Miracle-dz/UniFAR-FTUs huggingface dataset:
An Eco‐friendly Soft Template Synthesis of Mesostructured Silica‐Carbon Nanocomposites for Acid Catalysis

The synthesis of ordered mesoporous silica‐carbon composites was explored by employing TEOS and sucrose as the silica and carbon precursor respectively, and the triblock copolymer F127 as a structure‐directing agent via an evaporation‐induced self‐assembly (EISA) process. It is demonstrated that the synthesis procedures allow for control of the textural properties and final composition of these silica‐carbon nanocomposites via adjustment of the effective SiO2/C weight ratio. Characterization by SAXS, N2 physisorption, HRTEM, TGA, and 13C and 29Si solid‐state MAS NMR show a 2D hexagonal mesostructure with uniform large pore size ranging from 5.2 to 7.6 nm, comprising of separate carbon phases in a continuous silica phase. Ordered mesoporous silica and non‐ordered porous carbon can be obtained by combustion of the pyrolyzed nanocomposites in air or etching with HF solution, respectively. Sulfonic acid groups can be readily introduced to such kind of silica‐carbon nanocomposites by a standard sulfonation procedure with concentrated sulfuric acid. Excellent acid‐catalytic activities and selectivities for the dimerization of styrene to produce 1,3‐diphenyl‐1‐butene and dimerization of α‐methylstyrene to unsaturated dimers were demonstrated with the sulfonated materials.
Partitioning Behavior of Penicillin G in Aqueous Two Phase System Formed by Ionic Liquids and Phosphate

Abstract An aqueous two‐phase system (ATPS) was presented with hydrophilic ionic liquid 1‐butyl‐3‐methylimidazolium chloride ([Bmim]Cl) and NaH2PO4 aqueous solution in this paper. The partitioning behavior of penicillin G in the ATPS was investigated. Concentrations of NaH2PO4, penicillin G, and [Bmim]Cl were evaluated to determine their effects on the partition coefficient and extraction yield of penicillin G. It was found that both of partition coefficient and extraction yield strongly depended on the concentration of [Bmim]Cl, penicillin and NaH2PO4. A high extraction yield of 93% was achieved with the following parameters: NaH2PO4 · 2H2O 40% (wt%), penicillin 45000∼50000 u/ml, [Bmim]Cl 20∼21% (wt%). The [Bmim]Cl/NaH2PO4 system was also applied in a real filtration of penicillin G fermentation broth and the extraction yield was averaged at 91.5%. It is worthy noting that the working pH value of ATPS was at the range of 5∼6, no emulsification and protein denaturation could be observed.
Finite-Length Models of Carbon Nanotubes Based on Clar Sextet Theory

Finite-length models of metallic and semiconducting carbon nanotubes (CNTs) based on Clar sextet theory of aromatic systems are proposed. For metallic CNTs, the electronic properties of finite-length models converge monotonically to the values expected for quasi-monodimensional metallic systems. For semiconducting CNTs, the use of finite-length models as proposed in this work leads to a fast convergence of the electronic properties to the values expected for the corresponding infinite-length nanotube.
Synthesis of Novel bis-Phosphonate Derivatives by Pudovik Reaction

Abstract Synthesis of novel bis-(3-methyl-5-nitro-2-oxo-2,3-dihydro-2λ 5benzo[1,3,2]oxazaphosphol-2yl)substituted aryl methanes was accomplished by Pudovik reaction. Addition of equimolar quantities of 2-methylamino-4-nitro phenol (1) and ethanol to PCl3 afforded cyclic condensation product. On reaction with respective aldehydes followed by treatment with phosphorus(III) monochloride of 1, and on subsequent reaction at reflux temperature, this rearranged from P(III) to P(V) state. Their structures were determined by IR, 1H NMR, 13C NMR, 31P NMR, and mass spectral data.
Measurement of the potentially available charge and the dissociation behaviour of humic acid from cobaltihexammine adsorption

SUMMARY The use of a new method for characterizing humic acids based on the measurement of the cobaltihexammine cation exchange capacity (CEC) vs. pH is examined. The method was first verified on a macroporous weak-acid cation exchange resin: charge vs. pH curves and pK values from cobaltihexammine adsorption identify with results from discontinuous acid-base titrations at high ionic strength (5 M). Similar agreement was obtained for humic acids from a Podzol soil: the cobaltihexammine-CEC identifies with the macromolecular charge (from continuous acid-base titrations) at ionic strength of 3 and 5 M, but slightly underestimates (5%) the humic acid charge at 1 M ionic strength. The cobaltihexammine method is suitable for determining the potentially available charge in the pH range 2 to 12 and the intrinsic pK values of humic acids.
Affinity Chromatography And Metal Chelate Affinity Chromatography

The extremely rapid growth in the field of protein chemistry during the past 50 years has been due in large part to the development of very effective techniques of protein separation and analysis. A number of techniques such as electrophoresis or isoelectric focusing, based on the overall charge and mass of a biomolecule, have been widely applied. However, preparative isolation of proteins often involves some form of chromatography. The two modes of chromatography that have been most widely accepted and used for separation of biomolecules are partition chromatography and adsorption chromatography which includes affinity chromatography. The technique of affinity chromatography exploits the unique biological specificity inherent in a ligand-macro-molecule interaction. Thus, among separation procedures, a group of methods based on the molecular affinities found in biological systems have become increasingly important.
High-throughput screening using the surface plasmon resonance effect of colloidal gold nanoparticles

We propose a high-throughput screening method which involves colloidal gold nanoparticles sensitized with the binding protein. Upon interaction with a specific ligand (a polypeptide or a small organic molecule), the surface plasmon resonance absorbance peak of the colloidal gold reagent shifts toward longer wavelengths due to the change in refractive index at the particle surface caused by changes in mass. The shift is proportional to the dose of ligand involved for a fixed amount of binding protein and occurs according to the kinetics of interaction. We applied this property to the analysis of association and dissociation of ligand–binding protein interactions in a small random access clinical chemistry analyzer. The instrument measures the changes in A600 nm over a period of 20 min for each sample. Due to the high degree of automation, the instrument throughput amounts to 144 samples an hour and can be run during 24 h a day in a walk-away mode. When connected to a computer for data handling, a single instrument can consequently handle over 3000 samples a day. Higher throughput instruments are available which can handle as much as ten times more samples. We validated the technique by comparing the affinity constants (range 103−1012 mol−1) calculated for 30 pairs of ligand-protein interactions at different ligand doses with those obtained from other methods, including the BIAcore (slope 0.84; coefficient of correlation r = 0.82).
Investigation of Structural and Electrical Properties of Polyaniline/Gold Nanocomposites

Gold nanoparticles are synthesized by the reduction of gold salt using extract of tea leaves in 1-methyl-2-pyrrolidinone (NMP) solution. Transmission electron microscopy (TEM) confirmed the formation of gold nanoparticles having average size of ∼20 nm. These nanoparticles have been incorporated in NMP solution of polyaniline emeraldine base (PANIEB) to cast the nanocomposite films. Thermogravimetric analysis (TGA) revealed that the thermal stability of the nanocomposites has improved as compared to the pure PANI. TEM confirmed the presence of gold nanoparticles in polyaniline matrix. The impedance spectroscopic studies showed that gold nanoparticles have considerable effects on the electrical properties of PANI by reducing the charge trapping centers and increasing conducting channels, which causes substantial decrease in the real part of impedance.
An automated enantioselective isolation system for the study of estrogenic potencies: Study of the estrogenic activity of α‐hexachlorocyclohexane

Herein we describe an automated enantioselective isolation system that uses a gas chromatograph-flame ionization detector (FID)-preparative fraction collector to separate the enantiomers of chiral compounds. In this system, a switching device was coupled with six glass tubes containing an organic solvent for the separate collection of six compounds, thus eliminating the need for a manual collection procedure after separation by gas chromatography. To evaluate the usefulness of this system, we applied it to the separation and collection of the enantiomers of α-hexachlorocyclohexane (α-HCH), and we measured the estrogenic potency of each enantiomer by means of an MVLN cell (Michigan Cancer Foundation-7 (MCF-7) cell stably transfected with a pVit-tk-LUC reporter plasmid) bioassay and an estrogen receptor binding assay. The variability in the retention time of each enantiomer (relative standard deviation, n = 16) was typically < 0.05%. The recoveries of the dextrorotatory (+) and levorotatory (–) enantiomers of α-HCH were about 68.8% and 73.4%, respectively. The overall quantity of each enantiomer of α-HCH collected was about 300 μg. Both enantiomers of α-HCH showed similar estrogenic activity. On the basis of the results obtained for α-HCH, we concluded that this analytical method is suitable for the determination of the estrogenic activity of other chiral compounds. Such determinations are essential because enantiomers differ considerably in how they accumulate in organisms and decompose in the environment.
Collision Broadening in the Argon Spectrum

High resolution photographs of the near infra-red spectrum of an argon discharge at various pressures revealed that lines whose lower levels are connected by resonance transitions to the ground state suffered markedly greater collision broadening than those whose lower levels are metastable. The excessive broadening of the former group of lines is believed to be due to resonance collision broadening of their lower levels. The collision broadening of one line from each group, namely 1s2 - 2p2, λ8264 A and 1s5 - 2p2, λ6965 A, was measured. The half intensity collision width of λ8264 was 14.7 ± 1.0 × 10-20 cm-1 per atom per cm3 of argon, while that of λ6965 was 2.0 ± 0.3 × 10-20 cm-1 per atom per cm3 of argon. The ratio of collision width to collision shift (the latter being taken from Hindmarsh and Thomas 1959) was 3.1 ± 0.8. This is in agreement with the value 2.75 predicted by the Lindholm theory for interaction due to van der Waals forces between the atoms. The resonance broadening of λ8264 is related to the f-value of the argon resonance line 1p0 - 1s2, λ1048, and this is found to be f=0.13 ± 0.03, in agreement with calculations quoted by Knox in 1958.
Hidden Second Oxidation Step of Hummers Method

Hummers method has been used for 50 years to prepare graphene oxide (GO) by oxidizing graphite using Mn2O7. In this work, a new angle on Hummers method is described. The oxidation procedure before the addition of water, which has been respected as the main oxidation step of Hummers method, is named step I oxidation, and the widely ignored further oxidation step after the addition of water is named step II oxidation. The chemical and structural evolutions during step II oxidation was demonstrated for the first time using various techniques including atomic force microscopy (AFM), dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible light (UV–vis) spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), 13C nuclear magnetic resonance (NMR), and zeta-potentiometry. Step II oxidation influences the size of GO, defects within the layers, and functional groups on the surface, which affect the thermal stability of GO and the properties of resultant thermally reduced G.
Potential urine biomarkers from a high throughput metabolomics study of severe sepsis in a large Asian cohort

Severe sepsis (SS) is a main cause of death in hospitalized patients worldwide. There is an urgent need for accurate biomarkers for early diagnosis of SS. Metabolomics technologies allow high-throughput screening of metabolite biomarkers. Non-targeted mass spectrometry (MS) was used to characterize sensitive and economical peripheral biomarker(s) associated with the urine metabolome from SS patients. In this study, urine samples were obtained from controls and age-matched patients with SS. Metabolic differences among SS and control subjects were identified based on orthogonal signal correction-partial least squares discriminant analysis. Sphingosine, 5-methylcytidine, 3-dehydrocarnitine, 4-acetamido-2-aminobutanoic acid and phenyllactic acid in the SS subjects were significantly different from the control subjects. The receiver operating characteristic curve of the differential expression of these metabolites was also performed to demonstrate the utility of these biomarkers for diagnosis of SS. Three metabolites comprising sphingosine, 5-methylcytidine and 3-dehydrocarnitine were selected as candidate biomarkers and validation in separate and independent patient cohorts. Mass-spectrometry urine profiling proved to be an efficient and convenient tool for diagnosis and screening of SS in a high-risk population.
Functional Mesoporous Carbon‐Coated Separator for Long‐Life, High‐Energy Lithium–Sulfur Batteries

The lithium–sulfur (Li–S) battery is regarded as the most promising rechargeable energy storage technology for the increasing applications of clean energy transportation systems due to its remarkable high theoretical energy density of 2.6 kWh kg−1, considerably outperforming today's lithium‐ion batteries. Additionally, the use of sulfur as active cathode material has the advantages of being inexpensive, environmentally benign, and naturally abundant. However, the insulating nature of sulfur, the fast capacity fading, and the short lifespan of Li–S batteries have been hampered their commercialization. In this paper, a functional mesoporous carbon‐coated separator is presented for improving the overall performance of Li–S batteries. A straightforward coating modification of the commercial polypropylene separator allows the integration of a conductive mesoporous carbon layer which offers a physical place to localize dissolved polysulfide intermediates and retain them as active material within the cathode side. Despite the use of a simple sulfur–carbon black mixture as cathode, the Li–S cell with a mesoporous carbon‐coated separator offers outstanding performance with an initial capacity of 1378 mAh g−1 at 0.2 C, and high reversible capacity of 723 mAh g−1, and degradation rate of only 0.081% per cycle, after 500 cycles at 0.5 C.
Improvement of Thermal and Mechanical Properties of a Phenolic Resin Nanocomposite by In Situ Formation of Silsesquioxanes from a Molecular Precursor

Silsesquioxanes are formed in situ during mixing and curing of a phenolic resin and a molecular sil- ane precursor (3-(triethoxysilyl)-1-propaneamine) yielding a nanocomposite. As indicated by a higher onset tempera- ture, a higher characteristic decomposition temperature, and a lower maximum heat flow, the thermal stability of the nanocomposite is significantly improved over the pris- tine resin. Moreover, the bending strength and the strain at break could also be enhanced by 36% and 51%, respec- tively. The nanocomposite was characterized by 29 Si solid- state NMR, STEM/EDS, TGA, DSC, and three point bending tests. The STEM/EDS measurements showed a homogenous distribution of silsesquioxanes in the pheno- lic resin. V C 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 2272-2277, 2010
Critical evaluation of LC-MS-based methods for simultaneous determination of deoxynivalenol, ochratoxin A, zearalenone, aflatoxins, fumonisins and T-2/HT-2 toxins in maize

The results of a proficiency test for the LC-MS/(MS) determination of up to 11 mycotoxins (aflatoxins B1, B2, G1 and G2, fumonisins B1 and B2, ochratoxin A, deoxynivalenol, T-2 and HT-2 toxins and zearalenone) in maize were evaluated to identify possible strengths and weaknesses of various methodologies used by the 41 participating laboratories. The majority of laboratories (56%) used mixtures of acetonitrile:water for extraction. Other laboratories used methanol:water mixtures (17%) or performed two consecutive extractions with phosphate buffer solution (PBS) followed by methanol (15%). Few laboratories used mixtures of acetonitrile:water:methanol (7%), water:ethyl acetate (2.5%) or PBS alone (2.5%). The majority of laboratories (58%) used a clean-up step prior to chromatography. The remaining laboratories analysed crude extracts (37%) or used a mixed approach (5%). The amount of sample equivalent injected into LC-MS/(MS) ranged between 0.1-303 mg for purified extracts and 0.08-20 mg for directly analyse.
Evaluation of Sweet Sorghum (Sorghum bicolour (L.) moench) Bagasse by Chemical, in sacco and in vivo Techniques in Graded Murrah Buffalo Bulls

Sweet sorghum (Sorghum bicolour (L.) moench) bagasse (SSB) a by-product obtained after juice extraction from the stalks of sweet sorghum was evaluated as potential roughage source for ruminants using in sacco degradability of dry matter and protein besides in vivo nutritive value. The crude protein (CP) and neutral detergent fibre (NDF) content of SSB were 3.94 and 74.76 per cent, respectively. The in sacco effective degradable dry matter (EDDM) and effective rumen degradable protein (ERDP) per cent of SSB were 40.60 and 55.30, respectively. The digestible crude protein (DCP) and total digestible nutrients (TDN) values of SSB were 1.58 and 51.59 per cent, respectively in graded Murrah buffalo bulls. The study inferred that the chemical composition and nutritive value of SSB are comparable to sorghum straw and may be used as an alternative roughage source four times more economical than sorghum straw in ruminant rations.
XPS in development of chemical sensors

XPS represents a powerful tool for investigation of chemistry involved in chemical sensors, as analytes and recognition elements interact at a device surface, the region analyzed by the spectroscopic technique. In this way, the processes involved in preparation, operation and limiting life of sensors can be unraveled. Application of XPS to (bio)chemical sensors is reviewed with particular attention to electrochemical sensors, which account for more extensive literature. Systems based on polymers, organic mono/multilayers, carbon nanotubes and graphene, metallic species, also in the nanostructure format, and bioreceptors and relevant composites have been considered with a special focus on the information provided by XPS analysis on such (bio)sensing systems, highlighting the role played by XPS in sensor technology and giving at the same time an idea of what is still missing in this field thus advancing possible future uses of XPS in sensing technology.
Phenol Accumulation in the Larvae of the Species Agrion puella L.(Insecta, Odonata) under Laboratory Conditions

In an aerated batch experiment for one to six days the phenol accumulation is investigated in the surviving and killed larvae of Agrion puella at phenol concentrations of 50 to 200 mg/l in the medium. The rate of mortality increases with the initial concentration of phenol, although about 40% phenol is microbially digested during the test. The phenol accumulation in μg/g wet substance is always higher in the surviving individuals than in the killed ones, but it shows an identical time trend for both. On the first day, accumulation is high, and till the third day it decreases. On the fourth day, it reaches a maximum, and then it drops sharply to its minimum on the sixth day. The measured actual accumulation is the result of changing intake and elimination rates, especially the elimination rates decreasing with increasing duration of tests and test concentration due to metabolic disturbances. The absolute minimum on the sixth day is determined also by the reduced phenol concentration. The limit of accumulation for a chronic poisoning can be estimated at 70 μg/g phenol.
Optimizing Struvite Production for Phosphate Recovery in WWTP

Struvite, a crystalline structure comprised of ions of magnesium Mg +2 , ammonium NH4 -N , and phosphate PO4 -P ,i s commonly encountered in wastewater treatment plants WWTPs through struvite encrustation. The gradual accumulation of this crystal in pipes and fittings leads to high costs due to downtime and replacement of parts. Technologies that are used to reduce this problem are ideally located in biological nutrient removal plants downstream of anaerobic digesters, as high levels of NH4 - N and PO4 - P typically characterize anaerobic digester supernatants. In 2003-2004, two technical-scale, struvite recovery studies were conducted on-site at the City of Penticton, B.C., Canada and the City of Richmond, B.C., Canada using a novel technology developed by the environmental engineering group at the University of British Columbia. The results of these studies showed an average reduction of 80% in phosphate and a dense, spherical product, 5-10 times larger than any commercially available struvite to date. Overall, the recovery of struvite has enormous commercial potential, which results in WWTP becoming more sustainable, concurrently reducing problems typically associated with their operation.
Determination of pesticide residue in vegetable juice, fruit juice and green tea solution in closed package

Determination of pesticide residue in 25 closed-package samples of vegetable juice, fruit juice and green tea solution revealed pesticide residue in 20 samples. Pesticides that were frequently found were heptachlor and lindane. We found heptachlor 0.025-0.060 ppm in green tea and the amounts from 2 of 5 samples were over the permissible level. Lindane was also found at 0.005-0.014 ppm. Lindane is a nonpermitted pesticide. In apple juice, we found hepatachlor 0.040 ppm, lindane 0.007 ppm, aldrin 0.010 ppm which were within the allowable limit. In foreign carrot juice samples, we found heptachlor 0.030 ppm, o,p'-DDD 0.600 ppm and B-endosulphan 0.240 ppm. The amount of o,p'-DDD in foreign carrot juice was over the limit and B-endesulphan is a nonpermitted pesticide. We found that the Thai carrot juice consisted of heptachlor 0.020 ppm and G-chlordane 0.400 ppm. G-chlordan is also a nonpermitted pesticide. We found pesticide residue in grape juice that might be abamectin. We did not find any pesticide residue in orange juice. These results from our investigations should stimulate the Ministry of Public Health to be interested in controlling the use of pesticides in packaged juices and teas.
The layered ternary germanium tellurides ZrGeTe4, HfGeTe4, and TiGeTe6: structure, bonding, and physical properties

The new ternary chalcogenides zirconium germanium tetratelluride (ZrGeTe 4 ), hafnium germanium tetratelluride (HfGeTe 4 ), and titanium germanium hexatelluride (TiGeTe 4 ) have beeen synthesized, and their structures have been determined by single-crystal X-ray diffraction methods. The compounds ZrGeTe 4 and HfGeTe 4 are isostructural. They crystallize in space group C 2υ 12 -Cmc2 1 of the orthorhombic system with four formula units in cells of dimensions a=3.976(4), b=15.876(16), c=10.948(12) A (ZrGeTe 4 ) and a=3.963(3), b=15.875(10), c=10.941(7) A (HfGeTe 4 ) at 113 K
PROTECTIVE PROPERTIES AND SPECTRAL ANALYSIS OF NITROGEN- AND OXYGEN-CONTAINING CORROSION INHIBITORS FOR OIL EQUIPMENT

The protective properties of six corrosion inhibitors based on imidazolines, amides, amines and esters have been determined using gravimetric and potentiometric methods. The effect of inhibitor solvent on the protective properties has been examined. The dependence of inhibitor protective effect upon the content of nitrogen and functional groups has been determined. The most effective inhibitors have been chosen and their IR-spectra have been shown.