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Vanadium and molybdenum concentrations in particulate from Palermo (Italy): analytical methods using

Diana AMORELLO,Santino ORECCHIO

《环境科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 605-614 doi: 10.1007/s11783-014-0703-8

摘要: The main purpose of this work was to develop a reliable method for the determination of vanadium (V) and molybdenum (Mo) in atmosphere particles or aerosols because they can not be readily measured using conventional techniques. For this research, 30 particulate samples were collected from five different stations located at Palermo, Italy. We used the catalytic adsorptive stripping voltammetry and differential pulsed voltammetry to measure V and Mo in atmospheric particulate, respectively. The represented method includes advantages of high sensitivity, high selectivity, simplicity, reproducibility, speed and low costs. The quantification limits for V and Mo are, respectively, 0.57 and 0.80 ng·m . The precision, expressed as relative standard deviation (RSD %), was about 2% for both metals. The mean recoveries of added V and Mo were about 99.5% and ranged from 97% to 101%. Vanadium concentrations in particulate samples collected in Palermo area ranged from 0.57 to 7.7 ng·m , while Mo concentrations were in the range 0.8–51 ng·m . In many cases the concentrations of two elements in the particulate samples fall below the detection limits. The mean concentrations for V and Mo in particulate samples, collected in Palermo area, were respectively 3.1 and 5.9 ng·m .

关键词: vanadium     molybdenum     particulate     voltammetry     Palermo    

Molybdenum disulfide@nickel phyllosilicate hybrid for improving the flame retardancy and wear resistance

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2114-2126 doi: 10.1007/s11705-023-2357-1

摘要: In this study, nickel phyllosilicate was synthesized based on molybdenum disulfide (MoS2@NiPS) by the sol-gel method, and then MoS2@NiPS was used to prepare epoxy composites. The thermal stability, flame retardancy, and frictional performances of epoxy composites were studied. With the addition of 3 wt% MoS2@NiPS, the epoxy composite increased the limiting oxygen index from 23.8% to 26.1% and reduced the vertical burning time from 166 s for epoxy resin to 35 s. The residual char of the epoxy composite increased from 11.8 to 20.2 wt%. MoS2@NiPS promoted the graphitization of the residual char, and facilitated the formation of a dense and continuous char layer, thereby improving the fire safety of epoxy resin. The epoxy composite with 3 wt% MoS2@NiPS had excellent wear resistance property with a wear rate of 2.19 × 10−5 mm3·N–1·m–1, which was 68.8% lower than that of epoxy resin. This study presented a practical approach to improve the frictional and fire resistance of epoxy composites.

关键词: molybdenum disulfide     nickel phyllosilicate     epoxy resin     flame retardancy    

Oxidative leaching kinetics of molybdenum-uranium ore in H

T. A. Lasheen, M. E. El-Ahmady, H. B. Hassib, A. S. Helal

《化学科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 95-102 doi: 10.1007/s11705-013-1317-6

摘要: The processing of molybdenum-uranium ore in a sulfuric acid solution using hydrogen peroxide as an oxidant has been investigated. The leaching temperature, hydrogen peroxide concentration, sulfuric acid concentration, leaching time, particle size, liquid-to-solid ratio and agitation speed all have significant effects on the process. The optimum process operating parameters were: temperature: 95°C; H O concentration: 0.5 M; sulfuric acid concentration: 2.5 M; time: 2 h; particle size: 74 μm, liquid-to-solid ratio: 14 ∶ 1 and agitation speed: 600 rpm. Under these experimental conditions, the extraction efficiency of molybdenum was about 98.4%, and the uranium extraction efficiency was about 98.7%. The leaching kinetics of molybdenum showed that the reaction rate of the leaching process is controlled by the chemical reaction at the particle surface. The leaching process follows the kinetic model 1 ? (1? ) = with an apparent activation energy of 40.40 kJ/mole. The temperature, concentrations of H O and H SO and the mesh size are the main factors that influence the leaching rate. The reaction order in H SO was 1.0012 and in H O it was 1.2544.

关键词: leaching of molybdenum     leaching of uranium     kinetics    

Water quality prediction of copper-molybdenum mining-beneficiation wastewater based on the PSO-SVR model

《环境科学与工程前沿(英文)》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1698-9

摘要:

● Data acquisition and pre-processing for wastewater treatment were summarized.

关键词: Chemical oxygen demand     Mining-beneficiation wastewater treatment     Particle swarm optimization     Support vector regression     Artificial neural network    

Catalytic reduction of water pollutants: knowledge gaps, lessons learned, and new opportunities

《环境科学与工程前沿(英文)》 2023年 第17卷 第2期 doi: 10.1007/s11783-023-1626-z

摘要:

● Advances, challenges, and opportunities for catalytic water pollutant reduction.

关键词: Molybdenum     Rhenium     Rhodium     Ruthenium     Catalyst Support     Bromate    

Recent progress in MoS

Soheil RASHIDI, Akshay CARINGULA, Andy NGUYEN, Ijeoma OBI, Chioma OBI, Wei WEI

《能源前沿(英文)》 2019年 第13卷 第2期   页码 251-268 doi: 10.1007/s11708-019-0625-z

摘要: In an era of graphene-based nanomaterials as the most widely studied two-dimensional (2D) materials for enhanced performance of devices and systems in solar energy conversion applications, molybdenum disulfide (MoS ) stands out as a promising alternative 2D material with excellent properties. This review first examined various methods for MoS synthesis. It, then, summarized the unique structure and properties of MoS nanosheets. Finally, it presented the latest advances in the use of MoS nanosheets for important solar energy applications, including solar thermal water purification, photocatalytic process, and photoelectrocatalytic process.

关键词: 2D nanomaterial     molybdenum disulfide     solar energy conversion     solar thermal conversion     photocatalytst     photoelectrocatalyst    

电沉积Mo和Mo-Co合金纳米线用于互联电阻的电阻率改性 Article

Jun Hwan Moon, Taesoon Kim, Youngmin Lee, Seunghyun Kim, Yanghee Kim, Jae-Pyoung Ahn, Jungwoo Choi, Hyuck Mo Lee, Young Keun Kim

《工程(英文)》 2024年 第32卷 第1期   页码 128-138 doi: 10.1016/j.eng.2023.07.017

摘要:

Achieving historically anticipated improvement in the performance of integrated circuits is challenging, due to the increasing cost and complexity of the required technologies with each new generation. To overcome this limitation, the exploration and development of novel interconnect materials and processes are highly desirable in the microelectronics field. Molybdenum (Mo) is attracting attention as an advanced interconnect material due to its small resistivity size effect and high cohesive energy; however, effective processing methods for such materials have not been widely investigated. Here, we investigate the electrochemical behavior of ions in the confined nanopores that affect the electrical properties and microstructures of nanoscale Mo and Mo–Co alloys prepared via template-assisted electrodeposition. Additives in an electrolyte allow the deposition of extremely pure metal materials, due to their interaction with metal ions and nanopores. In this study, boric acid and tetrabutylammonium bisulfate (TBA) were added to an acetate bath to inhibit the hydrogen evolution reaction. TBA accelerated the reduction of Mo at the surface by inducing surface conduction on the nanopores. Metallic Mo nanowires with a 130 nm diameter synthesized through high-aspect-ratio nanopore engineering exhibited a resistivity of (63.0 ± 17.9) μΩ·cm. We also evaluated the resistivities of Mo–Co alloy nanowires at various compositions toward replacing irreducible conventional barrier/liner layers. An intermetallic compound formed at an Mo composition of 28.6 at%, the resistivity of the Mo–Co nanowire was (58.0 ± 10.6) μΩ·cm, indicating its superior electrical and adhesive properties in comparison with those of conventional barriers such as TaN and TiN. Furthermore, density functional theory and non-equilibrium Green’s function calculations confirmed that the vertical resistance of the via structure constructed from Mo-based materials was 21% lower than that of a conventional Cu/Ta/TaN structure.

关键词: Molybdenum     Molybdenum–cobalt     Interconnect     Microstructure     Electrodeposition     Density functional theory    

Oxygen-deficient MoO/NiS heterostructure grown on nickel foam as efficient and durable self-supported electrocatalysts for hydrogen evolution reaction

《化学科学与工程前沿(英文)》 2023年 第17卷 第4期   页码 437-448 doi: 10.1007/s11705-022-2228-1

摘要: High-performance and ultra-durable electrocatalysts are vital for hydrogen evolution reaction (HER) during water splitting. Herein, by one-pot solvothermal method, MoOx/Ni3S2 spheres comprising Ni3S2 nanoparticles inside and oxygen-deficient amorphous MoOx outside in situ grow on Ni foam (NF), to assembly the heterostructure composites of MoOx/Ni3S2/NF. By adjusting volume ratio of the solvents of ethanol to water, the optimized MoOx/Ni3S2/NF-11 exhibits the best HER performance, requiring an extremely low overpotential of 76 mV to achieve the current density of 10 mA∙cm‒2 (η10 = 76 mV) and an ultra-small Tafel slope of 46 mV∙dec‒1 in 0.5 mol∙L‒1 H2SO4. More importantly, the catalyst shows prominent high catalytic stability for HER (> 100 h). The acid-resistant MoOx wraps the inside Ni3S2/NF to ensure the high stability of the catalyst under acidic conditions. Density functional theory calculations confirm that the existing oxygen vacancy and MoOx/Ni3S2 heterostructure are both beneficial to the reduced Gibbs free energy of hydrogen adsorption (|∆GH*|) over Mo sites, which act as main active sites. The heterostructure effectively decreases the formation energy of O vacancy, leading to surface reconstruction of the catalyst, further improving HER performance. The MoOx/Ni3S2/NF is promising to serve as a highly effective and durable electrocatalyst toward HER.

关键词: molybdenum oxides     oxygen vacancies     heterostructure     electrocatalysts     hydrogen evolution reaction    

Enhanced methanation stability of nano-sized MoS

Zhenhua LI, Jia HE, Haiyang WANG, Baowei WANG, Xinbin MA

《化学科学与工程前沿(英文)》 2015年 第9卷 第1期   页码 33-39 doi: 10.1007/s11705-014-1446-6

摘要: A series of unsupported MoS catalysts with or without Al O modification was prepared using a modified thermal decomposition approach. The catalysts were tested for the methanation of carbon monoxide and the optimum one has 25.6 wt-% Al O content. The catalysts were characterized by nitrogen adsorption measurement, X-ray diffraction and transmission electron microscopy. The results show that adding appropriate amount of Al O increases the dispersion of MoS , and the increased interaction force between MoS and Al O can inhibit the sintering of active MoS to some extent.

关键词: unsupported catalyst     molybdenum sulfide     stability     alumina     methanation    

Facile route to achieve MoSe-NiSe on nickel foam as efficient dual functional electrocatalysts for overall water splitting

《能源前沿(英文)》 2022年 第16卷 第3期   页码 483-491 doi: 10.1007/s11708-022-0813-0

摘要: Since the catalytic activity of present nickel-based synthetic selenide is still to be improved, MoSe2-Ni3Se2 was synthesized on nickel foam (NF) (MoSe2-Ni3Se2/NF) by introducing a molybdenum source. After the molybdenum source was introduced, the surface of the catalyst changed from a single-phase structure to a multi-phase structure. The catalyst surface with enriched active sites and the synergistic effect of MoSe2 and Ni3Se2 together enhance the hydrogen evolution reactions (HER), the oxygen evolution reactions (OER), and electrocatalytic total water splitting activity of the catalyst. The overpotential of the MoSe2-Ni3Se2/NF electrocatalyst is only 259 mV and 395 mV at a current density of 100 mA/cm2 for HER and OER, respectively. MoSe2-Ni3Se2/NF with a two-electrode system attains a current density of 10 mA/cm2 at 1.60 V. In addition, the overpotential of HER and OER of MoSe2-Ni3Se2/NF within 80000 s and the decomposition voltage of electrocatalytic total water decomposition hardly changed, showing an extremely strong stability. The improvement of MoSe2-Ni3Se2/NF catalytic activity is attributed to the establishment of the multi-phase structure and the optimized inoculation of the multi-component and multi-interface.

关键词: three-dimensional molybdenum nanomaterials     hydrogen evolution reaction     oxygen evolution reaction     overall water splitting    

标题 作者 时间 类型 操作

Vanadium and molybdenum concentrations in particulate from Palermo (Italy): analytical methods using

Diana AMORELLO,Santino ORECCHIO

期刊论文

Molybdenum disulfide@nickel phyllosilicate hybrid for improving the flame retardancy and wear resistance

期刊论文

Oxidative leaching kinetics of molybdenum-uranium ore in H

T. A. Lasheen, M. E. El-Ahmady, H. B. Hassib, A. S. Helal

期刊论文

Water quality prediction of copper-molybdenum mining-beneficiation wastewater based on the PSO-SVR model

期刊论文

Catalytic reduction of water pollutants: knowledge gaps, lessons learned, and new opportunities

期刊论文

Recent progress in MoS

Soheil RASHIDI, Akshay CARINGULA, Andy NGUYEN, Ijeoma OBI, Chioma OBI, Wei WEI

期刊论文

电沉积Mo和Mo-Co合金纳米线用于互联电阻的电阻率改性

Jun Hwan Moon, Taesoon Kim, Youngmin Lee, Seunghyun Kim, Yanghee Kim, Jae-Pyoung Ahn, Jungwoo Choi, Hyuck Mo Lee, Young Keun Kim

期刊论文

Oxygen-deficient MoO/NiS heterostructure grown on nickel foam as efficient and durable self-supported electrocatalysts for hydrogen evolution reaction

期刊论文

Enhanced methanation stability of nano-sized MoS

Zhenhua LI, Jia HE, Haiyang WANG, Baowei WANG, Xinbin MA

期刊论文

Facile route to achieve MoSe-NiSe on nickel foam as efficient dual functional electrocatalysts for overall water splitting

期刊论文