Miracle-dz/UniFAR-FTUs huggingface dataset:
Debye Length and Double-Layer Forces in Polyelectrolyte Solutions

We report experimental results and a theoretical analysis of the Debye length in aqueous solutions of nonadsorbing polyelectrolytes. The measurements were done using a surface forces apparatus, in which the normal forces between smooth mica surfaces in aqueous hyaluronic acid (HA) solutions were measured as a function of surface separation (to ±1 A). HA is negatively charged and does not adsorb to the negatively charged surface of mica, as was established by optical and viscosity measurements and in agreement with the measured force−distance curves. From these measurements it appears that the multivalent polyelectrolyte is “depleted” from the gap between the surfaces. We use the mean-field Poisson−Boltzmann theory to theoretically predict the effective Debye length and double-layer force under such conditions and compare the predictions with the experimental results. The comparison gives excellent agreement and shows that the effective Debye length is determined solely by the monovalent ions in the soluti.
A General Chemical Conversion Route To Synthesize Various ZnO-Based Core/Shell Structures

Core/shell structures often exhibit improved physical and chemical properties. Developing a relatively general, facile, and low temperature synthetic approach for semiconductor core/shell structures with complex compositions is still a particularly challenging work. Here we report a general chemical conversion route to prepare high quality ZnO-based core/shell (ZnO/ZnS, ZnO/Ag2S, and ZnO/CuS) microspheres using inexpensive and commercially available reagents. The key to the success of our strategy lies in the use of reactive templates to realize the synthesis of various ZnO-based core/shell structures. The yielded core/shell nanostructures were confirmed by transmission electron microscopy, energy-dispersive X-ray analysis, and X-ray diffraction measurements. Photoluminescence of the ZnO/ZnS core/shell microspheres exhibits a distinct enhancement compared with that of the uncoated ZnO microspheres, showing potential application in optoelectronic devices such as ultraviolet light-emitting diodes and diode .
Novel Polymeric Nanoparticles Assembled by Metal Ion Addition

Potentially biodegradable graft polymer core-shell nanoparticles assembling by addition of metal ions intended to be used for radionuclide and drug delivery purposes are described. With Cu2+ ions, the self-assembly is slow (within minutes) with low efficiency. With Fe3+ ions the nanoparticles are formed immediately and are of convenient size for passive tumor accumulation by the enhanced permeation and retention effect. Full in vitro degradation of these particles is achieved with deferoxamine as a model of in vivo transchelation capacity.
Alteration of Kaolinite to Cancrinite and Sodalite by Simulated Hanford Tank Waste and its Impact on Cesium Retention

Caustic nuclear wastes have leaked from tanks at the US Department of Energy’s Hanford site in Washington State (USA) causing hundreds of thousands of gallons of waste fluids to migrate into the underlying sediments. In this study, four simulant tank waste (STW) solutions, which are high in NaOH (1.4 and 2.8 mol/kg), NaNO3 (3.7 mol/kg) and NaAlO2 (0.125 and 0.25 mol/kg), were prepared and reacted with reference kaolinite KGa-1 and KGa-2 at 50 and 80°C for up to 2 months. The structure and morphology of the resulting products were characterized using X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. The products were also examined for cation exchange and Cs+ sorption as a function of ionic strength and types of cations in the background solutions. Cancrinite and sodalite were the only new minerals observed in all of the conditions tested in this experiment. Two major chemical processes were involved in the reactions: dissolution of kaolinite and precipitation of cancrinite and sodalite. Increasing NaOH concentration and temperature, and decreasing NaAlO2 concentration increased the transformation rate. Both cancrinite and sodalite appeared stable thermodynamically under the experimental conditions. The newly formed feldspathoids were vulnerable to acid attack and pronounced dissolution occurred at pH below 5.5. Cancrinite and sodalite can incorporate NaNO3 ion pairs in their cages or channels. Sodium in cancrinite and sodalite was readily exchangeable by K+, but less easily by Cs+ or Ca2+. The feldspathoid products sorb nearly an order of magnitude more Cs+ than the unaltered kaolinite. The Cs adsorption is reduced by competing cations in the background solutions. At low ionic strength (0.01 M NaNO3 or 0.005 M Ca(NO3)2), Ca2+ was more competitive than Na+. When the concentration of the background solution was increased 10 times, Na+ was more competitive than Ca2+.
A real-space refinement procedure for proteins

This paper describes a procedure which optimizes the fitting of a `model' of a protein to an electron density map. The technique seeks to minimize ∫ (Qo−Qm)2dv where Qo is the observed electron density and Qm is a density associated with a model in terms of which the observed densities are interpreted. Qm consists of a Gaussian density centred on each atomic centre, and a floating background level. Interactions due to overlapping densities of neighbouring atoms are allowed for and the model is normally treated as a flexible chain so that bond lengths are conserved during movement. Alternatively, the atoms may be allowed to move independently. Site occupations and atomic radii are also refinable. The calculation is organized in terms of a `molten zone' of up to ten residues, which moves along the chain one residue at a time, linear or non-linear constraints being applied to preserve chain continuity at each end of the zone. Provision is made for the zone to become active or inactive in predetermined regions of the molecule. A difference map (Qo−Qm) is available at the end of the calculation, as is a molecular listing with revised coordinates and dihedral and inter-bond angles. Inter-bond angles may be treated either as constants or as variables, and if variable may be made elastically stiffer than dihedral angles. The procedure is well suited to maps of 2 to 3 A resolution, but is not limited to this range. It has produced convergent shifts exceeding 1.5 A in a map of 2 A resolution, and, except for shifts exceeding 1 A, convergence is essentially complete in one pass. The procedure has, so far, been applied to four proteins.
Synthesis, and Structural Characterization of [{CH3(C5H4N)}Ga(SCH2(CO)O)2] −[(4-MepyH)]+, A Novel Ga(III) Five-Coordinate Complex

The synthesis and structural characterization of a novel ionic Ga(III) five-coordinate complex [{CH3(C5H4N)}Ga(SCH2(CO)O)2]−[(4-MepyH)]+, (4-Mepy=CH3(C5H5N)) from the reaction between Ga2Cl4 with sodium mercapto-acetic acid in 4-methylpyridine is described. Under basic reaction conditions the mercapto ligand is found to behave as a 2e− bidentate ligand. Single crystal X-ray diffraction studies show the complex to have a distorted square-pyramidal geometry with the [(−SCH2(CO)CO−)] ligands trans. The compound crystallizes in the P21/c (No. 14) space group with a=7.7413(6)Å, b=16.744(2)Å, c=14.459(2)Å, V,=1987.1(6)&Aringsup3;, R(F, o)=0.032 and RW =0.038.
Ueber die Hydrazine der Brenztraubensäure

Die Hydrazine vereinigen sich ahnlich dem Hydroxylamin mit den Ketonen unter Abspaltung von Wasser. Einige der einfachen Verbindungen sind bereits von Hrn. Reisenegger1) beschrieben. Diese Reaktion ist, wie der Eine von uns1) schon angedeutet, und wie jetzt durch eine Reihe von Arbeiten im hiesigen Laboratorium festgestellt ist, ebenso allgemein, wie man es fur das Hydroxylamin durch die schonen Untersuchungen von Victor Meyer erfahren hat; sie gilt fur die primaren und sekundaren Hydrazine der fetten und aromatischen Gruppe und in gleicher Weise fur alle einfachen und den grossten Theil der complicirteren Ketone und Diketone. Besonders schon und ausgezeichnet durch ihre merkwurdigen Umwandlungen sind die betreffenden Verbindungen der Ketonsauren, welche ausserordentlich leicht beim Vermischen der Sauren und Hydrazine in neutraler oder saurer Losung entstehen und von denen wir zunachst die Verbindungen der Brenztraubensaure mit dem Phenyl- und Methylphenylhydrazin ausfuhrlicher untersucht haben.
DEP-FFF: Field-Flow Fractionation Using Non-Uniform Electric Fields

Dielectrophoresis (DEP) - the movement of particles in non-uniform electric fields - can be used in combination with Field Flow Fractionation (FFF) to separate particles with differing dielectric properties. An introduction is given to the technique of DEP-FFF and its application to the separation of cells and other particles. The separation of yeast cells using the subtechniques of steric and hyperlayer DEP-FFF is demonstrated. It is shown that the hyperlayer-DEP-FFF techniques have a number of advantages, including an improved separation efficiency and reduced adhesion to chamber walls. The hyperlayer-DEP-FFF separation technique is also independent of particle size and allows the use of higher medium conductivities than for conventional DEP methods.
Ammonium 2,6-dicarboxy-4-nitrophenolate

The title compound, NH4+·C8H4NO7− consists of a 2,6-dicarboxy-4-nitrophenolate anion and an ammonium cation, both of which possess crystallographic twofold rotation symmetry. All the O atoms of the anion and the H atoms of the cation contribute to hydrogen bonds, forming a three-dimensional network.
New optical probe designs for absolute (self-calibrating) NIR tissue hemoglobin measurements

Most of the instruments reported for near infrared absorption measurements in highly scattering media, suitable for noninvasive hemoglobin concentration measurements in living tissues, require some type of instrumental calibration, or knowledge of the initial concentrations of the two species. A new type of probe, which does not require calibration, has been developed. These new probes can provide a rapid and OabsoluteO measurement of absorption and scattering in tissue when combined with the Omulti-distanceO method developed, in part, at the Laboratory for Fluorescence Dynamics at the University of Illinois and ISS Incorporated. An initial evaluation of the performance and efficacy of these new probes has been performed using a frequency-domain ISS tissue oximeter. The new probes offer the convenience of not requiring calibration, and also provide more reliable measurements and greater long-term stability compared with the standard multidistance design. The new probes rely on a symmetrical arrangement of light sources and detectors. These geometries allow for measurements that are, in theory, entirely independent of the intensity differences between light sources, phase differences between the multiple light sources, sensitivity differences between the detectors, and any optical coupling losses, including those at the probe sample interface.
Effects of Injection and Surface Applications of Liquid Swine Manure on Corn Yield and Soil Composition 1

A 3-year field experiment was conducted to study the agronomic effects of methods and rates of liquid swine manure application to Brookston-Crosby silt loam soil (fine, mixed mesic Aeric Ochraqualfs) cropped to corn (Zea mays L.). Swine manure (5.2–6.6% dry matter) from an anaerobic pit was applied to soil annually at 90, 135, and 180 t/ha by injection (30 cm below soil surface) and broadcast (surface) methods. These three rates provided averages of 428, 643, and 857 kg N/ha; 133, 200, and 266 kg P/ha; and 155, 232, and 310 kg K/ha per year; respectively. Check and inorganic fertilizer (168 kg N/ha, 56 kg P/ha, and 112 kg K/ha) treatments were also studied. The injection method of liquid manure application increased corn grain yield an average of 2,130 kg/ha each year, compared with the broadcast method at similar rates of application. Injection of swine manure was associated with higher corn-leaf N levels the first year; corn-leaf N, P, and K levels the second year; and corn-leaf N and K the third year of the study when compared with corn leaves from the broadcast method. Rate of manure application had little influence on corn-leaf analyses, and inconsistent effects on corn yield. Nutrient loadings of the soil from liquid manure applications were in excess of crop requirements, as evidenced by nutrient accumulations, particularly P and K, in the soil. Increases in soil nutrient levels at different depths in the profile reflected the initial placement of the manure by application methods (broadcast vs. injection). Volatile losses of NH₃-N from surface-applied liquid manure were reflected in lower corn yield response, lower corn-leaf N content, and lower soil NH₄⁺ and NO₃⁻ levels when comparing these parameters with the injection treatment. Application of liquid swine manure by injection at the 90 t/ha rate increased corn grain yield 14% above that from the inorganic fertilizer treatment.
SHELF LIFE OF WHEY PROTEIN-COATED PISTACHIO KERNEL (PISTACIA VERA L.)

Dried pistachio kernels were coated with whey protein concentrate (WPC)/glycerol (Gly) solutions. Accelerated rancidity tests of uncoated and coated nuts were performed. Lipid oxidation in pistachios results in “flavor-fade” and off-flavor development. WPC-based coatings are excellent oxygen barriers and have the potential to be formed as coatings on pistachio kernels to extend their shelf life. Thus, I hypothesized that whey protein isolate films formed as coatings on pistachios would reduce the rate of peanut lipid oxidation. The objectives of this study were to determine coated and uncoated pistachio kernels' oxidation in pistachios stored at ambient conditions. Nine different formulations of WPC-based coatings were used to coat the pistachios. Besides an uncoated pistachio kernel reference, controls were used to investigate the effects of other ingredients in the coating formulation. The pistachio samples were stored in duplicate at ambient conditions for up to 24 weeks and then analyzed peroxide value (PV) and sensory properties. The objective of this work was to evaluate how WPC/lipid-based edible coatings affect the development of rancidity. Products resulting from lipid oxidation were measured by PV as an indicator of the formation of hydroperoxide, the primary initial product of lipid oxidation. The results indicate that the coated samples were oxidized significantly slower than the reference (uncoated pistachios); hence, the predicted shelf life is longer for the coated samples. The control samples also showed a delay in oxidation. The results also indicate that the WPC coatings, regardless of composition or thickness, provided a glossy appearance that made the coated nuts very distinctive from the uncoated nuts. In addition, coated nuts were slightly darker. PRACTICAL APPLICATIONS Edible films and coatings add value to their products, increase shelf life and/or reduce packaging. Applications of interest to the food industry include: 1 coating oxygen-sensitive foods such as nuts to extend shelf life and reduce packaging; 2 coating nuts to prevent oil migration into surrounding food components (e.g., nuts in chocolate).
Volume phase transition in a nonionic gel

Nonionic N‐isopropylacrylamide gel was found to undergo a discontinuous phase transition by changing a solvent composition or temperature. The observation that polymer gel with and without charge can undergo a first order volume phase transition is an evidence for the universality of the phase transition of polymer gels.
Caracterización y mecanismo de acción de diferentes moduladores de la Ca2+-ATPasa de membrana plasmática

La combinación de herramientas bioquímicas, biofísicas y moleculares han permitido profundizar en el estudio de la relación estructura-función de diversas proteínas. La Ca-ATPasa de membrana plasmática, enzima clave en el mantenimiento de la homeóstasis de Ca, es una proteína cuya función es altamente regulada. En este sentido, la CaATPasa es regulada por calmodulina, fosforilación por proteínas quinasas dependientes de AMPc y Ca, fosfolípìdos acídicos, proteólisis por calpaína, solventes orgánicos, etanol y segundos mensajeros de naturaleza lipídica como: diacilglicerol y esfingolípidos. El efecto de los distintos moduladores sobre la Ca-ATPasa ha sido caracterizado a nivel funcional y los sitios de interacción con la proteína han sido establecidos en algunos casos por estudios de inmunomarcaje y proteólisis. Recientemente con la disponibilidad de las herramientas moleculares se ha profundizado en el estudio de los sitios en la proteína donde intervienen cada uno de los compuestos que conocemos tienen un papel regulatorio sobre la enzima, pudiéndose establecer una relación entre las funciones y propiedades regulatorias de los moduladores y la estructura de la proteína. Por otra parte, hemos podido expresar y realizar manipulaciones genéticas de la enzima, pudiendo así profundizar sobre los mecanismos de acción de estos moduladores sobre la Ca-ATPasa de membrana plasmática.
Study of Fouling of a Cation Exchange Membrane with a Surfactant Using Voltamperometry

The purpose of the present work is to provide further information on concentration polarization and fouling of a Cation Exchange Membrane (CEM). This is undertaken by means of the voltamperometry technique to yield the characteristics of current-voltage curves. The deduced data of the limiting current density (LCD) and transmembrane resistances are discussed with respect to the concentration, mass, and charge of the counter-ion. Three graphical methods are used to determine the values of the LCD. They are, namely, Cowan-Brown, Derivative and Cross section of tangents methods. The fouling of the CEM is made in evidence using the foulant cationic surfactant Hexadecyltrimethylammonium chloride (CTAC). The values of the LCD and resistances show that the effect of this foulant is more pronounced on CEM than AEM, as a result of the signs of their functional groups.
Wannier function analysis for understanding disordered structures generated using Car-Parrinello molecular dynamics

Maximally-localized Wannier functions are used to investigate the structure and bonding details in an amorphous boron nitride network generated using Car-Parrinello molecular dynamics. The location of Wannier function centers (WFCs) provides a means of reliably determining the existence of a bond and its type between atoms. In addition, defect states such as lone pairs of electrons can be directly observed. The use of Wannier Functions for the analysis of networks is considerably more reliable than the "coordination shell" approach, where bonding statistics strongly depend on the particular choice of radius.
Assembly of Mesoscale Particles over Large Areas and Its Application in Fabricating Tunable Optical Filters

This paper describes a method for the crystallization of mesoscale particles over areas as large as ∼1 cm2. We injected an aqueous dispersion of spherical particles into a cell formed by two glass substrates and a square frame of photoresist that had been patterned on the surface of one of the substrates. One side of the frame had channels on its surface that could retain the particles while letting the solvent flow through. External gas pressure and sonication drove the particles into a cubic-close-packed (ccp) assembly with the (111) face parallel to the surfaces of the glass substrates. The smallest particles that have been crystallized by this method are polystyrene beads of ∼60 nm in diameter. The procedure presented here offers a number of attractive features: (i) It is relatively fast. For example, polystyrene beads of 0.48 μm in diameter can be crystallized into a 25 layer assembly over an area of ∼1 cm2 in ∼48 h. (ii) It has a tight control over the surface morphology and the number of layers of.
Distance Measurements by Dipolar Recoupling Two-Dimensional Solid-State NMR

We present a two-dimensional NMR technique for the measurement of dipolar couplings in polycrystalline solids. This experiment is fully transverse and uses a windowless dipolar recoupling pulse sequence (DRAWS, described in Gregory, D. M.; et al. Chem. Phys. Lett. 1995, 246, 654−663) to effect coherence transfer. Direct, internuclear coherence transfer produces negative cross-peaks in the 2D spectrum. Cross-peak development and experimental requirements for obtaining distances from the two-dimensional solid-state NMR spectra of two- and three-spin systems are discussed, and demonstrations are shown for thymidine-2,4-13C2 and l-alanine-13C3. Internuclear distances are derived by comparison of experimental cross-peak buildup curves with numerical simulations. In the three-spin system, indirect coherence-transfer mechanisms prohibit the interpretation of buildup curves as due to isolated spin pair interactions and limit the accuracy of some distance measurements. This 2D technique can also be used for spectr.
Selenium uptake and its antioxidant role in ryegrass cultivars as affected by selenite seed pelletization

Abstract A greenhouse study was carried out to evaluate the effect of seed pelletization with increasing selenite doses (from 0 to 60 g Se ha -1 ) on the yield, Se uptake and the an-tioxidant responses of three ryegrass cultivars (Aries, Nui and Quartet) cultivated on an Andisol during two consecutive growth periods. In addition, a second assay was conducted to determine the residual effect of Se in the shoots during four consecutive plant cuts. Results showed that selenite-pelleted seeds at rates up to 60 g Se ha -1 did not influence the yield of shoots and roots of the three ryegrass cultivars. Selenium concentration in shoots and roots steadily increased as a consequence of increased Se supply, and it was accumulated mainly in the roots. Plants of the different cultivars accumulated similar amounts of Se in their shoots, but Quartet roots built up greater Se concentration than those of Aries or Nui at rates of application above 35 g Se ha -1 . Whereas Se doses above 10 g ha -1 increased the shoot Se concentration in the two yields of the three ryegrass cultivars to suitable levels according to the minimum dietary requirement of beef and dairy cattle, the residual effect of Se was maintained through four cuts at Se supply of 30 and 60 g ha
Polyaddition behavior of bis(five‐ and six‐membered cyclic carbonate)s with diamine

Polyadditions of 1,2-bis[3-(1,3-dioxan-2-one-5-yl)-propylthio]ethane (B6CC) and 1,2-bis[4-(1,3-dioxolan-2-one-4-yl)-butylthio]ethane (B5CC) with 4,9-dioxadodecane-1,12-diamine were carried out. The reactivity of B6CC with the diamine was higher than that of B5CC. Additionally, B6CC gave a higher molecular weight polymer than B5CC. The reaction-rate constants of B6CC and B5CC at 30, 50, and 70 °C were evaluated as 0.70, 0.89, and 1.07 L/mol · h; and 0.03, 0.06, and 0.10 L/mol · h in N,N-dimethylacetamide (initial reagent concentration 0.5 M), respectively. The activation energies were estimated to be 9.2 and 24.9 kJ/mol in the reactions of B6CC and B5CC with the diamine, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 860–867, 2001