Miracle-dz/UniFAR-FTUs huggingface dataset:
Effects of longitudinal quadrupoles on the phase behavior of a Gay-Berne fluid

The effects of longitudinal quadrupole moments on the formation of liquid crystalline phases are studied by means of constant NPT Monte Carlo simulation methods. The popular Gay–Berne model mesogen is used as the reference fluid, which displays the phase sequences isotropic-smectic A-smectic B and isotropic-smectic B at high (T*=2.0) and low (T*=1.5) temperatures, respectively. With increasing quadrupole magnitude the smectic phases are observed to be stabilized with respect to the isotropic liquid, while the smectic B is destabilized with respect to the smectic A. At the lower temperature, a sufficiently large quadrupole magnitude results in the injection of the smectic A phase into the phase sequence and the replacement of the smectic B phase by the tilted smectic J phase. The nematic phase is also injected into the phase sequence at both temperatures considered, and ultimately for sufficiently large quadrupole magnitudes no coherent layered structures were observed. The stabilization of the smectic A p.
Infrared and Electronic Spectra of Rare Earth Perovskites: Ortho-Chromites, -Manganites and -Ferrites

The electronic and ir spectra of rare earth perovskites of the general formula LnZO3, where Ln is the rare earth ion or yttrium and Z is Cr, Mn, or Fe, have been studied in detail. The results have been discussed in terms of crystallography, magnetic properties, covalency of Ln—O and Z—O bonds, and Goodenough's one electron energy diagrams. In all these compounds the rare earth ions do not markedly affect the electronic transitions of the transition metal ions; the 3d electrons clearly exhibit localized behavior. Both the electronic and ir spectra of the LnZO3 perovskites are comparable to the spectra of the corresponding transition metal sesquioxides, Z2O3.
Some novel aspects of dimerization of .alpha.-methylstyrene with acidic ion-exchange resins, clays and other acidic materials as catalysts

Influence des conditions experimentales et du solvant utilise sur la cinetique et la selectivite de la dimerisation de l'α-methyl styrene amorcee par des resines (Amberlyst, Nafion, Lewasorb) et des argiles traitees a l'acide. Proposition de conditions optimales pour la preparation de l'isomere industriellement important pour l'industrie (diphenyl-1,4 methyl-4 pentene-1)
Effects of Poloxamer Inhomogeneities on Micellization in Water

Pluronic P85 (poloxamer 235), which is a symmetrical PEO−PPO−PEO triblock copolymer of poly(ethylene oxide) and poly(propylene oxide), has been investigated by differential scanning calorimetry and chromatography. Interaction chromatography at critical conditions for PEO was used for chromatographic characterization and preparative separation of P85 according to PPO block lengths. The results show that the P85 sample is heterogeneous with respect to chemical composition and molar mass. P85 contains 12 wt % lower size impurities, which do not contribute to the main micellization transition. The shapes and widths of the micellization peaks observed in P85 thermograms are influenced by the distribution of PPO block lengths in P85, as shown from measurements on chromatographic fractions. PPO block lengths of the main P85 fraction follow a Poisson distribution closely. The characteristic temperatures of micellization, sphere-to-rod, and phase separation transitions observed in thermograms are influenced by pol.
THE ACCUMULATION IN SOIL OF CADMIUM RESIDUES FROM PHOSPHATE FERTILIZERS AND THEIR EFFECT ON THE CADMIUM CONTENT OF PLANTS

At least 80 percent of cadmium impurities in phosphate fertilizers applied during normal cropping practices could be accounted for in the cultivated layers of soils examined with the exception of a very light textured siliceous sand from which about 50 percent of the cadmium had been lost, possibly by leaching. Increases in zinc in these soils varied considerably because of substantial removal of zinc in farm produce and, in some cases, because of accession of zinc from sources other than fertilizers. Fertilizer impurities had increased the original levels of hydrochloric acid-soluble cadmium by more than 10-fold in several soils. In most cases the accumulated residues resulted in considerable increases in the cadmium content of plants grown both in glasshouse experiments and in the field, but radish (Raphanus sativus) grown on two soils which had been limed during the course of cultivation had lower cadmium contents than plants grown on the corresponding original unfertilized soils. This was in spite of substantial accumulation of cadmium in the cultivated soils and was probably due to higher soil pH brought about by liming. In a field experiment uptake by wheat of both native soil cadmium and cadmium residues from superphosphate was substantially increased by the application of ammonium nitrate. In glasshouse experiments uptake of cadmium from soil by plants was shown to be affected by soil pH, by the application of zinc, and by the level of soil phosphorus. Cadmium uptake was highest at low pH and decreased as pH was increased. The level of available phosphorus affected the cadmium content of subterranean clover through an effect on the transfer of cadmium from the roots to the plant tops but had little effect on the total uptake of cadmium. In terms of fertilizer application, however, the effects of phosphate and zinc on the cadmium content of plants would seem to be small compared with those resulting from the input of cadmium supplied as impurities in the fertilizers applied.
Double thermo-responsive hydrogels from poly(vinylcaprolactam) containing diblock and triblock copolymers

The thermally-induced gelation and gel properties of concentrated aqueous solutions of double thermoresponsive poly(N-vinylamide)-based di- and triblock copolymers are studied by rheology. The copolymers under investigation, prepared by cobalt-mediated radical polymerization and coupling reactions, are composed of poly(vinylcaprolactam) (PNVCL) blocks and of a statistical poly(vinylcaprolactam-stat-vinylpyrrolidone) segment with a cloud point temperature (TCP) higher than that of PNVCL. Heating the di- and triblock solutions beyond the first phase transition temperature favors gel formation while heating above the second TCP leads to opaque gels without macroscopic demixing. Moduli of the triblock hydrogels are systematically higher than those of the corresponding diblocks, even above the second transition. Rheological data suggest distinct micellar structures for each copolymer architecture: densely packed micelles of diblocks and 3-D networks of bridged micelles for triblocks. Strain sweep experiments also emphasize the positive effect of the micelle bridging on the elasticity and stability of the hydrogels. The formation and properties of the obtained gels are also shown to depend on the copolymer concentration, block length, and composition. Addition of salt also allows us to tune the phase transition temperatures of these double thermoresponsive hydrogels.
Polydopamine Formation In Poly (Vinyl Alcohol) + Montmorillonite Blends Allows To Produce Flexible And Robust Materials

It is demonstrated herein that the spontaneous oxidation of dopamine by dissolved oxygen (at pH = 9.6) in blends of poly(vinyl alcohol) and montmorillonite clay allows to produce robust stable and flexible sheets of material upon solvent casting and drying. The size of the membrane is only limited by the surface area of the collector vessel. In the absence of dopamine, and hence polydopamine, the deposit obtained in the same conditions undergoes cracks and does not form a material with the desired shape. Some structural characterizations of the PDA@PVA-MMT membranes and of the PVA-MMT blends are undertaken.
2-Phenyl­cyclo­hexyl 3-furan­carboxyl­ate

The crystal structure of the title compound, C17H18O3, contains mol­ecules that are separated by normal van der Waals distances. The cyclo­hexyl ring adopts a classical chair conformation, while the furan and phenyl rings are individually planar. The molecular dimensions are as expected.
A Performance Study of Optane Persistent Memory: From Indexing Data Structures’ Perspective

—In this paper, we study the performance of new Intel Optane DC Persistent Memory (Optane DC) from indexing data structures’ perspective. Different from existing Optane DC benchmark studies, which focus on either low-level memory accesses or high-level holistic system evaluations, we work on the data structures level, benchmarking commonly seen indexing data structures such as Linkedlist , Hashtable , Skiplist , and Trees under various running modes and settings. We believe that indexing data structures are basic and necessary building blocks of various real-world applications. Hence, the accurate knowledge about their performance characteristics on Optane DC will directly help developers design and implement their persistent applications. To conduct these performance evaluations, we implemented pmemids_bench , a benchmark suite that includes seven commonly used indexing data structures implemented in four persistent modes and four parallel modes. Through extensive evaluations on real Optane DC-based platform under different workloads, we identify seven observations that cover various aspects of Optane DC programming. These observations contani some unique results on how different data structures will be affected by Optane DC, providing useful reference for developers to design their persistent applications.
Qantitative determination of phase for macromolecular crystals using multiple diffraction methods and dynamical theory

Abstract Multiple diffraction techniques for quantitative phase determination of macromolecular crystals are briefly described and overviewed. The modified second-order iterative approximation [Chang, S. L. ; Tang, M. T. : Acta Cryst. A44 (1988) 1065] is employed to derive analytic expressions for the phase sensitivity of multiple diffraction and the visibility of multiple diffraction line profiles. Calculated visibility and sensitivity of three-beam cases of the protein, aldose reductase, are illustrated. The functions used for intensity profile fitting in the quantitative phase determination procedure are also modified accordingly. This calculation provides an effective way of choosing appropriate reflections for experimentally generating useful three-beam diffractions for phase analysis. Other practical issues are also addressed.
AN ISOTOPE DILUTION HIGH-RESOLUTION MASS SPECTROMETRY METHOD FOR QUANTITATIVE MEASUREMENT OF ISOMERIC BENZO[A]PYRENE TETROL METABOLITES DERIVED FROM ALBUMIN-BAPDE ADDUCTS AS INDICATORS OF HUMAN EXPOSURE TO POLYCYCLIC AROMATIC HYDROCARBONS

We evaluated in a pilot study a newly developed method of gas chromatography isotope dilution high-resolution mass spectrometry selected ion monitoring (GC-ID-HRMS-SIM). This method measures benzo[a]pyrene (B[a]P) tetrol metabolites released after albumin-BaPDE adduct hydrolysis. We isolated albumin adducts from the blood of a cohort of adult male and female smokers and nonsmokers randomly selected as exposed and nonexposed groups. Isomeric B[a]P tetrols released after adduct hydrolysis and silyl derivatization were quantified by GC-ID-HRMS-SIM using 13 C 6 -isotopically labeled BaP tetrol isomer standards (+/−)-BaP-r-7,t-8,t-9,c-10-tetrol (BPTI-1), (+/−)-BaP-r-7,t-8,t-9,t-10-tetrol (BPTI-2), (+/−)-BaP-r-7,t-8,c-9,t-10-tetrol (BPTII-1) and (+/−)-BaP-r-7,t-8,c-9,c-10-tetrol (BPTII-2). In all donor samples analyzed the method was sensitive enough to detect BPTII-1 and BPTI-1 in the low fmol range. In both smokers and nonsmokers BPTI-1 levels were higher than BPTII-1 levels. The mean levels of BPTII-1 and BPTI-1 in smokers were 0.16 ± 0.04 fmol/mg albumin (ranging from 0.09 to 0.28 fmol/mg albumin) and 0.40 ± 0.06 fmol/mg albumin (ranging from 0.25 to 0.75 fmol/mg albumin), respectively. The mean levels of BPTII-1 and BPTI-1 in nonsmokers were 0.22 ± 0.07 fmol/mg albumin (ranging from 0.09 to 0.41 fmol/mg albumin) and 0.47 ± 0.06 fmol/mg albumin (ranging from 0.30 to 0.75 fmol/mg albumin), respectively. The results from this study are the first reported quantitative levels of specific benzo[a]pyrene tetrol isomers detected by isotope dilution high-resolution mass spectrometry measurements of BaPDE-albumin adducts using 13 C 6 -isotopically labeled BaP tetrol isomer standards.
Zinc deficiency and oxidative stress in brain: magnetic resonance investigations in weanling rats

In humans, zinc deficiency is characterized by a broad spectrum of neurological clinical syndromes. It is known that vesicular zinc-enriched areas of the brain, such as the hippocampus, are responsive to zinc deprivation, which may result in learning impairment. Recent findings show that zinc deficiency may cause alterations in neurochemical activity. In this study we used contrast-enhanced magnetic resonance imaging (MRI) to monitor disruptions to the blood–brain barrier (BBB) and image-guided MR spectroscopy to follow alterations in brain metabolites as a result of zinc-deficiency and/or hyperoxia-induced oxidative stress. Gadolinium-diethylaminetriaminopentaacetic acid, an extracellular T1 relaxation contrast agent, increases tissue water signal in the brain if the BBB is damaged. A significant increase in postcontrast T1-weighted MR image intensity was observed in the brain of zinc-deficient or hyperoxia-exposed rats, as well as zinc-deficient rats exposed only to hyperoxia when compared with zinc-adequate rats. From single-voxel image-guided MR spectroscopy results, significant decreases in the ratio of N-acetyl aspartate, a neuronal-specific compound, to total choline levels were found when comparing controls (zinc-adequate or zinc pair-fed) with zinc-deficiency or hyperoxia groups alone, and when zinc-deficiency was combined with hyperoxia. This study demonstrates the sensitivity of MR techniques in the ability to monitor the effect of zinc deficiency combined with oxidative stress on BBB permeability as well as detect alterations in brain metabolites. This will further aid in our understanding of the possible cellular and molecular mechanisms involved in zinc deficiency pathology associated with the brain. J. Trace Elem. Exp. Med. 17:161–174, 2004. © 2004 Wiley-Liss, Inc.
COMPACTIBILITY OF CULTIVATED SPHAGNUM PEAT MATERIAL AND ITS INFLUENCE ON HYDROLOGIC CHARACTERISTICS

Deformation-stress-moisture relationships of cultivated sphagnum peat materials were studied in the laboratory using the Ottawa Texture Measuring System, an apparatus developed by Agriculture Canada. Impact of compaction on hydrologic characteristics was also investigated to determine the maximum stress which may be applied in the field during seed-bed preparation without limiting aeration for crop production. The study revealed that the compactibility of peat is relatively unaffected by moisture content at compactive pressure ≤13 kPa. However, under higher compactive pressure, the peat reaction was very similar to that of mineral soils, in which the compactibility increases with increasing moisture content until it reaches a maximum bulk density at saturation. The deformation-stress-moisture content relationships may be expressed by a simple third order polynomial equation. In response to compaction, the saturated hydraulic conductivity of the peat material reduced more than three orders of magnitude as bulk density increased from 0.1 to 0.25 g/cm3. A major increase in moisture retentivity was found in the compacted peat. Changes in hydrologic characteristics are primarily attributed to the reduction in large pores. Based on this information, it is concluded that compactive pressure exceeding 50 kPa may cause adverse effects on soil aeration.
Estudio de validación de las correlaciones para la fracción difusa de la irradiación solar en San Luis

C. Raichijk, A. Fasulo, H. Grossi Gallegos GERSolar, Instituto de Ecología y Desarrollo Sustentable (INEDES), Departamento de Ciencias Básicas, Universidad Nacional de Luján, Ruta 5 y Avda. Constitución, (6700) Luján, Buenos Aires, ARGENTINA, Tel. /Fax: (54-2323) 440241, E-mail: gersolar@mail.unlu. edu.ar 2 Dpto. de Física, Fac. de Cs. Físico Matemáticas y Naturales, Universidad Nacional de San Luis. Chacabuco y Pedernera, (5700) San Luis, ARGENTINA.
The electrical conductivity of single-crystal alumina

The electrical conductivity of alumina crystals with varying chromium content has been measured in air by a two-terminal d.c. method over the temperature range 20-850°C. When first heated all specimens showed peaks and pulses in the conduction current similar to those reported by Tucker and Gibbs for clear sapphire. After several heating and cooling cycles the variation of conductivity with temperature became reproducible with an activation energy averaging about 0.5 eV in the range 200-450°C and about 1.7 eV in the range 450-850°C. Conductivities at 850°C of 1 × 10-9 ohm-1 cm-1 for clear sapphire and of 2 × 10-10 ohm-1 cm-1 for pink ruby are compatible with the values obtained by Harrop and Creamer, but their suggestion that trace impurities of iron control the conductivity is not wholly substantiated.
Dimanganheptoxid zur selektiven Oxidation organischer Substrate

Des solutions de Mn 2 O 7 , dans CCl 4 ou le freon 113, oxydent les alcools primaires en acides carboxyliques, les alcools secondaires en cetones, les alcenes en acides carboxyliques et les ethers en esters (ou lactones) en milieu aprotique a basses temperatures
Modification of Calcium Phosphate Cement with α-Hydroxy Acids and Their Salts

Calcium phosphate cements (CPCs) are usually modified by organic/inorganic additives to improve their mechanical performance and to adjust their rheological and setting properties to clinical requirements. In this work we used several nontoxic and biocompatible α-hydroxylated organic acids (glycolic, lactic, malic, tartaric, and citric acids) and their calcium and sodium salts for the modification of CPC. The unmodified cement used in this study consisted of an equimolar powder mixture of tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) mixed with water at a powder mass/liquid volume ratio of 3.3 g/mL. It had a compressive strength of 38 MPa and an initial setting time of 8 min. The free acids as cement liquids had mainly a detrimental effect on the strength of the cement and led to a decreased setting time around 2−4 min, while the calcium salts did not significantly alter the cement properties. However, the sodium salts of the oligocarboxylic acids (malic, tartaric, and citric acid.
Poisson–Boltzmann for oppositely charged bodies: an explicit derivation

The interaction between two parallel charged plates in ionic solution is a general starting point for studying colloidal complexes. An intuitive expression of the pressure exerted on the plates is usually proposed, which includes an electrostatic plus an osmotic contribution. We present here an explicit and self-consistent derivation of this formula in the only framework of the Poisson–Boltzmann (PB) theory. We also show that, depending on external constraints, the correct thermodynamic potential can differ from the usual PB free energy. For asymmetric, oppositely charged plates, the resulting expression predicts a non-trivial equilibrium position with the plates separated by a finite distance. The depth of this energy minimum is decisive for the stability of the complex. It is therefore crucial to obtain its explicit dependence on the charge densities of the plates and on the ion concentration. Analytic expressions for the position and depth of the energy minimum were derived in 1975 by Ohshima [Colloid Polym. Sci. 253, 150 (1975)] but, surprisingly, these important results seem to have been overlooked. We retrieve these expressions in a simpler formalism, more familiar to the physics community, and give a physical interpretation of the observed behavior.
Capture of radioactive cations from water using niobate nanomaterials with layered and tunnel structures

Niobates with one-dimensional (1D) morphology, layered KNb3O8 nanorods and tunnel structured Na2Nb2O6·H2O nanofibers, are fabricated readily by a reaction between niobium oxide and alkali hydroxides under hydrothermal conditions. They exhibit ideal properties for removal of radioactive cations such as Sr2+, Ba2+ (as simulant for 226Ra2+) and Cs+ ions from wastewater through an ion exchange process. Compared with the Na2Nb2O6·H2O nanofibers, the KNb3O8 nanorods displayed better performance for the irreversible entrapment of the toxic cations, particularly Ba2+ cations, due to the deformation of the layer structure. Besides, these 1D niobates are acid resistant with selective uptake of the radioactive cations in the presence of a large excess of K+ or Na+ ions.
The cytoplasmic dynein motor complex at microtubule plus-ends and in long range motility of early endosomes, microtubule plus-end anchorage and processivity of cytoplasmic dynein

Cytoplasmic dynein is a microtubule-dependent motor protein which participates in numerous cellular processes. The motor complex consists of two heavy chains, intermediate, light intermediate and 3 families of light chains. Dynein is able to bind to these accessory chains as well as to regulatory proteins which enables the motor protein to fulfil such a variety of cellular processes. The associated light chains participate in long-distance organelle and vesicle transport in interphase and in chromosome segregation during mitosis. However, how these light chains control the activity of the motor protein is still unknown. In this study, I combine molecular genetics and live cell imaging to elucidate the role of the associated dynein light intermediate and light chains in dynein behaviour and early endosome (EE) motility in hyphal interphase cells as well as the anchorage of dynein to the microtubule (MT) plus-end in interphase and mitotic cells. I show that the dynein light intermediate chain (DLIC) as well as the light chain 2 (DLC2, Roadblock) are involved in dynein processivity and EE movement in interphase. The downregulation of either protein results in short hyphal growth which could be caused by a decreased runlength of EE and dynein. In addition, both proteins participate in dynein anchorage to the microtubule plus-end in interphase and mitosis as well as in spindle elongation during mitosis. Each protein causes a decrease of the motor protein dynein at MT plus-ends. Surprisingly, I found only minor or no defects in LC8 or Tctex mutants in the observed functions of dynein. LC8 seems to affect the dynein but not the EE runlength. In this case, dynein is still able to move into the bipolar MT array from where kinesin3 is able to take over EEs and move them towards the cell center. In contrast, Tctex has no effect on dynein or EE runlength or any other observed dynein function in hyphal cells. However, it causes a reduction in spindle
Removal of ruthenium from high-level radioactive liquid waste generated during reprocessing of spent fuel

AbstractRadio-ruthenium (Ru) due to its existence in the form of complexes with varied oxidation state, larger fission yield and relatively long half life is an extremely troublesome nuclide during reprocessing and subsequent waste management. In the process of the concentration of high-level waste (HLW), containing many nitrates of fission products and nitric acid, Ru is oxidised to volatile tetroxide RuO4, which is reduced to its dioxide (RuO2) at the inner surface of the equipment and is deposited there. As a result, the radiation dose of the plant equipments keeps increasing. A process was developed for the separation of Ru from HLW stream by volatilisation using KMnO4 (potassium permanganate) and O3 (ozone) as oxidising agent and its subsequent trapping on adsorbent material polyether ether ketone pellets. Various parameters like acidity, Ru concentration, temperature, time period of reaction and type of adsorbent were studied. The sorption behaviour was examined with various isotherms like Langmuir,.