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Near-infrared (NIR) laser annealing is used to write conductive patterns on the surface of polypropylene/multi-walled carbon nanotube nanocomposite (PP/MWCNT) plates. Before irradiation, the surface of the nanocomposite is not conductive due to the partial alignment of the MWCNT, which occurs during injection molding. We observe a significant decrease in the surface sheet resistance using NIR laser irradiation, which we explain by a randomization of the orientation of MWCNTs in the PP matrix melt by NIR laser irradiation. After only 5 s of irradiation, the sheet resistance of PP/MWCNTs, annealed with a laser at a power density of 7 W/cm2, decreases by more than 4 decades from â¼100 MΩ/sq to â¼1 kΩ/sq. Polarized Raman, TEM, and SEM are used to investigate the changes in the sheet resistance and confirm the physico-chemical processes involved. This allows direct writing of conductive patterns using a NIR laser on the surface of nanocomposite polymer substrates, with the advantages of a fast, easy, and low-energy consumption process.
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A metal-oxide material (indium zinc oxide [IZO]) device with near-infrared (NIR) laser annealing was demonstrated on both glass and bendable plastic substrates (polycarbonate, polyethylene, and polyethylene terephthalate). After only 60 s, the sheet resistance of IZO films annealed with a laser was comparable to that of thermal-annealed devices at temperatures in the range of 200-300 °C (1 h). XPS, ATR, and AFM were used to investigate the changes in the sheet resistance and correlate them to the composition and morphology of the thin film. Finally, the NIR-laser-annealed IZO films were demonstrated to be capable of detecting changes in humidity and serving as a highly sensitive gas sensor of hydrogen sulfide (in ppb concentration), with room-temperature operation on a bendable substrate.
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The United States has a high stake in China's serious food safety problem, as food products of Chinese origin have dominated the U.S. food market in numerous areas and continue to grow. The conclusion of the U.S.-China Food Safety Agreement ("the Agreement") has allowed FDA to strengthen regulatory cooperation with its Chinese counterpart in various aspects. The Agreement also paves the way for the implementation of the new regulatory tools incorporated in FSMA, especially in the cross-border context. However, both the Agreement and FSMA have certain crucial limitations that may create future hurdles to effective implementation in the U.S.-China cooperation. This paper therefore endeavors to first examine China's governance challenges over food safety, with a focus on the 2009 Food Safety Law, the 2015 Amendment, and the fundamental problem of "thin" rule of law. This paper moves to analyze the U.S.-China Food Safety Agreement, reviewing the agreement's strengths and weaknesses. It further assesses FSMA's innovative institutional design to regulate imported food products and its limitations. However, both the U.S.-China Food Safety Agreement and FSMA arguably create a regulatory dilemma for FDA when addressing imported food safety, due to structural mismatch between the broad scope of power granted to FDA and the long chain of power outsourcing to governments or private companies as primary "regulators." Neither the Agreement nor FSMA give FDA adequate capacity to closely oversee such "agents" along the chain of power outsourcing. Framing the U.S.-China food safety cooperation as a multilayer structure that "outsources power" to "import safety," this paper concludes by stressing the need for a robust accountability and effective mechanism for U.S.-China food safety cooperation.
Assuntos
Inocuidade dos Alimentos , Doenças Transmitidas por Alimentos/prevenção & controle , Cooperação Internacional , Legislação sobre Alimentos , China , Humanos , Estados UnidosRESUMO
An extensive global system of private food regulation is under construction, one that exceeds conventional regulation thought of as being driven by public authorities like FDA and USDA in the U.S. or the Food Standards Agency in the UK. Agrifood and grocer organizations, in concert with some farming groups, have been the primary designers of this new food regulatory regime. These groups have established alliances that compete with national regulators in complex ways. This article analyzes the relationship between public and private sources of food safety regulation by examining standards adopted by the Codex Alimentarius Commission, a food safety organization jointly run by the Food and Agricultural Organization and the World Health Organization and GlobalG.A.P., a farm assurance program created in the late 1990s by supermarket chains and their major suppliers which has now expanded into a global certifying coalition. While Codex standards are adopted, often as written, by national food safety regulators who are principal drivers of the standard setting process, customers for agricultural products in many countries now demand evidence of GlobalG.A.P. certification as a prerequisite for doing business This article tests not only the durability and strength of private sector standard setting in the food safety system, but also the desirability of that system as an alternative to formal, governmental processes embodied, for our purposes, in the standards adopted by Codex. In many cases, official standards and GlobalG.A.P. standards clash in ways that implicate not only food safety but the flow of agricultural products in the global trading system. The article analyzes current weaknesses in both regimes and possibilities for change that will better reconcile the two competing systems.
Assuntos
Inocuidade dos Alimentos , Legislação sobre Alimentos , Agricultura/normas , Indústria Alimentícia/normas , Doenças Transmitidas por Alimentos/prevenção & controle , Órgãos Governamentais , Humanos , Agências InternacionaisRESUMO
In response to an apparent decline in global food safety, numerous public and private regulatory initiatives have emerged to restore public confidence. This trend has been particularly marked by the growing influence of private regulators such as multinational food companies, supermarket chains and non-governmental organizations (NGOs), who employ private standards, certification protocols, third-party auditing, and transnational contracting practices. This paper explores how the structure and processes of private food safety governance interact with traditional public governance regimes, focusing on Global Good Agricultural Practices (GlobalGAP) as a primary example of the former. Due to the inefficiency and ineffectiveness of public regulation in the face of global problems, private governance in food safety has gradually replaced states' command-and-control regulation with more flexible, market-oriented mechanisms. The paper concludes by emphasizing the importance of constructive regime interaction instead of institutional boundary building to global food safety governance. Public and private ordering must each play a role as integral parts of a larger, dynamic and evolving governance complex.