2,388 research outputs found
Arsenic removal from Pinctada martensii enzymatic hydrolysate by using Zr(IV)-loaded chelating resin
No full textThe present study investigated the removal of inorganic arsenic from Pinctada martensii enzymatic hydrolysate through unmodified resin (D296) and Zr(IV)-loaded chelating resin (Zr-D401). By loading Zr to macroporous chelating resin D401, the as exchange adsorption active sites are generated. This transforms D401 from a material that does not have the arsenic adsorption capacity into a material that has excellent arsenic exchange adsorption capacity. The static adsorption experiments were conducted to investigate the optimal removal condition for D296 and Zr-D401. The experimental results show that: the optimum condition for D296 is that T= 25A degrees C, pH = 5, resin additive amount = 1 g (50 mL)(-1), and contact time = 10 h, the corresponding arsenic removal rate being 65.7%, and protein loss being 2.33%; the optimum condition for Zr-D401 is that T=25A degrees C, pH = 8, resin additive amount = 1 g (50 mL)(-1), and contact time=10 h, the corresponding arsenic removal rate being 70.3%, and protein loss being 4.65%. These results show that both of the two resins are effective in arsenic removal for preserving useful substance. Our research provides scientific evidence and advances in the processing technology for heavy metal removal in shellfish.The present study investigated the removal of inorganic arsenic from Pinctada martensii enzymatic hydrolysate through unmodified resin (D296) and Zr(IV)-loaded chelating resin (Zr-D401). By loading Zr to macroporous chelating resin D401, the as exchange adsorption active sites are generated. This transforms D401 from a material that does not have the arsenic adsorption capacity into a material that has excellent arsenic exchange adsorption capacity. The static adsorption experiments were conducted to investigate the optimal removal condition for D296 and Zr-D401. The experimental results show that: the optimum condition for D296 is that T= 25A degrees C, pH = 5, resin additive amount = 1 g (50 mL)(-1), and contact time = 10 h, the corresponding arsenic removal rate being 65.7%, and protein loss being 2.33%; the optimum condition for Zr-D401 is that T=25A degrees C, pH = 8, resin additive amount = 1 g (50 mL)(-1), and contact time=10 h, the corresponding arsenic removal rate being 70.3%, and protein loss being 4.65%. These results show that both of the two resins are effective in arsenic removal for preserving useful substance. Our research provides scientific evidence and advances in the processing technology for heavy metal removal in shellfish
Supplementary information files for "Recommended solutions for the disinfection of Ti-Zr-cu-pd bulk metallic glasses"
No full textSupplementary files for article "Recommended solutions for the disinfection of Ti-Zr-cu-pd bulk metallic glasses"Disinfection of medical devices is crucial to patient safety. Notably, an incorrect selection of disinfectant can damage the material surface and impact its performance. Ti-Zr-Cu-Pd bulk metallic glasses (BMGs) show considerable potential for biomedical use, however standard sterilisation protocols remain undeveloped. This study evaluates the effects of common clinical disinfection solutions, including NaOH, NaClO, and Virkon®, on Ti-Zr-Cu-Pd BMGs, to assess their impact on surface characteristics (chemical composition, surface free energy) and on biocompatibility (pre-osteoblast cells behaviour). The findings aim to inform practical guidelines for safe and effective cleaning and sterilisation of devices that contain these alloys.© The Author(s), CC BY 4.0</p
Mechanical performance and fracture behavior of Fe₄₁Co₇Cr₁₅Mo₁₄Y₂C₁₅B₆ bulk metallic glass
No full textThe mechanical properties of a new Fe₄₁Co₇Cr₁₅Mo₁₄Y₂C₁₅B₆ bulk glassy alloy were studied by impact bending, compression, and hardness tests carried out at room temperature. The compressive fracture strength, elastic strain to fracture, Young’s modulus and Vickers hardness were measured to be 3.5 GPa, 1.5%, 265 GPa, and 1253 kg mm⁻², respectively. The fracture mode of the glassy alloy under uniaxial compression is different from those of other bulk metallic glasses in that this fracture mode causes the samples to be broken, in an exploding manner, into a large number of micrometer-scale pieces. The fracture mechanisms of this bulk glassy alloy under bending and uniaxial compression are discussed based on the observation of the fracture surfaces. Vickers indentation tests indicate that the structure of the glassy ingot may be inhomogeneous
Microstructure of Zr-alloyed coating using pulsed laser
No full textCoatings were synthesized by laser alloying of zirconium (Zr) particles using a pulsed Nd:YAG laser on an austenite stainless steel. The distribution of Zr is uneven, in a depth of 18 mum just below the surface of the pool. The coating consisted of duplex microstructures, i.e. metallic glass (MG) and austenite. The MG formed in Zr-contained regions, with the Zr composition ranging from 7.6 to 16.8 at.%. The formation of the MG was attributed to an increase in glass-forming ability by Zr addition
Behavior and Impact of Zirconium in the Soil–Plant System: Plant Uptake and Phytotoxicity
No full textBecause of the large number of sites they pollute, toxic metals that contaminate terrestrial ecosystems are increasingly of environmental and sanitary concern (Uzu et al. 2010, 2011; Shahid et al. 2011a, b, 2012a). Among such metals is zirconium (Zr), which has the atomic number 40 and is a transition metal that resembles titanium in physical and chemical properties (Zaccone et al. 2008). Zr is widely used in many chemical industry processes and in nuclear reactors (Sandoval et al. 2011; Kamal et al. 2011), owing to its useful properties like hardness, corrosion-resistance and permeable to neutrons (Mushtaq 2012). Hence, the recent increased use of Zr by industry, and the occurrence of the Chernobyl and Fukashima catastrophe have enhanced environmental levels in soil and waters (Yirchenko and Agapkina 1993; Mosulishvili et al. 1994 ; Kruglov et al. 1996)
The correlation between weakest configurations and yield strength of Zr-based metallic glasses
No full textA direct relationship between the yield strength and the atomic ratio of solvent (Zr) atoms in the Zr-Cu-Al-Ni metallic glasses system is firstly uncovered. It is found that either shear modulus or yield strength decreases almost nearly with the increase in atomic ratio of Zr. The origin of this relationship is ascribed to the preferential straining of the weakest configurations which consist of the solvent-solvent bonds and the free volume concentrated in them. It is suggested that a higher atomic ratio of Zr corresponds to a larger amount of weakest configurations which will facilitate the activation and the accumulation of the shear transformations and finally results in the lower yield strength. This finding may provide an effective strategy for designing high-strength metallic glasses by modifying the chemical composition
Enhanced Plasticity of Zr-Based Bulk Metallic Glass Matrix Composite with Ductile Reinforcement
No full textA composite material containing uniformly distributed micrometer-sized Nb particles in a Zr-based amorphous matrix was prepared by suction cast. The resulting material exhibits high fractured strength over 1550 MPa and enhanced plastic strain of about 29.7% before failure in uniaxial compression test at room temperature. Studies of the serrations on the stress-strain curves and the shear bands on the fractured samples reveal that the amplitude of the stress drop of each serration step corresponds to the extent of the propagation of a single shear band through the materials. The composite exhibits more serration steps and smaller amplitude of stress drop due to the pinning of shear band propagation by ductile Nb particles
Effects of crystallinity and impurities on the electrical conductivity of Li-La-Zr-O thin films
No full textWe present a study of the fabrication of thin films from a Li7La3Zr2O12 (LLZO) target using
pulsed laser deposition. The effects of substrate temperatures and impurities on
electrochemical properties of the films were investigated. The thin films of Li-La-Zr-O
were deposited at room temperature and higher temperatures on a variety of substrates.
Deposition above 600 °C resulted in a mixture of cubic and tetragonal phases of LLZO, as
well as a La2Zr2O7 impurity, and resulted in aluminum enrichment at the surface when Al-
containing substrates were used. Films deposited at 600 °C exhibited the highest room
temperature conductivity, 1.61×10-6 S/cm. The chemical stability toward metallic lithium
was also studied using X-ray photoelectron spectroscopy, which showed that the oxidation
state of zirconium remained at +4 following physical contact with heated lithium metal
Penny-shaped crack propagation in spallation of Zr-BMGs
No full textTypical penny-shaped microcracks at their propagating in spallation of Zr-based bulk metallic glass (Zr-BMG) samples were captured by a specially designed plate impact technique. Based on the morphology and stress environment of the microcrack, a damaged zone or propagation zone around the crack tips, similar to the cohesive zone in classical fracture theories, is applied. Especially the scale of such a damaged zone represents a scale of the crack propagation. Its fast propagation would quickly bring a longer crack or cause cracks coalesce to form another longer one. The estimated propagation scales of microcracks are reasonable compared with what occurred in the Zr-BMG samples
The influence of a Zr-based conversion treatment on interfacial bonding strength and stability of epoxy coated carbon steel
No full textThe effect of a zirconium (Zr)-based pretreatment on interfacial bonding properties of a fusion bonded epoxy (FBE) coating on carbon steel is investigated. The initiation and kinetics of delamination of epoxy coatings applied on differently pretreated carbon steel surfaces is studied with scanning Kelvin probe (SKP). In-situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) is applied to study interfacial coating-oxide chemistry changes upon electrolyte diffusion towards the buried interface. Corresponding coating degradation is analyzed with the use of electrochemical impedance spectroscopy (EIS). pull off experiments showed a clear beneficial effect of the Zr-based pretreatment improving the dry and wet adhesion properties of the fusion bonded epoxy coating to the carbon steel surface particularly upon exposure to wet and corrosive conditions. This increase in interfacial bonding stability is confirmed by the ATR-FTIR and EIS experiments and delayed and slower delamination was observed in the SKP measurements.Accepted Author Manuscript(OLD) MSE-6(OLD) MSE-
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