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.

Interaction of Tyrosine-, Tryptophan-, and Lysine-Containing Polypeptides with Single-Wall Carbon Nanotubes and Its Relevance for the Rational Design of Dispersing Agents

Abstract: The polypeptides poly-l-(Trp,Lys·HBr) (Trp/Lys·HBr = n/m) and poly-l-(Tyr,Lys·HBr) (Tyr/Lys·HBr = n/m) were tested as dispersing agents for single-wall carbon nanotubes (SWCNTs) for n/(n+m) values of 0, 0.2, and 1. Best results were obtained for the two copolymers, illustrating the importance of using amphiphilic dispersing agents. The dispersion effect is 3.5 times higher for the copolymer containing tryptophan, indicating a stronger interaction of the tryptophan residue with the SWCNTs compared to tyrosine. The degrees of debundling of the SWCNTs and the apparent binding of the polypeptides with the SWCNTs are analyzed by atomic force microscopy for the different dispersions. The interactions of the aromatic amino acid residues with the SWCNTs are further probed by using optical absorbance and fluorescence spectroscopy.

The Electrocatalytic Properties of Arc‐MWCNTs and Associated ‘Carbon Onions’

Abstract: For the first time we report on the electrochemical characteristics of nanometer sized polyhedral graphite onions dispersed amongst arc-MWCNTs. These are formed during the electric arc discharge method of producing ultrapure MWCNTs (arc-MWCNTs). The carbon onions are randomly dispersed amongst the arc-MWCNTs which are produced with very little amorphous carbon deposits or other unwanted impurities and are formed as closed-ended tubes. By comparison with commercially available open-ended hollow-tube multiwalled carbon nanotubes made using the chemical vapor deposition method (cvd-MWCNTs), a glassy carbon electrode (GCE), an edge-plane pyrolytic graphite electrode (eppg) and basal plane pyrolytic graphite (bppg) electrode, we can speculate that it is the edge-plane-like defect sites that are the electroactive sites responsible for the apparent ‘electrocatalysis’ seen with a wide range of analytes including: ferrocyanide, ruthenium hexaamine(III), nicotinamide adenosine dinucleotide (NADH), epinephrine, norepinephrine, cysteine, and glutathione. The arc-MWCNTs themselves are produced as closed-ended tubes with very few, if any, edge-plane-like defect sites evident in their HRTEM characterization. Therefore we speculate that it is the carbon onions dispersed amongst the arc-MWCNTs which have incomplete graphite shells or a rolled-up ‘Swiss-roll’ structures that posses the edge-plane-like defect sites and are responsible for the observed voltammetric responses. Carbon onions are no more or no less ‘electrocatalytic’ than open-ended MWCNTs which in turn are no more electrocatalytic than an eppg electrode. As the carbon onions are ubiquitous in MWCNTs formed using the arc-discharge method the authors advise that caution should be taken before assigning any electrocatalytic behavior to the MWCNTs themselves as any observed electrocatalysis likely arises from the carbon onion impurities.

Mono(η-cyclopentadienyl)benzamidinato alkyl compounds of titanium and zirconium

Abstract: The compounds [Zr(η-C5H5){CPh(NSiMe3)2}2Cl], [{Zr(η-C5H5)[CPh(NSiMe3)2]Cl}2{µ-CPh(NSiMe3)2}][{Zr(η-C5H5)[CPh(NSiMe3)2]Cl}2(µ-O)], [Zr(η-C5R5){CPh(NSiMe3)2}(CH2Ph)Cl](R = H or Me), [Zr(η-C5R5){CPh(NSiMe3)2}(CH2Ph)2](R = H or Me) and [M(η-C5R5){CPh(NSiMe3)2}Me2](M = Zr, R = H or Me; M = Ti, R = H have been synthesized and the crystal structures of three of them) determined.

Catalytic gas conversion method

Abstract: A method for selectively oxygenating methane to carbon monoxide and hydrogen by bringing the reactant gas mixture at a temperature of at least 600° C. into contact with a sold catalyst which is either: a) a catalyst of the formula M x M' y O z where: M is at least one element selected from Mg, B, Al, Ln, Ga, Si, Ti, Zr and Hf, Ln is at least one member of lanthanum and the lanthanide series of elements, M'is a d-block transition metal, and each of the ratios x/z and y/z and (x+y)/z is independently from 0.1 to 8; or b) an oxide of a d-block transition metal; or c) a d-block transition metal on a refractory support; or d) a catalyst formed by heating a) or b) under the conditions of the reaction or under non-oxidizing conditions.

Single-shell carbon nanotubes of 1-nm diameter

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.

Chemistry and properties of nanocrystals of different shapes.

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

Carbon Nanotubes: Present and Future Commercial Applications

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.

Nanoparticle therapeutics: an emerging treatment modality for cancer

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.

Chemistry of Carbon Nanotubes

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