A Study of the Potential Use of Red Mud to Obtain Compositions Based on Portland Cement

The paper deals with the problem of utilization of red mud which is a waste product from alumina production using the Bayer method. The principal possible use for the red mud of JSC “Bogoslovsky aluminum plant” (Sverdlovsk region) for the compositions based on Portland cement is shown. It was found that the mud introduction accelerates beginning of the cement paste setting and thickens the paste reducing its mobility. It is concluded that the introduction of red mud up to 30 % is justified in terms of strength indicators. The work is carried out using mathematical planning of experiments. Keywords: red mud, Portland cement, active mineral additive, composition, properties, bauxite, chemical composition, cement stone strength, mathematical planning of experiment

Granite Dust is the Possible Component of the Dry Construction Mixtures

This paper is devoted to research of possibility of utilization of granite dust. It is shownthat the granite dust from the crushing screenings of "Shartashskiy stone-crushed stone quarry" can be recommended as a filler for the production of dry building mixes for flooring. With the introduction of dust in the amount of 20 % by weight of cement it is possible to obtain the mortar of the class not less B12.5. Keywords: Granite dust, dust-like waste, Portland cement, polymer, modification, compressive strength, flexural strength, sand, dry mixture, mortar, compositio

Feasibility Study for a Neutron-Based Investigation of Polymer Cement Concretes

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The Impact of the Functional Layer Composition of Glucose Test-Strips on the Stability of Electrochemical Response

Herein, the impact of the chemical stability of RedOx mediator ferricyanide, K3 [Fe(CN)6 ] (FC), a type of buffer solution used for bioreceptor preparation, gel composition (carboxymethylcellulose, CMC, Aerosile, AS, and alginate, ALG) on the long term stability of glucose test-strips and their analytical performance was examined. By simple addition of ALG to the functional gel aiming to improve its viscosity, we managed to enhance the sensitivity of conventional CMC-containing amperometric glucose test-strips from 3.3 µA/mM to 3.9 µA/mM and extend their shelf life from 8 months to 1.7 years. Moreover, during the course of investigations, it was revealed that the activity of enzyme in dependence with the used buffer did not linearly correlate with its activity in a dried functional layer, and the entire long-term electrochemical signal of glucose test-strips was determined by RedOx mediator FC chemical stability. The most stable and sensitive test-strips were obtained by the screen-printing approach from a gel containing 24 mg/mL GOx prepared in citrate buffer with pH 6, 200 mg/mL of FC and 10 mg/mL of CMC supplemented with 25 mg/mL of ALG

Nitrogen-containing compounds of Kazakhstan petroleum vacuum gas oil

Relevance. The need to accumulate data on nitrogen-containing compounds of heavy fractions, the share of which in secondary oil refining is steadily increasing every year. With the weight of raw materials the amount of sulfur-, nitrogen- and oxygen-containing components in it increases. The high content of heteroatomic compounds has a negative impact on catalytic processing, the quality and performance characteristics of the products obtained, and the environment. One of the widespread processes for upgrading crude oil, in particular, vacuum gas oil, is hydrotreating. However, during the catalytic hydrodesulfurization of heavy distillates the reactions of hydrogenolysis of organic sulfur compounds are inhibited in the presence of nitrogen-containing compounds. At the same time, the degree of hydrodenitrogenation of heavy oil fractions is relatively low. It is known that petroleum nitrogen-containing compounds are divided into nitrogenous bases titrated with acid solutions and nonbasic nitrogen compounds. Nitrogenous bases are represented mainly by alkylbenzo- and alkylnaphthenobenzo derivatives of pyridine. Nonbasic compounds may include benzologs of pyrrole and amides. Determining the composition of nitrogen-containing compounds in vacuum gas oil and studying their transformations during hydrotreatment is an important and actual problem. Aim. Comparative study of high- and low-molecular nitrogenous bases and nonbasic nitrogen-containing compounds of vacuum gas oil of Kazakhstan oil before and after hydrotreating. Objects. Samples taken before and after the catalytic hydrotreatment of vacuum gas oil from Kazakhstan oil. Methods. Hydrotreatment, elemental analysis, potentiometric titration, benzene cryoscopy, IR and 1H NMR spectroscopy, structural group analysis. Results. The paper introduces a comparative characteristic of the composition and structure of high and low molecular weight nitrogenous bases from the original and hydrotreated vacuum gas oil. Under the conditions of hydrotreatment, the total removal of nitrogen was 6.56 wt %, and the content of Nbas. decreased by 36%. At the same time, nitrogenous bases in the hydrotreated product are characterized by low molecular weights. Using IR spectroscopy, similar structural fragments were identified in the nitrogen compounds of the original and hydrotreated vacuum gas oil: pyridine rings (1573–1574 cm–1), carboxylic (3209–3225 and 1701–1709 cm–1) and sulfoxide (1032–1033 cm–1) groups. Among the nitrogen-containing compounds of the original vacuum gas oil, amides (1647–1648 cm–1) were identified, which are absent in the composition of nitrogen-containing compounds of the hydrotreated vacuum gas oil. Hydrocarbon skeletons of molecules include aromatic (1599–1602 cm–1) and aliphatic fragments (2860–2960 and 1454–1460, 1377, 723–727 cm–1). In accordance with the results of the structural group analysis, the averaged molecules of high and low molecular weight nitrogenous bases of the original and hydrotreated vacuum gas oil are represented by naphthenoaromatic structures with different alkyl framing. The differences observed between the values of individual structural parameters of the nitrogenous bases average molecules of the original and hydrotreated vacuum gas oil may indicate the compounds transformations under study during hydrotreatment

New records of lichens and allied fungi from the Leningrad Region, Russia. VIII

Thirteen species and one variety of lichens, nine lichenicolous and two saprobic fungi are reported for the first time for St. Petersburg, the whole Leningrad Region or its western or eastern parts. The lichens Bacidina brandii, B. neosquamulosa, Porina leptalea, Rinodina aspersa and the lichenicolous fungus Scutula dedicata are reported for the first time for Russia, lichenicolous fungus Lichenoconium aeruginosum – for European Russia, the lichen Tetramelas chloroleucus, lichenicolous fungi Lichenoconium pyxidatae and Tremella cetrariicola are new for the North-Western European Russia. The most interesting records are briefly discussed.

Switching ion binding selectivity of thiacalix[4]arene monocrowns at liquid–liquid and 2D-confined interfaces

Understanding the interaction of ions with organic receptors in confined space is of fundamental importance and could advance nanoelectronics and sensor design. In this work, metal ion complexation of conformationally varied thiacalix[4]monocrowns bearing lower-rim hydroxy (type I), dodecyloxy (type II), or methoxy (type III) fragments was evaluated. At the liquid–liquid interface, alkylated thiacalixcrowns-5(6) selectively extract alkali metal ions according to the induced-fit concept, whereas crown-4 receptors were ineffective due to distortion of the crown-ether cavity, as predicted by quantum-chemical calculations. In type-I ligands, alkali-metal ion extraction by the solvent-accessible crown-ether cavity was prevented, which resulted in competitive Ag+ extraction by sulfide bridges. Surprisingly, amphiphilic type-I/II conjugates moderately extracted other metal ions, which was attributed to calixarene aggregation in salt aqueous phase and supported by dynamic light scattering measurements. Cation–monolayer interactions at the air–water interface were monitored by surface pressure/potential measurements and UV/visible reflection–absorption spectroscopy. Topology-varied selectivity was evidenced, towards Sr2+ (crown-4), K+ (crown-5), and Ag+ (crown-6) in type-I receptors and Na+ (crown-4), Ca2+ (crown-5), and Cs+ (crown-6) in type-II receptors. Nuclear magnetic resonance and electronic absorption spectroscopy revealed exocyclic coordination in type-I ligands and cation–π interactions in type-II ligands

A global look at time: a 24-country study of the equivalence of the Zimbardo Time Perspective Inventory

In this article, we assess the structural equivalence of the Zimbardo Time Perspective Inventory (ZTPI) across 26 samples from 24 countries (N = 12,200). The ZTPI is proven to be a valid and reliable index of individual differences in time perspective across five temporal categories: Past Negative, Past Positive, Present Fatalistic, Present Hedonistic, and Future. We obtained evidence for invariance of 36 items (out of 56) and also the five-factor structure of ZTPI across 23 countries. The short ZTPI scales are reliable for country-level analysis, whereas we recommend the use of the full scales for individual-level analysis. The short version of ZTPI will further promote integration of research in the time perspective domain in relation to many different psycho-social processes

Formation of the Russian Siberian Identity in the Wood Engravings of the Krasnoyarsk Craftsmen

This article concerns such a topical modern problem as a loss of identity by the Russian citizens in general and by the residents of the Krasnoyarsk region in particular. Nowadays, the uniqueness of the Siberian character, local nature and life in the Siberian region is perceived differently from the way it was perceived in the past. Influence of the western cultures which change ideas about traditions, norms and values is becoming very significant. As never before, the regional culture of the Krasnoyarsk region needs models, which can vividly illustrate Siberian identity, inspire Siberian self-awareness and evoke pride for the small motherland. Work of arts, which have deep ideas and meanings in their present sensuous form, may become such models. As an example to prove this assumption we considered such a type of fine art as graphics and its form - xylography. From the graphical work of arts, which take part in the formation of the Siberian identity, the works of the Siberian school of xylography by Herman Pashtov have been chosen. The target of their analysis is to identify the mental characteristics of Siberia and Siberians, whose viewers can perceive by looking at xylography. The methodological base consists of the theoretical abstracts of the modern theory of fine art and development of the theory of art critics. As the result of their analysis it was discovered that in the works of the Krasnoyarsk craftsmen of the Siberian school of xylography, the images of Siberia in different manifestations (the city, nature, people, relationships, etc.) illustrate ideas, which contribute to the formation of the Siberian identity.В настоящей статье уделяется внимание такой актуальной проблеме современности, как утрата идентичности жителями России вообще и жителями Красноярского края в частности. Уникальность сибирского характера, местной природы, жизни в Сибирском регионе стала восприниматься совершенно иначе, чем в прошлом. Слишком активно стало инокультурное влияние западных стран, изменяя в обществе представления о традициях, нормах, ценностях. Как никогда раньше региональная культура Красноярского края стала нуждаться в эталонах, способных наглядно продемонстрировать сибирскую идентичность, пробудить самосознание людей в качестве сибиряков, вызвать чувство гордости за свою малую Родину. Такими эталонами могут выступать произведения искусства, несущие в своей чувственно-явленной форме глубокие идеи и смыслы. В качестве примера, доказывающего данную гипотезу, был взят такой вид изобразительного искусства, как графика, и его разновидность - ксилография. Из графических произведений искусства, участвующих в процессах формирования сибирской идентичности, были выбраны работы мастеров Сибирской школы ксилографии Германа Паштова. Цель их анализа - выявление ментальных характеристик Сибири, Красноярска, сибиряков, которые могут быть считаны зрителями из произведений. В качестве методологии использовались теоретические положения современной теории изобразительного искусства, а также разработки теории художественной критики. В результате их рассмотрения было выявлено, что в работах красноярских мастеров Сибирской школы ксилографии образы Сибири в различных ее проявлениях (город, природа, люди, отношения и т.д.) действительно демонстрируются идеи, способствующие формированию сибирской идентичности