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Seismic hazard analysis and seismic fragility analysis are import parts of seismic risk analysis of the nuclear power plant, and the site-specific spectra generation and selection of ground motion records are the key connecting steps between seismic hazard analysis and seismic fragility analysis. The site-specific spectra based on scalar probabilistic seismic hazard analysis and seismic hazard disaggregation have been widely studied and used. In order to overcome some shortcomings of some site-specific spectra such as uniform hazard spectrum and conditional mean spectrum, the theory of generalized conditional mean spectrum with multiple conditional periods has been proposed. However, the generalized conditional spectra based on the characteristics of Chinese seismicity have not been studied as far as the author knows. Meanwhile, the safety factor method is a common method for seismic fragility analysis of the nuclear power plant. In recent years, the fragility analysis of the nuclear power plant based on analytical fragility data has been applied and studied. At present, the seismic fragility of the nuclear power plant has been usually analyzed based on one single ground motion intensity measure, which contains limited information, and the obtained fragility analysis results are uncertain. The research on multivariate fragility of the nuclear power plant based on analytical seismic fragility analysis methods such as incremental dynamic analysis is still lacking. In this paper, the multivariate seismic fragility analysis of a nuclear power plant containment in China was conducted via the generalized conditional spectrum for the nuclear power plant site in China. Firstly, based on the vector probabilistic seismic hazard analysis and disaggregation theory of the site in China, the generation method and steps of the generalized conditional spectra of the site in China were proposed. For the example site located in China, the generalized conditional spectra of the example site were generated. Based on the generated generalized conditional spectra of the example site, the ground motion records were selected via greedy optimization algorithm, and based on the multivariate seismic fragility analysis method, the multivariate seismic fragility surface of the containment structure of the example site were generated. The seismic fragility analysis results of the nuclear power plant containment are sensitive to multiple ground motion intensity measures. Based on analytical seismic fragility methods such as incremental dynamic analysis, more refined fragility analysis results can be obtained. Seismic fragility analysis results considering multiple ground motion intensity measures can provide research basis for more refined seismic risk of nuclear power plants.

This paper estimates a correlation model and joint distribution model of spectral accelerations of vertical ground motions based on the NGA-West2 ground motion database. The correlation model calculated via BC16 vertical GMPE in this study is compared with those published models via other vertical NGA-West2 GMPEs. It is verified that the calculated residuals of vertical ground motions at multiple periods follow the multivariate normal distributions via both a qualitative validation method and a set of quantitative validation methods. The correlation model and the joint distribution model of vertical spectral accelerations are the theoretical basis for research on the joint occurrence of spectral accelerations of vertical ground motions, and an example of applied research on joint occurrence of spectral accelerations of vertical ground motions is studied: the conditional mean spectrum of vertical ground motions. Finally, the effects of different vertical correlation models and ground motion prediction equations on vertical conditional spectra are investigated for wide application of the correlation model and the joint distribution model of spectral accelerations of vertical ground motions. [ABSTRACT FROM AUTHOR]

Solar energy, a pivotal renewable resource, faces operational challenges due to its intermittent and unstable power output. Thermal energy storage systems emerge as a promising solution, with phase change materials (PCMs) packed beds attracting attention for their compactness and stable temperature transitions. This paper details a laboratory-scale solar thermal storage PCM packed bed integrated with a heat pump, utilizing a novel form-stable PCM. A numerical model was established to assess the thermal storage characteristics and heat extraction performance of the solar PCM packed bed coupled with a heat pump. Simulation results show that increasing solar irradiance significantly reduces storage duration, achieving full thermal storage in 3.4 h at 900 W/m2 irradiance. Optimal starting times were identified as 9:00 a.m. or 11:00 a.m., with later starts resulting in incomplete storage due to the PCM not reaching its phase change temperature. Additionally, packed bed parameters influenced storage conditions; increasing the paraffin content in the PCM extended the phase change duration, while graphene nanoparticles slightly reduced it. Lower porosity (0.49) beds, with higher PCM content, reached 70 °C quicker than higher porosity (0.61) beds due to higher pressure drops promoting more uniform flow and temperature distribution. During heat extraction, coupling the heat pump at 2 liters/min achieved temperatures below 45 °C in 4.1 h, while at 6 liters/min, the time reduced to 1.6 h, demonstrating adaptability to different extraction rates. These findings provide insight into the thermal performance of solar PCM packed beds coupled with heat pumps, contributing to efficient and stable thermal utilization of solar energy. [ABSTRACT FROM AUTHOR]

Building production increases energy demand, which raises carbon dioxide emissions and leads to environmental degradation. The use of prefabricated buildings has the potential to play an important role in promoting sustainable development in the construction industry, and prefabricated building incentive policies (PBIP) are an effective means of improving the development level of prefabricated buildings (PBDL). This study investigated the significance of PBIP using a structural equation model (SEM) analysis of the results of 519 questionnaire surveys obtained in 10 prefabricated building demonstration cities in China. The results indicate that policy satisfaction has the most substantial impact on PBDL, with direct funding subsidy policy being the most influential factor. Policy application enthusiasm ranks second according to influence on PBDL, while policy awareness has the most negligible impact on PBDL among the examined factors. This research provides a reference for the government to formulate reasonable and effective prefabricated building incentive policies, and it may be useful for promoting the development of prefabricated buildings. [ABSTRACT FROM AUTHOR]

Introduction: Patients undergoing total aortic arch replacement (TAAR) usually require blood products perioperatively. This cohort study aimed to investigate the impact of a comprehensive blood conservation program on the major complications in these patients. Methods: Patients with traditional or comprehensive blood management intraoperatively from January 2017 to December 2018 were included. We compared the rates of major complications (cerebral vascular accident, acute kidney injury, or mortality) between the two groups after propensity score matching (PSM). The association between blood management and outcomes was assessed by logistic regression. Restricted cubic splines (RCS) were built to evaluate the impact of fresh frozen plasma (FFP) on complications. Patients were stratified by the ratio of FFP/RBC (red blood cell) to investigate the effect of the ratio on complications. Results: After 1:1 PSM, 200 patients were selected. 35% (35/100) of patients suffered major complications in the traditional group, while it decreased to 22% (22/100) in the comprehensive management group (OR = 0.524, p = 0.043). Multivariable logistic regression showed that FFP was a risk factor (OR = 1.186, p = 0.014). RCS results indicated that with the increase of FFP, the risk of complications gradually increases. The cut-off value was 402 mL. Patients in the group of ratio = 0 ∼ 0.5 had a higher chance than those without transfusion (OR = 7.487, p < 0.001). Conclusions: Comprehensive blood conservation program in patients undergoing TAAR is safe and can reduce the incidence of major complications, which are associated with FFP volume and the ratio of FFP/RBC. [ABSTRACT FROM AUTHOR]

This paper estimates the joint occurrence of spectral accelerations (SA) between horizontal (HGM) and vertical ground motions (VGM) based on the NGA-West2 ground motion database, which includes the correlation model and joint distribution model. In this study, the correlation model calculated via CB14 horizontal ground motion prediction equation (GMPE) and BC16 vertical GMPE is obtained. It is verified that the joint distribution of residuals follows a multivariate normal distribution via both a set of quantitative validation methods and a qualitative validation method. Conditional mean spectra of VGMs conditioned on SAs of HGMs are studied as an application of joint occurrence of SAV–SAH. [ABSTRACT FROM AUTHOR]

The solubility of stevioside (a natural sweetener) in 12 pure solvents (methanol, 1-propanol, 2-propanol, 1-buthanol, 2-buthanol, 1-pentanol, 2-pentanol, 2-ethoxyethanol, 2-propoxyethanol, 2-buthoxyethanol, water, and acetone) and in binary mixed solvents (2-ethoxyethanol + water) have been determined using high performance liquid chromatography (HPLC) method at temperatures ranging from 288.15 to 328.15 K and atmospheric pressure. From the experimental data, it was found that the solubility increased with the rising temperature in all selected solvents. The experimental data for the solubility of stevioside were correlated with Apelblat and non-random two-liquid (NRTL) models. It was found that the Apelblat model has the better quality in fitting the solubility data. Also, thermodynamic functions of dissolution, mixing and transfer process were calculated by the van't Hoff equation. Furthermore, the crystal habits of stevioside in selected solvents were studied. Key words: solubility, stevioside, Apelblat equation, NRTL model, thermodynamic properties. Nous avons determine la solubilite du stevioside (un edulcorant naturel) dans 12 solvants purs (methanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxyethanol, eau et acetone) et dans un melange binaire de solvants (2-ethoxyethanol + eau) au moyen de la chromatographie liquide a haute performance (HPLC) a des temperatures allant de 288,15 a 328,15 K sous pression atmospherique. A partir des donnees experimentales, nous avons observe que la solubilite augmentait en fonction de l'augmentation de la temperature dans tous les solvants selectionnes. Les donnees experimentales de la solubilite du stevioside etaient correlees selon les modeles d'Apelblat et NRTL (de l'anglais non random two liquids, deux liquides ordonnes). Nous avons observe que le modele d'Apelblat offrait un meilleur ajustement des donnees de solubilite. Par ailleurs, nous avons calcule les fonctions thermodynamiques des processus de dissolution, de melange et de transfert au moyen de l'equation de van't Hoff. Nous avons egalement etudie les formes cristallines du stevioside dans les solvants selectionnes. [Traduit par la Redaction] Mots-cles: solubilite, stevioside, equation d'Apelblat, modele NRTL, proprietes thermodynamiques., 1. Introduction The increasing consumption of sugars has resulted in several nutritional and medical problems such as obesity, diabetes, and cardiovascular diseases. Therefore, low calorie sweeteners have been investigated as [...]

In this study, 3 residential buildings with installed high-efficiency filter fresh air system, coarse-efficiency filter fresh air system and air purifier were selected respectively to analyze the purification effect of different air purification equipment on indoor pollutants in winter. Data on ventilation and concentrations of PM2.5 and CO2 were collected through long-term online monitoring. The test results showed that under the same outdoor pollution condition, the average indoor PM2.5 concentration of residential buildings equipped with high-efficiency filter fresh air system and air purifier was 33.62μg/m3 and 34.32μg/m3, respectively. However, the purification effect of coarse-efficiency filter fresh air system was poor, and the indoor PM2.5 concentration over-standard rate reached 13.11%. It was a slow process for the fresh air system to reduce indoor CO2 concentration. The fresh air system needed to be opened continuously for 4 hours to stabilize the CO2 concentration, and the decrease rate could reach 53.6%. Whereas, it took only 14 minutes for natural ventilation to reduce the indoor CO2 concentration by 54.3%, but the window opening time was limited in winter. The use of high-efficiency filter fresh air system can ensure indoor comfort and maintain concentration of indoor pollutants at a low level in winter.

Introduction: Red blood cell (RBC) transfusion is associated with adverse outcomes, but there are few studies on the RBC volume. This study aimed to evaluate the relationship between intraoperative RBC volume and postoperative adverse outcomes for on-pump cardiac surgery. Methods: Adult patients undergoing on-pump cardiac surgery from 1 January 2017 to 31 December 2018 were included. Those transfused with more than 6 units of RBC were excluded. The clinical characteristics of four groups with various RBC volume were compared. We analyzed the relationship between RBC volume and adverse outcomes through multivariable logistic regression. Results: 12,143 patients were analyzed, of which 3353 (27.6%) were transfused with 1–6U RBC intraoperatively. The incidence of death, overall morbidity, acute kidney injury and prolonged mechanical ventilation were increased stepwise along with incremental RBC volume. After adjusting for possible confounders, patients transfused with 1–2U were associated with a 1.42-fold risk of death (99% CI, 1.21–2.34, p = 0.01) compared with patients without RBC, patients with 3–4U were associated with a 1.57-fold risk (99% CI, 1.32–2.80, p = 0.005) and patients with 5–6U had a 2.26-fold risk of death (99% CI, 1.65–3.88, p < 0.001). Similarly, the incidence of overall morbidity, acute kidney injury and prolonged mechanical ventilation increased several folds as the RBC numbers increased. Conclusions: There was a significant dose-dependent influence of incremental intraoperative RBC volume on increased risk of adverse outcomes for on-pump cardiac surgery patients. Patient blood management practice should aim to reduce not only transfusion rate but also the volume of blood use. [ABSTRACT FROM AUTHOR]