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Screen-printed membrane sensors based on the use of paper and ceramic substrates are fabricated, characterized, and used for rapid batch and continuous monitoring of CrIII in the form of CrO42&minus, in some industrial products and wastewater samples. Strips of paper and ceramic platforms (15 &times, 5 mm) were covered with conductive carbon paint and then modified with polyaniline (PANI) film, to act as an ion-to-electron transducer, followed by a drop casting of plasticized poly (vinyl chloride) (PVC) Rhodamine-B chromate membrane as a recognition sensing material. In a 5.0 mmol L&minus, 1 Trizma buffer solution of pH ~8, the fabricated paper and ceramic based membrane sensors exhibited a near Nernstian response for CrVI ion with slopes of &minus, 29.7 &plusmn, 0.5 and &minus, 28.6 &plusmn, 0.3 mV decade&minus, 1, limit of detection 2.5 &times, 10&minus, 5 and 2.4 &times, 6 mol L&minus, 1 (1.3&ndash, 0.12 &micro, g mL&minus, 1), and linear concentration range 7.5 &times, 3&ndash, 5.0 &times, 5 and 7.5 &times, 1.0 &times, 5 mol L&minus, 1 (390-0.5 &micro, 1), respectively. Both sensors exhibited fast and stable potentiometric response, excellent reproducibility, and good selectivity with respect to a number of common foreign inorganic species. Impedance spectroscopy and chronopotentiometry data revealed a small resistance and a larger double layer capacitance due to the presence of the intermediate polyaniline (PAN) conductive layer. Furthermore, the formation of a water layer between the ion selective membrane (ISM) and the underlying conductor polymer and between the conducting polymer and the carbon conducting surface was greatly reduced. The developed disposable solid-contact potentiometric sensors offer the advantages of simple design, long term potential stability, flexibility, miniaturization ability, short conditioning time, and cost effectiveness that enable mass production. The sensors were successfully used for static and hydrodynamic measurements of total chromium in some leather tanning wastewater and nickel-chrome alloy samples. The results compare favorably with data obtained by atomic absorption spectrometry.

Made available in DSpace on 2015-10-22T06:23:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-01. Added 1 bitstream(s) on 2015-10-22T09:46:14Z : No. of bitstreams: 1 WOS000348297200004.pdf: 1099720 bytes, checksum: b9752354f4e5c45985ed2a579f391092 (MD5) Automotive heat shields are usually composed of two metal sheets enclosing an insulating material with a paper-like texture that contains refractory ceramic particles. This article discusses the results achieved by recycling the scrap automotive insulation that is discarded in landfills, using the same concept as paper recycling. For comparison with the original product, tests of thickness, bulk density, weight loss on ignition, tensile strength, compressibility, and recovery were performed on recycled materials produced in a so-called "manual" process (involving little automation and performed in adapted facilities) without pressing, and pressed once, twice, and four times. Materials recycled in a so-called "industrial" process (in a paper recycling plant) without pressing, and pressed once were also tested. The recycled materials can be considered approved with respect to the main requirement, thermal insulation, since they dissipated the under-hood temperature by more than 300 A degrees C (like the original product). Like the heat insulation tests, the thermogravimetric analysis suggested that the recycled materials showed higher stability than the original product. Thermogravimetric, microscopy, and energy dispersive spectroscopy analyses indicated that the structural and compositional characteristics of the original product were preserved after recycling. Univ Estadual Paulista, UNESP, BR-18087180 Sorocaba, SP, Brazil Univ Fed Sao Carlos, UFSCar, BR-18052780 Sorocaba, SP, Brazil Univ Estadual Paulista, UNESP, BR-18087180 Sorocaba, SP, Brazil

Low-temperature, solution-based self-assembly of vanadia nanofibers yields a free-standing, ceramic paper with an outstanding combination of high strength, stiffness, and macroscopic flexibility. Its excellent mechanical performance results from a brick-and-mortar like architecture, which combines strong covalent bonding within the single-crystalline nanofibers with an intricate hydrogen bonding network between them.

Polymers and papers, which exhibit piezoelectricity, find a wide range of applications in the industry. Ever since the discovery of PVDF, piezo polymers and papers have been widely used for sensor and actuator design. The direct piezoelectric effect has been used for sensor design, whereas the inverse piezoelectric effect has been applied for actuator design. Piezo polymers and papers have the advantages of mechanical flexibility, lower fabrication cost and faster processing over commonly used piezoelectric materials, such as PZT, BaTiO3. In addition, many polymer and paper materials are considered biocompatible and can be used in bio applications. In the last 20 years, heterostructural materials, such as polymer composites and hybrid paper, have received a lot of attention since they combine the flexibility of polymer or paper, and excellent pyroelectric and piezoelectric properties of ceramics. This paper gives an overview of piezoelectric polymers and papers based on their operating principle. Main categories of piezoelectric polymers and papers are discussed with a focus on their materials and fabrication techniques. Applications of piezoelectric polymers and papers in different areas are also presented.

A novel paper-based material containing titanium dioxide (TiO(2)) photocatalyst was successfully prepared by a papermaking technique with the internal addition of inorganic fibers on which TiO(2) particles were supported. Photodegradation performance of acetaldehyde gas, an indoor pollutant, and the durability of the TiO(2)-containing papers were investigated under UV irradiation. Ceramic fiber suspension and polydiallyldimethylammonium chloride as a cationic flocculant were mixed, followed by the addition of TiO(2) suspension and anionic polyacrylamide. Subsequently, the inorganic mixture was poured into a pulp suspension, and TiO(2) handsheets then prepared by a papermaking method. The tensile strength of TiO(2)-containing paper without a ceramic carrier decreased by more than 30% after 240-h UV irradiation (2 mW/cm(2)), although the strength of the TiO(2) sheet with ceramic fibers remained reasonably stable. The efficiency of acetaldehyde decomposition by the TiO(2) paper containing an inorganic carrier was nearly equal to that of the carrier-free TiO(2) paper. Scanning electron microscopic observation suggested that most TiO(2) particles were predominantly supported on the inorganic fiber matrix, and were mostly out of contact with organic pulp fibers. The TiO(2) paper with an inorganic carrier demonstrated both excellent photocatalytic performance and durability, which before had been mutually incompatible for organic materials containing TiO(2) photocatalyst. The two-stage mixing procedure for TiO(2) sheet-making is promising for the simple manufacture of high performance paper with photocatalytic ability.

Titanium dioxide (TiO2) photocatalyst and zeolite adsorbent were made into a paper-like composite by a papermaking technique using pulp and ceramic fibers as sheet matrix. The photocatalytic performance for the degradation of bisphenol A (BPA) dissolved in water was investigated under UV irradiation. The TiO2 sheet prepared was easier to handle than the original TiO2 powders in aqueous media. The TiO2 sheet could decompose the BPA under UV irradiation, although at a lower degradation efficiency than the TiO2 suspension. The TiO2-free zeolite sheet could not remove the BPA from water completely because of its adsorption equilibrium. Furthermore, the composite TiO2-zeolite sheets exhibited a higher efficiency for BPA removal than the zeolite-free TiO2 sheets, the efficiency of the former being equivalent to that of the TiO2 suspension. The enhancement in removal efficiency was not attributed to the simple adsorption of BPA on zeolite but rather to the synergistic effect obtained through the combined use of TiO2 photocatalyst and zeolite adsorbent in the paper-like composite sheet, which is believed to accelerate the BPA photodegradation in water.

This paper reviews recent studies by the authors on the surface characterization of biomedically significant materials through electroosmosis determination. The surfaces studied include transparent and nontransparent materials such as quartz, ceramics, paper, and cast polymer capillaries, slides, and particles, in both native and surface modified form. The method is nondestructive, relatively fast, mechanistically simple, automatable to varying degrees, and can be used to analyze samples under physiologically compatible conditions. New experimental and mathematical modeling approaches allow estimates to be obtained with regard to the surface density and pK of various chemical groups, as well as the thickness of polymer or other surface coatings. Surface modifications which may be characterized include, covalent alteration via radiofrequency plasma discharge or organosilane grafting, noncovalent alteration via polymer adsorption, and covalent grafting of neutral polymers, such as poly(ethylene glycol) or dextran. Results complement those from other surface analysis techniques, and correlate with physiologically significant phenomena such as protein adsorption.

The arrival of the Southern Pacific Railroad in Tucson on 20 March 1880, dramatically changed the community. Historic Block 83 was located across the street from the railroad depot and developed rapidly in response to the sudden influx of departing or arriving travelers. Boarding houses, a hotel, saloons, restaurants, barber shops, a pool hall, a Chinese laundry, and several small stores were among the businesses that catered to these people. The southeastern corner of the block was associated with a small group of Austrian immigrant businessmen, as well as several African-American barbers. Biographical research has provided new information about these groups. Archaeological excavations uncovered several hundred features dating to the late nineteenth and early twentieth centuries; these included the foundations of structures. More common were features dug into the backyards of the four blocks. Privy pits and wells were common, many providing large samples of trash discarded by businesses. Unfortunately, about half of those located had been looted by bottle hunters in the 1960s and 1970s. A particularly interesting find was the set of planting pits for the trees that once shaded the Depot Beer Garden. A very large assemblage of artifacts and food remains were recovered. Many items originated in the Cactus Saloon, the Depot Park Hotel (later the Ramona Hotel), and the Quong Wo Chinese-operated laundry. These items provided valuable insights into the history and material culture of saloons and other businesses in Tucson. Plans to redevelop Lots 8, 9, 12, and 16 led to archaeological testing and data recovery excavations in this area at AZ BB:13:401 (ASM). Several hundred features were revealed and over 100,000 artifacts were recovered. Results of the project are summarized in this report.

TiO2 powder-containing paper composites, called TiO2 paper, were prepared by a papermaking technique, and their photocatalytic efficiency was investigated. The TiO2 paper has a porous structure originating from the layered pulp fiber network, with TiO2 powders scattered on the fiber matrix. Under UV irradiation, the TiO2 paper decomposed gaseous acetaldehyde more effectively than powdery TiO2 and a pulp/TiO2 mixture not in paper form. Scanning electron microscopy and mercury intrusion analysis revealed that the TiO2 paper had characteristic unique voids ca. 10 μm in diameter, which might have contributed to the improved photocatalytic performance. TiO2 paper composites having different void structures were prepared by using beaten pulp fibers with different degrees of freeness and/or ceramic fibers. The photodecomposition efficiency was affected by the void structure of the photocatalyst paper, and the initial degradation rate of acetaldehyde increased with an increase in the total pore volume of TiO2 paper. The paper voids presumably provided suitable conditions for TiO2 catalysis, resulting in higher photocatalytic performance by TiO2 paper than by TiO2 powder and a pulp/TiO2 mixture not in paper form.

Surface sol-gel process was used to replicate the hierarchical morphology of natural cellulosic substances with nanometer precision. The resultant artificial fossils are ceramic nanomaterials composed of metal oxide nanotubes.

15 mi of Extra High Voltage transmission line corridor, 2 mi of access road, and 0.9 mi of 115kV transmission line from the Silverking Substation were surveyed for archaeological resources by the Museum of Northern Arizona in April, 1978. Twelve prehistoric and historic Anglo-American affiliation archaeological sites were identified along the EHV corridor between the Silverking Substation and the Tonto National Forest boundary. An isolated recent feature, not given a site designation, was found on the proposed access road alignment. No sites were found on the 115kV alignment. The report describes the survey and its results and makes detailed archaeological clearance recommendations for the surveyed impact areas. Archaeological clearance is recommended for all surveyed areas except for the actual areas of the 12 recorded sites in the EHV corridor.