Miracle-dz/UniFAR-FTUs huggingface dataset:
Adsorption of Pollutants from Aqueous Solutions Using Activated and Non-Activated Oak Shells: Parametric and Fractional Factorial Design Study. Part I. Removal of Copper

Non-activated and chemically activated oak shells were evaluated for their ability to remove Cu2+ ions from aqueous solutions. Batch adsorption experiments were conducted to investigate the effect of contact time, sorbent concentration, Cu2+ ion concentration and the pH of the solution on the sorption process. The Cu2+ ion uptake by oak shells increased with decreasing sorbent concentration or with an increase in Cu2+ ion concentration or solution pH. The fractional factorial design technique was applied in order to determine the average Cu2+ ion uptake, the contribution of each operating variable to the value of the uptake and the interaction among the operating variables when the sorbent type, sorbent concentration, Cu2+ ion concentration, pH, contact time and salt were all varied from one level to another. Application of this technique showed that the sorbent concentration had the largest influence on the value of the Cu2+ ion uptake followed by Cu2+ ion concentration and sorbent type. Interaction among the different operating variables played an important role in the adsorption process.
Non-cancer risk assessment from exposure to mercury (Hg), cadmium (Cd), arsenic (As), copper (Cu) and lead (Pb) in boreholes and surface water in Tinga, in the Bole-Bamboi District, Ghana

The study assessed non-cancer human health risk from exposure to mecury (Hg), cadmium (Cd), arsenic (As), copper (Cu), and lead (Pb) in surface and groundwater in Tinga, in the Bole-Bamboi District. A total of 42 water samples were collected for a period of six months. Mean concentration of Hg, Cd, and Pb were found to be (0.050 ± 0.04 mg/L), (0.031 ± 0.02 mg/L) and (0.07 ± 0.05 mg/L), respectively. These were all above the World Health Organization (WHO) recommended guideline values for drinking water. Non-cancer human health risk as a result of exposure to Hg and Cd through ingestion of borehole water was found to be high. Hazard quotients (HQ) as a result of exposure to mercury for adults and children ranged from 2.5 to 30 through central tendency exposure (CTE) and 4.6 to 60 through reasonable maximum exposure (RME). For Cd, CTE ranged from 0.96 to 2.7 and RME ranged from 1.8 to 5.4. The HQ for exposure to Hg and Cd through ingestion of ground water exceeded the acceptable United States Environmental Protection Agency (USEPA) value of 1.0. This implies that resident children and adults are likely to develop diseases (such as low intelligent quotient, tremor, kidney failure, increased hypertension and cardiovascular diseases) associated with long term exposure to Hg and Cd. Key words: Small-scale mining, Tinga, non-cancer, health risk, hazard quotient, borehole, surface water.
Determination of lactulose in foods: a review of recent research

Summary This article mainly discusses the methods for the determination of lactulose. The methods referred to were spectrophotometric methods, high-performance liquid chromatography (HPLC), gas chromatography (GC) and other related techniques (such as: capillary electrophoresis, differential pH methods, flow analysis methods). Spectrophotometric methods are suitable both for qualitative and quantitative determination of lactulose with good efficiency and limited costs. Although tedious and time-consuming preparation of samples is necessary for HPLC and GC methods, both of them afford high resolution and excellent accuracy for lactulose analysis. In addition, other methods (CE, FA and differential pH methods) could also provide reliable results for lactulose determination with relatively simple operation. Various methods of recent research were introduced by analysing the advantages and disadvantages of them.
The effect of humidity on the charge/phase-angle patterns of AC corona pulses in air

AC corona pulses have been measured using a computer-based commercial partial discharge detector. The pulse height distribution was measured in air as a function of phase angle and pulse height for a range of voltages using a point/cup electrode system. An earlier paper discussed the effect of space charge on the onset voltages for both positive and negative half-cycles and on the patterns obtained. In the work reported in this paper, the humidity was varied, and large changes were found in the patterns observed in both half-cycles. At high humidities the negative half-cycle corona largely ceased but a second positive corona onset appeared in the second quarter of the cycle. An explanation for these phenomena is proposed in terms of the effect of the production of negatively charged water molecule clusters. Their production results in a lower effective ionization coefficient and thus higher critical field, and their lower mobility results in a more effective negative space charge. The former reduces the positive space charge in the positive half-cycle thus allowing avalanches and streamers to develop during the second quarter of the cycle. The latter results in a stronger negative space charge during the negative half-cycle which suppresses the corona during that half-cycle.
Multiphase OH oxidation kinetics of organic aerosol: The role of particle phase state and relative humidity

Organic aerosol can exhibit different phase states in response to changes in relative humidity (RH), thereby influencing heterogeneous reaction rates with trace gas species. OH radical uptake by laboratory‐generated levoglucosan and methyl‐nitrocatechol particles, serving as surrogates for biomass burning aerosol, is determined as a function of RH. Increasing RH lowers the viscosity of amorphous levoglucosan aerosol particles enabling enhanced OH uptake. Conversely, OH uptake by methyl‐nitrocatechol aerosol particles is suppressed at higher RH as a result of competitive coadsorption of H2O that occupies reactive sites. This is shown to have substantial impacts on organic aerosol lifetimes with respect to OH oxidation. The results emphasize the importance of organic aerosol phase state to accurately describe the multiphase chemical kinetics and thus chemical aging process in atmospheric models to better represent the evolution of organic aerosol and its role in air quality and climate.
A Novel Nanolithography Technique for Self-Assembled Monolayers Using a Current Sensing Atomic Force Microscope

A nanolithography technique for a self-assembled monolayer (SAM) using a current sensing atomic force microscope (CSAFM) is proposed. Using this method, we prepared nanometer-sized patterns on the octadecanethiol SAM by removing octadecanethiol molecules at a force of a few nanonewtons in toluene when an appropriate positive or negative bias was applied. The relation between the pattern formation and the applied bias was studied at both positive and negative polarizations. The minimum pattern size achieved by this method was 15 nm. The formation probability as a function of the applied force and the trace amount of water contained in toluene was also systematically investigated. These results suggested an electrochemical mechanism for the removal of thiol molecules.
Electrocatalytic Oxidation of Nitrite at Gold Nanoparticle‐ polypyrrole Nanowire Modified Glassy Carbon Electrode

A novel chemically modified electrode based on the dispersion of gold nanoparticles on polypyrrole nanowires has been developed to investigate the oxidation behavior of nitrite using cyclic voltammetry, differential pulse voltammetry and chronoamperometry techniques. The diffusion coefficient (D), electron transfer coefficient (α) and charge transfer rate constant (k) for the oxidation of nitrite were determined. The modified electrode exhibited high electrocatalytic activity toward the oxidation of nitrite. The catalytic peak current was found to be linear with nitrite concentrations in the range of 8.0×10−7−2.5×10−3 mol·L−1 with a detection limit of 1.0×10−7 mol·L−1 (s/n=3). The proposed method was successfully applied to the detection of nitrite in water samples with obtained satisfactory results. Additionally, the sensor also showed excellent sensitivity, anti-interference ability, reproducibility and stability properties.
Hydrogen/Deuterium Exchange Mass Spectrometry for the Study of Methanol-induced Conformational Transitions in Ubiquitin

HYDROGEN/DEUTERIUM EXCHANGE MASS SPECTROMETRY FOR THE STUDY OF METHANOL-INDUCED CONFORMATIONAL TRANSITIONS IN UBIQUITIN In aqueous solutions with high concentrations of methanol at low pH, the global conformation of ubiquitin denatures to a structure of increased helical character at 50% methanol to a highly helical denatured structure at 90% methanol. Circular dichroism analysis and hydrogen/deuterium exchange mass spectrometry experiments have been reported for the monitoring of alcohol-induced conformational transitions of ubiquitin upon exposure to increasing concentrations of methanol. A bottom-up analysis of deuterium labeled ubiquitin was used in this study to examine the local conformational transitions of ubiquitin upon exposure to solutions of varying concentrations of methanol. Analysis of ubiquitin and nine peptide fragments, produced from a ubiquitin-pepsin digest, were monitored through the use of a Varian 500-LCMS ion trap. The bottom-up approach to hydrogen/deuterium exchange mass spectrometry isolated most deuterium exchange to the β-strands of ubiquitin, suggesting the methanol-induced transitions of ubiquitin were highly characterized by the unfolding of the native-state β-sheets.
A Human-Immune-System (HIS) humanized mouse model (DRAGA: HLA-A2. HLA-DR4. Rag1 KO.IL-2Rγc KO. NOD) for COVID-19

We report the first Human Immune System (HIS)-humanized mouse model (“DRAGA”: HLA-A2.HLA-DR4.Rag1KO.IL-2RγcKO.NOD) for COVID-19 research. This mouse is reconstituted with human cord blood-derived, HLA-matched hematopoietic stem cells. It engrafts human epi/endothelial cells expressing the human ACE2 receptor for SARS-CoV-2 and TMPRSS2 serine protease co-localized on lung epithelia. HIS-DRAGA mice sustained SARS-CoV-2 infection, showing deteriorated clinical condition, replicating virus in the lungs, and human-like lung immunopathology including T-cell infiltrates, microthrombi and pulmonary sequelae. Among T-cell infiltrates, lung-resident (CD103+) CD8+ T cells were sequestered in epithelial (CD326+) lung niches and secreted granzyme B and perforin, indicating cytotoxic potential. Infected mice also developed antibodies against the SARS-CoV-2 viral proteins. Hence, HIS-DRAGA mice showed unique advantages as a surrogate in vivo human model for studying SARS-CoV-2 immunopathology and for testing the safety and efficacy of candidate vaccines and therapeutics.
Trace and Toxic Metals in Wetlands-A Review.

The mobility and plant availability of many trace and toxic metals in wetland soils is often substantially different from upland soils. Oxidation-reduction (redox) and associated pH changes that occur in soils as a result of flooding or drainage can affect the retention and release of metals by clay minerals, organic matter, iron oxides, and, for coastal wetlands, sulfides. Except where a flooded soil or sediment becomes strongly acid upon drainage and oxidation, as sometimes occurs, the processes immobilizing metals tend to be complimentary such that large-scale metal releases from contaminated soils and sediments do not occur with changing redox conditions. Metals tend to be retained more strongly in wetland soils compared with upland soils.
Proteins and direct methods

Conventional direct methods, which work so well for small structures, are less successful for macromolecules. Where it has been demonstrated that a solution might be found using direct methods it is then found that the usual figures of merit are unable to distinguish the few good sets of phases from the large number of sets generated. The reasons for the difficulties with very large structures are considered from a first-principles approach taking into account both the factors of having a large number of atoms and low resolution data. A proposal is made for trying to recognize good phase sets by taking a large structure as a sum of a number of smaller structures for each of which a conventional figure of merit can be applied.
Synthesis of 5-ortho-Carboranylsalicylaldehyde and an Indolinospirobenzopyran

Abstract 5-ortho-Carboranylsalicylaldehyde was prepared from 5-iodosalicylaldehyde in six steps in 18% overall yield, and also from 5-iodosalicylic acid in seven steps in 45% overall yield. The reaction of 5-ortho-carboranylsalicylaldehyde with Fischer's base gave a spiropyran in 63% yield.
Phase separation in polyetherimide/solvent/nonsolvent systems and membrane formation

Phase separation phenomena of polyetherimide (PEI)/solvent/nonsolvent systems were investigated by measuring their precipitation values over the temperature range from 20 to 50°C. The solvents used are N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAC), and dimethylformamide (DMF). Nine nonsolvents were employed including water, methanol, ethanol, 1-propanol, 2-propanol, acetic acid, propionic acid, ethylene glycol, and diethylene glycol. Based on the measured precipitation values, critical solubility parameters for PEI were calculated, and the partial solubility boundary for PEI was obtained in a two-dimensional solubility parameter coordinate graph. The relationship between solvent strength and membrane structure was examined using PEI hollow-fiber membranes prepared from binary polymer solutions containing NMP, DMAC, and DMF as solvents. Water was used both as internal and external coagulants. The cross-sectional structure and gas permeation properties of these hollow fibers were examined. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1789–1796, 1999
Efecto sinérgico de la ceniza volante con micro polvo de carbonato de calcio para el mejoramiento de la durabilidad de concretos autocompactables

El uso del concreto autocompactable ha ido incrementando en la industria de la construccion, como reemplazo del concreto vibrado convencional, desde su primer uso en Japon a finales de los anos ochenta. Sin embargo, aun existen algunas dudas sobre la durabilidad de los concretos autocompactables comparados con los concretos vibrados convencionales. Una de las diferencias mas importantes entre el concreto autocompactable y el concreto vibrado convencional es la incorporacion de aditivos minerales en el primero. Estos aditivos minerales se utilizan para mejorar algunas propiedades en estado fresco y endurecido del concreto autocompactable, asi como para reemplazar parte de los altos contenidos de cemento Portland que tienen estos concretos. En este estudio se investigo el efecto de la sustitucion de cemento Portland por dos aditivos minerales (ceniza volante y un micro-polvo de carbonato de calcio con un tamano promedio de particula de 0.7 µm), en indicadores de durabilidad de los concretos autocompactables, tales como: carbonatacion, permeabilidad a los iones cloro y resistividad electrica, asi como en otras propiedades en estado fresco y endurecido. Con esta investigacion se lograron determinar las combinaciones optimas de ceniza volante y micro-polvo de carbonato de calcio en los indicadores de durabilidad previamente mencionados.
New Generation of Multifunctional Nanoparticles for Cancer Imaging and Therapy

Advances in nanotechnology have contributed to the development of novel nanoparticles that enable the tumor‐specific delivery of imaging probes and therapeutic agents in cancer imaging and therapy. Nanobiotechnology combines nanotechnology with molecular imaging, which has led to the generation of new multifunctional nanoparticles for cancer imaging and therapy. Multifunctional nanoparticles hold great promise for the future of cancer treatment because they can detect the early onset of cancer in each individual patient and deliver suitable therapeutic agents to enhance therapeutic efficacy. The combination of tumor‐targeted imaging and therapy in an all‐in‐one system provides a useful multimodal approach in the battle against cancer. Novel multifunctional nanoparticles thus offer a new avenue in the application of personalized medicine in the near future. Herein, new trends and the significance of novel multifunctional nanoparticles in cancer imaging and therapy are reviewed.
Crystal Structure of the Transition‐Metal Molybdates. I. Paramagnetic Alpha‐MnMoO4

Paramagnetic alpha‐MnMoO4, the stable phase at STP, is monoclinic with lattice constants a=10.469±0.005, b=9.516±0.005, c=7.143±0.005 A, and β=106°17′±6′, and space group C2/m. The crystal structure has been solved and refined by a combination of three‐dimensional Patterson and Fourier series and by the method of least squares. 1873 independent integrated intensities were measured by PEXRAD; the final agreement factor between measured and calculated structure factors is 0.0574. Two crystallographically independent Mn atoms are surrounded by highly distorted oxygen octahedra; the Mn–O distance varies between 2.091±0.006 and 2.252±0.003 A, with average length 2.164 A. Two crystallographically independent Mo atoms are surrounded by slightly distorted oxygen tetrahedra, with Mo–O distances ranging from 1.724±0.005 to 1.851±0.004 A, the average being 1.761 A. The thermal vibrations are significantly anisotropic. An analysis is given of various current methods for estimating the standard deviation in the measur.
Effect of minimal processing operations on the quality of garlic, green onion, soybean sprouts and watercress

The effect of unit operational procedures on the quality of minimally processed vegetables was investigated. Peeling methods were studied for garlic, while different preparation forms were tried for garlic, green onion and soybean sprouts. Washing and a mild heat treatment, at 60°C for 30 s, were investigated as measures to reduce microbial populations of minimally processed vegetables. With garlic it was found that dry peeling was better than wet peeling in reducing microbial populations and preserving ascorbic acid content. Removal of the root, a potential source for microbial contamination, reduced microbial load in garlic. For garlic and green onion, microbial quality deteriorated with severity of cutting. Washing reduced microbial counts of prepared vegetables. Repeated washing and use of chilled water further reduced the counts. A mild heat treat-ment markedly reduced microbial counts in soybean sprouts and watercress, which were highly loaded with microorganisms. Sensitivities of vegetables to heat treatment differ and may limit the usefulness of heat treatment for some products. © 1998 SCI.
A universal surface complexation framework for modeling proton binding onto bacterial surfaces in geologic settings

Adsorption onto bacterial cell walls can significantly affect the specia- tion and mobility of aqueous metal cations in many geologic settings. However, a unified thermodynamic framework for describing bacterial adsorption reactions does not exist. This problem originates from the numerous approaches that have been chosen for modeling bacterial surface protonation reactions. In this study, we compile all currently available potentiometric titration datasets for individual bacterial species, bacterial consortia, and bacterial cell wall components. Using a consistent, four discrete site, non-electrostatic surface complexation model, we determine total func- tional group site densities for all suitable datasets, and present an averaged set of 'universal' thermodynamic proton binding and site density parameters for modeling bacterial adsorption reactions in geologic systems. Modeling results demonstrate that the total concentrations of proton-active functional group sites for the 36 bacterial species and consortia tested are remarkably similar, averaging 3.2 1.0 (1) 10 4 moles/wet gram. Examination of the uncertainties involved in the development of proton-binding modeling parameters suggests that ignoring factors such as bacterial species, ionic strength, temperature, and growth conditions introduces relatively small error compared to the unavoidable uncertainty associated with the determination of cell abundances in realistic geologic systems. Hence, we propose that reasonable estimates of the extent of bacterial cell wall deprotonation can be made using averaged thermodynamic modeling parameters from all of the experiments that are considered in this study, regardless of bacterial species used, ionic strength, temperature, or growth condition of the experiment. The average site densities for the four discrete sites are 1.1 0.7 10 4 , 9.1 3.8 10 5 , 5.3 2.1 10 5 , and 6.6 3.0 10 5 moles/wet gram bacteria for the sites with pKa values of 3.1, 4.7, 6.6, and 9.0, respectively. It is our hope that this thermodynamic framework for modeling bacteria-proton binding reactions will also provide the basis for the development of an internally consistent set of bacteria-metal binding constants. 'Universal' constants for bacteria-metal binding reactions can then be used in conjunc- tion with equilibrium constants for other important metal adsorption and complex- ation reactions to calculate the overall distribution of metals in realistic geologic systems.
Effect of irradiation on ethyl 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carboxylate: an ESR study

Ethyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate [C11H15NO2S] was synthesized by the Gewald method. Its single crystals were grown from an alcohol/ethyl acetate solution at 15 °C and characterized using IR and 1H-NMR. These single crystals were irradiated for 72 h at 298 K by a 60Co gamma source with a dose speed of 0.864 kGy/h. After irradiation, electron spin resonance (ESR) measurements were carried out to study radiation-induced radicals in the temperature range from 120 to 450 K. Additionally, for the single crystal, ESR angular dependencies were measured in the xy, xz and yz planes of the substance. This irradiated single crystal was analyzed based on the ESR spectra. Analysis of the spectra revealed that the radical was formed by a C–H bond fission at the carbon end of the substance. It was also observed that the color of the sample changed after irradiation. The hyperfine and g parameters were determined from the experimental spectra. It was inferred from these results that the hyperfine parameters and g value exhibited anisotropic behavior. The average values of these parameters were calculated as follows: g = 2.0088, AH1=H2 = 20.70 G, AH3=H4 = 10.80 G, AHa = 4.59 G, AHb = 3.24 G and, AN = 6.10 G. Copyright © 2011 John Wiley & Sons, Ltd.