Read by QxMD icon Read

Metal on metal

Zhen-Zhen Cao, Mei-Ling Qin, Xiao-Yan Lin, Zhi-Wei Zhu, Ming-Xue Chen
Sulfur (S) fertilizer application in rice (Oryza sativa L.) is crucial in determining rice grain productivity and quality. However, little information is available concerning the effect of S supply on cadmium (Cd) uptake and translocation in rice. In this study, both hydroponic and soil experiments were conducted to investigate the influence of S supply on Cd accumulation in rice under two Cd levels (0 and 50 μM), combined with three S concentrations (0, 2.64 and 5.28 mM). The moderate and excessive S supply (2...
March 13, 2018: Environmental Pollution
Giorgio Vilardi, Thanasis Mpouras, Dimitris Dermatas, Nicola Verdone, Angeliki Polydera, Luca Di Palma
Carbon Nanotubes (CNTs) and nano Zero-Valent Iron (nZVI) particles, as well as two nanocomposites based on these novel nanomaterials, were employed as nano-adsorbents for the removal of hexavalent chromium, selenium and cobalt, from aqueous solutions. Nanomaterials characterization included the determination of their point of zero charge and particle size distribution. CNTs were further analyzed using scanning electron microscopy, thermogravimetric analysis and Raman spectroscopy to determine their morphology and structural properties...
March 5, 2018: Chemosphere
María S Islas, Juan J Martínez Medina, Oscar E Piro, Gustavo A Echeverría, Evelina G Ferrer, Patricia A M Williams
Coumarins (2H-chromen-2-one) are oxygen-containing heterocyclic compounds that belong to the benzopyranones family. In this work we have synthesized different coordination complexes with coumarin-3-carboxylic acid (HCCA), o-phenanthroline (phen) and zinc(II). In the reported [Zn(CCA)2 (H2 O)2 ] complex, coumarin-3-carboxylate (CCA) is acting as a bidentate ligand while in the two prepared complexes, [Zn(phen)3 ]CCA(NO3 ) (obtained as a single crystal) and [Zn(CCA)2 phen].4H2 O, CCA is acting as a counterion of the complex cation [Zn(phen)3 ]+2 or coordinated to the metal center along with phen, respectively...
March 7, 2018: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Hamid Reza Rajabi, Fatemeh Karimi, Hossein Kazemdehdashti, Leila Kavoshi
In this research, a sono-assisted chemical precipitation method was developed for a quick and efficient water-based synthesis of zinc sulfide (ZnS) quantum dots (QDs), in room temperature. ZnS QDs as pure and doped with some transition metal ions (such as Cu2+ , Mn2+ , Ag+ ) were prepared in the presence of l-cysteine, as capping agent. In comparison with the previous conventional methods, applying the ultrasonic irradiation provides a significant decrease in the reaction time. In comparison with previous reported conventional chemical QD synthesis methods, the required time for a complete synthesis in the presence of ultrasonic irradiations was significantly reduced to a period as short as 15 min, in a temperature of 40 °C...
February 22, 2018: Journal of Photochemistry and Photobiology. B, Biology
Yaxin Qin, Guiying Li, Yanpeng Gao, Lizhi Zhang, Yong Sik Ok, Taicheng An
With the increased concentrations and kinds of refractory organic contaminants (ROCs) in aquatic environments, many previous reviews systematically summarized the applications of carbon-based materials in the adsorption and catalytic degradation of ROCs for their economically viable and environmentally friendly behavior. Interestingly, recent studies indicated that carbon-based materials in natural environment can also mediate the transformation of ROCs directly or indirectly due to their abundant persistent free radicals (PFRs)...
March 9, 2018: Water Research
Fabrizia Caiazzo, Vittorio Alfieri
In the framework of Additive Manufacturing of metals, Directed Energy Deposition of steel powder over flat surfaces and edges has been investigated in this paper. The aims are the repair and overhaul of actual, worn-out, high price sensitive metal components. A full-factorial experimental plan has been arranged, the results have been discussed in terms of geometry, microhardness and thermal affection as functions of the main governing parameters, laser power, scanning speed and mass flow rate; dilution and catching efficiency have been evaluated as well to compare quality and effectiveness of the process under conditions of both flat and edge depositions...
March 16, 2018: Materials
Varun Chandra, Danielle Buck, Rahul Chakrabarti, Alan McNab
A 24-year-old woman presented with a 1-year history of gradually increasing pain on eye movements, worse on the right. She had a significant background of undergoing intracranial correction of orbital hypertelorism with internal fixation of the lateral orbital rims at the age of 6 years. Imaging was consistent with bilateral metallic foreign bodies from both lateral orbital rims protruding into the globes. The patient underwent removal of bilateral plates and screws, with a significant improvement of symptoms and ocular motility postoperatively...
March 14, 2018: Ophthalmic Plastic and Reconstructive Surgery
Brianne R O'Leary, Frederick K Houwen, Chase L Johnson, Bryan G Allen, James J Mezhir, Daniel J Berg, Joseph J Cullen, Douglas R Spitz
Gastric adenocarcinoma most often presents at an advanced stage and overall five-year survival of ∼30%. Pharmacological ascorbate (high-dose IV ascorbate) has been proposed as a promising nontoxic adjuvant to standard radio-chemotherapies in several cancer types. In the current study, pharmacological ascorbate (0.5-2 m M) caused a dose-dependent decrease (70-85% at 2 m M) in clonogenic survival of gastric adenocarcinoma cells (AGS and MNK-45), but was relatively nontoxic to a small intestinal epithelial nonimmortalized human cell isolate (FHs 74 Int)...
March 16, 2018: Radiation Research
Christopher E Patrick, Santosh Kumar, Geetha Balakrishnan, Rachel S Edwards, Martin R Lees, Leon Petit, Julie B Staunton
Magnetocrystalline anisotropy, the microscopic origin of permanent magnetism, is often explained in terms of ferromagnets. However, the best performing permanent magnets based on rare earths and transition metals (RE-TM) are in fact ferrimagnets, consisting of a number of magnetic sublattices. Here we show how a naive calculation of the magnetocrystalline anisotropy of the classic RE-TM ferrimagnet GdCo_{5} gives numbers that are too large at 0 K and exhibit the wrong temperature dependence. We solve this problem by introducing a first-principles approach to calculate temperature-dependent magnetization versus field (FPMVB) curves, mirroring the experiments actually used to determine the anisotropy...
March 2, 2018: Physical Review Letters
Yongxi Ou, D C Ralph, R A Buhrman
Robust spin Hall effects (SHE) have recently been observed in nonmagnetic heavy metal systems with strong spin-orbit interactions. These SHE are either attributed to an intrinsic band-structure effect or to extrinsic spin-dependent scattering from impurities, namely, side jump or skew scattering. Here we report on an extraordinarily strong spin Hall effect, attributable to spin fluctuations, in ferromagnetic Fe_{x}Pt_{1-x} alloys near their Curie point, tunable with x. This results in a dampinglike spin-orbit torque being exerted on an adjacent ferromagnetic layer that is strongly temperature dependent in this transition region, with a peak value that indicates a lower bound 0...
March 2, 2018: Physical Review Letters
Li-Hui Mou, Qing-Yu Liu, Ting Zhang, Zi-Yu Li, Sheng-Gui He
Dinitrogen activation/fixation is one of the most important and challenging subjects in synthetic as well as theoretical chemistry. In this study, the adsorption reactions of N2 onto TaCn - ( n = 1-4) cluster anions have been investigated by means of mass spectrometry in conjunction with density functional theory calculations. Following the experimental results that only TaC4 - was observed to adsorb N2 , theoretical calculations predicted that TaC4 - reaction system (TaC4 - + N2 → TaC4 N2 - ) has a negligible barrier on the approach of N2 molecule while insurmountable barriers are located on the reaction pathways of TaC1-3 - /N2 reaction systems...
March 16, 2018: Journal of Physical Chemistry. A
Rui Liu, Huimin Chen, Liping Fang, Cuihong Xu, Zuoliang He, Yujian Lai, Huachao Zhao, Deribachew Bekana Hirpa, Jing-Fu Liu
AuPd bimetallic nanocatalysts exhibit superior catalytic performance in the cleavage of carbon-halogen bonds (C-X) in the hazardous halogenated pollutants. A better understanding of how Au atoms promote the reactivity of Pd sites rather than vaguely interpreting as bimetallic effect, and determining which type of Pd sites are necessary for these reactions are crucial factors for the design of atomically precise nanocatalysts that make full use of both the Pd and Au atoms. Herein, we systematically manipulated the coordination number of Pd-Pd, d-orbital occupation state and Au-Pd interface of the Pd reactive centers, and studied the structure-activity relationship of Au-Pd in the catalyzed cleavage of C-X bonds...
March 16, 2018: Environmental Science & Technology
Debasis Banerjee, Xianyin Chen, Sergey Lobanov, Anna M Plonka, Xiaojun Chan, John Daly, Taejin Kim, Praveen K Thallapally, John Parise
Used nuclear fuel reprocessing represents a unique challenge when dealing with radionuclides such as isotopes of85 Kr and129 I2 due to their volatility and long half-life. Efficient capture of129 I2 (t1/2 = 15.7 ×106 million years) from the nuclear waste stream can help reduce the risk of releasing I2 radionuclide into the environment and/or potential incorporation into the human thyroid. Metal organic frameworks have the reported potential to be I2 adsorbents but the effect of water vapor, generally present in the reprocessing off-gas stream, is rarely taken into account...
March 16, 2018: ACS Applied Materials & Interfaces
Srabanti Ghosh, Laurence Ramos, Hynd Remita
Materials are the key roadblocks for the commercialization of energy conversion devices in fuel cells and solar cells. Significant research has focused on tuning the intrinsic properties of materials at the nanometer scale. The soft template mediated controlled fabrication of advanced nanostructured materials is attracting considerable interest due to the promising applications of these materials in catalysis and electrocatalysis. Swollen hexagonal lyotropic liquid crystals (SLCs) consist of oil-swollen surfactant-stabilized 1D, 2D or 3D nanometric assemblies regularly arranged in an aqueous solvent...
March 16, 2018: Nanoscale
Seiji Obata, Minoru Sato, Keishi Akada, Koichiro Saiki
A high throughput synthesis method of graphene has been required for a long time to apply graphene to industrial applications. Of the various synthesis methods, the chemical exfoliation of graphite via graphene oxide (GO) is advantageous as far as productivity is concerned; however, the quality of the graphene produced by this method is far inferior to that synthesized by other methods, such as chemical vapor deposition on metals. Developing an effective reduction and restoration method for GO on dielectric substrates has been therefore a key issue...
March 16, 2018: Nanotechnology
Jianfeng Zhang, Qunling Fang, Jinyu Duan, Hongmei Xu, Hua-Jian Xu, Shouhu Xuan
This work reports a novel Fe3O4@polydopamine-Au-polydopamine core/shell nanocomposite towards magnetically separable nanocatalyst. Because the polydopamine (PDA) layers sandwiched Au nanocrystals were prepared by a layer-by-layer method, the content of Au could be controlled by varying the Au shell number (such as burger-like Fe3O4@PDA/Au/PDA/Au/PDA). The Fe3O4@PDA/Au/PDA exhibited excellent catalytic activity on reducing the p-Nitrophenol since the substrate could penetrate the PDA shell. Owing to the protection of PDA shell, the Fe3O4@PDA/Au/PDA presented higher cyclability than the Fe3O4@PDA/Au...
March 16, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Si Xuan She, Jie Yu, Wan Qi Tang, Yinlong Zhu, Yu Bo Chen, Jaka Sunarso, Wei Zhou, Zongping Shao
Perovskite oxide is an attractive low-cost alternative catalyst for oxygen evolution reaction (OER) relative to the precious metal oxide-based eletrocatalysts (IrO2 and RuO2). In this work, a series of Sr-doped La-based perovskite oxide catalysts with compositions of La1-xSrxFeO3-δ (x = 0, 0.2, 0.5, 0.8, and 1) are synthesized and characterized. The OER specific activities in alkaline solution increase in the order of LaFeO3-δ (LF), La0.8Sr0.2FeO3-δ (LSF-0.2), La0.5Sr0.5FeO3-δ (LSF-0.5), SrFeO3-δ (SF) and La0...
March 16, 2018: ACS Applied Materials & Interfaces
Marius Andruh
This paper reviews the most representative examples of heterometallic complexes containing three different paramagnetic metal ions, focusing on their magnetic properties. These compounds show a rich structural variety, ranging from discrete species to coordination polymers of various dimensionalities. The general synthetic strategies leading to heterotrimetallic complexes are discussed and illustrated.
March 16, 2018: Chemical Communications: Chem Comm
Gaganpreet Kaur, Amanpreet Singh, Ajnesh Singh, Navneet Kaur, Narinder Singh
The unregulated use of organophosphates (OPs) as pesticides and toxic chemical warfare agents demands their continuous monitoring from a human health perspective. This study describes a fluorescence turn-on sensing assay for the selective quantification of OPs in aqueous medium. Metal complexes of two different Biginelli derivatives were processed in water through a reprecipitation technique. The engineered self-assembly of the pyridyl-2-cobalt complex (L1·Co(II)) was employed to selectively detect malathion while the pyridyl-4-cobalt complex (L2·Co(II)) could estimate azamethiphos fluorimetrically up to a detection limit of 9...
March 16, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Feiyang Yu, Ya Gao, Zhongling Lang, Yuanyuan Ma, Liying Yin, Jing Du, Huaqiao Tan, Yonghui Wang, Yangguang Li
Molybdenum carbides are considered as one type of privileged noble-metal-free electrocatalysts for hydrogen evolution reactions (HER) due to their d-band electron structure, which is similar to Pt. Especially, the electronic structure of such materials can be further adjusted by elemental doping to improve their electrocatalytic activity. Herein, we selected the Anderson-type polyoxometalates (POMs) (NH4)n[TMMo6O24H6]·5H2O (TM = Ni2+, Co2+, n = 4; TM = Fe3+, Cr3+, n = 3) as precursors to prepare new transition-metal-doped Mo2C materials...
March 16, 2018: Nanoscale
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"