In Situ Magnetic Alignment of a Slurry of Tandem Semiconductor Microwires Using a Ni Catalyst

The magnetic alignment of cellulose nanocrystals (CNC) and lepidocrocite nanorods (LpN), pristine and in hybrid suspensions has been investigated using contrast-matched small-angle neutron scattering (SANS) under in situ magnetic fields (0 – 6.8 T) and polarized optical microscopy. The pristine CNC (diamagnetic) and pristine LpN (paramagnetic) align perpendicular and parallel to the direction of field, respectively. The alignment of both the nanoparticles in their hybrid suspensions depends on the relative amount of the two components (CNC and LpN) and strength of the applied magnetic field. In the presence of 10 wt% LpN and fields < 1.0 T, the CNC align parallel to the field. In the hybrid containing lower amount of LpN (1 wt%), the ordering of CNC is partially frustrated in all range of magnetic field. At the same time, the LpN shows both perpendicular and parallel orientation, in the presence of CNC. This study highlights that the natural perpendicular ordering of CNC can be switched to parallel by weak magnetic fields and the incorporation of paramagnetic nanoparticle as LpN, as well it gives a method to influence the orientation of LpN.

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C–N Ring Construction: The Waser Synthesis of Jerantinine E

Organic Synthesis ◽

10.1093/oso/9780190646165.003.0053 ◽

2017 ◽

Author(s):

Douglass F. Taber

Keyword(s):

Ni Catalyst ◽

University Of Alberta ◽

Princeton University ◽

In Situ Preparation ◽

National University ◽

The University ◽

École Polytechnique ◽

Pais Vasco ◽

Multicomponent Coupling

James A. Bull of Imperial College London prepared (J. Org. Chem. 2013, 78, 6632) the aziridine 2 with high diastereocontrol by adding the anion of diiodomethane to the imine 1. Karl Anker Jørgensen of Aarhus University observed (Chem. Commun. 2013, 49, 6382) high ee in the distal aziridination of 3 to give 4. Benito Alcaide of the Universidad Complutense de Madrid and Pedro Almendros of ICOQ- CSIC Madrid reduced (Adv. Synth. Catal. 2013, 355, 2089) the β-lactam 5 to the azetidine 6. Hiroaki Sasai of Osaka University added (Org. Lett. 2013, 15, 4142) the allenoate 8 to the imine 7, delivering the azetidine 9 in high ee. Tamio Hayashi of Kyoto University, the National University of Singapore, and A*STAR devised (J. Am. Chem. Soc. 2013, 135, 10990) a Pd catalyst for the enantioselective addition of the areneboronic acid 11 to the pyrroline 10 to give 12. Ryan A. Brawn of Pfizer (Org. Lett. 2013, 15, 3424) reported related results. Nicolai Cramer of the Ecole Polytechnique Fédérale de Lausanne developed (J. Am. Chem. Soc. 2013, 135, 11772) a Ni catalyst for the cyclization of the formamide 13 to the lactam 14. Andrew D. Smith of the University of St. Andrews used (Org. Lett. 2013, 15, 3472) an organocatalyst to cyclize 15 to 16. Jose L. Vicario of the Universidad del Pais Vasco effected (Synthesis 2013, 45, 2669) the multicomponent coupling of 17, 18, and 19, mediated by an organocatalyst, to construct 20 in high ee. André Beauchemin of the University of Ottawa explored (J. Org. Chem. 2013, 78, 12735) the thermal cyclization of ω-alkenyl hydroxyl amines such as 21. Abigail G. Doyle of Princeton University developed (Angew. Chem. Int. Ed. 2013, 52, 9153) a Ni catalyst for the enantioselective addition of aryl zinc bromides such as 24 to the prochiral 23, to give 25 in high ee. Dennis G. Hall of the University of Alberta developed (Angew. Chem. Int. Ed. 2013, 52, 8069) an in situ preparation of the allyl boronate 26 in high ee. Addition to the aldehyde 27 proceeded with high diasteroselectivity.

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In situ nanocrystalline HZSM-5 zeolites encaged heteropoly acid H3PMo12O40 and Ni catalyst for hydroconversion of n-octane

Chemical Engineering Science ◽

10.1016/j.ces.2007.05.013 ◽

2007 ◽

Vol 62 (16) ◽

pp. 4469-4478 ◽

Cited By ~ 20

Author(s):

Lidong Chen ◽

Xiangsheng Wang ◽

Xinwen Guo ◽

Hongchen Guo ◽

Hai’ou Liu ◽

...

Keyword(s):

Heteropoly Acid ◽

Ni Catalyst

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Water as Hydrogen Source for Highly Efficient Conversion of Biomass-Derived Levulinic Acid into γ-Valerolactone over Raney Ni Catalyst

10.26434/chemrxiv.14365583.v1 ◽

2021 ◽

Author(s):

Zhuang Ma ◽

Binbin Jin ◽

Yalin Guo ◽

Xuejun Li ◽

Guodong Yao ◽

...

Keyword(s):

Levulinic Acid ◽

Noble Metals ◽

Large Scale ◽

Precious Metals ◽

Ni Catalyst ◽

Hydrothermal Conditions ◽

Highly Efficient ◽

Operation Process ◽

Raney Ni

Gamma (γ)-valerolactone (GVL) is a promising liquid for energy and carbon-based chemicals. Although many researches regarding the GVL synthesis from carbohydrate biomass, most of them involve the use of noble metals accompanying with the high-purity and high-pressure gaseous hydrogen, existing high cost in large-scale application and safety risk during the transportation and operation process. In this paper, the cheap metal Fe was employed as a reductant for splitting water to produce hydrogen under mild hydrothermal conditions, and commercial Raney Ni was used as a catalyst for in situ hydrogenation of biomass-derived levulinic acid (LA). More than 95% yield of GVL can be attained at 150 oC for 2 h and ~ 90% yield of GVL was also achieved at 100 oC by increasing the reaction time to 5 h. Furthermore, Raney Ni remains the stable catalytic activity after being recycled for 4 times at 150 oC. This work provides a safe and facile process for highly efficient hydrogenation of biomass-derived LA to GVL without precious metals.

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Water as Hydrogen Source for Highly Efficient Conversion of Biomass-Derived Levulinic Acid into γ-Valerolactone over Raney Ni Catalyst

10.26434/chemrxiv.14365583 ◽

2021 ◽

Author(s):

Zhuang Ma ◽

Binbin Jin ◽

Yalin Guo ◽

Xuejun Li ◽

Guodong Yao ◽

...

Keyword(s):

Levulinic Acid ◽

Noble Metals ◽

Large Scale ◽

Precious Metals ◽

Ni Catalyst ◽

Hydrothermal Conditions ◽

Highly Efficient ◽

Operation Process ◽

Raney Ni

Gamma (γ)-valerolactone (GVL) is a promising liquid for energy and carbon-based chemicals. Although many researches regarding the GVL synthesis from carbohydrate biomass, most of them involve the use of noble metals accompanying with the high-purity and high-pressure gaseous hydrogen, existing high cost in large-scale application and safety risk during the transportation and operation process. In this paper, the cheap metal Fe was employed as a reductant for splitting water to produce hydrogen under mild hydrothermal conditions, and commercial Raney Ni was used as a catalyst for in situ hydrogenation of biomass-derived levulinic acid (LA). More than 95% yield of GVL can be attained at 150 oC for 2 h and ~ 90% yield of GVL was also achieved at 100 oC by increasing the reaction time to 5 h. Furthermore, Raney Ni remains the stable catalytic activity after being recycled for 4 times at 150 oC. This work provides a safe and facile process for highly efficient hydrogenation of biomass-derived LA to GVL without precious metals.

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In situ exsolution of Ni particles on the PrBaMn2O5 SOFC electrode material monitored by high temperature neutron powder diffraction under hydrogen

Journal of Materials Chemistry A ◽

10.1039/c9ta10159d ◽

2020 ◽

Vol 8 (7) ◽

pp. 3590-3597 ◽

Cited By ~ 5

Author(s):

Mona Bahout ◽

Praveen B. Managutti ◽

Vincent Dorcet ◽

Annie Le Gal La Salle ◽

Serge Paofai ◽

...

Keyword(s):

High Temperature ◽

Anode Material ◽

Powder Diffraction ◽

Electrode Material ◽

Hydrogen Atmosphere ◽

Neutron Powder Diffraction ◽

Ni Catalyst

NiO has been incorporated into the Pr0.5Ba0.5MnO3−δ perovskite to produce in situ exsolved Ni-catalyst on the PrBaMn2O5 anode material upon heating under a hydrogen atmosphere.

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In-situ Observations of Interfacial Interactions Between Ni Catalyst and Pr Doped Ceria Support During Reduction

Microscopy and Microanalysis ◽

10.1017/s1431927610058381 ◽

2010 ◽

Vol 16 (S2) ◽

pp. 304-305

Author(s):

V Sharma ◽

R Sharma ◽

PA Crozier

Keyword(s):

Ni Catalyst ◽

Doped Ceria ◽

Interfacial Interactions ◽

Ceria Support ◽

In Situ Observations

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

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New Methods for Carbon-Carbon Bond Construction

Organic Synthesis ◽

10.1093/oso/9780199764549.003.0017 ◽

2011 ◽

Author(s):

Douglass Taber

Keyword(s):

Allylic Alcohol ◽

Ni Catalyst ◽

University Of Michigan ◽

Carbon Carbon Bond ◽

University Of Technology ◽

Duke University ◽

Michael Acceptors ◽

Leaving Groups ◽

The University

Mohammad Navid Soltani Rad of Shiraz University of Technology has shown (Tetrahedron Lett. 2007, 48, 6779) that with tosylimidazole (TsIm) activation in the presence of NaCN, primary, secondary and tertiary alcohols are converted into the corresponding nitriles. Gregory C. Fu of MIT has devised (J. Am. Chem. Soc. 2007, 129, 9602) a Ni catalyst that mediated the coupling of sp3-hybridized halides such as 3 with sp3-hybridized organoboranes such as 4, to give 5. Usually, carbanions with good leaving groups in the beta position do not couple efficiently, but just eliminate. Scott D. Rychnovsky of the University of California, Irvine has found (Organic Lett . 2007, 9, 4757) that initial protection of 6 as the alkoxide allowed smooth reduction of the sulfide and addition of the derived alkyl lithium to the amide 7 to give 8. Doubly-activated Michael acceptors such as 11 are often too unstable to isolate. J. S. Yadav of the Indian Institute of Chemical Technology, Hyderabad has shown (Tetrahedron Lett. 2007, 48, 7546) that Baylis-Hillman adducts such as 9 can be oxidized in situ, with concomitant Sakurai addition to give 12. Rather than use the usual Li or Na or K enolate, Don M. Coltart of Duke University has found (Organic Lett. 2007, 9, 4139) that ketones such as 13 will condense with amides such as 14 to give the diketone 15 on exposure to MgBr2. OEt2 and i -Pr2 NEt. Simultaneously, Gérard Cahiez of the Université de Cergy (Organic Lett. 2007, 9, 3253) and Janine Cossy of ESPCI Paris (Angew. Chem. Int. Ed. 2007, 46, 6521) reported that Fe salts will catalyze the coupling of sp2 -hybridized Grignard reagents such as 17 with alkyl halides. John Montgomery of the University of Michigan has described (J. Am. Chem. Soc. 2007, 129, 9568) the Ni-mediated regio- and enantioselective addition of an alkynes 20 to an aldehyde 19 to give the allylic alcohol 21. In a third example of sp2 - sp3 coupling, Troels Skrydstrup of the University of Aarhus has established (J. Org. Chem. 2007, 72, 6464) that Negishi coupling with alkenyl phosponates such as 23 proceeded efficiently.

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SANS Study of Chirality and Order in Liquid Crystalline Cellulose Suspensions

MRS Proceedings ◽

10.1557/proc-376-317 ◽

1994 ◽

Vol 376 ◽

Cited By ~ 3

Author(s):

W.J. Orts ◽

J.-F. Revol ◽

L. Godbout ◽

R.H. Marchessault

Keyword(s):

Magnetic Field ◽

Small Angle Neutron Scattering ◽

Liquid Crystalline ◽

Flow Direction ◽

Cellulose Microfibrils ◽

Crystalline Cellulose ◽

Magnetic Alignment ◽

Chiral Nematic ◽

Short Period

ABSTRACTSmall angle neutron scattering, SANS, was used to describe the magnetic alignment and in situ shear ordering of polyelectrolytic, liquid crystalline cellulose microfibrils in aqueous (D2O) suspension. In a 2.4 Tesla magnetic field, microfibril suspensions exhibit anisotropic chiral nematic (cholesteric) ordering in which the distance between nematic planes along the cholesteric axis is shorter than between rods within a nematic plane. This is consistent with the hypothesis that cellulose microfibrils are helically twisted rods. During shear, the SANS interference peaks perpendicular to the flow direction sharpen with increasing shear rate. Yet, the highest degree of alignment (for microfibrils with axial ratios of ~45) was observed a short period after the cessation of shear flow.

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In-situ magnetic alignment model for additive manufacturing of anisotropic bonded magnets

Additive Manufacturing ◽

10.1016/j.addma.2021.102096 ◽

2021 ◽

Vol 46 ◽

pp. 102096

Author(s):

Abhishek Sarkar ◽

M. Parans Paranthaman ◽

Ikenna C. Nlebedim

Keyword(s):

Additive Manufacturing ◽

Magnetic Alignment ◽

Alignment Model

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