Redetermination of K4[Bi2Cl10]·4H2O

In comparison with the previous refinement of tetra­potassium di-μ-chlorido-bis­[tetra­chloridobismuthate(III)] tetra­hydrate [Volkova, Udovenko, Levin & Shevchenko (1983). Koord. Khim. 9, 356–360], the current redetermination reveals anisotropic displacement parameters for all non-H atoms, localization of the H atoms, and higher precision of lattice parameters and inter­atomic distances. The crystal structure is built up of edge-sharing [Bi2Cl10]4− double octa­hedra with the bridging Cl atoms situated on a mirror plane, three K+ counter-cations (two of which are on mirror planes), and two water mol­ecules that are solely coordinated to the K+ cations. These building units are linked into a three-dimensional network structure. Additional O—H⋯Cl hydrogen bonds between the water mol­ecules and the complex anions stabilize this arrangement

Dynamic Modelling by Bond Graph Approach of Convective Drying Phenomena

Drying operations play an important role in food industries. They are often the last operation of the process of manufacturing a product, with a strong influence on the final quality. The processes are numerous and depend on the type and amount of product to be dried and water to be evaporated, the desired final quality, or the desired functionality for the dried product. In this chapter, we present a modeling study of heat transfer during drying a moist agricultural product placed in a hot air flow in a tunnel dryer with partial solar heating. The bond graph approach has been used for system modeling, and it is an object-oriented graphical approach based on an energetic description between subsystems. Some drying tests have been carried out on tomatoes and the experimental results are compared with the theoretical results for the validation of the developed model

Wavelet-Based Prediction for Governance, Diversi cation and Value Creation Variables

We study the possibility of completing data bases of a sample of governance, diversification and value creation variables by providing a well adapted method to reconstruct the missing parts in order to obtain a complete sample to be applied for testing the ownership-structure / diversification relationship. It consists of a dynamic procedure based on wavelets. A comparison with Neural Networks, the most used method, is provided to prove the efficiency of the here-developed one. The empirical tests are conducted on a set of French firms

Wavelet-Based Prediction for Governance, Diversi cation and Value Creation Variables

We study the possibility of completing data bases of a sample of governance, diversification and value creation variables by providing a well adapted method to reconstruct the missing parts in order to obtain a complete sample to be applied for testing the ownership-structure / diversification relationship. It consists of a dynamic procedure based on wavelets. A comparison with Neural Networks, the most used method, is provided to prove the efficiency of the here-developed one. The empirical tests are conducted on a set of French firms

Energy Management of a Hybrid Photovoltaic-Wind System with Battery Storage: A Case Report

This work presents a case report related to the management and the monitoring of a hybrid photovoltaic-wind system with battery energy storage, installed at the administrative offices building of the municipality of Valderice (Italy) within the framework of the Italy-Tunisia ENPI cooperation project Le Développement Durable Dans la Production Energétique Dans le Territoire (DE.DU.ENER.T.). The paper describes the hybrid system and briefly reports the monitoring data for a whole year, comparing the real production with the expected one and evaluating some performance indexes of the system. The performance indexes are very simple and have been defined only with the purpose of showing the advantages of distributed generation. Then, two different control logics for the battery energy storage systems are compared in order to define the most suitable management of the local energy resources, in presence of different Time-of-Use electricity tariffs. In particular, the two logics are compared by varying the difference between the electricity prices in peak hours and in off-peak hours and the rate between the electricity consumption of the building and the battery energy storage’s capacity

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Etude numerique de la convection naturelle en cavite tridimensionnelle

SIGLECNRS T 56610 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Thermal and electrical performance evaluation of hybrid air PV/T collector – numerical analysis and experimental study

The photovoltaic-thermal (PV/T) hybrid collector is the most generative technology solar energy, which has been invented to utilise electrical energy and heat from the solar system. This paper presents a numerical analysis and experimental validation of the thermal and electrical behaviour of the air PV/T collector based on the geometric design and the Tunisia climate conditions. PV/T system has lower thermal efficiency and higher electrical efficiency (14%) at high wind speeds. To improve the thermal efficiency, a sensitivity analysis studied across a range of the air channel depth (0.01–0.08 m) with different air mass flow rate. It was concluded that the thermal energy for a PV/T air system depends on the optimal depth and variations in mass flow rate

Benchmarking and economic analysis of the impact of geometric structural design on the thermoelectric performance of air‐cooled photovoltaic thermal systems

Abstract For a sustainable system to be designed with the lowest possible cost, photovoltaic thermal (PV/T) system efficiency and heat transmission must be increased. The performance of each hybrid PV/T air system was examined using four air PV/T models with various geometric configurations. The examination of the various mathematical models revealed how each geometry configuration affected each system's performance. Air PV/T arrangements with expanded surfaces, like fins, enhance thermoelectric performance. According to the findings, the thermal efficiencies of finned absorber PV/T and finned Tedlar PV/T are, respectively, 80.3 and 77.54%. Additionally, the figures for electrical efficiencies are 11.88 and 11.93%, respectively. For these two types of PV/T systems, the annual energy output has increased and now stands at roughly 3242 and 3316 kWh/m2, respectively. Additionally, compared to other PV/T systems, the finned Tedlar PV/T system offers higher profitability in terms of cost and revenue according to an economic research

Kinetic study of the convective drying of spearmint

This work presents the kinetic study of the convective drying of Tunisian spearmint in two manners. The traditional protocol which consists in carrying out drying experimental tests at constant temperatures 40–45–50–55 °C and a new protocol which consists in carrying out these tests at variable temperatures in an increasing and decreasing way between 40 °C and 55 °C. All the experimental drying curves show only a falling drying rate period. The main factor in controlling this rate is found to be the drying air temperature. The mode at variable temperatures in an increasing way is more performant and more efficient than the mode at decreasing way or at constant temperature. These experimental curves are fitted to a number of mathematical models. The Midilli–Kucuk drying model is found as the best model which suitably follows the drying curves of spearmint. The characteristic drying curve of spearmint is determined and compared with the modes at variable temperatures. Those at constant temperature and increasing temperature are very close with a correlation coefficient (R2) of 0.8 and Chi-square (χ2) of 0.014, whereas the decreasing mode is a little distant due to the problem of rehumidification at the drying end. Initial moisture has a great influence on a characteristic drying curve