keyword
MENU ▼
Read by QxMD icon Read
search

Metal

keyword
https://www.readbyqxmd.com/read/29334673/copper-bioaccumulation-and-biokinetic-modeling-in-marine-herbivorous-fish-siganus-oramin
#1
Yanyan Zhou, Fangsan Wei, Wei Zhang, Zhiqiang Guo, Li Zhang
Marine herbivorous fish directly consume macroalgae, which commonly accumulate high levels of trace metals in polluted areas. We proposed that herbivorous fish could be better candidates for biomonitoring marine metal pollution than carnivorous fish. To date, the trophic transfer of Cu from macroalgae to marine herbivorous fish is unclear. In this study, the kinetics of Cu bioaccumulation in a widespread marine herbivorous fish, Siganus oramin, were investigated, and biokinetic modeling was applied to estimate the Cu levels in the fish sampled from different sites and seasons...
January 10, 2018: Aquatic Toxicology
https://www.readbyqxmd.com/read/29334672/oxidative-and-interactive-challenge-of-cadmium-and-ocean-acidification-on-the-smooth-scallop-flexopecten-glaber
#2
Alessandro Nardi, Maura Benedetti, Daniele Fattorini, Francesco Regoli
Ocean acidification (OA) may affect sensitivity of marine organisms to metal pollution modulating chemical bioavailability, bioaccumulation and biological responsiveness of several cellular pathways. In this study, the smooth scallop Flexopecten glaber was exposed to various combinations of reduced pH (pH/pCO2 7.4/∼3000 μatm) and Cd (20 μg/L). The analyses on cadmium uptake were integrated with those of a wide battery of biomarkers including metallothioneins, single antioxidant defenses and total oxyradical scavenging capacity in digestive gland and gills, lysosomal membrane stability and onset of genotoxic damage in haemocytes...
January 8, 2018: Aquatic Toxicology
https://www.readbyqxmd.com/read/29334652/insight-into-the-expression-variation-of-metal-responsive-genes-in-the-seedling-of-date-palm-phoenix-dactylifera
#3
Zayneb Chaâbene, Agnieszka Rorat, Imen Rekik Hakim, Fabien Bernard, Grubb C Douglas, Amine Elleuch, Franck Vandenbulcke, Hafedh Mejdoub
Phytochelatin synthase and metallothionein gene expressions were monitored via qPCR in order to investigate the molecular mechanisms involved in Cd and Cr detoxification in date palm (Phoenix dactylifera). A specific reference gene validation procedure using BestKeeper, NormFinder and geNorm programs allowed selection of the three most stable reference genes in a context of Cd or Cr contamination among six reference gene candidates, namely elongation factor α1, actin, aldehyde dehydrogenase, SAND family, tubulin 6 and TaTa box binding protein...
December 28, 2017: Chemosphere
https://www.readbyqxmd.com/read/29334637/contamination-characteristics-and-source-apportionment-of-heavy-metals-in-topsoil-from-an-area-in-xi-an-city-china
#4
Xiuduan Chen, Xinwei Lu
As soil-extractable elements potentially pose ecological and health risks, identifying their contamination characteristics and sources is crucial. Therefore, to understand topsoil trace elements in the urban ring zone from the Second Ring Road to the Third Ring of Xi'an city in China, we determined the concentrations of Zn, Co, V, As, Cu, Mn, Ba, Ni and Pb, and analyzed the sources of the contamination. The results showed that the individual pollution indices of Pb, Co, Cu, Zn, Ba, Ni, Mn, As, and V were 1...
January 11, 2018: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/29334633/fluorous-assisted-metal-chelate-affinity-extraction-for-nucleotides-followed-by-hilic-ms-ms-analysis
#5
Ena Kiyokawa, Tadashi Hayama, Hideyuki Yoshida, Masatoshi Yamaguchi, Hitoshi Nohta
We herein developed a selective method for the determination of nucleotides by fluorous-assisted metal chelate affinity extraction followed by hydrophilic interaction liquid chromatography (HILIC) combined with tandem mass spectrometric (MS/MS) analysis. In this study, the nucleotides were selectively chelated by Fe(III)-immobilized perfluoroalkyliminodiacetic acid, and the resulting chelates were subsequently extracted into a fluorous solvent. The nucleotides present in the fluorous solvent were then back-extracted into a non-fluorous solution, such as a solution of ammonia in aqueous acetonitrile...
January 3, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29334454/aurophilic-interactions-in-l-au-x-%C3%A2-l-au-x-dimers-calibration-by-experiment-and-theory
#6
Erik Andris, Prokopis Andrikopoulos, Jiří Schulz, Jan Turek, Aleš Růžička, Jana Roithová, Lubomír Rulíšek
Attractive metallophilic (aurophilic, argentophilic, cuprophilic, …) interactions play an important role in arrangement and stabilization of oligonuclear metal ion complexes. We report a combined experimental and theoretical assessment of aurophilic interactions in closed-shell gold(I) dimers. The experimental binding energies were obtained for charged [(LH)AuCl]+…[(L')AuCl] dimers (L is either a phosphine or a N-heterocyclic carbene ligand) in the gas phase. These energies served for benchmarking of correlated quantum chemical calculations (CCSD(T)-calibrated SCS-MP2/CBS method) that were then applied to neutral [(L)AuX]…[(L')AuX] dimers (X = Cl, Br, I)...
January 15, 2018: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/29334396/towards-the-continuous-production-of-pt-based-heterogeneous-catalysts-using-microfluidic-systems
#7
Uson Laura, Manuel Arruebo, Victor Sebastian
The continuous production of Pt-based heterogeneous catalysts based on ultra-small (<2 nm) noble metal nanoparticles deposited on mesoporous ordered silica and their catalytic activity in VOC abatement are here reported. Microfluidic reactors can be used not only to enable the fast and controlled production of ultra-small Pt nanoparticles (NPs), but also alloyed NPs including PtPd, PtRu and PtRh can be formed in short residence times (between 60 s and 5 min). A novel continuous and homogeneous loading of these catalytic NPs on SBA-15 used as a mesoporous support is also here reported...
January 15, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/29334388/catalytic-de-hydrogenation-promoted-by-non-precious-metals-co-fe-and-mn-recent-advances-in-an-emerging-field
#8
REVIEW
Georgy A Filonenko, Robbert van Putten, Emiel J M Hensen, Evgeny A Pidko
Catalytic hydrogenation and dehydrogenation reactions form the core of the modern chemical industry. This vast class of reactions is found in any part of chemical synthesis starting from the milligram-scale exploratory organic chemistry to the multi-ton base chemicals production. Noble metal catalysis has long been the key driving force in enabling these transformations with carbonyl substrates and their nitrogen-containing counterparts. This review is aimed at introducing the reader to the remarkable progress made in the last three years in the development of base metal catalysts for hydrogenations and dehydrogenative transformations...
January 15, 2018: Chemical Society Reviews
https://www.readbyqxmd.com/read/29334362/investigation-of-resistance-switching-in-siox-rram-cells-using-a-3d-multi-scale-kinetic-monte-carlo-simulator
#9
Toufik Sadi, Adnan Mehonic, Luca Montesi, Mark Buckwell, Anthony Kenyon, Asen Asenov
We employ an advanced three-dimensional (3D) electro-thermal simulator to explore the physics and potential of oxide-based resistive random-access memory (RRAM) cells. The physical simulation model has been developed recently, and couples a kinetic Monte Carlo study of electron and ionic transport to the self-heating phenomenon while accounting carefully for the physics of vacancy generation and recombination, and trapping mechanisms. The simulation framework successfully captures resistance switching, including the electroforming, set and reset processes, by modeling the dynamics of conductive filaments in the 3D space...
January 15, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/29334298/long-term-effects-of-tungsten-carbide-wc-nanoparticles-in-pelagic-and-benthic-aquatic-ecosystems
#10
Mikael T Ekvall, Jonas Hedberg, Inger Odnevall Wallinder, Lars-Anders Hansson, Tommy Cedervall
As the production and usage of nanomaterials are increasing so are the concerns related to the release of the material into nature. Tungsten carbide (WC) is widely used for its hard metal properties, although its use, in for instance tyre studs, may result in nano-sized particles ending up in nature. Here, we evaluate the potential long-term exposure effects of WC nanoparticles on a pelagic (Daphnia magna) and a benthic (Asellus aquaticus) organism. No long-term effects were observed in the benthic system with respect to population dynamics or ecosystem services...
January 15, 2018: Nanotoxicology
https://www.readbyqxmd.com/read/29334224/diversity-oriented-approach-to-n-heterocyclic-compounds-from-%C3%AE-phenyl-%C3%AE-enamino-ester-via-a-mitsunobu-michael-reaction-sequence
#11
Hina P A Khan, Tushar Kanti Chakraborty
Herein we delineate a novel route for the diastereoselective construction of diversely substituted N-heterocyclic ring systems as valuable scaffolds for natural products and pharmaceuticals, starting from easily accessible prochiral α-phenyl-β-enamino ester. The reaction sequence relies on the unexplored reactivity of α-phenyl-β-enamino ester as a nucleophilic partner in Mitsunobu reaction to forge the N-tethered alkene-alcohol/thiol/amine intermediate which was subjected to intramolecular hetero-Michael addition reaction under mild conditions to furnish the respective N-heterocyclic compounds embedded with an exocyclic chiral center in high yields and excellent diastereoselectivities...
January 15, 2018: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/29334159/a-gold-iii-pincer-ligand-scaffold-for-the-synthesis-of-binuclear-and-bioconjugated-complexes-synthesis-and-anticancer-potential
#12
Bertrand Benoît, Maria A O'Connell, Zöe A E Waller, Manfred Bochmann
Cyclometalated (C^N^C)Au(III) complexes bearing functionalized N-heterocyclic carbene (NHC) ligands provide a high-yielding, modular route to bioconjugated and binuclear complexes. That methodology has been applied to the synthesis of bioconjugated complexes presenting biotin and 17α-ethynylestradiol vectors, as well as to the synthesis of bimetallic Au(III)/Au(I) complexes. The in vitro antiproliferative activities of these compounds against various cancer cells lines depend on the linker length, with the longer linker being the most potent...
January 15, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29334153/heterobimetallic-complexes-for-theranostic-applications
#13
M Concepción Gimeno, Vanesa Fernández-Moreira
The design of more efficient anticancer drugs requires a deeper understanding of their biodistribution and mechanism of action. Cell imaging agents could help to gain insight into biological processes and, consequently, the best strategy for attaining suitable scaffolds in which both, biological and imaging properties are maximized. A new concept arises in this field which is the combination of two metal fragments as collaborative partners to provide the precise emissive properties to visualize the cell as well as the optimum cytotoxic activity to build more potent and selective chemotherapeutic agents...
January 15, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29334152/dynamic-coordination-of-eu-iminodiacetate-to-control-fluorochromic-response-of-polymer-hydrogels-to-multistimuli
#14
Gengsheng Weng, Srinivas Thanneeru, Jie He
New fluorochromic materials that reversibly change their emission properties in response to their environment are of interest for the development of sensors and light-emitting materials. A new design of Eu-containing polymer hydrogels showing fast self-healing and tunable fluorochromic properties in response to five different stimuli, including pH, temperature, metal ions, sonication, and force, is reported. The polymer hydrogels are fabricated using Eu-iminodiacetate (IDA) coordination in a hydrophilic poly(N,N-dimethylacrylamide) matrix...
January 15, 2018: Advanced Materials
https://www.readbyqxmd.com/read/29334150/a-general-method-for-the-chemical-synthesis-of-large-scale-seamless-transition-metal-dichalcogenide-electronics
#15
Li Li, Yichuan Guo, Yuping Sun, Long Yang, Liang Qin, Shouliang Guan, Jinfen Wang, Xiaohui Qiu, Hongbian Li, Yuanyuan Shang, Ying Fang
The capability to directly build atomically thin transition metal dichalcogenide (TMD) devices by chemical synthesis offers important opportunities to achieve large-scale electronics and optoelectronics with seamless interfaces. Here, a general approach for the chemical synthesis of a variety of TMD (e.g., MoS2 , WS2 , and MoSe2 ) device arrays over large areas is reported. During chemical vapor deposition, semiconducting TMD channels and metallic TMD/carbon nanotube (CNT) hybrid electrodes are simultaneously formed on CNT-patterned substrate, and then coalesce into seamless devices...
January 15, 2018: Advanced Materials
https://www.readbyqxmd.com/read/29334147/uniform-lithium-nucleation-growth-induced-by-lightweight-nitrogen-doped-graphitic-carbon-foams-for-high-performance-lithium-metal-anodes
#16
Lin Liu, Ya-Xia Yin, Jin-Yi Li, Shu-Hua Wang, Yu-Guo Guo, Li-Jun Wan
The lithium metal anode has attracted soaring attention as an ideal battery anode. Unfortunately, nonuniform Li nucleation results in uncontrollable growth of dendritic Li, which incurs serious safety issues and poor electrochemical performance, hindering its practical applications. Herein, this study shows that uniform Li nucleation/growth can be induced by an ultralight 3D current collector consisting of in situ nitrogen-doped graphitic carbon foams (NGCFs) to realize suppressing dendritic Li growth at the nucleating stage...
January 15, 2018: Advanced Materials
https://www.readbyqxmd.com/read/29334145/colloidal-cobalt-phosphide-nanocrystals-as-trifunctional-electrocatalysts-for-overall-water-splitting-powered-by-a-zinc-air-battery
#17
Hui Li, Qi Li, Peng Wen, Trey B Williams, Shiba Adhikari, Chaochao Dun, Chang Lu, Dominique Itanze, Lin Jiang, David L Carroll, George L Donati, Pamela M Lundin, Yejun Qiu, Scott M Geyer
Highly efficient and stable electrocatalysts, particularly those that are capable of multifunctionality in the same electrolyte, are in high demand for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). In this work, highly monodisperse CoP and Co2 P nanocrystals (NCs) are synthesized using a robust solution-phase method. The highly exposed (211) crystal plane and abundant surface phosphide atoms make the CoP NCs efficient catalysts toward ORR and HER, while metal-rich Co2 P NCs show higher OER performance owing to easier formation of plentiful Co2 P@COOH heterojunctions...
January 15, 2018: Advanced Materials
https://www.readbyqxmd.com/read/29334130/radiofrequency-ablation-combined-with-multiple-biliary-metal-stent-placement-using-short-type-single-balloon-endoscope-in-patients-with-surgically-altered-anatomy
#18
Tadahisa Inoue, Kiyoaki Ito, Masashi Yoneda
Placement of multiple metal stents (MS) for the management of high-grade malignant hilar biliary obstruction (MHBO) is useful,1,2 and biliary radiofrequency ablation (RFA) has been suggested to improve stent patency.3,4 However, to our knowledge, there are no reports of RFA procedures performed using a single-balloon endoscope (SBE) in patients with surgically altered anatomy. Here, we report a successful case of RFA combined with multiple MS placement using SBE in Roux-en-Y gastrectomy. This article is protected by copyright...
January 15, 2018: Digestive Endoscopy: Official Journal of the Japan Gastroenterological Endoscopy Society
https://www.readbyqxmd.com/read/29334111/constructing-two-dimensional-cufese2-au-heterostructured-nanosheets-with-an-amorphous-core-and-a-crystalline-shell-for-enhanced-near-infrared-light-water-oxidation
#19
Huang Wen, Hua Li, Suisui He, Fengjuan Chen, Erli Ding, Sha Liu, Baodui Wang, Yong Peng
Although substantial efforts have been made toward the synthesis of noble metal-semiconductor heteronanostructures, direct in situ synthesis of two-dimensional (2D) core-shell semiconductor@noble metal heterostructured nanosheets remains largely unexplored. Herein, we report the synthesis of a novel 2D core-shell CuFeSe2@Au heterostructured nanosheet with an amorphous core and a crystalline shell based on the reversed growth of Au nanosheets on the CuFeSe2 frameworks under near-infrared (NIR) illumination. The nanosheet exhibits strong absorbance in the NIR region, and the valence band top of CuFeSe2@Au nanosheets is higher than the oxidation potential of O2/H2O...
January 15, 2018: Nanoscale
https://www.readbyqxmd.com/read/29334104/one-pot-cascade-synthesis-of-azabicycles-via-the-nitro-mannich-reaction-and-n-alkylation
#20
Wannaporn Disadee, Somsak Ruchirawat
A one-pot, metal-free process for the synthesis of azabicycles is developed. The key transformations involved a cascade of double intramolecular cyclizations via the nitro-Mannich reaction and N-alkylation, providing various ring systems of azabicycles in yields up to 81% and an isomeric ratio of 62 : 1. This approach offers considerable advantages in terms of the handling of small molecules, the flexibility to introduce a functionalized side chain, and gives direct access to various azabicycles.
January 15, 2018: Organic & Biomolecular Chemistry
keyword
keyword
31523
1
2
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"