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101.
Natural materials are becoming a valid alternative to traditional synthetic ones for sound absorption applications. In this paper, the acoustic properties of broom fibers are reported and discussed. Broom plants grow up on hills and mountains and are common in many Mediterranean countries. The materials were cut and shredded to prepare several samples. Test specimens made of broom pieces with a diameter from 1.5 mm to 4 mm were prepared. The normal sound absorption for samples with a thickness of 60 mm, 80 mm and 120 mm was then measured. Results are particularly promising especially above 500 Hz, as the samples consistently reported a normal sound absorption above 0.5. The increase in the sample thickness allowed to obtain higher sound absorption at lower frequencies, as generally expected for porous materials. The main limit of the investigated samples was the appearance of sound absorption resonances. These were more evident for the samples composed of pieces with larger diameter, and may be attributed to the loose nature of the tested samples.  相似文献   
102.
0.3%C–CrMoV steel were processed through electric arc furnace melting followed by electro slag refining. 2800 mm diameter class of rolled rings and 8 mm thick plates required for fabrication of solid rocket booster motorcase were realized. Tensile and fracture toughness properties were evaluated as a part of characterization of the steel. Low fracture toughness in initial melts was investigated using optical and scanning electron microscopy. Modifications in methods of alloying additions/processing were suggested and incorporated to achieve the desired mechanical properties in industrial scale melts. Process was also fine-tuned by incorporating additional thermomechanical working and heat treatment cycles to achieve the required mechanical properties. Hardening cycle of 925 °C for 1 h followed by oil quenching and tempering cycle of 505 °C for 2 h followed by oil quenching was found to result in optimum combination of mechanical properties. Repeatability in processing and consistency in achieving the mechanical properties of the steel at industrial scale was demonstrated by processing 24 melts of 6 tons each into large size rings and plates.  相似文献   
103.
Different methodologies are used for modelling flow-like landslides. A common critical point concerns the flooding into town areas, which cannot be assimilated straight to a morphology, especially, when the urban tissue is very irregular with narrow streets and odd setting of buildings, so that discretization processes of approximating numerical methods have to be carefully examined in their limits. A semi-empirical approach by the computational paradigm of cellular automata is here considered with SCIDDICA, a competitive (related to PDE approach) cellular automata model for 3-dimensions simulation of flow-like landslides. This paper presents innovations to the transition function of SCIDDICA-SS2, which manage opportunely building data in the cells corresponding to the urban tissue. The novelties of the transition function need a theorem, here demonstrated which regards the Algorithm of Minimization of Differences in the new context of inhomogeneous cells. This progress permits to simulate the complete evolution of landslides, from the detachment area to its exhaustion almost on the same precision level. This is an advantage for hazard and risk analyses in threatened zones. Improved SCIDDICA-SS2 was applied successfully to all the well-known 2009 debris flows of Giampilieri Superiore (Sicily) also in comparison with simulation results of the previous versions.  相似文献   
104.
The conjugation of drugs with nanoparticles represents an innovative approach for controlled and targeted administration of therapeutic agents. Nanoparticle-based systems have been tested for the inner ear therapy, increasing the drug diffusion and being detected in all parts of the cochlea when locally applied near the round window. In this study, glycerol monooleate liquid crystalline NanoParticles were conjugated with Dexamethasone (NPD), a hydrophobic drug already used for inner ear treatments but defective in solubility and bioavailability. NPD has been tested in vitro in the cell line OC-k3, a model of sensory cells of the inner ear, and the therapeutic efficacy has been evaluated against cisplatin, a chemotherapeutic compound known to induce ototoxicity. After comparing the physical chemical characteristics of NPD to the equivalent naïve nanoparticles, an initial investigation was carried out into the nanoparticle’s uptake in OC-k3 cells, which takes place within a few hours of treatment without causing toxic damage up to a concentration of 50 µg/mL. The NPD delivered the dexamethasone inside the cells at a significantly increased rate compared to the equivalent free drug administration, increasing the half-life of the therapeutic compound within the cell. Concerning the co-treatment with cisplatin, the NPD significantly lowered the cisplatin cytotoxicity after 48 h of administration, preventing cell apoptosis. To confirm this result, also cell morphology, cell cycle and glucocorticoids receptor expression were investigated. In conclusion, the NPD system has thus preliminarily shown the potential to improve the therapeutic efficacy of treatments delivered in the inner ear and prevent drug-induced ototoxicity.  相似文献   
105.
Journal of Superconductivity and Novel Magnetism - It is now recognized that high-temperature superconducting (HTS) technology has a significant potential for future magnetic levitation (Maglev)...  相似文献   
106.
The antioxidant properties of some single components and the total antioxidant activity of extra‐virgin olive oil have been evaluated by the oxygen radical absorbance capacity (ORAC) method. The total ORAC of the extra‐virgin olive oil was found to be positively correlated with the concentration of total polyphenols, which are important to the shelf life of the product. Among the single phenolic compounds studied, gallic acid showed a higher ORAC than caffeic acid and oleuropein, while among the derivates of oleuropein, hydroxytyrosol was found to be the most active compound among all the phenols studied. The total ORAC of commercial olive oils differed according to the concentration of total polyphenols. The total ORAC of extra‐virgin olive oil was constant during 1 year of storage in rational conditions, whereas it worsened dramatically in olive oil damaged by the lipase‐producing yeast Williopsis californica or by lipase from Pseudomonas spp. The study accomplished on the oily fraction of the fruits before harvesting demonstrated that the total ORAC of the oil of under‐ripe green olives is higher compared to that shown by mature fruits; therefore, through the choice of the harvesting time, it is possible to define also the future content of polyphenols of the oil. The total ORAC test, together with other analyses, can be considered as a qualitative parameter that can contribute to the expression of technological and health virtues of extra‐virgin olive oil.  相似文献   
107.
Colloidal Er(3+)/Yb(3+), Tm(3+)/Yb(3+) and Ho(3+)/Yb(3+) doped CaF(2) nanoparticles have been prepared by a one-pot hydrothermal procedure and their upconversion properties have been investigated.  相似文献   
108.
The metabolic affects of anapriline, captopril, and clophelin were studied in the blood and liver homogenates ex vivo and in vitro in experiments on intact rats and rats with alloxan diabetes. Anapriline lowered the blood lactate content in rats with diabetes and intact rats, reduced the level of glycemia in animals with marked hyperglycemia. Captopril increased the blood insulin and lactate content in rats with diabetes and the content of pyruvate in vivo. The results of the study show that the use of clophelin and anaprilin in the treatment of patients with diabetes mellitus is most rational.  相似文献   
109.
In this paper, we introduce a new demand probabilistic approach, named M.DPA.eoq (Montanari Demand Probabilistic Approach in economic order quantity [EOQ] scenario), for predicting the demand seen by an upper tier echelon (e.g. a distribution centre) of a supply network, serving several lower tier echelons operating according to an EOQ reorder policy. The M.DPA.eoq is based on an analytic approach, by which we derive the distribution of the demand seen by the upper tier echelon of the supply network. The approach has been designed to be very simple, so as to gain in pedagogical value. The simplicity and ease of application of this approach are confirmed by the possibility of exploiting general purpose software, such as Microsoft ExcelTM, to implement and validate it. Moreover, the M.DPA.eoq has potential to be directly exploited by practitioners, such as supply network managers, to estimate the distribution of the demand the upper tier echelon will face under a defined network structure. Students and researchers could also benefit from such a model, given its ease of understanding and usage. With the purpose of showing its potential usefulness in real cases, we discuss two practical implications of the M.DPA.eoq, referring to the use of its results for: (1) computing the bullwhip effect of the network; and (2) analysing the impact of each retail store on the variance of the demand seen by the upper tier echelon.  相似文献   
110.
Automatic provisioning and recovery of lightpaths with selectable traffic engineering policies are considered basic features of near future optical transport networks (OTN). Worldwide researchers recognize generalized multi-protocol label switching (GMPLS) architecture as the viable control plane solution to achieve these issues in OTN. Growing effort is ongoing to find new recovery models for handling failure conditions in the networks, trying to set up alternative strategies to classical heavy-cost SDH/SONET protection techniques. In this paper, a pre-planned local repair recovery strategy is described. Allocation of primary paths is provided using the interference concept, in order to set a threshold between resources dedicated to working paths and those allocable for local backups in case of failure. Tests of the strategy are shown for a sample national optical transport network, aimed at valuing local-repair recovery times at different failure location and seriousness.  相似文献   
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