670 research outputs found
Probing viscoelastic properties of a thin polymer film sheared between a beads layer and quartz crystal resonator
We report measurements of viscoelastic properties of thin polymer films of
10-100 nm at the MHz range. These thin films are confined between a quartz
crystal resonator and a millimetric bead layer, producing an increase of both
resonance frequency and dissipation of the quartz resonator. The shear modulus
and dynamic viscosity of thin films extracted from these measurements are
consistent with the bulk values of the polymer. This modified quartz resonator
provides an easily realizable and effective tool for probing the rheological
properties of thin films at ambient environment.Comment: submitted to ap
Investigation of Polymer–Plasticizer Blends as SH-SAW Sensor Coatings for Detection of Benzene in Water with High Sensitivity and Long-Term Stability
We report the first-ever direct detection of benzene in water at concentrations below 100 ppb (parts per billion) using acoustic wave (specifically, shear-horizontal surface acoustic wave, SH-SAW) sensors with plasticized polymer coatings. Two polymers and two plasticizers were studied as materials for sensor coatings. For each polymer–plasticizer combination, the influence of the mixing ratio of the blend on the sensitivity to benzene was measured and compared to commercially available polymers that were used for BTEX (benzene, toluene, ethylbenzene, and xylene) detection in previous work. After optimizing the coating parameters, the highest sensitivity and lowest detection limit for benzene were found for a 1.25 μm thick sensor coating of 17.5%-by-weight diisooctyl azelate-polystyrene on the tested acoustic wave device. The calculated detection limit was 45 ppb, with actual sensor responses to concentrations down to 65 ppb measured directly. Among the sensor coatings that showed good sensitivity to benzene, the best long-term stability was found for a 1.0 μm thick coating of 23% diisononyl cyclohexane-1,2-dicarboxylate-polystyrene, which was studied here because it is known to show no detectable leaching in water. The present work demonstrates that, by varying type of plasticizer, mixing ratio, and coating thickness, the mechanical and chemical properties of the coatings can be conveniently tailored to maximize analyte sorption and partial chemical selectivity for a given class of analytes as well as to minimize acoustic-wave attenuation in contact with an aqueous phase at the operating frequency of the sensor device
Gas loading of graphene-quartz surface acoustic wave devices
Copyright © 2013 AIP PublishingGraphene was transferred to the propagation path of quartz surface acoustic wave devices and the attenuation due to gas loading of air and argon measured at 70 MHz and 210 MHz and compared to devices with no graphene. Under argon loading, there was no significant difference between the graphene and non-graphene device and the values of measured attenuation agree well with those calculated theoretically. Under air loading, at 210 MHz, there was a significant difference between the non-graphene and graphene devices, with the average value of attenuation obtained with the graphene devices being approximately twice that obtained from the bare quartz devices.Royal Societ
Europeanising advisory expertise: The role of 'independent, objective and transparent' scientific advice in agri-biotech regulation
Since various crises of food safety in the European Union (EU), institutional reforms have been designed to regain public confidence in regulatory decisions and their expert basis. By Europeanising advisory expertise, the European Food Safety Authority (EFSA) was also meant to help harmonise 'science-based regulation' and thus facilitate EU decisions. In evaluating agri-biotech products during 2003-2005, however, the EFSA procedure extended previous expert disagreements rather than overcome them. EFSA was designed to demonstrate that expert advice would be 'independent, objective and transparent�; yet tensions arose between expert experience versus independence, between transparency versus objectivity, and between harmonisation versus precaution. These conflicts have been shaped by the dominant problem-diagnosis, which favours a narrow expert consensus within a specific policy view. Alternative problem-diagnoses suggest that expertise should instead be pluralised, so that norms and uncertainties become more explicit. Pressure for EU reform manifests tensions between the dominant and alternative problem-diagnoses
Motif Minang Kaluak Paku Kacang Balimbiang pada Busana Kasual
Minangkabau sebagai salah satu suku bangsa yang mengisi kekhasan
budaya Indonesia memiliki warisan budaya yang terpencar dalam berbagai aspek
kehidupannya. Salah satu warisan budaya adalah seni ukir. Seni ukir yang
dikembangkan dengan mengambil ide dari alam memiliki makna-makna filosofi
bagi kehidupan masyarakat Minangkabau. Semua jenis ukiran yang dipahatkan di
Rumah Gadang menunjukkan unsur penting pembentuk budaya Minangkabau
bercerminkan kepada apa yang ada di alam. Salah satu ukiran pada rumah gadang
yaitu kaluak paku. Kaluak paku adalah nama salah satu motif ukiran dalam adat
Minangkabau. Berasal dari motif gulungan (kelukan/kaluak) pada ujung tanaman
pakis (paku) yang masih muda. Ukiran kaluak paku rumah gadang melambangkan
tanggung jawab seorang lelaki dalam adat Minangkabau kepada generasi penerus,
sebagai ayah dari anak-anaknya dan sebagai mamak dari kemenakan (keponakan).
Ukiran rumah gadang kaluak paku minangkabau inilah yang menjadi sumber ide
penciptaan busana pada tugas akhir ini.
Pada Penciptaan karya ini menggunakan beberapa metode, yaitu metode
pendekatan estetis dan ergonomis, metode pengumpulan data dengan studi
pustaka, dan motode penciptaan dengan teori Gustami Sp 3 tahap 6 Langkah.
Dalam proses pembuatan karya dibutuhkan beberapa data, cara pengumpulan data
acuan berdasarkan pengumpulan data pustaka yaitu berupa buku, jurnal pada
media sosial, serta aplikasi pada smartphone seperti pinterest. Data yang
dikumpulkan yang paling utama adalah gambar bentuk visual dari ukiran tanaman
kaluak paku minangkabau dan busana kasual.
Penciptaan karya yang dihasilkan yaitu berupa 8 busana kasual. Siluet pada
kesuluruhan hasil karya yaitu memiliki siluet A yang mengembang pada bagian
bawah. Pada penciptaan karya ini menggunakan bahan utama primisima.
Perpaduan warna yang diterapkan menggunakan warna khas minangkabau yang
diambil dari warna bendera adatnya “marawa” yaitu merah, hitam, dan kuning.
Karya- karya yang dihasilkan dengan penggunaan warna tersebut sangat sesuai
dengan tema yang mengangkat ukiran rumah gadang kaluak paku minangkabau.
Kata Kunci : Minang, Kaluak Paku Kacang Balimbiang, Kasua
Deep-water macroalgae from the Canary Islands: new records and biogeographical relationships
Due to the geographical location and paleobiogeography of the Canary Islands, the
seaweed flora contains macroalgae with different distributional patterns. In this contribution, the biogeographical relations of several new records of deep-water macroalgae recently collected around the Canarian archipelago are discussed. These are Bryopsidella neglecta (Berthotd) Rietema,Discosporangium mesarthrocarpum (Meneghini) Hauck, Hincksia onslowensis (Amsler et Kapraun)P.C. Silva, Syringoderma floridana Henry, Peyssonnelia harveyana J. Agardh, Cryptonemia seminervis(C. Agardh) J. Agardh, Botryodadia wynnei Ballantine, Gloiocladia blomquistii (Searles) R. E.Norris, PIahchrysis peltata (W. R. Taylor) P. Huv4 et H. Huv4, Leptofauchea brasiliensis Joly, and Sarcodiotheca divaricata W. R. Taylor. These new records, especially those in the Florideophyceae,support the strong affinity of the Canary Islands seaweed flora with the warm-temperate Mediterranean-Atlantic region. Some species are recorded for the first time from the east coast of the Atlantic Ocean, enhancing the biogeographic relations of the Canarian marine flora with that of the western Atlantic regions
Eco-engineered rock pools: a concrete solution to biodiversity loss and urban sprawl in the marine environment
journal_title: Environmental Research Letters article_type: lett article_title: Eco-engineered rock pools: a concrete solution to biodiversity loss and urban sprawl in the marine environment copyright_information: © 2016 IOP Publishing Ltd license_information: cc-by Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. date_received: 2016-05-12 date_accepted: 2016-08-10 date_epub: 2016-09-1
“Working the System”—British American Tobacco's Influence on the European Union Treaty and Its Implications for Policy: An Analysis of Internal Tobacco Industry Documents
Katherine Smith and colleagues investigate the ways in which British American Tobacco influenced the European Union Treaty so that new EU policies advance the interests of major corporations, including those that produce products damaging to health
Redox properties of the iron-sulfur clusters in activated Fe-hydrogenase from Desulfovibrio vulgaris (Hildenborough)
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65750/1/j.1432-1033.1992.tb17261.x.pd
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