Health & Environmental Research Online (HERO)


Molybdenum (7439-98-7 )


20,705 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Tuning the oxygen reduction reactivity of interconnected porous carbon by incorporation of phosphorus and activity enhancement through blending with 2D metal dichalcogenides materials

Authors: Mutyala, S; Rajaram, R; Karuppasamy, D; Suresh, C; Mathiyarasu, J (2018) HERO ID: 4598177

[Less] Design and construction of strong oxygen reduction reaction (ORR) electrocatalysts with high activity . . . [More] Design and construction of strong oxygen reduction reaction (ORR) electrocatalysts with high activity and durability are the main concerns in proton exchange membrane fuel cells (PEMFCs). In this study, a unique interconnected porous carbon (ICPC) and phosphorus doped ICPC (P-ICPC) were synthesized and utilized as a support matrix for ORR in alkaline medium. The activity of P-ICPC further enhanced by compositing with 2D metal dichalcogenide MoS2 materials through facile hydrothermal method. The structural characterization indicated that the addition of phosphorus created more defective site in the carbon structure. The MoS2/P-ICPC catalyst exhibited enhanced ORR activity, and its performance. is close to commercial Pt/C catalyst with regards to current density and onset potential. The synthesized MoS2/P-ICPC catalyst shows better stability regarding activity even after the 2000 cycles of acceleration test. The electron transfer number (n) obtained for MoS2/P-ICPC is similar to 3.8, indicating that the oxygen reduction reaction proceeds via 4e(-) pathway with the similar kinetics of commercial Pt/C. The current results revealed that the synthesized MoS2/P-ICPC material might be a better catalyst for oxygen reduction reaction. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Journal Article
Journal Article

Few-layer Tellurium: one-dimensional-like layered elementary semiconductor with striking physical properties

Authors: Qiao, J; Pan, Y; Yang, F; Wang, C; Chai, Y; Ji, Wei (2018) HERO ID: 4609128

[Less] Few-layer Tellurium, an elementary semiconductor, succeeds most of striking physical properties that . . . [More] Few-layer Tellurium, an elementary semiconductor, succeeds most of striking physical properties that black phosphorus (BP) offers and could be feasibly synthesized by simple solution-based methods. It is comprised of non-covalently bound parallel Te chains, among which covalent-like feature appears. This feature is, we believe, another demonstration of the previously found covalent-like quasi-bonding (CLQB) where wavefunction hybridization does occur. The strength of this inter-chain CLQB is comparable with that of intra-chain covalent bonding, leading to closed stability of several Te allotropes. It also introduces a tunable bandgap varying from nearly direct 0.31 eV (bulk) to indirect 1.17 eV (2L) and four (two) complex, highly anisotropic and layer-dependent hole (electron) pockets in the first Brillouin zone. It also exhibits an extraordinarily high hole mobility (similar to 10(5) cm(2)/Vs) and strong optical absorption along the non-covalently bound direction, nearly isotropic and layer-dependent optical properties, large ideal strength over 20%, better environmental stability than BP and unusual crossover of force constants for interlayer shear and breathing modes. All these results manifest that the few-layer Te is an extraordinary-high-mobility, high optical absorption, intrinsic-anisotropy, low-cost-fabrication, tunable bandgap, better environmental stability and nearly direct bandgap semiconductor. This "one-dimen sion-like" few-layer Te, together with other geometrically similar layered materials, may promote the emergence of a new family of layered materials. (C) 2018 Science China Press. Published by Elsevier B.V. and Science China Press. All rights reserved.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Post‐Graphene 2D Chemistry: The Emerging Field of Molybdenum Disulfide and Black Phosphorus Functionalization

Authors: Hirsch,; Hauke, F (2018) Angewandte Chemie (International Edition) 57:4338. [Review] HERO ID: 4614815

[Less] The current state of the chemical functionalization of three types of single sheet 2D materials, namely, . . . [More] The current state of the chemical functionalization of three types of single sheet 2D materials, namely, graphene, molybdenum disulfide (MoS2), and black phosphorus (BP) is summarized. Such 2D sheet polymers are currently an emerging field at the interface of synthetic chemistry, physics, and materials science. Both covalent and non‐covalent functionalization of sheet architectures allows a systematic modification of their properties, that is, an improvement of solubility and processability, the prevention of re‐aggregation, or band‐gap tuning. Next to successful functionalization concepts, fundamental challenges are also addressed. These include the insolubility and polydispersity of most 2D sheet polymers, the development of suitable characterization tools, the identification of effective binding strategies, the chemical activation of the usually rather unreactive basal planes for covalent addend binding, and the regioselectivity of plane addition reactions. Although a number of these questions remain elusive in this Review, the first promising concepts to overcome such hurdles are presented.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Crack initiation mechanism in lanthanum-doped titanium-zirconium-molybdenum alloy during sintering and rolling

Authors: Hu, P; Zhou, YuH; Deng, Jie; Li, Shilei; Chen, WenJ; Chang, T; Hu, BoL; Wang, Kshe; Feng, Pfa; Volinsky, AA (2018) HERO ID: 4626487

[Less] Lanthanum-doped titanium-zirconium-molybdenum (La-TZM) alloy was prepared by powder metallurgy and rolling . . . [More] Lanthanum-doped titanium-zirconium-molybdenum (La-TZM) alloy was prepared by powder metallurgy and rolling process. The processing crack and crack initiation mechanisms of La-TZM alloy after sintering, hot rolling and cold rolling were studied by scanning and transmission electron microscopy. The results show that the doped La(NO3)(3), TiH2 and ZrH2 have finer secondary phase in the La-TZM alloy plate. The fracture mode of sintering billet is inter-granular, but the fracture surface of hot rolling exhibited transgranular cleavage. However, the cold rolling is quasi-cleavage fracture. The secondary phase particles tend to hinder the movement of dislocations causing dislocations pile-up. The resulting tensile stress can accelerate cracks nucleation and growth, and the crack propagation will be deflected by the secondary phase particles. The crack initiation can be avoided by reducing local stress concentration caused by dislocations. (C) 2018 Elsevier B.V. All rights reserved.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Femtosecond laser writing of a depressed cladding single mode channel waveguide in high-purity tellurite glass

Authors: Smayev, MP; Dorofeev, VV; Moiseev, AN; Okhrimchuk, AG (2018) HERO ID: 4626992

[Less] High-purity tungstate-tellurite glasses doped with molybdenum, lanthanum or bismuth oxides were investigated . . . [More] High-purity tungstate-tellurite glasses doped with molybdenum, lanthanum or bismuth oxides were investigated from a point of view promising medium for nonlinear optical devices fabrication. A tubular-like architecture was employed for fabrication of waveguides in the of tellurite glasses, in which refractive index change is negative under femtosecond laser writing at 1028 nm. Thermal, nonlinear optical properties and optimal laser writing conditions were determined. The glasses revealed a very high stability against crystallization, high transparency in the visible, near- and mid-IR regions, large values of Kerr nonlinear coefficient that are within the range of (4.3 divided by 5.4).10(-6) cm(2)/GW. The highest values of the nonlinear coefficient were found. for bismuth containing glasses. The single mode waveguide with propagation loss of 0.15 dB/cm at 1064 nm was inscribed in tungstate-tellurite glass.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Role of a membrane-bound aldehyde dehydrogenase complex AldFGH in acetic acid fermentation with Acetobacter pasteurianus SKU1108

Authors: Yakushi, T; Fukunari, S; Kodama, T; Matsutani, M; Nina, S; Kataoka, N; Theeragool, G; Matsushita, K (2018) Applied Microbiology and Biotechnology 102:4549-4561. HERO ID: 4641571

[Less] Acetic acid fermentation is widely considered a consequence of ethanol oxidation by two membrane-bound . . . [More] Acetic acid fermentation is widely considered a consequence of ethanol oxidation by two membrane-bound enzymes-alcohol dehydrogenase and aldehyde dehydrogenase (ALDH)-of acetic acid bacteria. Here, we used a markerless gene disruption method to construct a mutant of the Acetobacter pasteurianus strain SKU1108 with a deletion in the aldH gene, which encodes the large catalytic subunit of a heterotrimeric ALDH complex (AldFGH), to examine the role of AldFGH in acetic acid fermentation. The ΔaldH strain grew less on ethanol-containing medium, i.e., acetic acid fermentation conditions, than the wild-type strain and significantly accumulated acetaldehyde in the culture medium. Unexpectedly, acetaldehyde oxidase activity levels of the intact ΔaldH cells and the ΔaldH cell membranes were similar to those of the wild-type strain, which might be attributed to an additional ALDH isozyme (AldSLC). The apparent KM values of the wild-type and ΔaldH membranes for acetaldehyde were similar to each other, when the cells were cultured in nonfermentation conditions, where ΔaldH cells grow as well as the wild-type cells. However, the membranes of the wild-type cells grown under fermentation conditions showed a 10-fold lower apparent KM value than those of the cells grown under nonfermentation conditions. Under fermentation conditions, transcriptional levels of a gene for AldSLC were 10-fold lower than those under nonfermentation conditions, whereas aldH transcript levels were not dramatically changed under the two conditions. We suggest that A. pasteurianus SKU1108 has two ALDHs, and the AldFGH complex is indispensable for acetic acid fermentation and is the major enzyme under fermentation conditions.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Investigations into the physical properties of SnO2/MoO3 and SnO2/WO3 bi-layered structures along with photocatalytic and antibacterial applications

Authors: Arfaoui, A; Mhamdi, A; Besrour, N; Touihri, S; Ouzari, HI; Alrowaili, ZA; Amlouk, M (2018) HERO ID: 4643525

[Less] This work covers the surface defects effect of SnO2/MoO3 and SnO2/WO3 structures on photocatalysis. . . . [More] This work covers the surface defects effect of SnO2/MoO3 and SnO2/WO3 structures on photocatalysis. One micrometer thick SnO2 bottom layers with porous microstructure and 0.1 thick micrometers of MoO3 or WO3 top layers were consecutively deposited onto glass substrates using the thermal evaporation technique. First, these bi-layered structures were characterized by X-ray diffraction, Raman spectroscopy and atomic force microscopy in order to identify both their structures and their morphological properties. Second, both UV-vis-NIR spectrophotometer measurements and ellipsometry spectroscopic proved that the band gap decreased from SnO2 to coupled SnO2/MoO3 and SnO2/WO3. In addition, a comparison of the photocatalytic degradation of methylene blue (MB) was done under UV-visible light irradiation. The results showed that these structures exhibit promising candidates to degrade methylene blue (MB). Based on the characterization, it was found that SnO2/MoO3 and SnO2/WO3 structure showed higher photocatalytic activity than that of SnO2. This relatively high photocatalytic activity may be attributed to the charge transfer between those bi-layered oxides. Finally, the antibacterial activity test towards Pseudomonas Aeroginosa showed that only SnO2/WO3 thin film has exhibited antibacterial effect.

Journal Article
Journal Article

The role of oxygen vacancies in biomass deoxygenation by reducible zinc/zinc oxide catalysts

Authors: Xiao, X; Bergstrom, H; Saenger, R; Johnson, B; Sun, R; Peterson, A (2018) HERO ID: 4646209

[Less] Selective removal of oxygen is the key challenge in the upgrading of biomass-derived molecules, and . . . [More] Selective removal of oxygen is the key challenge in the upgrading of biomass-derived molecules, and reducible metal oxides have shown the ability to catalytically remove oxygen even at low exogenous H-2 pressures. As opposed to a traditional surface reaction, it is possible that oxygen vacancies provide the active sites in such catalysts, in a Mars-van Krevelen (MvK)-like mechanism. In this work, we use a combination of theoretical calculations and experimental measurements to provide conclusive evidence that this reaction proceeds through such a vacancy-driven mechanism, for the example system of acetic acid deoxygenation to acetaldehyde over reducible zinc oxide surfaces. Density functional theory (DFT) calculations suggest that the catalyst without an oxygen vacancy on the surface was relatively unreactive, due to a strong energetic penalty of breaking the C-O bond, while the presence of the vacancy provides the reducing power to facilitate this elementary step. Experimentally, to examine the role of vacancies directly, we compared the rates and selectivities of acetic acid deoxygenation for standard hydrodeoxygenation conditions with rates in H-2-free conditions starting with reduced Zn metal, in which presumably the only active sites are vacancies created through diffusion. We found a striking similarity in the product distribution, suggesting a common mechanism in both cases. Specifically, metallic zinc with numerous vacant sites on the surface showed a high activity in promoting the deoxygenation reaction, while oxidized zinc (without oxygen vacancies) was fully deactivated. This study suggests that a unique vacancy-driven mechanism is responsible for the reactivity of reducible metal oxide catalysts.

Journal Article
Journal Article

Peroxidase-like activity of MoS2 nanoflakes with different modifications and their application for H2O2 and glucose detection

Authors: Yu, Jie; Ma, D; Mei, L; Gao, Qin; Yin, W; Zhang, X; Yan, L; Gu, Z; Ma, X; Zhao, Y (2018) HERO ID: 4390457

[Less] MoS2 nanoflakes (MoS2 NFs) with a diameter of B390 nm were obtained by a facile one-pot hydrothermal . . . [More] MoS2 nanoflakes (MoS2 NFs) with a diameter of B390 nm were obtained by a facile one-pot hydrothermal method and the NFs exhibited intrinsic peroxidase-like activity. After being modified by commonly used biocompatible surfactants including polyethyleneimine (PEI), polyacrylic acid (PAA), polyvinylpyrrolidone (PVP), and cysteine (Cys), the peroxidase-like catalytic activities of MoS2 NFs were investigated by using 3,30,5,50-tetramethylbenzidine (TMB) and 2,20-azino-bis(3-ethylbenzothiazoline-6sulfonic acid) diammonium salt (ABTS) as chromogenic substrates. Compared to the polymer modified MoS2 NFs, Cys functionalized MoS2 NFs exhibited a high catalytic activity toward H2O2 in the presence of TMB or ABTS. Zeta potential and Michaelis-Menten analyses implied that the electrostatic force induced affinity or repulsion between the MoS2 NFs and substrates, as well as surface modifications of the MoS2 NFs played a key role in the catalytic reactions. Notably, a new peroxidase-like catalytic reaction mechanism was proposed based on the formation of a transient state of Cys-MoS2 NFs containing H2O2 and ABTS, and the catalytic reaction could occur because the Cys on the surface of the MoS2 NFs served as an electron transfer bridge between H2O2 and ABTS. Based on this finding, we also established a platform for colorimetric detection of H2O2 and glucose using Cys-MoS2 NFs as a peroxidase substitution. The limit of detection (LOD) was determined to be 4.103 mmol L-1 for H2O2, and the linear range (LR) was from 0 to 0.3 mmol L-1. The LOD for glucose was 33.51 mmol L-1 and the LR was from 0.05 to 1 mmol L-1, which is suitable for biomedical diagnosis. This work provides a new insight into the catalytic mechanism of peroxidase-like MoS2 NFs, and paves the way for enzyme-like nanomaterials to be used for medical diagnosis.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Label-free electrochemical immunosensor based on flower-like Ag/MoS2/rGO nanocomposites for ultrasensitive detection of carcinoembryonic antigen

Authors: Wang, Y; Wang, Y; Wu, Dan; Ma, H; Zhang, Y; Fan, D; Pang, X; Du, Bin; Wei, Qin (2018) HERO ID: 4391887

[Less] In this work, a label-free electrochemical immunosensor was developed for the quantitative detection . . . [More] In this work, a label-free electrochemical immunosensor was developed for the quantitative detection of carcinoembryonic antigen (CEA). Flower-like Ag/MoS2/rGO nanocomposites were employed as the signal amplification platform of the designed immunosensor for the first time. Due to the synergistic effect between molybdenum disulfide (MoS2), reduced graphene oxide (rGO) and Ag nanoparticles (NPs), Ag/MoS2/rGO nanocomposites could provide a high sensitivity for the label-free electrochemical immunosensor. The detection mechanism was based on the monitoring of the electrocatalytic current response change towards the reduction of hydrogen peroxide (H2O2) when immunoreaction occurred on the surface of the electrode modified with Ag/MoS2/rGO nanocomposites. Using amperometric i-t curve to record the electrocatalytic process, the proposed immunosensor achieved an ultrasensitive and specific detection of CEA with a low detection limit of 1.6 fg/mL. Under optimal conditions, the fabricated immunosensor exhibited acceptable reproducibility, selectivity and excellent stability. This designed immunosensor could provide an effective method in the clinical diagnosis of other tumor markers. (C) 2017 Published by Elsevier B.V.