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Different heating processes were applied to pretreat the pulp and paper mill sludge to enhance the hydrolysis stage. Hot air oven, autoclave, microwave and water bath were used for comparison. Chemical analyses exposed that all the pretreatment methods have shown improvement in solubilisation of organic matter. Among the pretreatments studied, heat transfer through hot air (80 °C for 90 min) mode had the highest impact on sludge solubilisation. There was an increase in cellulose (P = 0.0096), acid soluble (P = 0.0053) and insoluble lignin (P = 0.0012), but decrease in hemicellulose (P = 0.0009) content after pretreatment. The XRD and FT-IR spectroscopic characterisation shows the development of aliphatic, unsaturated and carbonyl carbon functionalities in the pretreated samples at higher severities. FESEM picture also confirms the change in structure after pretreatment. Thus, pretreatments contribute to disruption of the lignocellulosic structure making the cellulose easily accessible to acidogenic microorganisms. [ABSTRACT FROM AUTHOR]

Smart materials promote the development of soft actuators. Herein, the modularized origami soft actuators consisting of shape memory alloy (SMA) wires, foldable paper‐based heaters, and paper substrates with special origami structures are proposed, which are connected without adhesive and allow convenient replacement for damaged parts. SMA wires are threaded into the paper as a drive module. The foldable paper‐based heaters with a length of 288 mm can be heated to 105.1 °C at 6.5 V to control the origami soft actuators. Combined with theoretical calculations and experimental measurements, the origami structure is adopted which exhibits a high recoverability compared with the flat structure because the design finds a structure–material balance by increasing structural flexural rigidity (2 times of that flat structure) for improving the restoring force while maintaining the deformation of materials within the elastic region during the actuation. The three modules in the origami actuator are independent and perform their functions individually. The combined system can also become a module that provides a driving force in other devices. This work provides a novel route and insight for developing modular soft actuators. [ABSTRACT FROM AUTHOR]

Density and hardness are physical parameters in the manufacturing of refuse derived fuel (RDF) pellets. In making pellets, a high heating value for the combustion system is desired. This research aimed to analyze the mixture of municipal solid waste to its density and hardness and study its correlation to heating value. The variable used in this research is a mixture of paper waste and garden waste and food scraps and garden waste. The density and hardness for the mix of paper waste and garden waste were 1970.6 to 2474.8 kg/m3 and 37.8-42.8 HA, respectively. The mixture of food waste and garden waste has density and hardness of 1822 to 2276.7 kg/m3 and 17.4-37.8 HA. The correlation between density and hardness on heating values did not reach a significance of 0.05, so there was no strong relationship between density and hardness on heating values. [ABSTRACT FROM AUTHOR]

In this study, a microwave plasma reactor was used for pyrolysis of waste papers. The effects of different argon flow rates on char and gas generation were investigated. Changes in carbon and oxygen contents from those in paper to char were significant. Char yield of over 25 % was obtained with the heating value of about 38 MJ/kg. Average gas yield and total content of combustible fraction (CO, CH4 and H2) in the gas product were 2.56 m3/kg and 36 %, respectively. The heating value of gas product and carbon conversion efficiency of the process were maximum at 6.0 MJ/m3 and 73 %, respectively. [ABSTRACT FROM AUTHOR]

A solution-processed conductive paper heater (CPH) with metallic features is used as a new class of low voltage ignitor of nanoenergetic materials (nEMs). In contrast to conventional electrothermal ignition techniques that typically require high operating voltages, the combustion of a paper substrate with a relatively low ignition point generates high thermal energy instantaneously, which makes it possible to ignite nEMs even at low voltages as low as ∼1 V. In addition, the ignition and explosion properties of CPH-based low voltage ignitors are highly controllable and reproducible, mainly due to their simple fabrication and reliable electrical properties. Based on the low voltage ignition property, a compact remote ignition system is demonstrated by integrating wireless a switching circuit, portable batteries, and heater mounter in a small plastic package and operated remotely to ignite the nEMs. [ABSTRACT FROM AUTHOR]

Copper sulfide deposition on cellulosic insulating materials in oil-immersed transformers is evaluated by heating tests stipulated by IEC 62535. Although this method is suitable for evaluation of the corrosivity of unused insulating oil, the subject remains in diagnosis of the insulating oil used. It is because dibenzyl disulfide (DBDS), which is the prime compounds that cause copper sulfide deposition, is consumed by the reaction with copper during operating of transformer. Therefore, it is necessary to detect the existence of DBDS in insulating oil diagnosed as non-corrosivity by IEC 62535. The proceeding paper [6] reports that Bibenzyl (BiBz) and Dibenzyl sulfide (DBS) will be formed in the insulating oil as by-products of copper sulfide formation between copper and DBDS in oxygen-poor atmosphere which imitated the closed-type transformers. These by-products are considered to be the indication of copper sulfide formation. However, the influence of oxygen and addition agent (e.g. 2,6-di-tert-butylp- cresol) on the mechanism of the by-product formation is unclear. The purpose of this study is to elucidate the influence of oxygen and DBPC in by-products formation for development of diagnosis. It became apparent that benzyl alcohol, benzaldehyde and benzoic acid generate as by-products of copper sulfide formation in the air atmosphere which imitated the open-breathing transformers. Furthermore, it became apparent that the reaction product of benzyl radical and the radical of DBPC generates as by-product of copper sulfide formation in the insulating oil containing DBPC. These by-products are detectable even if DBDS disappears. Therefore, it is thought that diagnosis of the open-breathing transformer is possible by detecting these by-products. [ABSTRACT FROM AUTHOR]

The suppressive effect of triazole-based passivators such as 1,2,3-benzotriazole (BTA) and Irgamet 39 and duration of the suppressive effect on copper sulfide deposition are investigated by changing the time when passivators are added to oil. All corrosive sulfur tests were performed by the method stipulated by IEC 62535. In order to simulate the timing for adding passivators into actual transformers, preheated and non-preheated oils were used for corrosive sulfur test. Adding a passivator into preheated oil simulates the condition where a passivator is added into the transformer after a period of operation, and adding a passivator into non-preheated oil simulates the condition where a passivator is added before operation. Although the deposition rate of copper sulfide in preheated oil with the addition of passivator was lower in preheated oil without passivator, copper sulfide deposition still continued even while the passivator was detected in the oil. The result suggests that the precursors of copper sulfide have been already generated in preheated oil before adding a passivator. After the passivator was depleted in the oil, the period until onset of copper sulfide deposition in the preheated oil was shorter than in non-preheated oil since a protective complex layer was created on the copper surface and reaction with the passivator continued to prevent the deposition of copper sulfide precursors. [ABSTRACT FROM AUTHOR]

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The temperature distribution is vital to the lifetime and reliability of converter transformer bushings. However, the temperature distribution of epoxy impregnated paper converter bushings under a certain current has usually been calculated through the two dimensional model, without considering the heat convection and radiation effects. In this paper, using the computational fluid dynamics (CFD) and finite element method (FEM) analysis, a 3-D electromagnetic-fluid-thermal analysis method has been proposed. With the considering of heat conduction, heat convection and radiation, the temperature distribution of the converter transformer bushing has been simulated according to the actual operating environment. The temperature and velocity distribution of the converter transformer bushing has been obtained. Moreover, the simulation results have been compared with the experimental results to verify the accuracy of the simulation method. The simulation results, especially for the inner conductor, external conductor and the epoxy impregnated paper, are very close to the experimental results and the maximum temperature difference percentage is within 10 %, which indicates the accuracy and effectiveness of the electromagnetic-fluid-thermal analysis method proposed. [ABSTRACT FROM AUTHOR]

Copper sulfide deposition on cellulosic insulating materials in oil-immersed transformers was investigated by heating tests stipulated by IEC 62535 with controlled atmospheres to which mineral insulating oils were exposed. Both oxygen in the atmosphere and 2,6-di-tert-butyl-p-cresol (DBPC) in the oil were found to accelerate the copper sulfide deposition on the insulating paper when the oil contains dibenzyl disulfide (DBDS). The weight of copper sulfide deposition on the insulating paper was found to increase when the oxygen concentration was increased up to 20 volume %. X-ray absorption near edge structure (XANES) analysis was applied to study the chemical bonding state of copper atoms in copper deposits on the insulating paper for the first time. It can be clarified the copper deposits on the insulating paper are mainly Cu2S and small amounts of CuO are contained. [ABSTRACT FROM PUBLISHER]

The hot spot temperature inside the windings of the oil-immersed power transformers may exceed 200 °C due to some winding deficiencies, posing negative impact on the paper insulation. A series of heating experiments are deliberately conducted with oil-paper insulation samples to study the influence of the hot spot temperature ranging from 120 to 280 °C, and the insulation degradation is characterized by the breakdown voltage (BDV) and the degree of polymerization (DP). Furthermore, surface morphology, water content and cellulose degradation mechanism are analyzed so as to reveal the causes of the above phenomena. The experimental results indicate that with increase of the hot spot temperature, the breakdown voltage increases after the first drop, while the DP continues to decline in the tested temperature range. No obvious linear relationship is observed between the hot spot temperature and the DP or the BDV. Regarding the test samples the authors have studied, the inflection point of the hot spot temperature for the insulation deterioration is found to be between 240 and 260 °C. The proposed research presents a fundamental reference for assessment of the winding insulation degradation from the viewpoint of hot spot temperature. [ABSTRACT FROM AUTHOR]

Power transformer is one of the most expensive equipments in a high voltage AC power system. Adequate monitoring system for power transformers can help in reducing the failure rate and thereby enhancing system reliability and economic efficiency. The failure of power transformer has serious consequences on system reliability. Long term and comprehensive testing cannot be done in working transformer, so prorated model of transformer is preferred. In the proposed work, a new dual temperature test cell is developed based on IEC 62332 and IEEE C57.100. The cell provides for a current carrying conductor wrapped with insulating paper and further insulation is provided with high-density pressboard as per arrangements in power transformer. In this paper a new mathematical model is developed using activation energy and preexponential constant calculated from experimental results at different temperatures. The expected life based on degree of polymerization (DP) value, shows nonlinear aging of insulation based on investigation carried out on prorated model. [ABSTRACT FROM AUTHOR]

Observed individual variability in cardiac baroreflex sensitivity (cBRS) and heart rate variability (HRV) is extensive, especially during exposure to stressors such as heat. A large part of the observed variation may be related to the reliability (consistency) of the measurement. We therefore examined the test-retest reliability of cBRS and HRV measurements on three separate occasions in 14 young men (age: 24 (SD 5) years), at rest and during whole-body heating (water-perfused suit) to raise and clamp oesophageal temperature 0.6°C, 1.2°C and 1.8°C above baseline. Beat-to-beat measurements of RR interval and systolic blood pressure (BP) were obtained for deriving HRV (from RR), and cBRS calculated via (i) the spontaneous method, α coefficients and transfer function analysis at each level of heat strain, and (ii) during forced oscillations via squat-stand manoeuvres (0.1 Hz) before and after heating. Absolute values and changes in all cBRS estimates were variable but generally consistent with reductions in parasympathetic activity. cBRS estimates demonstrated poor absolute reliability (coefficient of variation ≥25%), but relative reliability (intraclass correlation coefficient; ICC) of some frequency estimates was acceptable (ICC ≥0.70) during low-heat strain (ICC: 0.56-0.74). After heating, forced oscillations in BP demonstrated more favourable responses than spontaneous oscillations (better reliability, lower minimum detectable change). Absolute reliability of HRV estimates were poor, but relative reliability estimates were often acceptable (≥0.70). Our findings illustrate how measurement consistency of cardiac autonomic modulation estimates are altered during heat stress, and we demonstrate the possible implications on research design and data interpretation., (© 2020 The Authors. Experimental Physiology © 2020 The Physiological Society.)

Abstract: Carbon paper is commonly used as the gas diffusion layer (GDL) in polymer electrolyte membrane (PEM) fuel cells as it exhibits high chemical and mechanical durability. This diffusion medium is also anisotropic, which directly affects its transport properties and specifically the thermal conductivity. In this study, the in-plane thermal conductivity of the carbon paper GDL was determined using thermal diffusivity measurements for a temperature range from −20 to +120°C and four Teflon loadings (0, 5, 20 and 50wt.%). It is important to understand the effect of temperature on the thermal conductivity since PEM fuel cells are designed to operate under various temperatures depending on the application of use. Further, Teflon is used to change the hydrophobic properties of the carbon paper GDL with 20wt.% as the most widely used percentage. In this study, the Teflon loadings were chosen to gain a comprehensive understanding of the thermal resistance due to Teflon. In this study, a quasi-steady method was used to measure the thermal properties of the carbon paper; hence, the phase transformation in the presence of PTFE was investigated. The thermal conductivity decreases with an increase in temperature for all samples. The addition of as little as 5wt.% Teflon resulted in high thermal resistance decreasing the overall thermal conductivity of the sample. Further addition of Teflon did not have major effects on the thermal conductivity. For all treated samples, the thermal conductivity lies in the range of 10.1–14.7W/mK. Finally, empirical relations for the thermal diffusivity and conductivity with temperature were deduced. [Copyright &y& Elsevier]

In a search for mineral oil substitutes, we focus on silicone and ester oil. These insulating oils are fire-resistant and environmentally friendly. In previous studies, we investigated streaming electrification and dielectric breakdown phenomena in these new oils and found that their performance was similar to or better than that of mineral oil. In the present study, we focus on the thermal degradation of insulating oils. Thermal degradation tests in the presence of a solid insulator and copper carried out for 1000 h at 130 and 180 °C. Color changes, chemical analysis and dielectric breakdown characteristics were also investigated during thermal degradation of the insulating oils. We also investigated the mechanical strength of the solid insulator. The characteristics of aged oils were compared with those of fresh oils. Tested silicone oil presents better performance than esters and mechanical characteristics of paper remain unchanged in all resistance liquids. [ABSTRACT FROM AUTHOR]

The combined production of electricity and thermal energy (combined heat and power or co-generation) is the most efficient and convenient approach to reduce costs for energy at industrial power plants and district heating plants that use natural gas as fuel to produce thermal energy for various needs. This paper analyses the operational characteristics of the combined heat and power plant, which has been operating since January 1, 2021, at the Voždovac Heating Plant as part of the Belgrade district heating system. The combined heat and power plant consists of three gas engine units with a total nominal electric power of 10 MW and thermal power of 10.1 MW, which use natural gas as fuel. The combined heat and power plant is used for district heating and preparing domestic hot water while electricity is sold to the local electric grid. The analysis in this paper focuses on the plant's operational characteristics: the number of working hours, the total energy consumption and energy production, the efficiency as well as the operational and maintenance costs. Also, the impact of the drastic changes in the prices of natural gas, electricity, and maintenance costs in the last year on the financial profitability of the combined heat and power plant was analysed in particular. [ABSTRACT FROM AUTHOR]

The power transformer is one of the most important equipment in the electrical power system due to its cost and potential failure????s consequences. To ensure a continuous energy supply, it is needed to assess abnormal condition such as thermal and electrical behavior. From this viewpoint, dissolved gas analysis (DGA) is very useful in detecting internal defects in oil-filled electrical equipment. A system has been developed that allows to simulate partial discharge and overheating in transformer????s insulation. By using this system, we have studied on DGA under low temperature overheating in mineral oil and vegetable oil. [ABSTRACT FROM AUTHOR]

For more than a century, conventional mineral oil/cellulose insulation is being used as main insulation for power transformers. The life span of these major assets is determined amongst others by the insulation system?s mechanical resistance to withstand short circuit current forces. Since cellulose paper aging is accelerated by temperature, moisture and oxygen, poly-aramid-based synthetic insulation paper, with better thermal stability emerged for application in transformers. However the relatively limited number of studies on hybrid insulation and the cost of aramid paper still limit their use in distribution transformers. This contribution attempts to demonstrate that despite the high cost of aramid paper, hybrid insulation could be used in large power transformers which represent a significant financial investment. To do this, the quality of mineral oil aged with hybrid solid insulation and the thermal aging of the cellulose paper of this insulation are investigated. Comparison was made with traditional mineral oil impregnated cellulose paper to provide a benchmark for comparison. The samples underwent thermal accelerated aging procedure according to ASTM-D1934 standard and, furthermore, were submitted to local overheating. The condition of oil samples collected from each aging vessel was assessed using several diagnostic techniques, namely the relative amount of the Dissolved Decay Products (DDP), Turbidity, and Interfacial Tension (IFT). The Degree of Polymerisation (DPv) and Dissolved gas Analysis (DGA) were used to monitor the thermal aging of the cellulose paper samples. The results indicate that oil aged with hybrid solid insulation yield fewer decay products at some aging stages, especially after the application of a local overheating. The results also indicate that the cellulose paper within solid hybrid insulation is slightly less degraded compared to that of conventional insulation. [ABSTRACT FROM AUTHOR]

Copper sulfide deposition on Kraft paper in oil-immersed transformers is found to be accelerated by di-tert-butyl p-cresol (DBPC), which is widely used as an antioxidant, and paraffinic hydrocarbons in their oils, which is verified in laboratory experiments. DBPC can prolong the lifetime of precursors of the copper sulfide deposition by reacting decomposition products of copper dibenzyl disulfide (Cu-DBDS) complex and by creating the Cu-DBPC complex. Because the lifetime of the Cu-DBPC complex is far longer than that of the Cu-DBDS complex, considerable amounts of copper sulfide are deposited on Kraft paper instead of being formed on the surface of copper. A good correlation is obtained between the concentration of paraffinic hydrocarbons and the amount of copper sulfide deposited on Kraft paper in the three commercial oils. [ABSTRACT FROM PUBLISHER]

In order to understand the application of iot Big data information acquisition for heating control systems, a research on iot Big data information acquisition for thermal storage heating control systems is proposed. This paper first analyzes the shortcomings of the traditional heating system, the heating data is scattered and difficult to collect. The IoT technology is applied to the heating platform through data acquisition, data visualization, data mining, data management and other aspects. Secondly, the application of the IoT in heating system data acquisition is studied, including the types of heating data collected, data acquisition process, data acquisition standards, etc. Finally, this paper takes the energy-saving transformation of 26 boilers in a heating enterprise as an example. The research results show that the boiler efficiency obtained in real time by using the online monitoring system of this project is 95.36%, and the reverse balance boiler efficiency in the paper report of the special inspection office is 94.88%, with a deviation of 1.48%. The application of the IoT technology can obtain the boiler indicators in real time and effectively, and can realize the comprehensive analysis of the monitoring data, and realize the evaluation of the energy efficiency operation state of the gas boiler and the fault diagnosis and early warning. The IoT technology is an effective means of fine energy-saving management in heating enterprises. [ABSTRACT FROM AUTHOR]

The Qinghai–Tibet plateau, with an average altitude of over 4000 m, has low annual average temperatures and a high demand for building heating. This region's abundant solar energy resources hold substantial practical significance for improving the indoor heat environment and reducing building energy consumption. This paper investigates the impact of orientation and skylight area ratio on building heat load and indoor temperature, using both actual measurement and simulation methods, with a case study of the comprehensive building at Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment (Beiluhe Station), located in the Qinghai–Tibet Plateau region. Initially, a model was established using the EnergyPlus 9.4 software, with orientation variables set from east to west in 15° increments, to simulate the variations in building heat load resulting from orientation changes; simulations were then conducted for three different skylight area ratios under the optimal orientation to evaluate their influence on heat load and indoor temperature. The results show that for the architectural style examined in this paper, the optimal building orientation within the region is 30° south by east, with the optimal orientation range spanning from 45° south by east to due south. Heating load is negatively correlated with the skylight area ratio, and beyond a certain threshold, the rate of decrease in heat load diminishes or even stabilizes. The conclusions of this paper offer guidance for the orientation and skylight design of new buildings on the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Concerning energy waste and rational use, this paper studies the optimal scheduling of day-ahead energy supply and the community's demand with a combined cooling, heating, and power (CCHP) system in summer. From the perspective of bilateral costs and renewable energy use, this paper examines the impact of energy storage systems integrated into cogeneration systems. The Gurobi solver is used to optimize the residential community's supply and demand sides of the traditional CCHP system (T-CCHP) and the CCHP system with energy storage (CCHP-ESS) under insufficient solar power. Subsequently, two optimal arrangements for energy consumption on the user side under these systems are suggested. In the optimization model, energy storage is added to the T-CCHP system on the energy supply side. On the user side, the energy use scheme is optimized considering the user's comfort. The innovation point of this study is that the optimization of comprehensive energy in the park involves both supply and demand. The impact of increasing energy storage is discussed on the energy supply side, and the impact of optimization of the energy use plan on costs is discussed on the user side. [ABSTRACT FROM AUTHOR]

This paper summarizes the results of a Special Issue focusing on the practical applications of model predictive control and other advanced control methods in the built environment. This Special Issue contains eleven publications and deals with various topics such as the virtual sensing of indoor air pollutants and prediction models for indoor air temperature and building heating and cooling loads, as well as local and supervisory control strategies. The last three publications tackle the predictive maintenance of chilled water systems. Most of these publications are field demonstrations of advanced control solutions or promising methodologies to facilitate the adoption of such control strategies, and they deal with existing buildings. The Special Issue also contains two review papers that provide a comprehensive overview of practical challenges, opportunities, and solutions to improve building operations. This article concludes with a discussion of the perspectives of advanced controls in the built environment and the increasing importance of data-driven solutions. [ABSTRACT FROM AUTHOR]

This paper aims to provide discernment toward establishing a general framework, dedicated to data analysis and forecasting in smart buildings. It constitutes an industrial return of experience from an industrialist specializing in IoT supported by the academic world. With the necessary improvement of energy efficiency, discernment is paramount for facility managers to optimize daily operations and prioritize renovation work in the building sector. With the scale of buildings and the complexity of Heating, Ventilation, and Air Conditioning (HVAC) systems, the use of artificial intelligence is deemed the cheapest tool, holding the highest potential, even if it requires IoT sensors and a deluge of data to establish genuine models. However, the wide variety of buildings, users, and data hinders the development of industrial solutions, as specific studies often lack relevance to analyze other buildings, possibly with different types of data monitored. The relevance of the modeling can also disappear over time, as buildings are dynamic systems evolving with their use. In this paper, we propose to study the forecasting ability of the widely used Long Short-Term Memory (LSTM) network algorithm, which is well-designed for time series modeling, across an instrumented building. In this way, we considered the consistency of the performances for several issues as we compared to the cases with no prediction, which is lacking in the literature. The insight provided let us examine the quality of AI models and the quality of data needed in forecasting tasks. Finally, we deduced that efficient models and smart choices about data allow meaningful insight into developing time series modeling frameworks for smart buildings. For reproducibility concerns, we also provide our raw data, which came from one "real" smart building, as well as significant information regarding this building. In summary, our research aims to develop a methodology for exploring, analyzing, and modeling data from the smart buildings sector. Based on our experiment on forecasting temperature sensor measurements, we found that a bigger AI model (1) does not always imply a longer time in training and (2) can have little impact on accuracy and (3) using more features is tied to data processing order. We also observed that providing more data is irrelevant without a deep understanding of the problem physics. [ABSTRACT FROM AUTHOR]

An isothermal microcalorimeter has been used to study ageing of oil impregnated kraft paper. Under the assumption that the heat flow is proportional to the ageing rate of paper it is found that activation energy seems to be lower for oxidation than for hydrolysis. This observation corresponds well with results obtained by traditional ageing methods. The results have also been confirmed by measuring the changes in DP of the samples used in the calorimetric measurements. Comparing degradation of aged and unaged oil impregnated paper in air gave a higher heat flow for the unaged paper, but the activation energy for the processes remained the same. The process was also studied with another cellulosic material and in addition varying size of the sample holder of the calorimeter, giving similar results. Hence, since the microcalorimeter appears to give the same qualitative ageing characteristics for oxidation and hydrolysis as more time consuming methods, calorimeter could be a useful tool for quick ageing investigations. [ABSTRACT FROM PUBLISHER]

The ability to simultaneously heat and image samples using transmitted light is crucial for several biological applications. However, existing techniques such as heated stage microscopes, thermal cyclers equipped with imaging capabilities, or non-contact heating systems are often bulky, expensive, and complex. This work presents the development and characterization of a Miniaturized Optically-clear Thermal Enclosure (MOTE) system—an open-source, inexpensive, and low-powered modular system—capable of convectively heating samples while simultaneously imaging them with transmitted light. We develop and validate a computational fluid dynamics (CFD) model to design and optimize the heating chamber. The model simulates velocity and temperature profiles within the heating chamber for various chamber materials and sizes. The computational model yielded an optimal chamber dimension capable of achieving a stable temperature ranging from ambient to 95 °C with a spatial discrepancy of less than 1.5 °C, utilizing less than 8.5 W of power. The dual-functionality of the MOTE system, enabling synchronous heating and transmitted light imaging, was demonstrated through the successful execution of paper-based LAMP reactions to detect λ DNA samples in real-time down to 10 copies/µL of the target concentration. The MOTE system offers a promising and flexible platform for various applications, from molecular diagnostics to biochemical analyses, cell biology, genomics, and education. [ABSTRACT FROM AUTHOR]

The efficient utilization of waste heat from industrial processes can provide a significant source of energy savings for production plants, as well as be a driver of sustainable operations and the abatement of emissions. Industrial waste heat usually is contained in liquid or gaseous outlet streams. Although the possible ways to utilize waste heat are discussed in a wide variety of papers, these either provide only a general overview of utilization options and opportunities or focus on a narrow range of industrial processes. The aim of the present paper is to discuss the practical aspects of waste heat utilization in the European Union so that the reader can gain perspective on (i) the thermal classification of waste heat, (ii) liquid and gaseous waste streams and their typical temperatures for industrial use cases, (iii) the technical, economic, physical, and environmental aspects barring full utilization of the available waste heat, (iv) waste heat sources in various industries, and (v) standardized equipment and technologies applicable to industrial waste heat utilization, including their advantages, disadvantages, and weak points. [ABSTRACT FROM AUTHOR]

To optimize the energy supply potential and complementary advantages of distributed energy, this paper focuses on the dispatching optimization of cogeneration virtual power plant considering uncertainty. First of all, wind power, photovoltaic, combined heat and power (CHP) units, electric boilers, and controllable loads are integrated into a CHP virtual power plant. Then, carbon capture and electric-to-gas devices are introduced to realize carbon recycling. Furthermore, quantify the risk of real-time dispatching of virtual power plants through uncertainty scenario generation and conditional value at risk (CVaR) theory, and the multi-objective stochastic dispatching optimization model of virtual power plants is built with the aim at minimizing the operation cost, carbon emissions, and operation risk as the objectives, and the CRITIC weighting method is adopted to solve it. Finally, the calculation results show that: 1) the electric boiler can use wind and photovoltaic power to supply heat for the system, reduce the dependence ofthe virtual power plant (VPP) on the CHP unit, and make the electric output of the unit more flexible. 2) The risk quantification method proposed can fully measure the risk situation in real-time dispatching, arrange the wind and photovoltaic power generation plan and backup plan more reasonably, and enable the VPP to get more benefits while avoiding the risks in real-time dispatching. [ABSTRACT FROM AUTHOR]

Due to an urgent need to reduce the fast-progressing climate changes, a rapid, standardized and replicable solution for the infrastructure restructuring of the heat demand coverage of buildings at the district and city levels must be developed. As more and more communities in Europe, especially in Germany, are obligated to have plans for coverage of the heat demand, city planners and energy agencies seek a tool that will help them to design the first drafts of heating network routes, which can supply whole districts and cities with renewable energy. ArcGIS Pro Tools like Least-Cost-Path Analysis (LCPA) and Closest Facility (CF) allow us to find the shortest and "cheapest" way between the heat source and heat consumers in the analyzed areas. Starting from the community level, through the district, county, voivodeship and whole-country levels, the replication of the methods for generating district heating (DH) network infrastructure can be achieved. The proposed LCPA- and CF-based methods help to design the most suitable and efficient DH networks in the analyzed areas. As only a few open-source data inputs, like street networks and building footprints, are needed, the methods can be implemented in all communities in the country of Poland. In this paper, one example of one community in Wroclaw county, called Siechnice, and its surroundings is presented. [ABSTRACT FROM AUTHOR]

In view of the prominent and intractable problems of frequent high temperature alarms of the communication equipment and high energy consumption of air conditioners in Zhengzhou communication outdoor cabinets, a temperature control system with heat pipe as the main part and air conditioner as the auxiliary part is proposed in this paper. A prototype is developed and its applications are discussed. The annual field test shows the system works well, and it has a remarkable energy saving efficiency. [ABSTRACT FROM AUTHOR]

Due to the serious problems with energy efficiency, carbon emissions, and thermal comfort of rural residences in northern China, an optimization of active and passive heating technologies for rural residences is necessary. In this paper, an optimization for rural residences in northern China is conducted with four objectives: the whole life cycle carbon emission; the annual energy consumption through heating, ventilation, and air conditioning systems; the annual cost; and thermal comfort. In addition, the optimization model with active–passive heating technology synergy is resolved by NSGA-II genetic algorithm. The active and passive design variables, including the type of air source heat pump, orientation, the type and thickness of envelope insulation, the layer of window glass, the window-to-wall area ratio, as well as sunspace parameters are preferred to obtain the optimal solution. The results indicate that the optimal solution obtained by the ideal point method gives the most outstanding performance. Compared with the prototype, the optimized carbon emissions in severe cold and cold regions decreased by 56.1% and 54.6%, respectively. The annual energy consumption decreased by 59.7% and 62.2%. Finally, the roof insulation thickness is the most sensitive design variable in Pareto-optimal solution sets. This paper offers significant guidance in the application of the optimization method of active–passive technology synergy to the energy-saving design of buildings. [ABSTRACT FROM AUTHOR]

Digital polymerase chain reaction (dPCR) is extensively used for highly sensitive disease diagnosis due to its single-molecule detection ability. However, current dPCR systems require intricate DNA sample distribution, rely on cumbersome external heaters, and exhibit sluggish thermal cycling, hampering efficiency and speed of the dPCR process. Herein, we presented the development of a microwell array based dPCR system featuring an integrated self-heating dPCR chip. By utilizing hydrodynamic and electrothermal simulations, the chip's structure is optimized, resulting in improved partitioning within microwells and uniform thermal distribution. Through strategic hydrophilic/hydrophobic modifications on the chip's surface, we effectively secured the compartmentalization of sample within the microwells by employing an overlaying oil phase, which renders homogeneity and independence of samples in the microwells. To achieve precise, stable, uniform, and rapid self-heating of the chip, the ITO heating layer and the temperature control algorithm are deliberately designed. With a capacity of 22,500 microwells that can be easily expanded, the system successfully quantified EGFR plasmid solutions, exhibiting a dynamic linear range of 10 5 and a detection limit of 10 copies per reaction. To further validate its performance, we employed the dPCR platform for quantitative detection of BCR-ABL1 mutation gene fragments, where its performance was compared against the QuantStudio 3D, and the self-heating dPCR system demonstrated similar analytical accuracy to the commercial dPCR system. Notably, the individual chip is produced on a semiconductor manufacturing line, benefiting from mass production capabilities, so the chips are cost-effective and conducive to widespread adoption and accessibility., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The article talks about the reliability of electronic devices as an issue for technology, impact of Bias Temperature Instability on CMOS logic devices and evolving Hot Carrier Degradation and Self Heating Effect. It talks about degradation of program window, development in the field of device reliability and topics that includes Advanced Transistors, Gate Dielectrics and Memory Devices.

Modernizing existing buildings is vital to saving carbon emissions and counteracting global climate change. Many countries face the challenge of modernizing a considerable number of their buildings in the next two decades. Implementing related modernization measures requires a high number of craftworkers. However, current studies indicate that these craftworkers' current lack will increase. Examining the effects of craftworkers shortage on modernization strategies needs data concerning the realization time of modernization measures. We collected this data based on 90 expert interviews and provide it in this paper. The interview results comprise realization times for insulation measures of the envelope and changes in the heat supply system for typical buildings. This paper describes the data collection and presents the raw data available at a repository at Figshare. The data is internationally applicable in simulation and optimization approaches for building modernization. [ABSTRACT FROM AUTHOR]

This paper summarises the results of an experimental campaign carried out at SIET on the ELSMOR facility built in 2022 to validate a decay heat removal system for the E-SMR. Based on the passive mechanisms of natural circulation, the system aims to dissipate the reactor decay heat to a water pool, using two heat exchangers: a plate-type one coupling the primary side to the secondary side, and a vertical tube one coupling the secondary side to the water pool. Such a system is considered to be the most effective passive system, capable of safely managing the SMR accident and accidental situations, and achieving long-term decay heat removal without the need for electricity or external inputs. A description of the primary and secondary loops of the plant is given, together with the installed instrumentation and data acquisition system. In addition, the paper summarises the tests performed in terms of test procedures, test type and associated objectives, test matrix, test results, achievements, and open issues. [ABSTRACT FROM AUTHOR]

Various heating disturbances and faults in the heating network are necessary to be controlled and handled by some intelligent heating strategies with the increasing complexity of the heating network. This paper constructed the dynamic modeling of the heating system using standard thermal resistance and obtained a dynamic heat current model of the heating system. On this basis, we analyzed the heat transfer performance of the heating system. Five disturbances are selected, including the behavior of users, indoor heat source, heat exchanger heat transfer performance deterioration, pipe blockage, and pipe leakage. The effects of different disturbances on the overall system and user side water supply temperature were obtained by establishing a dynamic model for segmented heating pipelines. Feasible control methods for the heating network and load side are sorted out, mainly changing the water supply's temperature and the water supply's flow rate to reduce the water supply's fluctuation. Five specific control strategies are proposed for five types of disturbances. Comparing the case without control and the case with control, the results show that the fluctuation of water supply temperature is significantly reduced, and the control strategies can reduce the impact of disturbances on the heat network system and customers and improve the comfort of customers in the presence of disturbances. under the disturbance of pipeline leakage, the method proposed in this article reduces the temperature fluctuation amplitude by 75% and the fluctuation duration by 60%. [ABSTRACT FROM AUTHOR]