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Disruption of vulnerable atherosclerotic plaques often leads to myocardial infarction and stroke, the leading causes of morbidity and mortality in the United States. A diagnostic method that detects early‐stage high‐risk atherosclerotic plaques could prevent these sequelae. The abundant immune cells in the arterial wall, especially inflammatory Ly‐6Chi monocytes and foamy macrophages, are indicative of plaque inflammation, and may be associated with plaque vulnerability. Hence, a new method is sought to develop that specifically targets these immune cells to offer clinically relevant diagnostic information about cardiovascular disease. Ultraselective nanoparticle targeting of Ly‐6Chi monocytes and foamy macrophages and clinically‐viable photoacoustic imaging (PAI) are combined in order to precisely and specifically image inflamed plaques ex vivo in a mouse model that mimics human vulnerable plaques histopathologically. Within the plaques, high‐dimensional single‐cell flow cytometry (13‐parameter) shows that the nanoparticles are almost‐exclusively taken up by the Ly‐6Chi monocytes and foamy macrophages that heavily infiltrate plaques. PAI identifies inflamed atherosclerotic plaques that display ≈6‐fold greater signal compared to controls (P < 0.001) 6 h after intravenous injection of ultraselective carbon nanotubes, with in vivo corroboration via optical imaging. This highly‐selective strategy may provide a targeted, noninvasive imaging strategy to accurately identify and diagnose inflamed atherosclerotic lesions. [ABSTRACT FROM AUTHOR]

The present study investigates the thermal conductivity of Al2O3 hybrid with MWCNTs (multi-walled carbon nanotubes) nanoparticles dispersed in ethylene glycol (EG) as a base fluid. Seven different nanoparticles volume fractions, namely, 0.02%, 0.04%, 0.08%, 0.1%, 0.25%, 0.5% and 0.8% at temperatures ranging from 25 °C to 50 °C of the hybrid nanofluid are prepared without using any surfactant. Transient Hot Wire method (THM) using KD2 Pro device (Decagon Devices, Inc., USA) was used to measure the thermal conductivity of the nanofluids. The results show at most about 17% thermal conductivity enhancement for 0.8% nanoparticles volume fraction at 50 °C. Two new correlations are proposed to estimate the hybrid nanofluid thermal conductivity with high accuracy. The first one is a function of the nanofluid temperature and its volume fraction and the next one, with a higher accuracy, is in effect six expressions in terms of the nanoparticles volume fraction presented at temperatures 25 °C, 30 °C, 35 °C, 40 °C, 45 °C and 50 °C. [ABSTRACT FROM AUTHOR]

Background Carbon nanotubes and nanofibers (CNT/F) are increasingly used for diverse applications. Although animal studies suggest CNT/F exposure may cause deleterious health effects, human epidemiological studies have typically been small, confined to single workplaces, and limited in exposure assessment. Objectives We conducted an industrywide cross-sectional epidemiological study of 108 workers from 12 U.S. sites to evaluate associations between occupational CNT/F exposure and sputum and blood biomarkers of early effect. Methods We assessed CNT/F exposure via personal breathing zone, filter-based air sampling to measure background-corrected elemental carbon (EC) (a CNT/F marker) mass and microscopy-based CNT/F structure count concentrations. We measured 36 sputum and 37 blood biomarkers. We used factor analyses with varimax rotation to derive factors among sputum and blood biomarkers separately. We used linear, Tobit, and unconditional logistic regression models to adjust for potential confounders and evaluate associations between CNT/F exposure and individual biomarkers and derived factors. Results We derived three sputum and nine blood biomarker factors that explained 78% and 67%, respectively, of the variation. After adjusting for potential confounders, inhalable EC and total inhalable CNT/F structures were associated with the most sputum and blood biomarkers, respectively. Biomarkers associated with at least three CNT/F metrics were 72 kDa type IV collagenase/matrix metalloproteinase-2 (MMP-2), interleukin-18, glutathione peroxidase (GPx), myeloperoxidase, and superoxide dismutase (SOD) in sputum and MMP-2, matrix metalloproteinase-9, metalloproteinase inhibitor 1/tissue inhibitor of metalloproteinases 1, 8-hydroxy-2′-deoxyguanosine, GPx, SOD, endothelin-1, fibrinogen, intercellular adhesion molecule 1, vascular cell adhesion protein 1, and von Willebrand factor in blood, although directions of associations were not always as expected. Conclusions Inhalable rather than respirable CNT/F was more consistently associated with fibrosis, inflammation, oxidative stress, and cardiovascular biomarkers. [ABSTRACT FROM AUTHOR]

Background: Recent animal studies have suggested the potential for wide-ranging health effects resulting from exposure to carbon nanotubes and nanofibers (CNT/F). To date, no studies in the US have directly examined the relationship between occupational exposure and potential human health effects.Objectives: Our goal was to measure CNT/F exposures among US workers with representative job types, from non-exposed to highly exposed, for an epidemiologic study relating exposure to early biologic effects.Methods: 108 participants were enrolled from 12 facilities across the US. Personal, full-shift exposures were assessed based on the mass of elemental carbon (EC) at the respirable and inhalable aerosol particle size fractions, along with quantitatively characterizing CNT/F and estimating particle size via transmission electron microscopy (TEM). Additionally, sputum and dermal samples were collected and analyzed to determine internal exposures and exposures to the hands/wrists.Results: The mean exposure to EC was 1.00 μg/m3 at the respirable size fraction and 6.22 μg/m3 at the inhalable fraction. Analysis by TEM found a mean exposure of 0.1275 CNT/F structures/cm3, generally to agglomerated materials between 2 and 10 μm. Internal exposures to CNT/F via sputum analysis were confirmed in 18% of participants while ∼70% had positive dermal exposures.Conclusions: We demonstrated the occurrence of a broad range of exposures to CNT/F within 12 facilities across the US. Analysis of collected sputum indicated internal exposures are currently occurring within the workplace. This is an important first step in determining if exposures in the workforce have any acute or lasting health effects. [ABSTRACT FROM AUTHOR]

Few trends in science have generated as much discussion as its politicization. This occurs when an actor emphasizes the inherent uncertainty of science to cast doubt on the existence of scientific consensus. In this article, we offer a framework that generates predictions about when communications can be used to counteract politicization efforts aimed at novel energy technologies. We then present evidence from nationally representative survey experiments to demonstrate how warnings to dismiss future politicization and corrections to ignore past claims can counteract politicization's effects. The results provide novel insights about science communication in a politicized era and offer a blueprint on which future work can build. [ABSTRACT FROM AUTHOR]

Recent evidence has suggested the potential for wide-ranging health effects that could result from exposure to carbon nanotubes (CNT) and carbon nanofibers (CNF). In response, the National Institute for Occupational Safety and Health (NIOSH) set a recommended exposure limit (REL) for CNT and CNF: 1 μg m−3 as an 8-h time weighted average (TWA) of elemental carbon (EC) for the respirable size fraction. The purpose of this study was to conduct an industrywide exposure assessment among US CNT and CNF manufacturers and users. Fourteen total sites were visited to assess exposures to CNT (13 sites) and CNF (1 site). Personal breathing zone (PBZ) and area samples were collected for both the inhalable and respirable mass concentration of EC, using NIOSH Method 5040. Inhalable PBZ samples were collected at nine sites while at the remaining five sites both respirable and inhalable PBZ samples were collected side-by-side. Transmission electron microscopy (TEM) PBZ and area samples were also collected at the inhalable size fraction and analyzed to quantify and size CNT and CNF agglomerate and fibrous exposures. Respirable EC PBZ concentrations ranged from 0.02 to 2.94 μg m−3 with a geometric mean (GM) of 0.34 μg m−3 and an 8-h TWA of 0.16 μg m−3. PBZ samples at the inhalable size fraction for EC ranged from 0.01 to 79.57 μg m−3 with a GM of 1.21 μg m−3. PBZ samples analyzed by TEM showed concentrations ranging from 0.0001 to 1.613 CNT or CNF-structures per cm3 with a GM of 0.008 and an 8-h TWA concentration of 0.003. The most common CNT structure sizes were found to be larger agglomerates in the 2-5 μm range as well as agglomerates >5 μm. A statistically significant correlation was observed between the inhalable samples for the mass of EC and structure counts by TEM (Spearman ρ = 0.39, P < 0.0001). Overall, EC PBZ and area TWA samples were below the NIOSH REL (96% were <1 μg m−3 at the respirable size fraction), while 30% of the inhalable PBZ EC samples were found to be >1 μg m−3. Until more information is known about health effects associated with larger agglomerates, it seems prudent to assess worker exposure to airborne CNT and CNF materials by monitoring EC at both the respirable and inhalable size fractions. Concurrent TEM samples should be collected to confirm the presence of CNT and CNF. [ABSTRACT FROM AUTHOR]

Instrumental neutron activation analysis with both relative and k0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube certified reference material (CRM) SWCNT-1. Results obtained were evaluated using the National Institute of Standards and Technology (NIST) "Type B On Bias" approach and yielded consensus values in agreement with National Research Council Canada (NRCC) certified values for Fe, Co, Ni, and Mo and provided mass fraction values for 13 additional elements, namely, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Br, La, W, and Au. In addition, prompt γ neutron activation analysis was employed to determine mass fractions of H, B, Co, Ni, and Mo. Results of this work provide a basis for the establishment of reference values of element mass fractions in CRM SWCNT-1, thus expanding its usability for more accurate characterization and benchmarking of similar nanotechnology materials. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer-related mortality in the United States. Across the globe, people in the age group older than 50 are at a higher risk of CRC. Genetic and environmental risk factors play a significant role in the development of CRC. If detected early, CRC is preventable and treatable. Currently, available screening methods and therapies for CRC treatment reduce the incidence rate among the population, but the micrometastasis of cancer may lead to recurrence. Therefore, the challenge is to develop an alternative therapy to overcome this complication. Nanotechnology plays a vital role in cancer treatment and offers targeted chemotherapies directly and selectively to cancer cells, with enhanced therapeutic efficacy. Additionally, nanotechnology elevates the chances of patient survival in comparison to traditional chemotherapies. The potential of nanoparticles includes that they may be used simultaneously for diagnosis and treatment. These exciting properties of nanoparticles have enticed researchers worldwide to unveil their use in early CRC detection and as effective treatment. This review discusses contemporary methods of CRC screening and therapies for CRC treatment, while the primary focus is on the theranostic approach of nanotechnology in CRC treatment and its prospects. In addition, this review aims to provide knowledge on the advancement of nanotechnology in CRC and as a starting point for researchers to think about new therapeutic approaches using nanotechnology., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

On the basis of Web of Science database, through scientometrics, quantitative and qualitative research was conducted on carbon nanotubes literature produced globally. A total of 64,376 publications and 1,770,339 citations were received to these publications during 1992-2012. It was found that the number of published articles was higher in Peoples Republic of China, USA, Japan, South Korea, Germany, France, England, India, etc. The highest number of publications 10,375 (16.12%) was published in 2012. The highest number of citations 165,515 (9.35%) was received in 2005. The highest average citations per publication 498.25 was in 1992. The highest growth rate (387.50%) was observed in 1993. Overall Collaboration Coefficient (CR) was very high. [ABSTRACT FROM AUTHOR]

The seventh U.S.-Japan Joint Seminar on Nanoscale Transport Phenomena was held in Shima, Japan, from December 11 to 14, 2011. The goals of this joint seminar were to provide a critical assessment of the state of the art and future directions in the field of nanoscale transport phenomena and energy conversion processes, to foster U.S.-Japan col-laborations, and to provide international exposure to a new generation of scientists in this field Issues discussed in the joint seminar were organized in 10 topical sessions, includ-ing (1) nanoscale thermophysical measurements; (2) optical characterization; (3) thermal and molecular transport; (4) phonon transport modeling; (5) energy storage and conversion; (6) nanoscale fluidics and phase change phenomena; (7) biological and organic systems; (8) interfacial thermal transport; (9) novel thermoelectric and thermal management mate-rials; and (10) nanocarbon materials and devices. In addition to these topical sessions, the joint seminar featured an opening plenary session and a closing plenary session as well as an expert panel, where leading experts provided critical assessment of the past progress and addressed future directions in the field. In addition, an evening poster session provided opportunities for graduate and postdoc students to present their latest research results. About 35 researchers from Japan and 31 researchers from the United States participated in the meeting. The meeting was organized by S. Maruyama, K. Fushinobu, L. Shi, and J. Lukes together with about 20 other participants who served as session chairs. Summaries of dif-ferent sessions of the seminar were prepared by the session and conference chairs and are collected into this report. [ABSTRACT FROM AUTHOR]

A significant number of patents have issued to Rice University for Professor Richard Smalley's research in the field of carbon nanotubes. This article surveys the Smalley Patent Portfolio and explores valuation metrics applicable to the portfolio that an entity may want to consider when entering the carbon nanotube field. [ABSTRACT FROM AUTHOR]

As an emerging domain of risk research, nanotechnologies engender novel research questions, including how new technologies are encountered given different framing and contextual detail. Using data from a recent U.S. national survey of perceived risks ( N= 1,100), risk versus benefit framings and the specific social positions from which people encounter or perceive new technologies are explored. Results indicate that vulnerability and attitudes toward environmental justice significantly influenced risk perceptions of nanotechnology as a broad class, while controlling for demographic and affective factors. Comparative analyses of different examples of nanotechnology applications demonstrated heightened ambivalence across acceptability when risk versus benefit information was provided with application descriptions (described in short vignettes as compared to the general category 'nanotechnology,' absent of risk or benefit information). The acceptability of these nano-specific vignettes varied significantly in only some cases given indexes of vulnerability and attitudes toward environmental justice. However, experimental narrative analyses, using longer, more comprehensive descriptive passages, show how assessments of risks and benefits are tied to the systematically manipulated psychometric qualities of the application (its invasiveness and controllability), risk messaging from scientists, and the social implications of the technology with regard to justice. The article concludes with discussion of these findings for risk perception research and public policy related to nanotechnology and possibly other emerging technologies. [ABSTRACT FROM AUTHOR]

Electrochemical detection of p-nitrophenol (P-NP) using a highly sensitive and selective platform based on single-walled carbon nanotube/pyrenecyclodextrin (SWCNT/PyCD) nanohybrids is described for the first time. The electrochemical performance of the SWCNT/PyCD nanohybrid electrode was fully compared with bare glassy carbon, single-SWCNT, single-PyCD, and SWCNT/CD (without pyrene rings) electrodes. Besides the techniques of cyclic voltammetry and chronoamperometric transients, differential pulse voltammetry (DPV) has been used for the detection of P-NP without any interference from o-nitrophenol (O-NP) at the potentials of −0.80 and −0.67 V, respectively. The SWCNT/PyCD nanohybrid electrode is highly sensitive, and it shows an ultrahigh sensitivity of 18.7 μA/μM toward P-NP in contrast to the values reported previously. The detection limit (S/N= 3) of the SWCNT/PyCD nanohybrid electrode toward P-NP is 0.00086 μM (0.12 ppb), which is well below the allowed limit in drinking water, 0.43 μM, given by the U.S. Environmental Protection Agency (EPA). The analytical performance of the SWCNT/PyCD nanohybrid electrode toward P-NP is superior to the existing electrodes. [ABSTRACT FROM AUTHOR]

Despite the widespread commercial use of nanomaterials, regulators currently have a limited ability to characterize and manage risks. There is a paucity of data available on the current production and use of nanomaterials and extreme scientific uncertainty on most aspects of the risk assessment 'causal chain.' Regulatory decisions will need to be made in the near-term in the absence formal quantitative risk assessments. The article draws on examples from three different regulatory contexts-baseline data monitoring efforts of the U.S. Environmental Protection Agency and California Department of Toxic Substances Control, prioritization of risk information in the context of environmental releases, and mitigation of occupational risks-to argue for the use of decision-analytic tools in lieu of formal risk assessment to help regulatory bodies. We advocate a 'horses for courses' approach whereby existing analytical tools (such as risk ranking, multi-criteria decision analysis, and 'control banding' approaches) might be adapted to regulators' goals in particular decision contexts. While efforts to build new and modify existing tools are underway, they need greater support from funding and regulatory agencies because innovative approaches are needed for the 'extreme' uncertainty problems that nanomaterials pose. [ABSTRACT FROM AUTHOR]

Nanotechnology is touted as a transformative technology in that it is predicted to improve many aspects of human life. There are hundreds of products in the market that utilize nanostructures in their design, such as composite materials made out of carbon or metal oxides. Potential risks to consumers, to the environment, and to workers from the most common passive nanomaterial-carbon nanotubes-are emerging through scientific research. Newer more active nanostructures-such as cancer therapies and targeted drug systems-are also increasing in use and are raising similar risk concerns. Governing the risks to workers is the subject of this commentary. The Occupational Safety and Health Act of 1970 grants the Occupational Safety and Health Administration the legal authority to set occupational health standards to insure that no worker suffers material impairment of health from work. However, setting a standard to protect workers from nanotechnology risks may occur some time in the future because the risks to workers have not been well characterized scientifically. Alternative risk governances-such as dynamic oversight through stakeholder partnerships, 'soft law' approaches, and national adoption of international consensus standards-are evaluated in this article. [ABSTRACT FROM AUTHOR]

The article offers insights on some of the potential of nanotechnology in relation to environmental issues, health care and the business industry. University of Ontario graduate students James Hiller and Albert Prebus built the first electron microscope which uses electrons to explore nanotechnology. Richard Feynman introduces the concept of nanotechnology which was later defined as the small and large structures built with atom or molecule using nanorobots as its assemblers. The National Aeronautics and Space Administration (NASA) mentions that it forms objects 100-nanometer in size for devices. Synthetic silver nanowires (AGNWs) and carbon nanotubes (CNTs) for water filters are used to improve the water purification system in Pakistan and solve the problem on Escherichia coli.

Current first-line treatments for most cancers feature a short-list of highly potent and often target-blind interventions, including chemotherapy, radiation, and surgical excision. These treatments wreak considerable havoc upon non-cancerous tissue and organs, resulting in deleterious and sometimes fatal side effects for the patient. In response,this past decade has witnessed the robust emergence of nanoparticles and, more relevantly,nanoparticle drug delivery systems (DDS), widely touted as the panacea of cancer therapeutics. While not a cure, nanoparticle DDS can successfully negotiate the clinical payoff between drug dosage and side effects by encompassing target-specific drug delivery strategies. The expanding library of nanoparticles includes lipoproteins, liposomes, dendrimers, polymers, metal and metal oxide nano-spheres and -rods, and carbon nanotubes, so do the modes of delivery. Importantly, however, the pharmaco-dynamics and -kinetics of these nano-complexes remain an urgent issue and a serious bottleneck in the transition from bench to bedside. This review addresses the rise of nanoparticle DDS [ABSTRACT FROM AUTHOR]

Stroke results in the disruption of tissue architecture and is the third leading cause of death in the United States. Transplanting scaffolds containing stem cells into the injured areas of the brain has been proposed as a treatment strategy, and carbon nanotubes show promise in this regard, with positive outcomes when used as scaffolds in neural cells and brain tissues. Here, we show that pretreating rats with amine-modified single-walled carbon nanotubes can protect neurons and enhance the recovery of behavioural functions in rats with induced stroke. Treated rats showed less tissue damage than controls and took longer to fall from a rotating rod, suggesting better motor functions after injury. Low levels of apoptotic, angiogenic and inflammation markers indicated that amine-modified single-walled carbon nanotubes protected the brains of treated rats from ischaemic injury. [ABSTRACT FROM AUTHOR]

Abstract: We revealed the arrangement of single-wall carbon nanotube (SWNT) which is suitable for the adsorption of hydrogen by means of grand canonical Monte Carlo (GCMC) simulation with simple cylindrical model. Here, we calculated the amount of adsorbed hydrogen with triangular lattice (TL) and square lattice (SL) model for the bundle structure with various kinds of tube diameters (D) and inter-axis distances (R a). Our results indicate that any arrangements having smaller R a are not suitable for the storage of hydrogen and the adsorption amount of hydrogen can be achieved the target value (6 wt.% and 45 kg m−3) proposed by Department of Energy (DOE) in United States by SWNTs having larger R a at 77 K and 1 MPa. Furthermore, these results show that the best arrangement of SWNTs for the adsorption of hydrogen at this condition is TL structure having R a = 2.159 nm and D = 1.227 nm. [Copyright &y& Elsevier]

Carbon nanotubes (CNTs) are novel materials with remarkable properties; possible beneficial applications include aircraft frames, hydrogen storage, environmental sensors, electrical transmission, and many more. At the same time, precise characterization of their potential toxicity remains elusive, in part because engineered nanostructures pose challenges to existing assays, predictive models, and dosimetry. While these obstacles are surmountable, their presence suggests that scientific uncertainty regarding the hazards of CNTs is likely to persist. Traditional U.S. policy approaches implicitly pose the question: 'What level of evidence is necessary and sufficient to justify regulatory action?' In the case of CNTs, such a strategy of risk analysis is of limited immediate utility to both regulators essaying to carry out their mandates, and users of CNTs seeking to provide an appropriate level of protection to employees, customers, and other stakeholders. In contrast, the concept of anticipatory governance suggests an alternative research focus, that is: 'Given the conflicted character of the data, how should relevant actors respond?' Adopting the latter theoretical framework, this article argues that currently available data support treating CNTs 'as if' they are hazardous, while simultaneously highlighting some systemic uncertainties in many of the experiments carried out to date. Such a conclusion implies limiting exposure throughout product lifecycles, and also points to the possible applicability of various conceptual tools, such as life-cycle and multicriteria decision analysis approaches, in choosing appropriate courses of action in the face of prolonged uncertainty. [ABSTRACT FROM AUTHOR]

The NanoSafety Consortium for Carbon (NCC) is an industry-driven group formed to proactively address potential environmental, health, safety, and regulatory concerns related to the commercialization of its members' nanoscale carbon products. NCC was formed to take advantage of an offer by the EPA for a consortium of companies to providing testing regarding carbon nanotube toxicity. This article provides background on NCC's activities, purpose, and goals. [ABSTRACT FROM AUTHOR]

Model calculations are performed to predict the nature of interaction between SWNT and a tripeptide (Lys-Trp-Lys) and to calculate the binding energies and charge transfer between these two species using density functional theory. DFT calculations indicate that the interaction is of a non covalent nature. Minimal charge transfer is observed between SWNT and Lys- Trp-Lys. [ABSTRACT FROM AUTHOR]

Context: After the collapse of the World Trade Center (WTC) on 11 September 2001, a dense cloud of dust containing high levels of airborne pollutants covered Manhattan and parts of Brooklyn, New York. Between 60,000 and 70,000 responders were exposed. Many reported adverse health effects. Case presentation: In this report we describe clinical, pathologic, and mineralogic findings in seven previously healthy responders who were exposed to WTC dust on either 11 September or 12 September 2001, who developed severe respiratory impairment or unexplained radiologic findings and underwent video-assisted thoracoscopic surgical lung biopsy procedures at Mount Sinai Medical Center. WTC dust samples were also examined. We found that three of the seven responders had severe or moderate restrictive disease clinically. Histopathology showed interstitial lung disease consistent with small airways disease, bronchiolocentric parenchymal disease, and nonnecrotizing granulomatous condition. Tissue mineralogic analyses showed variable amounts of sheets of aluminum and magnesium silicates, chrysotile asbestos, calcium phosphate, and calcium sulfate. Small shards of glass containing mostly silica and magnesium were also found. Carbon nanotubes (CNT) of various sizes and lengths were noted. CNT were also identified in four of seven WTC dust samples. Discussion: These findings confirm the previously reported association between WTC dust exposure and bronchiolar and interstitial lung disease. Long-term monitoring of responders will be needed to elucidate the full extent of this problem. The finding of CNT in both WTC dust and lung tissues is unexpected and requires further study. [ABSTRACT FROM AUTHOR]

The article highlights ten patents with potential impact on the commercialization of carbon nanotubes and products incorporating carbon nanotubes. These patents include U.S. Patent No. 5,424,054, U.S. Patent No. 5,643,502 and U.S. Patent No. 5,578,543. It notes that it is difficult to predict correctly how emerging nanomaterials will be commercialized, or what patents will be relevant to actual commercial products. Moreover, it also notes that it is difficult to predict how the scope of certain patents will be interpreted, or how courts will address questions of patent validity.

Abstract: The reported hydrogen uptake of carbon nanotubes (CNTs) has been the subject of much controversy. We have measured the hydrogen uptake capacity of different types of CNTs using a volumetric measurement setup specifically-designed for CNTs. It was found that under a pressure of ∼12MPa and at room temperature, the hydrogen storage capacity of the CNTs is less than 1.7wt.%, which is far below the benchmark set for on-board hydrogen storage systems by the US Department of Energy. These results suggest that it is no longer worth investigating hydrogen uptake in pure CNTs for on-board applications. However, our recent research indicates that CNTs can be an effective additive to some other hydrogen storage materials to improve their kinetics. [Copyright &y& Elsevier]

The article investigates on the construction of the Space Elevator (SE), a thin ribbon of carbon nanotubes stretching between an Earth station anchor and a satellite in low orbit, in the U.S. It is used to transport information on a climbing elevator car-like lifter. However, there are arguments on its effectivity and uses because the government cannot afford to fail because of the estimated cost that reached ten billion dollars.

The article reports on the laser-based method of cleaning nanotubes. It notes that materials such as carbon nanotubes develop contaminants such as soot and graphite when synthesized. Purification is needed in order for the materials to be effective in their applications. Researchers at the National Institute of Standards and Technology (NIST) and the National Renewable Energy Laboratory (NREL) in the U.S. use excimer laser pulses to remove impurities.

Speciality compounder RTP Company, headquartered in Winona, MN, USA, has expanded its line of conductive compounds to include new CCX Conductive Masterbatches. The range is available in a number of different resin systems and can be formulated with four distinct additive technologies: stainless steel fibre, carbon nanotubes, carbon black and the company's PermaStat® inherently dissipative polymer technology. According to RTP, the masterbatches set 'a new standard for safe, productive and reliable solutions' for environments that require static dissipation or protection from electrostatic discharge (ESD). [ABSTRACT FROM AUTHOR]

Background: Commercial use of carbon nanotubes and nanofibers (CNT/F) in composites and electronics is increasing; however, little is known about health effects among workers. We conducted a cross-sectional study among 108 workers at 12 U.S. CNT/F facilities. We evaluated chest symptoms or respiratory allergies since starting work with CNT/F, lung function, resting blood pressure (BP), resting heart rate (RHR), and complete blood count (CBC) components. Methods: We conducted multi-day, full-shift sampling to measure background-corrected elemental carbon (EC) and CNT/F structure count concentrations, and collected induced sputum to measure CNT/F in the respiratory tract. We measured (nonspecific) fine and ultrafine particulate matter mass and count concentrations. Concurrently, we conducted physical examinations, BP measurement, and spirometry, and collected whole blood. We evaluated associations between exposures and health measures, adjusting for confounders related to lifestyle and other occupational exposures. Results: CNT/F air concentrations were generally low, while 18% of participants had evidence of CNT/F in sputum. Respiratory allergy development was positively associated with inhalable EC (p=0.040) and number of years worked with CNT/F (p=0.008). No exposures were associated with spirometry-based metrics or pulmonary symptoms, nor were CNT/F-specific metrics related to BP or most CBC components. Systolic BP was positively associated with fine particulate matter (p-values: 0.015-0.054). RHR was positively associated with EC, at both the respirable (p=0.0074) and inhalable (p=0.0026) size fractions. Hematocrit was positively associated with the log of CNT/F structure counts (p=0.043). Conclusions: Most health measures were not associated with CNT/F. The positive associations between CNT/F exposure and respiratory allergies, RHR, and hematocrit counts may not be causal and require examination in other studies. [ABSTRACT FROM AUTHOR]

The article discusses the study which aims to increase the mechanical properties and strength of the hydroxyapatite (HA) coating by a nanoreinforcement of the HA composite. The study used the coating on titanium synthesized by plasma spraying method, which was approved by the U.S. Food and Drug Administration (FDA) for HA coating orthopaedic implants. Results show that the tissues around the implants were normal with no carbon nanotube (CNT) migration.

Nanotechnology is stuck in a rut, and still needs to get to grasp on the fundamentals. But leading US research organisations have set up the Nano2 study, and are pinning hopes on electronics being the driver for the next decade of innovations according to the author. [ABSTRACT FROM AUTHOR]

Researchers at Rensselaer Polytechnic Institute in the USA have recently published three new studies that suggest that graphene should be the nanomaterial of choice to strengthen composite materials used in applications such as wind turbines and aircraft wings. [Copyright &y& Elsevier]

The article discusses the use of carbon nanotubes as single-molecular sensors, which has been illustrated by the detection of single strands of DNA molecules. The electronic properties of carbon nanotubes make them ideal components for nanocircuits. The team of Stuart Lindsay and Colin Nuckolls of the Arizona State-Columbia-Oak Ridge have used single-walled nanotubes to examine single-stranded DNA molecules. They found that low ionic conduction was a characteristic of semiconducting nanotubes.

CNano Technology Ltd (www.cnanotechnology.com) has received regulatory approval from the US Environmental Protection Agency (EPA) to sell multi-wall carbon nanotubes (MWCNTs) through its subsidiary in the USA. This approval places CNano on the shortlist of manufacturers approved to supply these products in the USA under the strict nanotechnology regulations of the EPA. The approval results from the pre-manufacturing notice filed by CNano for the MWCNTs produced at its new 500 tons/year facility in Beijing, China [ADPO, September 2009]. [Copyright &y& Elsevier]

Bayer MaterialScience has begun work on the construction of a 200 t/year facility for the production of multi-wall carbon nanotubes (CNTs) at its Leverkusen site in Germany. The catalytic chemical vapour deposition (CCVD) plant, claimed to be the largest of its type worldwide, will consist of a fluid bed reactor, catalyst dosing and product filling equipment. [Copyright &y& Elsevier]

This section offers news briefs on nanotechnology research. U.S. researchers have managed to isolate and crystallize a gold-thiolate cluster, which allowed them to determine the X-ray structure of gold nanoparticles. Scientists in Australia have studied the behavior of zinc oxide nanoparticles in freshwater systems to better understand their potential toxicity. Researchers in Spain have used a carbon nanotube to build a transistor that detects single electrons.

This section offers news briefs on nanotechnology research. U.S. researchers have shown that giant fullerenes formed inside multiwalled carbon nanotubes evaporate to produce smaller structures with their carbon shells remaining intact. Scientists from South Korea report a general approach for the self assembly of bioactive nanostructures with good control over their size and shape. Researchers in the U.S. have developed a strategy to explore how the geometry of a nanocontainer affects the dynamics of biopolymers.

The article reports on a method for measuring the interaction between carbon nanotubes and chemical functional groups on the atomic scale developed by researchers at the Lawrence Livermore National Laboratory of U.S. Department of Energy. In measuring a specific interaction for a single functional group with carbon nanotubes, researchers used chemical force microscopy. The understanding of such interaction is useful for the engineering future generation of sensors and nanodevices.

An interview with AIST Research Center for Advanced Carbon Materials researcher Sumio Iijima is presented. He talks about the events leading to his discovery of carbon nanotubes. He offers information on the main applications of nanotubes and their safety. Iijima offers a comparison of his experiences working in the U.S. and Japan and in universities and industry.