Low Temperature MOCVD-Processed Alumina Coatings

We first present a Review about the preparation of alumina as thin films by the technique of MOCVD at low temperature (550°C and below). Then we present our results about thin films prepared by the low pressure MOCVD technique, using aluminium tri-isopropoxide as a source, and characterized by elemental analysis (EMPA, EDS, ERDA, RBS), FTIR, XRD and TGA. The films were grown in a horizontal, hot-wall reactor, with N2 as a carrier gas either pure or added with water vapour. The deposition temperature was varied in the range 350-550°C. The films are amorphous. Those prepared at 350°C without water added in the gas phase have a formula close to AlOOH. Those deposited above 415°C are made of pure alumina Al2O3. When water is added in the gas phase, the films are pure alumina whatever the deposition temperature

Protective Alumina Coatings by Low Temperature Metalorganic Chemical Vapour Deposition

Alumina thin films were processed from aluminium tri-iso-propoxide in a horizontal, with N2 as a carrier gas, occasional addition of water in the gas phase, deposition temperature in the range 350-700°C, total pressure 0.67 kPa (2 kPa when water was used). The films do not diffract X-ray when prepared below 700°C. At 700°C, they start to crystallize as γ-alumina. EDS, EPMA, ERDA, RBS, FTIR and TGA revealed that films prepared in the range 350- 415°C, without water in the gas phase, have an overall composition Al2O3-x(OH)2x, with x tending to 0 with increasing temperature. Al2O3 is obtained above 415°C. When water is added in the vapour phase, the film composition is Al2O3, even below 415°C. Coatings deposited in these conditions show promising protection properties

Phase Transformations of Metallorganic Chemical Vapor Deposition Processed Alumina Coatings Investigated by In Situ Deflection

Phase transformations of Al2O3 films, deposited by metallorganic chemical vapor deposition from aluminium tri-isopropoxide on AISI 301 stainless steel, were investigated using an original technique of deflection associated with X-ray diffraction and electron microscopy. The samples were first oxidized at 1123 K in air to obtain a 0.9 m thick Cr2O3 protective oxide film on one side of the samples. Then, 1 m thick amorphous Al2O3 films were deposited on the opposite side at 823 K and 2 kPa. The deflection of such dissymmetrical samples was recorded during anisothermal treatments, consisting in slow heating to 1173 K in Ar atmosphere. The coefficient of thermal expansion of both the Cr2O3 and the amorphous Al2O3 films was determined to be 710−6 K−1 and 14.7 10−6 K−1, respectively. Crystallization kinetics of amorphous to mainly –Al2O3 become significant at temperatures equal or greater than 983 K. Transformation of metastable Al2O3 to –Al2O3 is initiated below 1173 K. It is demonstrated that deflection is a powerful tool for investigating the behavior of thin films deposited on a substrate and especially to reveal transformations occurring in these films during heat-treatments

Aluminium tri-iso-propoxide: Shelf life, transport properties, and decomposition kinetics for the low temperature processing of aluminium oxide-based coatings

Aluminium tri-iso-propoxide (ATI) is a common precursor for the MOCVD of alumina coatings. However, little is known on its long term stability while its saturated vapour pressure in function of the temperature is controversial. The present contribution deals with these questions through FTIR, TGA and vapour pressure measurements. Low pressure MOCVD from ATI was performed in the temperature range 250–700 °C. Whereas the pyrolytic decomposition of ATI leads to hydroxo species free alumina films above 415 °C, it is shown in this paper that the thermal decomposition of ATI in the presence of water vapour yields pure alumina films at temperatures as low as 300–350 °C. The films prepared in the range 250–700 °C do not diffract X-rays. Arrhenius plots for both pyrolytic (Ea∼12 kJ/mole) and water assisted (Ea∼9 kJ/mole) decomposition reveal diffusion-limited processes with higher growth rate values in the former case

Role of in vivo reflectance confocal microscopy in the analysis of melanocytic lesions

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Artificial intelligence and architectural design : an introduction

Descripció del recurs: 27 juliol 2022The aim of this book on artificial intelligence for architects and designers is to guide future designers, in general, and architects, in particular, to support the social and cultural wellbeing of the humanity in a digital and global environment. This objective is today essential but also extremely large, interdisciplinary and interartistic, so we have done just a brief introduction of the subject. We will start with the argument fixed by the Professor Jonas Langer in his web some years ago, that we have defined as: “The Langer’s Tree”.Primera edició

Treatment of axial spondyloarthritis patients with biologic disease-modifying anti-rheumatic drugs in 2022 - data from the Romanian Registry of Rheumatic Diseases

Objective. The objective of this cross-sectional study was to analyze data available in the Romanian Registry of Rheumatic Diseases (RRBR) in 2022 for axial spondyloarthritis (axSpA) patients treated with biologic disease modifying anti-rheumatic drugs (bDMARDs). Methods. From the RRBR electronic database were collected multiple variables, including patient’s demographic and clinical characteristics, treatment characteristics, patterns of treatment use (initiations, continuations, switching, tapering), and treatment efficacy data of axSpA patients, from 1 January 2022 to 31 December 2022. Results. In 2022, a total of 4315 axSpA patients were registered in the RRBR database: 70% were men, 48.4 years mean age, 13.3 years mean disease duration, 90% with radiographic axSpA, with high prevalence of extra-musculoskeletal manifestations and cardiovascular comorbidities. Most patients (88%) were treated with a tumor necrosis factor inhibitor (TNFi), usually in monotherapy. The most frequently prescribed bDMARDs were adalimumab (36%), etanercept (32%) and secukinumab (12%). The uptake of biosimilars reached one third of patients from molecules with available biosimilars in 2022. Most patients had a good clinical response, irrespective of clinical form, disease duration, type of medication or line of treatment. Medication switching was needed in 10% of patients, the main reason for switching was secondary loss of efficacy. Medication tapering was implemented in 11% of patients, and it was successful in 90% of cases. Conclusion. Data from RRBR provide a valuable real-world view of clinical practice at the national level regarding biologic treatment of axSpA patients

Disease severity, treatment patterns, and quality of life in patients with moderate-to-severe psoriasis routinely managed with systemic treatment: results of the CRYSTAL observational study in Central and Eastern European countries

Psoriasis is a common, life-long skin disease with a significant negative health and societal impact. Data on rates of disease control and treatment strategies are lacking in Central and Eastern European countries. We aimed to describe the real-world disease severity, control, and treatment strategies for psoriasis in patients from Central and Eastern European countries. CRYSTAL (EUPAS36459) was a cross-sectional, retrospective study in adults (18–75 years) from Bulgaria, Estonia, Hungary, Latvia, Lithuania, Romania, and Russia. We enrolled patients with moderate-to-severe psoriasis receiving continuous systemic treatment for ≥24 weeks. We used the Psoriasis Area and Severity Index (PASI) to describe disease severity and the Dermatology Life Quality Index (DLQI) to assess quality of life (QoL) and collected other outcomes [psoriasis work productivity and activity impairment (WPAI-PSO), patient satisfaction] at enrollment. Analyses were descriptive. A total of 690 patients were included in the analyses. Median disease duration was 11.8 years. Current treatment was monotherapy for most patients (95.8%) with either biological (BIO group; 88.4%) or conventional (NON-BIO group; 7.4%) agents. Mean (± standard deviation) absolute PASI scores were 3.5 ± 5.7, 3.1 ± 5.3, and 6.6 ± 7.4 in the overall population, the BIO group, and the NON-BIO group, respectively. Among patients treated with monotherapy, absolute PASI scores ≤1, ≤3, and ≤5 were observed for 44.1%, 72.0%, and 82.6% of BIO patients and 21.6%, 33.3%, and 49.0% of NON-BIO patients. Mean DLQI total score was 3.3 ± 5.1; higher scores were noted for higher absolute PASI. The most impacted WPAI-PSO domain was presenteeism; for all domains, impact increased with increased absolute PASI. A total of 91.8% of BIO patients and 74.5% of NON-BIO patients were satisfied with the current treatment. We observed a better disease control in BIO than NON-BIO patients. However, around half of BIO patients did not reach clear skin status and reported an impact on QoL. An improvement in treatment strategies is still needed in Central and Eastern European countries to optimize outcomes of moderate-to-severe psoriasis