Influence of the coking properties of coal batch on coke properties

At OAO Zapadno-Sibirskii Metallurgicheskii Kombinat (ZSMK), research is undertaken to improve the optimization of coking batch. The basic approach, proposed by specialists from OAO Nizhne-tagil’skii Metallurgicheskii Kombinat, employs the coefficient K _opt, which characterizes the deviation of the batch from its optimal composition. The coking properties of the OAO ZSMK coal batch over the last few years are analyzed. After laboratory and industrial coking of batch with different K _opt, the strength and reactivity of the resulting coke is investigated. Evaluation of coke-grade coal in terms of its rank according to State Standard GOST 25543-88 proves inadequate, since coal of the same rank may differ markedly in coking properties. A method is established for assessing the optimality of the coal batch at OAO ZSMK.     

New phases in Fe−Nd alloys obtained by quenching from the liquid state

Conclusions In alloys of the Fe–Nd system obtained by quenching from the liquid state, we observe the following phases: for (28–58)% Fe–P₁ (T_C240°C); for <28% Fe–P₂ [T_C=(220±5)°C]. In the alloy based on Nd containing 5% Co and 23% Fe, we observe the P₃ phase with T_C=160°C (tentatively amorphous).The presence of the P₁ phase in Nd-(37–58)% Fe alloys is responsible for the increase in the coercive force_IH_C up to 0.4 MA/m. During annealing, the amount of P₁ phase is reduced, a stable Nd₂Fe₁₇ phase appears, which is accompanied by a sharp decrease in the coercive force. In the alloy based on Nd containing 5% Co and 23% Fe, after annealing the P₄ phase is formed (T_C=340°C, H_a4.8 MA/m), which causes the appearance of the coercive force_IH_C=1.52 MA/m.Moscow Institute of Steel and Alloys. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 9, pp. 13–16, September, 1992.     

Simulation of low-energy argon ion scattering from surface copper clusters

The scattering of normally incident 200-eV Ar⁺ ions from individual clusters consisting of 13 and 39 copper atoms on a (0001) graphite surface was simulated by the molecular dynamics method. The angular distribution of scattered argon ions and their energies and reflection coefficients are discussed.     

Novel Anti-Neuroinflammatory Properties of a Thiosemicarbazone–Pyridylhydrazone Copper(II) Complex

Neuroinflammation has a major role in several brain disorders including Alzheimer’s disease (AD), yet at present there are no effective anti-neuroinflammatory therapeutics available. Copper(II) complexes of bis(thiosemicarbazones) (Cu^II(gtsm) and Cu^II(atsm)) have broad therapeutic actions in preclinical models of neurodegeneration, with Cu^II(atsm) demonstrating beneficial outcomes on neuroinflammatory markers in vitro and in vivo. These findings suggest that copper(II) complexes could be harnessed as a new approach to modulate immune function in neurodegenerative diseases. In this study, we examined the anti-neuroinflammatory action of several low-molecular-weight, charge-neutral and lipophilic copper(II) complexes. Our analysis revealed that one compound, a thiosemicarbazone–pyridylhydrazone copper(II) complex (CuL⁵), delivered copper into cells in vitro and increased the concentration of copper in the brain in vivo. In a primary murine microglia culture, CuL⁵ was shown to decrease secretion of pro-inflammatory cytokine macrophage chemoattractant protein 1 (MCP-1) and expression of tumor necrosis factor alpha (Tnf), increase expression of metallothionein (Mt1), and modulate expression of Alzheimer’s disease-associated risk genes, Trem2 and Cd33. CuL⁵ also improved the phagocytic function of microglia in vitro. In 5xFAD model AD mice, treatment with CuL⁵ led to an improved performance in a spatial working memory test, while, interestingly, increased accumulation of amyloid plaques in treated mice. These findings demonstrate that CuL⁵ can induce anti-neuroinflammatory effects in vitro and provide selective benefit in vivo. The outcomes provide further support for the development of copper-based compounds to modulate neuroinflammation in brain diseases.     

Kinetics of terbium oxide film growth from Tb(dpm)3 vapor

We have studied the kinetics of terbium oxide chemical vapor deposition using the Tb(dpm)₃ complex. At substrate temperatures in the range 465–560°C, films ranging in thickness from 25 to 360 nm have been obtained. At precursor partial pressures below 13 Pa in an argon atmosphere, the films had smooth surfaces with separate islands. Higher precursor pressures led to the formation of dense island films. At deposition temperatures in the range 465–560°C, the process was found to switch from kinetically limited, with an effective activation energy of 190 ± 15 kJ/mol, to adsorption-limited, with an activation energy of 38 ± 5 kJ/mol. The order of the reaction with respect to the precursor was determined to be 0.8.     

Oxidation kinetics of chromium in fine-particle TiO<Subscript>2</Subscript>-Cr<Subscript>2</Subscript>O<Subscript>3</Subscript> Oxides

The mass transport during the oxidation of Cr₂O₃ in mixtures of fine-particle TiO₂ and Cr₂O₃ in air has been studied at temperatures from 800 to 1000°C by magnetochemical analysis. The results indicate that the process leads to the oxidation of up to ten surface atomic layers. The mass transport is shown to be a stochastic, steplike process.     

Regular Physical Exercise Modulates Iron Homeostasis in the 5xFAD Mouse Model of Alzheimer’s Disease

Dysregulation of brain iron metabolism is one of the pathological features of aging and Alzheimer’s disease (AD), a neurodegenerative disease characterized by progressive memory loss and cognitive impairment. While physical inactivity is one of the risk factors for AD and regular exercise improves cognitive function and reduces pathology associated with AD, the underlying mechanisms remain unclear. The purpose of the study is to explore the effect of regular physical exercise on modulation of iron homeostasis in the brain and periphery of the 5xFAD mouse model of AD. By using inductively coupled plasma mass spectrometry and a variety of biochemical techniques, we measured total iron content and level of proteins essential in iron homeostasis in the brain and skeletal muscles of sedentary and exercised mice. Long-term voluntary running induced redistribution of iron resulted in altered iron metabolism and trafficking in the brain and increased iron content in skeletal muscle. Exercise reduced levels of cortical hepcidin, a key regulator of iron homeostasis, coupled with interleukin-6 (IL-6) decrease in cortex and plasma. We propose that regular exercise induces a reduction of hepcidin in the brain, possibly via the IL-6/STAT3/JAK1 pathway. These findings indicate that regular exercise modulates iron homeostasis in both wild-type and AD mice.     

Redox processes in fine-particle TiO<Subscript>2</Subscript>-Cr<Subscript>2</Subscript>O<Subscript>3</Subscript> oxides

We have studied the stability of the Cr⁶⁺ ion in fine-particle TiO₂-Cr₂O₃ oxides during storage after calcination in air. The results indicate that, during storage under normal conditions for 720 days, Cr⁶⁺ is reduced to Cr³⁺. The redox process is due to partial surface hydration of the Cr₂O₃ and TiO₂ crystallites.