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In: International Journal of Energy Research, 25 June 2014, Vol.38(8), pp.1016-1023

Description: In this paper, activated aluminum powder was prepared by magnetic grinding with a homemade equipment and hydrolyzed in alkaline solution to produce hydrogen. The results showed that the prepared aluminum powder could improve hydrolysis reactivity effectively and have high hydrogen yield in alkaline solution (up to 1340 mL/g). It was found that grinding time, reaction temperature and grinding media could significantly affect the hydrolysis reaction while alloy components had little effect. Aluminum powder ground for 40 min can produce hydrogen 1340 mL/g within 6 min under optimal reaction temperature of 323 K. Copyright © 2013 John Wiley & Sons, Ltd. In this paper, activated aluminum powder was prepared by magnetic grinding with homemade equipment and hydrolyzed in alkaline solution to produce hydrogen. The result shows that the prepared aluminum powder could improve hydrolysis reactivity effectively and have high hydrogen yield in alkaline solution. Aluminum powder ground for 40 min can produce hydrogen 1340 mL/g within 6 min under the reaction temperature of 323 K. The method needs lower production cost, could solve the hydrogen storage and environmental pollution problem and efficiently produce large‐scale hydrogen. In summary, this method could offer a fast, economic, convenient and green way for hydrogen production.

Keywords: Aluminum Powder ; Hydrogen Generation ; Hydrolysis Reaction ; Magnetic Grinding ; Sodium Hydroxide

ISSN: 0363-907X

E-ISSN: 1099-114X

DOI: 10.1002/er.3123

Language: English

In: Chemistry – A European Journal, 03 February 2014, Vol.20(6), pp.1731-1736

Description: An efficient method for the phosphine‐catalyzed [3+2] cycloaddition reaction of azomethine imines with diphenylsulfonyl alkenes to give dinitrogen‐fused bi‐ or tricyclic heterocyclic compounds in high yields has been described. Moreover, two phenylsulfonyl groups installed on the heterocyclic products could be conveniently removed or transformed to other functional groups, making the reaction more useful. : Phosphine‐catalyzed [3+2] cycloaddition of azomethine imines and phenylsulfonyl alkenes was accomplished. The reactions are operationally simple and proceed smoothly under mild reaction conditions, affording various 1,2‐dinitrogen‐containing heterocycles in moderate to excellent yields (see scheme).

Keywords: Alkenes ; Azomethine Imine ; Catalysis ; Cycloaddition Reactions ; Phosphine

ISSN: 0947-6539

E-ISSN: 1521-3765

DOI: 10.1002/chem.201303625

Language: English

In: ChemSusChem, 11 September 2017, Vol.10(17), pp.3352-3357

Description: A new sulfonic/carboxylic dual‐acid catalyst based on sulfur‐rich graphene oxide (GO‐S) was readily prepared and used as a highly efficient and reusable solid acid catalyst toward the esterification of oleic acid with methanol for biodiesel production. Higher yields of methyl oleate (98 %) and over 3 times higher turnover frequencies (TOFs) were observed for the GO‐S dual‐acid catalyst, compared to liquid sulfuric acid or other carbon‐based solid acid catalysts. The “acidity” of sulfonic acid groups was enhanced by the addition of carboxylic acid groups as the combination of the two acids enhances their inherent activity by associative interaction. : The presence of −COOH groups significantly promote the biodiesel yield and turnover frequency owing to the synergistic effect between −SOH and −COOH groups.

Keywords: Dual-Acid Catalyst ; Esterification ; Graphene Oxide ; Heterogeneous Catalysis ; Solid Acid

ISSN: 1864-5631

E-ISSN: 1864-564X

DOI: 10.1002/cssc.201700950

In: Journal of Magnetic Resonance Imaging, March 2014, Vol.39(3), pp.584-589

Description: Byline: Mukta D. Agrawal, Kevin W. Mennitt, Honglei Zhang, Benjamin Samstein, Tomoaki Kato, Jean C. Emond, Silvina P. Dutruel, Nanda Deepa Thimmappa, Martin R. Prince Keywords: MR cholangiography; gadoxetate; living related liver donor; hepatic MRI Purpose To assess low-dose morphine for distension and improved visualization of intrahepatic bile ducts on T1 MR cholangiography (MRC) in preoperative imaging of potential liver donors. Materials and Methods Sixty-nine consecutive potential living related liver donors (mean age, 39 years; age range, 20 to 59 years) referred for pre-transplant MRI evaluation were evaluated without (n=30) or with (n=39) intravenous morphine injection (0.04 mg/kg). Morphine was injected pre-MRI while establishing intravenous access to allow a1/41 h for biliary distension before T1 MRC. Three radiologists reviewed intrahepatic biliary branch order visualization, common bile duct (CBD) diameter, and overall image quality. In 25 patients undergoing liver donation surgery, T1 MRC findings were correlated with intraoperative findings. This retrospective study was approved by the institutional review board. Results Biliary visualization was improved post-morphine administration with biliary duct branch order visualization score of 3.2 and 3.3 at 45 and 60 min, respectively, compared with 2.7 without morphine (P 0.002); CBD diameter measured 5.3 and 5.5 versus 4.1 mm (P 0.005), and overall image quality score was 2.4 and 2.6 versus 1.8 (P 0.0006). Operative notes confirmed T1 MRC findings in 6/11 donors without morphine and 14/14 donors with morphine. Conclusion Intravenous low-dose morphine distends and improves visualization of bile ducts on T1 gadoxetate MRC. J. Magn. Reson. Imaging 2014;39:584-589. [c] 2013 Wiley Periodicals, Inc. Supporting information: Additional Supporting Information may be found in the online version of this article Additional Supporting Information may be found in the online version of this article. CAPTION(S): Supp. Fig. S6. Axial cine loop of 3D spiral LAVA with sliding window reconstruction at 3-s temporal update rate used for dynamic liver MR imaging in living related liver donors.

Keywords: Mr Cholangiography ; Gadoxetate ; Living Related Liver Donor ; Hepatic Mri

ISSN: 1053-1807

E-ISSN: 1522-2586

DOI: 10.1002/jmri.24188

Language: English

In: Journal of Polymer Science Part B: Polymer Physics, 01 March 2010, Vol.48(5), pp.509-513

Description: polysaccharide (LBP) was subjected to ultrasonic degradation under the controlled conditions, such as, temperature, irradiation time, initial pH value, and concentration of solution. The ultrasonic degradation of LBP was demonstrated by the changes of intrinsic viscosity. Viscometry was used to study the degradation behavior and a kinetic model was developed to estimate the degradation rate. The results showed that the degradation rate was reduced with the increase of solution concentration and pH, and increased with increase of temperature. The relationship between the number average molar mass () and intrinsic viscosities as interpreted using the Mark‐Houwink equation suggested that LBP adopted a flexible coil conformation in aqueous solution. The activation energy of ultrasonic degradation of LBP is 26.5 kJ/mol, which indicates that the ultrasonic degradation is a convenient, time saving, and cost‐efficient method for obtaining a desired molecular weight. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 509–513, 2010

Keywords: Degradation ; Kinetics Polym. ; Lycium Barbarum ; Polysaccharides ; Viscosity

ISSN: 0887-6266

E-ISSN: 1099-0488

DOI: 10.1002/polb.21914

Language: English

In: Macromolecular Symposia, April 2007, Vol.251(1), pp.25-32

Description: Myoglobin was used as a model protein to study the effect of polyelectrolyte on protein thermal stability for solutions. Stereoregular polystyrene sulfonate was used to investigate the effect of chain properties on protein polyion binding affinity. Turbidity measurement indicate stronger binding to protein of atactic polystyrene sulfonate than isotactic polystyrene sulfonate, an effect that might be due to the higher chain flexibility of the atactic form. Differential scanning calorimetry (DSC) and small angle x‐ray (SAXS) scattering indicate the presence of the polyelectrolyte has a destabilizing effect on the protein. The results showed that, although the presence of polyelectrolytes has no effect on myoglobin structure at room temperature at pH 7.4, myoglobin stability is reduced as the temperature is elevated. This effect is linked to the binding of the protein to the polylectrolyte. This binding is probably driven by a combination of electrostatic and hydrophobic interactions, the latter of which are enhanced at higher temperatures.

Keywords: Differential Scanning Calorimetry ; Polyelectrolyte ; Protein ; Small Angle X‐Ray Scattering ; Thermodenaturation

ISSN: 1022-1360

E-ISSN: 1521-3900

DOI: 10.1002/masy.200750504

Language: English

In: Journal of Magnetic Resonance Imaging, September 2007, Vol.26(3), pp.817-817

Keywords: Medicine;

ISSN: 1053-1807

E-ISSN: 1522-2586

DOI: 10.1002/jmri.21019

In: International Journal of Energy Research, July 2019, Vol.43(9), pp.4797-4806

Description: Currently, recycling waste aluminum materials are of significant importance for reducing environmental pollution and improving economic efficiency. In this paper, aluminum (Al) powder prepared from waste Al cans with magnetic grinding method was directly used in hydrolysis for hydrogen generation. The prepared waste Al cans powder was characterized by scanning electron microscope (SEM), X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), atomic absorption spectrophotometer (AAS), and density analysis. The results showed that grinding time, NaOH concentration, and reaction temperature affected the hydrolysis rate and hydrogen yield markedly; 1 g of Al cans powder with grinding time of 40 minutes could produce 1296‐mL hydrogen within 6 minutes under the optimal reaction conditions. The reaction kinetics study demonstrated that the hydrolysis of Al cans powder is kinetically controlled while hydrolysis of Al cans flakes is diffusively controlled. The hydrolysis mechanism was also predicted based on the experimental results and kinetic study. The generation of hydrogen from hydrolysis of waste Al cans powder with low‐concentrated alkaline solution is a promising way to diminish environmental pollution and instrument corrosion. Waste Al cans was treated by magnetic grinding and used in hydrolysis for highly efficient hydrogen production to avoid solid waste pollution and improve economic efficiency.

Keywords: Aluminum Cans ; Alkaline Solution ; Hydrogen ; Hydrolysis ; Kinetics

ISSN: 0363-907X

E-ISSN: 1099-114X

DOI: 10.1002/er.4621

In: International Journal of Energy Research, 25 June 2019, Vol.43(8), pp.3823-3836

Description: Steam reforming of ethanol (SRE) over non‐noble metal catalysts is normally conducted at high temperature (〉600°C) to thermodynamically favour the catalytic process and carbon deposition mitigation. However, high temperature inhibits water‐gas shift reaction (WGSR) and therefore restrains the yield of H and leads to the formation of an excessive amount of CO. The modification of non‐noble metal catalyst to enhance WGSR is an attractive alternative. In this study, CeO was firstly loaded onto a nano‐scaled NiMgO matrix and subsequently used as the catalyst for hydrogen production via SRE. Morphology of the catalyst materials was characterized by using a series of technologies, while H‐temperature programmed reduction (H‐TPR), CO‐temperature programmed deposition (CO‐TPD), and X‐ray photoelectron spectroscopy (XPS), were employed to study the surface nickel, ceria clusters, and their interactions. The catalytic activity and durability of the catalyst were studied in the temperature region of 500°C to 800°C. The CeO‐coated nano NiMgO matrix exhibited an outstanding hydrogen yield of 4.82 mol/mol under a high gas hourly space velocity (GHSV) of 200 000 hour. It is found that the unique Ni‐CeO structure facilitates the adsorption of CO on the surface and therefore promotes the effective hydrogen production via WGSR. Moreover, this modified NiMgO matrix was found to be a more robust and anticoking nanocatalyst because of reversible switch between Ce and Ce. The NixMgyO solid solution in nanoscale was studied in ESR at broad temperatures. The surface CeOx promoted the H2 yield mainly because of the enhancement of water‐gas shift reaction. CO‐TPD test confirmed the enhancement of CO adsorption over surface nickel by addition of Ce. Oxygen vacancy on CeO2 played an essential role in anticarbon deposition. The NixMgyO‐Ce showed a high H2 yield (4.82 mol/molethanol) at a GHSV of 200 000 hour−1.

Keywords: Ceo 2 ; Hydrogen Production ; Ni X Mg Y O Matrix ; Steam Reforming Of Ethanol ; Water‐Gas Shift Reaction

ISSN: 0363-907X

E-ISSN: 1099-114X

DOI: 10.1002/er.4549

In: Energy Technology, May 2019, Vol.7(5), pp.n/a-n/a

Description: A Co‐MOF coating is prepared on a Ti‐modified hematite nanosheet photoelectrode via a simple in situ hydrothermal method. The Co‐MOF@TiFe photoanode has enhanced photocurrent and negatively shifts the onset potential of photocurrent. The in situ hydrothermal method increases the surface roughness of the photoanode. The Co‐MOF acts as a catalyst, surface passivation layer, and heterojunction.

Keywords: Anodic Electrodeposition ; Co-Based Metal–Organic Frameworks ; Nanosheet Hematite ; Photoelectrochemical Performance

ISSN: 2194-4288

E-ISSN: 2194-4296

DOI: 10.1002/ente.201801069