Low-temperature Technology Research Articles

Fabrication of silicon PIN diode with SiGe junction for soft x-ray detector using low-temperature technology

In this paper, a low-temperature technology was introduced for the fabrication of PIN photodiode. A double dielectric oxide layers were prepared by nitric acid oxidation and PECVD, respectively. The selective epitaxial growth of SiGe thin layers, which were in-situ doped in a reactive thermal chemical vapor deposition system, were applied for the preparation of PN junction and high-low junction. A SiNx passivation layer combined with a post-annealing was adopted to lower the reverse current. The temperature was controlled below 450 °C for the whole fabrication process. Finally, the reverse current of 0.7 nA was achieved at room temperature for our 5 mm-diameter PIN detector and the energy resolution of 240 eV was obtained at 5.9 keV, −60 °C. The results indicated that the low-temperature technology is suitable for the fabrication of high quality PIN detector, and the cost can be reduced effectively.

Water Electrolysis for the Production of Hydrogen to Be Employed in the Ironmaking and Steelmaking Industry

The way to decarbonization will be characterized by the huge production of hydrogen through sustainable routes. Thus, the basic production way is water electrolysis sustained by renewable energy sources allowing for obtaining “green hydrogen”. The present paper reviews the main available technologies for the water electrolysis finalized to the hydrogen production. We describe the fundamental of water electrolysis and the problems related to purification and/or desalinization of water before electrolysis. As a matter of fact, we describe the energy efficiency issues with particular attention to the potential application in the steel industry. The fundamental aspects related to the choice of high-temperature or low-temperature technologies are analyzed.

Mechanisms of low-temperature rehabilitation technologies. Extreme aerocriotherapy

The mechanisms of increasing the resistance of cells to significant temperature and damaging effects are typical, and cellular tolerance, ensuring the effectiveness of systemic regulation, is an important part of increasing the adaptive and rehabilitative potential of the entire organism. The expression of early genes encoding a wide range of stress-protective proteins increases the resistance of cells not only to significant temperature stimuli, but also to ischemia, hypoxia, and other damaging factors, forming the effects of cross-adaptation. Even a small change in temperature is significant enough to trigger the processes of genomic reprogramming. It seems to us important to consider the mechanisms of low-temperature therapeutic and rehabilitation technologies from the standpoint of cellular response to temperature stimuli. Currently, a large number of low temperature technologies (HT) are used in medical rehabilitation, which can be divided into two groups: moderately low temperature effects (from 30C to +20C) and extremely low temperature effects (from 30C to 180C), which includes the technology of extreme aerocriotherapy (EACT). The purpose of the review is to analyze the systemic and local mechanisms of EACT implemented with the participation of the main known stress-protective proteins.

Electrostatic and electrochemical charging mechanisms for electric-double-layer gating media based on a crystalline LaF3 solid electrolyte

The electric-double-layer, constituted on the interface between an electronic conductor and an ionic conductor, enables practical applications of electronic devices and electrochemistry. Specifically, the electric-double-layer interfaces have been widely reported to achieve the insulator–metal transition and interfacial superconductivity in field-effect transistors because of the large electric-double-layer capacitance and high carrier density accumulation. Recently, a crystalline LaF3 solid electrolyte has been shown to be an ideal gate medium candidate for realizing stable electric-double-layer transistors. However, the intrinsic electrostatic and electrochemical mechanisms about LaF3 electric-double-layer interfaces remain elusive. Here, by combining electrochemical-impedance-spectroscopy with low-temperature technology, we demonstrate the temperature–frequency mapping “phase diagram” for the capacitance and dielectric loss at the LaF3/metal interfaces. Two well-distinguished regions correspond to the electrostatic and electrochemical nature, providing a promising guideline for practical device applications based on the crystalline LaF3 solid electrolyte.

Development of the design and determination of the mode characteristics of the demineralizer for sea water

The object of research is block low-temperature installations for obtaining fresh water.
 Investigated problem: obtaining fresh water from sea using low-temperature technologies.
 Main scientific results: the design is developed and the operating characteristics of the demineralizer for sea water are determined.
 The influence of the initial salt content of sea water on the ice formation rate is determined. With an increase in the salinity of 3.5 times, productivity on ice decreases 2.3 times.
 The kinetics of the salt content in the freezing solution depends on the initial concentration. With an initial salt content of 6.74 g/l, the process rate is 0.4 g/h, with a salt content of 1 g/l – 0.14 g/h
 With an initial salt content of 6.74 g/l, the process of separating wastewater from the ice block is more intensive. The salt content of the first portion of the effluent is 3.2 times higher than the initial concentration of the solution.
 A cryoscopic curve was obtained for seawater in the concentration range from 0 to 6.74 g/l.
 The area of practical use of the research results: studies of the quality of the obtained water showed that the content of nitrates decreases 5 times, the hardness decreases by 2 mg/dm³. The salt content is reduced from 858 mg/dm³ to 560 mg/dm³.
 Plants for the concentration of food liquids by the block freezing method are designed to produce environmentally friendly products that preserve the bioactive complex of raw materials as much as possible with minimal energy consumption.
 An innovative technological product: design and operating modes of a block freezing plant for seawater desalination.
 Scope of application of the innovative technological product: industrial enterprises, the technological process of which requires small volumes of fresh water; to obtain fresh water on oil platforms in the oceans; small hotels, boarding houses on the seaside.

Cooling of electronic components on the LTCC module with an embedded flat heat pipe

The results of the experimental investigations of a ceramic circuit board sample with an embedded flat heat pipe are presented. The sample was made based on the technology of low temperature co-fired ceramic (LTCC). The flat heat pipe is formed at the bottom side of a ceramic substrate using a capillary structure made of sintered copper powder. The developed prototype of the LTCC module was used for the investigation of removing and spreading of high heat fluxes from high power electronic components mounted on the module. The embedded flat heat pipe filled with acetone provides 40 W/cm2 of heat flux removal from the heat source with the heat dissipation area of 1 cm2. The measured value of the thermal resistance between the heat source and cooler surface under the module is 0.8 °C/W.

Влияние режимов замораживания, сроков хранения и способов дефростации на микробиологические показатели качества абрикосов

Introduction. Low-temperature freezing technology extends the shelf life of perishable fruits as it causes a sharp slowdown in the biochemical and microbiological processes in frozen products. However, it cannot provide complete destruction of microorganisms.
 The present research featured the reaction of apricot microbiota to the technological techniques of shock freezing. The research objective was to study the effect of low-temperature freezing modes (t = –25, –30, and –35°C), storage time (3 and 9 months), methods, and defrosting modes (in air at t = 5 and 22°C; in water at t = 5, 16, and 22°C; under the effect of microwave irradiation) on the surface microflora of apricots.
 Study objects and methods. The experiment featured apricots of the varieties Uzden, Untsukulskiy Pozdniy, Honobah, Krasnoshchyokiy, and Shalakh. The microbiological profile of defrosted apricots was based on the State Standard.
 Results and discussion. Fast freezing at t = –25°C provided a better inhibition of epiphytic microflora than at t = –30 and –35°C: aerobic-mesophilic and optionally anaerobic microorganisms – by 65.2–68.6%, yeast – by 61.5–69.0%, and mold – by 59.3–68.4%,
 compared to their initial content on fresh apricots. During the initial period of refrigeration storage, the number of microorganisms decreased, while the subsequent nine-month storage (t = –18°C) led to a slight increase in microbiota. After nine months of storage, the number of microorganisms on defrosted fruits, depending on the variety, was the following: aerobic-mesophilic and optionally anaerobic microorganisms – 1.2×103–2.0×103 CFU/g, yeast – 14–26 CFU/g, and molds – 75–108 CFU/g. Defrosting of apricots by microwave irradiation resulted in a greater destruction of microorganisms than after traditional thawing in air and water.
 Conclusion. The results of microbiological studies indicate that the shock freezing technology ensures the production of quick-frozen apricots that meet the requirements of Technical Regulations of the Customs Union No. 021/2011.

Electrodeposition of Dysprosium in pyrrolidinium triflate ionic liquid at ambient temperature: Unraveling system efficiency and impact of solvation interplays on the reduction process

Electrochemical reduction of rare earth elements (REEs) in ionic liquids (ILs) has attracted much attention, as a promising low temperature and alternative technology for molten salt electrolysis. While reported studies have established the proof of concept of the ionic liquid technology, efficient recovery and fundamental understanding of the electrodeposition process in these systems are still lacking. In this work, the reduction of dysprosium triflate (Dy(OTf)3) complex is investigated in neat pyrrolidinium triflate (BMPyOTf) ionic liquid, a commercial but poorly explored system in literature. Chronoamperometry and surface characterization (SEM-EDS, XPS and ICP-MS) demonstrated an efficient (~80%) electrochemical recovery of Dy metal, with deposition rates approaching 10 mg.h−1.cm−2 at 0.3 M metal concentration, small applied potentials (~-3 V Fc+/Fc) and ambient temperature (25 °C). Cyclic voltammetry revealed two main electrodeposition waves (Red1 and Red2), suggesting single 3e- reduction of two co-existent metal complexes with different coordination spheres, strongly (Red2) and weakly (Red1) coordinated metal complex with the ionic liquid triflate anions. This suggestion was supported by the vibrational (Mid-IR) analysis, where downshifts of the νas(SO) stretching mode were consistent with an evolution of weaker metal coordination at higher concentrations. Near-IR confirmed the evolution of speciation, from one main complex at low concentrations to a mixture of species at higher concentrations. Estimation of the speciation's distribution from deconvoluted NIR and semi-derivative traces indicated that voltammetric currents are controlled by bulk concentrations. While under coulometric conditions, the metal reduction seems to proceed via the IL-coordinated thermodynamics, due to enhanced anion concentrations at the electrochemical interface. Extended study to bistriflimide analogue systems revealed a distinct infrared signature for the IL-coordination and validated the correlation between the observed reduction processes and the speciation heterogeneity in these systems. The outcomes of this work demonstrate an efficient electrochemical recovery of Dy in triflate-based systems, while shedding the light on the impact of solvation and coordination interplays on the electrodeposition process of REEs in ionic liquids.

Innovative low temperature methods of milk whey processing

Reasonable use and waste-free deep processing of milk raw materials represent serious issues for the most milk processing companies. Therefore, processing of milk whey and manufacturing products of full biological value is a promising trend. Its resources are enormous, exceeding 5 million tons per year, although only 40 % are recycled throughout the country. In addition, this problem is of high environmental importance. Milk whey is a product of cheese, cottage cheese and casein manufacturing. The chemical composition of milk whey is unique owing to biologically active peptides of whey proteins, which participate in physiological processes of human body. It contains 50 % dry milk substances and about 200 types of different compounds. Up to date engineering and technology processes aimed at the dehydration offer a solution to the problem of whey processing. The paper reports on low temperature technologies used in whey processing to produce protein concentrate. When freezing out water, a nutritionally valuable protein casein and albumin mass are concentrated. The cryoconcentration of milk whey on the inner surface of a crystallizer was carried out at a temperature of the heat exchanging surface minus 4 ± 2 ° C. Chemical composition, physical, chemical, and organoleptic characteristics of the whey concentrate have been investigated. The chemical composition of the whey protein concentrate contains 20.19 % of dry substances, 12.80 % of protein, 2.87 % of whey proteins. The freezing out of water in the set conditions has brought about a 25-time increase of whey protein fraction. Therefore, a whey mass can be recommended as a source of animal protein in human diets.

40.3: Invited Paper: Low temperature and robust OTFT technology suitable for a range of current or voltage driven display applications

SID Symposium Digest of Technical PapersVolume 52, Issue S1 p. 277-278 Technical Sessions: Session 40: OE-A Joint Session (Printed Display)Free to Read 40.3: Invited Paper: Low temperature and robust OTFT technology suitable for a range of current or voltage driven display applications Simon D Ogier, Simon D Ogier CTO SmartKemSearch for more papers by this author Simon D Ogier, Simon D Ogier CTO SmartKemSearch for more papers by this author First published: 24 February 2021 https://doi.org/10.1002/sdtp.14459AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume52, IssueS1International Conference on Display Technology (ICDT 2020)February 2021Pages 277-278 RelatedInformation

Half-warm mix asphalt with emulsion. An experimental study on workability and mechanical performances

One of the major sustainability-related challenge facing materials for asphalt pavements is the energy consumption and the release of harmful and odorous fumes. Reductions in these emission levels have been progressively achieved by a number of cleaner and low-temperature technologies. Recently, a further step towards an improved road pavement sustainability is represented by the half-warm mix asphalt (HWMA) mixtures, which are produced between 70 °C and 100 °C without negatively affecting their final performances. Among these methodological approaches, a very interesting solution for urban or low volume traffic roads is represented by HWMA mixtures prepared with a conventional warm emulsion and heated aggregates. Although this technique is capable of combining the advantages of hot and cold mixes, limiting some drawbacks, it is still little known and remains confined only to some regional areas (in Spain with the term mezclas templadas). There are no standards or specifications, but only some construction practices resulting from the experience gained in the field. Thus, a laboratory-scale experimental study was set up to analyze in detail the behavior of dense-graded HWMA mixes prepared with emulsion intended for a surface course layer of a low or medium traffic road. The objective was to evaluate the influence of three mix-design variables, such as compaction temperature, binder content and aggregate gradation on the volumetric and mechanical, i.e. indirect tensile strength and moisture susceptibility, properties of these mixtures. The rank comparison between the selected mixtures represented the starting point for improving on the one hand the mix-design process and on the other the operational procedures of production, transportation and placement.

Trends in Low-Temperature Circuit Technology to Control Quantum Bits for Large-Scale Quantum Computers

Trends in Low-Temperature Circuit Technology to Control Quantum Bits for Large-Scale Quantum Computers

Research Progress of Low Temperature Plasma Technology to Treat Sulfur-containing Malodorous Gas

This paper briefly discusses the source, harm and removal methods of sulfur-containing malodorous gas. At this stage, the main methods for treating sulphur-containing malodorous gases are physical, chemical and biological methods. In contrast, low temperature plasma technology combines the advantages of physical, chemical and biological methods, and can effectively overcome the disadvantages of traditional processes. Through the comparison of various methods, the advantages of low temperature plasma treatment of sulfur-containing malodorous gas are summarized, and the corresponding removal mechanism is proposed. The treatment progress and existing problems of using low-temperature plasma to remove sulfur-containing malodorous gas, especially hydrogen sulfide, carbon disulfide, methyl sulfide, methyl mercaptan and dimethyl disulfide, are comprehensively discussed. A new idea for the simultaneous removal of multi-component sulfur-containing malodorous gas by low temperature plasma is proposed. Compared with traditional methods, low temperature plasma technology has the advantages of simple process, strong applicability, easy operation, and low energy consumption in processing sulfur-containing malodorous gases. The treatment of sulfur-containing malodorous gas by low-temperature plasma technology needs further research.

High-strength concrete technology for manufacturing reinforced concrete sleepers from prestressed reinforced concrete

The properties of concrete with complex chemical additives to improve the technology for the production of sleepers from prestressed concrete are discussed in the article. With the use of complex chemical additives under heat-moisture processing, at a temperature of 40°C, there was no decrease in the strength of the cement stone and sufficient strength at the initial stage of the curing period, 44.7 MPa; concrete strength was determined with the addition of Glenium 27 S - 1.0% and the hardening accelerator Master X -Seed 100 - 1.2%. Thus, the use of complex chemical additives makes it possible to solve the problem of achieving the necessary early high strength of concrete to implement low-temperature technology in the production of reinforced concrete sleepers.

Numerical simulation of highly efficient lead-free perovskite layers for the application of all-perovskite multi-junction solar cell

The numerical simulation of lead-free perovskite cesium tin germanium halide (CsSnGeI3) and methyl ammonium germanium halide (CH3NH3GeI3) solar cells have been performed. It has been elucidated from the numerical simulation that as compare to the CH3NH3GeI3 based structure, CsSnGeI3 based structure depicts better photovoltaic performance under constant illumination condition. To enhance the device photovoltaic performance, the effects of different hole transport layer (HTL), defect density of the absorber layer, metal work function and the effect of temperature has been studied. In the present investigation, the effect of hole transport layers are analyzed by correlating the built-in voltage (Vbi) with the open circuit voltage (VOC). It has been obtained from the simulation results, that Vbi has a significant impact on VOC as the higher Vbi corresponds to the highest VOC. Moreover, the effect of defect density and metal work function is also studied. It is obtained from the simulation results, that the optimum defect density is found to be 1 × 1014 cm−3 and metal work function should be greater than or equal to 5 eV for both lead-free CH3NH3GeI3 and CsSnGeI3 based perovskite layer. Furthermore, to suggest possible lead-free alternatives for all-perovskite two-terminal multi-junction solar cell, an attempt is made to match the current of bottom perovskite layer i.e., CsSnGeI3 based perovskite layer to the top perovskite layer i.e., CH3NH3GeI3 based perovskite layer. To attain the current matching for bottom perovskite layer (CsSnGeI3 based perovskite layer) to top perovskite layer (CH3NH3GeI3 based perovskite layer), the bottom perovskite sub cell is fed with the filtered spectrum which is obtained by transmission from top electrode. After, the realization of current matching the short circuit current density of CsSnGeI3 based perovskite layer drops from 25.75 mA/cm2 to 15.32 mA/cm2 which is similar to CH3NH3GeI3 based perovskite absorber layer. In addition, it has been obtained from literature, that both the perovskite layers can be fabricated using solution–processing low-temperature technology. Hence, the numerical study suggests the possible alternatives for wide and narrow bandgap perovskite layers for the application to obtain highly efficient lead-free all-perovskite multi-junction solar cells.

Development of energy-efficient techniques and technology for environmentally friendly microwave processing of oil sludge

Methods of processing hydrocarbon-containing waste, such as chemical, biological, thermal, physico-chemical, filtering and settling, centrifugation at low efficiency and a wider range of other disadvantages. One of the promising technologies in the oil industry is considered to be microwave heating of hydrocarbon compounds to reduce viscosity during transportation, separation of stable emulsions during primary oil refining, and utilization of drilling oil sludge and petrochemical production wastes. The results of the development of energy efficiency low-temperature technology for environmentally friendly microwave processing of hydrocarbon-containing waste are presented. Studies on a mathematical model showed that at a frequency of microwave radiation equal to the resonant frequency of water molecules, the field strength needed to break the emulsion is 2-100 V/m. For comparison, we note that microwave generators with a power of 50-100 kW are used for heating, respectively, the electric field is more than 10000 V/m, i.e. 100 times higher than required. The time required for phase separation imposes unacceptable requirements on the flow rate. In the studied microwave processing mode due to the resonant interaction of water dipoles with an electromagnetic field, the exposure time is determined by the value of 10-9-10-10 seconds. With these parameters, the temperature of hydrocarbon-containing waste, as shown by calculations on the mathematical model, remains practically unchanged. Due to short-term (microsecond) processing, this technology can be used in the process stream of primary processing and oil refineries, which will significantly reduce the amount of waste generated.

Foams based on industrial waste

Substantial volumes of tailings and waste rocks placed in dumps create serious environmental and economic damage in mining areas and adjacent territories. The development of technologies for processing waste into heat-insulating building materials (foam glass) will make it possible to reduce the burden on the environment, as well as reduce the cost of finished building products. The article substantiates the possibility of obtaining block foamed materials for the production of heat-insulating materials based on man-made waste using low-temperature technology. The author investigated the ways of improving the operational properties of foam silicates by introducing modifying additives (apatite-nepheline waste, fly ash). To obtain foam silicates based on silica-containing waste, a liquid glass composition was prepared, into which additives were introduced. After molding and drying, the samples were swollen. Physical, chemical and thermal properties of foamed silicate materials made of silica-containing raw materials were determined taking into account the requirements of GOST for thermal insulation construction materials. To determine the thermal conductivity coefficient, an ITP-MG 4 electronic thermal conductivity meter was used. Microscopic studies were carried out using a SEM LEO 420 scanning microscope. The author of the article proposes the optimal compositions and conditions for obtaining foam materials that meet the regulatory requirements for materials and products for building insulation. Foamed materials with density up to 0.55 g/cm3, strength 5.5 MPa, water absorption 15–22 %, thermal conductivity 0.09–0.104 W•m/K were obtained. Foam glass materials have a wide range of properties: non-flammable, environmentally friendly, have a long service life, and are not subject to mold deterioration. The obtained materials can be recommended for use as thermal insulation in the construction and reconstruction of industrial and civil buildings and structures.

Performance Comparison of Absorption Heat Pump and Refrigeration in Low Temperature Waste Heat Recovery

Absorption heat pump and absorption refrigeration cycle are widely used in industries as two of the most important low-temperature waste heat recovery technologies. In order to compare their energy and economic performances, this paper establishes the models of one effect LiBr –H2O absorption heat pump and one effect LiBr -H2O absorption refrigeration cycle in the process simulation software Aspen PLUS. The two systems are simulated for waste heat source under temperature from 95 (C to 125 (C saturated water to output 130 (C saturated steam (absorption heat pump), or 7 and 10 °C cold water (absorption refrigeration). The energy and economic performances of the two technologies are compared and analyzed through three parameters, coefficient of performance, exergy efficiency, and operation cost per unit exergy output. The results show that the performance of heat pump is better than that of refrigeration cycle under each of these evaluation indexes. The work in this paper aims to provide some theoretical support and technology selection suggestion for low temperature waste heat recovery.

Exothermic behavior and drying shrinkage of alkali-activated slag concrete by low temperature-preparation method

Certain drawbacks of alkali-activated slag (AAS) concrete, such as rapid reactions releasing substantial heat and higher drying shrinkage, limit its application in practice. This work investigated controlling the hardening temperature, shrinkage, and cracks by means of low-temperature preparation technology. The effects of different curing procedures on the hardening temperature, drying shrinkage, mechanical properties, and microstructures of AAS concretes were determined. The hardening temperature of the AAS concretes could be significantly reduced by using low-temperature preparation technology, which could improve the compressive strength of the NaOH- or 1.0 M waterglass-activated slag concretes, but had a slight adverse effect on the flexural strength. X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) results demonstrated that katoite phases and gypsum were generated from the NaOH activated slag concretes prepared by low-temperature technology, which was contributed to the reduction in the drying shrinkage. Meanwhile, the microcrack densities of the concretes prepared in this manner were significantly reduced.

Methods for Increasing the Speed of the Analog Interfaces for Physical Quantity Sensors Based on Radiation-Hardened and Low-Temperature Technologies

The main circuitry methods for improving dynamic parameters in the large signal operation of the analog sensor interfaces (ASI) used in the instrumentation and automatic control systems are compared in the article. It is shown that the existing methods for increasing the slew rate (SR) of the ASI based on the operational amplifier (OA) are associated with the increase in the gain-crossover frequency of the OA due to the higher-frequency technologies (i.e., SiGe), or with the expansion of the range of active operation of the input subcircuit included before the integrating capacitor of the OA. A method for increasing the SR of the inverting ASI with an OA input stage of the dual-input class is proposed. The basis of the method lies in the introduction of two differentiating correction circuits (DCC) into the classical OA circuit, which in the large signal operation form additional overcharge currents of the integrating capacitance of the OA correction. In this case, the DCCs practically do not affect the low-signal amplitude-frequency characteristic of the OA. Such OAs have low current consumption in static mode and can be performed on the basis of standard processes, including radiation-hardened and low-temperature ones (CMOS, SOI, SOS, BiJFet, BJT, SiGe and others). The BJT OA computer simulation results show that the inverting ASI SR increases from 170 to 1800 V/μs. We consider the promising architectures of the high-speed OAs with the DCCs providing an increase in the SR in both inverting and non-inverting ASIs. The proposed ASI circuitry is designed to be used in automation devices and control systems, including nuclear and energy facilities.