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This document defines terms related to the structure and processing of inorganic, polymeric, and inorganic-organic hybrid materials from precursors, through gels to solid products. It is divided into four sections – precursors, gels, solids, and processes – and the terms have been restricted to those most commonly encountered. For the sake of completeness and where they are already satisfactorily defined for the scope of this document, terms from other IUPAC publications have been used. Otherwise, the terms and their definitions have been assembled in consultation with experts in the relevant fields. The definitions are intended to assist the reader who is unfamiliar with sol-gel processing, ceramization, and related technologies and materials, and to serve as a guide to the use of standard terminology by those researching in these areas.

The widespread use of thermal analysis (TA) by scientists as a laboratory technique carries with it a working vocabulary. This document is intended to provide those working in the field with a consistent set of definitions to permit clear and precise communication as well as understanding. Included in the document are the definitions of 13 techniques, 54 terms within the glossary, as well as symbols and units.

Perovskites are investigated as potential working materials in new technologies, such as solid oxide fuel cells, thermochemical energy storage, and magnetic refrigerators. They are interesting due to their application properties, such as electrical conductivity, ferromagnetic properties, and reducibility. Properties of perovskites can be improved by doping and the formation of structural defects. The aim of this work was to investigate the possibility of preparing Sr-doped lanthanum manganite with the chemical formula La0.5Sr0.5MnO3 by coprecipitation procedure, and to analyse the observed phase separation. The material was prepared by coprecipitation procedure in which sources of metal cations (La3+, Sr2+, Mn2+) were dissolved in 0.5 M HNO3. The nitrate solution was added dropwise in 10 wt% NH4HCO3 solution, both solutions being heated to 65 °C. To achieve coprecipitation of all present metal cations, the pH value was maintained at 8 by the addition of aqueous ammonia. The obtained precipitate was filtered and dried to obtain the precursor powder. One part of the prepared powder was calcined at 1200 °C/2 h (sample CL_Sr0.5_p), while the other part was pressed into a tablet and sintered in the same conditions (sample CL_Sr0.5_tab). Even though FTIR and PXRD analyses of the sample CL_Sr0.5_p (Figs. 1A-C) showed the formation of the pure phase, light and dark spots were observed during the SEM analysis of the tablet (CL_Sr0.5_tab) fracture surface (Fig. 2). These spots were analysed by energy-dispersive spectroscopy (EDS). EDS analysis (Table 1) showed that the light spots were SrMnO3 phase, while the dark spots were La0.76Sr0.24MnO3 phase. The tablet was then ground and FTIR and PXRD analyses were conducted. The obtained FTIR results (Figs. 1A and 1B) showed some bands characteristic for the SrMnO3 phase, and low-intensity maxima originating from the SrMnO3 phase were observed on the diffractogram (Fig. 1C) of CL_Sr0.5_tab sample, confirming the existence of separated phase. This was additionally investigated by the Rietveld refinement analysis (Table 1), and it was determined that Sr concentration was 0.24 instead of the targeted 0.5. Therefore, the La0.76Sr0.24MnO3 phase was formed, while the rest of added strontium during the synthesis crystallised in the SrMnO3 phase. Since successful preparation of La0.5Sr0.5MnO3 by hydrothermal synthesis was reported by multiple authors, it can be concluded that the coprecipitation procedure is not suitable for high concentration doping of LaMnO3 due to the separation of Sr into the secondary phase, especially when in tablet form. [ABSTRACT FROM AUTHOR]

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Due to constant contact with water and harmful chemicals, hairdressers are at high risk of developing occupational skin diseases (OSD), which in 90% of cases are manifested as irritative or allergic contact dermatitis of hands and forearms. The period from the beginning of exposure to onset of skin symptoms is very short averaging 2.1 years, meaning that symptoms may already be present during apprenticeship. The aim of this paper is to evaluate the effectiveness of pre-school medical examinations as primary prevention tool for OSD among hairdressing apprentices. This survey was conducted in 2015 at a vocational school for hairdressers in Zagreb. All 128 third-grade hairdressing apprentices were invited to participate, and 101 female apprentices with an average age of 17 responded. Data were collected using survey questions regarding the content of the medical examination that pupils underwent before enrolment in the programme. Eighty-nine (88%) apprentices stated they were examined by a physician before enrolment: 48 (54%) by an occupational medicine specialist, 5 (6%) by a general practitioner, 11 (12%) by a school medicine specialist and 19 (21%) did not remember the specialist. Out of 78 apprentices who recounted the details of the examination, 48 (62%) had their skin examined and 54 (69%) were asked if they had any allergies. Results indicate a weakness in conducting health examinations for vocational schools. Consequently, pupils with pre-existing skin problems are allowed to choose high-risk occupations which may worsen their symptoms or facilitate development of OSD. There is a need to strengthen and standardize the content of the examinations prior to enrolment in schools as the first step in vocational guidance, choice of profession, and long-term preservation of working ability. [ABSTRACT FROM AUTHOR]

Preparation of photocatalytically active ZnO layer by chemical bath deposition was investigated. Layers of layered basic zinc acetate (LBZA) were successfully deposited on substrates of varying morphologies, and the substrate hydrolysis led to formation of thicker and better adhering layers. However, the process was quite sensitive to variations in conditions, which makes coating of larger surfaces more challenging. Photocatalytic activity of ZnO layers obtained from LBZA by calcining had poor reproducibility, varying up to 50 % without obvious regularity. [ABSTRACT FROM AUTHOR]

The aim of this review article is to point out to the danger for workers who, by the nature of their occupation, spend most of their working hours outdoor and are exposed to sunlight that increases their risk of skin cancer. Exposure to sunlight during outdoor work increases the average annual dose of UV radiation for 4-5 times compared to people who do not work in the sun, which in outdoor workers significantly increases the risk for the occurrence of actinic keratosis, basal-cell skin cancer and squamous-cell skin cancer. It is considered that the risk for the occurrence of these disorders is doubled if the total lifetime UV radiation dose for persons occupationally non exposed to sun (130 SED annually) is exceeded by 40%. In the EU countries, including Croatia, the introduction of UV radiation personal dosimetry for outdoors workers is in progress. In order to prevent skin cancer caused by occupational UV exposure, it is necessary to implement preventive measures for outdoor workers. Minimum standards for prevention at the EU level include the application of personal protection measures (sunglasses, headgear, clothing, creams with sun protective factor) and health and safety educational programs implemented in the curricula of secondary high schools, and provided to workers at risky workplaces. Skin cancers or multiple actinic keratosis can be recognized as an occupational disease if: 1) diagnosis of squamous-cell skin cancer or basal-cell skin cancer or multiple actinic keratosis (minimum 6 changes) is histologically confirmed; 2) the changes are expressed in occupationally exposed areas of the skin; 3) the history of the disease reveals sufficient occupational exposure to UV radiation. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the cases of diagnosed occupational disease (OD) in the Occupational Medicine of the Institute for Medical Research and Occupational Health Ltd. for a period 2010 to 2014. A review of archived data and voluntary telephone survey for collecting data about the employment status of patients after diagnosed OD were performed. In the period 2010 to 2014, OD was diagnosed in 55 patients. The most often diagnosed were skin OD (N=19), arm overuse syndromes (N=17), asthma and rhinitis (N=10). The most common skin OD was allergic contact dermatitis (N=15), most frequently found in hairdressers (N=5). Carpal tunnel sindrome was the most common overuse syndrome (N=15), most frequently found in textile workers (N=5). Respiratory disorders were most common in health care workers (N=3). Telephone survey was answered by 46 patients. After the diagnosed OD, 21 (46%) patients were employed by the same or another employer: the change of workplace occurred in 14 (30%) patients, in 1 case after retraining, while 7 (15%) patients are still working at the same workplace. Twelve (26%) patients were retired after diagnosed OD: 11 with disability pension or early retirement. Thirteen (28%) patients are unemployed: 11 got fired after diagnosed OD, and the retraining was done in 3 cases. The results indicate an inadequate rehabilitation of workers with diagnosed OD. The change of workplace occurred in only 30% of patients, and retraining in only 4 (9%) cases. The majority of patients are unemployed, retired early or employed at the same workplace that caused OD. [ABSTRACT FROM AUTHOR]