Search results for "Additive"
showing 10 items of 297 documents
From measuring to revealing. 7 Paradigmatic actions for the construction of models as tools of representation
2017
L’esperienza maturata nel corso della ricerca: Progettazione, Organizzazione e Gestione di un nuovo Laboratorio di modellistica: metodologie, materiali e strumenti, (piani cazione, organizzazione e gestione di un nuovo laboratorio di modellazione: metodologie, materiali e strumenti), presso il Politecnico di Milano, è il background di questo articolo proposto per la giornata di studi. Da questa esperienza il testo si concentra sul set-up della seguente dichiarazione: il modello architettonico come strumento di rappresentazione. L’obiettivo è quello di formulare alcune procedure metodologiche, attraverso sette diverse azioni di progetto: scavo, taglio, piegatura, stratificazione, intaglio, m…
High-performing Sn-Co nanowire electrodes as anodes for lithium-ion batteries
2012
Abstract The preparation of Sn 2 Co 3 nanowire arrays (NWs) electrogrown inside the channels of polycarbonate membranes and their characterization as anodes for Li-ion batteries both in half-cell vs. Li and in battery configuration are reported. The Sn 2 Co 3 NW electrodes tested by deep galvanostatic charge/discharge cycles in ethylene carbonate-dimethylcarbonate (1:1) – LiPF 6 1 M displayed 80% capacity retention after 200 cycles at C/2 and 30 °C, and a high charge and discharge rate capability at C-rate from C/3 (0.33 A/g) to 10C (10 A/g) at 30° and 10 °C. Electrodes with the highest alloy loading delivered up to 0.6 mAh cm −2 at C/2. The performance of these electrodes in battery config…
Using coded excitation to maintain signal to noise for FMC+TFM on attenuating materials
2019
Ultrasonic Non-Destructive Evaluation using Full Matrix Capture (FMC) and Total Focusing Method (TFM) is used for high resolution imaging as every pixel is in optimal focus. FMC excites one element in turn, so operates with lower transmitted energy compared to phased array beamforming. The energy at a reflector is further reduced by the broad directivity pattern of the single element. The large number of Tx/Rx A-scans that contribute to each pixel recover the Signal-to-Noise Ratio (SNR) in the final TFM image. Maintaining this in the presence of attenuating materials is a challenge because relevant information in each A-scan signal is buried in the thermal noise, and the TFM process assumes…
Three-Dimensional Bioprinting for Cartilage Tissue Engineering: Insights into Naturally-Derived Bioinks from Land and Marine Sources
2022
In regenerative medicine and tissue engineering, the possibility to: (I) customize the shape and size of scaffolds, (II) develop highly mimicked tissues with a precise digital control, (III) manufacture complex structures and (IV) reduce the wastes related to the production process, are the main advantages of additive manufacturing technologies such as three-dimensional (3D) bioprinting. Specifically, this technique, which uses suitable hydrogel-based bioinks, enriched with cells and/or growth factors, has received significant consideration, especially in cartilage tissue engineering (CTE). In this field of interest, it may allow mimicking the complex native zonal hyaline cartilage organiza…
Titanium Lattice Structures Produced via Additive Manufacturing for a Bone Scaffold: A Review
2023
The progress in additive manufacturing has remarkably increased the application of lattice materials in the biomedical field for the fabrication of scaffolds used as bone substitutes. Ti6Al4V alloy is widely adopted for bone implant application as it combines both biological and mechanical properties. Recent breakthroughs in biomaterials and tissue engineering have allowed the regeneration of massive bone defects, which require external intervention to be bridged. However, the repair of such critical bone defects remains a challenge. The present review collected the most significant findings in the literature of the last ten years on Ti6Al4V porous scaffolds to provide a comprehensive summa…
Heritability of refractive astigmatism: a population-based twin study among 63- to 75-year-old female twins.
2013
PURPOSE: To examine the heritability of refractive astigmatism in older women. METHODS: Astigmatism was measured with an autorefractor in 88 monozygotic and 82 dizygotic female twin pairs aged 63 to 75 years. The prevalence and distribution of astigmatism and polar values J0 and J45 were estimated by standard statistical methods. Bivariate maximum likelihood model fitting was used to estimate genetic and environmental variance components using information from both eyes. RESULTS: Mean astigmatism of the more astigmatic eye was 0.93 diopters (D; SD ±0.58). Astigmatism of at least 0.25 D, 0.5 D, 0.75 D, or 1.0 D in either eye was present in 99.7%, 88.5%, 66.5%, and 46.2% of cases, respectivel…
Design of efficient codes for the AWGN channel based on decomposable binary lattices
1998
This work is concerned with the use of binary decomposable lattice codes over the QAM Gaussian channel. First, we investigate the structure of such class of lattices: we derive consistency conditions for the binary codes appearing in their decomposition and express their nominal coding gain and some bounds for their error coefficient in terms of the parameters of the component codes. Then we describe a general multistage bounded‐distance decoding algorithm with low complexity and we evaluate its performance. Finally, we develop a design example and report the corresponding simulation results; as a reference some comparisons with standard TCM codes are also presented.
A CNDO/2 study on the additivity and the nature of the non-additivity of the substituent effects on13C NMR shifts in chlorobenzenes and chlorophenols
1980
The general correlation between the electron densities and the 13C NMR chemical shifts is found to be quite poor in the cases discussed. The non-additivities of the substituent effects on the chemical shifts and the CNDO/2 electron densities correlate only weakly. However, when the electron densities are made specific to different types of atomic orbitals, the s electrons have a pronounced effect in all the models tested. This is explained by an indirect effect on the 〈1/r3〉 term of the p electrons. Good correlations are found between the sums of the chemical shifts and the corresponding sums of the substituent charge excesses. The different behaviour of OH and Cl substituents in the additi…
Influence of Material-Related Aspectsof Additive and Subtractive Ti-6Al-4VManufacturing on Energy Demandand Carbon Dioxide Emissions
2017
The additive manufacturing of metal parts represents a promising process that could beused alongside traditional manufacturing methods. The research scenario in this field isstill largely unexplored, as far as the technological solutions adopted to integrate differentprocesses are concerned and in terms of environmental and economic impact assessment.In this article, an electron beam melting (EBM) process and a machining process have beenanalyzed and compared using a cradle-to-grave life cycle–based approach. The productionof components made of the Ti-6Al-4V alloy has been assumed as a case study. Theproposed methodology is able to account for all of the main factors of influence on energydem…
Plant sterol oxides in functional beverages: Influence of matrix and storage
2014
Three plant sterol (PS)-enriched beverages, milk based fruit juice (MFJPS), fruit juice (FJPS) and milk beverage (MPS), were stored at 4, 24, or 37 °C and analysed at regular time intervals of 2 months until 6 months. PS stability was analysed from the production of phytosterol oxidation products (POPs). The β-sitosterol oxides (7α/7β-hydroxy, β/α-epoxy, triol, and 7-keto) and campesterol oxides (β/α-epoxy, and 7-keto) were detected in all beverages and at all storage times and temperatures. Total POP contents followed the order MPS≫FJPSMFJPS. In general, the beverages showed low PS oxidation levels (0.17%). Predictive models of POP content versus storage time were established. These models…