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Malcolm L. H. Green

Bio: Malcolm L. H. Green is an academic researcher from University of Oxford. The author has contributed to research in topics: Carbon nanotube & Cyclopentadienyl complex. The author has an hindex of 82, co-authored 800 publications receiving 31121 citations. Previous affiliations of Malcolm L. H. Green include Gas Technology Institute & University of Illinois at Urbana–Champaign.


Papers
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Journal ArticleDOI
TL;DR: In this paper, the formation of all surface 4:4 co-ordinated KI crystals within 1.4 nm diameter single walled carbon nanotubes (SWNT) is reported.

149 citations

Journal ArticleDOI
TL;DR: A series of Na-W-Mn/SiO 2 catalysts with different sodium, tungsten, and manganese contents (wt.%) were prepared and their catalytic performance for the oxidative coupling of methane (OCM) was evaluated in a continuous micro-reactor as discussed by the authors.
Abstract: A series of Na-W-Mn/SiO 2 catalysts with different sodium, tungsten, and manganese contents (wt.%) were prepared and their catalytic performance for the oxidative coupling of methane (OCM) was evaluated in a continuous micro-reactor. The structural properties of the catalysts have been characterised using XPS, laser Raman spectroscopy (LRS), and X-ray diffraction (XRD). The results show that the catalysts containing Na, W, and Mn between the range of 0.4–2.3, 2.2–8.9, and 0.5–3.0 wt.%, respectively, had high CH 4 conversion and high selectivity to C 2 hydrocarbons in the OCM reaction. The addition of sodium to the catalyst is believed to bring about the migration of manganese to the catalyst surface, as both elements are found in high concentrations in this area. CH 4 conversion and the selectivity to C 2 H 4 are closely related to the surface Mn concentration of the catalysts. Both Na-O-Mn and Na-O-W act as the active centres of the catalysts for the oxidative coupling of methane. The catalyst surface is mainly covered with Na and O, while the Mn and W are present in the sub-surface of the catalyst. There is a synergic effect of sodium, tungsten, and manganese components, and the Na 2 W 2 O 7 crystalline phase is active for the oxidative coupling of methane.

145 citations

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TL;DR: The CBC method as discussed by the authors is based on an elementary molecular orbital analysis of the bonding involving the central atom (M), with the various interactions being classified according to the number of electrons that each neutral ligand contributes to the bonding orbital.
Abstract: The Covalent Bond Classification (CBC) method provides a means to classify covalent molecules according to the number and types of bonds that surround an atom of interest. This approach is based on an elementary molecular orbital analysis of the bonding involving the central atom (M), with the various interactions being classified according to the number of electrons that each neutral ligand contributes to the bonding orbital. Thus, with respect to the atom of interest (M), the ligand can contribute either two (L), one (X), or zero (Z) electrons to a bonding orbital. A normal covalent bond is represented as M–X, whereas dative covalent bonds are represented as either M←L or M→Z, according to whether the ligand is the donor (L) or acceptor (Z). A molecule is classified as [MLlXxZz] according to the number of L, X, and Z ligand functions that surround M. Not only does the [MLlXxZz] designation provide a formal classification of a molecule, but it also indicates the electron configuration, the valence, and t...

142 citations

Journal ArticleDOI
TL;DR: In this article, the synthesis of high surface area molybdenum carbides from butane and butane has been studied via temperature-programmed reaction (TPRe), X-ray diffraction (XRD), scanning electron microscopy (SEM), 13C solid-state NMR, infrared (IR), and Raman spectroscopy (LR).
Abstract: The synthesis of high surface area molybdenum carbides from molybdenum oxide and butane has been studied via temperature-programmed reaction (TPRe), X-ray diffraction (XRD), scanning electron microscopy (SEM), 13C solid-state NMR, infrared (IR), and Raman spectroscopy (LR) The molybdenum oxygen/carbon system passes through four phase transitions before transforming into the pure Mo2C carbide Carbon exists in two forms within high surface area molybdenum carbide The initially produced molybdenum carbide has a face-centered-cubic (fcc) structure but is gradually converted into the hexagonal-close-packed (hcp) structure with increasing carburization temperature, and eventually at high temperature coke is deposited During the early stages, MoO3 is reduced by H2, but at higher temperatures, butane also takes part in the reduction and, besides being consumed in the formation of carbide, is catalytically converted into methane, ethane, propane, and benzene The high surface area of the molybdenum carbide mat

141 citations

Journal ArticleDOI
TL;DR: In this article, trasonic irradiation of gallium metal with di-iodine and alkyl iodides, RI, rapidly gives high yields of [RGaI2] via a reactive intermediate mate.

138 citations


Cited by
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Journal ArticleDOI
Sumio Iijima1, Toshinari Ichihashi1
17 Jun 1993-Nature
TL;DR: In this article, the authors reported the synthesis of abundant single-shell tubes with diameters of about one nanometre, whereas the multi-shell nanotubes are formed on the carbon cathode.
Abstract: CARBON nanotubes1 are expected to have a wide variety of interesting properties. Capillarity in open tubes has already been demonstrated2–5, while predictions regarding their electronic structure6–8 and mechanical strength9 remain to be tested. To examine the properties of these structures, one needs tubes with well defined morphologies, length, thickness and a number of concentric shells; but the normal carbon-arc synthesis10,11 yields a range of tube types. In particular, most calculations have been concerned with single-shell tubes, whereas the carbon-arc synthesis produces almost entirely multi-shell tubes. Here we report the synthesis of abundant single-shell tubes with diameters of about one nanometre. Whereas the multi-shell nanotubes are formed on the carbon cathode, these single-shell tubes grow in the gas phase. Electron diffraction from a single tube allows us to confirm the helical arrangement of carbon hexagons deduced previously for multi-shell tubes1.

8,018 citations

Journal ArticleDOI
TL;DR: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties are equally important.
Abstract: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties * To whom correspondence should be addressed. Phone, 404-8940292; fax, 404-894-0294; e-mail, mostafa.el-sayed@ chemistry.gatech.edu. † Case Western Reserve UniversitysMillis 2258. ‡ Phone, 216-368-5918; fax, 216-368-3006; e-mail, burda@case.edu. § Georgia Institute of Technology. 1025 Chem. Rev. 2005, 105, 1025−1102

6,852 citations

Journal ArticleDOI
01 Feb 2013-Science
TL;DR: Although not yet providing compelling mechanical strength or electrical or thermal conductivities for many applications, CNT yarns and sheets already have promising performance for applications including supercapacitors, actuators, and lightweight electromagnetic shields.
Abstract: Worldwide commercial interest in carbon nanotubes (CNTs) is reflected in a production capacity that presently exceeds several thousand tons per year. Currently, bulk CNT powders are incorporated in diverse commercial products ranging from rechargeable batteries, automotive parts, and sporting goods to boat hulls and water filters. Advances in CNT synthesis, purification, and chemical modification are enabling integration of CNTs in thin-film electronics and large-area coatings. Although not yet providing compelling mechanical strength or electrical or thermal conductivities for many applications, CNT yarns and sheets already have promising performance for applications including supercapacitors, actuators, and lightweight electromagnetic shields.

4,596 citations

Journal ArticleDOI
TL;DR: The features of nanoparticle therapeutics that distinguish them from previous anticancer therapies are highlighted, and how these features provide the potential for therapeutic effects that are not achievable with other modalities are described.
Abstract: Nanoparticles — particles in the size range 1–100 nm — are emerging as a class of therapeutics for cancer. Early clinical results suggest that nanoparticle therapeutics can show enhanced efficacy, while simultaneously reducing side effects, owing to properties such as more targeted localization in tumours and active cellular uptake. Here, we highlight the features of nanoparticle therapeutics that distinguish them from previous anticancer therapies, and describe how these features provide the potential for therapeutic effects that are not achievable with other modalities. While large numbers of preclinical studies have been published, the emphasis here is placed on preclinical and clinical studies that are likely to affect clinical investigations and their implications for advancing the treatment of patients with cancer.

3,975 citations

Journal ArticleDOI
TL;DR: Department of Materials Science, University of Patras, Greece, Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, and Dipartimento di Scienze Farmaceutiche, Universita di Trieste, Piazzale Europa 1, 34127 Triesteadays.
Abstract: Department of Materials Science, University of Patras, 26504 Rio Patras, Greece, Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Avenue, 116 35 Athens, Greece, Institut de Biologie Moleculaire et Cellulaire, UPR9021 CNRS, Immunologie et Chimie Therapeutiques, 67084 Strasbourg, France, and Dipartimento di Scienze Farmaceutiche, Universita di Trieste, Piazzale Europa 1, 34127 Trieste, Italy

3,886 citations