of Ar+n. The well known, but puzzling differences in the size distributions of Kr and Xe clusters disappear beyond n≂130, while those between Ar and Xe disappear beyond n≂220. The most pronounced ‘‘magic numbers’’ in the distributions of large cluster ions occur at n=147 (148 for Ar), 309, and 561, in striking agreement with the number of atoms required to build icosahedral clusters with 3, 4, and 5 complete coordination shells, respectively. Closure of the 6th icosahedral coordination shell is indicated by another strong intensity drop at n≂923 in the unresolved part of the spectra. Several additional intensity extrema are observed between major shell closures. A simple structural model, assuming an icosahedral core decorated by the additional atoms, accounts for these anomalies reasonably.
Rate constants of the reactions of metastable N2(A 3Σ+u) in v=0, 1, 2, and 3 with ground state O2 and O

Overall rate constants for the removal of N2(A,v) by O2 and O were measured at 298 K in a rapidly pumped flow reactor using laser‐induced fluorescence (LIF) detection of N2(A,v) by excitation in the first positive system of N2, B(3πg)←A(3Σ+u). O atoms were generated in microwave discharges of pure O2 prepared by thermal decomposition of KMnO4. Measured rate constants for N2(A,v)+O2 increased from 2.5×10−12(v=0) to 5.7×10−12 cm3 s−1(v=3). For N2(A,v)+O(3P), they were an order of magnitude larger, rising from 3.5×10−11(v=(0) to 5.2×10−11 cm3 s−1(v=3). They are compared with previous work and discussed in terms of the likely molecular interaction that they represent.
Redetermination of the chromium position in ruby

By JAMESW.MCCAULEY*and G.V. GIBBS**Materials Research Laboratory, The Pennsylvania State UniversityUniversity Park, Pennsylvania(Received 22May 1971)AuszugEine nach der Ausgleichsmethode und auf Grund einer dreidimensionalenSammlung von Intensitaten der Reflexe an einem Rubinkristall mit 5,2Mol-prozent Cr20a durchgefiihrte Verfeinerung zeigt, daB Crstatistisch die Kation-lage der Korundstruktur besetzt, jedoch daraus leicht, urn 0,03A, auf das inder c-Richtung nachste Kation hin verschoben ist.AbstractResults of a least-squares refinement utilizing three-dimensional, single-crystal, x-ray-diffraction, intensity data from aruby with 5.2mole % Cr20ashows that Crisdisordered inthe cation site ofthe corundum structure, but
Alkyl Chain Symmetry Effects in Mixed Cationic–Anionic Surfactant Systems

Abstract We study symmetry effects of hydrophobic tails in mixed oppositely charged surfactant systems. Equal hydrophobicity of the participating surfactants is obtained either (1) by equal hydrocarbon surfactants chain length or (2) by unequal surfactants chain length when one chain is perfluorinated. Three systems were studied: symmetric system of type (1) or (2), and an asymmetric system. Some unusual structural changes are observed in a hydrocarbon–fluorocarbon mixed single-chain oppositely charged surfactant system in the dilute region. Both the cationic hydrocarbon surfactant, dodecytrimethylammoniumchloride (DoTAC), and the anionic fluorocarbon surfactant, sodium perfluorononanoate (SPFN), are separately soluble in water, forming micellar solutions at high water concentration followed by the formation of liquid crystal phases at low water content. Upon mixing the two surfactants in an equimolar ratio at low total surfactant concentration (C
Synthesis and Characterization of Poly(vinylpyrrolidone)-Modified Zinc Oxide Nanoparticles

We have synthesized highly monodisperse wurtzite ZnO nanoparticles using poly(vinylpyrrolidone) (PVP) as the capping molecules. The effect of surface modification on the size, structure, morphology, and optical properties of ZnO nanoparticles was investigated. It was found that many properties of the ZnO nanoparticles could be optimized by simply varying the molar ratio Zn(II)/PVP. The ZnO nanoparticles prepared under the optimum conditions are particularly stable, monodisperse, as well as small in size. The EXAFS result showed a structural contraction in the ZnO nanoparticles relative to the bulk. These nanoparticles exhibit distinct excitonic absorption features, markedly enhanced near-band-edge UV photoluminescence, and significantly reduced defect-induced green emission. The third-order nonlinear optical response of these PVP-capped ZnO nanoparticles in a dilute solution was found to be larger than that of the bulk ZnO by at least 2 orders of magnitude.