Nanotechnology Conference Research Articles

With Functionalization, Nanodiamonds May Increase Durability of PDC Cutters

This article, written by Editorial Manager Adam Wilson, contains highlights of paper SPE 157039, ’The Trick Is the Surface - Functionalized Nanodiamond PDC Technology,’ by Soma Chakraborty, SPE, Gaurav Agrawal, SPE, Anthony DiGiovanni, SPE, and Dan Scott, SPE, Baker Hughes, prepared for the 2012 SPE International Oilfield Nanotechnology Conference and Exhibition, Noordwijk, The Netherlands, 12-14 June. The paper has not been peer reviewed. With downhole conditions shifting toward more challenging conditions, nanoparticles have been explored for more demanding applications. As a result of their inherent extremely high surface energy, these very small particles tend to attract each other or exist as clusters. Thus, nanoparticles can exist as micrometer-sized clusters, exhibiting overall micrometer features instead of nanometer characteristics. To derive the true benefits of a nanoparticle, it is crucial to exfoliate and derivatize the surface so the system is truly “nano.” Derivatization, or “functionalization,” further stabilizes the nanoparticles in chemical matrices. In this context, nanodiamonds have been functionalized for polycrystalline diamond applications such as polycrystalline diamond compact (PDC) cutters for drill bits. Introduction Nanodiamond is an interesting candidate for increasing the durability of PDC cutters as well as their abrasion resistance. As one possible means of increasing overall PDC diamond density and lowering the amount of metallic binder, nanodiamonds could lower the localized microstructural stress as their coefficient of thermal expansion is matched to that of the micrometer diamond. Diamond-to-diamond bonding is likewise straight-forward, compared with a nondiamond nano-sized second phase. Several varieties of nanodiamond are commercially available. One variety is obtained from milling synthetic micrometer diamond, which results in large size distributions. Another variety is the shock-wave nanodiamond, which is composed of sintered granules, with granule size dependent on the starting graphene. The most extensively used variety is the detonation nanodiamond, which has a very narrow size distribution, with average crystallite size of 5–7 nm. The surface functionality and reactivity are dependent on the generation method and purification techniques. Similar to most nanoparticles, nanodiamond has very high surface energy because of its extremely small size. To minimize the surface energy, it aggregates into micrometer- or submicrometer-sized hard clusters. These aggregates are very difficult to break or control during bulk processing. A PDC synthesized from aggregated nanodiamond would have inhomogeneous diamond distribution, which would ultimately lead to inferior performance and poor reliability with respect to the baseline feed. To overcome the problem, nanodiamond particles are functionalized or surface derivatized to covalently attach organic moieties onto their surface. The surface functional groups get covalently bonded onto the nanodiamond surface on the basis of the synergy of the surface active sites and associated reactivity of the bonding fragment.

Nanoparticle Use in Drilling Fluids Can Effectively Reduce Permeability in Shale

This article, written by Editorial Manager Adam Wilson, contains highlights of paper SPE 157031, ’Application of Nanotechnology in Drilling Fluids,’ by Katherine Price Hoelscher, SPE, Guido De Stefano, SPE, Meghan Riley, SPE, and Steve Young, SPE, M-I SWACO, prepared for the 2012 SPE International Oilfield Nanotechnology Conference and Exhibition, Noordwijk, The Netherlands, 12-14 June. The paper has not been peer reviewed. The potential to apply water-based drilling fluids confidently in unconventional shale formations has been studied using engineered nanoparticles to minimize shale permeability by physically plugging the nanometer-sized pores. Nanoparticle technology and testing protocols were developed using the Marcellus and the Mancos as shale candidates. Nanoparticles in this study are specifically designed to plug the nanometer-sized shale pores physically, thereby reducing pressure transmission in the shale. Introduction Silica nanoparticles are commercially available and can be engineered to meet all specifications needed for the purpose. The particle size can vary between 5 and 100 nm. The right sizes of nanoparticles can be selected, and, in combination with a correct fluid-loss package, the particles can minimize the fluid/rock interaction. Surface treatment on the nanosilica particle has been discovered to have a major influence on the final performance. An investigation into using nanoparticles as a drilling-fluid additive to enhance wellbore stability has been successful. The nanomaterial works by virtually shutting off water movement between the formation and wellbore. In shale formations with nanodarcy permeability, such as the Marcellus, the usual drilling-fluid method of relying on a filter cake to reduce fluid loss (or leakoff) cannot be used because a filter cake may not form because of the extremely low permeability of the shale. The solution for this problem is to engineer a nanoparticle that will be added to the drilling fluid to plug the pores of the shale and shut off water loss. Background The hurdle to maintaining wellbore stability in shale formations is to control the water interaction with the rock. The water enters the shale through pores, which vary in size from approximately 3 to 100 nm, inducing fractures and, thereby, reducing the stability of the wellbore. By effectively plugging the exposed pores of the rock and not allowing water to enter, wellbore stability is retained. One conventional bridging theory is referred to as the one-third rule of filtration (Abrahm’s theory), where the material used to plug a pore is required to be approximately one-third to one-seventh of the size of median pore opening. There are other theories with varying size requirements for the plugging material; however, none is perfect. An ideal plugging material also will accommodate the variability in pores within the formation.

Novel Nanoparticle-Based Drilling Fluid Reveals Improved Characteristics

This article, written by Editorial Manager Adam Wilson, contains highlights of paper SPE 156992, ’Novel Nanoparticle-Based Drilling Fluid With Improved Characteristics,’ by Mohammad F. Zakaria, Maen Husein, and Geir Hareland, SPE, University of Calgary, prepared for the 2012 SPE International Oilfield Nanotechnology Conference and Exhibition, Noordwijk, The Netherlands, 12-14 June. The paper has not been peer reviewed. A new class of nanoparticle lost-circulation material (LCM) has been developed. Two different approaches of nanoparticle formation and addition to oil-based drilling fluid have been tested. All nanoparticles were prepared in house, either within the oil-based drilling fluid (in situ) or within an aqueous phase (ex situ), with the latter being eventually blended with the drilling fluid. Under a low-pressure/low-temperature (LP/LT) American Petroleum Institute standard test, more than 70% reduction in fluid loss was achieved in the presence of nanoparticles, compared with only 9% reduction in the presence of typical LCMs. Introduction LCMs with diameters in the range of 0.1–100m may play an important role when the cause of fluid loss occurs in 0.1-Μm to 1-mm porous formation. In practice, however, the size of pore openings in shales that may cause fluid loss varies in the range of 10 nm–0.1 m, where nanoparticles as LCM could fulfill the specific requirements by virtue of their size domain, hydrodynamic properties, and interaction potential with the formation. Nanoparticles are defined as particulate dispersions or solid particles with a size in the range of 1–100 nm. These particles are smaller than microparticles, have a high surface/volume ratio, and may provide superior fluid properties at low concentrations of the additives. The main application of nanoparticles would be to control the spurt and fluid loss into the formation and, hence, control formation damage. The presence of nanoparticles can lead to better sealing at an earlier stage of filter-cake formation and, subsequently, a thinner impermeable mudcake. Because of their high surface/volume ratio, the particles in the mudcake matrix can be removed easily by traditional cleaning systems during completion. Thus, the nanoparticles can be used as rheology modifiers, fluid-loss additives, and shale inhibitors at low concentrations without the fear of particles lingering in the drilled well.

Trends in Nanotechnology 2008

The 2008 Trends in NanoTechnology conference was recently held in Oviedo, Spain. An overview of the conference highlights and speakers is presented.

Editorial: phys. stat. sol. (RRL) 4/2007

Dear authors and readers, The present issue of pss – Rapid Research Letters sheds light on recent developments and future perspectives of nanoscience, an area which is now central to solid state physics, materials research, and – perhaps even more important – collaborations across disciplines. This is outlined in an essay by Antonio Correia and colleagues [1] who annually organize the successful Trends in Nanotechnology (TNT) conference series. Several closely related contributions follow, mainly focusing on preparation, various properties and applications of carbon nanotubes. We are also glad to report that the Letter on a new blue-violet nonpolar nitride LED published in April [2] has been featured as cover story in the June issue of Compound Semiconductor magazine. Consequently, the paper has quickly headed towards the top of our download statistics (see below). Now the UCSB/Mitsubishi team reports a further milestone with significantly enhanced parameters also for a green light emitter grown on semipolar substrate [3]. We continue to be very fast in editing, peer-review, and production of the journal (see updated graphics on p. A74). More details on how this is achieved will be given in one of the next issues of pss-RRL.

Formation of atomic-sized contacts controlled by electrochemical methods

The present special issue of physica status solidi (a) contains contributions from the TNT2006 – Trends in Nanotechnology Conference, held in Grenoble, France, 4–8 September 2006. Editor's Choice is the article by Reyes Calvo et al. [1], which reports on the possibilities of using electrochemical methods to form atomic-sized contacts. In particular, the authors analyze previous attempts and propose improvements on several methods, in order to increase the control and the ease of preparation of the nanocontacts. The cover picture shows the electrochemical cell (1 cm in diameter) used for the experiments (left) with a schematic of the electronic circuit used. An artistic view of the atomic contact is depicted at the top. The lower right panel shows the last stages of the evolution of the conductance of a gold wire while being electrochemically etched. The last plateau of conductance corresponds to a one-atom contact. The upper right panel shows the voltamogram of the wire prior to etching. This work was done mainly at the Low Temperatures & Nanotechnology Laboratory of the University of Alicante (Spain), lead by Dr. Carlos Untiedt. He is a “Ramon y Cajal” Researcher whose main research interest is the electronic transport in nanostructures, and in particular in atomic-sized contacts. The issue also contains an Original Paper on scientific policy entitled “Nanotechnology applications: a driving force for R&D investment” [2], and a Feature Article presenting a report on the synthesis of luminescent silicon nanostructures by means of laser ablation techniques by Riabinia et al. [3]. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Thousands gather in Japan for massive nanotechnology event

Why do hundreds of companies and tens of thousands of people attend a nanotechnology conference in Tokyo every year? Adarsh Sandhu finds out.

Ethical and social issues in nanobiotechnologies

Nanobiotechnologies represent a rapidly growing field of interest. Several European conferences during the past year have highlighted the wide‐ranging potential of applying techniques at the molecular and atomic levels to understand and transform biosystems, and of using biological principles and materials to create new devices at the nanoscale. This convergence of disciplines holds great promise in medicine for improved diagnostics, less invasive monitoring devices and more targeted therapies, and also has potential for agricultural and environmental applications. However, relatively little has been written about the ethical and social implications of this emerging research area. This article seeks to examine some of these questions, and is based on a report produced by the ethical, legal and social advisory (ELSA) board of the Nano2Life European Network of Excellence in Nanobiotechnology (Bruce, 2006). Nano2Life is funded by the European Commission (EC) under the Sixth Framework Programme. It brings together European research groups from 12 countries to collaborate in specific multidisciplinary projects, which combine the life sciences with microtechnologies and nanotechnologies, materials science, physics and chemistry. The aim is to develop new research tools and applications for medical diagnosis and therapy, and for monitoring food safety and environmental health. Seeking to learn from the major controversy in Europe over genetically modified (GM) foods, Nano2Life established—as an integral part of the network—an advisory board to evaluate possible ethical, legal and social implications. Its role is to advise on particular research projects, to educate participating scientists, and to produce a broad overview of the ethical and social issues (Bruce, 2006), which are summarized in this article. The reflections presented here are insights from board members and some participating scientists, and draw on an initial literature survey (Jomann, 2006). A main aim is to make researchers in both academia and industry aware of the broad ethical …

The fabrication and characterisation of metallic nanotransistors

Enormous research studies and funding have been invested into the field of transistor miniaturisation for the last five decades. For the smallest possible MOS transistor, a channel conductance close to that of a metal has been suggested [S.V. Rotkin, K. Hess, Principles of metallic field effect transistor, in: Technical Proceedings of the 2004 NSTI Nanotechnology Conference and Trade Show, vol. 2, 2004, pp. 37–40.]. Metallic nanotransistors are promising candidates that might serve as an alternative solution for overcoming the shrinking limit of conventional MOS structures. This type of transistor operates similarly to depletion type MOSFET by governing the flow of electrons through a narrow channel made from metallic nanowire. In the fabrication of metallic nanotransistors, an electron beam lithography process has been developed to fabricate structures at the sub 30 nm scale using silver nanowires on Si 3N 4 substrate. The one-dimensional structure and the use of single material for the construction of the metallic transistors also allow the use of advanced nanoimprint technology for rapid and economic fabrication. This paper details the design, fabrication and characterisation techniques for two structures of all metal nanotransistors.

Elements for surface microfluidics in diamond

Surface microfluidic elements are an essential part of lab-on-a-chip systems to perform complex chemical and biochemical synthesis as well as analyical tasks. These systems typically consist of channels, mixers and reaction chambers but also of actuators like pumps, heaters, etc., and sensors, measuring temperature, flow, impedance, pH, etc. To integrate these different functionalities, it is usually necessary to utilize different material systems [Eur. J. Pharm. Sci., 20(2) (2003) 149–171; Adv. Drug Delivery Rev., 55(3) (2003) 349–377]. Due to the unique properties of diamond, e.g. chemical inertness, UV transparency, high thermal conductivity and its semiconducting property, diamond can be universally used as base material for both passive and active elements. In previous work, the realization of temperature sensors, UV sensors and experimental ion sensitive FETs [Diamond Relat. Mater. 12 (2003) 554–559] has already been demonstrated. Various actuation principles like electrostatic [Diamond Relat. Mater. 12 (2003) 418–421], bubble-jet [Diamond Relat. Mater. 10 (2001) 722–730] and bi-metal actuators [Technical Proceedings of the 2003 Nanotechnology Conference, San Francisco, USA, February 23–27, (2003) pp. 380–383] have also been employed. This paper presents a new approach to the fabrication of all-diamond surface channels and chambers to link the different elements together and to provide a covered fluidic pathway. This needs high aspect ratio geometries and was obtained by modifying the common dielectric sacrificial layer technology used for MEMS [J.W. Gardner, Microsensors-Principles and Applications, John Wiley and Sons, Chichester, UK, 1994, p. 52ff], that is replacing the silicon dioxide by electroplated metal. Using an electroplating process, high thicknesses can be obtained. The sacrificial metal layer is then overgrown with diamond. As a first example, an integrated micro-membrane pump with thermal actuation is discussed.

Elements for surface microfluidics in diamond

Surface microfluidic elements are an essential part of lab-on-a-chip systems to perform complex chemical and biochemical synthesis as well as analyical tasks. These systems typically consist of channels, mixers and reaction chambers but also of actuators like pumps, heaters, etc., and sensors, measuring temperature, flow, impedance, pH, etc. To integrate these different functionalities, it is usually necessary to utilize different material systems [Eur. J. Pharm. Sci., 20(2) (2003) 149–171; Adv. Drug Delivery Rev., 55(3) (2003) 349–377]. Due to the unique properties of diamond, e.g. chemical inertness, UV transparency, high thermal conductivity and its semiconducting property, diamond can be universally used as base material for both passive and active elements. In previous work, the realization of temperature sensors, UV sensors and experimental ion sensitive FETs [Diamond Relat. Mater. 12 (2003) 554–559] has already been demonstrated. Various actuation principles like electrostatic [Diamond Relat. Mater. 12 (2003) 418–421], bubble-jet [Diamond Relat. Mater. 10 (2001) 722–730] and bi-metal actuators [Technical Proceedings of the 2003 Nanotechnology Conference, San Francisco, USA, February 23–27, (2003) pp. 380–383] have also been employed. This paper presents a new approach to the fabrication of all-diamond surface channels and chambers to link the different elements together and to provide a covered fluidic pathway. This needs high aspect ratio geometries and was obtained by modifying the common dielectric sacrificial layer technology used for MEMS [J.W. Gardner, Microsensors-Principles and Applications, John Wiley and Sons, Chichester, UK, 1994, p. 52ff], that is replacing the silicon dioxide by electroplated metal. Using an electroplating process, high thicknesses can be obtained. The sacrificial metal layer is then overgrown with diamond. As a first example, an integrated micro-membrane pump with thermal actuation is discussed.

Miniaturised nucleic acid analysis

The application of micro total analysis systems has grown exponentially over the past few years, particularly diversifying in disciplines related to bioassays. The primary focus of this review is to detail recent new approaches to sample preparation, nucleic acid amplification and detection within microfluidic devices or at the microscale level. We also introduce some applications that have as yet to be explored in a miniaturised environment, but should benefit from improvements in analytical efficiency and functionality when transferred to planar-chip formats. The studies described in this review were published in commonly available journals as well as in the proceedings of three major conferences relevant to microfluidics (Micro Total Analysis Systems, Transducers and The Nanotechnology Conference and Trade Show). Although an emphasis has been placed on papers published since 2002, pertinent articles preceding this publication year have also been included.

Nanotechnology Conference – A UK Interdisciplinary Event

Nanotechnology Conference – A UK Interdisciplinary Event