The gravure printing process is widely utilized for large-scale, high-quality, multi-colored printing tasks executed at high press speeds. This includes a diverse range of products such as art books, greeting cards, currency, stamps, wallpaper, magazines, and more. This thesis addresses the fire risks associated with gravure printing, acknowledging the use of highly flammable materials and the potential for static charge-related incidents. Despite its prevalence, there is limited research on fire prevention and control in gravure printing. The study employs field observations, stakeholder interviews, and an extensive review of literature on fire risk and control in printing press operations in India. It analyzes the causes of fires using the fire triangle model, emphasizing the role of heat, combustible materials, and oxygen in fire incidents within the printing press environment. The thesis categorizes preventive measures into fire prevention and fire suppression actions, focusing on reducing fire load, static charge mitigation, and implementing firefighting systems. It observes that poor housekeeping, lack of awareness, and inadequate emergency control plans contribute significantly to fire hazards in press facilities. Additionally, the research identifies key factors such as high press temperatures, low humidity, improper storage, and inadequacies in firefighting systems as potential causes of fires. It emphasizes the need for optimal environmental conditions, proper storage practices, and effective firefighting infrastructure within press facilities. The study concludes with comprehensive guidelines for loss prevention and control, including management programs, housekeeping, operator training, pre-emergency planning, preventive maintenance, and plant security. It also addresses safety measures specific to gravure printing presses, such as automatic sprinkler systems, fire hydrant system, carbon dioxide flooding systems, and portable fire extinguishers. In summary, this thesis provides valuable insights into the multifaceted nature of fire risks in gravure printing presses and recommends a holistic approach for effective fire prevention and control.
This study focuses on the competency structure factors of elementary school English teachers under China’s new curriculum standards, aiming to reveal the core competencies that teachers should possess in the context of education in the new era. Through the comprehensive application of qualitative interviews and quantitative questionnaire survey methods, this study provides an in-depth analysis of the competency structure of primary English teachers. It was found that the competency structure of elementary school English teachers is mainly composed of six dimensions: professionalism, personality traits, teaching ability, student views, teaching organization strategy and research ability. These dimensions work together to influence teachers’ teaching effectiveness and students’ learning effectiveness. The study also found that there were significant differences in the competency characteristics of elementary school English teachers across gender, teaching experience and educational qualifications. In general, this study provides a theoretical basis and practical guidance for the professional development of elementary school English teachers, which can help to improve the quality of teachers’ teaching and promote the comprehensive development of students.
Alginate-silver nanocomposites in the form of spherical beads and films were prepared using a green approach by using the aqueous extract of Ajwa date seeds. The nanocomposites were fabricated by in situ reduction and gelation by ionotropic crosslinking using calcium ions in solution. The rich phytochemicals of the date seed extract played a dual role as a reducing and stabilizing agent in the synthesis of silver nanoparticles. The formation of silver nanoparticles was studied using UV-Vis absorption spectroscopy, and a distinct surface plasmon resonance peak at 421 nm characteristic of silver nanoparticles confirmed the green synthesis of silver nanoparticles. The morphology of the nanocomposite beads and film was compact, with an even distribution of silver nanoclusters. The catalytic property of the nanocomposite beads was evaluated for the degradation of 2-nitrophenol in the presence of sodium borohydride. The degradation followed pseudo-first-order kinetics with a rate constant of 1.40 × 10−3 s−1 at 23 ℃ and an activation energy of 18.45 kJ mol−1. The thermodynamic parameters, such as changes in enthalpy and entropy, were evaluated to be 15.22 kJ mol−1 and −197.50 J mol−1 K−1, respectively. The nanocomposite exhibited properties against three clinically important pathogens (gram-positive and gram-negative bacteria).
The objective of this work was to evaluate the combined effect of bovine manure, Pseudomonas putida and Trichoderma aureoviride on the development of lettuce (Lactuca sativa). The promotion of plant growth by microorganisms may be a viable and sustainable alternative for lettuce crop management. The experimental design was entirely randomized with five treatments: T0 (witness without fertilization, P. putida and T. aureoviride), TE (cattle manure), TEB (cattle manure + P. putida), TEF (cattle manure + T. aureoviride), TEFB (cattle manure + P. putida + T. aureoviride) and ten repetitions each. The following variables were analyzed: germination velocity index (GVI), first count (FC), germination percentage (GP), leaf area index and productivity. The TEFB treatment proved to be a viable alternative for the production of lettuce, especially for small producers, since all the vegetable production in the region comes from family farming.
Introduction: Chest trauma has a high incidence and pneumothorax is the most frequent finding. The literature is scarce on what to do with asymptomatic patients with pneumothorax due to penetrating chest trauma. The aim of this study was to evaluate what are the findings of the control radiography of patients with penetrating chest trauma who are not initially taken to surgery, and their usefulness in determining the need for further treatment. Methods: A retrospective cohort study was performed, including patients older than 15 years who were admitted for penetrating chest trauma between January 2015 and December 2017 and who did not require initial surgical management. We analyzed the results of chest radiography, the time of its acquisition, and the behavior decided according to the findings in patients initially left under observation. Results: A total of 1,554 patients were included, whose average age was 30 years, 92.5% were male and 97% had a sharp weapon wound. Of these, 186 (51.5%) had no alterations in their initial X-ray, 142 had pneumothorax less than 30% and 33 had pneumothorax greater than 30 %, hemopneumothorax or hemothorax. Closed thoracostomy was required as the final procedure in 78 cases, sternotomy or thoracotomy in 2 cases and discharged in 281. Conclusion: In asymptomatic patients with small or moderate pneumothorax and no other significant lesions, longer observation times, radiographs and closed thoracostomy may be unnecessary.
The heat collection evaporator was modeled based on equilibrium homogeneous theory, and the Runge-Kutta calculation method was used to analyze and solve the flow in the heat collection evaporator. The influence of environmental factors such as solar irradiance, ambient temperature and wind speed on the variation of refrigerant pressure in two kinds of heat collecting evaporator was analyzed under the set working conditions. The results show that the solar energy irradiance has a great influence on the pressure drop in the tube of serpentine heat collecting evaporator, and the maximum pressure drop of the refrigerant in the tube is 16.3%, minimum pressure drop is 7.8%. However, it has little influence on the pressure drop of the tube sheet evaporator. The maximum pressure drop in the refrigerant tube of the tube sheet evaporator is 4.8%, minimum pressure drop is 1.8%. When the irradiance reaches 800 W/m2, the refrigerant in the serpentine-tube evaporator has been completely vaporized at 6 m, it’s completely vaporized at 3 m.
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