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.

Single-shell carbon nanotubes of 1-nm diameter

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

Chemistry and properties of nanocrystals of different shapes.

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.

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Carbon Nanotubes: Present and Future Commercial Applications

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.

Nanoparticle therapeutics: an emerging treatment modality for cancer

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

Chemistry of Carbon Nanotubes

Silicon containing ferrocenyl phosphane ligands

The synthesis and characterisation of one-dimensional (1D) crystals that have a well-specified chemistry, size and crystal structure have presented a formidable challenge for materials chemistry and analysis. We report here the filling of single (SWNTs) and double walled carbon nanotubes (DWNTs) by two different p-block halides, TlCl and PbI2. The nanotubes were produced either by the arc synthesis [1] or by a CVD method [2], based on the reduction of a Mg0.9Co0.1O solid solution by a hydrogen-methane mixture. In the case of TlCl, the structure of the crystals observed inside the tubes were all found to be derived from the rocksalt form and bilayer crystals were observed which exhibited reduced coordination relative to the fcc structure, as determined from high resolution transmission electron microscopy (HRTEM). In contrast, the crystal structure of bulk TlCl is a CsCl type structure. These results are consistent with the recently reported reduced coordination KI crystals formed within SWNTs [3]. In the case of PbI2 (i.e. with the CdCl2 structure), the use of HRTEM images combined with image simulations was used to confirm the partially reduced coordination of Pb atoms within the SWNT and DWNT confined 1D crystals.

1D P-Block Halide Crystals Confined into Single Walled Carbon Nanotubes

We studied thepressuredeveloped bythediaphragm inresponse tostimulation of thephrenic nerveintheneck, inthree normal men. Whenthephrenic was electrically stimulated atincreasing frequencies thediaphragm responded byincreasing transdiaphragmatic pressure to give a frequency-pressure curvesimilar to,thefrequency-force curveforother skeletal muscles. Thesubjects thenbreathed through an ispiratory resistance foraslong aspossible andthe frequency-pressure curve was repeated. Itl was foundthatthediaphragm developed lowfre- quencyfatigue, inthesame way aspreviously described forother muscles. We conclude thatthe diaphragm hascontractile properties similar tothose ofother skeletal muscles. Lowfrequency fatigue ofthediaphragm could contribute torespiratory failure inpatients withlungdisease. Thediaphragm isthemostimportant muscle of respiration. Therehavebeenfewstudies ofthe contractile properties ofthis muscle although the response toelectrical stimulation hasbeenstudied inanimals,' andthehumandiaphragm hasbeen investigated invitro.2 3Thesestudies suggested thatthe contractile characteristics of the diaphragm weresimilar tothose ofother skeletal muscles. However, there hasbeennoinvivostudy inman.Techniques arenowwellestablished for measuring theforce ofisometric contraction ofa large proximal muscle(quadriceps) anda small distal muscle(adductor pollicis) after electrical stimulation at different frequencies-the fre- quency-force curve.4 Thesametechnique has

Contractile properties andfatigue ofthe diaphragm inman

The compounds [{(η-C5H5)(µ-{η1:η5-C5H4})Mo}2] and [{(η-C5H5)(µ-[η1:η5-C5H4])WH}2] have been prepared; the systems [M(η-C5H5)X2](M = Mo or W, X2= Cl2 or O)–NaHg deoxygenate epoxides catalytically.

Malcolm L. H. Green

Papers

Silicon containing ferrocenyl phosphane ligands

1D P-Block Halide Crystals Confined into Single Walled Carbon Nanotubes

Contractile properties andfatigue ofthe diaphragm inman

Photoinduced synthesis of binuclear molybdenocene and tungstenocene derivatives- catalytic deoxygenation of epoxides by metallocenes

Synthesis of MCM-41 frameworks incorporating oxygen-sulphur derivates of molybdenum and tungsten