Read by QxMD icon Read

acid base strong ion

Prabhat K Upadhyay, Sreekar B Marpu, Erin N Benton, Corshai L Williams, Ameya Telang, Mohammad A Omary
We report a phosphorescent chemosensor based on a trinuclear Au(I) pyrazolate complex or [Au(3-CH3,5-COOH)Pz]3, (aka Au3Pz3) stabilized in aqueous chitosan (CS) polymer media. Au3Pz3 is synthesized in situ within aqueous CS media at pH ~ 6.5 and room temperature (RT). Au3Pz3 exhibits strong red emission (λmax ~690 nm) in such solutions. The Au3Pz3 emission is found to be sensitive to sub-ppm/nM levels of silver ions. On addition of silver salt to Au3Pz3/CS aqueous media, a bright-green emissive adduct (Au3Pz3/Ag+) with peak maximum within 475-515 nm is developed...
January 17, 2018: Analytical Chemistry
Hui Zhao, Yang Wei, Cheng Wang, Rui-Min Qiao, Wanli Yang, Phillip B Messersmith, Gao Liu
The excessive volume changes during cell cycling of Si-based anode in lithium ion batteries impeded its application. One major reason for the cell failure is particle isolation during volume shrinkage in delithiation process, which makes strong adhesion between polymer binder and anode active material particles a highly desirable property. Here, a biomimetic side-chain conductive polymer incorporating catechol, a key adhesive component of the mussel holdfast protein, was synthesized. Atomic force microscopy (AFM) based single molecule force measurements of mussel-inspired conductive polymer binder contacting a silica surface revealed similar adhesion toward substrate when compared with an effective Si anode binder, homo-polyacrylic acid (PAA), with the added benefit of being electronically conductive...
January 15, 2018: ACS Applied Materials & Interfaces
J A Kiernan
Previous investigators have disagreed about whether hemalum stains DNA or its associated nucleoproteins. I review here the literature and describe new experiments in an attempt to resolve the controversy. Hemalum solutions, which contain aluminum ions and hematein, are routinely used to stain nuclei. A solution containing 16 Al3+ ions for each hematein molecule, at pH 2.0-2.5, provides selective progressive staining of chromatin without cytoplasmic or extracellular "background color." Such solutions contain a red cationic dye-metal complex and an excess of Al3+ ions...
January 11, 2018: Biotechnic & Histochemistry: Official Publication of the Biological Stain Commission
Jeremy A Nowak, Pravin Malla Shrestha, Robert Jay Weber, Amy M McKenna, Huan Chen, John D Coates, Allen H Goldstein
Biosouring in crude oil reservoirs by sulfate-reducing microbial communities (SRCs) results in hydrogen sulfide production, precipitation of metal sulfide complexes, increased industrial costs of petroleum production, and exposure issues for personnel. Potential treatment strategies include nitrate or perchlorate injections into reservoirs. Gas chromatography with vacuum ultraviolet ionization and high-resolution time-of-flight mass spectrometry (GC-VUV-HTOF) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) combined with electrospray ionization were applied in this study to identify hydrocarbon degradation patterns and product formations in crude oil samples from biosoured, nitrate treated, and perchlorate treated bioreactor column experiments...
January 10, 2018: Environmental Science & Technology
A Choube, M Astekar, A Choube, G Sapra, A Agarwal, A Rana
Teeth are among the hardest animal tissues, because they are composed of large amounts of inorganic compounds. Consequently, teeth are difficult to prepare for microscopic examination. Acids and chelating agents traditionally have been used to remove calcium ions. We compared decalcifying agents including strong acids, weak acids, chelating agents, techniques using electric current, agitation and heat. Freshly extracted teeth were fixed and decalcified using formic acid-formalin, formal-nitric acid, formalin-EDTA, Von Ebner's fluid and Perenyi's fluid...
January 9, 2018: Biotechnic & Histochemistry: Official Publication of the Biological Stain Commission
Fumihiko Ogata, Mikako Obayashi, Eri Nagahashi, Takehiro Nakamura, Naohito Kawasaki
In this study, we prepared calcium silicate at different molar ratios (Ca:Si=1:3, 1:6, and 1:9 refer to CAS-30S, CAS-60S, and CAS-90S, respectively) with water addition. The adsorbent characteristics (specific surface area, pore volume, mean pore diameter, and elemental analysis) were measured and the effect of water addition on the adsorbent surface for the prevention of deterioration was evaluated. In addition, the deterioration of soybean oil (SO) subjected to heating and aeration was investigated based on the acid value (AV) and carbonyl value (CV)...
2018: Journal of Oleo Science
Sujay S Kaushal, Gene E Likens, Michael L Pace, Ryan M Utz, Shahan Haq, Julia Gorman, Melissa Grese
Salt pollution and human-accelerated weathering are shifting the chemical composition of major ions in fresh water and increasing salinization and alkalinization across North America. We propose a concept, the freshwater salinization syndrome, which links salinization and alkalinization processes. This syndrome manifests as concurrent trends in specific conductance, pH, alkalinity, and base cations. Although individual trends can vary in strength, changes in salinization and alkalinization have affected 37% and 90%, respectively, of the drainage area of the contiguous United States over the past century...
January 8, 2018: Proceedings of the National Academy of Sciences of the United States of America
Shaogang Chu, Robert J Letcher
While reversed-phase (RP) liquid chromatography can separate a wide range of analytes, for strongly acidic compounds such as environmentally relevant dialkyl phosphates (DAPs), this remains a challenge because they have low affinity for standard RP columns or they exhibit inferior peak shapes. Mixed-mode chromatographic (MMC) columns, which contain both RP and ion-exchange functionalities, can address these resolution problems. However, using current MMC separation approaches, analyte peaks are relatively broad as compared to conventional RP chromatography...
January 2, 2018: Journal of Chromatography. A
Catherine Foulon, Pauline Di Giulio, Marie Lecoeur
Supercritical fluid chromatography (SFC) is commonly used for the analysis of non-polar compounds, but remains poorly explored for the separation of polar and ionized molecules. In this paper, SFC has been investigated for the separation of 14 inorganic ions sampled in aqueous solutions. Four polar stationary phases were first screened using CO2-methanol-based mobile phases containing water or different acidic or basic additives, in order to select the most efficient conditions for the simultaneous retention of inorganic cations and anions and to favor their detection using evaporative light scattering detector (ELSD)...
December 18, 2017: Journal of Chromatography. A
Olga Gorlova, Stephanie M Craig, Mark A Johnson
To unravel the intermolecular interactions at play in the assemblies of EMIM-based ionic liquids, we report the vibrational spectra of the cryogenically cooled, cationic ternary complexes with halide ions, (EMIM+)2X-, X = Cl, Br, and I. This series specifically addresses the spectral response of the acidic C(2)H group upon complexation with an atomic anion, which is isolated by selective deuteration at this position. Unlike the behavior of the related BF4- complex, the halide systems display large (∼175 cm-1) red-shifts and dramatic (∼30X) intensity enhancements in the C(2)D stretch (relative to that of the bare d(2)-EMIM+ cation), which are largest for the chloride anion...
December 21, 2017: Journal of Chemical Physics
B Nozière, F Fache, A Maxut, B Fenet, A Baudouin, L Fine, C Ferronato
Naturally-occurring inorganic ammonium ions have been recently reported as efficient catalysts for some organic reactions in water, which contributes to the understanding of the chemistry in some natural environments (soils, seawater, atmospheric aerosols, …) and biological systems, and is also potentially interesting for green chemistry as many of their salts are cheap and non-toxic. In this work, the effect of NH4+ ions on the hydrolysis of small epoxides in water was studied kinetically. The presence of NH4+ increased the hydrolysis rate by a factor of 6 to 25 compared to pure water and these catalytic effects were shown not to result from other ions, counter-ions or from acid or base catalysis, general or specific...
December 20, 2017: Physical Chemistry Chemical Physics: PCCP
Nicholas M Schneider, Jeung Hun Park, Joseph M Grogan, Daniel A Steingart, Haim H Bau, Frances M Ross
Control of interfacial morphology in electrochemical processes is essential for applications ranging from nanomanufacturing to batteries. Here, we quantify the evolution of an electrochemical growth front, using liquid cell electron microscopy to access unexplored length and time scales. During galvanostatic deposition of copper from an acidic electrolyte, we find that the growth front initially evolves consistent with kinetic roughening theory. Subsequently, it roughens more rapidly, consistent with diffusion-limited growth physics...
December 19, 2017: Nature Communications
Tibor Sopcak, Lubomir Medvecky, Maria Giretova, Radoslava Stulajterova, Juraj Durisin
Bone cements based on magnesium phosphates such as newberyite (N; MgHPO4.3H2O) have been shown as potential bone substitutes due to their biocompatibility, biodegradability and ability to support osteoblast differentiation and proliferation. Newberyite can hydrolyze to hydrated magnesium phosphate compounds (e.g. bobierite (Mg3(PO4)2.8H2O)) at alkaline conditions. In this study, 25 and 50 wt% of crystalline β -wollastonite (woll; CaSiO3) was admixed to newberyite powder in order to both enhance the acid-base hydrolysis of newberyite and to produce a functional bone cement...
January 1, 2017: Journal of Biomaterials Applications
José A Murillo Pulgarín, Aurelia Alañón Molina, Elisa Jiménez García
A new chemiluminescence (CL) detection system combined with flow injection analysis (FIA) for the determination of Pefloxacin is proposed. The determination is based on an energy transfer from Pefloxacin to terbium (III). The metal ion enhances the weak CL signal produced by the KMnO4/H2SO3/Pefloxacin system. A modified simplex method was used to optimize chemical and instrumental variables. The influence of the interaction of the permanganate, Tb (III), sodium sulphite and sulphuric acid concentrations, flow rate and injected sample volume was thoroughly investigated by using a modified simplex optimization procedure...
December 5, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Kallie Jiang, Daniel R Hill, Matthew J Elrod
Laboratory and field measurements have demonstrated that 2-methyl glyceric acid (2-MG) is the base component of a wide range of chemical species found in methacrolein-derived secondary organic aerosol (SOA). In order to explore the recently proposed hypothesis that a lactone oxidation intermediate is the origin of 2-MG and its derivatives in SOA, nuclear magnetic resonance techniques were used to study kinetics and reaction products of the aqueous phase reactions of a model lactone, -propiolactone (BPL)...
December 8, 2017: Journal of Physical Chemistry. A
Dan Yan, Hui-Ji Li, Hou-Qin Cai, Mei Wang, Chun-Chang Wang, Hai-Bo Yi, Xiao-Bo Min
The mechanism of As(V) removal from the drinking water and industrial effluents by iron materials remains unclear at the molecular level. In this work, the association of Fe-based materials with As(V) species was explored using density functional theory and ab initio calculations. Solvent separated ion pair structures of [FeH2AsO4]2+aq species may be dominant in an acidic solution of FeAs complex. The association trend of H2AsO4- species by Fe3+aq is found to be quite weak in the aqueous solution, which may be attributed to the strong hydration of Fe3+aq and [FeH2AsO4]2+ species...
November 30, 2017: Chemosphere
S Redlberger, S Fischer, H Köhler, R Diller, P Reinhold
There is a paucity of published data reporting acid-base equilibrium in goats, and no information is available on how the acid-base complexity changes when suckling goat kids become ruminants. The aims of this study were to evaluate young healthy goats for age-related changes in serum proteins, metabolites, and electrolytes; differences in results when the Henderson-Hasselbalch equation or strong ion approaches were used were also assessed. To assess biological variability and reproducibility, two consecutive long-term studies, each lasting from the 6th to 56th week of life (wl), were performed in 15 (Study 1) and 10 (Study 2) animals...
November 2017: Veterinary Journal
Qi Zhou, Tiantian Luo, Heng Yang, Cheng Liang, Luru Jing, Wenjun Luo
Acid extracting aluminum from fly ash would produce pestilent secondary fly ash slurry with strong acidity, high content of Cl- and residual Al3+ that is difficult to be further used. In order to achieve the zero emission, a potential integrated treatment process for reutilization was proposed in this paper. By intelligent use of residual Al3+ in sludge as catalyst, hydrophobic modification of solid particle was taken with fatty acid via a heterogeneous esterification at normal temperature. Due to the solvophobic force, moisture content of its filter cake was 36...
November 6, 2017: Journal of Colloid and Interface Science
Xiangzhao Ai, Linna Lyu, Jing Mu, Ming Hu, Zhimin Wang, Bengang Xing
Lanthanide-doped upconversion nanocrystals (UCNs) have attracted much attention in recent years based on their promising and controllable optical properties, which allow for the absorption of near-infrared (NIR) light and can subsequently convert it into multiplexed emissions that span over a broad range of regions from the UV to the visible to the NIR. This article presents detailed experimental procedures for high-temperature co-precipitation synthesis of core-shell UCNs that incorporate different lanthanide ions into nanocrystals for efficiently converting deep-tissue penetrable NIR excitation (808 nm) into a strong blue emission at 480 nm...
November 10, 2017: Journal of Visualized Experiments: JoVE
Olgary Figueroa-Santiago, Ana M Espino
Fasciola hepatica is a parasitic helminth that induces Th2/Treg responses in its mammalian host. Some reports have suggested that ESPs achieve these polarized immune responses by delaying the activation of dendritic cells and macrophages during the early stages of innate immunity, a process that is mediated by TLR4. The present study aimed to investigate whether TLRs other than TLR4 could also be targeted by F. hepatica ESPs. To achieve this aim a screening system was optimized using THP1-Blue CD14 cells. ESPs were first separated based on their molecular weight and according their net charge by ion exchange chromatography (IEC)...
2017: Annals of Clinical Pathology
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"