Asymtetric synthesis of alpha-amino-acids by thestrecker synthesis
Asymmetric synthesis of alpha-amino acids by strecker synthesis, including production of optically active l-aniline
STRECKER SYNTHESIS↗
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Asymmetric synthesis of alpha-amino acids by the strecker synthesis.
Asymmetric synthesis of alpha-amino acids by strecker synthesis, including production of optically active l-analine
AMINO ACID↗
Fundamental studies on the synthesis of heat- resistant polymers. The synthesis and evaluation of polymeric Schiff bases by bis- Schiff base exchange reactions Progress report no. 6, 31 Jan. - 15 Sep. 1965
Synthesis and evaluation of monomers for synthesis of heat resistant polymers - polymer chemistry
POLYMER CHEMISTRY↗
Optical network synthesis using birefringent crystals. V - Synthesis of lossless networks containing equal-length crystals and compensators
Optical network synthesis using birefringent crystals - synthesis of lossless networks containing equal length crystals and compensators
ELECTRO-OPTICS↗
Rapid, facile synthesis of conjugated polymer zwitterions in ionic liquids
Ionic liquids (ILs) were utilized for the rapid air-stable Suzuki polymerization of polar zwitterionic thiophene monomers, precluding the need for volatile organic solvents, phosphine ligands and phase transfer catalysts typically used in conjugated polymer synthesis.
solar (photovoltaic), charge transport, materials ↗
Chemical Synthesis of 3D Graphene-Like Cages for Sodium-Ion Batteries Applications
Sodium (Na) super ion conductor structured Na3V2(PO4)3 (NVP) is extensively explored as cathode material for sodium-ion batteries (SIBs) due to its large interstitial channels for Na+ migration. The synthesis of 3D graphene-like structure coated on NVP nanoflakes arrays via a one-pot, solid-state reaction in molten hydrocarbon is reported. The NVP nanoflakes are uniformly coated by the in situ generated 3D graphene-like layers with the thickness of 3 nm. As a cathode material, graphene covered NVP nanoflakes exhibit excellent electrochemical performances, including close to theoretical reversible capacity (115.2 mA h g-1 at 1 C), superior rate capability (75.9 mA h g-1 at 200 C), and excellent cyclic stability (62.5% of capacity retention over 30000 cycles at 50 C). Furthermore, the 3D graphene-like cages after removing NVP also serve as a good anode material and deliver a specific capacity of 242.5 mA h g-1 at 0.1 A g-1. The full SIB using these two cathode and anode materials delivers a high specific capacity (109.2 mA h g-1 at 0.1 A g-1) and good cycling stability (77.1% capacity retention over 200 cycles at 0.1 A g-1).
Cao, Xinxin↗
Flame-based synthesis and in situ functionalization of palladium alloy nanoparticles
Not provided.
Engineering↗
Synthesis Strategies for Ultrastable Zeolite GIS Polymorphs as Sorbents for Selective Separations
Abstract Designing zeolites with tunable physicochemical properties can substantially impact their performance in commercial applications, such as adsorption, separations, catalysis, and drug delivery. Zeolite synthesis typically requires an organic structure‐directing agent to produce crystals with specific pore topology. Attempts to remove organics from syntheses to achieve commercially viable methods of preparing zeolites often lead to the formation of impurities. Herein, we present organic‐free syntheses of two polymorphs of the small‐pore zeolite P (GIS), P1 and P2. Using a combination of adsorption measurements and density functional theory calculations, we show that GIS polymorphs are selective adsorbents for H 2 O relative to other light gases (e.g., H 2 , N 2 , CO 2 ). Our findings refute prior theoretical studies postulating that GIS‐type zeolites are excellent materials for CO 2 separation/sequestration. We also show that P2 is significantly more thermally stable than P1, which broadens the operating conditions for GIS‐type zeolites in commercial applications and opens new avenues for exploring their potential use in processes such as catalysis.
Oleksiak, Matthew D.↗
Synthesis and Characterization of TiC Nanofibers Obtained via a Modified Carbothermal Process
Not provided.
Crystallography↗
Effect of Synthesis Method Using Varying Types of Micropore Level Sulfur Infiltration on Electrochemical Performance in Lithium–Sulfur Batteries
The role of physically restrained, noncrystalline sulfur species in rechargeable lithium–sulfur batteries is examined by electrochemical and high‐resolution material characterizations. Carbon–sulfur composites are created by melting and sublimation of sulfur in an isochoric reactor via the autogenic process. These noncrystalline sulfur cathodes demonstrate a high specific capacity of ≈1000 Ah kg −1 after 100 cycles with a gravimetric current of 557 A kg −1 . Interestingly, this high‐performance sulfur allotrope lacks a long‐range structural order: high‐resolution X‐ray diffraction, performed at the Advanced Photon Source, indicates the lack of crystalline (i.e., orthorhombic or monoclinic) sulfur in the nanoscale domain. Electrochemical and material characterizations suggest that noncrystalline sulfur is a consequence of synthesis and not necessarily evidence of electrochemical efficacy. Rather, a high rate capacity depends on sulfur distribution, in turn, controlled by synthesis pathway. At higher sulfur content, the performance of carbon–sulfur composites is limited by the available surface area in which crystalline sulfur coincides with reduced gravimetric capacity and greater charge transport impedance, suggesting suboptimal sulfur containment.
Dysart, Arthur Dence↗
Comprehensive study of a versatile polyol synthesis approach for cathode materials for Li-ion batteries
Abstract not provided
Chung, Hyeseung↗
Metal organic framework-mediated synthesis of potassium-promoted cobalt-based catalysts for higher oxygenates synthesis
Syngas to higher oxygenates conversion was carried out on a series of potassium-promoted cobalt-based catalysts. Catalysts with different potassium composition were prepared by metal organic framework-mediated synthesis, which is the calcination of the ZIF-67 metal organic framework (MOF). Cobalt skeleton structure that originated from the MOF is preserved after the calcination. The calcined catalysts consist of Co 3 O 4 nanoparticles and surface carbon. The catalysts were reduced by H 2 /He prior to the reaction. CO hydrogenation was carried out at various temperatures (270 °C, 300 °C and 325 °C) and at 40 bar, with H 2 /CO = 1/1. The formation of methane and higher hydrocarbons is suppressed by potassium, and cobalt carbide is formed from metallic cobalt during the reaction. Thus, the K-promoted cobalt based catalyst synthesized by the MOF-mediated synthesis shows higher selectivity to ethanol, acetaldehyde and higher oxygenates, even at high temperatures.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Synthesis of graphene-like carbon from biomass pyrolysis and its applications
Two-dimensional graphene materials attracted much attention worldwide because of their superior performance in electronic devices, sensors, and energy storage. However, its application is limited by high cost and insufficient production. The work to find out a simple and environmentally friendly process is highly needed. Designed pyrolysis of biomass precursors can derive graphene-like materials. This review summarizes some typical preparation processes for graphene-like materials synthesis from biomass carbonization via pyrolysis, including salt-based activation, template-based confinement, chemical blowing, coupling with hydrothermal carbonization pretreatment, post exfoliation, and some other methods. The operation of these methods and the performance of obtained graphene-like materials were closely highlighted. The scalability of the techniques and the applications of the biomass graphene-like carbon were also discussed. Some advanced characterization methods, such as SEM, TEM, AFM, Raman, and XPS to determine the graphene-like structure and graphitization degree were also discussed. In the end, some current challenges and future perspectives of the synthesis of these graphene-like materials were concluded.
pyrolysis, graphene, biomass, application, scalabi↗