Admittance of CdS nanowires embedded in porous alumina template

CdSnanowires of 10nm diameter, electrodeposited in porous alumina films, had shown a conductance bistability in the past [Appl. Phys. Lett.76, 460 (2000)]. The conductance has a high (ON) and a low (OFF) state. In the ON state, different sets of nanowires display qualitatively different relation between the conductance and capacitance. We propose a model to explain this anomalous behavior. Based on this model, we predict that the inelastic mean free path of electrons in the nanowires is 3–3.5nm at room temperature. This short mean free path may be a consequence of acoustic phonon confinement

Proposed model for bistability in nanowire nonvolatile memory

Cadmium sulfide nanowires of 10‐nm diameter, electrodeposited in porous anodic alumina films, exhibit an electronic bistability that can be harnessed for nonvolatile memory. The current–voltage characteristics of the wires show two stable conductance states that are well separated (conductances differ by more than four orders of magnitude) and long lived (longevity\u3e1 yr at room temperature). These two states can encode binary bits 0 and 1. It is possible to switch between them by varying the voltage across the wires, thus “writing” data. Transport behavior of this system has been investigated at different temperatures in an effort to understand the origin of bistability, and a model is presented to explain the observed features. Based on this model, we estimate that about 40 trapped electrons per nanowire are responsible for the bistability

Solution calorimetry as a complementary tool for the determination of enthalpies of vaporization and sublimation of low volatile compounds at 298.15 K

In this work a new solution-based calorimetry approach for determination of the sublimation and vaporization enthalpies of low volatile compounds was proposed. The approach is based on the measurement of solution enthalpy of a molecule of interest in benzene and as well as the measurement of molar refraction index for this molecule. Enthalpies of solution at infinite dilution in benzene for a set of 18 aromatic and polyaromatic hydrocarbons were measured at 298.15 K. Experimental data on vaporization/sublimation enthalpies for this set were collected from the literature. For validation of the literature data additional sublimation experiments were performed for phenanthrene, 1-phenylnaphthalene, 1,2-diphenylbenzene, 1,2,3,4-tetraphenylnaphthalene, hexaphenylbenzene, and rubrene using transpiration, quartz crystal microbalance, and thermogravimetry. Vaporization/sublimation enthalpies derived from the solution calorimetry approach were in good agreement (within experimental uncertainties) with those measured by conventional methods. The solution-based calorimetry approach gives a reliable and quick appraisal of vaporization/sublimation enthalpies. This approach constitutes a complementary additional thermochemical option for vaporization/sublimation enthalpies data evaluation as well as for rapid data gathering for low volatile and/or thermally unstable organic compounds. © 2014 Elsevier B.V

Joint Thermal Treatment of Heavy Oil and Liquid Products of Fast Wood Pyrolysis for Producing Fuels and Chemicals

© 2017, Springer Science+Business Media, LLC, part of Springer Nature. Joint thermal treatment of heavy oil and liquid products of fast wood pyrolysis is investigated. Thermal analysis shows that the coke yield does not increase if the liquid products are added up to 20 mass%. The liquid wood-pyrolysis products decompose much earlier than heavy oil. However, the decomposition of the blends is essentially the same as pure-oil decomposition

Structure-property relationships in ionic liquids: Influence of branched and cyclic groups on vaporization enthalpies of imidazolium-based ILs

© 2015 Elsevier Ltd. Ionic liquids (ILs) with branched and cyclic substituents are seldom studied in the literature, and as such there are little to no data characterizing their thermophysical properties. ILs with branched and cyclic substituents are just as convenient to synthesize and study as their counterparts with linear substituents, but the effects of these substituents on IL properties are not yet well-defined due to the preference for linear substituents. Standard molar vaporization enthalpies of six imidazolium based ionic liquids [Rmim][NTf2] with iso-alkyl and cyclic substituents (R = iso-propyl, iso-butyl, sec-butyl, methylcyclopropyl, cyclopentyl and methylcyclohexyl) were derived from quartz-crystal microbalance (QCM) method. Enthalpies of vaporization measured at elevated temperatures have been adjusted to the reference temperature 298 K and tested for consistency by comparison with the homomorphy alkane, alkylbenzenes and alkyl-imidazoles. It was found that vaporization enthalpies of ILs with the iso-alkyl and cyclic groups are generally on the same level within (±2 to 3) kJ · mol-1 significantly compared to the analogous ILs with the imidazolium cation substituted with the linear alkyl substituents of the same chain length. These findings are useful for the quick estimation of vaporization enthalpies of various substituted IL cations (e.g. pyrrolidinium, ammonium, pyridinium, etc.)

Corundum Molds for Investment Casting from Refractory Alloys and Metals

Production procedure, physical-chemical, and performance properties of ALUMOX silica-free binder used for the production of high-heat-resistant corundum shell molds by consumable patterns employed in the production of critical molds from superalloyed reactive metals and alloys are described. ALUMOX usage allows obtaining casts from reactive metals and alloys with surface roughness up to 60 m), which, in its turn, increases fatigue parameters of the material (endurance, durability)

Thermodynamic properties of myo-inositol

© 2017 Elsevier Ltd In the present work, the temperature dependence of heat capacity of vitamin B8 (myo-inositol) has been measured for the first time over the range from 8 K to 340 K by precision adiabatic vacuum calorimetry. Based on the experimental data, the thermodynamic functions of the vitamin B8, namely, the heat capacity, enthalpy H°(T)–H°(0), entropy S°(T)–S°(0) and Gibbs function G°(T)–H°(0) have been determined for the range from T → 0 K to 340 K. The value of the fractal dimension D in the function of multifractal generalization of Debye's theory of the heat capacity of solids was estimated and the character of heterodynamics of structure was detected. The enthalpy of combustion (−2747.0 ± 2.1) kJ·mol−1 of the vitamin B8 was measured for the first time using high-precision combustion calorimeter. The standard molar enthalpy of formation in the crystalline state (−1329.3 ± 2.3) kJ·mol−1 of B8 at 298.15 K was derived from the combustion experiments. Using combination of the adiabatic and combustion calorimetry results the thermodynamic functions of formation of the myo-inositol at T = 298.15 K and p = 0.1 MPa have been calculated. The low-temperature X-ray diffraction was used for the determination of coefficients of thermal expansion

Thermal analysis and calorimetric study of the combustion of hydrolytic wood lignin and products of its pyrolysis

© 2015 Springer Science+Business Media New York. Thermal decomposition of hydrolyzed lignin is studied in the 300-700°C range in an inert gas atmosphere. The yields of solid, liquid, and gaseous decomposition products are determined. It is demonstrated by combustion calorimetry that the carbonaceous residue of lignin pyrolysis has the highest calorific value. The calorific value of the carbonaceous residue of pyrolysis resin is higher than that of the original lignin. It is shown by thermogravimetry and differential scanning calorimetry with mass spectrometric detection of gases that lignin and its thermal decomposition products could undergo thermolysis with formation of various volatile compounds. Thermal decomposition starts at roughly the same temperature and is 320°C. The loss of sample mass increases in the following sequence: carbonaceous residue < lignin < liquid fraction

Regulation of caspase-3 processing by cIAP2 controls the switch between pro-inflammatory activation and cell death in microglia.

Cell Death and Disease is an open-access journal published by Nature Publishing Group. This work is licensed under a Creative Commons Attribution 4.0 International Licence. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons licence, users will need to obtain permission from the licence holder to reproduce the material.The activation of microglia, resident immune cells of the central nervous system, and inflammation-mediated neurotoxicity are typical features of neurodegenerative diseases, for example, Alzheimer's and Parkinson's diseases. An unexpected role of caspase-3, commonly known to have executioner role for apoptosis, was uncovered in the microglia activation process. A central question emerging from this finding is what prevents caspase-3 during the microglia activation from killing those cells? Caspase-3 activation occurs as a two-step process, where the zymogen is first cleaved by upstream caspases, such as caspase-8, to form intermediate, yet still active, p19/p12 complex; thereafter, autocatalytic processing generates the fully mature p17/p12 form of the enzyme. Here, we show that the induction of cellular inhibitor of apoptosis protein 2 (cIAP2) expression upon microglia activation prevents the conversion of caspase-3 p19 subunit to p17 subunit and is responsible for restraining caspase-3 in terms of activity and subcellular localization. We demonstrate that counteracting the repressive effect of cIAP2 on caspase-3 activation, using small interfering RNA targeting cIAP2 or a SMAC mimetic such as the BV6 compound, reduced the pro-inflammatory activation of microglia cells and promoted their death. We propose that the different caspase-3 functions in microglia, and potentially other cell types, reside in the active caspase-3 complexes formed. These results also could indicate cIAP2 as a possible therapeutic target to modulate microglia pro-inflammatory activation and associated neurotoxicity observed in neurodegenerative disorders

Molecular determinants of Smac mimetic induced degradation of cIAP1 and cIAP2

The inhibitors of apoptosis (IAP) proteins cIAP1 and cIAP2 have recently emerged as key ubiquitin-E3 ligases regulating innate immunity and cell survival. Much of our knowledge of these IAPs stems from studies using pharmacological inhibitors of IAPs, dubbed Smac mimetics (SMs). Although SMs stimulate auto-ubiquitylation and degradation of cIAPs, little is known about the molecular determinants through which SMs activate the E3 activities of cIAPs. In this study, we find that SM-induced rapid degradation of cIAPs requires binding to tumour necrosis factor (TNF) receptor-associated factor 2 (TRAF2). Moreover, our data reveal an unexpected difference between cIAP1 and cIAP2. Although SM-induced degradation of cIAP1 does not require cIAP2, degradation of cIAP2 critically depends on the presence of cIAP1. In addition, degradation of cIAP2 also requires the ability of the cIAP2 RING finger to dimerise and to bind to E2s. This has important implications because SM-mediated degradation of cIAP1 causes non-canonical activation of NF-κB, which results in the induction of cIAP2 gene expression. In the absence of cIAP1, de novo synthesised cIAP2 is resistant to the SM and suppresses TNFα killing. Furthermore, the cIAP2-MALT1 oncogene, which lacks cIAP2's RING, is resistant to SM treatment. The identification of mechanisms through which cancer cells resist SM treatment will help to improve combination therapies aimed at enhancing treatment response