Pub Date : 2013-06-26DOI: 10.1142/S0219607712500073
Emily Wischow, L. Bryan, G. Bodner
Nanoscale science is a rapidly-developing, multidisciplinary field of science and research that combines engineering, chemistry, physics, biology, and information technology pushes and the boundary between the science and the technology required to conduct it. Nanoscale science involves investigating and working with matter on the scale of 1–100 microns and has broad societal implications for new technologies. It is estimated that the worldwide workforce necessary to support the field of nanoscale science and nanotechnology will be close to 2 million by 2015 (National Nanotechnology Initiative, 2005). With such rapid developments in nanoscale science and technology, it is becoming more incumbent upon K-12 science teachers to provide the learning experiences necessary for students to understand the principles that govern behavior at the nanoscale and develop the skills needed to apply these concepts to improve everyday life. While onlya limited amount of nanoscale curricular materials are available for K-12 and undergraduate education many important unanswered questions exist, including: How do science teachers learn to teach nanoscale science?
{"title":"SECONDARY SCIENCE TEACHERS' DEVELOPMENT OF PEDAGOGICAL CONTENT KNOWLEDGE AS RESULT OF INTEGRATING NANOSCIENCE CONTENT IN THEIR CURRICULUM","authors":"Emily Wischow, L. Bryan, G. Bodner","doi":"10.1142/S0219607712500073","DOIUrl":"https://doi.org/10.1142/S0219607712500073","url":null,"abstract":"Nanoscale science is a rapidly-developing, multidisciplinary field of science and research that combines engineering, chemistry, physics, biology, and information technology pushes and the boundary between the science and the technology required to conduct it. Nanoscale science involves investigating and working with matter on the scale of 1–100 microns and has broad societal implications for new technologies. It is estimated that the worldwide workforce necessary to support the field of nanoscale science and nanotechnology will be close to 2 million by 2015 (National Nanotechnology Initiative, 2005). With such rapid developments in nanoscale science and technology, it is becoming more incumbent upon K-12 science teachers to provide the learning experiences necessary for students to understand the principles that govern behavior at the nanoscale and develop the skills needed to apply these concepts to improve everyday life. While onlya limited amount of nanoscale curricular materials are available for K-12 and undergraduate education many important unanswered questions exist, including: How do science teachers learn to teach nanoscale science?","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"106 1","pages":"187-209"},"PeriodicalIF":0.0,"publicationDate":"2013-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87951934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-06-26DOI: 10.1142/S0219607712300056
J. Dillon
Policies designed to increase public engagement with biodiversity advocate increased education across a range of educational contexts. Evidence of the benefits of learning in natural environments (LINE) continues to be amassed. LINE affords direct benefits as diverse as educational, health and psychological and indirect benefits ranging from social to financial. Research into the value of LINE has failed to address the full range of benefits. Instead, there has been a narrow focus on easily measurable outcomes and a desire to seek answers to simplistic questions such as "does LINE raise standards more than learning in the classroom?" An attempt is made to outline the full range of benefits which are available to all school students. The outcomes include: benefits to individual participants (knowledge and understanding; skills; attitudes and behaviours; health and well-being; self-efficacy and self-worth); benefits to teachers, schools and the wider community, and benefits to the natural environment sector. Several barriers exist to the effective delivery of LINE. These barriers can be grouped into those that challenge the natural environment sector and those that challenge schools. The challenges facing the sector include a lack of a coordinated effective approach to working with schools at a local level. The challenges facing schools include those frequently mentioned such as the risk of accidents, cost and curriculum pressures. However, another set of challenges exists, at local, institutional and personal levels. These challenges include teachers' confidence, self-efficacy and their access to training in using natural environments close to the school and further afield.
{"title":"Barriers and Benefits to Learning in Natural Environments: Towards a Reconceptualisation of the Possibilities for Change","authors":"J. Dillon","doi":"10.1142/S0219607712300056","DOIUrl":"https://doi.org/10.1142/S0219607712300056","url":null,"abstract":"Policies designed to increase public engagement with biodiversity advocate increased education across a range of educational contexts. Evidence of the benefits of learning in natural environments (LINE) continues to be amassed. LINE affords direct benefits as diverse as educational, health and psychological and indirect benefits ranging from social to financial. Research into the value of LINE has failed to address the full range of benefits. Instead, there has been a narrow focus on easily measurable outcomes and a desire to seek answers to simplistic questions such as \"does LINE raise standards more than learning in the classroom?\" An attempt is made to outline the full range of benefits which are available to all school students. The outcomes include: benefits to individual participants (knowledge and understanding; skills; attitudes and behaviours; health and well-being; self-efficacy and self-worth); benefits to teachers, schools and the wider community, and benefits to the natural environment sector. Several barriers exist to the effective delivery of LINE. These barriers can be grouped into those that challenge the natural environment sector and those that challenge schools. The challenges facing the sector include a lack of a coordinated effective approach to working with schools at a local level. The challenges facing schools include those frequently mentioned such as the risk of accidents, cost and curriculum pressures. However, another set of challenges exists, at local, institutional and personal levels. These challenges include teachers' confidence, self-efficacy and their access to training in using natural environments close to the school and further afield.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"3 1","pages":"153-166"},"PeriodicalIF":0.0,"publicationDate":"2013-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75268674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-26DOI: 10.1142/S0219607712300044
M. M. Saw
Metal complexes have been used as medicinal compounds. Metals have advantageous features over organic compounds. Significant applications of metal complexes are in the field of nuclear medicine. Radiopharmaceuticals are drugs containing radioisotopes used for diagnostic and therapeutic purposes. The generalized targeting strategy for molecular imaging probe consists of three essential parts: (i) reporter unit or payload, (ii) carrier, and (iii) targeting system. Medicinal radiopharmaceutical chemistry pays special consideration to radioisotopes, as a reporter unit for diagnostic application or as a payload for therapeutic application. Targeting is achieved by a few approaches but the most common is the bifunctional chelator approach. While designing a radiopharmaceutical, a range of issues needs to be considered including properties of metal radioisotopes, bifunctional chelators, linkers, and targeting molecules. Designing radiopharmaceuticals requires consideration of two key words: "compounds of biological interest" and "fit for intended use." The ultimate goal is the development of new diagnostic methods and treatment. Diagnostic metal radiopharmaceuticals are used for SPECT and PET applications. Technetium chemistry constitutes a major portion of SPECT and gallium chemistry constitutes a major portion of PET. Therapeutic radiopharmaceuticals can be constructed by using alpha-, beta minus-, or Auger electron-emitting radiometals. Special uses of medicinal radiopharmaceuticals include internal radiation therapy, brachytherapy, immunoPET, radioimmunotherapy, and peptide receptor radionuclide imaging and therapy.
{"title":"MEDICINAL RADIOPHARMACEUTICAL CHEMISTRY OF METAL RADIOPHARMACEUTICALS","authors":"M. M. Saw","doi":"10.1142/S0219607712300044","DOIUrl":"https://doi.org/10.1142/S0219607712300044","url":null,"abstract":"Metal complexes have been used as medicinal compounds. Metals have advantageous features over organic compounds. Significant applications of metal complexes are in the field of nuclear medicine. Radiopharmaceuticals are drugs containing radioisotopes used for diagnostic and therapeutic purposes. The generalized targeting strategy for molecular imaging probe consists of three essential parts: (i) reporter unit or payload, (ii) carrier, and (iii) targeting system. Medicinal radiopharmaceutical chemistry pays special consideration to radioisotopes, as a reporter unit for diagnostic application or as a payload for therapeutic application. Targeting is achieved by a few approaches but the most common is the bifunctional chelator approach. While designing a radiopharmaceutical, a range of issues needs to be considered including properties of metal radioisotopes, bifunctional chelators, linkers, and targeting molecules. Designing radiopharmaceuticals requires consideration of two key words: \"compounds of biological interest\" and \"fit for intended use.\" The ultimate goal is the development of new diagnostic methods and treatment. Diagnostic metal radiopharmaceuticals are used for SPECT and PET applications. Technetium chemistry constitutes a major portion of SPECT and gallium chemistry constitutes a major portion of PET. Therapeutic radiopharmaceuticals can be constructed by using alpha-, beta minus-, or Auger electron-emitting radiometals. Special uses of medicinal radiopharmaceuticals include internal radiation therapy, brachytherapy, immunoPET, radioimmunotherapy, and peptide receptor radionuclide imaging and therapy.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"31 1","pages":"11-81"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82586404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-26DOI: 10.1142/S0219607712300020
Daniel Yuan Qiang Wong, W. Ang
The serendipitous discovery of the antitumor properties of cisplatin by Barnett Rosenberg some forty years ago brought about a paradigm shift in the field of medicinal chemistry and challenged conventional thinking regarding the role of potentially toxic heavy metals in drugs. Platinum(II)-based anticancer drugs have since become some of the most effective and widely-used drugs in a clinician's arsenal and have saved countless lives. However, they are limited by high toxicity, severe side-effects and the incidence of drug resistance. In recent years, attention has shifted to stable platinum(IV) complexes as anticancer prodrugs. By exploiting the unique chemical and structural attributes of their scaffolds, these platinum(IV) prodrugs offer new strategies of targeting and killing cancer cells. This review summarizes the development of anticancer platinum(IV) prodrugs to date and some of the exciting strategies that utilise the platinum(IV) construct as targeted chemotherapeutic agents against cancer.
{"title":"DEVELOPMENT OF PLATINUM(IV) COMPLEXES AS ANTICANCER PRODRUGS: THE STORY SO FAR","authors":"Daniel Yuan Qiang Wong, W. Ang","doi":"10.1142/S0219607712300020","DOIUrl":"https://doi.org/10.1142/S0219607712300020","url":null,"abstract":"The serendipitous discovery of the antitumor properties of cisplatin by Barnett Rosenberg some forty years ago brought about a paradigm shift in the field of medicinal chemistry and challenged conventional thinking regarding the role of potentially toxic heavy metals in drugs. Platinum(II)-based anticancer drugs have since become some of the most effective and widely-used drugs in a clinician's arsenal and have saved countless lives. However, they are limited by high toxicity, severe side-effects and the incidence of drug resistance. In recent years, attention has shifted to stable platinum(IV) complexes as anticancer prodrugs. By exploiting the unique chemical and structural attributes of their scaffolds, these platinum(IV) prodrugs offer new strategies of targeting and killing cancer cells. This review summarizes the development of anticancer platinum(IV) prodrugs to date and some of the exciting strategies that utilise the platinum(IV) construct as targeted chemotherapeutic agents against cancer.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"47 1","pages":"121-134"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82532727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-26DOI: 10.1142/S0219607712500048
T. Ng
It is known that one strength of MRI is its excellent soft tissue discrimination. It naturally provides sufficient contrast between the structural differences of normal and pathological tissues, their spatial extent and progression. However, to further extend its applications and enhance even more contrast for clinical studies, various Gadolinium (Gd)-based contrast agents have been developed for different organs (brain strokes, cancer, cardio-MRI, etc). These Gd-based contrast agents are paramagnetic compounds that have strong T1-effect for enhancing the contrast between tissue types. Gd-contrast can also enhance magnetic resonance angiography (CE-MRA) for studying stenosis and for measuring perfusion, vascular susceptibility, interstitial space, etc. Another class of contrast agents makes use of ferrite iron oxide nanoparticles (including Superparamagnetic Ion Oxide (SPIO) and Ultrasmall Superparamagnetic Iron Oxide (USPIO)). These nanoparticles have superior magnetic susceptibility effect and produce a drop in signal, namely in -weighted images, useful for the determination of lymph nodes metastases, angiogenesis and arteriosclerosis plaques.
{"title":"GADOLINIUM(Gd)-BASED AND ION OXIDE NANOPARTICLE CONTRAST AGENTS FOR PRE-CLINICAL AND CLINICAL MAGNETIC RESONANCE IMAGING (MRI) RESEARCH","authors":"T. Ng","doi":"10.1142/S0219607712500048","DOIUrl":"https://doi.org/10.1142/S0219607712500048","url":null,"abstract":"It is known that one strength of MRI is its excellent soft tissue discrimination. It naturally provides sufficient contrast between the structural differences of normal and pathological tissues, their spatial extent and progression. However, to further extend its applications and enhance even more contrast for clinical studies, various Gadolinium (Gd)-based contrast agents have been developed for different organs (brain strokes, cancer, cardio-MRI, etc). These Gd-based contrast agents are paramagnetic compounds that have strong T1-effect for enhancing the contrast between tissue types. Gd-contrast can also enhance magnetic resonance angiography (CE-MRA) for studying stenosis and for measuring perfusion, vascular susceptibility, interstitial space, etc. Another class of contrast agents makes use of ferrite iron oxide nanoparticles (including Superparamagnetic Ion Oxide (SPIO) and Ultrasmall Superparamagnetic Iron Oxide (USPIO)). These nanoparticles have superior magnetic susceptibility effect and produce a drop in signal, namely in -weighted images, useful for the determination of lymph nodes metastases, angiogenesis and arteriosclerosis plaques.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"190 1","pages":"103-119"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74450673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-26DOI: 10.1142/S0219607712300019
R. Alberto
Technetium and Rhenium are the two lower elements in the manganese triad. Whereas rhenium is known as an important part of high resistance alloys, technetium is mostly known as a cumbersome product of nuclear fission. It is less known that its metastable isotope 99mTc is of utmost importance in nuclear medicine diagnosis. The technical application of elemental rhenium is currently complemented by investigations of its isotope 188Re, which could play a central role in the future for internal, targeted radiotherapy. This article will briefly describe the basic principles behind diagnostic methods with radionuclides for molecular imaging, review the 99mTc-based radiopharmaceuticals currently in clinical routine and focus on the chemical challenges and current developments towards improved, radiolabeled compounds for diagnosis and therapy in nuclear medicine.
{"title":"Application of Technetium and Rhenium in Nuclear Medicine","authors":"R. Alberto","doi":"10.1142/S0219607712300019","DOIUrl":"https://doi.org/10.1142/S0219607712300019","url":null,"abstract":"Technetium and Rhenium are the two lower elements in the manganese triad. Whereas rhenium is known as an important part of high resistance alloys, technetium is mostly known as a cumbersome product of nuclear fission. It is less known that its metastable isotope 99mTc is of utmost importance in nuclear medicine diagnosis. The technical application of elemental rhenium is currently complemented by investigations of its isotope 188Re, which could play a central role in the future for internal, targeted radiotherapy. This article will briefly describe the basic principles behind diagnostic methods with radionuclides for molecular imaging, review the 99mTc-based radiopharmaceuticals currently in clinical routine and focus on the chemical challenges and current developments towards improved, radiolabeled compounds for diagnosis and therapy in nuclear medicine.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"20 1","pages":"83-101"},"PeriodicalIF":0.0,"publicationDate":"2012-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84428244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-11-20DOI: 10.1142/S0219607711000717
S. Punireddy, Sundaramurthy Jayaraman, R. Gupta, S. Yeong, F. Zhang, Z. Jia, M. Srinivasan
A wide range of new materials for many applications can be formed by controlling the composition and order of constituents at the molecular level. For systems thus engineered, ensuring chemical, thermal and mechanical robustness is a major challenge. Consequently, polyimides and other imide-containing materials are attractive as matrices for functional materials. We investigate the construction of functional nanostructures in organic/polymeric matrices with clearly demonstrated chemical, thermal and mechanical stability. Surface functionalization, layer-by-layer (LBL) assembly in various media (including supercritical), incorporation of functional moieties, molecular orientation, and interfacial reactions are areas of interest. We demonstrate the robustness of ultrathin film structures containing polyimides and oligoimides formed by LBL molecular assembly with inter-layer covalent links. Covalent bonding between the layers provides strength, while utilizing a supercritical medium for the processing, results in the deployment of a solvent-free environment and avoids problems related to residual solvent, thereby improving film quality when compared to conventional films.
{"title":"NANOFABRICATION BY COVALENT MOLECULAR ASSEMBLY: A PATHWAY TO ROBUST STRUCTURES","authors":"S. Punireddy, Sundaramurthy Jayaraman, R. Gupta, S. Yeong, F. Zhang, Z. Jia, M. Srinivasan","doi":"10.1142/S0219607711000717","DOIUrl":"https://doi.org/10.1142/S0219607711000717","url":null,"abstract":"A wide range of new materials for many applications can be formed by controlling the composition and order of constituents at the molecular level. For systems thus engineered, ensuring chemical, thermal and mechanical robustness is a major challenge. Consequently, polyimides and other imide-containing materials are attractive as matrices for functional materials. We investigate the construction of functional nanostructures in organic/polymeric matrices with clearly demonstrated chemical, thermal and mechanical stability. Surface functionalization, layer-by-layer (LBL) assembly in various media (including supercritical), incorporation of functional moieties, molecular orientation, and interfacial reactions are areas of interest. We demonstrate the robustness of ultrathin film structures containing polyimides and oligoimides formed by LBL molecular assembly with inter-layer covalent links. Covalent bonding between the layers provides strength, while utilizing a supercritical medium for the processing, results in the deployment of a solvent-free environment and avoids problems related to residual solvent, thereby improving film quality when compared to conventional films.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"12 1","pages":"31-42"},"PeriodicalIF":0.0,"publicationDate":"2011-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81129185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-11-20DOI: 10.1142/S0219607711000729
S. Adams
Batteries are in most people's mind devices to power small-scale mobile applications ranging from children's toys, cell phones and cameras to tablet computers and laptops, but we hardly think about the considerably wider range of electrochemical energy storage (EES) down to microbatteries that deliver milliwatts for smart-card devices or up via 10 30 kWh batteries powering electric drive vehicles to utility-scale stationary EES system that need to store tens to hundreds of MWh to locally balance demand in the power grid with energy supply from renewable sources. Currently it is the two latter applications, electromobility in battery electric vehicles (BEV) or plug-in hybrid electric vehicles (PHEV) and load leveling of power grids based on renewable sources, that appear to pose the key challenges to materials scientists and drive advancement of electrochemical energy storage technology. Due to their high energy density, rechargeable lithium ion batteries (LIBs) based on layered electrode materials [LiCoO2 as cathode (positive electrode), graphite as anode (negative electrode)] and organic liquid or polymeric gel electrolytes are the present-day choice as EES for small-scale portable appliances. LIBs possess high working voltage ( 3.6V) and thereby high energy-density compared to earlier rechargeable battery technologies such as Ni-Cd, NiMH and lead acid batteries. Global production (mostly in Asia) grows by 30% per year so that LIBs steadily increase their share of the also expanding battery market, that is estimated to reach 86 billion US$ in 2016. Road transportation constitutes a signi cant portion of energy consumption in Singapore as in most industrialized countries, 5 and the fast rise of vehicle population in developing countries is one of the main drivers of petroleum price increases. Provided that energy storage systems are technically and economically viable, high e±ciency electric vehicles (EV) have a number of advantages over current internal combustion engine cars:
{"title":"KEY MATERIALS CHALLENGES FOR ELECTROCHEMICAL ENERGY STORAGE SYSTEMS","authors":"S. Adams","doi":"10.1142/S0219607711000729","DOIUrl":"https://doi.org/10.1142/S0219607711000729","url":null,"abstract":"Batteries are in most people's mind devices to power small-scale mobile applications ranging from children's toys, cell phones and cameras to tablet computers and laptops, but we hardly think about the considerably wider range of electrochemical energy storage (EES) down to microbatteries that deliver milliwatts for smart-card devices or up via 10 30 kWh batteries powering electric drive vehicles to utility-scale stationary EES system that need to store tens to hundreds of MWh to locally balance demand in the power grid with energy supply from renewable sources. Currently it is the two latter applications, electromobility in battery electric vehicles (BEV) or plug-in hybrid electric vehicles (PHEV) and load leveling of power grids based on renewable sources, that appear to pose the key challenges to materials scientists and drive advancement of electrochemical energy storage technology. Due to their high energy density, rechargeable lithium ion batteries (LIBs) based on layered electrode materials [LiCoO2 as cathode (positive electrode), graphite as anode (negative electrode)] and organic liquid or polymeric gel electrolytes are the present-day choice as EES for small-scale portable appliances. LIBs possess high working voltage ( 3.6V) and thereby high energy-density compared to earlier rechargeable battery technologies such as Ni-Cd, NiMH and lead acid batteries. Global production (mostly in Asia) grows by 30% per year so that LIBs steadily increase their share of the also expanding battery market, that is estimated to reach 86 billion US$ in 2016. Road transportation constitutes a signi cant portion of energy consumption in Singapore as in most industrialized countries, 5 and the fast rise of vehicle population in developing countries is one of the main drivers of petroleum price increases. Provided that energy storage systems are technically and economically viable, high e±ciency electric vehicles (EV) have a number of advantages over current internal combustion engine cars:","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"101 1","pages":"11-24"},"PeriodicalIF":0.0,"publicationDate":"2011-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75455476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-11-20DOI: 10.1142/S0219607711000699
E. Leong, Hong Liu, Y. Liu, J. Teng
Metamaterials are specially designed periodic structures (a ) that give rise to extraordinary optical properties that no natural materials can possess. It can have extremely large refractive index or a negative refractive index over a frequency band. The refractive index, n, determines how light travels in a medium and is related to the permittivity, ", and permeability, , by the relation n 1⁄4 ð" Þ1=2. It was ̄rst pointed out by Veselago that if " < 0 and < 0, then n becomes negative. Nevertheless, there are no natural materials that possess negative permeability, though metals possess negative permittivity at subplasma frequency. However it was Pendry's suggestion that negative refraction would make a perfect lens that drawn worldwide interests in this ̄eld. 5 Besides subwavelength di®raction limited imaging, metamaterials have also found applications in areas such as wideband directive antennas, band-stop ̄lters, radar absorbers, broadband phase shifters, cloaking and far̄eld optical microscopy. These can be achieved by engineering the propagation of light in the structure. This list of potential applications is non-exhaustive asmore concentrated e®orts are currently ongoing all over the world to design new structures and improve on old ones. The beauty of using metamaterial structures in devices is that the design can be made much smaller with improved performances, or at least comparable performances with conventionally established techniques. Ernest Abbe (184
{"title":"OPTICAL METAMATERIALS AND SUPER-RESOLUTION IMAGING","authors":"E. Leong, Hong Liu, Y. Liu, J. Teng","doi":"10.1142/S0219607711000699","DOIUrl":"https://doi.org/10.1142/S0219607711000699","url":null,"abstract":"Metamaterials are specially designed periodic structures (a ) that give rise to extraordinary optical properties that no natural materials can possess. It can have extremely large refractive index or a negative refractive index over a frequency band. The refractive index, n, determines how light travels in a medium and is related to the permittivity, \", and permeability, , by the relation n 1⁄4 ð\" Þ1=2. It was ̄rst pointed out by Veselago that if \" < 0 and < 0, then n becomes negative. Nevertheless, there are no natural materials that possess negative permeability, though metals possess negative permittivity at subplasma frequency. However it was Pendry's suggestion that negative refraction would make a perfect lens that drawn worldwide interests in this ̄eld. 5 Besides subwavelength di®raction limited imaging, metamaterials have also found applications in areas such as wideband directive antennas, band-stop ̄lters, radar absorbers, broadband phase shifters, cloaking and far̄eld optical microscopy. These can be achieved by engineering the propagation of light in the structure. This list of potential applications is non-exhaustive asmore concentrated e®orts are currently ongoing all over the world to design new structures and improve on old ones. The beauty of using metamaterial structures in devices is that the design can be made much smaller with improved performances, or at least comparable performances with conventionally established techniques. Ernest Abbe (184","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"6 1","pages":"43-63"},"PeriodicalIF":0.0,"publicationDate":"2011-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83718769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-11-20DOI: 10.1142/S0219607711000705
T. Tahmasebi, S. Piramanayagam
Data storage is one area of technology where nanotechnology has been used even before the term nanotechnology became very popular. The magnetic recording media — the disk that stores information in hard disk drives — used nanotechnology in the late 1990s, in the form of grains which are 15 nm or less in diameter (the grains in current technology are about 8 nm in diameter). The reading sensors of hard disk also make use of thin nanostructures in several dimensions to read information from the recording media. This paper introduces the technology behind the magnetic random access memory and related topics, which form the core of the symposium L of ICMAT 2011, which is titled "Memory, Nanomagnetics, Materials and Devices".
{"title":"NANOSCIENCE AND NANOTECHNOLOGY FOR MEMORY AND DATA STORAGE","authors":"T. Tahmasebi, S. Piramanayagam","doi":"10.1142/S0219607711000705","DOIUrl":"https://doi.org/10.1142/S0219607711000705","url":null,"abstract":"Data storage is one area of technology where nanotechnology has been used even before the term nanotechnology became very popular. The magnetic recording media — the disk that stores information in hard disk drives — used nanotechnology in the late 1990s, in the form of grains which are 15 nm or less in diameter (the grains in current technology are about 8 nm in diameter). The reading sensors of hard disk also make use of thin nanostructures in several dimensions to read information from the recording media. This paper introduces the technology behind the magnetic random access memory and related topics, which form the core of the symposium L of ICMAT 2011, which is titled \"Memory, Nanomagnetics, Materials and Devices\".","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"10 1","pages":"25-30"},"PeriodicalIF":0.0,"publicationDate":"2011-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76396296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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