Effect Of Temperature Research Articles

Revisit of electron temperature effect on stimulated Brillouin scattering in homogenous plasma

Stimulated Brillouin scattering (SBS) has complex dependence on the plasma electron temperature via the Landau damping, particle trapping, and consequent nonlinear frequency shift. It is found from our numerical simulation that the SBS reflectivity in its saturation stage tends to increase with the plasma electron temperature within a certain range, although the linear growth rate of SBS normally reduces with the increasing electron temperature. This is because the phase velocity of an ion acoustic wave (IAW) increases with the electron temperature, which tends to reduce the Landau damping of the IAWs and hence reduce ion trapping. In the nonlinear saturation stage, ion trapping will modify the ion distribution function and induce a negative frequency shift in the IAW. This nonlinear frequency shift will break the three-wave coupling, thereby causing saturation of the SBS. With further increase in the electron temperature, however, electron trapping will dominate over ion trapping, which induces a positive frequency shift in the IAW and can lead to the SBS saturation as well. As a result, the SBS reflectivity first increases and then decreases with increase in the electron temperature. At around the peak of the SBS reflectivity, the positive frequency shift of IAW induced by electron trapping roughly offsets the negative frequency shift induced by ion trapping.

Comparative analysis of single-axis solar tracker performance with and without reflector under various weather conditions

This research explores a sun tracking system for solar panels that affects the power output of the panels. To address this, a unidirectional sun tracking system is implemented to ensure the solar panels are perpendicular to the sun, thus optimizing solar radiation. Additionally, reflectors are integrated to capture more sunlight. This research aims to design the system of unidirectional sun tracking to enhance the power output generated by solar panels and compare its performance with stationary (static) solar panels. The results demonstrate that the system of sun tracking improves the power output of solar panels. However, when reflectors are used in conjunction with the sun tracking system, no significant increase in power output is observed. Moreover, solar panels equipped with the unidirectional sun tracking system exhibit a power increase of 52.06 Watts compared to stationary solar panels. This research indicates that employing a unidirectional sun tracking system with the addition of reflectors does not enhance power output but instead reduces it due to the increased temperature effect caused by the sunlight reflection from the added reflectors.

Infrared thermography techniques for boundary layer state visualisation

The rapid decarbonisation of the power generation and aviation sectors will require a move away from incremental development, exposing designers and researchers to the risk of unexpected results from uncertainty in boundary layer state. This problem already exists for parts developed with fully turbulent assumptions, but in novel design spaces the risk increases for both real components, where previous knowledge of similar designs may be inapplicable, and particularly in experimental testing of scaled models, where reducing Reynolds number can result in a drastic change in flow topology that skews the conclusions of a test. Computational methods struggle to reliably predict boundary layer state so experimental techniques for diagnosing boundary layer state are needed. Infrared thermography (IR) is a non-invasive technique that offers simple, fast visualisation of boundary layer state with no additional instrumentation. IR is relatively uncommon in the literature and there is minimal information available on the best practices for its use. This paper aims to encourage the adoption of IR as a diagnostic tool by demonstrating routes for optimisation and pointing out pitfalls to avoid. A low-order model is developed and used to predict how the signal-to-noise ratio (SNR) of an IR visualisation changes depending on the thermal design of the test piece. It is shown that in low-speed flows with active heating from the surface the SNR is maximised through a suitable choice of surface insulation, while in high-speed flows, where passive temperature differences are used, there is a crossover between heat transfer and recovery temperature effects that results in an SNR of zero, an effect that can arise in both steady-state and transient experiments. Experimental validation of the 1D model in both flow regimes is shown alongside two case studies on the use of IR in sub-scale testing where uncertainty in boundary layer state results in critical differences from the full-scale flow.

Modeling the effect of ambient temperature on reticulorumen temperature, and drinking and eating behaviors of late-lactation dairy cows during colder seasons

Dairy cows may suffer thermal stress during the colder seasons especially due to their open-air housing systems. Free water temperature (FWT) and feed temperature (FT) are dependent on ambient temperature (AT) and can be critical for maintaining body and reticulorumen temperature (RT) in cold conditions. The objective of this study was to determine the effects of FWT and FT on RT fluctuations, and of AT on RT and drinking and eating behaviors in late-lactation cows during cold exposure. Data were collected from 16 multiparous lactating cows for four 6-d periods during the autumn and winter seasons. The cows (224 ± 36 days in milk; mean ± SD) had an average milk yield (MY) of 24.8 ± 4.97 kg/d and RT of 38.84 ± 0.163 °C. Daily average AT ranged from 4.38 to 17.25 °C. The effects of the temperature and amount of the ingested water or feed on RT change and recovery time, and the effect of the daily AT on RT, feed and water intake, and drinking, eating, and rumination behaviors were analyzed using the generalized additive mixed model framework. Reticulorumen temperature change and recovery time were affected by FWT (+0.0596 °C/°C and −1.27 min/°C, respectively), but not by FT. The amount of the ingested free water and feed affected RT change (−0.108 °C/kg drink size and −0.150 °C/kg meal size, respectively), and RT recovery time (+2.13 min/kg drink size and + 3.71 min/kg meal size, respectively). Colder AT decreased RT by 0.0151 °C/°C between 9.91 and 17.25 °C AT. Cows increased DM intake (DMI) by 0.365 kg/d per 1 °C drop in AT below 10.63 °C, but with no increase in MY. In fact, MY:DMI decreased by 0.0106/°C as AT dropped from 17.25 to 4.38 °C. Free water intake (FWI) was reduced by 0.0856 FWI:DMI/°C as AT decreased from 17.25 to 8.27 °C. Cold exposure influenced animal behavior with fewer drink and meal bouts (−0.432 and −0.290 bouts/d, respectively), larger drink sizes (+0.100 kg/bout), and shorter rumination time (−5.31 min/d) per 1 °C decrease in AT from 17.25 °C to 8.77, 12.53, 4.38, and 10.32 °C, respectively. In conclusion, exposure to low AT increased feed intake, reduced water intake, and changes in eating, drinking and rumination behaviors of dairy cows in late lactation. Additionally, the consequences of cold exposure on cows may be aggravated by ingestion of feed and free water at temperatures lower than the body, potentially impacting feed efficiency due to the extra energetic cost of thermoregulation.

The synergistic effect of high temperature and relative humidity on non-accidental deaths at different urbanization levels

Numerous studies have examined the impact of temperature on mortality, yet research on the combined effect of temperature and humidity on non-accidental deaths remains limited. This study investigates the synergistic impact of high temperature and humidity on non-accidental deaths in China, assessing the influence of urban development and urbanization level. Utilizing the distributed lag nonlinear model (DLNM) of quasi-Poisson regression, we analyzed the relationship between Wet Bulb Globe Temperature (WBGT) and non-accidental deaths in 30 Chinese cities from 2010 to 2016, including Guangzhou during 2012–2016. We stratified temperature and humidity across these cities to evaluate the influence of varying humidity levels on deaths under high temperatures. Then, we graded the duration of heat and humidity in these cities to assess the impact of deaths with different durations. Additionally, the cities were categorized based on gross domestic product (GDP), and a vulnerability index was calculated to examine the impact of urban development and urbanization level on non-accidental deaths. Our findings reveal a pronounced synergistic effect of high temperature and humidity on non-accidental deaths, particularly at elevated humidity levels. The synergies of high temperature and humidity are extremely complex. Moreover, the longer the duration of high temperature and humidity, the higher the risk of non-accidental death. Furthermore, areas with higher urbanization exhibited lower relative risks (RR) associated with the synergistic effects of heat and humidity. Consequently, it is imperative to focus on damp-heat related mortality among vulnerable populations in less developed regions.

Effect of sintering temperature on ratcheting-fatigue behavior of nanosilver sintered lap shear joint

Purpose The paper aims to study the effect of sintering temperature on the microstructure, shear strength and ratcheting fatigue life of nanosilver sintered lap shear joint. In addition, the Gerber model is used to predict the ratcheting fatigue lives of nanosilver sintered lap shear joints at different sintering temperatures. Design/methodology/approach In this paper, the nanosilver sintered lap shear joints were prepared at three sintering temperatures of 250 °C, 280 °C and 310 °C. The bonding quality was characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscope and shear tests, and the long-term reliability was studied by conducting ratcheting fatigue tests. In addition, three modified models based on Basquin equation were used to predict the ratcheting fatigue life of nanosilver sintered lap shear joint and their accuracies were evaluated. Findings When the sintering temperature is 250°C, the nanosilver sintered lap shear joint shows the porosity of 22.9 ± 1.6 %, and the shear strength of 22.3 ± 2.4 MPa. Raising the sintering temperature enhances silver crystallite size, strengthens sintering necks, thus improves shear strength and ratcheting fatigue life in joints. In addition, the ratcheting fatigue lives of the joints sintered at different temperatures are effectively predicted by three equivalent force models, and the Gerber model shows the highest life prediction accuracy. Research limitations/implications The sintered silver bondline is suffering a complex stress state. The study only takes the shear stress into consideration. The tensile stress and the combination of shear stress and tensile stress can to be considered in the future study. Practical implications The paper provides the experimental and theoretical support for robust bonding and long-term reliability of sintered silver structure. Social implications The introduced model can predict the ratcheting fatigue lives of the joints sintered at different temperatures, which shows a potential in engineering applications. Originality/value The study revealed the relationship between the sintering temperature and the microstructure, the shear strength and the ratcheting fatigue life of the joint. In addition, the Gerber model can predict the ratcheting fatigue life accurately at different sintering temperatures.

Extraction, catalytic study and milk-clotting properties of proteases from Brassicaoleracea

Proteases were extracted and biochemically characterized from different Brassica oleracea varieties (B. oleracea var. palmifolia (black cabbage, BC), B. oleracea var. sabellica (curly kale, K), and B. oleracea var. botrytis (white cauliflower, WC)). Calf rennet (CR) and Cynara cardunculus crude extracts (CC) were used as reference samples. The catalytic study used two different substrates: the synthetic peptide Bz-Phe-Val-Arg-pNA (BPVA-pNA), which contains para-nitroaniline (pNA), and azocasein (AzC) as a macromolecular substrate. The effect of temperature and pH on the proteolytic activity were also evaluated. Brassica proteases were further proposed as milk coagulants, and their coagulating efficiencies were evaluated. Bovine casein was incubated with the plant extracts, and the relative breakdown products were observed through electrophoresis. BC, K, and WC contain proteases which hydrolyze the macromolecular substrate (AzC) and synthetic peptides with Arg in P-1 (BPVA-pNA). Therefore, among the three B. oleracea varieties and control extracts, K leaf extracts displayed greater catalytic efficiency against AzC. Brassica extracts showed a lesser milk clotting index but visible milk curd formation. More importantly, the protease activities of BC and K extracts exhibited great catalytic activity over a broad range of pH (3.6–9.0) and temperatures (40–70 °C) using AzC as a substrate. Current pH and thermal tolerance results indicate that B. oleracea var. palmifolia and B. oleracea var. sabellica proteases could have broad applications in food technology. Many plant resources, which could represent potential sources of efficient proteases, are still unexploited.

Influence of annealing temperature and laser irradiation on the structural, optical, and photoluminescence characteristics of Ni2O3/SnO2 nanocomposites for perspective applications

In this study, a new approach methodology is employed to modify the structural, optical, and photoluminescence properties of Ni2O3/SnO2(NO/TO) nanocomposites. The effects of temperature and laser irradiation on a specific system were analyzed and described using XRD, XPS, and TEM. The diffraction patterns indicate the presence of two distinct phases within the NO/TO system. The XPS results reveal a robust underlying interaction between Ni2O3 and SnO2, exhibited by the observed shifts in the peak positions of Ni 2p, Sn 3d, and O 1 s. The TEM images demonstrate the formation of hexagonal and half-hexagonal forms with varying orientations, as well as the emergence of elongated tetragonal shapes, upon increasing the temperature to 900 °C. the notable enhancement in light absorption, with the absorption bands spanning a wide range in the UV–vis spectra, specifically from approximately 300 nm to around 800 nm in the near-infrared (NIR) region. The broad range of PL emission bands identified by this mixture of nanoparticles, expanding from the UV to the near and intermediate IR regions, demonstrated that NO/TO nanocpomposites are considerably defective. The NO/TO nanocomposites exhibit efficient multi-color band emissions at ambient conditions, rendering them promising contenders for deployment in optoelectronic nanodevices, including blue, yellow, and white band emission light-emitting diodes and NIR luminescence bioimaging.

Sustainable strategies for recovering metallic copper from waste printed circuit boards: Clean leaching and micro-nano copper powder preparation

Recovery and utilization of valuable metals from waste printed circuit boards (WPCBs) have the dual significance of alleviating resource shortages and protecting the ecological environment. This study focuses on the feasibility analysis of copper in WPCBs for preparing micro-nano copper powders by clean leaching and chemical reduction processes. Firstly, the effect of temperature and other parameters on copper leaching rate in glycine-hydrogen peroxide (Gly-H2O2), ammonia-ammonium chloride (NH3·H2O-NH4Cl) leaching systems with sulfuric acid-hydrogen peroxide (H2SO4-H2O2) system as control group were emphasized. Subsequently, the leaching characteristics of copper concentrate particles were analyzed by leaching kinetics to elucidate the leaching mechanism and apparent activation energy of copper. Finally, the micro-nano copper powders were prepared using ascorbic acid and sodium borohydride reduction system with different copper leach solutions as precursors. The micro-nano copper morphology and phase compositions were analyzed by SEM and XRD. The results show that both the Gly-H2O2 and NH3·H2O-NH4Cl system can replace the H2SO4-H2O2 system to achieve efficient leaching of copper. Increasing temperature can significantly enhance the copper leaching rate. When the temperature was increased from 15 °C to 45 °C, the maximum copper leaching rate in the three systems increased from 58.13 %,71.26 %,78.26 % to 90.36 %,91.21 %,92.87 %, at − 0.074 mm for 40 min. The Avrami model accurately describes the leaching behavior of copper concentrate particles, and the copper leaching process is dominated by chemical reaction control. SEM and XRD results show that micro-nano copper particles of hundreds of nanometers are successfully prepared by both reduction systems.

Molecular dynamics analysis of the effect of temperature on the internal structure transformation of polycrystalline 3 C-SiC nanoindentation

To investigate the structure changes of polycrystalline 3 C-SiC nanoindentation process and the influence of temperature effect on its changes, the nanoindentation experiments of polycrystalline 3 C-SiC are constructed by molecular dynamics method. The initial nanoindentation model of polycrystalline 3 C-SiC and diamond indenter is constructed based on the characteristics of Voronoi method in constructing close-packed spatial lattice. The temperature conditions of 300 K, 500 K, 800 K and 1000 K are selected to analyze the dislocation structure, number and length, internal atomic structure, grain boundary structure and deformation degree of polycrystalline 3 C-SiC during nano-indentation process. The stress and deformation of diamond indenter are analyzed. The results show that the higher the temperature, the higher the degree of dislocation stacking. Temperature has an effect on the internal variation of polycrystalline silicon carbide, particularly on the transverse size of the structure. The central force of the diamond becomes weaker and the force on either side becomes stronger. The temperature effect can change the stacking degree of dislocations, reduce the internal structure transformation rate of polycrystalline 3 C-SiC, and transform fewer discrete atoms and increase the number of cubic lattice atoms.

Effects of canopy gaps on microclimate, soil biological activity and their relationship in a European mixed floodplain forest

Forest canopy gaps can influence understorey microclimate and ecosystem functions such as decomposition. Gaps can arise from silviculture or tree mortality, increasingly influenced by climate change. However, to what degree canopy gaps affect the buffered microclimate in the understorey under macroclimatic changes is unclear. We, therefore, investigated the effect of forest gaps differing in structure and size (25 gaps: single tree gaps up to 0.67 ha cuttings) on microclimate and soil biological activity compared to closed forest in a European mixed floodplain forest. During the investigation period in the drought year 2022 between May and October, mean soil moisture and temperature as well as soil and air temperature fluctuations increased with increasing openness. In summer, the highest difference of monthly means between cuttings and closed forest in the topsoil was 3.98 ± 9.43 % volumetric moisture and 2.05 ± 0.89 °C temperature, and in the air at 30 cm height 0.61 ± 0.35 °C temperature. For buffering, both the over- and understorey tree layers appeared as relevant with a particularly strong influence of understorey density on soil temperature. Three experiments, investigating soil biological activity by quantifying decomposition rates of tea and wooden spatulas as well as mesofauna feeding activity with bait-lamina stripes, revealed no significant differences between gaps and closed forest. However, we found a positive significant effect of mean soil temperature on feeding activity throughout the season. Although soil moisture decreased during this period, it showed no counteracting effect on feeding activity. Generally, very few significant relationships were observed between microclimate and soil biological activity in single experiments. Despite the dry growing season, decomposition rates remained high, suggesting temperature had a stronger influence than soil moisture. We conclude that the microclimatic differences within the gap gradient of our experiment were not strong enough to affect soil biological activity considerably.

Bulge-Free and Homogeneous Metal Line Jet Printing with StarJet Technology.

The technology to jet print metal lines with precise shape fidelity on diverse substrates is gaining higher interest across multiple research fields. It finds applications in additively manufactured flexible electronics, environmentally friendly and sustainable electronics, sensor devices for medical applications, and fabricating electrodes for solar cells. This paper provides an experimental investigation to deepen insights into the non-contact printing of solder lines using StarJet technology, eliminating the need for surface activation, substrate heating, curing, or post-processing. Moreover, it employs bulk metal instead of conventional inks or pastes, leading to cost-effective production and enhanced conductivity. The effect of molten metal temperature, substrate temperature, standoff distance, and printing velocity was investigated on polymer foils (i.e., PET sheets). Robust printing parameters were derived to print uniform, bulge-free, bulk metal lines suitable for additive manufacturing applications. The applicability of the derived parameters was extended to 3D-printed PLA, TPU, PA-GF, and PETG substrates having a much higher surface roughness. Additionally, a high aspect ratio of approx. 16:1 wall structure has been demonstrated by printing multiple metal lines on top of each other. While challenges persist, this study contributes to advancing additively manufactured electronic devices, highlighting the capabilities of StarJet metal jet-printing technology.

The Effects of Upper-Ocean Sea Temperatures and Salinity on the Intensity Change of Tropical Cyclones over the Western North Pacific and the South China Sea: An Observational Study

With increasing air and sea temperatures, the thermodynamic environments over the oceans are becoming more favourable for the development of intense tropical cyclones (TCs) with rapid intensification (RI). The South China coastal region consists of highly densely populated cities, especially over the Pearl River Delta (PRD) region. Intense TCs maintaining their strength or the RI of TCs close to the coastal region can present substantial forecasting challenges and have significant potential impacts on the coastal population. This study investigates the effect of sea-surface and sub-surface temperatures and salinity on the intensification of five TCs, namely Super Typhoon Hato in 2017, Super Typhoon Mangkhut in 2018, and Typhoon Talim, Super Typhoon Saola, and Severe Typhoon Koinu in 2023, which have significantly affected the South China coastal region and triggered high TC warning signals in Hong Kong in the past few years. This analysis utilised the Hong Kong Observatory’s TC best-track and intensity data, along with sea temperature and salinity profiles generated using the China Ocean ReAnalysis version 2 (CORA2) product from the National Marine Data and Information Service of China. It was found that high sea-surface temperatures (SST) of 30 °C or above for a depth of about 20 m, low sea-surface salinity (SSS) levels of 33.8 psu or below for a depth of at least 20 m, and strong salinity stratification of at least 0.6 psu per 100 m depth might offer useful hints for predicting the RI of TCs over the western North Pacific and the South China Sea (SCS) in operational forecasting, while noting other contributing environmental factors and synoptic flow patterns conducive to RI. This study represents the first documentation of sub-surface salinity’s impact on some intense TCs traversing the SCS during 2017–2023 based on an observational study. Our aim is to supplement operational techniques for forecasting RI with some quantitative guidance based on upper-level ocean observations of temperatures and salinity, on top of well-known but more rapidly changing dynamical factors like low-level convergence, weak vertical wind shear, and upper-level divergent outflow, as forecasted with numerical weather prediction models. This study will also encourage further research to refine the analysis of quantitative contributions from different RI factors and the identification of essential features for developing AI models as one way to improve the forecasting of TC RI before the TC makes landfall near the PRD, with due consideration given to the effect of freshwater river discharge from the Pearl River.

Coupling field optimization to improve the thermal transport of Gr/h-BN heterostructure

We perform a numerical evaluation on the multi-physical field coupling effect to improve the interfacial thermal conductivity (ITC) of Gr/h-BN (Graphene/Hexagonal boron nitride) planar heterostructure. The model of Gr/h-BN planar heterostructure (C-BN bonded configuration) is built to investigate the effect of the multifactor coupling effect of different temperatures, N-doping concentration, and single vacancy concentration on the ITC. Finally, the Box-Behnken orthogonal model is established to determine the optimal value of ITC under the coupling effect of multi-physical fields by response surface analysis, and the optimal value of ITC is 14.456 GW m−2 K−1 when the temperature is 673 K, the single vacancy is 2.57 %, and the N-doping is 18.9 %. It implies that the proper coupling configuration is found effective in improving the interfacial thermal conductivity of the Gr/h-BN heterostructure. This work is hoped to help promote the thermal reliability design of graphene heterogeneous interface for related micro/nano semiconductor devices.

Ni-W composite coating reinforced with CrN nanoparticles on X80 pipeline steel: Preparation and characterization

X80 pipeline steel is crucial for oil and gas pipelines. Friction between particulate matter and the inner wall causes abrasive wear during transport, while corrosive environments further degrade the pipeline, leading to leaks. In this study, a nanoscale Ni-W-CrN composite coating was successfully prepared on X80 steel via electrodeposition for protection. The coating's surface morphology, microstructure, and composition were analyzed. The effects of CrN nanoparticle concentration and deposition temperature on the coating's structure, wear, and corrosion resistance were investigated. At 10 g/L CrN and 60°C, the Ni-W-CrN film showed a fine-grained surface with 8.13 wt% CrN, achieving 810 HV microhardness and improving wear and corrosion resistance by 81 % and 89 % compared to Ni-W coatings.

Ultrasonic Assisted Synthesis of 1,5-Bis(3'-ethoxy-4'-hydroxyphenyl)-1,4-pentadiene-3-one: Effect of Time and Temperature

Ultrasonic Assisted Synthesis of 1,5-Bis(3'-ethoxy-4'-hydroxyphenyl)-1,4-pentadiene-3-one: Effect of Time and Temperature

Microstructural analysis of cold-drawn medium-carbon low-alloy martensite: effect of deformation and tempering temperature

Microstructural analysis of cold-drawn medium-carbon low-alloy martensite: effect of deformation and tempering temperature

Praseodymium orthovanadate-waste PET bottle derived sulfur doped carbon for efficient Z-scheme photocatalytic CO2 reduction

Escalating amounts of carbon dioxide (CO2) in the Earth's atmosphere are a major cause of climate change and its negative consequences, making it a global concern. The present work highlights the intersection of waste management, resource utilization, and climate change mitigation, showcasing the potential for an additional sustainable and circular economy. Synthesizing carbon from waste polyethylene terephthalate (PET) bottles is an eco-friendly approach. X-ray diffraction, Raman spectroscopic, scanning electron microscopic, tunnelling electron microscopic, infrared fourier transform spectroscopy (FTIR) and X-ray photoelectron spectroscopic results indicate the effective extraction of carbon doped with sulfur (S@C) and the successive formation of nanocomposite with PrVO4 (PrV/S@C). Superior photocatalytic activity was observed under visible light compared to UV light. PrV/S@C showed enhanced light-driven CO2 reduction compared to pristine materials and was found to evolve 39, 56, and 98 µmol h−1 g−1 of H2, CH4 and CO, respectively. The effect of reaction temperature was examined and optimized at 100 °C. The enhanced activity in PrV/S@C compared to PrV and S@C probably due to the increased surface area, conductivity and synergy. In-Situ Diffused reflectance (DRIFT-IR) and liquid chromatography mass spectroscopy (LC-MS) confirm the evolution of CO and CH4. The optical, photo/electrochemical, Scavenger studies, Electron spin resonance (ESR) and Mott-Schottky studies suggest the formation of a direct Z-scheme photoredox reaction in the presence of PrV/S@C and sacrificial gent. The reusability studies for 5 cycles indicate good stability with a slight deviation in structure and morphology of PrV/S@C, as observed in XRD and SEM. Tackling plastic pollution and generating value-added carbonaceous products through CO2 reduction is the twin application of the present work that has piqued the interest of several researchers in environmental remediation.

Effect of irrigation solution temperature on complications of percutaneous nephrolithotomy: a systematic review of the literature, meta-analysis and trial sequential analysis of randomized clinical trials.

The optimal temperature of irrigation solution in patients undergoing PCNL is still unclear. Accordingly, this study aims to investigate the effects of different irrigation solution temperatures (cold/room temperature irrigation fluid versus warm/body temperature fluid). Our primary endpoint was hypothermia rate. Secondary outcomes were shivering rate, mean temperature decrease, mean patient final temperature, blood loss, and operative time. This systematic review was conducted in accordance with PRISMA guidelines. Multiple databases were searched in November 2023. Among 299 studies screened, eight were selected for full-text review, resulting in four randomized clinical trials that fit inclusion criteria and desired outcomes. Studies selection and data extraction were performed by multiple reviewers and a random-effects model was used for pooling of data. The primary outcome, hypothermia rate, showed a significant statistical difference between groups, occurring less frequently in the experimental group (35-37 ºC) than in the cold/room temperature irrigation group (RR 0.64;95%CI 0.46, 0.89; P<0.008; I2=33%). Secondary outcomes such as shivering rate (RR 0.46; 95%CI 0.31, 0.67; P<0.0001; I2=0%) and mean final temperatures (MD 0.43; 95%CI 0.12, 0.75; I2=82%) also showed statistically significant differences between groups, favoring the irrigation with heated fluid. There was a decreased rate of hypothermia and shivering among patients undergoing PCNL with warm irrigation fluid. Mean final temperatures were also higher in the experimental group. As to blood loss, mean hemoglobin decrease showed no statistically significant difference between groups, prompting further investigation of the influence of Irrigation solution temperature on blood loss volume.

A mean flow velocity estimation scheme based on flow field characteristics and distribution point optimization for carbon monitoring in coal-fired power plants: A numerical study

CO2 online monitoring provides a method to obtain carbon emissions by directly quantifying the flue gas flow rate and CO2 concentration. However, significant flow rate measurement errors arise due to the complexity of turbulence in large-diameter stacks. To address the issue, this study utilizes turbulence numerical simulation combined with mean velocity estimation error analysis to investigate the flow field of typical stacks in coal-fired power plants. The simulation results demonstrated that the evolution of turbulence exaggerates velocities. The flow field exhibits stable turbulence characteristics in a single-introduced stack, while in the double-introduced stack, the flow field dynamically evolves due to asymmetric collisions and abrupt expansions. Furthermore, the effects of load and temperature on the estimation error of flow velocity are established. The optimum monitoring height, the ideal chord angle and the stepped number of deployment points based on the log-linear method are determined. Within the single-introduced stack, a correction factor is introduced and a corresponding formula is established that links estimation errors with monitoring heights. This resulted in a dramatic reduction of the maximum estimation error from 14% to 0.3%. Finally, the systematic and simplified optimization scheme for estimating mean flow velocity is summarised, which provides a powerful reference for flow rate measurement for online CO2 monitoring in coal-fired power plants.