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Solid solutions of ZryTi1−yS2 (y = 0.1, 0.2) compositions have been synthesized. The electrochemical introduction of lithium is carried out by the galvanostatic intermittent titration technique. An isothermal section of the phase diagram of the LixZryTi1−yS2 system at room temperature has been constructed. The limiting solubility of lithium in solid solutions decreases with an increasing amount of titanium substituted for zirconium. It was noted that at low lithium concentrations (x < 1), there is no change in the E(x) dependence when titanium is replaced by zirconium. This may indicate the formation of separate TiS2 and ZrS2 layers. [ABSTRACT FROM AUTHOR]

PurposeMultiple myeloma is a plasma cell malignancy with an unmet clinical need for improved imaging methods and therapeutics. Recently, we identified CD46 as an overexpressed therapeutic target in multiple myeloma and developed the antibody YS5, which targets a cancer-specific epitope on this protein. We further developed the CD46-targeting PET probe [89Zr]Zr-DFO-YS5 for imaging and [225Ac]Ac-DOTA-YS5 for radiopharmaceutical therapy of prostate cancer. These prior studies suggested the feasibility of the CD46 antigen as a theranostic target in multiple myeloma. Herein, we validate [89Zr]Zr-DFO-YS5 for immunoPET imaging and [225Ac]Ac-DOTA-YS5 for radiopharmaceutical therapy of multiple myeloma in murine models.Experimental designIn vitro saturation binding was performed using the CD46 expressing MM.1S multiple myeloma cell line. ImmunoPET imaging using [89Zr]Zr-DFO-YS5 was performed in immunodeficient (NSG) mice bearing subcutaneous and systemic multiple myeloma xenografts. For radioligand therapy, [225Ac]Ac-DOTA-YS5 was prepared, and both dose escalation and fractionated dose treatment studies were performed in mice bearing MM1.S-Luc systemic xenografts. Tumor burden was analyzed using BLI, and body weight and overall survival were recorded to assess antitumor effect and toxicity.Results[89Zr]Zr-DFO-YS5 demonstrated high affinity for CD46 expressing MM.1S multiple myeloma cells (Kd = 16.3 nmol/L). In vitro assays in multiple myeloma cell lines demonstrated high binding, and bioinformatics analysis of human multiple myeloma samples revealed high CD46 expression. [89Zr]Zr-DFO-YS5 PET/CT specifically detected multiple myeloma lesions in a variety of models, with low uptake in controls, including CD46 knockout (KO) mice or multiple myeloma mice using a nontargeted antibody. In the MM.1S systemic model, localization of uptake on PET imaging correlated well with the luciferase expression from tumor cells. A treatment study using [225Ac]Ac-DOTA-YS5 in the MM.1S systemic model demonstrated a clear tumor volume and survival benefit in the treated groups.ConclusionsOur study showed that the CD46-targeted probe [89Zr]Zr-DFO-YS5 can successfully image CD46-expressing multiple myeloma xenografts in murine models, and [225Ac]Ac-DOTA-YS5 can effectively inhibit the growth of multiple myeloma. These results demonstrate that CD46 is a promising theranostic target for multiple myeloma, with the potential for clinical translation.

The epitaxial growth of boron rich hexagonal zirconium diborides (h-ZrB2+δ) thin films on Si(111) substrates using the magnetron co-sputtering technique with elemental zirconium and boron is reported. The effect of process temperature (700–900 °C) on the compositions and epitaxy quality was investigated. The chemical composition of the films was found to have a higher boron to zirconium ratio than the ideal stoichiometric AlB2-type ZrB2 and was observed to be sensitive to process temperature. Films deposited at 700 °C exhibited intense diffraction peaks along the growth direction corresponding to (000ℓ) of h-ZrB2 using both lab and synchrotron-based x-ray diffractograms. The thermal and compositional stability of the epitaxial h-ZrB2+δ film was further evaluated under a nitrogen-rich environment through isothermal annealing which showed a reduction in in-plane misorientation during thermal annealing. The relative stability of deviating compositions and the energetics of impurity incorporations were analyzed using density functional theory simulations, and the formation of native point defects or impurity incorporation in h-ZrB2 was found to be endothermic processes. Our experimental results showed that an epitaxial thin film of h-ZrB2+δ can be grown on Si(111) substrate using a magnetron co-sputtering technique at a relatively low processing temperature (700 °C) and has the potential to be used as a template for III-nitride growth on Si substrates. [ABSTRACT FROM AUTHOR]

A heterogeneous zirconium catalyst was grafted on a ceria‐coated silica support, denoted as Zr(OEt)x/CeO2/SiO2. It exhibited higher catalytic activity compared to its homogeneous counterpart, Zr(OEt)4, in the conversion of carbon dioxide to diethyl carbonate using tetraethyl orthosilicate as a regenerable agent in the absence of any dehydrating agents under non‐protic conditions. We found that the ceria‐coated silica (CeO2/SiO2) support not only improved the catalytic activity of Zr(OEt)4 but also inhibited catalyst deactivation during catalyst recycling tests. Furthermore, we analyzed the surface of the Zr(OEt)x/CeO2/SiO2 catalysts by FE‐SEM and EDX. [ABSTRACT FROM AUTHOR]

A zirconocene dichloride‐catalyzed alkene hydrosilylation is reported that can be applied to non‐activated and conjugated terminal and internal alkenes. It involves a catalytic Zr‐walk process and leads to a selective conversion to the linear product. Lithium methoxide serves as mild catalyst activating agent, which significantly increases the applicability and operational simplicity in comparison to earlier zirconium(II)‐based protocols. Supported by additional experiments and calculations, a mechanism via zirconium(IV) intermediates is proposed. Due to the benign nature and ready‐availability of the zirconium catalyst, the reaction is an attractive alternative to established alkene hydrosilylation methods. [ABSTRACT FROM AUTHOR]

New anodes consisting of zirconium-doped PbO2 coating, growth on titanium dioxide interlayer, were deposited on titanium substrates using spin coating method and have been tested for the removal of ampicillin, a β-lactam antibiotic, from water. Morphological, structural, and electrochemical properties of the prepared coatings were characterized by scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), and electrochemical impendence spectroscopy (EIS). Results showed that the incorporation of zirconium dopant had a noticeable modification in the morphology of anodes. An increase in the surface roughness and the specific active area were observed with Ti/TiO2/PbO2- 10% Zr electrode compared to other anodes. The electrochemical measurements indicated that the anode doped with 10% Zr showed a more protective coating performance than the undoped and 20% Zr-doped PbO2 electrodes. The experiments on ampicillin degradation revealed that doped lead dioxide anodes have excellent electrocatalytic activity. The major byproduct generated during anodic oxidation treatment has been identified as ampicilloic acid by liquid chromatography-mass spectroscopy (LC–MS) analysis. Results demonstrated that Ti/TiO2/PbO2- 10% Zr anode presents the best removal rate of ampicillin with a minimum intermediate amount, which leads to conclude that 10% is the optimum percentage of zirconium dopant for antibiotic wastewater treatment. [ABSTRACT FROM AUTHOR]

The results of modeling and research of casting, rolling, and extrusion processes for producing wire from AleZr system alloys and determining its physical and mechanical properties have been presented. When implementing combined processes for processing aluminum alloys, the number of operations is significantly reduced, productivity and yield are increased. As a result of the conducted research, the influence of alloy preparation modes and their chemical composition on the physical, mechanical and electrical properties of longish semifinished products from AleZr system alloys obtained by combined rollingextrusion (CRE) and ingotless rolling-extrusion (IRE) methods were investigated. The simulation of the CRE process for one of these alloys of the system was carried out in the DEFORM 3D software package using data on its rheological properties obtained by the hot torsion method. Based on the modeling results, the optimal modes for conducting experimental studies were selected. The features of metal forming were experimentally studied, the temperature-velocity and technological parameters of combined processing were found, as well as the properties of cast billets, including those obtained using an electromagnetic mold (EMM). The results of experimental studies of the CRE and IRE processes suggest that it is possible to obtain longish deformed semifinished products from alloys AleZr system with a level of physical, mechanical and electrical properties that meet international standards. At all technological stages, including drawing, the structure of the metal was studied, and data on the physical and mechanical properties of hot-extruded rods and wire in cold-deformed and annealed states was obtained. The heat resistance of wire made from the investigated alloys was studied and it was found that after testing at a temperature of 280 °C and a holding time of 1 h, it satisfies the requirements of the AT3 type standard with a maximum permissible long-term operating temperature of 210 °C. Recommendations are given for industrial implementation; alloys containing 0.15e0.20% zirconium and 0.10e0.15% iron are recommended for the manufacture of AT1 type wire without heat treatment, as well as 0.25e0.30% Zr and 0.2e0.25% Fe for AT3 wire type with heat treatment. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the influence of multiplanar reconstruction thickness on the detection of peri‐implant bone defects with a standalone zirconia implant and compare it to when another implant is in the vicinity using cone‐beam computed tomography (CBCT). Materials and Methods: Five dry human mandibles were used to create twenty implant sites in the second premolar and first molar regions. The OP300 Maxio was used to acquire CBCT images (90 kVp, 6.3 mA, 5 × 5 cm FOV, and 0.125 mm3 voxel size) before and after creating 3 mm peri‐implant bone defects in the buccal aspect of the premolar region. Half of the scans featured a single zirconia implant in the premolar region, while the others had two implants in the premolar and molar regions. Three reconstruction thicknesses (0.125 mm, 1 mm, and 2 mm) were considered for the multiplanar reconstruction analyses. Five oral and maxillofacial radiologists assessed the detection of peri‐implant bone defects using a 5‐point scale. Diagnostic parameters were calculated and compared using Two‐way ANOVA (α =.05). Results: The studied factors showed no significant influence on the diagnosis of peri‐implant bone defects (p >.05). Diagnostic performance was notably higher with a single implant, especially with a 2‐mm reconstruction thickness (AUC = 0.88, sensitivity = 0.68, specificity = 0.94). Although the differences were not statistically significant, the results were more modest when two implants were present (AUC = 0.80, sensitivity = 0.58, specificity = 0.82). Conclusions: The presence of an adjacent zirconia implant and variations in reconstruction thickness did not influence the detection of 3 mm buccal peri‐implant bone defects on CBCT images. [ABSTRACT FROM AUTHOR]

A method of 90Sr determination in natural waters was tested in this study. The method included the steps of strontium preconcentration by a carbonate-containing zirconium hydroxide (Termoxid-3 K), strontium stripping with 1 M HCl and preparation of a counting source, followed by its measurement using a low background alpha/beta radiometer UMF-2000. Using the described method, we have determined activity concentrations of 90Sr in 16 samples of natural water collected at the territories of Sverdlovsk region and Chelyabinsk region (Middle Urals, Russia) as well as 8 samples from observing wells at a radioactive waste storage facility and 3 samples from observing wells at a point of radioactive waste final disposal. The dependence of strontium chemical yield in the method on calcium concentration and water hardness was determined. It was shown that strontium chemical yield was constant (81 ± 2%) for natural waters with a hardness less than 5.2 mmol/L and calcium concentration less than 76 mg/L; thus, a control of strontium chemical yield is not necessary for such water samples. A decrease of strontium chemical yield to 66.5 ± 1.5% was observed at higher calcium concentrations up to 178 mg/L. The method provided a minimum detectable activity of 90Sr as low as 0.02 Bq/L. [ABSTRACT FROM AUTHOR]

A radiochemical procedure has been developed for the quantification of uranium and thorium isotopes in NORM samples from the ceramic industry, such as zirconium sands, zirconium flours, micronized zircon, pigments and personal aerosol filters. The method is based on a fusion pretreatment with borate salts, a separation with anion exchange resins and alpha-particle spectrometry measurement. This method is an alternative to gamma spectrometry when the amount of sample is extremely small (2–10 mg) as in the case of aerosol filters, or there is no secular equilibrium in the 238U and 232Th chains, as in the ceramic pigments. The method has been validated with different ceramic materials and the comparison of the results with gamma measurements. Its reproducibility was also checked with different sample masses. [ABSTRACT FROM AUTHOR]

Removing contaminated Arsenazo III dye from contaminated effluent is a challenge and of great interest due to its hazard and environmental impact. Therefore, the biggest challenge was producing highly efficient, easy to recycle, and economically inexpensive adsorbent materials for the contaminated dye. Three chemically stable zirconium nanocomposites with unique properties were synthesized by gel-precipitation technology. The composition, chemical, and physical properties of zirconium molybdate, tungstate, and silicate nanocomposites have been extensively proven using many different and appropriate devices such as XRD, SEM–EDX, TEM, FT-IR, BET, DLS, TGA-DTA, and zeta potential. By utilizing the most effective adsorption techniques, Azo-dye was successfully bound to ZrMo-NPs, ZrW-NPs, and ZrSi-NPs composites. The uptake capacities for these composites were measured at 0.29, 0.79, and 1.61 mmol.g−1, respectively. The sorption parameters were optimized as follows: a feed solution pH of 3 for ZrMo-NPs, a pH of 2.3 for ZrW-NPs, and a pH of 2.3 for ZrSi-NPs. The stirring time was set at 30 min, the metal ion concentration was 1.64 mmol L−1, and the sorbent dose was 7.5 mg. The adsorption results agreed well with the Langmuir isotherm and the pseudo-second-order reaction models and demonstrated the endothermic nature and kinetic improvement by increasing temperatures. The three nanocomposites effectively eliminated tainted dye from lab wastewater, offering promise for their potential applications in the future. [ABSTRACT FROM AUTHOR]

Nanoscale molecular materials have emerged as a new class of compounds at the nanometer scale with well‐defined chemical structures, remarkable uniformity and high reproducibility. Among these materials, zirconium‐based metal‐organic cages (MOCs) have attracted significant attention due to their exceptional stability and applications in catalysis, recognition and separation and so on. However, their poor water solubility impedes their biomedical applications. In this study, decorating the ligand with Ru(II) complexes can not only improve the water solubility but also endow bright red fluorescence with large Stokes shift (180 nm). Notably, butyl‐modification of the cyclopentadiene rings can significantly enhance the cell uptake (100 folds) of nanocages via actin‐ and dynamin‐mediated endocytosis. The unique advantages and easy modifiability of these nanocages make them highly promising candidates for diverse biological applications. [ABSTRACT FROM AUTHOR]

The mutual influence of interface processes during simultaneous contact of zirconia ceramic plate with adhesion-active Cu–Ga–Ti melt (on one side of the plate) and inert to oxides liquid copper (on other side of the plate) was studied. Wetting of ceramic with metal melts was studied by sessile drop method, the structure of the interfaces was determined using SEM. Due to the dissolution of ceramic oxygen in Cu–Ga–Ti, non-stoichiometric zirconia (ZrO2-x) is formed, then ‘surplus’ zirconium from the ZrO2-x structure dissolves in the copper melt, the stoichiometry of zirconia is restored and an additional amount of oxygen dissolves in the Cu–Ga–Ti melt. It leads to a decrease in the adhesion of Cu–Ga–Ti to ceramics, while improving the wetting of ZrO2 ceramics with copper. The ZrO2–Cu–Ga–Ti interface contains copper–titanium–oxygen intermetallides with zirconia inclusions, which does not provide adhesion of metals with solid oxides. If the contact of Cu–Ga–Ti with ZrO2 is formed before contact with liquid copper, then the interface layer contains oxidized titanium, which promotes adhesion of metal to ceramic. Thus, the design of the sample affects the processes in the studied systems in the same way as the heating mode and the amount of the active component. [ABSTRACT FROM AUTHOR]

The amorphous materials of the Ti45Zr38Ni17 composition synthesized by mechanical alloying are widely recognized for their ability to store hydrogen with gravimetric densities above 2 wt.%. It is also known that those alloys can form a quasicrystalline state after thermal treatment and their structural and hydrogen sorption properties can be altered by doping with various elements. Therefore, in this paper, the results of the studies on the Ti45Zr38Ni17 system with yttrium substituted for titanium and zirconium are presented. We demonstrate that these alloys are able to absorb hydrogen with a concentration of up to 2.7 wt.% while retaining their amorphous structure and they transform into the unique glassy-quasicrystal phase upon annealing. Furthermore, we demonstrate that the in-situ hydrogenation of those new materials is an effortless procedure in which the decomposition of the alloy can be avoided. Moreover, we prove that, in that process, hydrogen does not bind to any specific component of the alloy, which would otherwise cause the formation of simple hydrides or nanoclusters. [ABSTRACT FROM AUTHOR]

In the field of industrial semi‐hydrogenation of trace alkynes amidst alkene feedstocks, the pivotal challenge lies in circumventing the hydrogenation of alkenes. Herein, we present Zr(OH)4 as an innovative catalyst for the semi‐hydrogenation of phenylacetylene, demonstrating remarkable selectivity towards styrene (>96 %), while exhibiting inactivity towards free styrene. Notably, Zr(OH)4 achieves a 95 % conversion of quasi‐industry 1 mol % phenylacetylene within styrene, with a mere 0.44 % styrene loss. Experimental and theoretical results confirm both terminal Zr−O−H and bridge Zr−O−H can dissociate H2, while the terminal Zr−O−H plays a crucial role on activating phenylacetylene through the sequential hydrogenation process of C6H5C≡CH→C6H5C=CH2→C6H5CH=CH2. The high rate of phenylacetylene removal is attributed to its strong adsorption capacity, while Zr(OH)4 has a significantly weaker adsorption capacity for styrene. [ABSTRACT FROM AUTHOR]

Immuno-positron emission tomography (immunoPET) enables imaging of specific targets that play a role in targeted therapy and immunotherapy, such as antigens on cell membranes, targets in the disease microenvironment, or immune cells. The most common immunoPET applications use a monoclonal antibody labeled with a relatively long-lived positron emitter such as 89Zr (T1/2 = 78.4 h), but smaller antibody-based constructs labeled with various other positron emitting radionuclides are also being investigated. This molecular imaging technique can thus guide the development of new drugs and may have a pivotal role in selecting patients for a particular therapy. In early phase immunoPET trials, multiple imaging time points are used to examine the time-dependent biodistribution and to determine the optimal imaging time point, which may be several days after tracer injection due to the slow kinetics of larger molecules. Once this has been established, usually only one static scan is performed and semi-quantitative values are reported. However, total PET uptake of a tracer is the sum of specific and nonspecific uptake. In addition, uptake may be affected by other factors such as perfusion, pre-/co-administration of the unlabeled molecule, and the treatment schedule. This article reviews imaging methodologies used in immunoPET studies and is divided into two parts. The first part summarizes the vast majority of clinical immunoPET studies applying semi-quantitative methodologies. The second part focuses on a handful of studies applying pharmacokinetic models and includes preclinical and simulation studies. Finally, the potential and challenges of immunoPET quantification methodologies are discussed within the context of the recent technological advancements provided by long axial field of view PET/CT scanners. [ABSTRACT FROM AUTHOR]

This study investigates the impact of zirconium-based KZC series crosslinkers with varying zirconium contents and the polyamine-based crosslinker (PBC) on the properties of coated paper, focusing on key performance metrics such as viscosity, wet rub and pick resistance, dry pick resistance, gloss, brightness, ink set-off, and print mottle. The findings reveal that crosslinkers' type and concentration significantly influence the coating colors' viscosity, with PBC demonstrating lower low shear viscosity at lower concentrations. The KZC series showed stable viscosity across a zirconium content range of 7% to 20%, and both crosslinker types enhanced wet rub resistance at higher concentrations. Notably, the KZC series, particularly KZC7, exhibited superior wet pick resistance at increased concentrations, highlighting its effectiveness in enhancing the durability of the coating layer. All crosslinkers maintained excellent dry pick resistance, ensuring robust coating performance. While gloss and brightness were generally unaffected, KZC20, which had the highest zirconium content, slightly reduced these optical properties. Ink set-off tests indicated that the KZC series performed better at lower concentrations, whereas higher concentrations led to increased ink set-off, potentially due to over-crosslinking. Print mottle remained consistent across all crosslinkers, indicating uniform coating quality. Overall, the zirconium-based KZC series significantly enhances wet resistance and maintains high performance across various properties, though it may slightly reduce gloss and brightness and increase ink set-off at higher concentrations. PBC offers a balanced performance profile, emphasizing the need for careful crosslinker type and concentration optimization to achieve the desired coating properties for specific applications. This comprehensive evaluation provides valuable insights for developing and optimizing high-performance coated papers. [ABSTRACT FROM AUTHOR]

Introduction: Sodium zirconium cyclosilicate (SZC) is a nonabsorbed cationexchanger approved in China for the treatment of hyperkalemia [HK; serum potassium (sK+) levels >5.0 mmol/L]. This is the first real-world study aimed to assess the effectiveness, safety, and treatment patterns of SZC in Chinese patients with HK. Here we present the results of the first interim analysis. Methods: This multicenter, prospective, cohort study included patients aged =18 years with documented HK within 1-year before study enrollment day. These patients were followed up for 6 months from the enrollment day after initiating SZC treatment. The treatment was categorized into correction phase (FAS-P1) and maintenance phase (FAS-P2 new and ongoing users). Subgroup analysis was performed in patients on hemodialysis (FAS-H). The primary objective was evaluation of safety profile of SZC; secondary objectives included assessment of treatment patterns of SZC and its effectiveness. Results: Of 421 screened patients, 193, 354, and 162 patients were enrolled in the FAS-P1, FAS-P2, and FAS-H groups, respectively. sK+ levels were reduced significantly from 5.9 mmol/L to 5.0 mmol/L after the correction phase. For the maintenance phase, the mean sK+ levels were maintained at 5.2 mmol/L and 5.0 mmol/L in the FAS-P2 new and ongoing user, respectively, and 5.3 mmol/L in the FAS-H subgroup. A considerable proportion of patients showed normokalemia after 48 h of SZC treatment (FAS-P1:51.3%) which was maintained up to 6 months in the maintenance phase (FAS-P2:44%). SZC was well-tolerated. Conclusion: SZC was effective and safe for the treatment of HK in real-world clinical practice in China. [ABSTRACT FROM AUTHOR]

Transition metal nitride (TMN) films hold great promise in temperature sensing due to their excellent stability, but the decreased sensitivity with increasing temperature has limited their adaptability to various temperature scenarios. In this paper, a method for regulating the high-sensitivity temperature range (HSTR) of the temperature sensors based on the zirconium aluminum nitride (Zr1−xAlxN) films by adjusting the Al content is proposed. According to the resistance–temperature (R–T) curves from 4.2 to 300 K, the metal-to-semiconductor transition was observed when Al atoms were doped in ZrN. Moreover, the semiconductor R–T curve gradually shifts to 300 K and then backs to cryogenics by continuously increasing the Al content in Zr1−xAlxN. Interestingly, the phase transition from cubic (c)-ZrN to cubic (c)-Zr1−xAlxN, then to the mixed phases of c-Zr1−xAlxN and wurtzite aluminum nitride (w-AlN), and, finally, to the hexagonal close packed-zirconium (α-Zr) precipitation was observed with increasing Al content, which shows high consistency with R–T characteristics. Moreover, the bandgap energy initially increases and then decreases, which matches well with the phase and electrical transitions. Based on the experimental results, we build a physical model that can clarify the above phase and electrical transition when the Al content in Zr1−xAlxN films changes, proposing that the effect of Al content on the phase and electrical characteristics can realize the control of the HSTR of Zr1−xAlxN films. These findings suggest ideas for developing temperature sensors based on TMN films with high sensitivity across a wide temperature range. [ABSTRACT FROM AUTHOR]

The sustainable and ecofriendly synthesis of transition metal oxide‐based nanomaterials has always been a matter of concern. In this study, a bioinspired synthesis route was adopted to synthesize ZrO2‐Zr3Er4O12‐based mixed nanomaterial using leaf extract of medicinal plant Amaranthus viridis as reducing and stabilizing agent in replacement of the obnoxious chemicals which are a great threat to the sustainable environment. The synthesized material revealed the spherical shaped morphology through scanning electron microscopy, whereas crystal size of 15.7 nm was observed through Xray‐diffraction, and band gap value of 2.7 eV was acquired using Tauc plot. Newly synthesized ZrO2‐Zr3Er4O12 nanocomposite was then investigated for its role as electrocatalyst in a generation of energy through the hydrogen evolution reaction and oxygen evolution reaction. The ZrO2‐Zr3Er4O12‐based electrocatalyst showed better potential for hydrogen evolution reaction measurements with the overpotential value of 242 mV. Furthermore, the notable capacitance value of 495.6 F/g was obtained through cyclic voltammetry for energy storage studies. The cyclic stability was also analyzed using linear sweep voltammetry and results showed promising stability for 2000 cycles. Consequently, the green and economical synthesis route as well as promising electrochemical behavior of ZrO2‐Zr3Er4O12‐based electrode make it feasible choice for large scale application. [ABSTRACT FROM AUTHOR]

By employing a co‐sputtering technique, combinatorial thin film libraries in the Ti–Zr system are produced. The libraries have a compositional spread ranging from 40 to 70 at% Ti. The confocal geometry of the sputtering system is maintained for the production of all thin films. The microstructural and crystallographic properties are elucidated by energy dispersive X‐ray spectroscopy (EDX), X‐ray diffraction (XRD), and scanning electron microscopy (SEM) analysis. Furthermore, contact angle measurements and nanoindentations are performed to map the wettability, hardness, and elastic modulus of the alloy system. The electrochemical properties, i.e., the oxide film formation factor and the relative permittivity of anodically grown oxides on the parent metal alloys are determined. The measurements are performed in phosphate‐buffered saline in order to best simulate a biological environment. A linear shift in the properties is observed along the compositional gradient for the EDX, XRD, and SEM analysis. For all other sets of measurements deviations from the linear behavior, are observed around the 60 at% Ti concentrations. This coincides with the formation of a congruent alloy in bulk material. The observed changes however, deviated also from expectations for bulk alloys. The implications and potential for those alloys as implant material are discussed in the following. [ABSTRACT FROM AUTHOR]

Nanowire‐MnO2 and a series of Zr‐doped MnO2 catalysts with different Zr/Mn molar ratios were successively prepared by hydrothermal and impregnation methods. The Zr‐doped MnO2 catalyst with Zr/Mn molar ratio of 0.04 and calcination temperature of 400 °C, proved to be the optimal that possessed the highest low‐temperature denitration efficiency. It showed the NO conversion of ~92 % and N2 selectivity of ~80 % at 150 °C. Characterization results demonstrated that the main active phase of the catalyst was β‐MnO2, Zr atoms interacted with Mn atoms, and Zr doping increased the structural defects, oxygen vacancies and weak acid sites, which effectively enhanced the low‐temperature denitration activity and N2 selectivity of β‐MnO2, also improved the water and sulphur resistance to some extent. [ABSTRACT FROM AUTHOR]

Zirconium terephthalate UiO-66 has aroused great interest in catalysis since it exhibits significant flexibility and compatibility for accommodating a high number of defects as well as exceptional thermal and chemical stability. Until now, many works have focused on the modulations of the Zr6-oxo clusters in UiO-66 in terms of diverse synthesis, advanced characterizations, and their catalytic applications. To achieve high catalytic efficiency, it is still highly desired for rationally constructing and modulating the Zr6-oxo clusters with exposed catalytic sites and diverse microenvironments for advanced catalysis. In this review, we provide a comprehensive summary of recent progress on the synthesis of defective UiO-66, qualitative and quantitative characterizations, as well as a logical overview of heterogeneous catalytic applications over the past few years. Finally, the outlooks for the research paradigm of defective UiO-66 are discussed. [ABSTRACT FROM AUTHOR]

The sol–gel process is a green method used in the last few decades to synthesize new organic–inorganic phosphorus-containing hybrid materials. The sol–gel synthesis is a green method because it takes place in mild conditions, mostly by using water or alcohol as solvents, at room temperature. Therefore, the sol–gel method is, among others, a promising route for obtaining metal-phosphonate networks. In addition to phosphorus, the obtained hybrid materials could also contain titanium, zirconium, boron, and other elements, which influence their properties. The sol–gel process has two steps: first, the sol formation, and second, the transition to the gel phase. In other words, the sol–gel process converts the precursors into a colloidal solution (sol), followed by obtaining a network (gel). By using the sol–gel method, different organic moieties could be introduced into an inorganic matrix, resulting in organic–inorganic hybrid structures (sometimes they are also referred as organic–inorganic copolymers). [ABSTRACT FROM AUTHOR]

Zirconium and hafnium have opposite nuclear properties and are used very differently in the nuclear industry. However, hafnium is a common metal impurity in zirconium, and the chemical properties of the two are very similar except for nuclear properties, and it is difficult to separate and detect them. At present, the detection of hafnium content in zirconium is usually achieved by using an inductively coupled plasma (ICP) spectrometer, but ICP equipment is expensive, and the detection cost is high. Therefore, it is necessary to develop a simple and low-cost method for the determination of hafnium content in zirconium. Based on this, this paper takes the spectrophotometric method as a starting point. Through a series of experiments on the influence of pH and concentrations of the color-developing agent xylenol orange sodium salt on the absorbance of zirconium and hafnium ions, the appropriate variables are selected to detect the content of hafnium in zirconium. Finally, according to the measured absorbance and total ion concentration, by comparing the working curve of zirconium and hafnium ions, the content of hafnium in zirconium is calculated based on the lever principle. [ABSTRACT FROM AUTHOR]

In order to contribute to the sufficient supply of clinical 99mTc(VII), the sorption behavior of neutron-produced 99Mo(VI) was investigated on synthetized single and binary Ti and Zr xerogels treated at different temperatures, under normal operating conditions. Materials were prepared by the sol–gel method and characterized by several techniques. Sorption batch systems were performed using 99Mo radiotracer to determine the metallic affinity as a function of pH, and a methodology was developed in order to obtain the maximum capacities by surface saturation, where the Ti-388, TiZr-388 (3:1) and Zr-388 samples showed the most noteworthy sorption behaviors (33.1 ± 0.34 mg/g at pH ∼ 6.0, 31.7 ± 0.27 mg/g at pH ∼ 6.5, and 23.5 ± 0.61 mg/g at pH ∼ 6.8, respectively). The molybdenum-99 sorption behavior was also studied by fitting to the Freundlich and Langmuir models, and all xerogels could be described as heterogeneous materials with favorable 99Mo sorption properties. Finally, preliminary studies of clinical-scale 99Mo/99mTc generators were performed, the results revealed the next maximum 99mTc elution yield order Ti-388 (89.6 %) > TiZr-388 (3:1) (86.7 %) > Zr-388 (77.7 %). [ABSTRACT FROM AUTHOR]

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Obtaining precise parameters of deformation modes remains a significant challenge in materials science research. Critical resolved shear stresses (CRSS) and work hardening, particularly in hexagonal metals, are crucial parameters for constitutive laws in crystal plasticity. This paper presents a novel approach to determine CRSS and specific hardening matrix coefficients for commercially pure zirconium (α -Zr) at room temperature. In situ methods are employed to measure displacement fields using grids applied to the sample surface, while a comprehensive characterization of the activated deformation systems is performed via SEM and TEM. The CRSS for prismatic 〈 a 〉 , pyramidal 〈 a 〉 , and 10 1 ¯ 2 and 1 1 2 ¯ 1 twinning systems, as well as the self-hardening for prismatic slip and several work-hardening coefficients (for prismatic/prismatic and prismatic/pyramidal interactions), are reported in Zr single crystals. Finally, the results are compared with findings from the literature and atomistic simulations. [ABSTRACT FROM AUTHOR]

Fe-containing intermetallic compounds (IMCs) are among the most detrimental second phases in aluminum alloys. One particularly harmful type is θ-Al13Fe4, which exhibits a needle- or plate-like morphology, leading to greater degradation of mechanical properties compared to other Fe-IMCs with more compact structures, such as α-Al15(Fe,Mn)3Si2. The addition of alloying elements is a crucial strategy for modifying the microstructure during the solidification process of aluminum alloys. This study investigates the effects of adding vanadium (V) and zirconium (Zr) on the morphology and crystal chemistry of θ-Al13Fe4 in an Al-4Fe alloy, employing a combination of experimental observations, first-principle calculations, and thermodynamic analysis. Our findings indicate that zirconium significantly refines both the primary θ-Al13Fe4 particles and the α-Al grains. Additionally, a small amount of vanadium can be incorporated into one of the Wyckoff 4i Al sites in θ-Al13Fe4, rather than occupying any Fe sites, under casting conditions, in addition to the formation of binary Al-V phases. [ABSTRACT FROM AUTHOR]

In this study, the hydrothermal corrosion behavior of zirconium nitride (ZrN) ceramics used as a surrogate nuclear fuel of UN, which were added with different amounts of CrN/Cr2N (0, 10, 20, and 30 vol.%), was investigated with the objective of increasing the loss‐of‐coolant accident (LOCA) tolerance of pressurized water reactor fuel. The ZrN‐based ceramic samples with a density exceeding 98% were fabricated by using a spark plasma sintering system at 1700°C and applied stress of 30 MPa. Following 30 min of hydrothermal corrosion at 300°C, the oxidation layer thickness of pure ZrN ceramics was 9.11 ± 1.96 µm, whereas that of 30 vol.% CrN/Cr2N‐ZrN was only 1.23 ± 0.3 µm, which indicated that CrN/Cr2N offered an excellent protection effect for ZrN. This work can, thus, provide engineering design guidance for the UN with high uranium density to increase the LOCA tolerance of current nuclear power generation systems. [ABSTRACT FROM AUTHOR]

Developing high‐rate lithium‐metal battery (LMB) with superior energy density and operation durability is of significance, which shows enormous potential to be extensively applied. However, the commercialized polyolefin separators exhibit inferior ability to resist the elevated internal temperature and inhibit the lithium (Li) dendrite growth, especially for LMBs under high‐rate operations. With undesired Li+‐anion solvated structures in the electrolyte, previous separator modification strategies usually meet a dilemma to simultaneously increase the Li+ transference number and decrease the anion transference number. Here, a facile and scalable strategy are reported to prepare high‐performance sandwiched separators with polyolefin separators coated by single‐atom zirconium coordination polyimide aerogel (Zr‐PIA) layers, which can achieve a stable LMB operation at 20 C for 2700 cycles with a capacity retention of 94.6%, substantially outperforming its counterpart separator without Zr. Both the experimental and theoretical studies suggest that the Zr‐PIA layer with nanoporous architecture and anion‐trapping Zr sites can effectively increase the Li+ transference number without sacrificing the overall ion conductivity, enabling a rapid, selective and uniform Li+ flux through the separator. Such features can facilitate homogeneous the Li nucleation/deposition and mitigate Li dendrite growth, leading to enhanced battery durability and safety. [ABSTRACT FROM AUTHOR]

Functional composite layers composed of an amino-functionalized zirconium 1,4-dicarboxybenzene metal–organic framework were constructed on zinc anodes to mitigate the interface disturbances in aqueous batteries. These layers enable robust Zn2+ adsorption and homogenized Zn2+ transport and deposition kinetics, facilitating achieving high stability in a symmetric cell (3500 h) and a full cell (35 000 cycles, 96.7%). [ABSTRACT FROM AUTHOR]

Experiments using a transmission electron microscope decomposed zirconium acetylacetonate with an electron beam, forming zirconium nanoparticles on graphene. Continued electron irradiation transformed these nanoparticles into atomically thick zirconium islets (zirconene islets) within the graphene lattice. The electron beam caused zirconium atom dislocations and vacancies that are rapidly refilled, a process repeating until the vacancies evolved into zirconium nanoribbons before breaking. This study offers insights into the electron‐driven growth and degradation of zirconene islets, showcasing a method to fabricate freestanding zirconenes for use as atomically thin coatings in extreme environments. [ABSTRACT FROM AUTHOR]

Porous anodic oxides have become a research hotspot, but their formation mechanisms are still controversial. The classical field-assisted dissolution theory (FADT) is a theory of top-down dissolution to form nanotubes. However, certain key problems such as the three-stage current-time curve in anodizing process cannot be explained by this theory. The oxygen bubble mold (OBM) is a new mechanism of bottom-up growth of nanotubes, which can explain the phenomenon that cannot be explained by the FADT. Compared to the anodic TiO 2 nanotubes, ZrO 2 nanotubes have a more complex anodizing current-time curve which is not studied sufficiently. Under certain conditions, there are double complete three-stage current-time curves and two-layer nanotubes. In this study, to explore the formation mechanism of anodic ZrO 2 nanotubes, the current-time curve and the interesting morphology were analyzed, after zirconium anodizing and SEM characterizing. An interesting three-layer structure composed of upper nanotubes, dense layer and lower nanotubes formed by zirconium anodizing is reported for the first time. The lower nanotubes and the dense layer are tightly bonding, which strongly refutes the FADT. The OBM was used to explain this phenomenon, which promoted the development of the formation mechanism of anodic ZrO 2 nanotubes. [ABSTRACT FROM AUTHOR]

A simple method was developed for the determination of REEs, Zr, Hf, Th and U in ultramafic rocks by inductively coupled plasma‐mass spectrometry with a combination of RE and UTEVA extraction resins for their separation and pre‐concentration. Ultramafic rocks were digested with HNO3‐HF‐HClO4 and finally turned into 11 mol l−1 HCl solutions together with H3BO3 to remove insoluble fluorides. The removal of matrix elements was achieved during the loading procedure. Following this, REEs on RE resin, and Zr, Hf, Th and U on UTEVA resin were eluted with 10 ml of 0.24 mol l−1 HCl, with recoveries better than 94.4%. This method was validated using reference materials JP‐1, DTS‐2B, OKUM, UB‐N, MUH‐1 and DZΣ‐2, and the measurement results for target analytes were comparable to literature values, indicating its applicability to the determination of REEs, Zr, Hf, Th and U at ultra‐trace level in ultramafic rocks. [ABSTRACT FROM AUTHOR]

Measurement of the thermophysical properties of liquid metals is a highly challenging task due to numerous problems encountered above the fusion point. Properties such as density and surface tension have been widely investigated, while few studies address thermal diffusivity. In this paper we describe an original methodology for estimating the thermal diffusivity of metals in the liquid state. The proposed experimental setup is based on the traditional flash method. Its design ensures that samples of liquid metal are self-contained, preventing contamination and allowing measurements at high temperature. Results for both solid and liquid iron and 304 stainless steel are presented and compared to data suggested by the literature for validation. Then, for the first time, thermal diffusivity measurement of liquid zirconium is performed giving results up to 2450 K. Giving the high sensitivity of the results to the thickness variation we propose a numerical approach to deal with this issue. [ABSTRACT FROM AUTHOR]

Objective: This study was designed to compare discomfort/pain after periodontal and peri‐implant probing in patients with titanium compared with zirconium implants. Methods: One examiner recruited and examined 70 patients, each of whom had a dental implant with a contralateral tooth; 37 patients had titanium implants of various types and 33 patients had zirconium implants; one implant was analyzed for each patient. Periodontal and peri‐implant probing pocket depth (PPD) and clinical attachment level (CAL) were assessed. Immediately after probing, patients rated their discomfort/pain with a visual analog scale (VAS). The emergence profiles of implant crowns were assessed on periapical radiographs of the implants. Results: Seventy patients with a median age of 55 years (interquartile range [IQR]: 42–65 years), including 43 females and 16 current smokers, were examined. The mean PPD and bleeding on probing (BOP) were higher around implants than around teeth (p <.001). CAL and suppuration were well‐balanced between implants and teeth. Peri‐implant probing caused significantly more discomfort/pain than periodontal probing [median VAS score: 12.5 (IQR 4–22) vs. 9 (2–15); p <.001]. Logistic regression revealed that discomfort/pain after peri‐implant probing was less intense in patients who had taken analgesic medication (p =.021) and around titanium implants (p =.037). Conclusions: Peri‐implant probing caused significantly more discomfort/pain than periodontal probing. Patients who had taken analgesic medication experienced less discomfort and pain with peri‐implant probing than those who had not; furthermore, titanium implants were associated with less pain than zirconium implants. [ABSTRACT FROM AUTHOR]

The Pauli exclusion principle (PEP), a cornerstone of quantum mechanics and whole science, states that in a system, two fermions can not simultaneously occupy the same quantum state. Several experimental tests have been performed to place increasingly stringent bounds on the validity of PEP. Among these, the series of VIP experiments, performed at the Gran Sasso Underground National Laboratory of INFN, is searching for PEP-violating atomic X-ray transitions in copper. In this paper, the upgraded VIP-3 setup is described, designed to extend these investigations to higher-Z elements such as zirconium, silver, palladium, and tin. We detail the enhanced design of this setup, including the implementation of cutting-edge, 1 mm thick, silicon drift detectors, which significantly improve the measurement sensitivity at higher energies. Additionally, we present calculations of expected PEP-violating energy shifts in the characteristic lines of these elements, performed using the multi-configurational Dirac–Fock method from first principles. The VIP-3 realization will contribute to ongoing research into PEP violation for different elements, offering new insights and directions for future studies. [ABSTRACT FROM AUTHOR]

• Hyperkalemia is a common postoperative complication in kidney transplant recipients. • Limited data describing safety/tolerability/efficacy of novel potassium binders. • Patiromer and sodium zirconium cyclosilicate (SZ-9) appear safe and well-tolerated. • Patiromer and SZ-9 did not reduce posttransplant dialysis need or hospitalization. Evaluate the safety/efficacy of novel potassium binders (patiromer, sodium zirconium cyclosilicate [SZ-9]) for early postoperative hyperkalemia following kidney transplantation. Retrospective, single-center, cohort study of deceased-donor kidney recipients transplanted between 1/2018 and 12/2020. Potassium-binder use was evaluated from immediately posttransplant until discharge. Potassium binders were administered ≥2 hours before/after medications. A total of 179 patients were included, 24 (13%) of whom received potassium binders (16 [67%] patiromer, 7 [29%] SZ-9, 1 [4%] both) for a mean of 2.5 (±3.18) doses. Peak potassium levels were higher in the potassium-binder group (6.05 vs 5.35 mEq/L; P <.001). More patients on potassium binders transitioned to atovaquone than those on no binders (n = 21 [100%] vs n = 112 [75%], respectively; P =.005). Delayed graft function (DGF) was observed in 100 (56%) patients, with a higher proportion receiving potassium binders (18 [75%] vs 82 [53%], respectively; P =.042). There was no difference between groups in number of posttransplant dialysis sessions required in the general study population (P =.2), nor in the DGF group (P =.12). No difference was noted in the incidence of ileus (P =.2), or gastrointestinal symptoms (diarrhea, nausea, vomiting; P =.6). Of the 24 patients who received inpatient binders, 9 (37.5%) were discharged and remained on them for a mean of 46 (±49) days. Patiromer and SZ-9 appear safe in the early posttransplant period, but larger prospective trials are needed. Potassium-binder use does not appear to be associated with fewer dialysis sessions in DGF patients, however, they may be used as additional tools for lowering potassium in these patients. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to assess the influence of translucent monolithic versus bilayered crowns and whether the use of a CoCr base abutments affects the fatigue and fracture resistance of screwed implant‐supported single crowns with external connections under mechanical cycling. Materials and Methods: Fifty specimens were divided into groups: (1) metal–ceramic (MC) crown, (2) veneered zirconia crown (Zr), (3) veneered zirconia crown with a CoCr base abutment (ZrB), (4) monolithic translucent zirconia crown (MZr), and (5) monolithic translucent zirconia crown with a CoCr base abutment (MZrB). Specimens underwent mechanical cycling (5 × 106 cycles; 150 N) evaluating fatigue resistance (number of failures) and those that failed were subsequently subjected to fractographic analyses (stereomicroscope and scanning electron microscope) to evaluate failure location and area, and maximum fracture load was also measured. Results: The failure‐related survival rate (100%) and maximum fracture resistance of the MZrB were significantly higher than those of MC and Zr (50%; p < 0.05). There were no significant differences in the failure rate and fracture resistance when a CoCr base abutment was used or not in the translucent monolithic Zr groups (p > 0.05;MZrB vs. MZr). Failure location, with MC crowns' fractures, noted at the screw area (p = 0.043), while all‐ceramic crowns were mostly in the cuspid and to failure area, the Zr group had the largest mean (15.55 ± 9.17 mm2) among the groups, significant difference only when compared with MC (1.62 ± 0.81 mm2) (p = 0.025). Conclusions: Translucent monolithic zirconia crowns exhibited significantly higher fatigue and fracture resistance compared with conventional MC and bilayered crowns. Clinical Significance: The appropriate choice of material and manufacturing technique is crucial for predicting the higher clinical performance of single crowns. Enhanced mechanical resistance in terms of fatigue and fracture resistance can be achieved by replacing MC and bilayered restorations with computer‐aided design and computer‐aided manufacturing monolithic zirconia. [ABSTRACT FROM AUTHOR]

In a part of the historical reactivity-initiated accident (RIA) simulated tests on high-burnup fuels performed at the Nuclear Safety Research Reactor, the fuel failure caused by pellet-cladding mechanical interaction (PCMI) led to splitting into upper- and lower-part pieces or even fragmentation of the cladding tube. A massive release of fuel fragments accompanied this fracture pattern change from previously known axial cracks and thus identified as a potential concern in safety evaluation regarding core coolability. Dedicated out-of-pile mechanical tests were performed with unirradiated Zircaloy-4 cladding specimens to clarify the condition of such fracture pattern change. The specimens were pre-hydrided and subjected to loading with axial-to-hoop strain ratios of ℇz/ℇθ = 0.5–1.25, simulating the effects of hydrogen embrittlement and pellet-cladding mechanical bonding of high-burnup fuels, respectively. The results indicate that higher biaxiality of the loading and lower ductility (failure strain level) assist the fracture pattern change. This study proposes a conservative criterion that a PCMI failure splits the cladding tube into more than two pieces when strain ratio ℇz/ℇθ >0.75 and a concurrent hoop strain < 1.7% at the failure instant. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents the results of the study of the processes of self-propagating high-temperature synthesis of Zr-1%B alloy and its refining by electron beam melting. Experiments on the influence of boron's amorphous and crystalline modifications on the safety parameters of the synthesis process of Zr-1%B alloy necessitated the conversion of amorphous boron into crystalline form by electron beam melting, with an increase in its purity from 94% to 99.9%. High efficiency of vacuum induction and electron beam equipment was demonstrated, which provided a high purity of the Zr-1%B alloy of at least 99.9%. The alloy ingots had a uniform distribution of the alloying element (boron) all over the volume. The obtained alloy is suitable for the production of materials with thermal neutron capture cross-sections of up to 40 barns for neutron protection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Soil Sciences & Agricultural Engineering is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The results of modeling and research of casting, rolling, and extrusion processes for producing wire from Al–Zr system alloys and determining its physical and mechanical properties have been presented. When implementing combined processes for processing aluminum alloys, the number of operations is significantly reduced, productivity and yield are increased. As a result of the conducted research, the influence of alloy preparation modes and their chemical composition on the physical, mechanical and electrical properties of longish semifinished products from Al–Zr system alloys obtained by combined rolling-extrusion (CRE) and ingotless rolling-extrusion (IRE) methods were investigated. The simulation of the CRE process for one of these alloys of the system was carried out in the DEFORM 3D software package using data on its rheological properties obtained by the hot torsion method. Based on the modeling results, the optimal modes for conducting experimental studies were selected. The features of metal forming were experimentally studied, the temperature-velocity and technological parameters of combined processing were found, as well as the properties of cast billets, including those obtained using an electromagnetic mold (EMM). The results of experimental studies of the CRE and IRE processes suggest that it is possible to obtain longish deformed semifinished products from alloys Al–Zr system with a level of physical, mechanical and electrical properties that meet international standards. At all technological stages, including drawing, the structure of the metal was studied, and data on the physical and mechanical properties of hot-extruded rods and wire in cold-deformed and annealed states was obtained. The heat resistance of wire made from the investigated alloys was studied and it was found that after testing at a temperature of 280 °C and a holding time of 1 h, it satisfies the requirements of the AT3 type standard with a maximum permissible long-term operating temperature of 210 °C. Recommendations are given for industrial implementation; alloys containing 0.15–0.20% zirconium and 0.10–0.15% iron are recommended for the manufacture of AT1 type wire without heat treatment, as well as 0.25–0.30% Zr and 0.2–0.25% Fe for AT3 wire type with heat treatment.

The rise in carbon dioxide concentration is a primary anthropogenic source of severe climate change and ecological issues. Catalytic hydrogenation of CO2 into value-added chemicals and fuels including methanol is one of the attractive environmentally friendly ways to valorize carbon-containing feedstock and reduce global CO2 emissions. However, enhancing catalytic activity to achieve high methanol yield and selectivity while maintaining stability remains a major challenge. This study investigated the promotion of Cu/MOF-5 catalysts with varying loadings of ZrO₂ to determine its effects on catalytic performance in CO₂ hydrogenation. The copper loading was kept constant while the ZrO₂ content on the MOF-5 support was varied via the impregnation method. The addition of ZrO₂ was found to influence the BET surface area, suggesting the presence of amorphous ZrO₂, as its crystalline phases were not detected in x-ray diffractograms. Catalytic results demonstrated that ZrO₂ addition enhanced the catalytic activity, with increased CO₂ conversion up to 13.2 %. The results showed a correlation between catalytic performance and the reducibility of the active metal, driven by the amount of ZrO₂ present. The catalyst with the highest ZrO₂ loading exhibited the best performance, attributed to its increased surface area and enhanced reducibility. Under optimized conditions (GHSV of 1350 h⁻¹, temperature of 200 °C, and pressure of 30 bar), the catalyst achieved 100 % methanol selectivity. This study underscores the significant role of ZrO₂ as a promoter in enhancing the activity and selectivity of Cu/MOF-5 catalysts, providing critical insights into the design of efficient catalytic systems for CO₂ hydrogenation.

To explore the effect of micro-Zr alloying on the hot deformation microstructure of 6082 aluminum alloy and its subsequent recrystallization during heat treatment， the hot deformation behavior and micro-orientation evolution of 6082 aluminum alloy containing Zr at different strain rates （0.01，1 s-1） were comparatively studied. The evolution process of grain structure before and after heat treatment was analyzed， and the regulatory effect of Zr addition on the thermally deformed sub-grains and recrystallization of 6082 aluminum alloy was further discussed. The results show that the addition of Zr makes the recrystallization of 6082 aluminum alloy during the hot deformation process mainly perform discontinuous dynamic recrystallization， and the recrystallization generated by the particle stimulated nucleation（PSN）mechanism also occurs， and minor Zr addition also plays a role in inhibiting recrystallization in the hot deformation process. After the micro-Zr alloying， the subgrain size decreases， the dislocation density increases， the recrystallization level decreases， and the recrystallization level of the sample at a higher strain rate is lower， and the addition of Zr promotes the generation of the discontinuous dynamic recrystallization of 6082 aluminum alloy during hot deformation.

The paper presents the results of the study of the processes of self-propagating high-temperature synthesis of Zr-1%B alloy and its refining by electron beam melting. Experiments on the influence of boron’s amorphous and crystalline modifications on the safety parameters of the synthesis process of Zr-1%B alloy necessitated the conversion of amorphous boron into crystalline form by electron beam melting, with an increase in its purity from 94% to 99.9%. High efficiency of vacuum induction and electron beam equipment was demonstrated, which provided a high purity of the Zr-1%B alloy of at least 99.9%. The alloy ingots had a uniform distribution of the alloying element (boron) all over the volume. The obtained alloy is suitable for the production of materials with thermal neutron capture cross-sections of up to 40 barns for neutron protection.

The paper examines the effect of precipitation hardening temperature on selected properties of AlSi5Cu2Mg alloy alloyed by 0.20 wt.% of Zr. The newly developed AlSi5Cu2Mg alloy intended for cylinder head castings is specific due to its limited Ti content, which prevents the use of standard Al-Ti-B type grain refiners. Zr added in the form of AlZr20 master alloy acts as a grain refiner. The grain refinement effect of Zr positively affects the mechanical properties. However, the physical properties defining the lifetime of cylinder head castings are not affected by the presence of Zr-rich phases. For this reason, the research focuses on the proposal of the optimal T6 heat treatment procedure in order to positively influence the physical and mechanical properties of the AlSi5Cu2Mg alloy. For the research, four T6 thermal regimes with graduated aging temperatures by 20°C from 180 to 240°C ± 5°C were selected. The results showed that increasing aging temperature positively affects physical properties, especially thermal conductivity, and mechanical properties of Rm, Rp0.2, and HBW. On the other hand, with increasing aging temperature up to 220°C ± 5°C, a negative decrease in ductility was achieved. Optimum ductility of, especially, AlSi5Cu2Mg alloy with 0.20 wt.% Zr was achieved by the T6-240 thermal regime. Optimal combination of thermal conductivity and mechanical properties of the AlSi5Cu2Mg alloy with 0.20 wt.% Zr was achieved by the T6-240 heat treatment due to the requirements placed on cylinder head castings.