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[en] The manufacturing of a product is connected directly to the amount of carbon emitted in producing electrical energy used by that manufacturing process. A new, simple Carbon Emission Signature, CES™, is proposed. Knowing the CES for a power grid and the energy needed to make a part, the carbon emitted can be found. Examples of single point turning and open die forging are given. Knowing the total carbon emitted for a product, a manufacturer can voluntarily place a Green House Gas label on each product. A customer can then see the amount of Green House Gas emitted in making the product. The format for a Carbon Emissions label is proposed. (author)
[en] The aim of the present work was to prepare 188W/188Re generators based on 188W-heteropolytungstate and hydroxyapatite in order to evaluate their feasibility. Titanium and zirconium 188W-tungstate were synthesized at different pH's of the 188W-tungstante solutions and constructed the 188W/188Re generators. Hydroxyapatite is an anion exchanger with an adsorption capacity about 0.9 % w. A study of the sorption behaviour of W and Re on hydroxyapatite in NaCl medium was evaluated by batch experiments. Our results demonstrated that Re-188 is not adsorbed whereas W-188 is strongly adsorbed in NaCl. From these data, hydroxyapatite 188W/188Re generator systems were then constructed and eluted in NaCl solutions. The titanium and zirconium 188W-tungstate, and hydroxyapatite based 188W/188Re generator performances are presented. (author)
[en] DISIGEG is a synthesis installation of zirconium 99Mo-molybdate gels for 99Mo/99mTc generator production, which has been designed, built and installed at the ININ. The device consists of a synthesis reactor and five systems controlled via keyboard: (1) raw material access, (2) chemical air stirring, (3) gel dried by air and infrared heating, (4) moisture removal and (5) gel extraction. DISIGEG operation is described and dried condition effects of zirconium 99Mo- molybdate gels on 99Mo/99mTc generator performance were evaluated as well as some physical–chemical properties of these gels. The results reveal that temperature, time and air flow applied during the drying process directly affects zirconium 99Mo-molybdate gel generator performance. All gels prepared have a similar chemical structure probably constituted by three-dimensional network, based on zirconium pentagonal bipyramids and molybdenum octahedral. Basic structural variations cause a change in gel porosity and permeability, favouring or inhibiting 99mTcO4− diffusion into the matrix. The 99mTcO4− eluates produced by 99Mo/99mTc zirconium 99Mo-molybdate gel generators prepared in DISIGEG, air dried at 80 °C for 5 h and using an air flow of 90 mm, satisfied all the Pharmacopoeias regulations: 99mTc yield between 70–75%, 99Mo breakthrough less than 3×10−3%, radiochemical purities about 97% sterile and pyrogen-free eluates with a pH of 6. - Highlights: ► 99Mo/99mTc generators based on 99Mo-molybdate gels were synthesized at a semi-automatic device. ► Generator performances depend on synthesis conditions of the zirconium 99Mo-molybdate gel. ► 99mTcO4− diffusion and yield into generator depends on gel porosity and permeability. ► 99mTcO4− eluates satisfy Pharmacopoeias regulations and can be applied for clinical use.
[en] Successive versions of high speed, active silicon pixel detectors with integrated readout electronics have been developed for particle physics experiments using monolithic and hybrid technologies. Various matrices with binary output as well as a linear detector with analog output have been made. The hybrid binary matrix with 1024 cells (dimension 75 μmx500 μm) can capture events at similar 5 MHz and a selected event can then be read out in <10 μs. In different beam tests at CERN a precision of 25 μm has been achieved and the efficiency was better than 99.2%. Detector thicknesses of 300 μm and 150 μm of silicon have been used. In a test with a 109Cd source a noise level of 170 e-r.m.s. (1.4 keV fwhm) has been measured with a threshold non-uniformity of 750 e- r.m.s. Objectives of the development work are the increase of the size of detecting area without loss of efficiency, the design of an appropriate readout architecture for collider operation, the reduction of material thickness in the detector, understanding of the threshold non-uniformity, study of the sensitivity of the pixel matrices to light and low energy electrons for scintillating fiber detector readout and last but not least, the optimization of cost and yield of the pixel detectors in production. ((orig.))
[en] Highlights: • Novel MgO-PCL-chitosan based composite nanofiber membranes were synthesized. • Ultimate tensile strength up to 3 MPa and Young’s modulus up to 25 MPa obtained. • No cytotoxicity observed with 3T3 fibroblast cells. • Nanofibers showed uniform surface morphology, and structural integrity in cell media. - Abstract: The ability to produce composite nanofibers of inorganic particles and synthetic polymers represents a significant advancement in the development of composite materials for potential biomedical applications. In this study, composite nanofibers of magnesium oxide (MgO), poly(ε-caprolactone) (PCL) and chitosan (CS) with diameters in the range of 0.7–1.3 µm were fabricated by electrospinning their blend solutions in trifluroethanol and water. To support the potential use of these nanofibrous membranes for biomedical applications their physicochemical properties such as morphology, mechanical strength, and integrity in aqueous medium, were studied. Cellular compatibility was determined using cell viability assays and microscopy imaging, with the results showing that the nanofibrous membranes support 3T3 cell viability and attachments. The new composite nanofibrous membranes developed in this study have the ability to mimic the physical structure and function of tissue extracellular matrix (ECM) and thus have potential for many tissue engineering applications.