Analysis of the mean radiant temperature in well insulated buildings: experimental comparison between low temperature radiator and floor radiant heating system; internal reflecting solar shading effect

The paper reports the results of an experimental and analytic study on the behaviour of an internal environment characterized by high thermal insulation and alternative heating systems, low temperature radiator or floor heating system. The aims of the research are: to analyse the wintertime discomfort caused by the window in the two types of thermal plant; to verify the effectiveness of the adoption of internal reflective solar shadings to reduce the discomfort penetration depth. To that aims an experimental campaign was carried out in a full scale test room equipped with a window under controlled conditions. Wall surface temperatures, heat fluxes, globe temperature distribution, air temperature distribution and air velocity near the window were measured. Thermal discomfort was assessed by the analysis of the mean radiant temperature’s distribution (TMR). Numerical simulation were performed with a commercial code able to calculate the mean radiant temperature for different position along different axes. Experimental and numerical results were compared to check the reliability of the numerical analysis. The experimental results showed that at a distance of 1 m from the window the globe temperature was lower than 19°C. This occurs when the room was heated by floor radiant heating systems. The discomfort penetration depth decreases to 0,50 m with low temperature radiator and to 0,30 m with internal reflective solar shading. Internal reflective solar shading system reduces the variation of the mean radiant temperature near the window and the heat losses through the window

Microcellular Thermosetting Polyurethane Foams

Thermosetting polyurethane foams are nowadays produced with typical bubble size, d > 150 μm, with plenty of room for improvement towards the cellular structure refinement, to gain, among others, in the thermal insulation performances. We herein report a first example of a microcellular thermosetting polyurethane foam, i. e. with bubble size below 5 μm, produced via the gas foaming technology. In particular, high-pressure CO2, N2 and their mixtures were utilized as blowing agents: solubilized separately into the polymer precursors, they were brought into a supersaturated state by a pressure reduction to induce the bubble nucleation and growth. To achieve microcellular foams, we made use of a novel two-stage pressure reduction program, concurrent to the polymer curing. The first stage is a pressure quench O (10-2 s) from the saturation pressure to an intermediate pressure to induce the nucleation of a large amount of dense bubbles. The second stage is a slow O (102 s) further pressure decrease to ambient pressure, allowing for a slow bubble growth, designed to reach ambient pressure exactly when the curing reached completion

Light-enhanced liquid-phase exfoliation and current photoswitching in graphene-azobenzene composites

Multifunctional materials can be engineered by combining multiple chemical components, each conferring a well-defined function to the ensemble. Graphene is at the centre of an ever-growing research effort due to its combination of unique properties. Here we show that the large conformational change associated with the trans-cis photochemical isomerization of alkyl-substituted azobenzenes can be used to improve the efficiency of liquid-phase exfoliation of graphite, with the photochromic molecules acting as dispersion-stabilizing agents. We also demonstrate reversible photo-modulated current in two-terminal devices based on graphene-azobenzene composites. We assign this tuneable electrical characteristics to the intercalation of the azobenzene between adjacent graphene layers and the resulting increase in the interlayer distance on (photo)switching from the linear trans-form to the bulky cis-form of the photochromes. These findings pave the way to the development of new optically controlled memories for light-assisted programming and high-sensitive photosensors

Road Traffic Pollution and Childhood Leukemia: A Nationwide Case-control Study in Italy.

The association of childhood leukemia with traffic pollution was considered in a number of studies from 1989 onwards, with results not entirely consistent and little information regarding subtypes. AIM OF THE STUDY: We used the data of the Italian SETIL case-control on childhood leukemia to explore the risk by leukemia subtypes associated to exposure to vehicular traffic. METHODS: We included in the analyses 648 cases of childhood leukemia (565 Acute lymphoblastic-ALL and 80 Acute non lymphoblastic-AnLL) and 980 controls. Information on traffic exposure was collected from questionnaire interviews and from the geocoding of house addresses, for all periods of life of the children. RESULTS: We observed an increase in risk for AnLL, and at a lower extent for ALL, with indicators of exposure to traffic pollutants. In particular, the risk was associated to the report of closeness of the house to traffic lights and to the passage of trucks (OR: 1.76; 95% CI 1.03-3.01 for ALL and 6.35; 95% CI 2.59-15.6 for AnLL). The association was shown also in the analyses limited to AML and in the stratified analyses and in respect to the house in different period of life. CONCLUSIONS: Results from the SETIL study provide some support to the association of traffic related exposure and risk for AnLL, but at a lesser extent for ALL. Our conclusion highlights the need for leukemia type specific analyses in future studies. Results support the need of controlling exposure from traffic pollution, even if knowledge is not complete

Risk of childhood leukaemia and non-Hodgkin's lymphoma after parental occupational exposure to solvents and other agents: the SETIL Study

AIM: In the context of the Italian Multicentric Epidemiological Study on Risk Factors for Childhood Leukaemia and Non-Hodgkin's Lymphoma (SETIL), the risk of childhood cancer was investigated in relation to parental occupational exposures. METHODS: All cases of childhood leukaemia and non-Hodgkin's lymphoma (NHL) in children aged 0-10 years were identified. Controls were chosen at random from the local population in each region. Parents were interviewed using a structured questionnaire. The collected data were blindly reviewed by expert industrial hygienists in order to estimate exposure to a list of agents. Statistical analyses were performed for each agent using unconditional multivariable logistic regression models, taking into account timing of exposure. RESULTS: 683 cases of acute childhood leukaemia, 97 cases of NHL and 1044 controls were identified. Increased risk of childhood leukaemia was found for maternal exposure to aliphatic (OR 4.3) or aromatic hydrocarbons (OR 3.8) in the preconception period, and for paternal exposure to diesel exhaust (OR 1.4), lead exposure (OR 1.7) and mineral oils (OR 1.4)[corrected]. Risk of NHL appeared to be related to paternal exposure to oxygenated solvents (OR 2.5) and petrol exhaust (OR 2.2). CONCLUSIONS: We found increased risk for childhood leukaemia associated with maternal occupational exposure to aromatic and aliphatic hydrocarbons, particularly in the preconception period; increased risks were also observed for paternal exposure to diesel exhaust fumes, mineral oils and lead. The risk of NHL appeared to be related to paternal exposure to oxygenated solvent and petrol exhausts

Italian multicentricepidemiological case control strudy on risk factors for childhood leukemia,non hodgkin limphoma and neuroblastoma:study population and prevalence of risk factors in Italy

Background Aetiology of childhood leukaemia and childhood neoplasm is poorly understood. Information on the prevalence of risk factors in the childhood population is limited. SETIL is a population based case/control study on childhood leukaemia, conducted with two companion studies on non-Hodgkin Lymphoma (NHL) and neuroblastoma. The study relies on questionnaire interviews and 50 Hz magnetic field (ELF-MF) indoor measurements. This paper discusses the SETIL study design and includes descriptive information. Methods The study was carried out in 14 Italian regions (78.3% of Italian population aged 0?10). It included leukaemia, NHL and neuroblastoma cases incident in 0?10 year olds in 1998-2001,registered by the Italian Association of Paediatric Haematology and Oncology (AIEOP)(accrual over 95% of estimated incidence). Two controls for each leukaemia case were randomly sampled from the Local Health Authorities rolls, matched by gender, birthdate and residence. The same controls were used in NHL and neuroblastoma studies. Parents were interviewed at home on: physical agents (ELF-MF and ionizing radiation), chemicals (smoking, solvents, traffic, insecticides), occupation, medical and personal history of children and parents, infectious diseases, immunizations and associated factors. Occupational exposure was collected using job specific modules. ELF-MF was measured in the main rooms (spot measurement) and close to child?s bed (48 hours measurement). Results The study included: 683 leukaemia cases (87% ALL, 13% AnLL), 97 NHL, 155 neuroblastomas, and 1044 controls.ELF-MF long term measurements were obtained for 61.1% of controls and 81.6% of leukaemia cases; 8.8% of controls were exposed at over 0.1 microTesla (\u3bcT), 3.5% and 2.1% at respectively over 0.2 and 0.3 \u3bcT. 25% of controls? fathers had smoked over 10 cigarettes/day during the year of conception, varying according to education and region. Maternal smoking was less common (71.4% did not smoke in pregnancy). Maternal passive smoking during pregnancy was reported by 31.2% of controls; the child?s passive smoking for 28.6%. Occupational exposure to solvents was estimated in 18.3% of controls? fathers and 7.7% of mothers. Contact with public was more frequent among mothers (36.1%) than fathers (23.4%). Conclusions SETIL represents a data source on exposure of Italian children to a broad array of potential carcinogenic factors

SETIL: Italian multicentric epidemiological case-control study on risk factors for childhood leukaemia, non hodgkin lymphoma and neuroblastoma: study population and prevalence of risk factors in Italy

BACKGROUND: Aetiology of childhood leukaemia and childhood neoplasm is poorly understood. Information on the prevalence of risk factors in the childhood population is limited. SETIL is a population based case-control study on childhood leukaemia, conducted with two companion studies on non-Hodgkin Lymphoma (NHL) and neuroblastoma. The study relies on questionnaire interviews and 50 Hz magnetic field (ELF-MF) indoor measurements. This paper discusses the SETIL study design and includes descriptive information. METHODS: The study was carried out in 14 Italian regions (78.3% of Italian population aged 0-10). It included leukaemia, NHL and neuroblastoma cases incident in 0-10 year olds in 1998-2001, registered by the Italian Association of Paediatric Haematology and Oncology (AIEOP) (accrual over 95% of estimated incidence). Two controls for each leukaemia case were randomly sampled from the Local Health Authorities rolls, matched by gender, birthdate and residence. The same controls were used in NHL and neuroblastoma studies. Parents were interviewed at home on: physical agents (ELF-MF and ionizing radiation), chemicals (smoking, solvents, traffic, insecticides), occupation, medical and personal history of children and parents, infectious diseases, immunizations and associated factors. Occupational exposure was collected using job specific modules. ELF-MF was measured in the main rooms (spot measurement) and close to child's bed (48 hours measurement). RESULTS: The study included: 683 leukaemia cases (87% ALL, 13% AnLL), 97 NHL, 155 neuroblastomas, and 1044 controls. CONCLUSIONS: SETIL represents a data source on exposure of Italian children to a broad array of potential carcinogenic factors