Miracle-dz/UniFAR-FTUs huggingface dataset:
Review: Lanthanide coordination chemistry: from old concepts to coordination polymers

Because of their remarkable and unmatched optical and magnetic properties, the lanthanides are under the limelight when it comes to high technology. These elements are used in strategic applications such as optical glasses and lasers, telecommunications, lighting and displays, magnetic materials, hard-disk drives, security inks and counterfeiting tags, catalysis, biosciences, and medicine, to name but a few. Long considered as minor actors in transition metal chemistry, they have now gained respect from coordination chemists who insert them into sophisticated functional and polyfunctional molecules and materials. This mini review focuses on trivalent lanthanide ions and first summarizes their basic properties. Then some classical aspects of their coordination chemistry are discussed, followed by macrocyclic chemistry, supramolecular chemistry, and self-assembly processes. The last part of this contribution deals with coordination polymers and hybrid materials including potential applications. Graphical Abstract
Photoinduced Charge Separation in Reverse Micelles Prepared with Benzylhexadecyldimethylammonium Chloride (BHDC). The Electron‐Transfer Reaction between Pyrene and N,N‐Dimethylaniline *

Laser flash photolysis was used to investigate the formation of radical ions produced in the quenching of the pyrene‐N,N'‐dimethylaniline exciplex by reverse micelles made with benzylhexadecyldimethylammonium chloride (BHDC) dispersed in benzene or chlorobenzene. The radical ion quantum yields, φion, were determined as a function of BHDC concentration and the amount of water dispersed. They were strongly dependent on the composition of the media. The charge separation was more effective in the BHDC‐benzene than in the BHDC‐chlorobenzene system. The results are discussed in terms of the properties of the micellar interface and the fast exchange of material produced by collisions between reverse micelles.
The mass spectrometry of polychlorinated dibenzo‐p‐dioxins

The negative ion chemical ionization mass spectra of polychlorinated dibenzo-p-dioxins using oxygen, methane and methane/oxygen are reported together with their methane positive ion chemical ionization mass spectra and conventional electron impact spectra. The methane/oxygen negative ion chemical ionization mass spectra proved to be the most useful of the negative ion spectra for structure determination.
Biofiltration of concentrated mixtures of hydrogen sulfide and methanol

To date, little research has addressed biofiltration of volatile organic compound (VOC) and reduced sulfur compound (RSC) mixtures at the relatively high concentrations (0 to 450 ppm v ) of interest to the pulp and paper industry. The objectives of this study were to assess the impact of cotreatment on the biofiltration of air emissions containing mixtures of RSCs and VOCs, and to develop models of the processes. Experiments were conducted at various concentrations (16's EBRT) using hydrogen sulfide as a model RSC (0-450 ppm v ) and methanol as a model VOC (0-400 ppm v ). Reaction-limited and biofilm models showed that hydrogen sulfide degradation followed Monod kinetics, while methanol removal was first order. The maximum hydrogen sulfide removal rate observed during the first three months of operation was 144 g H 2 S/m 3 bed/h. However, this declined to 85-95 g H 2 S/m 3 bed/h in subsequent months. The methanol removal rate was 70-80% of the applied load (maximum 480 g methanol/m 3 bed/h) for single component and mixture treatment. The results indicate that methanol and hydrogen sulfide removal in biofilters are independent and that co-treatment is an attractive option.
Oxidation states of the transition metal cations in the highly nonstoichiometric perovskite-type oxide Ba0.1Sr0.9Co0.8Fe0.2O3−δ

The oxidation states of Fe and Co in the complex perovskite-type oxide Ba0.1Sr0. 9Co0.8Fe0. 2O3−δ were determined by means of X-ray absorption near edge structure (XANES) spectroscopy. Measurements performed in situ for 783 ≤ T/K ≤ 918 and 50 ≤ pO2/Pa ≤ 2 × 104 reveal that the electrons generated by reduction are not equally distributed between the Fe and Co cations. A comparison with thermogravimetric measurements indicates a discrepancy in the amount of oxygen lost from the sample. This discrepancy is an indication that not only are the transition metal cations reduced but the oxygen anions are, too. A model explaining the observed behaviour is proposed.
Transport of Nutrients and Postemergence-Applied Herbicides during Corrugation Irrigation of Wheat.

The nutrient and pesticide content in runoff water from surface irrigations can adversely affect the quality of receiving waters, and can also determine the suitability of the water for reuse in the subsequent downstream irrigation of other crops. In order to assess the magnitude of loss under normal corrugation irrigation practices, the transport of plant nutrients and postemergence-applied herbicides was monitored in runoff water from two irrigations of a 12.6-ha wheat (Triticum aestivum L. cv. Owens) field. Cumulative P and N losses in runoff water from both irrigations were 1007 and 2487 g, respectively, which corresponded to 0.29 and 0.13% of the amounts applied through fertilization. Loss of either nutrient in the first irrigation was approximately twice that in the second irrigation. Total losses of dicamba (3,6-dichloro-2-methoxybenzoic acid), MCPA [(4-chloro-2-methylphenoxy)acetic acid] and diclofop[(±)-2-[4-(2,4-dichlorophenoxy)phenoxy]propanoic acid] from the experimental site were 3.0, 9.3, and 22.8 g, respectively, which corresponded to approximately 0.2% of the amount of each herbicide applied to the wheat. Of these losses, the majority (≈97%) was transported during the first irrigation. Irrigation efficiency was 70% for the first irrigation and mean nutrient fluxes in the resulting runoff were 0.79 and 1.92 g ha-1 h-1 for P and N, respectively, with corresponding weighted concentration means of 253 and 617 μg L-1 . Herbicide fluxes were 3.1, 9.8, and 23.3 mg ha-1 h-1 for dicamba, MCPA, and diclofop, respectively. Corresponding weighted concentration means were 1.0, 3.2, and 7.7 μg L-1 . Nutrient and herbicide weighted concentration means were below Canadian Water Quality Guidelines for both drinking and irrigation water. Maximum P and diclofop concentrations exceeded drinking water guidelines, whereas those for dicamba and MCPA exceeded interim guidelines for irrigation water.
Atmospheric fate of carbonyl oxidation products originating from α-pinene and Δ3-carene : Determination of rate of reaction with OH and NO3 radicals, UV absorption cross sections, and vapor pressures

Large yields of dicarbonyl compounds have been found in the atmospheric oxidation of α-pinene and Δ3-carene. These terpenes are emitted in large quantities by biogenic sources, and it is important to know the fate of their reaction products. In this investigation, ultraviolet and infrared absorption cross sections, vapor pressures, and rate coef ficients for hydroxyl and nitrate radical reactions have been determined for the main product in each case, i.e., 3-acetyl-2,2-dimethylcyclobutaneacetaldehyde (pinonaldehyde) and 2,2-dimethyl-3-(2-oxopropyl)cyclopropaneacetaldehyde (caronaldehyde). Photolysis lifetimes at noon on July 1 at 50° N using a photolysis quantum yield of 1 are 3.3 h for pinonaldehyde and 5.8 h for caronaldehyde. The infrared absorption cross sections obtained (base e) were (8.08 ± 0.32) × 10-19 and (1.04 ± 0.05) × 10-18 cm2 molecule-1 for pinonaldehyde and caronaldehyde at 1725.4 and 1741.5 cm-1, respectively. Vapour pressures determined by Knudsen effusion measurements are 5.1 and 3.0 P.
Carbon‐13 NMR spectra of bile acid derivatives. Part III . Unsaturated 5β‐cholanoic acids

13C NMR signals were assigned for 18 methyl 5β‐cholenoates with a double bond in ring A, B, C or D (Δ2, Δ3, Δ5, Δ6, Δ7, Δ8(14), Δ9(11), Δ11 or Δ14). The double bond substituent effects on the 13C NMR chemical shifts of the parent 5β‐cholanoates were clarified.
Plasticized polylactide/clay nanocomposites. I. The role of filler content and its surface organo‐modification on the physico‐chemical properties

Polylactide (PLA)-layered silicate nanocomposites plasticized with 20 wt % of poly(ethylene glycol) 1000 were prepared by melt blending. Three kinds of organo-modified montmorillonites—Cloisite® 20A, Cloisite® 25A, and Cloisite® 30B—were used as fillers at a concentration level varying from 1–10 wt %. Neat PLA and plasticized PLA with the same thermomechanical history were considered for comparison. Nanocomposites based on amorphous PLA were obtained via melt-quenching. The influence of both plasticization and nanoparticle filling on the physicochemical properties of the nanocomposites were investigated. Characterization of the systems was achieved by size exclusion chromatography (SEC), thermogravimetric analysis (TGA), thermally modulated differential scanning calorimetry (TMDSC), X-ray diffraction (XRD), and dynamic mechanical analysis (DMTA). SEC revealed a decrease of the molecular weight of the PLA matrix with the filler content. Thermal behavior on heating showed one cold crystallization process in the reference neat PLA sample, while two cold crystallization processes in plasticized PLA and plasticized nanocomposites. The thermal windows of these processes tend to increase with the filler content. The crystalline form of PLA developed upon heating was affected neither by the plasticization nor by the type and content of Cloisite used. It was found that the series of organo-modified montmorillonites with decreasing affinity to PLA is Cloisite® 30B, Cloisite® 20A, and Cloisite® 25A, respectively. The dynamic mechanical properties were sensitive to the sample composition. Generally, the storage modulus increased with the filler content. Glassy PEG, well dispersed within unfilled PLA matrix, exhibited also a reinforcing effect, since the storage modulus of this sample was higher than for unplasticized reference at temperature region below the glass transition of PEG. Moreover, loss modulus of all plasticized samples revealed an additional maximum ascribed to the glass transition of PEG–rich dispersed phase, indicating partial miscibility of organic components of the systems investigated. The magnitude of this mechanical loss was correlated with the filler content, and to some extent, also with the nanofiller ability to be intercalated by polymer components. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 299–311, 2006
Role of sarcolemmal and mitochondrial KATP channels and EDHF‐mediated relaxation in coronary microarteries

To investigate the role of mitochondrial KATP (mitoKATP) channels in potassium channel opener (KCO)‐induced relaxation and its relationship with the endothelium‐derived hyperpolarizing factor (EDHF)‐mediated relaxation, isometric force was measured in porcine coronary microarteries (100–400 µm) mounted in a four‐channel myograph. In the rings precontracted with U46619 (−8 logM), in the presence of glibenclamide (GBC, 3 µM) or 5‐hydroxydecanoate (5‐HD, 100 µM), concentration–relaxation curves for KRN4884 or diazoxide were established. The EDHF‐mediated relaxation was induced by bradykinin (BK) in the presence of indomethacin (Indo), NG‐nitro‐L‐arginine (L‐NNA), and oxyhemoglobin (HbO). Both KRN4884 and diazoxide caused concentration‐dependent but endothelium‐independent relaxations. GBC but not 5‐HD inhibited these relaxations with increased EC50s (P<0.001). The EDHF‐mediated relaxation was unaffected by either GBC or 5‐HD but was reduced by the large and small conductance Ca2+‐activated K+ channel (KCa) blocker charybdotoxin and apamin. Thus, both KRN4884 and diazoxide cause endothelium‐independent vasorelaxation through opening sarcoKATP channels. While KCa channels play a role in mediating the EDHF‐mediated relaxation, neither sarcoKATP nor mitoKATP channels are likely involved in this vasculature. Drug Dev. Res. 58:90–95, 2003. © 2003 Wiley‐Liss, Inc.
Influence of microplate material on the sensitivity of growth inhibition tests with bacteria assessing toxic organic substances in water and waste water

In conjunction with aquatic bioassays, the effect of microplate (MP) material on the sensitivity of a cell multiplication inhibition test with luminescent bacteria (as representatives for unicellular organisms) was examined. The tested substances were four organic chemicals of different hydrophobic properties (4‐nitrotoluene, 3,5‐dichlorophenol, 2‐chloroaniline, sodium phenolate) and waste water from a chemical production plant. The study revealed, that (except for sodium phenolate) the toxic response to the testing material was influenced by the MP material. The employment of the common plastic MP led to an underestimation of the biotests results. Therefore it must be taken into consideration, that when using the microplate technique to expose unicellular organisms to toxic chemicals with hydrophobic properties, only MP made of quartz glass should be employed. ©1999 John Wiley & Sons, Inc. Environ Toxicol 14: 424–428, 1999
Extractability of Metal Sulfide Minerals in Acidic Solutions: Application to Environmental Studies of Trace Metal Contamination within Anoxic Sediments

Sulfide minerals are an important sink for metals within anoxic sediments. Extraction techniques using cold HCl to measure the concentration of sulfide mineral associated trace metals have gained wide acceptance as a proxy for potential metal bioavailability within the environmental community. However, certain metal sulfide phases that can potentially release metals into a more bioavailable phase do not extract in HCl. Laboratory experiments have shown that covellite (CuS), chalcocite (Cu2S), cinnabar (HgS), millerite (NiS), heazlewoodite (Ni2S3), and vaesite (NiS2) are poorly soluble in HCl; while greenockite (CdS), mackinawite (FeS1-x), pyrrohtite (FeS), galena (PbS), and sphalerite (ZnS) are highly soluble in HCl. Surface area can also affect the apparent solubility of CuS and NiS in HCl. These results indicate that use of HCl-based extraction schemes (e.g., AVS/SEM ratios) to assay sediments for metal contamination could underestimate the potential bioavailability of several metals of general interest.
Xanthan Gum and Alginate Based Controlled Release Theophylline Formulations

AbstractThe oral absorption of theophylline from two sustained release formulations, formulated using xanthan gum or sodium alginate, has been investigated in the beagle dog. A commercial product was used for comparison. Dissolution tests and an in vivo dog study both indicated that the xanthan gum tablet released drug at a constant rate and performed as a pH independent zero-order controlled release formulation. With the alginate tablet, faster dissolution rates were observed when acid medium was present. The pH dependent release behavior of the alginate formulation is explained. Drug release mechanisms which are influenced by the gel behaviors in these two polymers are discussed. The relative oral bioavailabilities of these two formulations in dog were 74–84% compared to immediately releasing capsules, and three-fold that of the commercial product with an equivalent dose.
Efficiency of Dry Matter and Nitrogen Accumulation and Redistribution in Wheat as Affected by Tillage and Nitrogen Management

Field experiments were conducted over 2 years with the hypothesis that farmyard manure (FYM), soybean residue (SR) as sole and/or in combination with urea under different tillage practices has similar effects on crop nitrogen (N) status and accumulation of dry matter (DM). Conventional ploughed plots had higher DM than other. Post anthesis accumulation of DM for minimum tillage (MT) was 4% higher than DT. Incorporation of 20 tons FYM ha−1 combined with 30 or 60 kg ha−1 had higher DM and N partitioned to leaves, stem, and spike than control. Leaves accumulated more DM at anthesis stage than other, whereas stem and spike at maturity than earlier stages. Fertilized plots had higher DM and N redistribution efficiency than control. However, N remobilization increased linearly with increasing DM accumulation (r2 = 22%). It was concluded that FYM coupled with N under MT showed marked variations for DM partition and N status in wheat than other treatments.
Structural evolution from mesoporous α-Fe2O3 to Fe3O4@C and γ-Fe2O3 nanospheres and their lithium storage performances

Mesoporous α-Fe2O3 nanospheres were synthesized through a solvothermal route, with polyethylene glycol as soft templates. The mesoporous nanospheres were then coated with carbon through hydrothermal treatment of glucose. After being calcined at 500 °C under Ar atmosphere for 4 h, mesoporous Fe3O4@C nanospheres were obtained. When further heated at 260 °C in air for 2 h, Fe3O4@C was transformed into γ-Fe2O3 mesoporous nanospheres. Significant phase changes occurred without destroying the structure of mesoporous nanospheres. All the three mesoporous nanospheres showed superior Li storage performances at the initial charge and discharge cycle; however, the cyclic stabilities of the three samples were quite different; Fe3O4@C exhibited a stable discharge capacity of ∼570 mA h g−1 after 30 cycles, while the discharge capacities of α-Fe2O3 and γ-Fe2O3 faded rapidly to ∼100 mA h g−1 after 30 cycles.
High resolution inductively coupled plasma mass spectrometry for the trace determination of plutonium isotopes and isotope ratios in environmental samples

A high resolution inductively coupled plasma mass spectrometric (HR-ICP-MS) method for the determination of plutonium isotopes and the 240 Pu/ 239 Pu isotope ratio utilising ultrasonic nebulisation was developed. Total plutonium concentrations ( 239+240 Pu) measured in environmental samples by this HR-ICP-MS method were in good agreement with data obtained from α-spectrometry. Quantification was performed by both external calibration and isotope dilution and the best agreement was found by applying isotope dilution. Detection limits of 5, 1 and 1 fg ml –1 were found for 239 Pu, 240 Pu and 242 Pu, respectively. These represent total amounts of 50, 10 and 10 fg or 0.1, 0.08 and 0.002 mBq of the three isotopes in a 10 ml sample volume. The precision (RSD) on the measurement of the 240 Pu/ 239 Pu ratio in environmental samples was approximately 2%, which is close to the theoretical precision (Poisson statistics). The influence of dwell time, number of sweeps and sample uptake rate on the measurement precision of the 240 Pu/ 239 Pu isotope ratio was investigated and the parameters were optimised using a 2 3 experimental design (a central composite design followed by a ridge analysis). The accuracy of the isotope ratio measurement was evaluated by comparing results from this HR-ICP-MS method with results from high resolution α-spectrometry and spectral deconvolution. Good agreement was found between the two techniques.
Adsorption Behaviour of Methylene Blue from Aqueous Solution on Poly(Ethylene Terephthalate)-g-4-Vinylpyridine/ 2-Hydroxyethylmethacrylate Fibers

Abstract In this study, a novel fibrous adsorbent obtained by grafting 4-vinyl pyridine (4-VP)/2-hydroxyethylmethacrylate (HEMA) comonomers onto poly (ethylene terephthalate) (PET) fibers was used for removal of methylene blue (MB) from aqueous solutions through a batch equilibration technique. The Influence of treatment time, pH of the solution, dye concentration, reaction temperature and percent graft yield on adsorbed amount were investigated. 300 min. of adsorption time was found sufficient to reach adsorption equilibrium for MB. It was found that the adsorption isotherm of MB fitted to Langmuir type isotherm. The highest adsorption capacity was found to be 55.33 mg MB per gram adsorbent. The adsorbed amount of MB was much higher on the comonomers grafted PET fibers than on the ungrafted PET fibers. MB was removed by 98 % while the initial dye concentration was at 5 mg L-1 and by 88% at 300 mg L-1 by monomers mixture grafted PET fibers. It was found that the reactive fibers were stable and regenerable by acid without loosing their activity.
Bilayer-induced asymmetric quantum Hall effect in epitaxial graphene

The transport properties of epitaxial graphene on SiC(0001) at quantizing magnetic fields are investigated. Devices patterned perpendicularly to SiC terraces clearly exhibit bilayer inclusions distributed along the substrate step edges. We show that the transport properties in the quantum Hall regime are heavily affected by the presence of bilayer inclusions, and observe a significant departure from the conventional quantum Hall characteristics. In particular, we observe anomalous values of the quantized resistance and a peculiar asymmetry with magnetic field which was not observed before for graphene on SiC. A quantitative model involving enhanced inter-channel scattering mediated by the presence of bilayer inclusions is presented that successfully explains the observed symmetry properties.
Transport of Lycopodium spores and other small particles to rough surfaces

Measurements have been made in the field and in a wind tunnel of the transport of Lycopodium spores to grass an d other surfaces, and wind tunnel experiments also have been done with aerosols of various smaller particle sizes. The spores and other particles were made radioactive to enable the deposition of small numbers on rough surfaces to be detected. In principle the experiments in the wind tunnel were similar to those previously done with gases (Chamberlain 1966), but the mechanisms by which particles and gases are transported across the boundary layer are different. The velocity of deposition vg of the particle to the surface is equal to the terminal velocity vs if the wind speed is very small, but at higher speeds deposition by impaction on roughness elements becomes progressively more important. If the roughness elements are of a form which gives good impaction efficiency, and have a sticky surface, vg is determined by the rate of eddy diffusion in the turbulent boundary layer above the surface, and may equal or even exceed the analogous velocity of deposition of momentum. The effect of surface texture and stickiness was investigated by comparing the catch of particles on segments of real leaves with the catch on similarity shaped segments of PVG treated with adhesive. Stickiness is important in determining vg for particles of about 10 μm diameter upwards, but not for smaller particles. In the field experiments, the use of radioactive tagging enabled the presence of a few Lycopodium spores in several grams of grass or soil to be detected, and the deposition could be measured at ranges up to 100 m from the source. At low wind speeds, vg was only a little greater than vs but at higher speeds the contribution of impaction became evident. A particularly high value was obtained when the grass was wet after recent rain. The field results with Lycopodium give a ratio of velocity of deposition to wind speed of 0·01, and this value is used to calculate the percentage of large spores or pollen grains which will travel various distances in normal meteorological conditions. It is found that the median range is about 1 km if the particles are liberated at a height of 50 cm, but 10 km if the height is 10 m. The relative importance of direct deposition to the ground and washout by rain of the air spora is considered, and is shown to depend on the effective height of the cloud of particles. For an effective height of 500 m, derived from vertical profiles of concentration observed from aircraft, it is calculated that about 25% of the total deposition of pollen grains may be in rain.
Solubility of Phenacetinum in Methanol, Ethanol, 1-Propanol, 1-Butanol, 1-Pentanol, Tetrahydrofuran, Ethyl Acetate, and Benzene between 282.65 K and 333.70 K

The solubility of phenacetinum in methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, tetrahydrofuran, ethyl acetate, and benzene was measured using a laser technique with a temperature range from 282.65 K to 333.70 K. The results of these measurements were correlated with a semiempirical equation.