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The effect of Fe in the rapid thermal explosion synthesis and the high-temperature corrosion behavior of porous Co-Al-Fe intermetallic
No full textHigh porosity Co-Al-Fe intermetallic with 3D-microstructures were one-step synthesized via a novel thermal explosion reaction. A link between pore structure and permeability was established using 3D-XRM technology. The corrosion resistance of the samples with different Fe contents was investigated at 900 °C under an oxygen/sulphur atmosphere for up to 120 h. The results showed that the pore structure of the samples remains stable, and the internal matrices are intact due to the formation of a thin protective layer of Al2O3 and Fe2O3 on the surface of the product skeleton. In addition, inward diffusion of S leads to the formation of FeS nodules
Australia's geothermal frontier: Unlocking Granite's energy secrets
No full textComprehending the temperature-dependent mechanical behaviour of reservoir rocks under cyclic heating and cooling conditions holds significant implications for various deep-earth engineering applications, namely deep geothermal energy recovery, deep nuclear waste disposal, and coal gasification. In this study, the thermo-mechanical behaviour of Australian Harcourt granite is examined through a cyclic heating and quenching process. A series of comprehensive experiments were conducted to analyse the stiffness of the material, across a range of temperatures (20 °C–900 °C) and quenching cycles (1–15 cycles). The fracture distribution resulting from quenching cycles was investigated using Micro-CT scanning, while acoustic emission technology was employed to examine the fracture development, propagation, and failure process during shearing. The findings revealed that as temperature and heating/cooling cycles increased, the compressive strength, Young's modulus, shear modulus, crack damage threshold, and brittleness index exhibited a reduction. Conversely, the strain at failure and Poisson's ratio showed an increase. The cyclic quenching treatment resulted in significant rock degradation, as observed through increased porosity and cumulative acoustic emission counts with higher temperatures and heating/cooling cycles. These observations suggest that the granite transitions from a brittle to a “quasi-brittle” state as temperature and thermal cycles increase, signifying further evolution in its mechanical behaviour
Stages of readiness for advance care planning: Systematic review and meta-analysis of prevalence rates and associated factors
No full textBackground: Advance care planning has been widely recommended to respect the medical care preferences of patients in the final stages of life. However, uptake of advance care planning in healthcare settings remains suboptimal. It may be beneficial to take into account individuals' readiness for advance care planning based on the stages to change identified in the Transtheoretical Model. Objective: To identify the measurements used to assess readiness of advance care planning based on the Transtheoretical Model, to pool the prevalence of readiness stages, and to summarize the factors affecting people's readiness for advance care planning. Design: Systematic review and meta-analysis. Methods: We systematically searched the databases of PubMed, EMBASE, The Cochrane Library, CINAHL, and Web of Science for relevant studies from inception to February 2023. A random effects model was used to estimate the pooled prevalence. And a narrative review on the factors associated with stages of readiness was conducted. Results: This meta-analysis included 25 studies involving a total of 4237 individuals. The precontemplation stage was the most commonly identified stage of readiness among advance care planning behaviors (26–72 %). The prevalence of readiness stages for advance care planning varied among different types of behavior. The behavior of “talking to health care proxy/family/loved ones about thoughts on quality versus quantity of life” had the highest level of readiness among all listed behaviors, followed by “talking to health care proxy/family/loved ones about living will”, “signing a health care proxy form” and “signing a living will”, “signing an advance directive”, as well as “talking to doctors about living will”. Regarding to influencing factors, a majority of sociodemographic and clinical factors did not show consistent associations with readiness, but some studies did suggest potential links with age, health status, countries, type of assessment, core structures of the Transtheoretical Model, and intervention modalities. Conclusions: A majority of individuals were unaware of advance care planning. There is an urgent need to promote readiness for such planning. Starting with preliminary activities such as “talking to health care proxy/family/loved ones about thoughts on quality versus quantity of life” can help initiate advance care planning. Better integration of the Transtheoretical Model and interventions into the research of advance care planning readiness are needed. Registration: Not registered
Transforming nursing assessment in acute hospitals: A cluster randomised controlled trial of an evidence-based nursing core assessment (the ENCORE trial)
No full textBackground: Patient safety is threatened when early signs of clinical deterioration are missed or not acted upon. This research began as a clinical–academic partnership established around a shared concern of nursing physical assessment practices on general wards and delayed recognition of clinical deterioration. The outcome was the development of a complex intervention facilitated at the ward level for proactive nursing surveillance. Methods: The evidence-based nursing core assessment (ENCORE) trial was a pragmatic cluster-randomised controlled trial. We hypothesised that ward intervention would reduce the incidence of patient rescue events (medical emergency team activations) and serious adverse events. We randomised 29 general wards in a 1:2 allocation, across 5 Australian hospitals to intervention (n = 10) and usual care wards (n = 19). Skilled facilitation over 12 months enabled practitioner-led, ward-level practice change for proactive nursing surveillance. The primary outcome was the rate of medical emergency team activations and secondary outcomes were unplanned intensive care unit admissions, on-ward resuscitations, and unexpected deaths. Outcomes were prospectively collected for 6 months following the initial 6 months of implementation. Analysis was at the patient level using generalised linear mixed models to account for clustering by ward. Results: We analysed 29,385 patient admissions to intervention (n = 11,792) and control (n = 17,593) wards. Adjusted models for overall effects suggested the intervention increased the rate of medical emergency team activations (adjusted incidence rate ratio 1.314; 95 % confidence interval 0.975, 1.773), although the confidence interval was compatible with a marginal decrease to a substantial increase in rate. Confidence intervals for secondary outcomes included a range of plausible effects from benefit to harm. However, considerable heterogeneity was observed in intervention effects by patient comorbidity. Among patients with few comorbid conditions in the intervention arm there was a lower medical emergency team activation rate and decreased odds of unexpected death. Among patients with multimorbidity in the intervention arm there were higher rates of medical emergency team activation and intensive care unit admissions. Conclusion: Trial outcomes have refined our assumptions about the impact of the ENCORE intervention. The intervention appears to have protective effects for patients with low complexity where frontline teams can respond locally. It also appears to have redistributed medical emergency team activations and unplanned intensive care unit admissions, mobilising higher rates of rescue for patients with multimorbidity. Trial registration number: ACTRN12618001903279 (Date of registration: 22/11/2018; First participant recruited: 01/02/2019)
Exploiting domain knowledge to reduce data requirements for battery health monitoring
No full textRechargeable batteries are becoming increasingly significant in decarbonising the world. For their widespread usage, to monitor and predict the battery health status has been essential. Although machine learning has the potential to tackle this issue, considerable degradation tests are required for model training, leading to prohibitive costs and labour. Here, we introduce a novel approach to constructing health monitoring models by fusing battery degradation knowledge with deep learning, using a substantially reduced amount of degradation data. We employ a lightweight and interpretable model to produce synthetic charging curves from highly limited realistic data. Subsequently, a transfer learning technique is implemented to train a convolutional neural network using both types of data and alleviate their gap. By employing only 8 realistic charging curves to develop the model, the method can precisely estimate the maximum and remaining capacities from 300 mV charging segments. The root mean square errors for these estimations are below 12.42 mAh. Additional 50 validation cases confirm that the proposed method can not only reduce the required degradation data but also shorten the input window length. Furthermore, it can be generalised and applied to different battery types under different operating conditions. This work highlights the promise of employing domain expertise to significantly decrease the amount of battery testing required for monitoring battery health
Educational content and strategies to support nurses from culturally and linguistically diverse backgrounds caring for patients considering voluntary assisted dying: The Australian experience
No full textObjectives: Drawing on findings from a qualitative study that aimed to explore the knowledge and attitudes of nurses from culturally and linguistically diverse (CALD) backgrounds about voluntary assisted dying (VAD). The study also aimed to identify the strategies that assist nurses in their readiness and preparation for exposure to VAD. This paper reports on the educational content and strategies that could assist nurses from CALD backgrounds to be better prepared when they encounter VAD requests. Background: Around the world, healthcare professionals have roles to play in caring for patients requesting voluntary assisted dying. Nurses, particularly those from diverse geographic and clinical settings, have voiced inadequate knowledge and understanding about voluntary assisted dying. Design: A qualitative descriptive approach was undertaken. Methods: Data collection involved one focus group and 16 in-depth interviews. A total of 21 nurses from CALD backgrounds were recruited from one Australian state. Thematic analysis was conducted to interpret the data. Findings: Nurses identified their knowledge gaps and specified the need for education and workplace training on VAD, its legal and ethical aspects, clarity on their role, communication techniques and how VAD intersects with their practice. They suggested various teaching strategies that could prepare nurses to work safely and confidently in a clinical environment where voluntary assisted dying is an option for patients. Conclusion: Given the high number of nurses from diverse backgrounds working in the Australian health sector, these nurses need to be fully prepared to care for patients requesting VAD
Semi-active inerters: a review of the literature
No full textThe inerter was introduced as a mechanical counterpart to the electrical capacitor, completing the force-current analogy. This is a one-port, two-terminal device in which the equal and opposite forces exerted at its terminals are proportional to the relative acceleration between them. Within this relationship, the “inertance” is the coefficient of proportionality and carries the unit of mass. This implies that the inerter can exert an inertial force at its terminals, effectively representing a virtual mass. Due to these properties, inerters have gained popularity, finding applications as components of vibration control systems and energy harvesters. Derived from passive inerters, semi-active inerters are integrated with active control systems to regulate their inertance. Since their introduction, semi-active inerters have been pivotal in situations demanding active monitoring of natural frequency or control force, generally outperforming their passive counterparts. While numerous significant reviews on passive inerters and their applications have been published in respected journals, dedicated literature reviews on semi-active inerters remain scarce. This review seeks to bridge this gap, offering a comprehensive literature review on semi-active inerters and highlighting research challenges and opportunities. Given the novelty of semi-active inerters, they present a fascinating area of study
Modelling the flux decline induced by gypsum scaling in direct contact membrane distillation
No full textScaling has been a major technical challenge in the membrane distillation (MD) process, hindering the broader application of MD processes. Despite the increasing number of studies on MD scaling, there are limited prediction tools to describe the scaling process and help make informed decisions about the experimental conditions to prevent scaling and its irreversible damage. In this paper, a semi-analytical model was developed based on the classical nucleation theory and crystal growth to model the membrane area reduction caused by the deposition of inorganic salt crystals on the membrane surface, which is equivalent to the decrease in permeate flux resulting from scaling. The model was developed using calcium sulphate, a model scalant. The model was validated and verified with available literature data, and it has been proved that the model has the capability to produce reasonable predictions on the onset of flux decline and the declining rate with respect to the experimental data with the coefficient of determination (R2) ranging from 0.74 to 0.96. The sensitivity analysis was applied on the model, which revealed that flux decline would happen earlier in the case of higher feed temperature, higher feed velocity, and higher initial feed concentration
Te-vacancy-rich CoTe2−x anodes for efficient potassium-ion storage
No full textMetal tellurides (MTes) have emerged as highly promising anode materials for potassium-ion batteries (PIBs) due to their exceptional volumetric capacity and superior electronic conductivity. The practical application of MTes, however, faces challenges such as slow kinetics, volumetric effects, and ill-defined shuttling phenomena of K-polytellurides (K-pTex). Herein, we present a groundbreaking solution through the development of Te-vacancy-rich CoTe2−x nanoparticles confined within a 3D honeycomb-like, hollow hierarchical gridded porous structured, S, N co-doped dual-carbon structural composite (CoTe2−x@3DPSNDC) via facile defect chemistry. This well-designed composite offers an unparalleled combination of fast ion/electron transport and stable K-pTex, propelling battery reactions to new heights. State-of-the-art in-/ex-situ techniques and density functional theory calculations reveal the evolution and shuttling mechanism of K-pTex. Remarkably, our study validates the exceptional physical confinement and chemisorption capabilities of S, N co-doped dual-type carbon skeletons on K5Te3 and K2Te3, leading to ultra-stable potassium-ion storage. Furthermore, the Te vacancies substantially boost the intrinsic conductivity of CoTe2−x, resulting in accelerated reaction kinetics and enhanced rate performance of the CoTe2−x@3DPSNDC electrode which achieved an impressive capacity of 508.1 mAh cm−3 at 5.0 A g−1. Our advanced design concept provides unique insights into the construction of MTes anodes for achieving stable cyclability and fast-charging PIBs
Influence of GNPs solid lubricant on the fabrication of Cu/SS304L composite micro channels
No full textThe different solution-processed concentrations of graphene solid lubricant (0 – 30 mg/mL) were applied on the surface of copper/stainless steel 304 L composite foils. A variable trend of rolling force occurs, with a first falling and then rising trend and the lowest rolling force was obtained at 25 mg/mL for 3.82 kN. Besides, the height of ridges and aspect ratio were improved with an increased solution-processed concentration. On the valley surfaces, the GNPs filled up the cracks, flattened the grooves and eliminated the micro scratches. This indicates the self-repairing and self-polishing mechanisms of GNPs in the micro rolling process. The sliding and exfoliation of GNPs also contributed to the reduced roughness and improved quality of the sample surfaces