Stress-Strain Behavior of Crushed Concrete as a Special Anthropogenic Soil.

The stress-plastic dilatancy relationship was investigated for crushed concrete during drained and undrained triaxial compression tests in the light of the frictional state concept. The slope of the dilatant failure state line is greater than that of quartz sand for drained triaxial compression due to the crushing effect. The crushing effect parameters for drained and undrained conditions are very similar.

Effect of a Fine Fraction on Dynamic Properties of Recycled Concrete Aggregate as a Special Anthropogenic Soil.

The literature confirms that fine recycled concrete aggregate (fRCA) can be used as a replacement for natural soil in new concrete, offering many advantages. Despite these advantages, there are also critical barriers to the development of fRCA in new mixes. Among these, the first challenge is the variability of fRCA properties, in both physical, chemical, and mechanical terms.

Perspective on the Application of Machine Learning Algorithms for Flow Parameter Estimation in Recycled Concrete Aggregate.

The constantly expanding civilization and construction industry pose new challenges for a sustainable development economy. Aiming to protect the environment is often associated with waste management, thereby reducing the number of landfills. The management of recycled concrete aggregate (RCA) from building demolition and its reuse in construction perfectly fits into this trend.

Magnetic cooling: a molecular perspective.

The magnetocaloriceffect is considered as an energy-efficient and environmentally friendly technique which can take cooling technology to the next level. Apart from its commercial application at room temperature, magnetic refrigeration is an up-and-coming solution for the cryogenic regime, especially as an alternative to He systems. Molecular magnets reveal advantageous features for ultra-low cooling which are competitive with intermetallic and lanthanide alloys.

Effect of Dispersed Reinforcement on Ultrasonic Pulse Velocity in Stabilized Soil.

One of the fundamental techniques for road subgrades is soil stabilization. Considering the high emission of carbon dioxide during the production of binders, novel techniques to reduce the binder are being studied. Thus, we investigated dispersed reinforcement in stabilized soils.

Geotechnical and Environmental Assessment of Blast Furnace Slag for Engineering Applications.

The increasing demand for building materials in the road industry creates interest for a new source of high-quality aggregates. In order to conserve natural resources, more attention is focused on anthropogenic soils and industrial solid wastes. For the successful application of these types of soil, a series of geotechnical and environmental tests have to be conducted.

Influence of Dispersed Reinforcement on Mechanical Properties of Stabilized Soil.

Stabilized soils are commonly used as part of pavement construction in highway engineering. The everyday use of this material makes it necessary to classify it. One of the basic methods of determining the mechanical properties of a material is the unconfined compressive strength (UCS) test, from which the material elasticity can be determined.

Compacted Anthropogenic Materials as Backfill for Buried Pipes.

Buried pipe design requires knowledge about the fill to design the backfill structure. The interaction between the backfill envelope and the pipe impacts the structural performance of the buried pipe. The backfill material and compaction level respond to the backfill's overall strength and, therefore, for pipe-soil interaction.

Warsaw Glacial Quartz Sand with Different Grain-Size Characteristics and Its Shear Wave Velocity from Various Interpretation Methods of BET.

After obtaining the value of shear wave velocity () from the bender elements test (BET), the shear modulus of soils at small strains () can be estimated. Shear wave velocity is an important parameter in the design of geo-structures subjected to static and dynamic loading. While bender elements are increasingly used in both academic and commercial laboratory test systems, there remains a lack of agreement when interpreting the shear wave travel time from these tests.

Long-Term Cyclic Loading Impact on the Creep Deformation Mechanism in Cohesive Materials.

Long-term cyclic loading is observed in a wide range of human activities, as well as in nature, such as in the case of ocean waves. Cyclic loading can lead to ratcheting which is defined as progressive accumulation of plastic deformation in a material. Long-term cyclic loading causes a time effect (creep), which is a secondary compression effect.

Magnetic, Structural and Spectroscopic Properties of Iron(II)-Octacyanoniobate(IV) Crystalline Film Obtained by Ion-Exchange Synthesis.

Over recent years, investigations of coordination polymer thin films have been initiated due to their unique properties, which are expected to be strongly enhanced in the thin film form. In this work, a crystalline [Fe(HO)][Nb(CN)]∙4HO (1) film on a transparent Nafion membrane was obtained, for the first time, via ion-exchange synthesis. The proper film formation and its composition was confirmed with the use of energy dispersive X-ray spectroscopy and infrared spectroscopy, as well as in situ Ultraviolet-Visible (UV-Vis) spectroscopy.

Estimation of Recycled Concrete Aggregate's Water Permeability Coefficient as Earth Construction Material with the Application of an Analytical Method.

Creating models based on empirical data and their statistical measurements have been used for a long time in the economic sciences. Increasingly, these methods are used in the technical sciences, such as construction and geotechnical engineering. This allows for reducing the costs of geotechnical research at the design stage.

Dinuclear molecular magnets with unblocked magnetic connectivity: magnetocaloric effect.

A detailed study of the magnetocaloric effect in two isostructural bimetallic compounds {[M(HO)][Nb(CN)]·4HO} (M = Mn, Fe) is presented. The substances show sharp phase transitions to the long-range magnetically ordered state with ferromagnetic coupling between M and Nb sublattices in the case of the Fe-based sample (FeNb, = 43 K) and antiferromagnetic coupling for the Mn-based sample (MnNb, = 50 K). The magnetic entropy change was found to reach 5.

Deformation Behavior of Recycled Concrete Aggregate during Cyclic and Dynamic Loading Laboratory Tests.

Recycled concrete aggregate (RCA) is a relatively new construction material, whose applications can replace natural aggregates. To do so, extensive studies on its mechanical behavior and deformation characteristics are still necessary. RCA is currently used as a subbase material in the construction of roads, which are subject to high settlements due to traffic loading.

[1,4]-sigmatropic rearrangement of chiral nitrones and their utilization in the synthesis of new iminosugars.

Reflection on the epimerization of the α-stereocenter of sugar nitrones leads to the conclusion that the process may occur through [1,4]-sigmatropic rearrangement. Participation of an ionic mechanism was excluded by a deuterium labeling experiment, and DFT calculations showed a reasonable energy barrier for the proposed [1,4]-shift. Products of the intramolecular 1,3-dipolar cycloaddition of the studied nitrones were utilized in the diversity-oriented synthesis of polyhydroxy derivatives of piperidine, indolizidine and quinolizidine.

Environmental and Geotechnical Assessment of the Steel Slags as a Material for Road Structure.

Slags are the final solid wastes from the steel industry. Their production from waste and associated materials is a proper implementation of the basic objectives and principles of the waste management. This study aims to investigate the chemical and selected significant geotechnical parameters of steel slag as the alternative materials used in road construction.

Synthesis of novel aza-analogues of tiazofurin with 2-[5,5-bis(hydroxymethyl)pyrrolidin-2-yl] framework as sugar mimic.

The novel aza-analogues of tiazofurin (TZF) with 2-[5,5-bis(hydroxymethyl)pyrrolidin-2-yl] moiety, as sugar mimic, were synthesized from O,O-cyclohexylidene derivative of 4,4-bis(hydroxymethyl)-4-nitrobutanal in multi-gram scale. The synthetic route consisted of three stages: (i) the synthesis of corresponding derivative of 5,5-bis(hydroxymethyl)pyrrolidine-2-carbonitrile, (ii) the construction of ethyl thiazole-2-carboxylate part by the conversion of the pyrrolidine-2-carbonitrile into the N-trifluoroacetyl derivative followed by cyclocondensation with L-cysteine ethyl ester and then by dehydrogenation, and (iii) the final transformation of the ethyl thiazole-4-carboxylate into the aza-analogues of TZF. The TZF aza-analogues were evaluated for their antiviral activities in cell-culture-based assays.

Synthesis and antiviral properties of aza-analogues of acyclovir.

Aza-analogues of Acyclovir were obtained from N-(2-pivaloyloxyethyl)-N-(pivaloyloxymethyl)-p-toluenesulfonamide via a one-pot base silylation/nucleoside coupling procedure. The antiviral activities of all aza-nucleosides in vitro against a variety of viruses were evaluated. None of these compounds displayed any specific antiviral effects.