Velocity reversal and the arrows of time

Agendanken experiment is proposed for distinguishing between two models accounting for the macroscopic arrow of time. The experiment involves the veloeity revesal of components of an isolated system, and the two models give contrasting predictions as to its behavior.     

Elements,devices, and methods for fractal communication technology,electronics, and nanotechnology

The numerous results obtained in radio physics using fractal theory, fractional dimension, and fractional operators have been briefly classified taking into account the scaling effects of real radio signals and electromagnetic fields. A universal modeling environment based on a multilayer virtual generalized distributed RLCG element and the method of generalized finite distributed elements for analysis and synthesis of models of fractional objects and processes that possess fractional power dependence of the input impedance on frequency have been proposed. Examples of synthesis of one- and two-dimensional models are given. It is shown that nonlinear, parametrical, and other properties of modeled objects can be taken into consideration by means of the vectors of electrophysical parameters of layers and design factors.     

The nanotechnology patent thicket revisited

Despite all predictions and promises, nanotechnology still seems to be more of an emerging science than a fully fledged revolution. More often than not, the patent system is blamed for this, supposedly tangling up nanotechnology in an impenetrable thicket of exclusionary rights instead of setting it free. Drawing on methods of complex network analysis, we provide empirical evidence suggesting that, at least in Europe, there is actually no patent thicket present in nanotechnology. Yet, the situation appears to be different in the USA.     

The seminal literature of nanotechnology research

A generally weak area in research papers, reports, and reviews is the complete identification of seminal background documents that formed the building blocks for these papers. A method for systematically determining these seminal references is presented. Citation-assisted background (CAB) is based on the assumption that seminal documents tend to be highly cited. Application of CAB to the field of nanotechnology research is presented. While CAB is a highly systematic approach for identifying seminal references, it serves as a supplement and is not a substitute for the judgment of the authorsThe views in this paper are solely those of the authors, and do not represent the views of the Department of the Navy or any of its components, or the Institute for Defense Analyses     

JINR CICC in computational chemistry and nanotechnology problems: DL_POLY performance for different communication architectures

This report compares the performance of the DL_POLY general-purpose molecular dynamics simulation package on the LIT JINR computing cluster CICC with various communication systems. The comparison involved two cluster architectures: Gigabit Ethernet and InfiniBand technologies, respectively. The code performance tests include some comparison of the CICC cluster with the special-purpose computer MDGRAPE-3 developed at RIKEN for a high-speed acceleration of the MD (molecular dynamics) without a fixed cutoff. The DL_POLY benchmark covers a set of typical MD system simulations detailed below. The article is published in the original.     

纳米生物技术及其应用

纳米技术的发展使人们可以观测到纳米量级的介观世界，可以直观地了解生物分子的形态和分子间的相互作用，甚至可以操纵生物大分子，得到不同结构的新的生物分子．运用纳米技术制作的纳米器件可以用作疾病诊断与治疗．由纳米量级的超微粒构成的纳米生物材料具有良好生物相容性和一些独特的纳米效应，主要表现为小尺寸效应和表面或界面效应．纳米生物材料与相同组成的微米材料存在非常显著的差异，体现出许多优异的性能和全新的功能．纳米微粒在癌症的监测、治疗，细胞和蛋白质的分离，基因治疗，靶向和缓释控药物等中都有着广泛的应用．     

纳米生物技术及其应用

纳米技术的发展使人们可以观测到纳米量级的介观世界,可以直观地了解生物分子的形态和分子间的相互作用,甚至可以操纵生物大分子,得到不同结构的新的生物分子.运用纳米技术制作的纳米器件可以用作疾病诊断与治疗.由纳米量级的超微粒构成的纳米生物材料具有良好生物相容性和一些独特的纳米效应,主要表现为小尺寸效应和表面或界面效应.纳米生物材料与相同组成的微米材料存在非常显著的差异,体现出许多优异的性能和全新的功能.纳米微粒在癌症的监测、治疗,细胞和蛋白质的分离,基因治疗,靶向和缓释控药物等中都有着广泛的应用.     

The structure and infrastructure of the global nanotechnology literature

Text mining is the extraction of useful information from large volumes of text. A text mining analysis of the global open nanotechnology literature was performed. Records from the Science Citation Index (SCI)/Social SCI were analyzed to provide the infrastructure of the global nanotechnology literature (prolific authors/journals/institutions/countries, most cited authors/papers/journals) and the thematic structure (taxonomy) of the global nanotechnology literature, from a science perspective. Records from the Engineering Compendex (EC) were analyzed to provide a taxonomy from a technology perspective.

• The Far Eastern countries have expanded nanotechnology publication output dramatically in the past decade.
• The Peoples Republic of China ranks second to the USA (2004 results) in nanotechnology papers published in the SCI, and has increased its nanotechnology publication output by a factor of 21 in a decade.
• Of the six most prolific (publications) nanotechnology countries, the three from the Western group (USA, Germany, France) have about eight percent more nanotechnology publications (for 2004) than the three from the Far Eastern group (China, Japan, South Korea).
• While most of the high nanotechnology publication-producing countries are also high nanotechnology patent producers in the US Patent Office (as of 2003), China is a major exception. China ranks 20th as a nanotechnology patent-producing country in the US Patent Office.

     

The current state of public understanding of nanotechnology

The growing importance of nanotechnology in industry and society has not been accompanied by a widespread understanding of the subject among the general public. Simple questions to initially probe the smallest thing that people can see and can think of reveals a divide in the understanding of the general public. A survey of 1500 individuals ranging in age from 6 to 74 has revealed a lack of knowledge of nanotechnology and especially a lack of understanding of the context of nanotechnology in the world that is too small to see. Survey findings are corroborated by in-depth interviews with 400 adults in studies of nanoscience literacy commisioned by University of California, Berkeley and Cornell in 2002 and 2004, respectively. In general, with the exception of 14–28 year olds, over 60% of respondents say they have never heard of nano or nanotechnology. The results suggest that the general public, especially middle-school children, has no firm foundation to understand nanotechnology and likely will continue to be equally impressed by credible scientific information as well as pure fictional accounts of nanotechnology.     

Monitoring nanotechnology using patent classifications: an overview and comparison of nanotechnology classification schemes

Patents are an essential information source used to monitor, track, and analyze nanotechnology. When it comes to search nanotechnology-related patents, a keyword search is often incomplete and struggles to cover such an interdisciplinary discipline. Patent classification schemes can reveal far better results since they are assigned by experts who classify the patent documents according to their technology. In this paper, we present the most important classifications to search nanotechnology patents and analyze how nanotechnology is covered in the main patent classification systems used in search systems nowadays: the International Patent Classification (IPC), the United States Patent Classification (USPC), and the Cooperative Patent Classification (CPC). We conclude that nanotechnology has a significantly better patent coverage in the CPC since considerable more nanotechnology documents were retrieved than by using other classifications, and thus, recommend its use for all professionals involved in nanotechnology patent searches.     

Nanoscience and nanotechnology in Venezuela

Nanoscale research in Venezuela is briefly reviewed, with emphasis on research groups, research lines, and institutions involved. A summary exploration is made of international collaboration through scientific co-authorship, as well of the efforts to build nano capacities, available infrastructure, relationships to the productive sector and a weak presence in Venezuelan public policies, although there is some expectation that the situation may soon begin to change.     

Metal particle combustion and nanotechnology

Metal combustion has received renewed interest largely as a result of the ability to produce and characterize metallic nanoparticles. Much of the highly desirable traits of nanosized metal powders in combustion systems have been attributed to their high specific surface area (high reactivity) and potential ability to store energy in surfaces. In addition, nanosized powders are known to display increased catalytic activity, superparamagnetic behavior, superplasticity, lower melting temperatures, lower sintering temperatures, and higher theoretical densities compared to micron and larger sized materials. The lower melting temperatures can result in lower ignition temperatures of metals. The combustion rates of materials with nanopowders have been observed to increase significantly over similar materials with micron sized particles. A lower limit in size of nanoenergetic metallic powders in some cases may result from the presence of their passivating oxide coating. Consequently, coatings, self-assembled monolayers (SAMs), and the development of composite materials that limit the volume of non-energetic material in the powders have been under development in recent years. After a brief review of the classifications of metal combustion based on thermodynamic considerations and the different types of combustion regimes of metal particles (diffusion vs. kinetic control), an overview of the combustion of aluminum nanoparticles, their applications, and their synthesis and assembly is presented.     

Public perception of nanotechnology

While several studies on the public opinion of nanotechnology have pointed to a rather enthusiastic U.S. public, the public uptake of nanotechnology in Europe is more contained. The results of the Swiss publifocus on nanotechnology reveal a pragmatic attitude of citizens toward the emerging technologies, thus confirming what has been identified as a “balanced approach” in the NanoJury UK.

The changing information environment for nanotechnology: online audiences and content

The shift toward online communication in all realms, from print newspapers to broadcast television, has implications for how the general public consumes information about nanotechnology. The goal of this study is threefold: to investigate who is using online sources for information and news about science and nanotechnology, to examine what the general public is searching for online with regards to nanotechnology, and to analyze what they find in online content of nanotechnology. Using survey data, we find those who report the Internet as their primary source of science and technology news are diverse in age, more knowledgeable about science and nanotechnology, highly educated, male, and more diverse racially than users of other media. In a comparison of demographic data on actual visits by online users to general news and science Web sites, science sites attracted more male, non-white users from the Western region of the United States than news sites did. News sites, on the other hand, attracted those with a slightly higher level of education. Our analysis of published estimates of keyword searches on nanotechnology reveals people are turning to the Internet to search for keyword searches related to the future, health, and applications of nanotechnology. A content analysis of online content reveals health content dominates overall. Comparisons of content in different types of sites—blogs, government, and general sites—are conducted.     

Current situation and industrialization of Taiwan nanotechnology

Nanotechnology is projected to be a very promising field, and the impact of nanotechnology on society is increasingly significant as the research funding and manufactured goods increase exponentially. A clearer picture of Taiwan’s current and future nanotechnology industry is an essential component for future planning. Therefore, this investigation studies the progress of industrializing nanotechnology in Taiwan by surveying 150 companies. Along with understanding Taiwan’s current nanotechnology industrialization, this paper also suggests ways to promote Taiwan’s nanotechnology. The survey results are summarized and serve as the basis for planning a nanotechnology industrialization strategy.     

Multidisciplinary cognitive content of nanoscience and nanotechnology

This article examines the cognitive evolution and disciplinary diversity of nanoscience/nanotechnology (nano research) as expressed through the terminology used in titles of nano journal articles. The analysis is based on the NanoBank bibliographic database of 287,106 nano articles published between 1981 and 2004. We perform multifaceted analyses of title words, focusing on 100 most frequent words or phrases (terms). Hierarchical clustering of title terms reveals three distinct time periods of cognitive development of nano research: formative (1981–1990), early (from 1991 to 1998), and current (after 1998). Early period is characterized by the introduction of thin film deposition techniques, while the current period is characterized by the increased focus on carbon nanotube and nanoparticle research. We introduce a method to identify disciplinary components of nanotechnology. It shows that the nano research is being carried out in a number of diverse parent disciplines. Currently, only 5% of articles are published in dedicated nano-only journals. We find that some 85% of nano research today is multidisciplinary. The case study of the diffusion of several nano-specific terms (e.g., “carbon nanotube”) shows that concepts spread from the initially few disciplinary components to the majority of them in a time span of around a decade. Hierarchical clustering of disciplinary components reveals that the cognitive content of current nanoscience can be divided into nine clusters. Some clusters account for a large fraction of nano research and are identified with such parent disciplines as the condensed matter and applied physics, materials science, and analytical chemistry. Other clusters represent much smaller parts of nano research, but are as cognitively distinct. In the decreasing order of size, these fields are: polymer science, biotechnology, general chemistry, surface science, and pharmacology. Cognitive content of research published in nano-only journals is the closest to nano research published in condensed matter and applied physics journals.     

Resolution of causal paradoxes arising from opposing thermodynamic arrows of time

It was recently shown (L.S. Schulman, Phys. Rev. Lett. 83 (1999) 5419) that systems with opposite thermodynamic arrows of time could have moderate mutual interaction with neither destroying the order of the other. Such interaction includes signaling. Signals, however, may give rise to causal paradoxes, suggesting that “moderate” interaction may be impossible. Using the two-time boundary condition framework, we resolve the paradoxes. In one example, at a macroscopic level, we establish the existence of solutions to the appropriate boundary value problem. This result is extended to a class of microscopic problems. We also produce an example in which microscopic data are given and there is no solution. This is a different kind of resolution: there is no paradox because the events do not happen. Finally we discuss the differences between these cases.     

Scanning probe microscopies, nanoscience and nanotechnology

The symbiotic relationship between nanoscience and nanotechnology and the scanning probe microscopies is analyzed in terms of relating non-contact atomic force microscope (NC-AFM) technology to applications requiring detection, manipulation and fabrication on the molecular scale. The features of NC-AFM in this connection, which facilitate its unique relationship with nanoscale science and technology, are discussed. Specific typical examples are presented of applications where a NC-AFM measurement of a specific physical or chemical property is correlated with position, orientation or location on the atomic scale.