Search results for " Mill."

Luminescence properties of neodymium-doped yttrium aluminium garnet obtained by the co-precipitation method combined with the mechanical process.

2005

Nanopowders of yttrium aluminium garnet Y3Al5O12 (YAG) doped with neodymium ions were obtained by the co-precipitation method from the reaction of aluminium and yttrium nitrate and neodymium oxide with ammonia. After washing and drying the hydroxide precursors were calcined at 500, 700, 800 and 900 °C for 1 hour and at 1000 °C for 3 hours. This product was treated by ball milling in a zirconia vial for 0.5, 1.5 and 10 h in order to achieve smaller nanoparticles. The structure, microstructure, morphology and optical properties were investigated by means of diffractometric, microscopic and spectroscopic techniques. The course of the amorphous-to-crystalline transformation was complete after c…

Ball-milling and AlB2 addition effects on the hydrogen sorption properties of the CaH2 + MgB2 system

2011

Abstract Among the borohydrides proposed for solid state hydrogen storage, Ca(BH 4 ) 2 is particularly interesting because of its favourable thermodynamics and relatively cheap price. Composite systems, where other species are present in addition to the borohydride, show some advantages in hydrogen sorption properties with respect to the borohydrides alone, despite a reduction of the theoretical storage capacity. We have investigated the milling time influence on the sorption properties of the CaH 2  + MgB 2 system from which Ca(BH 4 ) 2 and MgH 2 can be synthesized by hydrogen absorption process. Manometric and calorimetric measurements showed better kinetics for long time milled samples. …

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representat…

2021

Background: hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods: we used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prev…

How to preserve and handle fish liver samples to conserve RNA integrity

2019

As transcriptomic studies are becoming more and more common, it is important to ensure that the RNA used in the analyses is of good quality. The RNA integrity may be compromised by storage temperature or freeze-thaw cycles, but these have not been well studied in poikilothermic fishes. This work studied the effects of tissue storage time and temperature, and freeze-thaw cycles of tissue and extracted RNA on RNA integrity in brown trout (Salmo trutta L.) liver. The storage time and temperature had an effect on RNA integrity, but RNA suitable for quantitative reverse transcription PCR (RT-qPCR) (RIN > 7) was still obtained from samples preserved at − 20 °C for 6 months. Freeze-thaw cycles of …

Dictamen de quatro medicos sobre la siembra de Arroces en la Huerta de la Ciudad de Valencia

Tít. obtingut de l'epígraf "Dictamen del Dr. Don Andres Piquer ... sobre la siembra de Arroces en la Huerta de la Ciudad de Valencia", 1751 Precedeix al tit: [creu graga Reclams

Don Thomas Vicente Tinagero, Secretario de su Magestad, y Escrivano mayor del Muy Ilustre Cabildo, y Regimiento de esta Muy Noble Magnifica, y Fiel C…

Precedeix al tít.: Banda xil Caplletra ornada Sign.: A[3 Reclams

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Precedeix al tit: [creu de Malta Com a tít. el començament del text

A sustainable phenolic compound extraction system from olive oil mill wastewater

2017

Abstract The reduction of environmental impact and the achievement of economic advantages based on by-product recovery is the aim of applying methodologies for phenolic compounds extraction from Olive Oil Mill Wastewater. Volume reduction of Olive Oil Mill Wastewater could generate important advantages in terms of waste disposal cost abatement and, in addition, reuse in the production of foods with health properties could lead to economic benefits. Despite the fact that literature shows that several techniques have been developed, few economic approaches have been presented. This paper assesses the economic feasibility of a system based on membrane filtration and reverse osmosis processes f…

Correlation between milling parameters and microstructure characteristics of nanocrystalline copper powder prepared via a high energy planetary ball …

2007

The microstructure evolution of Cu-nanostructured powders versus the ball milling conditions was investigated by whole peak profile powder pattern modeling method. This method allows defining in some approach the characteristics of as-milled Cu powder microstructure in terms of crystallite size, type and density of dislocations and twin faults density. It is shown that the change of microstructure characteristics of as-milled Cu powder versus the ball milling conditions (under constant time of the ball milling) depend on only some energy parameters of the milling, for example, average size of crystallite is uniquely defined by energy of the shock, whereas the portion of edge and screw compo…

Effect of Ni content on the structure and hydrogenation property of mechanically alloyed TiMgNix ternary alloys

2017

Abstract In this study, TiMgNix samples (x = 0.2, 0.4, 0.6, 0.8, 1) have been prepared by mechanical alloying using a planetary high-energy ball mill. The structural transformations were characterized by XRD and indicated that all the as-milled TiMgNix alloys consist of mixtures of crystalline Mg and amorphous Ti-Ni-(Mg) phase. TEM analyses also show that nanocrystallites and amorphous phases coexist in the as-milled TiMgNi alloy. Electrochemical test shows that the TiMgNi composition yields the highest discharge capacity. The discharge capacities and activation properties of TiMgNix alloys linearly increase with increasing Ni content. The MgTiNi0.8 composition boasts the best cycling prope…