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BACKGROUND: Pressing massage applied to myofascial trigger points (MTrPs) has shown clear effect in relieving pain. However, further research is needed to investigate the effects of different levels of pressure applied during the massage. OBJECTIVE: To investigate the different strength of pressing on MTrPs in rats with chronic pain. METHODS: Sixty SPF-rated male Sprague-Dawley rats were randomly divided into a blank group of 10 rats not involved in MTrPs modeling and 50 rats involved in modeling. The MTrPs model was established in the left medial thigh muscle of rats by blunt strikes combined with centrifugal exercise and 40 rats that met the evaluation criteria after modeling were randomly divided into model group, light press group, medium press group and heavy press group, with 10 rats in each group. The rats in the blank group and the model group were not intervened, while the rats in the light press group, the medium press group and the heavy press group were intervened with a homemade press stimulator with light force (0.3 kg), medium force (0.5 kg) and heavy force (0.7 kg) to MTrPs. The intervention time was 7.5 minutes per session, with one session every other day, totaling seven sessions. Electromyogram, soft tissue tension and mechanical pain threshold were detected by electrophysiological instruments, soft tissue tension tester, and pressure painmeter, respectively. After the intervention, in the blank group, muscle tissue was taken from the inside of the left thigh, while in the other groups, MTrPs tissue was taken. The pathological morphology was observed by hematoxylin-eosin staining, while enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of cyclooxygenase-2, prostaglandin E2 and bradykinin. RESULTS AND CONCLUSION: Compared with the blank group, the model group had lower mechanical pain thresholds, higher soft tissue tone, higher amplitude frequency of spontaneous electrical activity, significant pathomorphological changes, and increased levels of cyclooxygenase-2, prostaglandin E2 and bradykinin (P < 0.05). Compared with the model group, the medium press group and the heavy press group showed increased mechanical pain thresholds, decreased soft tissue tension, decreased spontaneous potential frequency amplitude, and decreased levels of cyclooxygenase-2, prostaglandin E2 and bradykinin (P < 0.05), and significant recovery on pathomorphological changes. No significant changes in the above indicators were observed in the light press group (P > 0.05). Compared with the medium press group, the heavy press group showed better improvement in the above indicators (P < 0.05). To conclude, moderate to heavy pressing is often required to alleviate MTrPs pain. [ABSTRACT FROM AUTHOR]

Waste plywood containing phenol–formaldehyde (PF) resin is one of the materials that are difficult to use in the production of particleboards based on UF resin. Therefore, the aim of this research was to analyze the possibility of using this type of waste in the production of particleboards bonded with melamine-urea-phenol-formaldehyde (MUPF) resin in order to determine their suitability for particleboard production. The pressing process and density profile of three-layer particleboards were presented. The press closing time for mats containing only recovered particles in the core layer (100%), produced with a face layer ratio of 50%, a resin load for a face layer of 12%, and a core layer of 10%, at a unit pressure of 3 MPa, was 29% shorter than for the industrial particle mats. Regardless of the level of variability of independent factors, the heating time of the mats containing recovered particles was 10–20% shorter than the heating time of the mats with industrial particles. The greatest impact on the maximum density of the face layer of particleboards was observed for the content of the recovered particles and then the resin load. The maximum density area of the face layer was located closer to the surface in particleboards produced with a higher (80%, 100%) content of the recovered particles, a higher (i.e., 12% and 10%, respectively, for face and core layers) resin load, a lower (35%) face layer ratio, and a higher (3 MPa) unit pressure. [ABSTRACT FROM AUTHOR]

Previous studies have shown that various additives can greatly improve the properties of copper based electrodes. In this paper, the influence of Cr content changes and different pressing and sintering process parameters on mechanical and physical properties was investigated. The results showed that 2 vol.% Cu-Cr powder composite alloys prepared by pressing pressure 450 MPa and sintering temperature of 1100 °C had the optimal mechanical and physical properties, and its density, porosity, hardness and tensile strength were 8,35 g/cm³, 2%, 124 HB and 264 MPa, respectively. In addition, the hardness was increased by 5-7% compared with that of pure copper prepared by conventional casting method. [ABSTRACT FROM AUTHOR]

In this article, a mathematical model was developed that determines the geometric and kinematic parameters of the clay mass pressing process based on the properties of the components that make up the clay mass and their initial maximum compressibility in the pressing of cylindrical ceramic products from clay masses. This mathematical model allows carrying out analytical calculations of the current compressibility, relative porosity, and current density of the clay mass depending on the size of the chamber of matrix of the press mold, the current and final displacement values of the punch and also pre-planning the geometric parameters of the press mold based on the initial properties of the clay mass. [ABSTRACT FROM AUTHOR]

Until Recently, The citizen science approach to knowledge production had been confined to scientific research, applied to a limited range of questions on which scientists and citizens could collaborate and trust each other. More recently, this approach has gained increasing attention from various quarters outside the traditional remit of professionalized science, which include local governments, civil society organizations (CSOs), professional networks, and cooperatives. These entities recognize citizen science as a practical method that harnesses the collective resources of a community to address pressing local concerns and promote a robust participatory democracy. Emerging initiatives include citizen observatories, data cooperatives, and collaboration platforms. Despite the growing popularity, managing citizen science initiatives (involving numerous participants over an extended period of time) poses considerable challenges. Leaders of citizen science initiatives grapple with difficulties that appear formidable to overcome. At present, the democratic potential of citizen science necessitates further development and scrutiny from social and political actors. Critics frequently underscore a disparity between the democratic ideals associated with citizen science and its current practical implementation. This article outlines the primary benefits and challenges associated with the democratization of citizen science. It builds from the empirical research of the ISEED project as well as the theoretical contribution of the Right to the Smart City project and formulates 10 key recommendations to citizen science project leaders. [ABSTRACT FROM AUTHOR]

In order to achieve enhanced dimensional and geometric accuracy in castings from a broad range of alloys, special processes are typically used, whose improvement, in some cases, aims to eliminate the need for machining operations on the blanks. One such process is experimental investment casting using consumable porous patterns obtained by pressing wax-like powders of model compositions. When forming the surface of such porous patterns, the geometric parameters of the mold cavity of the press die, whose design ensures the directed transfer of load from the pressing elements to the entire volume of the compacted material, are of paramount importance. During the development of the method for obtaining experimental patterns, it was possible to eliminate defects arising due to thermophysical phenomena in materials (mainly due to their internal porosity): shrinkage of the pattern material, formation of cracks within the ceramic mold, and its failure. The observed phenomena that lead to defects occur at various stages of the technological process, including the production of investment patterns and ceramic shell molds, the melting of ceramic model materials, and the casting of the melt into the molds. In addition to the definite advantages of this approach to forming compact structures, a disadvantage should be mentioned: the variation of their geometry due to the elastic return of the compacted material resulting from overconsolidation or uneven loading of compact sections of varying thicknesses. It is possible to achieve controlled loading of a powder body by compacting it under centrifugal forces to obtain compacts of complex configurations, including bodies of revolution. This paper examines the influence of various process parameters, which accompany the action of the centrifugal field, on the characteristics of compacted powder bodies made from wax-like materials used to create pressed investment patterns with improved dimensional and geometric accuracy. The study compares the calculated rotation speed of the press dies, ensuring the compaction of the powder body to a technologically acceptable density while considering its desired geometry, with the experimental results. The paper also identifies scenarios to enhance the energy efficiency of powder body compaction from wax-like composite materials under centrifugal forces. [ABSTRACT FROM AUTHOR]

The application of artificial intelligence (AI) in healthcare has gained tremendous popularity over recent years, given its enormous potential for strengthening the quality and efficiency of healthcare services on a global scale. However, the deployment of AI in healthcare comes with both benefits and risks for patients, healthcare professionals, and the whole society. Ethical concerns, such as how to prevent AI from perpetuating preexisting health disparities while incorporating its full potential in a traditional medical setting, have been pointed out by many researchers and policymakers ,. As regulatory frameworks and guidelines concerning ethical issues have been published by many organizations, there is a pressing need to present an overview of existing documents to see what has been achieved and what has yet to be emphasized in the field of AI health-related applications. [ABSTRACT FROM AUTHOR]

The development's objective is to increase productivity and reduce energy consumption in the execution of the technological process of expanded feed preparation while ensuring the necessary quality and safety of the expandates. The rationale for the construction and technological scheme of the feed expander with an improved shaping nozzle has been provided. This nozzle differs in that it consists of a narrowed area of the cylinder, a concave cone, and a crown nut. When heated plasticized mass is moved into the narrowed area of the shaping nozzle, there is an increase in pressure, followed by a sharp decrease after it passes through. This is achieved by increasing the working volume due to the shape of the concave cone. As a result, the plasticized mass expands and exits through the crown nut, forming expandates. Through numerical modelling, the dynamics and distribution of feed mixture components in the cavity between the cylinder of the shaping nozzle and the cone have been determined based on the force of pressure and the force of contact interaction between feed components. This dependence on the radius of narrowing of the cylinder of the shaping nozzle, the radius of the concave cone, and the distance between the cone and the cylinder have been established. Regression equations for the density of the plasticized feed mixture components at the outlet of the shaping nozzle and the maximum pressure required to extrude the plasticized feed components through the shaping nozzle along their movement direction from the specified research factors have been derived. As a result of experimental studies of the compact feed expander, dependencies of the changes in expander productivity, power consumption, specific energy consumption of the expansion process, and the density of obtained expandates have been established with respect to the moisture content of the compound feed, the gap between the cone and the nut, and the screw rotation speed. [ABSTRACT FROM AUTHOR]

Investigated were the influence of drying and pressing parameters of rapeseed, sunflower, and safflower seeds on oil yield, as well as antioxidant addition on the oxidative stability of cold pressed oils. The parameters of the oilseeds and cold pressed oils quality (moisture content, iodine value, saponification value, peroxide value, free fatty acids, and insoluble impurities content) were determined using standard methods. In terms of oxidative stability, rosemary, green tea, and pomegranate extracts were used as natural antioxidants, and propyl gallate was used as synthetic antioxidant. The results showed that the moisture content of the oilseeds, as well as nozzle size and electromotor frequency of the press had an effect on the yield of cold pressed oil. By reducing the nozzle size and electromotor frequency, the volume of produced cold pressed oil increased. Rosemary extract effectively increased the oxidative stability of sunflower and safflower oils, and green tea extract increased the stability of rapeseed oil. Greater stabilisation of the tested oils was achieved with the addition of 0.4 % of natural antioxidants compared to the addition of 0.2 %. The synthetic antioxidant, propyl gallate, failed to stabilise safflower oil, and unlike the natural antioxidants, it was less protective for rapeseed and sunflower oil. [ABSTRACT FROM AUTHOR]

The mechanical properties of pressings from alloy 1960 in state T1 are determined at 20, 55, 60 and 65°C. Samples of pressings from alloy 1960 in state T1 are tested for creep resistance for up to 5000 h at 55, 60 and 65°C at a stress of 295, 390 and 440 MPa. The creep rate and the deformation of the samples are determined. It is shown that increase of the temperature to 65°C in the tensile tests lowers the strength characteristics of the pressings by 20 – 40 MPa. Increase of the temperature and of the stress in the creep tests elevates the creep rate of the pressings. [ABSTRACT FROM AUTHOR]

The work presents a theoretical analysis of the process of one-sided pressing, under conditions of constant speed on the press plunger and taking into account external friction, of powder composite polymer materials based on polytetrafluoroethylene (PTFE) with small additives (less than 5%), such as silicon dioxide SiO2, kaolinite Al4[Si4O10](OH)8, carbon nanotubes, and carbon fiber. The influence on the process of compaction of materials of the speed of the press plunger, the coefficient of external friction, and the composition of the pressed material (depending on its additives) is analyzed. Based on a system of initial equations using Lagrangian variables and averaging over the radius, numerical calculations are carried out of the time dependence of the voltage on the plunger of the press for various values of the friction coefficient, geometric dimensions of the sample, and speeds of the press plunger. New visual representations are provided of the kinetics of compaction of powder materials based on polytetrafluoroethylene under constant speed of the press plunger. [ABSTRACT FROM AUTHOR]

We studied the shear bond strength (SBS) of two PEEK composites (BioHPP, BioHPP plus) with three veneering composites: Visio.lign, SR Nexco and VITA VM LC, depending on the surface treatment: untreated, sandblasted with 110 μm Al2O3, sandblasted and cleaned ultrasonically in 80% ethanol, with or without adhesive Visio.link, with applied Visio.link and MKZ primer. For the BioHPP plus, differential scanning calorimetry (DSC) revealed a slightly lower glass transition temperature (Tg 150.4 ± 0.4 °C) and higher melting temperature (Tm 339.4 ± 0.6 °C) than those of BioHPP (Tg 151.3 ± 1.3 °C, Tm 338.7 ± 0.2 °C). The dynamical mechanical analysis (DMA) revealed a slightly higher storage modulus of BioHPP (E' 4.258 ± 0.093 GPa) than of BioHPP plus (E′ 4.193 ± 0.09 GPa). The roughness was the highest for the untreated BioHPP plus, and the lowest for the polished BioHPP. The highest hydrophobicity was achieved on the sandblasted BioHPP plus, whereas the highest hydrophilicity was found on the untreated BioHPP. The highest SBSs were determined for BioHPP and Visio.lign, adhesive Visio.link (26.31 ± 4.17 MPa) or MKZ primer (25.59 ± 3.17 MPa), with VITA VM LC, MKZ primer and Visio.link (25.51 ± 1.94 MPa), and ultrasonically cleaned, with Visio.link (26.28 ± 2.94 MPa). For BioHPP plus, the highest SBS was determined for a sandblasted surface, cleaned ultrasonically, with the SR Nexco and Visio.link (23.39 ± 2.80 MPa). [ABSTRACT FROM AUTHOR]

In this study, high-pressure laminates (HPL) impregnated with phenol-formaldehyde (PF) resins enriched with kraft lignin were developed. Pulverised kraft lignin was added to the commercial PF resin in the amounts of 1% and 5% (solid to solid). Laminates were manufactured using pressure impregnation of the resins into the papers and using hot pressing of HPL in a laboratory press. Laminates with a lignin content of 1% (L-LPF-1) showed the highest bending strength (72.42 MPa) and Brinell hardness (9.41); they also exhibited the best moisture uptake (9.61) and thickness swelling after immersion in water (3.32%). Except for impact bending, laminates with a lignin content of 5% (L-LPF-5) had worse properties. However, the differences between the variants are mostly not statistically significant and are comparable with the results of commercial PF resin. Scanning electron microscopy confirmed the homogenous structure of produced laminates and the occurrence of cohesive failures in ruptured L-LPF-1 laminates, whereas in ruptured L-LPF-5 laminates adhesive failures were also observed. Based on the conducted research it can be said that the utilisation of kraft lignin as an additive to PF resin (in the amount of 1%) has a positive effect on the produced HPL. [ABSTRACT FROM AUTHOR]

The use of glass ceramic masses based on lithium disilicate, used by pressing technology (pressed ceramics), represents a very interesting alternative, and above all extremely effective for obtaining totally physiognomic prosthetic restorations. But, for the manufacture of such pressed ceramic prosthetic restorations, it is necessary not only a very good collaboration between the dental office and the dental laboratory, but also a very good professional training of all the members who make up the dental medical team: prosthodontist, dental nurse and dental technician. [ABSTRACT FROM AUTHOR]

This study reports on the possibility of applying one-part pressed geopolymers as a support for microfiltration membranes. The mineralogical, physical, mechanical, microstructural and hydraulic properties of the investigated materials are presented. Metakaolin-based geopolymeric membrane flat supports were synthesized by uniaxial pressing a dry-mixed powder (Si/Al = 1.45, Na/Al = 0.9, Na/Si = 0.62, H 2 O = 12%), with pressure between 2 and 20 MPa and a curing temperature of 70 °C. Mixing and pressing optimization resulted in samples with a total open porosity up to 39%, a modal pore diameter up to 23.5 μm and a flexural strength up to 20.4 MPa. Permeation measurement with demineralized water and ethanol-water solutions were carried out using a dead-end geometry membrane apparatus. A hydraulic permeability up to 31.3 · 103 L h−1 m−2 bar−1 has been obtained. Furthermore, permeation tests using water-ethanol solutions have demonstrated that the material is hydrophilic. These results highlighted the potential of geopolymers as microfiltration support. • Pressed one-part geopolymers are suitable to be used as membrane supports. • Geopolymer membrane supports possess a peculiar threshold pressure. • Geopolymer supports have similar characteristics to ceramic membrane supports. [ABSTRACT FROM AUTHOR]

The article presents a study of biological processing of milk of cows, goats and the mixture of cow's and goat's milk (50:50) by applying the cultures of L. acidophilus during the production of cheeses with a low temperature of the second heating. This approach accelerates the technological process by 3-4 times and guarantees a long-term storage of products without deteriorating their quality. The reduction of the time of rennet curd formation, whey removal, kneading, hot self-pressing, salting and ripening were specific features of the production process. The study showed the dynamics of fermenting microbial flora's quantity as well as the content of benzoic and sorbic acids, which guarantee the longterm storage of cheeses. We have studied the influence of our technology on physicochemical and rheological parameters of cheeses in relation to the type of milk. [ABSTRACT FROM AUTHOR]

Composite materials have a wide range of functional properties, which is ensured by using various technological methods of obtaining both the matrix or fillers and the composition as a whole. A special place belongs to the composition formation technology, which ensures the necessary structure and properties of the composite. In this work, a computer simulation was carried out to identify the main dependencies of the behavior of composite materials in the process of the main technological operations of their production: pressing and subsequent sintering. A polymer matrix randomly reinforced with two types of fillers: spherical and short cylindrical inclusions, was used to construct the finite element models of the structure of composites. The ANSYS Workbench package was used as a calculation simulation platform. The true stress–strain curves for tension, Poisson's ratios, and ultimate stresses for composite materials were obtained using the finite element method based on the micromechanical approach at the first stage. These values were calculated based on the stretching diagrams of the matrix and fillers and the condition of the ideality of their joint operation. At the second stage, the processes of mechanical pressing of composite materials were modelled based on their elastic–plastic characteristics from the first stage. The result is an assessment of the accumulation of residual strains at the stage before sintering. The degree of increase in total strain capability of composite materials after sintering was shown. [ABSTRACT FROM AUTHOR]

The dependences of the physicomechanical, thermophysical, and dielectric properties of a ceramic composite based on magnesium oxide on the sample formation method are studied. The main reasons for the sample behavior in tests and the advantages and disadvantages of slip casting and pressing methods are discussed. The influence of the sample formation method on the distribution of the reinforcing component is studied. [ABSTRACT FROM AUTHOR]

Quantum communications is a promising technology that will play a fundamental role in the design of future networks. In fact, significant efforts are being undertaken by both the quantum physics and the classical communications communities on developing new architectures, solutions, and practical implementations of quantum communication networks (QCNs). Although these efforts led to various advances in today's technologies, there still exists a non-trivial gap between the research efforts of the two communities on designing and optimizing the performance of QCNs. For instance, most prior works by the classical communications community ignore important quantum physics-based constraints when designing QCNs. For example, many existing works on entanglement distribution do not account for the decoherence of qubits inside quantum memories and, thus, their designs become impractical since they assume an infinite lifetime of quantum states. In this article, we bring forth a novel analysis of the performance of QCNs in a physics-informed manner, by relying on the quantum physics principles that underly the different components of QCNs. The need for the physics-informed approach is then assessed and its fundamental role in designing practical QCNs is analyzed across various open research areas. Moreover, we identify novel physics-informed performance metrics and controls that enable QCNs to leverage the state-of-theart advancements in quantum technologies to enhance their performance. Finally, we analyze multiple pressing challenges and open research directions in QCNs that must be treated using a physics-informed approach to lead practically viable results. Ultimately, this work attempts to bridge the gap between the classical communications and the quantum physics communities in the area of QCNs to foster the development of the future communication networks toward the quantum Internet. [ABSTRACT FROM AUTHOR]

This study aims to develop a pressed concrete roofing tile from powder technology containing basalt powder in substitution of fine sand (aggregate) for application in building covers. Specimens were submitted to technological and toxicological characterization. Hence, pressed specimens based on cement and basalt powder were analyzed. In the bending strength test, the pressed samples containing a cement:basalt mass ratio of 1:6, water content of 5% and specific pressure of 25 MPa revealed a value of 3.82 ±0.46 MPa at 28 days of curing, while the molded samples (reference) with cement:sand mass ratio of 1:5 and 15% water content revealed 1.72 ±0.86 MPa. This composition, containing cement and basalt powder, is not toxic, confirming the possibility for total replacement of sand by basalt powder. Thus, it was demonstrated that the technical viability for the proposed process and the use of basalt powder to obtain pressed flat concrete roof tile meets technical requirements and standards, compared to conventional concrete roofing tiles. [ABSTRACT FROM AUTHOR]

Studies have been carried out to develop the sintering mode and analyze the properties of tablets obtained by fabricating carbon black powders with the addition of nickel stearate at various pressing pressures. Based on the thermal analysis of samples of nickel stearate used in the experiments, the sintering mode of the carbon tablets under study was worked out. With the help of X-ray fluorescence analysis data, the presence of nickel in the obtained tablets was confirmed. As a result of tests of tablets for mechanical strength, the possibility of carrying out the process of saturation of carbon tablets with hydrogen at pressures significantly exceeding atmospheric pressure was proved. [ABSTRACT FROM AUTHOR]

The composition and morphology of a ceramic material based on magnesium oxide and their influence on its thermophysical and physicomechanical properties are studied. It is established that the matrix component has the same morphological features and is cubic magnesium oxide when different initial precursors are used. The dependences of the physical and mechanical properties on the type of precursor and method of molding were studied on experimental samples. [ABSTRACT FROM AUTHOR]

Both the mass and centrifugal force can be reduced by the hollow structure in blade. Also, the working efficiency of the engine can be improved by this hollow structure, but this structure is complicated and difficult to be formed. A pressing process of hollow blade with low melting point alloy as mandrel is proposed. The results show that the shape of the hollow blade can be controlled better by filling the low melting point alloy. The supporting structure has a great influence on the forming effect of unfilled low melting point alloy blade. The more supporting structures, the better the forming effect. The interface between the blade and the low melting point alloy cannot be bonded, so this processing method can be applied to practical production. [ABSTRACT FROM AUTHOR]

Pulsed electric fields (PEFs) are becoming more and more popular in different applications in processing agricultural products. The PEF technology is based on the application of high voltage short pulses that allow electroporation in the cell membranes. This review outlines the PEF applications used in processing sugar beets. New perspective technologies of the cold or warm aqueous extraction of sugar, cold pressing of sugar beet cossettes, and combined pressing-diffusion process are discussed. Electroporation devices for pilot and industrial applications in the sugar beet industry are also presented. [ABSTRACT FROM AUTHOR]

Background. A number of studies is being carried out aimed at accelerating the firing process of ceramic masses due to mechanical activation, which saves energy and improves the quality of the product. We note the low level of scientific research in this area in our country. Purpose. The purpose of the study: to analyze the possibility of using the mechanical activation method to improve the quality and reduce the cost of ceramic products based on loess-like rock. Methodology: Modern methods of physical-chemical and physical-mechanical studies were used, including laser diffraction (diffraction analyzer ANALYSETTE 22 Nano Tec plus.), X-ray and electron microscopy methods. Originally. It is shown that the mechanical activation of loess-like rocks leads to an increase in the number of clay particles by 63.7%, dust particles by 28.25%, and a decrease in the number of sand grains by 58.7%. It is noted that the technological properties of this mass have changed, including plasticity - from 5.0 to 10.4; semi-finished product compressive strength - from 1.09 to 1.24 MPa. Findings. It is shown that the optimal grinding time is 120 min. The plasticity of the formed mass is increased by (94.6%). The grinding of loess-like rock and glass flour leads to an increase in the amount of clay particles by 63.7%, dust particles by 28.25%, and sandy particles by 58.7%. The compressive strength can be increased (86.5%) and the cooking temperature is reduced by 50°C. [ABSTRACT FROM AUTHOR]

A porous, catalytically active converter was synthesized based on coarse SiC. For the synthesis of the converter, ultrafine additives of the eutectic composition MgO and SiC were introduced into the original SiC powder. The resulting mixture was pressed at the maximum pressure from 75 to 125 MPa, followed by sintering in the range from 1200 to 1450°C. The open porosity of the converters was ~40%, the size of the pores ranged from 4 to 6 μm. At 600°C, ethylbenzene conversion was ~73%, styrene yield ~9%, selectivity of styrene ~12.3%. The degree of carbonization of the catalyst after 2.5 h did not exceed ~0.003 wt.%, which is an ultra-low indicator that radically increases the life of a catalytic converter without the need for regeneration or replacement. [ABSTRACT FROM AUTHOR]

While cast geopolymers are deeply investigated, geopolymers shaped by pressing are still rather unexplored. This work aims at developing one-part pressed geopolymers investigating the influence of parameters such as Na/Al molar ratio, water content and pressure load on the physical, microstructural and durability properties of the hardened geopolymers. Geopolymers were prepared by dry mixing and cured at 70 °C for 24 h and at room temperature for further 6 days. Density, water absorption, porosity features, microstructure and durability have been determined for all the samples. The results show that Na/Al molar ratio, water content and pressure load are key parameters to control the properties of one-part geopolymers. Their optimization can allow to obtain geopolymers suitable for microfiltration flat membrane support. Finally, the best performances in terms of durability are obtained when using the highest pressure load (20 MPa) and water content (15%). [ABSTRACT FROM AUTHOR]

In this article, we report a method for preparing high quality FeSe $_{1-x}$ Te $_x$ targets with tunable density using a high-pressure sintering process. The phase formation of the target is checked by X-ray diffraction. The targets show a single phase and can be indexed to a tetragonal structure with the space group of P4/nmm. Compared with the target prepared by the normally used solid-state reaction method, the density has been dramatically increased to 92.10% of the theoretical density. We also developed a more effective method of adjusting the density of the FeSe $_{1-x}$ Te $_x$ targets by changing the sintering temperature at a constant pressure. The preparation method of our FeSe $_{1-x}$ Te $_x$ target promises to provide an opportunity for the preparation of long coated conductors. [ABSTRACT FROM AUTHOR]

Nanocomposites of chitosan and cerium oxide‑cadmium oxide (CeO 2 -CdO) nanopowder were developed to fabricate impedimetric humidity sensors. The low temperature-stirring was used to synthesize CeO 2 -CdO nanopowder. Average particle size of synthesized nanopowder was 100 ± 20 nm. Various composition of chitosan-CeO 2 -CdO nanocomposites were developed using echo-friendly (mechanical mixing) technique. Pellets of 13.0 mm diameter and 1.0 ± 0.1 mm thickness were prepared using hydraulic press under the pressure of 375 MPa. Silver paste was used to deposit the electrodes; the length of each electrode was 12.0 mm and the gap between two electrodes was 2.0 ± 0.5 mm. The mechanism of sensing is based on impedimetric change in response to humidity variation. Fabricated sensors showed high sensitivities ranging from −930.0 kΩ/%RH to −2091.1 kΩ/%RH. Response and recovery times are up to 1 s, while the humidity sensing range is 5 to 95%RH. The fabricated sensors are very attractive to use in several devices for environmental monitoring and biomedical applications. [ABSTRACT FROM AUTHOR]

Contraction of solid elements and compounds by cooling from room temperature to 0 K or by mechanical pressing to the same volume at 298 K is experimentally determined. We found that the energy cost of cold compression exceeds the energy of mechanical compression on average by two orders of magnitude. This fact is caused by the different mechanisms of contraction: pressing directly reduces interatomic distances, cooling mainly reduces the amplitudes of harmonic vibrations of atoms, whereas the anharmonic part of the vibration energy, responsible for the thermal contraction, is very small, ca. 1%. [ABSTRACT FROM AUTHOR]

This study aims to simplify the driving system of pneumatic soft robots by developing a lightweight and small-sized multimode flow control valve (MMFCV). It can be embedded in robots as the components, and thus it requires no conventional valves with large size and heavy mass, which significantly reduced the volume and mass of the driving system. The valve is comprised of an input port, an output port, a positive port, and a negative port. By designing the connection of these ports to the actuators, the MMFCV can work in three different modes: one-direction delay mode, delay deflating mode, and double-port control mode. The pressure output characteristics of the MMFCV are modeled, and the validity is verified through experiments. In addition, a robot that comprised of two radial expansion modules, one axial expansion module, and four MMFCVs are fabricated, and the body is driven by the air pressure from the air supply through only one tube. The results of the pipe crawling experiments demonstrate that the MMFCV with multimode increased the flexibility of circuit and time sequence of the air flow, which can reduce the number of the tubes from the air supply to the robot. As a result, it reduced the load pulled by the tubes, and prevented the mission failure from the risk of entanglement of the tubes. [ABSTRACT FROM AUTHOR]

We study the microstructure, phase composition, strength and plasticity characteristics, and crack-growth resistance under cyclic loading of thermally deformed (by extrusion, pressing, and rolling) castings of Al-Mg-Sc alloys (of the 1570 and 1545 types) with different magnesium contents obtained as a result of magnetohydrodynamic stirring of melt. It is shown that the grain size of the alloy after rolling and the amount of grain-boundary precipitates of intermetallic compounds decrease as the magnesium content of the alloy becomes lower. The mechanical characteristics of both alloys ambiguously depend on the procedure and temperature of thermomechanical treatment. It is shown that the parameter of structural strength of the investigated alloys (complexly determined by the characteristics of strength and fatigue crack-growth resistance) is higher than for the available Al-Mg-Sc, Al-Mg, and Al-Cu-Mg alloys. At the same time, its lowest value was recorded for the alloy with fine grains. [ABSTRACT FROM AUTHOR]

The performance of a fuel cell depends on multiple factors, one of the most important being the preparation of the membrane electrode assembly (MEA). In the present work, MEAs constituted by gas diffuser electrodes (GDE) were pressed with carbon supported platinum catalysts. As solid electrolyte, a commercial polymeric membrane from Nafion was used, which was pressed at two GDE with loads of 5 and 1.5 mg/cm2 of catalyst at different temperatures and pressures for a fixed period of time. The assembly was characterized electrochemically using linear sweep voltammetry and electrochemical impedance spectroscopy at three different potentials. Also, the behavior when reversing the supply of hydrogen and oxygen to the GDE was studied. The results of the study showed a great dependence of the charge transfer resistance with the temperature, being secondary the dependence with the pressure in the range of temperature and pressure analyzed. Likewise, changes were observed in the open circuit potential after varying the temperature, pressure and catalyst load, hence affecting its maximum power and efficiency at that point. [ABSTRACT FROM AUTHOR]

The present investigation compares for the first time the effect of the addition of TiO 2 on Al 2 O 3 ceramic materials prepared by uniaxial pressing and extrusion technique. The properties of the disc- and tubular-shaped materials were investigated using different experimental tests, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Archimedes porosity, linear shrinkage, mechanical performance and scanning electron microscopy (SEM). The XRD analysis revealed the formation of Al 2 TiO 5 phase at 1400 °C for discs and tubes, and became more evident when the sintering was performed at 1500 °C. The increase of TiO 2 loading did not affect the open porosity at a given temperature for the tubular- and disc-shaped samples. The addition of 1 wt% TiO 2 led to a remarkable increase of tensile strength for the disc-shaped materials heat treated at all temperatures due to the formation of aluminum titanate. However, a further addition on the TiO 2 loading appears to decrease the tensile strength of the disc-shaped samples heat treated at 1400 °C and 1500 °C. For instance, the flexural strength of the tubes improved with increasing TiO 2 loading and sintering temperature from 1300 °C to 1500 °C. This effect was attributed to the occurrence of a more effective formation of Al 2 TiO 5 on the ceramic tubes. Furthermore, the addition of TiO 2 played a key role in controlling the open porosity and the microstructure as confirmed by the SEM images in ceramics obtained by uniaxial pressing and extrusion processing. [ABSTRACT FROM AUTHOR]

The photoelectret property of a high-density polyethylene (HDPE)-semiconductor (n-InSe) composite is investigated. It was found that the magnitude of the photoelectret potential non-monotonically depends on the n-InSe content. Treatment under the action of an electric discharge plasma in an electronegative gas significantly affects the magnitude of the photoelectret potential and its dependence on the content of the semiconductor filler in the composite. It is shown that in the considered case the main source of electric charge generation is the filler, and in the process of polarization the determining one is the electric field at the polymer-semiconductor interface. This composite is promising for optoelectronics. [ABSTRACT FROM AUTHOR]

The integrated starter generator used in micro hybrid electric vehicle is usually claw pole motor. The claw pole core in the motor is forged by low carbon steel, which is of complex technology and the eddy current loss of the whole conductor in the magnetic field is large. To solve these problems, a novel claw pole motor is proposed in this article, which uses iron-based soft magnetic composites to prepare claw pole core and to insert permanent magnet between claw poles. By studying the preparation process parameters of iron-based soft magnetic composites, it is found that the mechanical properties and magnetic properties of the soft magnetic composites are the best under 700 MPa pressing pressure and 500 °C annealing temperature. A prototype is designed and manufactured, and its power generation and starting performance are tested, which can meet the performance requirements of 48 V micro hybrid system. [ABSTRACT FROM AUTHOR]

The copulation of insects takes place in antipodal, inverse antipodal, sympodal, inverse sympodal, reverse sympodal, pseudosympodal, epipodal, reverse epipodal, crucipodal, semiepipodal, reverse semiepipodal, clinopodal, schizopodal, reverse schizopodal, inverse schizopodal, semischizopodal, reverse semischizopodal, orthopodal, reverse orthopodal, lateralopodal, parallelopodal, indirect parallelopodal, indirect frontalopodal, pseudoepipodal, inverse pseudoepipodal, cyclopodal, pseudocyclopodal and sinusoidal position of male and female. The copulation of stick insects or walking sticks (Phasmatodea) takes mainly place in epipodal and semiepipodal position of male and female as well as subordinately to accessorily also in crucipodal, schizopodal, parallelopodal, inverse antipodal, orthopodal and antipodal position of both partners, whereas other positions of male and female do not occur in the pairing of stick insects or walking sticks. The copulation of heelwalkers or gladiators (Mantophasmatodea) takes exclusively place in epipodal and partially established crucipodal position of male and female, whereas other positions of both partners do not occur in the pairing of heelwalkers or gladiators. The copulation of ice crawlers and rock crawlers (Grylloblattodea) takes mainly place in epipodal and partially established crucipodal position of male and female as well as subordinately also in antipodal position of both partners, whereas other positions of male and female do not occur in the pairing of ice crawlers and rock crawlers. The copulation of cockroaches (Blattodea) takes almost exclusively place in antipodal position of male and female and only occasionally probably also in epipodal position of both partners, whereas other positions of male and female do not occur in the pairing of cockroaches. The copulation of twisted wings (Strepsiptera) takes exclusively place in inverse pseudoepipodal position of male and female, whereas other positions of both partners do not occur in the pairing of twisted wings. The copulation of fringed wings or thripses (Thysanoptera) takes place in reverse epipodal, reverse semiepipodal, crucipodal, reverse schizopodal and antipodal position of male and female, whereas other positions of both partners do not occur in the pairing of fringed wings or thripses. The copulation of earwigs (Dermaptera) takes mainly place in antipodal position of male and female as well as subordinately to accessorily also in schizopodal and parallelopodal position of both partners, whereas other positions of male and female do not occur in the pairing of earwigs. The copulation of moss bugs or beetle bugs (Hemiptera: Coleorrhyncha) takes probably place in epipodal position of male and female. The copulation of fleas (Siphonoptera) takes exclusively place in reverse epipodal position of male and female, whereas other positions of both partners do not occur in the pairing of fleas. The copulation of barklice and booklice (Psocoptera) takes mainly place in reverse epipodal position of male and female as well as subordinately also in antipodal and reverse orthopodal position of both partners and possibly sometimes even in epipodal position of male and female, whereas other positions of both partners do not occur in the pairing of barklice and booklice. The copulation von plant lice (Hemiptera: Sternorrhyncha) takes mainly place in epipodal and orthopodal position of male and female and occasionally also in schizopodal and parallelopodal position of both partners, whereas other positions of male and female do not occur in the pairing of plant lice. The copulation of lice (Phthiraptera) takes mainly place in reverse epipodal and inverse antipodal position of male and female as well as possibly occasionally also in epipodal and schizopodal position of both partners, whereas other positions of male and female do not occur in the pairing of lice. The copulation of ground lice or angel insects (Zoraptera) takes mainly place in inverse antipodal position of male and female as well as subordinately also in reverse epipodal and parallelopodal position of both partners, whereas other positions of male and female do not occur in the pairing of ground lice or angel insects. The copulation of jumping bristletails (Archaeognatha), silverfish or fishmoths (Zygentoma) and two-pronged bristletails (Diplura) takes exclusively place in indirect parallelopodal position of male and female, whereas other positions of both partners do not occur in the pairing of jumping bristletails, silverfish or fishmoths and two-pronged bristletails. The copulation of springtails (Collembola) takes mainly place in indirect parallelopodal position of male and female and subordinately also in indirect frontalopodal position of both partners, whereas other positions of male and female do not occur in the pairing of springtails. The different positions during the copulation of stick insects or walking sticks (Phasmatodea), heelwalkers or gladiators (Mantophasmatodea), ice crawlers and rock crawlers (Grylloblattodea), cockroaches (Blattodea), twisted wings (Strepsiptera), fringed wings or thripses (Thysanoptera), earwigs (Dermatoptera), moss bugs or beetle bugs (Hemiptera: Coleorrhyncha), fleas (Siphonaptera), barklice and booklice (Psocoptera), plant lice (Hemiptera: Sternorrhyncha), lice (Phthiraptera), ground lice or angel insects (Zoraptera), jumping bristletails (Archaeognatha), silverfish or fishmoths (Zygentoma), springtails (Collembola) and two-pronged bristletails (Diplura) are described, and the systematical distribution of the different positions during the pairing is explained and illustrated with examples from the individual orders, families and genera of stick insects or walking sticks (Phasmatodea), heelwalkers or gladiators (Mantophasmatodea), ice crawlers and rock crawlers (Grylloblattodea), cockroaches (Blattodea), twisted wings (Strepsiptera), fringed wings or thripses (Thysanoptera), earwigs (Dermatoptera), moss bugs or beetle bugs (Hemiptera: Coleorrhyncha), fleas (Siphonaptera), barklice and booklice (Psocoptera), plant lice (Hemiptera: Sternorrhyncha), lice (Phthiraptera), ground lice or angel insects (Zoraptera), jumping bristletails (Archaeognatha), silverfish or fishmoths (Zygentoma), springtails (Collembola) and two-pronged bristletails (Diplura). Distribution and abundance of the different positions in the copulation of male and female in the different orders of insects are summarized in the tables 1 - 6 in the attachment. [ABSTRACT FROM AUTHOR]

The present paper is intended to be a brief presentation of the current state of rolling of metal slats profiles. The author presents some theoretical considerations regarding the rolling process in the case of metal slat profiles. The first part of the paper presents the rolling process which is the most common process of plastic deformation of cold metal materials with the help of special equipment called rolling mills. The process having the advantage of an efficient processing of the metallic material, in the conditions of ensuring a good dimensional precision and a qualitative surface. Lamination processing consists in pressing the semi-finished product when passing between two cylinders that rotate in the opposite direction and are characterized by the degree of deformation of the material. When the sheet is bent, the surface inside the bend is compressed and the outside surface is stretched. Somewhere inside the thickness of the sheet is the neutral axis, the axis that does not compress or stretch, remaining the same length throughout the bend. Laminating is suitable for obtaining long pieces with a constant section, which cannot be obtained by other processes, but also for obtaining complicated finished products such as geometric shape. For the calculation of structures made of cold-formed steel profiles, specific calculation rules have been developed. Currently, the latest version is in the form of SR-EN 1993-1-3 from 2007. Also, in the second part of the work is presented the way of protection against corrosion of metal slat profiles and advantages of using cold formed steel profiles. The metal slat is made of galvanized steel and pre-painted in electrostatic field, which gives a high resistance to environmental factors, as well as an increased mechanical resistance. Galvanizing and painting the profiles brings an increased degree of corrosion protection of the element in the environment. An application of a 0.04 [mm] thick layer provides the standard protection required by regulations, ensuring a safe life of the structure of approximately 60 years. The third part of the paper highlighted the advantages of metal slats and the field of use of metal slat profiles, namely the use for fence panels that surround buildings, producing in various assortments of colors and sizes. [ABSTRACT FROM AUTHOR]

The radial- shift mill (RSM) of a new design, which makes it possible to obtain high quality rods by the combined rolling-pressing process is proposed in this article. By using the MSC.SuperForge program the quantitative data has been obtained and main regularities of the stress-strain state distribution during rolling in smooth, helical rolls and rolling-pressing of billets on a RSM of a new design were established. Special attention is paid to the influence analysis of rolling in smooth and helical rolls and to the rolling-pressing on the formation of structures in rods from M1copper alloy. It has been established that processing by the combined process makes it possible to form a finegrained structure along the cross-section of the bars without disrupting the continuity of the billet material. By using physical modeling the effect of temperature-deformation processing modes on the kinetics of dynamic recrystallization of copper alloy M1has been studied. The dependence of the size of the recrystallized grain from temperature and degree of deformation has been established. [ABSTRACT FROM AUTHOR]

The Republic of Uzbekistan is a major producer of agricultural products. The production of vegetables, grapes, fruit and berries, melons and gourds is increasing from year to year. The total volume of their production approximates 16,200 thousand tonnes a year. The seeds of these crops make up 2 to 10% of the mass of processed raw materials and are sources of valuable bioactive substances. The main method of obtaining oil (from apricot kernels, grape and melon seeds) is cold pressing, i.e. pressing carried out at a temperature below 60°C. Such oil immediately passes from the category of ordinary table oils to the category of medicinal products. At present, in Uzbekistan, to obtain high-quality vegetable oil, apricot kernels, grape and cucurbit seeds are processed on low-tonnage production lines by cold pressing. However, this method of processing raw materials does not provide the maximum yield of valuable vegetable oil and its nutrients. Oil cakes are not processed to obtain bioactive substances, nor is extraction practised as a method of obtaining them. Unlike other solvents such as butane or hexane, ethanol, when used for extraction, has the advantage of being virtually harmless to the user. Unlike so-called CO2 extraction, that with ethanol requires no expensive equipment, and if the technology is observed, the extract obtained can have spectra of a very high quality. There is no scientifically substantiated methodology of engineering calculation of a low capacity plant using an ethanol solvent to extract ingredients from vegetable materials. This shows how important it is to develop such equipment and introduce it in production. [ABSTRACT FROM AUTHOR]

An alternative method for determining the empirical coefficients of the Kunin-Yurchenko equation of pressing is proposed. This method consists in constructing a polynomial regression tertiary model of the dependence of the density on the pressing pressure with subsequent approximate calculation of the empirical coefficients. The application of the proposed method showed good agreement with the experimental results (correlation ratio is not less than 0.97). Comparing the data obtained by the proposed method and the data obtained by the well-known method of "three pressings", the same accuracy was found for both metallic and non-metallic powder materials. When processing large data arrays, for example, in adaptive algorithms for controlling the pressing process, it is preferable to use the proposed method, since it takes into account the influence of all experimental data on the compacting process of powder materials in the operating pressure range. [ABSTRACT FROM AUTHOR]

The efficiency of insignificant additions of clay and kaolin in relation to the production of molded and unmolded ceramic concretes, based on the use of HCBS of silica, aluminosilicate, high-alumina and corundum compositions, is shown. These additions can be made both as part of HCBS and in molding systems in the manufacture of ceramic concrete. Clay additives are especially effective in the manufacture of monolithic linings based on the Al2O3–SiO2–SiC–C system by vibro-pneumatic ramming. By introducing additives, it is possible to improve the rheotechnological properties of both initial HCBS of various compositions and matrix systems of ceramic concretes formed by various methods. [ABSTRACT FROM AUTHOR]

Transverse compression of bamboo occurs during manufacturing of engineered bamboo products and densified bamboo, as well as in service under compressive-loading in structures. This study investigates the transverse compression behavior of Moso bamboo and the relationship of its compression modulus with density, and provides microscopic observations of the changing cellular structure during transverse loading. When compared to softwood of same density, bamboo shows higher compression modulus and yield strength. Bamboo's matrix (parenchyma cells, vessels and sieve tubes) resembles a closed cell foam in transverse compression, presenting high density variation among specimens and plays an important role in its overall density, behavior and compression modulus. Bamboo's behavior and compression moduli are also influenced by tissue density and its natural fiber reinforced composite structure. A refined model is required and presented which captures the non-linear stress-strain behavior of bamboo considering these characteristics. The model works in a range of densities in Moso bamboo and provides accurate prediction of its transverse compression behavior and magnitude. [Display omitted] • Non-linear stress-strain relationship is response of bamboo's cellular structure. • Gradual collapse of parenchyma cells starts in low-density regions. • Parenchyma density and compression moduli are correlated to culm density. • A new model is developed for predicting stress-strain relationship. [ABSTRACT FROM AUTHOR]

This work explores the impact of pulsed electrical fields (PEF) on false mortality or latent vitality of yellow mealworms (Tenebrio molitor larvae) and following processes of hydraulic pressing (at pressure P = 6 MPa and temperature T p = 60 °C) and air drying in a ventilated oven (T d = 50–70 °C). The observed PEF effects were compared with data for blanched and frozen-thawed samples. Rinsing the larvae before the treatment significantly increased larval mortality. Analysis of SEM images revealed the presence of large-scale damages such as necrotic spots, after applying severe PEF treatment conditions to achieve complete mortality. In the pressing experiments, remarkable improvements were observed, with pressing yield increasing from 65% in untreated larvae up to 80% in PEF-treated larvae. Simultaneously, the water content of the resulting press cake decreased from 58% to 46%, with all studied samples displaying an inverse linear correlation between the press cake's water content and the pressing yield. Regarding the drying process, it was observed that blanched samples exhibited the slowest drying rate, whereas PEF-treated samples displayed a first-order kinetic process with a noteworthy acceleration in drying. These findings indicate that PEF treatment improves and boosts the overall drying process. Furthermore, PEF treatment resulted in a notable decrease in the activation energy of larvae, dropping from 80 kJ/mol for blanched and frozen-thawed samples to a range of 40–50 kJ/mol for PEF-treated larvae. This reduction in activation energy highlights the potential of PEF treatment in optimizing the overall efficiency of larval drying. T. molitor larvae were approved by the European Food Safety Authority as a novel food. It is also a promising candidate for industrial-scale production, with relatively low contamination levels and high nutrient values as food sources for humans and domestic animals (such as birds, fish, and pets). It was demonstrated that PEF treatments significantly affect larval viability and can significantly improve the pressing and drying processes of T. molitor insect biomass. Obtained data may be useful for the industrial optimization of these processes. • After PEF treatment larvae were under shock and true mortality was assessed at 24 h. • Rinsing larvae before PEF treatment enhanced mortality and treatment efficacy. • PEF treatment increased pressing yield and reduced press cake's water content. • Drying kinetics were significantly enhanced with PEF treatment. • Page model revealed the presence of a strong isolation of water in untreated larvae. [ABSTRACT FROM AUTHOR]

In this study, the possibility of using of the following technogenic raw materials to obtain a composite material was considered: titanium-containing slag, with the addition of aluminum bronze grade PG-19M-01 (TU 48-4206-156-82) and aluminum powder grade PA-4 (GOST 6058-73). The percentage of components in the mixture were as follows (wt. %): slag - 40, PG-19M-01 - 30, PA-4 - 30. A thermodynamic simulation of the selected system was preliminarily carried out using TERRA program in the temperature range 273 - 4273 K. The chemical and granulometric composition of the initial powders was investigated. From the powder mixture there were compressed the tablets and then they were sintered in an inert atmosphere. Micro-X-ray analysis of sintered samples showed that they consist of large particles of various shapes, most likely containing titanium and iron aluminides, their compounds between themselves and with copper. [ABSTRACT FROM AUTHOR]

Ring-shaped polymer-bonded magnets (RSMs) were produced from a mixture of an isotropic NdFeB powder, steel use stainless (SUS) powder, and epoxy resins as binders, using a comprehension-molding technique. Morphology of RSM determined by an SEM indicated that inappropriate molding pressure leads surface defect and brings adverse impact on properties of magnets. The research on mechanical properties shows that the maximum tensile strength of 11.4 N was achieved at optimal pressing pressure of 85 kN. Meanwhile, RSM has excellent stability as the critical component of motor and its amount of unbalance is as low as 0.754 mg. Magnetic property in optimal mechanical conditions was also found to be optimum at $H_{\mathrm {cj}} =8.42$ kA/m and (BH)max = 31.17 kJ/ $\text{m}^{3}$. [ABSTRACT FROM AUTHOR]

The article describes a method and associated equipment for determining the coefficient of lateral pressure when pressing and ejecting pyrotechnic elements depending on the compaction pressure. The dependence between the force parameters of loading, the coefficient of lateral pressure and the density of powder materials during pressing is experimentally confirmed. The results can be used to determine the parameters that comprise the passport characteristics of products made of pressed powders. [ABSTRACT FROM AUTHOR]