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#33108185   2020/10/27 To Up

Exploring Cation-Anion Redox Processes in One-Dimensional Linear Chain Vanadium Tetrasulfide Rechargeable Magnesium Ion Cathodes.

For magnesium ion batteries (MIBs) to be used commercially, new cathodes must be developed that show stable reversible Mg intercalation. VS is one such promising material, with vanadium and disulfide anions [S] forming one-dimensional linear chains, with a large interchain spacing (5.83 Å) enabling reversible Mg insertion. However, little is known about the details of the redox processes and structural transformations that occur upon Mg intercalation and deintercalation. Here, employing a suite of local structure characterization methods including X-ray photoelectron spectroscopy (XPS), V and S X-ray absorption near-edge spectroscopy (XANES), and V Hahn echo and magic-angle turning with phase-adjusted sideband separation (MATPASS) NMR, we show that the reaction proceeds via internal electron transfer from V to [S], resulting in the simultaneous and coupled oxidation of V to V and reduction of [S] to S. We report the formation of a previously unknown intermediate in the Mg-V-S compositional space, MgVS, comprising [VS] tetrahedral units, identified by using density functional theory coupled with an evolutionary structure-predicting algorithm. The structure is verified experimentally via X-ray pair distribution function analysis. The voltage associated with the competing conversion reaction to form MgS plus V metal directly is similar to that of intermediate formation, resulting in two competing reaction pathways. Partial reversibility is seen to re-form the V and S containing intermediate on charging instead of VS. This work showcases the possibility of developing a family of transition metal polychalcogenides functioning via coupled cationic-anionic redox processes as a potential way of achieving higher capacities for MIBs.
Sunita Dey, Jeongjae Lee, Sylvia Britto, Joshua M Stratford, Evan N Keyzer, Matthew T Dunstan, Giannantonio Cibin, Simon J Cassidy, Mahmoud Elgaml, Clare P Grey

2253 related Products with: Exploring Cation-Anion Redox Processes in One-Dimensional Linear Chain Vanadium Tetrasulfide Rechargeable Magnesium Ion Cathodes.

100 ml.2 500 gm.25 ml.1mg1 mg10 5mg100 μg

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#33108069   2020/10/27 To Up

CIM6P/IGF-2 Receptor Ligands Reverse Deficits in Angelman Syndrome Model Mice.

Angelman syndrome (AS), a genetic disorder that primarily affects the nervous system, is characterized by delayed development, intellectual disability, severe speech impairment, and problems with movement and balance (ataxia). Most affected children also have recurrent seizures (epilepsy). No existing therapies are capable of comprehensively treating the deficits in AS; hence, there is an urgent need to identify new treatments. Here we show that insulin-like growth factor 2 (IGF-2) and mannose-6-phosphate (M6P), ligands of two independent binding sites of the cation-independent M6P/IGF-2 receptor (CIM6P/IGF-2R), reverse most major deficits of AS modeled in mice. Subcutaneous injection of IGF-2 or M6P in mice modeling AS restored cognitive impairments as assessed by measurements of contextual and recognition memories, motor deficits assessed by rotarod and hindlimb clasping, and working memory/flexibility measured by Y-maze. IGF-2 also corrected deficits in marble burying and significantly attenuated acoustically induced seizures. An observational battery of tests confirmed that neither ligand changed basic functions including physical characteristics, general behavioral responses, and sensory reflexes, indicating that they are relatively safe. Our data provide strong preclinical evidence that targeting CIM6P/IGF-2R is a promising approach for developing novel therapeutics for AS. LAY SUMMARY: There is no effective treatment for the neurodevelopmental disorder Angelman syndrome (AS). Using a validated AS mouse model, the Ube3a , in this study we show that systemic administration of ligands of the cation independent mannose-6-phosphate receptor, also known as insulin-like growth factor 2 receptor (CIM6P/IGF-2R) reverses cognitive impairment, motor deficits, as well as seizures associated with AS. Thus, ligands that activate the CIM6P/IGF-2R may represent novel, potential therapeutic targets for AS.
Emmanuel Cruz, Giannina Descalzi, Adam Steinmetz, Helen E Scharfman, Aaron Katzman, Cristina M Alberini

2854 related Products with: CIM6P/IGF-2 Receptor Ligands Reverse Deficits in Angelman Syndrome Model Mice.

200ul200ul100ug Lyophilized100ug2000 Units20ug 5 G

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#33108043   2020/10/27 To Up

Reduction of π-Expanded Cyclooctatetraene with Lithium: Stabilization of the Tetraanion through Internal Li+ Coordination.

The chemical reduction of a π-expanded polycyclic framework comprising a cyclooctatetraene moiety, octaphenyltetrabenzocyclooctatetraene, with lithium metal readily affords the corresponding tetraanion instead of the expected aromatic dianion. As revealed by X-ray crystallography, the highly contorted tetraanion is stabilized by coordination of two internally bound Li + cations, while two external cations remain solvent-separated. The variable-temperature 7 Li NMR spectra in THF confirm the presence of three types of Li + ions and clearly differentiate internal binding, consistently with the crystal structure. Density functional theory calculations suggest that the formation of the highly charged tetrareduced carbanion is stabilized through Li + coordination under the applied experimental conditions.
Zheng Zhou, Yikun Zhu, Zheng Wei, John Bergner, Christian Neiß, Susanne Doloczki, Andreas Görling, Milan Kivala, Marina A Petrukhina

1007 related Products with: Reduction of π-Expanded Cyclooctatetraene with Lithium: Stabilization of the Tetraanion through Internal Li+ Coordination.

5 G100 μg100 μg100 μg100 μg100 μg100 μg100 μg100 μg100 μg100 μg

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#33107867   2020/10/27 To Up

Complexation-association-extraction spectrophotometric determination of Pt cations based on a multi-reagent analytical system with I anions and 2-[2-[4-[(2-cyanoethyl)methylamino]phenyl]vinyl]-1,3,3-trimethyl-3-indolium cations.

A new multi-reagent analytical system with 2-[2-[4-[(2-cyanoethyl)methylamino]phenyl]vinyl]-1,3,3-trimethyl-3H-indolium chloride (CPVTI), which is a styryl hemicyanine cationic dye with good photostability and a high molar absorption coefficient, as its core is first established and utilized successfully to determine the content of Pt ions via a spectrophotometric method. The process involves two treatment steps: adding CPVTI and I solutions to the Pt solution to be detected, and then using butyl acetate for vortex liquid-liquid extraction. A Pt cation can be incorporated into the CPVTI cation with the help of an I- anion, initially converting the Pt cation into a [PtI6]2- complex anion. After forming a [PtI62-·2CPVTI+](aq) ion associate in the aqueous phase, the Pt cation can be extracted selectively by butyl acetate with maximum extraction efficiency, and exists as [PtI62-·2CPVTI+](org) in the extract phase. Via the formation of the iodo-complex of Pt and its ion associate with CPVTI, and the extraction with butyl acetate, Pt is selectively partitioned into the butyl acetate extractant in a step-by-step manner with good interference resistance. In the CPVTI-Pt-I analytical system, the charge state of CPVTI is retained by adjustment with H2SO4; the monovalent CPVTI+ presents a strong spectrophotometric absorbance signal at 530 nm with long-term stability, which allows determination of the Pt content. The system shows a high molar absorption coefficient of 6.52 × 104 L mol-1 cm-1 at 530 nm, a lower limit of detection of 0.07 mg L-1, and a good Sandell's sensitivity of 0.0030 μg cm-2. Mechanistic analysis of the establishment of the system, concentration optimization, standard working curve, system sensitivity and stability, resistance against interference from diverse metal ions, and practical applications are investigated and discussed.
Si Chen, Youkuo Chen, Yongchun Xu, Wei Chen, Shubin Chen, Lili Hu, Georges Boulon

2285 related Products with: Complexation-association-extraction spectrophotometric determination of Pt cations based on a multi-reagent analytical system with I anions and 2-[2-[4-[(2-cyanoethyl)methylamino]phenyl]vinyl]-1,3,3-trimethyl-3-indolium cations.

1 kit(s) 1 Set10 mg100 μg100ug Lyophilized1 Set100 extractions1 Set10 mg

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#33107864   // To Up

Low energy consumption electrically regenerated ion-exchange for water desalination.

A new regeneration method of ion exchange resin named Adjacent Bed Electrically Regenerated Ion-exchange (ABERI) was proposed to eliminate the environmental impact of traditional chemical regeneration and improve the economy of replacing chemical regeneration with electrical regeneration. The desalting operation of ABERI was the same as the conventional mixed bed. When the resins were exhausted, anion and cation resins were separated and then packed in a dedicated regenerator adjacently. The resins were regenerated by the H and OH ions produced from a pair of electrodes installed on both sides of the resin bed. By optimizing the regeneration time, current, and feed water flow rate, the energy consumption of ABERI was 0.38 kWh/m water; that is, 54% of that of another electrical regeneration technology, membrane-free electrodeionization (MFEDI). Compared with MFEDI, the quality and quantity of purified water produced after regeneration were improved. In ABERI, the average conductivity and the volume (times of bed volumes) of the purified water are 0.9 μS/cm and 109; that is, 75 and 133% of that of MFEDI, respectively. The preliminary economic analysis showed that ABERI offers the potential to regenerate ion exchange resin in an eco-friendly and cost-effective manner.
San He, Xiaozhuo Zhang, Xingyu Xia, Chuanjun Wang, Sulin Xiang

1392 related Products with: Low energy consumption electrically regenerated ion-exchange for water desalination.

20 L 250 mg0.1ml (1mg/ml)0,1 ML 1 G1 LITRE250ML96 Well 100ul

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#33107850   // To Up

Impact of monovalent cations on the separation performance of graphene oxide membrane for different organic matters.

Graphene oxide (GO) membrane has become a promising membrane due to its advantages of high flux, good anti-pollution performance, and controllable cost. Since wastewater contains inorganic ions and organic substances, the effect of inorganic ions on the removal of organic matters has attracted attention. This study investigated the impact of monovalent cations (Na and K) on the removal of different organic matters by GO membranes. The results showed that the removal by GO membranes of both macromolecular organic compounds (humic acid, sodium alginate, and bull serum albumin) and small molecular organic substances (new coccine, methyl orange, and methylene blue) were high (>75%). The coexisting Na caused the increase in flux and the decrease in removal of small molecular organic matters, while the impact on the removal of macromolecular organic matters was weak. The impact of the coexisting K was weaker than Na. With the crosslinking of ethylenediamine, the structure of GO membrane was more stable. The impacts of Na on the flux and separation performance of crosslinked membranes were less than that of non-crosslinked membranes. This suggests that crosslinked GO membrane has more potential for practical wastewater treatment.
Huabiao Qi, Xin Zhao, Han Li, Yuang Che, Can Wang

1467 related Products with: Impact of monovalent cations on the separation performance of graphene oxide membrane for different organic matters.

20 ug 5 G10 plates 100 G100ul250 mg 6 ml Ready-to-use 100ug Lyophilized0.1 ml10 membrane minimum

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#33107734   2020/10/27 To Up

Table-Top X-ray Spectroscopy of Benzene Radical Cation.

Ultrafast table-top X-ray spectroscopy at the carbon K-edge is used to measure the X-ray spectral features of benzene radical cations (Bz). The ground state of the cation is prepared selectively by two-photon ionization of neutral benzene, and the X-ray spectra are probed at early times after the ionization by transient absorption using X-rays produced by high harmonic generation (HHG). Bz is well-known to undergo Jahn-Teller distortion, leading to a lower symmetry and splitting of the π orbitals. Comparison of the X-ray absorption spectra of the neutral and the cation reveals a splitting of the two degenerate π* orbitals as well as an appearance of a new peak due to excitation to the partially occupied π-subshell. The π* orbital splitting of the cation, elucidated on the basis of high-level calculations in a companion theoretical paper [Vidal et al. http://dx.doi.org/10.1021/acs.jpca.0c08732], is discovered to be due to both the symmetry distortion and even more dominant spin coupling of the unpaired electron in the partially vacant π orbital (from ionization) with the unpaired electrons resulting from the transition from the 1s core orbital to the fully vacant π* orbitals.
Michael Epshtein, Valeriu Scutelnic, Zheyue Yang, Tian Xue, Marta L Vidal, Anna I Krylov, Sonia Coriani, Stephen R Leone

2082 related Products with: Table-Top X-ray Spectroscopy of Benzene Radical Cation.

25 mg8 Array supply5 mg10 mg10 mg25 g1 ml1 mg 25 G1 module100 mg

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#33107560   2020/06/02 To Up

Determination of Free and Total Choline and Free and Total Carnitine in Infant Formula and Adult/Pediatric Nutritional Formula by Liquid Chromatography/Tandem Mass Spectrometry (HPLC-MS/MS): A Multi-laboratory Testing Study, Final Action 2015.10.

A multi-laboratory study was conducted on AOAC First Action Method 2015.10 "Determination of Free and Total Choline and Free and Total Carnitine in Infant Formula and Adult/Pediatric Nutritional Formula by Liquid Chromatography/Tandem Mass Spectrometry (HPLC-MS/MS)."
Jeffrey Shippar, David Ellingson, Jane Sabbatini

1239 related Products with: Determination of Free and Total Choline and Free and Total Carnitine in Infant Formula and Adult/Pediatric Nutritional Formula by Liquid Chromatography/Tandem Mass Spectrometry (HPLC-MS/MS): A Multi-laboratory Testing Study, Final Action 2015.10.

50 ug 200ul10 mg100 mg100ul5mg25 mg100 mg 25 MG200ug10 mg

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#33107516   2020/10/27 To Up

Masking specific effects of ionic liquid constituents at the solid-liquid interface by surface functionalization.

Ion specific effects of ionic liquid (IL) constituents on the surface charge and aggregation properties of two types of particles (positively charged amidine (AL) and polyimidazolium-functionalized sulfate (SL-IP-2) latexes) were investigated in IL solutions containing different anions and the 1-butyl-3-methylimidazolium cation. For the AL systems, the affinity of IL anions to the particle surface followed the sequence chloride < bromide < nitrate < acetate. The critical coagulation concentration values decreased in the same order indicating that ion specific adsorption determines the surface charge density and the extent of the repulsive interparticle forces. In contrast, no tendencies were observed for the SL-IP-2 particles, i.e., both charge and aggregation features were insensitive to the type of anions. This surprising behavior sheds light on that surface functionalization with the polyimidazolium compound effectively masks interfacial ion specific effects. These results indicate new possible routes to the design of processable particle dispersions in ILs irrespective of their composition.
Bojana Katana, Dóra Takács, Felix D Bobbink, Paul J Dyson, Nizar B Alsharif, Matija Tomšič, Istvan Szilagyi

2890 related Products with: Masking specific effects of ionic liquid constituents at the solid-liquid interface by surface functionalization.

50 ug100 200 assays1000 assays20 50 ug50 ug20 50 ug150/kit1000 assays50 ug

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