bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and Operability Challenges for Supercritical CO2 Plants: The sCO2-Flex Centrifugal Compressor Test Experience
Authors: Manuele Bigi , Valentina Bisio , Silvia Evangelisti , Marco Giancotti , Alberto Milani , Tiziano Pellegrini 
Published: September 2022

Abstract
Interest in supercritical carbon dioxide (sCO2) cycles has grown significantly in recent years. The peculiar properties of the fluid open unique opportunities but also poses several challenges. This article aims at narrowing the knowledge gap in operating such plants, leveraging the test experience of a full-scale 5 MW centrifugal compressor (CC) prototype designed for the sCO2-flex project (H2020 funded program, grant agreement No. 764690). The test rig replicated a complete recycle loop for the compressor. In addition to validating the compressor's performances in its design condition, a larger envelope of operation and transients was explored. The chapter describes engineering groundwork and design choices regarding: (i) transient operation such as pressurized startups and emergency shutdowns (ESDs); (ii) safety relief valves and discharge lines, with possible CO2 solidification; and (iii) vibrations due to extremely high density. For all these topics, specific challenges brought by the sCO2 are described. The most meaningful results, in excellent agreement with predictions, are shown; key learnings from the test experience are discussed. The importance of anticipating risks during the design phase is highlighted and recommendations for similar installations are given. The article concludes with hints on testing severe off-design conditions, with two-phase flow at compressor suction.
Experimental Ignition Delay Time Measurements and Chemical Kinetics Modeling of Hydrogen/Ammonia/Natural Gas Fuels
Authors: Baker Jessica B. , Rahman Ramees K. , Pierro Michael , Higgs Jacklyn , Urso Justin , Kinney Cory , Vasu Subith 
Published: September 2022

Abstract
In recent years, hydrogen-carrying compounds have accrued interest as an alternative to traditional fossil fuels due to their function as zero-emission fuels. As such, there is interest in investigating hydrogen-carrying compounds to improve understanding of the fuels' characteristics for use in high pressure systems. In the current study, the oxidation of ammonia/natural gas/hydrogen mixtures was carried out to study carbon monoxide (CO) formation profiles as well as the ignition delay times (IDTs) behind reflected shock waves in order to refine chemical kinetic models. Experiments were carried out in the University of Central Florida's shock tube facility by utilizing chemiluminescence to obtain OH* emission and laser absorption spectroscopy to obtain CO profiles over a temperature range between 1200 K and 1800 K with an average pressure of 2.2 atm. Experimental mixtures included both neat and combination natural gas/hydrogen with ammonia addition, with all mixtures except one having an equivalence ratio of 1. Results were then compared with the GRI 3.0 mechanism, as well as the newly developed UCF 2022 mechanism utilizing chemkin-pro software. In general, both models were able to capture the trend in auto-ignition delay times and CO time histories for natural gas and ammonia mixtures. However, for ammonia–hydrogen mixtures, GRI 3.0 failed to predict ignition delay times, whereas the UCF 2022 mechanism was able to capture the IDTs within the uncertainty limits of the experiments. A sensitivity analysis was conducted for different mixtures to understand the important reactions at the experimental conditions. Finally, a reaction pathway analysis was carried out to understand important ammonia decomposition pathways in the presence of hydrogen and natural gas.
Sustainability Improvement of Membrane Separation Process for Post-Combustion CO2 Capturing Using Multi-Objective Optimization
Authors: Asadi Javad , Kazempoor Pejman 
Published: September 2022

Abstract
The membrane process is a promising technology for CO2 removal and mitigation. Since the energy consumption and economy of membrane-based carbon capture systems (CCSs) are critical for their large-scale deployments, optimal design and operation of such systems are the primary aims of this study. To achieve these research goals, a numerical model based on the solution-diffusion mechanism for the multicomponent gas separation process with a hollow-fiber membrane module is developed using Aspen Custom Modeler. The model is employed to investigate the effects of important operating and design parameters. Multi-objective process optimization is then performed by linking Aspen Plus and MATLAB and using an evolutionary technique to determine the optimal operating and design conditions. Our results show that by increasing the CO2 concentration in the feed gas, the CO2 capture cost significantly decreases and CO2 removal improves, although the process energy requirement slightly increases. The best achievable tradeoffs between objective functions are generated and analyzed, which substantiate the significant potential for improving the sustainability of the process. The results show that at optimum design and operating conditions, CO2 capture cost and energy consumption of the process could be as low as 13.1 $/tCO2 and 61 MW, respectively. The results of this study provide valuable insights into membrane separation and can be used by decision-makers to achieve the optimal performance of the process for commercial development and deployment of the technology.
Efficiency and Flexibility Improvement of Amine-Based Post Combustion CO2 Capturing System (CCS) in Full and Partial Loads
Authors: Asadi Javad , Jolaoso Lateef , Kazempoor Pejman 
Published: September 2022

Abstract
Optimal design and operation of the CO2 captures system integrated with power plants are crucial to minimize process energy consumption and associated costs. In this paper, the conventional process of monoethanolamine (MEA)-based post-combustion CO2 capturing system is modified to reduce the process energy consumption for flexible and efficient integration to fossil-fueled power plants. Considering a flue gas stream similar to coal-fired power plants, rigorous rate-based modeling of the MEA-based CO2 capture system is performed in Aspen Plus using the electrolyte nonrandom two-liquid thermodynamic package (ENRTL-RK). Afterward, three main process modifications, including lean vapor compression, rich solvent preheating, and rich solvent splitting, are investigated in both full and partial load conditions to assess their impacts on the process efficiency and energy consumption. The results demonstrate that the lean vapor compression and the rich solvent preheating modifications significantly reduce the process energy consumption by 13.5% and 8.4%, respectively. However, the addition of extra equipment such as compressors, flash vessels, and heat exchangers increase the capital and operational costs of the capture plant. Also, rich solvent splitting, which requires minor modifications in process equipment, reduces the energy consumption by 5.4%. Moreover, it is observed that the operating conditions for CO2 capture vary significantly between partial and full load conditions, and considerable reduction in energy consumption and improvement in process flexibility can be achieved at optimal process conditions.
A Review of Passive Cooling Technology Performance Testing Methods
Authors: Young David A. , Stefanakos Elias , Goswami D. Yogi 
Published: September 2022

Abstract
Recent research has shown that it is possible to achieve significant cooling by radiative methods without the use of mechanical equipment that require significant amount of electrical power. These passive cooling methods rely on reflecting most of the solar radiation and emitting radiation in the “atmospheric window” wavelength ranges where the atmosphere is transparent, so that a surface exchanges radiation directly with the extremely cold outer space. This literature review noted that almost all published experimental studies on radiative cooling were conducted under different environmental conditions and methodologies, making it almost impossible to compare the results. In this paper, we present a literature review, focusing on daytime radiative cooling performance, that showed an array of testing methods and environmental conditions, leading to the research question of how these technologies would compare with the same testing standard. Slight variations in environmental conditions, setup, and instrumentation from one experiment to another can present large differences in reported performance, even for the same passive radiative cooling device. Examples of setups include non-standard insulated testing chambers, convection barriers, vacuum chambers, shading devices, and instruments like feedback heaters, pyranometers, infrared radiometers and thermocouples. The testing methods reviewed point to the need for a standard cooling potential performance measurement method for the advancement of passive radiative cooling technology.
Performance Measurement and Verification of Variable-Speed Packaged Rooftop Units
Authors: Wang Weimin , Katipamula Srinivas , Underhill Ronald 
Published: September 2022

Abstract
Packaged rooftop units (RTUs) are widely used in commercial buildings. Most RTUs in the field are equipped with constant-speed fans and compressors. Many efforts have been made to increase the operational efficiency of RTUs with advanced design and controls. This paper presents a field study that evaluates the cooling efficiency and energy performance of RTUs with all variable-speed components, including the supply fan, the compressor, and the condenser fan. The field evaluation was performed at two sites: a supermarket in New Smyrna Beach, FL and an office building in Fort Worth, TX. On each site, a conventional RTU with constant-speed fans and compressors was selected as the reference. A set of sensors were used to measure the dry-bulb temperature and the relative humidity for the outdoor air, the return air, the mixed air, and the supply air. The RTU total power consumption was also measured using a power transducer. These sensor measurements, together with a number of control signals were monitored at 1-minute intervals. Based on the monitored data, the energy efficiency ratios (EERs) was computed for each unit daily and over the entire monitoring period. On the Florida site, the advanced RTU had an overall EER of 10.9, which was about 31% higher than the reference unit. In contrast, on the Texas site, the advanced RTU had an overall EER of 12.2, which was about 16% higher than the reference unit. The economic analysis showed that relative to an alternative scenario that either the units were not replaced or like-to-like replacements were made, the advanced RTU could at least reduce the electricity bill by $1670/yr and $4082/yr on the two sites.
Energy and Exergy Analysis of a Developed Compound Parabolic Collector Using a Pumped Solar Water Heating System
Authors: Kashamba Kabo , Letsholo Tlhalefo P. , Masoso Okatoseng T. , Nwaigwe Kevin N. 
Published: September 2022

Abstract
Solar water heating systems utilize different types of collectors in heating water. Therefore, a study on energy and exergy analysis of a compound parabolic collector in a pumped solar water heating system is presented. The compound parabolic collector was designed using basic sizing principles and constructed using locally available materials. The materials used in the construction include aluminum for the concentrator, copper pipes for the circulation of water through the system and mild steel for the compound parabolic collector frame. A detailed description of the construction steps followed in the development of the compound parabolic collector is presented. An experimental active solar water heating system consisting of the compound parabolic collector, a storage tank and a pump was used for analysis of energy and exergy. A pyranometer and probes were placed at the experimental site to measure solar radiance and ambient temperature respectively at the intervals of ten minutes. Experiments were carried out using the solar water heating system and a net temperature rise of 22.4°C was obtained. The energy efficiency of the compound collector was 93.1% while the obtained exergy efficiency was 20.1%. The results show that the developed compound parabolic collector is very effective in solar water heating and agrees with established research.
The Factor of Australia in British Foreign Policy
Authors: Godovanyuk K. A. 
Published: September 2022

Abstract
The Australian component of UK foreign policy in the context of the changing world order is outlined. It is highlighted that, in a value and ideological sense and due to the common Anglo-Saxon identity, London assigns Canberra a key role in the coalition of like-minded countries (“network of liberty”); in geostrategic terms, it perceives Australia as a platform to expand the UK influence in the Indo-Pacific. At present, the “special” partnership between the two countries is underpinned by a number of new agreements, including a “historical” trade deal aimed at strengthening economic ties and in-depth political, diplomatic, and defense cooperation, based on a new military alliance, AUKUS. At the same time, the traditional pragmatism inherent in the foreign policy of Australia, which positions itself as a reliable international actor, is being replaced by increasing military–political and economic dependence, which plays into the hands of London. Coming closer with Australia also allows Britain to present itself as the key extraregional player in the system of anti-Chinese alliances in the Indo-Pacific, with Washington and Canberra in the forefront.
European Culture: Centripetal and Centrifugal Forces
Authors: Gromyko Al. A. 
Published: September 2022

Abstract
The main features of the transformation of European culture in the modern world are explored. Chronologically, this study is based on the idea of the general humanistic foundations of European culture since the 1980s. The author describes its state during the Cold War, and then analyzes the search for its new meanings, including the concept of the “new Middle Ages” and the theme of fear. Another dimension of the research is the role of the Age of Enlightenment in the history of European culture and its later development in the context of liberalism, consumerism, and individualism. Contemporary European culture is characterized as an overlap of premodern, modern, and postmodern. The problem of Westernization and standardization of culture is dwelt upon together with the shift to different currents of postmaterialism and neo-avant-garde art.
The Influence of NATO Regional Missile Defense on European Security
Authors: Krivolapov O. O. 
Published: September 2022

Abstract
The problem of missile defense is considered by Russian researchers, first of all, as part of the strategic stability problem in relations between Russia and the United States. At the same time, the impact of regional missile defense (theater missile defense) on regional security remains largely unexplored. The US and NATO leadership continue to claim that Russia has deployed intermediate-range missiles in the European part of the country. As a response to this step, in addition to other measures of regional deterrence towards Russia, it is planned to strengthen NATO’s regional missile defense system. The purpose of this article is to determine the potential impact of enhancing NATO’s theater missile defense on regional security. The answer to this question is important for understanding the prospects for European security. This article provides a critical analysis of Western experts’ scenarios of actions of Russia and NATO around the Baltic countries the place and role of theater missile defense in these scenarios and compares the doctrinal guidelines of the United States and Russia regarding regional nonnuclear deterrence. There are situations in which NATO’s enhanced regional missile defense could strengthen regional deterrence, and there are situations where this is less likely. Taking into account the doctrinal guidelines of both sides, conclusions are drawn about the destabilizing potential of NATO’s regional missile defense enhancement and that, in strengthening regional stability, there is no alternative to arms control and transparency regimes.
Does persistent precarious employment affect health outcomes among working age adults? A systematic review and meta-analysis
Authors: Pulford Andrew , Thapa Alekh , Thomson Rachel M , Guilding Annette , Green Michael James , Leyland Alastair , Popham Frank , Katikireddi Srinivasa Vittal 
Published: September 2022

ObjectiveTo evaluate the impact of persistent precarious employment (lasting 12+ months) on the health of working age adults, compared with more stable employment. Persistent precarity reflects a shift towards less secure forms of employment and may be particularly important for health.MethodsNine databases were systematically searched to identify quantitative studies that assessed the relationship between persistent precarious employment and health outcomes. Risk of bias (RoB) was assessed using an adaptation of the Effective Public Health Practice Project tool. Narrative synthesis and random effects meta-analysis were conducted. Certainty of evidence was assessed using the Grades of Recommendations, Assessment, Development and Evaluation (GRADE) approach.ResultsOf 12 940 records screened, 50 studies met the inclusion criteria and 29 were included in meta-analyses. RoB was generally high (n=18). The most reported outcome domain was mental health; with evidence also reported relating to general health, physical health,and health behaviours. Of GRADE assessed outcomes, persistent precarious employment was associated with increased risk of poor self-rated health (OR 1.53, 95% CI 1.09 to 2.14, I2=80%) and mental health symptoms (OR 1.44, 95% CI 1.23 to 1.70, I2=65%). The association with all-cause mortality was imprecisely estimated (OR 1.10, 5% CI 0.91 to 1.33, I2=73%). There was very low GRADE certainty across all outcomes.ConclusionsPersistent precarious employment is associated with poorer health, particularly for outcomes with short time lags, though associations are small and causality is highly uncertain. Further research using more robust methods is needed but given potential health harms of persistent precarious employment, exploration of precautionary labour regulations and employment policies is warranted.
Identifying racial disparities in hereditary hemorrhagic telangiectasia
Authors: Yusuf Hamzah , Rasheed Amna , Kim Helen , Conrad Miles B , Hetts Steven W 
Published: September 2022

BackgroundHereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disorder characterized by recurrent epistaxis (nose bleeds), mucosal telangiectasias (spider veins), and arteriovenous malformations. Although HHT affects all racial groups, few studies have explored racial disparities among patients with HHT.MethodsWe performed a retrospective chart review of HHT patients who were seen at a single academic center between July 1, 2014 and January 1, 2022. The primary outcomes of this study were the Epistaxis Severity Score (ESS) and the presence of pulmonary, cerebral, gastrointestinal, spinal, and hepatic arteriovenous malformations (AVMs). We analyzed racial differences using t-tests and analysis of variance (ANOVA) for continuous variables, and chi-squared tests for categorical variables. We then performed multivariable linear and logistic regressions on outcomes.ResultsOur review identified 35 Asian, 6 Black or African American, 72 Hispanic or Latino, and 244 White or Caucasian patients who met the inclusion criteria. Through an analysis of variance model, race/ethnicity was not significantly associated with ESS. Two univariable logistic regression models between race and both pulmonary and brain AVMs showed that race was associated with the incidence of pulmonary AVMs (p<0.01), with Asian patients at a 2.3-fold increased risk of pulmonary AVMs compared with White patients (p=0.03). Race was also associated with the incidence of cerebral AVMs (p<0.01) with Hispanic or Latino patients at a 4.8-fold increased risk compared with White patients (p<0.01).ConclusionPatients who identified as Asian may have higher rates of pulmonary AVMs while patients identifying as Hispanic or Latino may have more cerebral AVMs. The correlations may be important for identifying risk factors in certain patient populations.
Aβ Protein Detector Based on AAO Confined Self-Assembly System
Authors: Xu Chao , Lu Mengyang , Xu Weiran , Xiong Xudong , Fan Zhao , Wang Yongqian 
Published: September 2022

With the advent of the aging of the world’s population, the number of patients suffering from Alzheimer’s disease (AD) is increasing year by year, and how to diagnose early and treat AD has become a problem for the world. After decades of hard work, people have made a series of breakthroughs in the pathogenesis of AD. One of the most widely accepted is that there is a large amount of amyloid-[Formula: see text] protein deposition in the body of AD patients. This also provides us with a new idea for early diagnosis of AD. In this paper, a confined self-assembly system based on AAO/ZnS is constructed to specifically respond to amyloid-[Formula: see text] protein. The obtained samples were characterized by FESEM, XPS and UV–Vis. This system specifically recognizes A[Formula: see text] protein by modifying the tryptophan enantiomers. The experimental results show that the samples synthesized under the self-assembly system of modified D-Trp have higher response sensitivity to amyloid-[Formula: see text] protein. This provides a new idea for the self-assembly system based on the limited space of the nano-biomimetic channel in biological detection, and also shows great potential in improving the sensitivity of the biodetector.
Examining the Culture of Excellence (CoE) within a Private Philippine Higher Education Institution amidst of the Global Health Crisis
Authors: Andaya Mitch , Buyco Hamil , Cabo Danica Chrizzy Ann , Dayrit Rheal , Duenas Jean , Espardinez Weena Jennifer , Ferraro John Bryan , Oriel Margery , San Pedro Jay R , Sucaldito Shania Jane , Tan Benjamin , Caballes Dennis 
Published: September 2022

Excellence is one of the thriving drives that any Higher Education Institution in Philippines to be attuned regardless of the challenges imposed by the society, especially during the initial phase of the global health crisis. The context of excellence in Higher Education has different vantage points that have great indicators or manifestations of being excellence in different foundational pillars of Higher Education Institutions. With this, the researchers examined the Culture of Excellence among the employees of a Private Philippine Higher Education Institution during the pandemic COVID-19 through a descriptive-correlational research design. Thus, the researchers developed and validated a research instrument that suited for the intention of the study. The developed research instrument was digitized and floated accordingly. Whereas, respondents were determined through the collaboration of the purposive and stratified sampling techniques. Afterward, the collected data was statistically analysed using frequency, percentage, weighted mean, standard deviation, and appropriate correlational analysis. It revealed that the respondents agree that they observed the indicators of Culture of Excellence despite of the global health crisis and modality of working. Furthermore, age and educational background were statistically related to their perception towards the Culture of Excellence. Based on these insights, the researchers created a proposed action plan to further harness and strengthen the said culture among the employees of the institution.