Fast and Selective Dehydrogenative C–H/C–H Arylation Using ...
A fast and site-selective biaryl synthesis via dehydrogenative C–H/C–H arylation in a ball mill was developed. In this paper, both electron-deficient oximes and electron-rich anilides quickly and under mild conditions provided arylation with various arenes to give the biaryl products in high-level selectivity. Given the solventless mechanochemical conditions, the transformation …
Ball milling: an efficient and green approach for ...
Ball milling has been fruitfully utilized in the synthesis of various (elemental) organic scaffolds, including common drugs or drug candidates. However, the utilization of ball milling in asymmetric organic synthesis has not …
How Mechanical and Chemical Features Affect the Green ...
This work investigated the chemical and mechanical factors that affect cyclocondensation reactions in a ball mill. Chemical characteristics such as the use or non-use of a catalyst, amount of catalyst and reactants, and product formation, as well as the yield and mechanical factors such as rotation frequency and the number, diameter, and material of the milling balls were …
Organic & Biomolecular Chemistry - ResearchGate
Biomolecular Chemistry COMMUNICATION Cite this: Org. Biomol. Chem., 2019, 17, 1722 Received 24th July 2018, Accepted 3rd September 2018 …
Flow behavior and syneresis of ball milled rice starch and ...
Rice starch modification by ball milling. Starch was ground in a planetary ball mill model PM 100 manufactured by Retsch (Retsch , Germany) with zirconium jar (500 mL) and balls (diameter: 5 mm) at different levels of milling energy within the range 0.26–4.08 kJ/g (equivalent to 5.3–87.1 min of milling time) and constant rotational ...
A Red‐Phosphorous‐Assisted Ball‐Milling Synthesis of Few ...
0D MXene nanodots of 6 nm in lateral size and 2–5 nm in thinkness were prepared from 2D MXene with the help of red phosphorous with a ball-milling process. Abstract Layered two-dimensional (2D) early transition metal carbides (MXenes) are a new class of 2D materials with established activity for electrochemical energy conversion and storage.
An Overview of High-energy Ball Milled Nanocrystalline ...
10%This book presents a comprehensive overview of the nanocrystalline Al based alloys as prepared using high-energy ball milling (HEBM). It discusses the influence of HEBM parameters on grain refinement and examines methods for the consolidation of nanocrystalline Al powders; further, it reviews the effects of various processing parameters on the final …
Nonconductive layered hexagonal boron nitride exfoliation ...
N2 - Boron nitride (h-BN), which is an isoelectronic analogue of graphite, has received immense attention due to its unique physical and chemical properties. Numerous methods have been developed to isolate few-layered h-BN nanosheets. These include chemical vapour deposition, solution-based exfoliation and ball-milling amongst others.
Preparation and characterization of ball‐milled Nafion ...
Preparation and characterization of ball-milled Nafion® powders for membrane applications. Shawn D. Haynes, Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118. ... traces of iron from the milling materials are shown to be present through transmission electron microscopy analysis of the ...
Combined pretreatment using alkaline hydrothermal and ball ...
Concerning maximal recovery of glucose and xylose, 1.5% NaOH was impregnated in the system and subsequent ball milling treatment was employed to improve the conversion yield. The effects of combined hydrothermal and ball milling pretreatments were evaluated by chemical composition changes by using FT-IR, WAXD and morphological alterations by SEM.
Silicon nanoparticles with chemically tailored surfaces ...
Department of Chemical and Biomolecular Engineering, Tulane University, 300 Lindy Boggs, 6283 St Charles Ave, New Orleans, LA 70118, USA. ... The mechanochemical synthesis of silicon nanoparticles via high-energy ball milling produces a variety of covalently bonded surfaces depending on the nature of the organic liquid used in the milling process.
Manufacturers, Suppliers, Exporters & Importers from the ...
Contact Supplier. Compare. Huahong lab ball mill's application: 1. Chinaware ball mill is a mineral processing machine for milling the materials into powders after they are crushed. 4. When the cylinder rotates, the centrifugal force produced causes the steel balls to impact and grind the materials in the ball mill.
Upcycling chitin-containing waste into organonitrogen ...
After ball milling (700 rpm), solid chitinous samples featured weaker carbon peaks at 20.3 ppm (C-8) and 170.8 ppm (C-7), which belonged to the acetamido group, and two individual chemical shift peaks belonging to C-3 and C-5 disappeared.
Robust Buchwald–Hartwig amination enabled by ball …
The ball milling process is known to increase the specific surface area of SWCNTs through structural defects. To ascertain such changes in surface area, N 2 gas adsorption experiments were...
Direct Combustion Synthesis of Silicon Carbide Nanopowder ...
Direct synthesis of silicon carbide (SiC) nanopowders (size 50–200 nm, BET ~20 m 2 /g) in Si–C system is conducted in an inert atmosphere (argon) using a self-propagating high-temperature synthesis (SHS) approach. A preliminary short-term (e.g., minutes) high-energy ball milling (HEBM) of the initial mixture, which involves pure Si and C powders, is used to …
Spectrochimica Acta Part A: Molecular and Biomolecular ...
Note that this compound (prepared by ball milling of LiBH 4 and KBH 4 in a ratio of 2:1 [37]) also contains an excess of LiBH 4. Table 1 List of the borohydrides whom IR spectra are included in the data collection. For each compound, the filename and the reference from where the IR spectrum was taken (when available) are shown.
Analysis of structural transformation in nanocrystalline ...
In the present work, ultra-fine powder of oxide dispersion strengthened Alloy 617 was synthesized by high energy ball milling. Milling parameters such …
Upcycling chitin-containing waste into organonitrogen ...
Ball milling (Fritsch, Pulverisette 7) was performed at 300 to 700 rpm and 4 to 12 cycles. One cycle consisted of 10 min of grinding and 5 min of resting. After grinding, distilled water (10 mL) was added into the ball-mill chambers and rotated at low speed (200 rpm) for 5 …
Robust Buchwald–Hartwig amination enabled by ball …
Robust Buchwald–Hartwig amination enabled by ball-milling Q. Cao, W. I. Nicholson, A. C. Jones and D. L. Browne, Org. Biomol.Chem., 2019, 17, 1722 DOI: 10.1039/C8OB01781F This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further …
Preparation and characterization of ball‐milled Nafion ...
A method for producing Nafion® powder from commercially available pellets, and using this powder to produce membranes, is described. A description of particle size distribution, chemical composition, and thermal properties of Nafion® powders prepared by high-energy ball milling of pellets is given.
Kinetic Energy Dose as a Unified Metric for Comparing Ball ...
To account for the operation of the ball milling with multiple balls as the grinding medium, a yield coefficient (φ b) needs to be introduced in (5), rendering (6) that provides the energy dissipated by the impact of one ball against the grinding jar wall in a system with multiple balls (Burgio et al., 1991).
Ball Milling Pretreatment of Oil Palm Biomass for ...
Oil palm biomass, namely empty fruit bunch and frond fiber, were pretreated using a planetary ball mill. Particle sizes and crystallinity index values of the oil palm biomass were significantly reduced with extended ball mill processing time. The treatment efficiency was evaluated by the generation of glucose, xylose, and total sugar conversion yields from the …
Enhancement of ball-milling on pyrite/zero-valent iron for ...
As showed in Fig. S2, compared with raw FeS 2, Fe 0, mixture of FeS 2 and Fe 0 without ball milling processes, the ball-milled FeS 2 and FeS 2 /Fe 0 showed better performance while Fe 0 showed decreased IMI removal rate. This is probably because the ball milling processes increase the oxides layers of Fe 0 (This was evidenced by no identified Fe 0 XPS …
production of nanoparticles using ball mill
Aug 25, 2011· First, water-dispersible nanoparticles of Boc-protected amino acid were prepared by the method of wet grinding using planetary ball mills . In the presence of PEG as a dispersant, Boc-amino acid was ground with zirconia beads in water using a planetary ball mill for 2 hours at room temperature. Chat Now
ORCID
Organic & Biomolecular Chemistry 2021 | Journal article DOI: 10.1039/d1ob00453k Part of ISSN: 1477-0520 Part of ISSN: 1477 ... Solvent-Free Cross-Dehydrogenative Coupling Reactions under High Speed Ball-Milling Conditions Applied to the Synthesis of Functionalized Tetrahydroisoquinolines. The Journal of Organic Chemistry 2011-11-04 ...
Melatonin: Regulation of Biomolecular Condensates in ...
Biomolecular condensates are membraneless organelles (MLOs) that form dynamic, chemically distinct subcellular compartments organizing macromolecules such as proteins, RNA, and DNA in unicellular prokaryotic bacteria and complex eukaryotic cells. Separated from surrounding environments, MLOs in the nucleoplasm, cytoplasm, and …
Inward lithium-ion breathing of hierarchically porous ...
mechanical ball milling, laser pyrolysis, chemical vapour deposition, solvothermal method and two-step thermal annealing/acid etching process. These materials have shown improved cycle life, capacity retention and rate performance. Similarly, the Si/C composites, wherein the carbon moieties serve as a cushion for the volume change and provide ...
Enhanced hydrogen storage properties of MgH2 with numerous ...
Na 2 Ti 3 O 7 nanotubes (NTs) with a uniform diameter of 10 nm and Na 2 Ti 3 O 7 nanorods (NRs) with a diameter of 100–500 nm were synthesized via a hydrothermal method and a solid-state method, respectively, and then introduced into MgH 2 by ball milling to catalyze the hydrogenation