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91.
Joseph Fiksel Bhavik R. Bakshi Anil Baral Erika Guerra Bernhard DeQuervain 《Clean Technologies and Environmental Policy》2011,13(1):19-35
Life cycle assessment is used to determine the most environmentally beneficial alternatives for reuse of scrap tires, based
on the concept of industrial ecology. Unutilized scrap tires can be a major source of pollution, and in the past decade Federal
and state governments in the United States have encouraged the recycling and reuse of scrap tires in a number of applications,
ranging from energy recovery to civil engineering materials to utilization of ground rubber in manufacturing. Life cycle inventory
data are collected from primary industry sources as well as published literature, and life cycle impact analysis is performed
using the TRACI tool. The results indicate that beneficial reuse of scrap tires, particularly in cement plants and artificial
turf, provides reductions in greenhouse gas (GHG) emissions, air toxics, and water consumption. For example, every metric
ton of tire-derived fuel substituted for coal in cement kilns avoids an estimated 543 kg (CO2 equivalent) of direct and indirect GHG emissions. Taking into account the deductible CO2 from natural rubber, the avoided GHG emissions would be 613 CO2 kg eq. per metric ton. The use of scrap tires for fuel in cement plants provides more reductions in most environmental impact
categories compared to other scrap tire applications, excluding application in artificial turf. Although the use of ground
rubber for artificial turf offers the greatest environmental emission reductions, it has limited potential for large-scale
utilization due to the saturated market for artificial turf. Therefore, the use of fuel derived from scrap tires in cement
production appears to be an attractive option in view of its large market capacity and significant potential for environmental
impact reductions. 相似文献
92.
We report on a novel miniaturized Ag/Ag+ reference electrode (RE) design suitable for electrochemical measurements in room temperature ionic liquids (RTILs). The electrode is based on capillaries with an outer diameter of 365 μm and contains a 10 mmol/l solution of a silver salt in a RTIL. The silver salt bears the same type of anion as the RTIL. While potential shifts of several hundred millivolts have been observed for common platinum or silver pseudo-reference electrodes, our Ag/Ag+ micro electrode provides a stable and reliable reference potential over a period of more than two weeks, if protected from light and stored in a nitrogen atmosphere. Due to the small dimensions of the RE, it can be placed close to the working electrode (WE) and it is well-suited for application in electrochemical micro cells as well as for potential-controlled in situ AFM, STM or electrochemical impedance measurements. The electrode characteristics were determined by voltammetric measurements on ferrocene and cobaltocenium hexafluorophosphate dissolved in a RTIL. The highest expected contamination of the sample with Ag+ ions was calculated and found to be below 4 ppm. 相似文献
93.
John Eckelt Anja Knopf Thomas Röder Hedda K. Weber Herbert Sixta Bernhard A. Wolf 《应用聚合物科学杂志》2011,119(2):670-676
The intrinsic viscosities, [η], of nine cellulose samples, with molar masses from 50 × 103 to 1 390 × 103 were determined in the solvents NMMO*H2O (N‐methyl morpholin N‐oxide hydrate) at 80°C and in cuen (copper II‐ethlenediamine) at 25°C. The evaluation of these results with respect to the Kuhn–Mark–Houwink relations shows that the data for NMMO*H2O fall on the usual straight line in the double logarithmic plots only for M ≤ 158 103; the corresponding [η]/M relation reads log ([η]/mL g−1) = –1.465 + 0.735 log M. Beyond that molar mass [η] remains almost constant up to M ≈ 106 and increases again thereafter. In contrast to NMMO*H2O the cellulose solutions in cuen behave normal and the Kuhn–Mark–Houwink relation reads log ([η]/mL g−1) = −1.185 + 0.735 log M. Possible reasons for the dissimilarities of the behavior of cellulose in these two solvents are being discussed. The comparison of three different methods for the determination of [η] from viscosity measurements at different polymer concentrations, c, demonstrates the advantages of plotting the natural logarithm of the relative viscosities as a function of c. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
94.
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96.
Alex Frano Eva Benckiser Yi Lu Meng Wu Miguel Castro‐Colin Manfred Reehuis Alexander V. Boris Eric Detemple Wilfried Sigle Peter van Aken Georg Cristiani Gennady Logvenov Hanns‐Ulrich Habermeier Peter Wochner Bernhard Keimer Vladimir Hinkov 《Advanced materials (Deerfield Beach, Fla.)》2014,26(2):258-262
97.
98.
Jing Hu Pengfei Liu Bernhard Steinauer 《Frontiers of Structural and Civil Engineering》2017,11(3):329-337
The aim of this paper is investigating the microstructural characteristics of asphalt mixture under different compaction powers. In order to achieve this aim, a test track was built to provide asphalt mixture specimens and X-ray computed tomography (XCT) device was used to scan the internal structure. The aggregate particles and air-voids were extracted using Digital Image Processing (DIP), so the relationship between compaction and air-voids was determined at first, and then, the effect of aggregate particles on the morphology of air-voids can be evaluated, finally, fatigue properties of asphalt mixture with different air-void ratio were measured by indirect tensile fatigue test as well. The research results release the distribution of microstructures in asphalt pavement. 3D fractal dimension is an effective indicator to quantize the complexity of aggregate particles and air-voids; suffering the same compaction power, aggregates cause different constitutions of air-voids in asphalt mixture; investigation in this paper can present the essential relationship between microstructures and fatigue properties. 相似文献
99.
Organometallic DNA–B12 Conjugates as Potential Oligonucleotide Vectors: Synthesis and Structural and Binding Studies with Human Cobalamin-Transport Proteins 下载免费PDF全文
Dr. Elena Mutti Dr. Miriam Hunger Dr. Sergey Fedosov Prof. Dr. Ebba Nexo Prof. Dr. Bernhard Kräutler 《Chembiochem : a European journal of chemical biology》2017,18(22):2280-2291
The synthesis and structural characterization of Co-(dN)25-Cbl (Cbl: cobalamin; dN: deoxynucleotide) and Co-(dN)39-Cbl, which are organometallic DNA–B12 conjugates with single DNA strands consisting of 25 and 39 deoxynucleotides, respectively, and binding studies of these two DNA–Cbl conjugates to three homologous human Cbl transporting proteins, transcobalamin (TC), intrinsic factor (IF), and haptocorrin (HC), are reported. This investigation tests the suitability of such DNA–Cbls for the task of eventual in vivo oligonucleotide delivery. The binding of DNA–Cbl to TC, IF, and HC was investigated in competition with either a fluorescent Cbl derivative and Co-(dN)25-Cbl, or radiolabeled vitamin B12 (57Co-CNCbl) and Co-(dN)25-Cbl or Co-(dN)39-Cbl. Binding of the new DNA–Cbl conjugates was fast and tight with TC, but poorer with HC and IF, which extends a similar original finding with the simpler DNA–Cbl, Co-(dN)18-Cbl. The contrasting affinities of TC versus IF and HC for the DNA–Cbl conjugates are rationalized herein by a stepwise mechanism of Cbl binding. Critical contributions to overall affinity result from gradual conformational adaptations of the Cbl-binding proteins to the DNA–Cbl, which is first bound to the respective β domains. This transition is fast with TC, but slow with IF and HC, with which weaker binding results. The invariably tight interaction of the DNA–Cbl conjugates with TC makes the Cbl moiety a potential natural vector for the specific delivery of oligonucleotide loads from the blood into cells. 相似文献
100.