Miracle-dz/UniFAR-FTUs huggingface dataset:
Sodium cis-bis­(imino­diacetato-κ3N,O,O′)­chromate(III) sesquihydrate

In the title compound, Na[Cr(C4H5NO4)2]·1.5H2O, the CrIII-centered complex anion displays an octahedral coordination geometry formed by two facial imino­di­acetate dianions, with two N atoms in a cis configuration. The Na+ ion is surrounded by one water and five carboxyl O atoms, with Na—O distances of 2.3221 (15)-2.5531 (18) A. There is an extensive hydrogen-bonding network in the crystal structure.
Quantitative Characterization of Humic Substances by Solid-State Carbon-13 Nuclear Magnetic Resonance

The compositions of humic acids (HAs) from various Histosols in North America and Europe, of similarly treated plant-extracted materials (PEMs), of coal-extracted humic acids, and of International Humic Substances Society (IHSS) Florida peat were quantified by solid-state 13 C nuclear magnetic resonance (NMR). In order to obtain quantitative intensities, the peak areas in direct-polarization 13-kHz magic-angle spinning (DPMAS) 13 C NMR spectra were corrected for incomplete relaxation by factors measured in cross-polarization spin-lattice relaxation time (CP/T 1 ) experiments with total sideband suppression (TOSS). The elemental compositions (%C, %H, %O + N) of a peat sample, 8 HAs and 2 PEMs were estimated from the NMR results and compared with chemical analyses, as well as solution NMR for two of the HAs. The results are in good agreement, which shows that DPMAS corrected by CP/T 1 -TOSS permits quantitative characterization of HAs and PEMs. The compositions of the PEMs deviate significantly from those of the Histosol HAs. The compositions in terms of nine types of chemical groups were computed. The investigated HAs consist of more than 60% of aromatic and CO carbons (including both carbonyl and carboxyl groups). Previous cross-polarization magic-angle spinning (CPMAS) NMR experiments have significantly underestimated the ratio of sp 2 -to sp 3 -carbons; in particular, the true COO carbon fraction is a factor of two larger than estimated by CPMAS NMR. In spite of their wide range of geographical origins, the compositions of the Histosol HAs appear to be relatively uniform, suggesting that the search for a general model of Histosol HA structure is worthwhile. Eight models proposed in the literature do not reproduce the experimentally determined compositions, but a few models show promising partial agreement.
FOCUS :N OVEL APPROACHES TO PEPTIDE AND PROTEIN STRUCTURE Evaluation and Optimization of Electron Capture Dissociation Efficiency in Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

Electron capture dissociation (ECD) efficiency has typically been lower than for other dissociation techniques. Here we characterize experimental factors that limit ECD and seek to improve its efficiency. Efficiency of precursor to product ion conversion was measured for a range of peptide (15% efficiency) and protein (33% efficiency) ions of differing sizes and charge states. Conversion of precursor ions to products depends on electron irradiation period and maximizes at 5–30 ms. The optimal irradiation period scales inversely with charge state. We demonstrate that reflection of electrons through the ICR cell is more efficient and robust than a single pass, because electrons can cool to the optimal energy for capture, which allows for a wide range of initial electron energy. Further, efficient ECD with reflected electrons requires only a short (500 s) irradiation period followed by an appropriate delay for cooling and interaction. Reflection of the electron beam results in electrons trapped in or near the ICR cell and thus requires a brief (50 s) purge for successful mass spectral acquisition. Further electron irradiation of refractory precursor ions did not result in further dissociation. Possibly the ion cloud and electron beam are misaligned radially, or the electron beam diameter may be smaller than that of the ion cloud such that remaining precursor ions do not overlap with the electron beam. Several ion manipulation techniques and use of a large, movable dispenser cathode reduce the possibility that misalignment of the ion and electron beams limits ECD efficiency. (J Am Soc Mass Spectrom 2005, 16, 1060 –1066) © 2005 American Society for Mass Spectrometry
Zero-Inflated Regression Models for Modeling the Effect of air Pollutants on Hospital Admissions

Count regression methods are the fundamental tool used for modeling the association between environmental pollution and hospital admissions. Data with many zeros are often encountered in count regression models. Failure to account for the extra zeros may result in biased parameter estimates and misleading inferences. Zero-inflated Poisson and zero-inflated negative binomial regression models have been proposed for situations where the data generating process results in too many zeros.
Sensitivity Analysis in Chemical Kinetics

Complex mathematical models are increasingly being used as predictive tools and as aids for understanding the processes underlying observed chemical phenomena. The parameters appearing in these models, which may include rate constants, activation energies, thermodynamic constants, transport coefficients, initial conditions, and operating conditions, are seldom known to high precision. Thus, the predictions or conclusions of modeling endeavors are usually subject to uncertainty. Furthermore, regardless of uncertainty questions, there is always the overriding matter of which parameters control laboratory observations. Quantification of the role of the parameters in the model predictions is the traditional realm of sensitivity analysis. A significant amount of current research is directed at conceptualization and implementation of numerical techniques for determining parametric sensitivities for algebraic, differential, and partial differential equation models including those with stochastic character and nonconstant parameters. Recent studies have also served to extend the range of the conventional parametric analysis to address new questions, relevant to the process of model building and interpretation. This review attempts to present a full range of results and applications of sensitivity analysis, relevant to chemical kinetic modeling. We exclude a large class of literature that deals with system sensitivities from a control theory perspective (1). We further limit discussion of related subjects such as parameter identification (estimation of best parameter values for fitting data) and optimization, in which parametric sensitivities play only
JP-900 Hydroperoxidation and Decomposition

JP-900 (C10H18) is a bicyclic, high-energy-density fuel being employed in aircrafts. In recent years, inspection of fuels refined by different processes has showed that no- ticeably higher peroxide concentrations exist in fuels, which have been severely hydrotreated. Hydroperoxide concentration was considered to be a parameter in fuel in- stability. Presently, Density functional theory (DFT) calcula- tions were carried out to investigate the mechanisms of ox- idation of JP-900 through hydroperoxidation. The total electronic energies of JP-900, and certain radicals and hy- droperoxides originated from JP-900 were calculated. Their thermodynamic stabilities were discussed. The most feasi- ble "carbon center" of JP-900 that would be oxidized through hydroperoxidation was assigned. It has been found that the hydroperoxides may decompose to different products having greater stability (possessing more negative total electronic energies). A variety of mechanisms includ- ing carboxylic acid (ester)-alkane, alcohol-aldehyde and ketone-alcohol decomposition mechanism were ques- tioned. The probable decomposition products were deter- mined and confirmed by thermodynamic calculations.
The effects of sample imperfections on optical spectra

The results of the theory of light reflection from rough surfaces have been extended to cover the case of light transmission through a sample with rough surfaces, as well as reflection and transmission for inhomogeneous samples. A concept of “Inhomogeneity Induced Roughness” of the constant phase plane has been introduced to describe the specular reflection from inhomogeneous media. The drastic influence of the multiple scattering effect on the optical spectra has been demonstrated for a simple model. The generalized formulae for reflection and transmission of light for imperfect samples are given. Finally, several peculiar experimental observations concerning exciton spectra in II–VI compounds, light scattering at the plasma frequency in metals, electroreflection, and other effects are discussed. Die Theorie der Lichtreflexion an rauhen Oberflachen wird fur den Fall der Lichttransmission durch eine Probe mit rauhen Oberflachen sowie der Reflexion und Transmission von nicht homogenen Proben erweitert. Der Begriff einer „Rauhheit durch Inhomogenitat” der konstanten Phasenflache wird eingefuhrt, um die Spiegelung an nichthomogenen Medien zu beschreiben. Der drastische Einflus der Vielfachstreuung auf die optischen Spektren wird an einem einfachen Modell erlautert. Es wird eine verallgemeinerte Formel fur die Reflexion und Transmission von Licht an unvollkommenen Proben angegeben. Gestutzt auf diese Vorstellungen wird eine Erklarung vorgeschlagen, um verschiedene, spezielle, experimentelle Beobachtungen auf dem Gebiet der Exzitonspektren von II–VI-Verbindungen, Lichtstreuung bei der Plasmafrequenz in Metallen, Elektroreflexion und anderer Effekte zu erklaren.
Preparation and Optical Properties of Colloidal, Monodisperse, and Highly Crystalline ITO Nanoparticles

Colloidal, monodisperse, highly crystalline ITO nanoparticles with various particle sizes and tin contents were prepared by a one-pot thermal decomposition of tin and indium precursors in oleylamine. The PL emission maxima become blue-shifted as the particle size decreases and the tin content increases.
Decolorization of aqueous solutions of disperse textile dyes by oxidoreductases

The potential of three oxidoreductases, a laccase preparation of Pleurotus sajor-caju PS-2001, horseradish peroxidase (HRP) and a microbial peroxidase (MP) was evaluated for the decolorization of disperse textile dyes (CI Disperse Red 343, CI Disperse Red 167 and CI Disperse Blue 148) used in polyester dyeing. Decolorization was studied in aqueous solutions varying in dye concentration, pH, temperature, enzyme concentration and the addition of mediators HBT and syringaldazine. The best conditions found for Disperse Red 343 with laccase, HRP and MP were: 15 mg L−1 dye concentration, 50°C, pH 3.0 for laccase and pH 5.0 for peroxidases. Without mediator, the highest decolorizaton results (38.5% and 58.6%) were achieved with the highest tested concentrations of laccase (10 U mL−1) and HRP (89.7 U mL−1), respectively, but no significant difference in decolorization was found for the tested MP concentrations (29.9–89.7 U mL‐1). HBT or syringaldazine increased decolorization with peroxidases significantly, but no effect was observed for the laccase. Decolorization of Disperse Red 167 (up to 15%) and Disperse Blue 148 (up to 25%) was much lower than of Disperse Red 343. With respect to enzyme concentration, the use of mediator and under the selected test conditions the laccase of P. sajor-caju PS-2001 turned out to be more efficient in disperse dye decolorization, than peroxidases HRP and MP.
Reservoir Modeling of Production of CH4 from Natural Gas Hydrates by Injection of a CO2+N2 Gas Mixture*

Natural gas hydrates are non-stoichiometric crystalline inclusion compounds are likely to contain more carbon than in all other fossil fuel reserves combined. Different techniques that are currently being proposed for production of CH4 from the gas hydrates include depressurization, thermal stimulation and injection of inhibitors (Sloan and Koh, 2007). These methods involve dissociation of gas hydrate and the release of a significant amount of water that may cause geomechanical stresses on the reservoir that could lead to subsidence. A newly proposed method is to replace CH4 in the hydrate by the injection of pure CO2 or CO2+N2 mixtures, which serves dual purpose of long-term storage of a greenhouse gas (CO2) and the production of natural gas, while maintaining the hydrate structure in situ (Ohgaki et al., 1996), thus making the operation carbon neutral.
Degradation of CI Reactive Red 141 by heterogeneous Fenton-like process over iron-containing ZSM-5 zeolites

The Fenton-like oxidation of CI Reactive Red 141 was investigated over iron-containing ZSM-5 zeolites. Iron was loaded by ion exchange or through hydrothermal synthesis. The oxidation process was carried out in an aqueous solution using hydrogen peroxide as the oxidant. The catalyst prepared by ion exchange with a silicon/aluminium ratio of 42 zeolite showed the highest activity (97% decolorisation and 52% chemical oxygen demand reduction at an initial pH of 3.5) after an oxidation duration of 2 h. The chemical oxygen demand reduction increased with the increasing amount of iron loaded to the zeolite. The FeZSM-5 catalyst, prepared by hydrothermal synthesis in the presence of oxalic acid, showed very good activity in terms of mineralisation (99% of chemical oxygen demand reduction). The iron leaching was noticeably low (below the European Union directives of 2 mg dm−3) for the above-mentioned catalysts.
Sulfate emissions from catalyst-equipped automobiles on the highway

The essential effect of the present results is to reinforce substantially the conclusions drawn earlier. H/sub 2/SO/sub 4/ from catalyst-equipped 49-state cars on the highway has still not developed into a serious problem, as of 1977, after 3 model-years of production. Sulfate concentrations in the tunnel are not greatly higher than ambient levels in spite of the lack of opportunity for atmospheric dispersion of the emissions. And even so, approx. 2/3 of the vehicle-generated SO/sub 4//sup -2/ in the tunnel still comes from the Diesel trucks, whose SO/sub 4//sup -2/ emission rates are considerable. Diesel cars may eventually appear in substantial numbers; their SO/sub 4//sup -2/ emission rates are currently approx. 10 mg/km, comparable to a catalyst-equipped gasoline powered car or approx. 1/3 that of a heavy-duty Diesel. It should be emphasized that the present results and conclusions would not necessarily apply in California (where different emission control technology exists) or in future years even at the present site (as emission standards and control systems continue to change).
Re‐investigation of preferential orientation of Cu(In,Ga)Se2 thin films grown by the three‐stage process

The present contribution deals with the rather longstanding issue of the preferential orientation of Cu(In,Ga)Se2 polycrystalline thin films. We investigate both the influence of the growth process parameters and that of the presence of Na on the competition between [112] and [220] orientations. The influence of the presence of Na is studied through the comparison of CIGSe layers co‐evaporated on our laboratory standard Mo‐coated soda lime glass (SLG/Mo) and on substrates with a sodium diffusion barrier (SLG/barrier/Mo); the process dependence of the orientation is evaluated through the comparison of films grown by the standard bithermal three‐stage (400–630°C) and the derived isothermal three‐stage process (620°C). For all the process/substrate combinations, the properties of the films (preferential orientation, grain size and morphology) have been determined at key steps of the growth. From these experimental results, it can be concluded that, as already suggested in the literature, the final layer orientation is strongly related to the texturation of the (In,Ga)2Se3 precursor; however, the amount of Na available when the film becomes Cu‐rich (recrystallization at the end of the 2nd‐stage) can also strongly impact the film orientation. Such a phenomenon is herein interpreted by mean of the grain boundary migration model of recrystallization. In agreement with this new interpretation of the experimental data, processes have been designed in order to grow [220] textured CIGSe layers. Copyright © 2011 John Wiley & Sons, Ltd.
Real‐time dynamics of clusters. I. I2Xn (n=1)

Vibrational predissociation of I_2X_n (X=Ne, Ar) van der Waals clusters are studied in real‐time using picosecond pump–probe (LIF) and molecular beam techniques. The state‐to‐state rates of vibrational predissociation are measured for specific vibrational levels v′_i by monitoring the rise of nascent I_2. Here, we report our study of I_2X(B,v′_i)k(v '_i,v′_f) →I_2(B,v′_f)+X. For I_2Ne, the values of τ=k^(−1)(v'_i,v′_f) decrease nonlinearly from 216 ps for v'_i=13 to 53 ps for v′_i=23. For I_2Ar (B,v'_i), which undergo electronic and vibrational predissociation, the risetime of the nascent I_2 is found to be 70 ps when v′_i=18 and 77 ps when v'_i=21. A number of theoretical models for vibrational predissociation (the energy‐gap law, the momentum‐gap law, quantum and classical calculations) are compared with our experimental results in an attempt to understand the key features of the dynamics and the potential energy surface.
Sol-Gel Derived Composite Ceramic Carbon Electrodes

Sol-gel electrochemistry is gaining popularity as a versatile general method for the production of inorganic-organic electrodes and electrochemical sensors. Carbon-ceramic electrodes constitute a fine example that demonstrates the disadvantages, capabilities and promise of sol-gel electrochemistry. The compositions, configurations and chemistry of carbon ceramic electrodes are reviewed. Application for diverse fields of electrochemistry, including electrochemical sensing, biosensing and energy storage cells are reviewed.
On the optical absorption of free polarons at weak coupling

The optical absorption of Frohlieh polarons as a function of the frequency of the incident light is calculated within the Lee‐Low‐Pines formalism. A simple calculation, which is developed here in full detail, gives a result for the absorption coefficient which is exact in order a. Gurevich et al. [1] had obtained this perturbation result using involved calculations based on Green's functions. This result is also extracted here from the “dissipation” calculation of Feynman ct al. [2]. An analytical expression for the optical absorption between 0 < α < 1 is proposed. For α = 1 the main correction to the perturbation result is e decrease of about 15% around the maximum of the absorption. This seems to explain the difference between the experimental absorption detected in CdO (α = 0.75) by Finkenrath et al. [14] and the perturbation result. The effect of a static electric field on the optical absorption coefficient is examined. For low temperatures a shift towards lower frequencies of the threshold for absorptiou is predicted. This shift depends on the mobility and effective mass of the polaron.
Sensitivity to guest–host force fields in adsorption equilibrium of cyclic hydrocarbons in one-dimensional molecular sieve

We have investigated the effect of different guest–host force fields (united atom, UA; all-atom, AA; and anisotropic united atom, AUA) on the adsorption of cyclic hydrocarbon molecules in AlPO4-5 molecular sieve. Grand canonical Monte Carlo (GCMC) simulations of benzene, xylene and cyclohexane adsorption and positioning are carried out. The results suggest that the force field choice affects considerably the positioning of benzene and cyclohexane molecules while xylenes presented a smaller sensibility. The force fields difference of sensibilities among cyclical molecules seems to be associated with the critical geometric condition identified by Yashonath and Santikary denominated levitation effect. In this condition, the net forces on the guest due to the host is at a minimum, the levitation ratio (γ) is close to unity and we have a weakly bound guest that can be easily moved from its balance position. Unlike xylene, that is only slightly affected by the choice of the force field, benzene and cyclohexane molecules in AlPO4-5 have such dimensions that result in levitation ratio (γ) close to unity. These results point out to the care that should be taken in the choice of the force field when the guest–host size ratio is near the value defined for the levitation effect.
Microbial Analyses of Cement and Grouting Additives

During sampling in the ONKALO tunnel in 2006, heavy growth of a slimy material was observed in connection with grouting. It was suggested to be microbial growth on organic additives leaching from the grout. Two sampling campaigns resulted in the isolation of several aerobic bacterial strains. Some of these strains were used in biodegradation studies of three solid cement powders, eight liquid grout additives, and six plastic drainage materials. Degradation was also studied using ONKALO groundwaters as inoculums. The isolated strains were most closely related to hydrocarbon-degrading microorganisms. The biodegradation of seven of the products was tested using microorganisms isolated from the ONKALO slime in 2006; none of these strains could degrade the tested products. When ONKALO drillhole groundwaters were used as inoculums in the degradation studies, it was demonstrated that Structuro 111X, Mighty 150, and Super-Parmix supported growth of the groundwater microorganisms. Structuro 111X is a polycarboxylate condensate while Mighty 150 and Super-Parmix are condensates with formaldehyde and naphthalene. Some of the isolated microorganisms belonged to the genus Pseudomonas, many strains of which can degrade organic molecules. None of the plastic drainage materials supported growth during the degradation studies. Microorganisms were present in two of the liquid products when delivered, GroutAid and Super-Parmix. The potential of the organic compounds in grout additives to be degraded by microorganisms, increasing the risk of biofilm formation and complexing compound production, must be considered. Microbial growth will also increase the possibility of hydrogen sulphide formation.
Temperature- and pH-responsive properties of poly(vinylidene fluoride) membranes functionalized by blending microgels

A novel blend membrane with temperature- and pH-responsive properties was prepared by the physical blending of poly(vinylidene fluoride) (PVDF) bulk material, poly(N-isopropylacrylamide) (PNIPAAm) microgels and poly(acrylic acid) (PAA) microgels with a simple and practical procedure, which is suitable for industrial scale production. The composition and structure of the blend membrane were investigated by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and field-emission scanning electron microscope (FESEM). The results indicated that the incorporation of PAA and PNIPAAm microgels improved the pore size, porosity and hydrophilicity of the blended membrane, leading to a higher water flux and remarkable antifouling property. In particular, the blend membrane exhibited temperature- and pH-sensitive characteristics. The dual responsive feature makes it easy to control the blend membrane’s rejection properties as well as the water flux and helps the membrane retain preferable mass transfer and separation property when responding to one of the investigated stimuli.