389 research outputs found
An inspection system for pharmaceutical glass tubes
Abstract: Syringes, vials and carpules for pharmaceutical products are usually made of borosilicate glass. Such containers are made by glass converting companies starting from single glass tubes. These glass containers can suffer from inclusions, air bubbles, stones, scratches and others issues, that can cause subsequent problems like product contamination with glass particulate or cracks in the glass. In recent years, more than 100 million units of drugs packaged in vials or syringes have been withdrawn from the market. As a consequence pharmaceutical companies are demanding an increased delivery of high quality products to manufacturers of glass containers and therefore of glass tubes. An automatic, vision based, quality inspection system can be
devoted to perform such task, but specific process features requires the introduction of ad-hoc solutions: in the production lines tubes significantly vibrate and rotate, and the cylindrical surface of the tube needs to be
inspected at 360 degrees. This paper presents the design, the development and the experimental evaluation of a vision system to control the quality of glass tubes, highlighting the specific solutions developed to manage vibrations and rotations, obtaining a 360 degree inspection. The system has been designed and tested in a real
facility, and proved effective in identifying defects and impurities in the order of tens of microns
Chalcophile Element Constraints on the Sulfur Content of the Martian Mantle
The sulfur content of the Martian mantle is critical to understanding volcanic volatiles supplied to the surface of Mars and possibly climate. In the absence of Martian mantle rocks, sulfur content of the mantle has been inferred from S contents of Martian meteorites or from sedimentary sulfate abundances. Estimates of the sulfur content of the Martian mantle vary from 390-2,000 ppm, all of which are higher than that of the terrestrial mantle (~250 ppm;). Residual sulfide in the Martian mantle controls the distribution of chalcophile elements during partial melting. In this study, we report new analyses of Martian meteorites, and use the incompatible behavior of As, Tl and Pb to infer the sulfide mode of the Martian mantle using a different set of assumptions than those of prior studies
Do nebular fractionations, evaporative losses, or both, influence chondrule compositions?
We have made observations and performed heating experiments to determine the relative importance of several processes which may have influenced the compositions of chondrules. As heating destroys nuclei, the number density of olivine and pyroxene crystals gives an indication of the extent of melting. We determined number densities of Semarkona type I chondrules and converted them to nominal grain size, for use as a measure of intensity of heating. Bulk compositions of the chondrules show correlations with nominal grain size. Na, K, Fe, Ni, P and S decrease as grain size (degree of melting) increases, and we interpret this as evidence of evaporative loss. The evidence is less clear for Mn, Cr and Si. SiO_2/MgO ratios show very large variations even in fine-grained type I chondrules containing FeS, and we interpret those variations as due to nebular fractionations affecting precursors. Experiments show that Na and S losses increase with higher temperatures and lower cooling rates. It is hard to preserve any sulfide at all, without flash heating. Na, however, can be retained at close to chondritic levels (as in type II chondrules) with flash heating and high cooling rate, provided also that the oxygen fugacity is high. Type II chondrules can retain much more Na than type I under identical thermal conditions, because of higher fO_2 (either due to non-nebular gas or possibly internal buffering by FeO content) and melt structure (higher SiO_2/MgO). Gas reduction experiments show that type II compositions can be converted to IB by Fe loss, but evaporative loss of SiO_2 (so as to approach IA composition) is not achieved without prolonged isothermal heating. Precursors of type I and II chondrules were probably close to chondritic in composition, but with higher Fa in the type II case. They consisted of olivine, pyroxene, plagioclase, Fe (Ni) S and carbon compounds, probably with insignificant metal. Sulfur loss generated much chondrule metal in ordinary chondrites. C is a possible alternative to gas reduction to explain dusty relict grains and the lower olivine Fa in the more melted type I chondrules. We agree with J. N. GROSSMAN and J. T. WASSON (Geochim. Cosmochim. Acta, 47,759,1983) that variations in Mg/Si are due to nebular fractionations and with S. HUANG et al. (Icarus, 122,316,1996) that variations in Na and Fe in type I chondrules are mainly due to evaporative losses
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Paris: The slightly altered, slightly metamorphosed CM that bridges the gap between CMs and Cos
A fresh, 1.3 kilo stone was found in Paris. It is a CM chondrite with metal, Fe-sulfide, FeS-rich PCPs and relict mesostasis and is ~3.0 ± 0.1. Petrographic and oxygen isotope evidence indicates that it has affinities with the CO chondrites
Tin Abundances Require that Chassignites Originated from Multiple Magmatic Bodies Distinct from Nakhlites
Meteorites from Mars lack field context but chemical and chronologic studies have revealed remarkable links between nakhlites and chassignites. A widely held consensus is that nakhlites and chassignites originated from a large, single differentiated flow or shallow intrusive [1-5]. An Ar-Ar study assumed multiple flows based on resolvable age differences between meteorites [6], but did not address the possibility of differential cooling in a large, shallowly emplaced intrusion [1]. REE abundances in pyroxenes from nakhlites and Chassigny led [7] to argue for derivation of these rocks from distinct magmas. Volatile abundances (F, Cl, OH) in chlorapatites indicated that the entire suite of nakhlites and chassignites experienced hydrothermal interaction with a single fluid supporting a single body origin [4]. The discovery of a new chassignite, NWA 8694, extended the Mg# range from 80-54, providing a closer link to nakhlites but revealed the petrological difficulty of fractionating a single body of liquid to yield a series of olivine cumulates with such a large Mg# range [8]. When mafic magmas are emplaced into the crust, crustal assimilation can impart distinct elemental signatures if the country rock has experienced sedimentary or hydrothermal processing [9]. In this work, we used Sn abundances of nakhlites and chassignites to show that these rocks were crystallized from distinct magma batches, providing vital contextual clues to their origin
Comprehensive Geriatric Assessment: Application and correlations in a real-life cross-sectional study
Background: The assessment process of elderly people considers all aspects of an individual's life, including physical, mental, and social aspects. Frailty refers to a decline in physiological functions or strengths leading to increased vulnerability to stressors and decreased ability to cope with them. Comprehensive Geriatric Assessment (CGA) is a validated and useful tool in this context to holistically study elderly people. The primary aim of this study was to determine the prevalence of impaired health status in a large geriatric population turning to outpatient service, based on the components of the CGA, and thus to describe its usefulness in real-life clinical practice. The secondary aim of this study was the evaluation of the association between nutritional status, assessed with Mini Nutritional Assessment (MNA)-within the CGA-and cognitive-affective and functional capacities, and multimorbidity. Materials and methods: This real-life, retrospective cross-sectional study included subjects consecutively evaluated from January 2009 to December 2020 at the Geriatric Outpatient Service, University Hospital of Monserrato, Cagliari, Italy. A sum of 3,260 patients were subjected to CGA. Results: Only a small proportion of the sample (2.24%) showed an absence of impairment in cognitive-affective, functional, and nutritional domains. Moderate correlations were found between MNA and several other CGA variables, namely, Geriatric Depression Scale (GDS; ϱ = -0.41, p < 0.0001), Barthel Index of Independence in Activities of Daily Living (ADL) (ϱ = 0.51, p < 0.0001), Instrumental Activities of Daily Living (IADL) (ϱ = 0.43, p < 0.0001), and Performance-Oriented Mobility Assessment (ϱ = 0.44, p < 0.0001). A multiple regression also highlighted these variables as significant regressors of MNA. Finally, malnutrition showed a significant association with depression (odds ratio [OR]: 4.97), dependence on ADL (OR: 19.8) and IADL (OR: 7.04), and falling risk (OR: 5.16). Conclusion: This study has figured out the complex situation in which geriatric care finds itself the complexity and severe impairment of elderly people. The possibilities of intervention are often limited, but the literature confirms the benefits of good nutritional status on the general health status. The data that emerged from our study fit into this assumption, highlighting the close association between the nutritional domain and the other CGA domains
The Germanium Dichotomy in Martian Meteorites
Germanium is a moderately volatile and siderophile element that follows silicon in its compatibility during partial melting of planetary mantles. Despite its obvious usefulness in planetary geochemistry germanium is not analyzed routinely, with there being only three prior studies reporting germanium abundances in Martian meteorites. The broad range (1-3 ppm) observed in Martian igneous rocks is in stark contrast to the narrow range of germanium observed in terrestrial basalts (1.5 plus or minus 0.1 ppm). The germanium data from these studies indicates that nakhlites contain 2-3 ppm germanium, while shergottites contain approximately 1 ppm germanium, a dichotomy with important implications for core formation models. There have been no reliable germanium abundances on chassignites. The ancient meteoritic breccia, NWA 7533 (and paired meteorites) contains numerous clasts, some pristine and some impact melt rocks, that are being studied individually. Because germanium is depleted in the Martian crust relative to chondritic impactors, it has proven useful as an indicator of meteoritic contamination of impact melt clasts in NWA 7533. The germanium/silicon ratio can be applied to minerals that might not partition nickel and iridium, like feldspars. We report germanium in minerals from the 3 known chassignites, 2 nakhlites and 5 shergottites by LAICP- MS using a method optimized for precise germanium analysis
Application of electrochemical impedance for characterising arrays of Bi2S3 nanowires
Electrochemical Impedance Spectroscopy (EIS) was used to characterise the electrical properties of bismuth sulphide (Bi2S3) nanowires (NWs) templated within anodic aluminium oxide (AAO) membranes. A specially engineered cell, with a nominal electrolyte volume of 0.1–0.2 ml, was used to hold and measure the electrochemical impedance of the fragile NW/AAO samples. An equivalent circuit model was developed to determine the filling density of nanowires within the porous templates. The EIS method can be utilised to probe the nanowire filling density in porous membranes over large sample areas, which is often unobtainable using electron microscopy and conductive atomic force microscopy techniques
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