Read by QxMD icon Read


Alireza Khataee, Ramin Hassandoost, Shima Rahim Pouran
The present paper reports the sonocatalytic activity of cerium-substituted-magnetite for removal of oxytetracycline (OTC). The catalyst was prepared through a chemical route (co-precipitation, Fe3-xCexO4) and a mechanical procedure (CeO2/Fe3O4). Subsequently, the physico-chemical characteristics of both samples were determined using XRD, BET, SEM, EDX, TEM, Dot-mapping, FT-IR, DRS, and VSM analysis and compared to pristine magnetite and ceria. Afterwards, the effects of various operational conditions were assessed on sonocatalytic performance of Fe2...
March 2018: Ultrasonics Sonochemistry
T P Shende, B A Bhanvase, A P Rathod, D V Pinjari, S H Sonawane
The present work deals with the preparation of graphene oxide (GO) using Hummers-Offeman method in the presence of ultrasonic irradiations. Further loading of TiO2 photocatalyst on prepared GO was accomplished which is basically oxidation reduction reaction between graphene oxide and titanium isopropoxide that leads to the formation of graphene-TiO2 nanocomposite. Graphene-Ce-TiO2 and Graphene-Fe-TiO2 nanocomposites were prepared using one step in-situ ultrasound assisted method using GO, titanium isopropoxide, cerium nitrate, ferric nitrate, and 2-propanol...
March 2018: Ultrasonics Sonochemistry
Zhu Chen, Coleman X Kronawitter, Xiaofang Yang, Yao-Wen Yeh, Nan Yao, Bruce E Koel
A new catalyst is presented for the oxygen evolution reaction (OER) based on cerium-modified copper oxide (CuOx) prepared using a facile electrodeposition procedure. Incorporation of Ce into CuOx leads to greatly improved OER activity, which reached an optimal value at a surface concentration of 6.9 at% Ce. Specifically, the OER current density at 400 mV overpotential for the most active Ce-modified CuOx catalyst (6.9 at% Ce) was 3.3 times greater compared to the pure CuOx. Coincident with the improved OER activity, Ce incorporation also leads to significant structural changes that manifested in increasing degrees of disorder...
November 14, 2017: Physical Chemistry Chemical Physics: PCCP
Xiaogang Qu, Yuhuan Sun, Chuanqi Zhao, Nan Gao, Jinsong Ren
Stereoselectivity towards substrate is one of the most important characteristics of enzymes. Amino acids, as cofactors of many enzymes, play important roles in stereochemistry. Herein, chiral nanozymes were constructed by grafting a series of D- or L-amino acids on surfaces of ceria (cerium oxide) nanoparticles. We selected the most commonly used drug for combating Parkinson's disease 3, 4-dihydroxyphenylalanine (DOPA) enantiomers as examples for chiral catalysis. Through detailed kinetic studies of eight amino acids modified cerium oxide nanoparticles (CeNP), we found that phenylalanine-modified CeNP was optimal for the DOPA oxidation reaction and showed excellent stereoselectivity towards its enantiomers...
November 12, 2017: Chemistry: a European Journal
Kylie J Mitchell, Khalil A Abboud, George Christou
Synthesis of truly monodisperse nanoparticles and their structural characterization to atomic precision are important challenges in nanoscience. Success has recently been achieved for metal nanoparticles, particularly Au, with diameters up to 3 nm, the size regime referred to as nanoclusters. In contrast, families of atomically precise metal oxide nanoparticles are currently lacking, but would have a major impact since metal oxides are of widespread importance for their magnetic, catalytic and other properties...
November 13, 2017: Nature Communications
Chengli Zhang, Junlin He, Yuchan Zhang, Jun Chen, Yilin Zhao, Yazhen Niu, Chao Yu
The disposition dose of clopidogrel is different in CYP2C19*2 gene carriers and non-carriers. High-dose clopidogrel has been recommended to overcome a low-responsiveness to clopidogrel in patients with the CYP2C19*2 gene. To guide the choice of clopidogrel dosage and catalyse a development in the field of personalized therapy, we developed an ultrasensitive electrochemical biosensor to detect CYP2C19*2 gene. We constructed a novel assay based on cerium dioxide (CeO2)-functionalized carboxyl fullerene (c-C60) supported by Pt nanoparticles (c-C60/CeO2/PtNPs) for signal amplification...
November 8, 2017: Biosensors & Bioelectronics
Mahmoud A Omar, Kalid M Badr El-Din, Hesham Salem, Osama H Abdelmageed
Two simple and sensitive spectrophotometric and spectrofluorimetric methods for the determination of terbutaline sulfate, fenoterol hydrobromide, etilefrine hydrochloride, isoxsuprine hydrochloride, ethamsylate, doxycycline hyclate have been developed. Both methods were based on the oxidation of the cited drugs with cerium (IV) in acid medium. The spectrophotometric method was based on measurement of the absorbance difference (ΔA), which represents the excess cerium (IV), at 317nm for each drug. On the other hand, the spectrofluorimetric method was based on measurement of the fluorescent of the produced cerium (III) at emission wavelength 354nm (λexcitation=255nm) for the concentrations studied for each drug...
November 8, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Frank R Field, Timothy J Wallington, Mark P Everson, Randolph E Kirchain
A comprehensive component-level assessment of several strategic and minor metals (SaMMs) including copper, manganese, magnesium, nickel, tin, niobium, light rare earth elements (lanthanum, cerium, praseodymium, neodymium, promethium, and samarium), cobalt, silver, tungsten, heavy rare earth elements (yttrium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium) and gold use in the 2013 model year Ford Fiesta, Focus, Fusion, and F-150 is presented. Representative material contents in cars and light-duty trucks are estimated using comprehensive, component-level data reported by suppliers...
November 9, 2017: Environmental Science & Technology
Xiaorui Sun, Rulong Zhou, B Zhang
In literature, two different kinds of cerium atoms, namely Ce atoms with a localized 4f-electron and an iterant 4f-electron, have been suggested to coexist in low-density liquid cerium (A. Cadien et al., Phys. Rev. Lett., 2013, 110, 125503). However, direct evidence of this phenomenon is hard to be detected in the laboratory or classical MD simulations. Thus, the amazing properties of liquid cerium cannot be revealed. Herein, we have shown an ab initio MD simulation evidence that both kinds of cerium atoms can be detected in low-density liquid cerium at 13 GPa and 1900 K...
November 8, 2017: Physical Chemistry Chemical Physics: PCCP
Jamie L Marsh, Ashley E Wayman, Nicole M Smiddy, Dean J Campbell, John C Parker, Wayne B Bosma, Edward E Remsen
Surface adsorption of a homologous series of pyridine carboxylic acids on a hydrated colloidal cerium dioxide (ceria) film is characterized using the combination of experimental and computationally determined infrared (IR) spectra. Experimental analyses employ attenuated total reflectance (ATR) IR spectroscopy of deposited colloidal ceria thin films equilibrated with three pyridine carboxylic acids at pH 3.0, 5.5, and 8.5. The corresponding computational IR spectra for the energy-minimized intermediate and base forms of the pyridine carboxylic acids use density functional theory calculations at the B3LYP/6-311++G** level of theory...
November 7, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Sahadevan Rajesh, Steven Schneiderman, Caitlin Crandall, Hao Fong, Todd J Menkhaus
Fabrication of membrane adsorbers with elevated binding capacity and high throughput is highly desired for simplifying and improving purification efficiencies of bioproducts (biotherapeutics, vaccines, etc.) in the biotechnological and biopharmaceutical industries. Here we demonstrate the preparation of a novel class of self-supported, cellulose-graft-polypropionic acid (CL-g-PPA) cation-exchange nanofiber membrane adsorbers under mild reaction conditions for the purification of positively charged therapeutic proteins...
November 13, 2017: ACS Applied Materials & Interfaces
Shan Gao, Tiantian Luo, Qi Zhou, Wenjun Luo
In this study, by using heterogeneous esterification reaction and UV photo-induced technology, dendritic polyacrylic acid (PAA) was successfully grafted on to the surface of pinewood sawdust (PSD) particles to be used as an adsorbent and recovery medium for Ce(3+) from wastewater. 18 alkyl acid (stearic acid, SA), as a pre-modifier, was grafted onto the PSD surface. The outcome was the replacement of hydroxyl groups by hydrocarbon chains. Therefore, rich hydrogen atoms of the hydrocarbon chains on the PSD particles became sites whom can be taken away by photosensitizer molecules to form surface radicals...
September 8, 2017: Journal of Colloid and Interface Science
Honghong Wu, Nicholas Tito, Juan Pablo Giraldo
Plant abiotic stress leads to accumulation of reactive oxygen species (ROS) and a consequent decrease in photosynthetic performance. We demonstrate that a plant nanobionics approach of localizing negatively charged, sub-11 nm, spherical cerium oxide nanoparticles (nanoceria) inside chloroplasts in vivo augments ROS scavenging and photosynthesis of Arabidopsis thaliana plants under excess light (2000 µmol m-2 s-1, 1.5 h), heat (35 °C, 2.5 h), and dark chilling (4 °C, 5 days). Poly (acrylic acid) nanoceria (PNC) with a hydrodynamic diameter (10...
November 3, 2017: ACS Nano
Xiaofeng Wang, Ye Jin, Xinhua Liang
Different cycles (10-80) of CeO2 were coated on TiO2 nanoparticles by atomic layer deposition (ALD) using tris(ipropylcyclopentadienyl)cerium and de-ionized water as precursors at 250 ºC in a fluidized bed reactor. XRD analysis showed that TiO2 kept anatase structure after CeO2 ALD. With an increase in the number of ALD coating cycles, both photoluminescence (PL) intensity and band gap of the samples continuously decreased. The photocatalytic activity was evaluated based on the degradation of methylene blue (MB) solution under UV light...
November 3, 2017: Nanotechnology
S Grieshammer, M Martin
Defects and their interactions play a crucial role for the properties of solid state materials. While energies of defect formation and defect interaction are commonly calculated from first principles, calculations of corresponding vibrational entropies in solids are less common due to the high computational demand. This is in particular true for defect pairs as the existence of multiple defects lowers the symmetry of the cell. Here, we determine the entropies of association of defects in doped cerium oxide by density functional theory and phonon calculations...
November 8, 2017: Physical Chemistry Chemical Physics: PCCP
Zhiming Cao, Lorenzo Rossi, Cheyenne Stowers, Weilan Zhang, Leonardo Lombardini, Xingmao Ma
The ongoing global climate change raises concerns over the decreasing moisture content in agricultural soils. Our research investigated the physiological impact of two types of cerium oxide nanoparticles (CeO2NPs) on soybean at different moisture content levels. One CeO2NP was positively charged on the surface and the other negatively charged due to the polyvinylpyrrolidone (PVP) coating. The results suggest that the effect of CeO2NPs on plant photosynthesis and water use efficiency (WUE) was dependent upon the soil moisture content...
October 26, 2017: Environmental Science and Pollution Research International
Tomoo Mizugaki, Keito Togo, Zen Maeno, Takato Mitsudome, Koichiro Jitsukawa, Kiyotomi Kaneda
Highly selective hydrogenative carbon-carbon bond scission of biomass-derived platform oxygenates was achieved with a cerium oxide-supported ruthenium nanoparticle catalyst in water. The present catalyst enabled the selective cleavage of carbon-carbon σ bonds adjacent to carboxyl, ester, and hydroxymethyl groups, opening new eight synthetic routes to valuable chemicals from biomass derivatives. The high selectivity for such carbon-carbon bond scission over carbon-oxygen bonds was attributed to the multiple catalytic roles of the Ru nanoparticles assisted by the in situ formed Ce(OH)3...
October 25, 2017: Scientific Reports
Ragnar Hultborn
OBJECTIVE: To study blood flow, vascular volume and arterio-venous passages in induced mammary tumours of the rat to characterize parameters possibly responsible for tumour hyponutrition. METHOD: Dimethylbenzanthracene-induced mammary tumours in Sprague-Dawley rats were studied. Regional blood flow was studied by use of the radioactive microsphere tracer technique using (141)Cerium-labelled 15μm spheres coinjected into the left cardiac ventricle with (125)Iodine-labelled 25μm spheres...
October 22, 2017: Microvascular Research
Hajar Salehi, Abdolkarim Chehregani, Luigi Lucini, Ahmad Majd, Mansour Gholami
Chemically synthesized nanoparticles (NPs) are widely used in industry and concern over their impact on the environment is rising. In this study, greenhouse grown bean (Phaseolus vulgaris L.) plants were treated with CeO2 NPs suspensions at 0, 250, 500, 1000, and 2000mgL(-1) either aerially by spraying or via soil application. At 15days after treatment, plants were analyzed for Ce uptake, morphological and biochemical assays, as well as high-resolution mass spectrometry based metabolomics and proteomics. The results from ICP-MS assays showed a dose dependent absorption, uptake and translocation of Ce through both roots and leaves; Ce content increased from 0...
October 21, 2017: Science of the Total Environment
Jochen Friedrich, Cäcilia Maichle-Mössmer, Reiner Anwander
Metathesis reactions involving cerium(iv) complexes are generally hampered by a high tendency for reduction to the favoured trivalent state and a preference for ligand redistribution. Heteroleptic ceric Ce[OSi(OtBu)3]3Cl(thf) is easily obtained from the oxidation of Ce[OSi(OtBu)3]3(thf)2 with trityl chloride, while the absence of thf triggers formation of homoleptic Ce[OSi(OtBu)3]4. Ce[OSi(OtBu)3]3Cl(thf) engages in salt metathesis reactions with the alkali metal alkoxides KOCH3 and KOtBu, forming Ce[OSi(OtBu)3]3(OR)(thf)x, but experiences an extensive reductive ligand redistribution with the methylating agent ZnMe2...
October 24, 2017: Chemical Communications: Chem Comm
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"