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61.
Accurate measurement of energy savings from industrial energy efficiency projects can reduce uncertainty about the efficacy of the projects, guide the selection of future projects, improve future estimates of expected savings, promote financing of energy efficiency projects through shared-savings agreements, and improve utilization of capital resources. Many efforts to measure industrial energy savings, or simply track progress toward efficiency goals, have had difficulty incorporating changing weather and production, which are frequently major drivers of plant energy use. This paper presents a general method for measuring plant-wide industrial energy savings that takes into account changing weather and production between the pre and post-retrofit periods. In addition, the method can disaggregate savings into components, which provides additional resolution for understanding the effectiveness of individual projects when several projects are implemented together. The method uses multivariable piece-wise regression models to characterize baseline energy use, and disaggregates savings by taking the total derivative of the energy use equation. Although the method incorporates search techniques, multi-variable least-squares regression and calculus, it is easily implemented using data analysis software, and can use readily available temperature, production and utility billing data. This is important, since more complicated methods may be too complex for widespread use. The method is demonstrated using case studies of actual energy assessments. The case studies demonstrate the importance of adjusting for weather and production between the pre- and post-retrofit periods, how plant-wide savings can be disaggregated to evaluate the effectiveness of individual retrofits, how the method can identify the time-dependence of savings, and limitations of engineering models when used to estimate future savings. 相似文献
62.
Photoinduced Proton Transfer between Photoacid and pH‐Sensitive Dyes: Influence Factors and Application for Visible‐Light‐Responsive Rewritable Paper 下载免费PDF全文
Ting Zhang Lan Sheng Junning Liu Le Ju Jianhua Li Zhen Du Weiran Zhang Minjie Li Sean Xiao‐An Zhang 《Advanced functional materials》2018,28(16)
Ink‐free printing based on rewritable paper is an efficient and environmental friendly way to reuse paper, protect resources, and save energy for sustainable development of human society. Among various kinds of rewritable media, light responsive rewritable paper (LRP) is one of the most popular research areas due to its clean and favorable noncontact writing. Visible light is more suitable for LRP for its superior penetration and much less damages to organic molecules than UV light. However, visible‐light‐responsive rewritable paper (VLRP) has only limited successes so far. Herein, a VLRP is newly designed and fabricated based on photoinduced proton transfer (PPT) between photoacid and pH‐sensitive dyes. Success of it is highly benefited from systematical investigation and in‐depth understanding on the key influence factors, such as concentration‐induced undesired isomerization, temperature, humidity, and light intensity, on the PPT and its inverse process. As‐prepared VLRP shows long‐awaited properties, such as, high color contrast and resolution, appropriate legible time of prints, excellent reversibility (>100 cycles), easiness to achieve multicolor prints, and agreeing well with environmental concept of green printing. In addition, study of influence factors on PPT in this work, to some extent, may also help people understand complex photocycle process in biosystem. 相似文献
63.
Vibrational Energy Transport in Hybrid Ordered/Disordered Nanocomposites: Hybridization and Avoided Crossings of Localized and Delocalized Modes 下载免费PDF全文
Taishan Zhu Krishnan Swaminathan‐Gopalan Kevin J. Cruse Kelly Stephani Elif Ertekin 《Advanced functional materials》2018,28(17)
Vibrational energy transport in disordered media is of fundamental importance to several fields spanning from sustainable energy to biomedicine to thermal management. This work investigates hybrid ordered/disordered nanocomposites that consist of crystalline membranes decorated by regularly patterned disordered regions formed by ion beam irradiation. The presence of the disordered regions results in reduced thermal conductivity, rendering these systems of interest for use as nanostructured thermoelectrics and thermal device components, yet their vibrational properties are not well understood. Here, the mechanism of vibrational transport and the reason underlying the observed reduction is established in detail. The hybrid systems are found to exhibit glass‐crystal duality in vibrational transport. Lattice dynamics reveals substantial hybridization between the localized and delocalized modes, which induces avoided crossings and harmonic broadening in the dispersion. Allen/Feldman theory shows that the hybridization and avoided crossings are the dominant drivers of the reduction. Anharmonic scattering is also enhanced in the patterned nanocomposites, further contributing to the reduction. The systems exhibit features reminiscent of both nanophononic materials and locally resonant nanophononic metamaterials, but operate in a manner distinct to both. These findings indicate that such “patterned disorder” can be a promising strategy to tailor vibrational transport through hybrid nanostructures. 相似文献
64.
Identification of Multiple Dityrosine Bonds in Materials Composed of the Drosophila Protein Ultrabithorax 下载免费PDF全文
65.
66.
Maarten Nijland Antony George Sean Thomas Evert P. Houwman Jing Xia Dave H. A. Blank Guus Rijnders Gertjan Koster Johan E. ten Elshof 《Advanced functional materials》2014,24(43):6853-6861
A process is developed that combines soft lithographic molding with pulsed laser deposition (PLD) to make heteroepitaxial patterns of functional perovskite oxide materials. Micro‐ and nanostructures of sacrificial ZnO are made by micro molding in capillaries (MiMiC) and nano transfer molding, respectively, and used to screen the single crystalline substrates during subsequent PLD. ZnO is used because of its compatibility with the high temperatures reached during PLD and because of the ease of its removal after use by benefiting from its amphoteric nature. Sub‐micrometer sized lines of La0.67Sr0.33MnO3 are made by the transfer molding approach, preserving the anisotropic features expected for a fully oriented thin film and taking account for the magnetostatic contribution from the line shapes. Different patterns of SrRuO3 are made with lateral dimensions of a few micrometers having individual features for which electrical isolation is illustrated. The bottom‐up soft lithographic methods can be compliantly utilized for making epitaxial structures of various shapes and sizes in the μm down to the nm range, and offer unique opportunities for fundamental studies as well as for realizing technological applications. 相似文献
67.
Kelly N. L. Huggins Alia P. Schoen Manickam Adhimoolam Arunagirinathan Sarah C. Heilshorn 《Advanced functional materials》2014,24(48):7737-7744
The use of biological scaffolds to template inorganic material offers a strategy to synthesize precise composite nanostructures of different sizes and shapes. Proteins are unique biological scaffolds that consist of multiple binding regions or epitope sites that site‐specifically associate with conserved amino acid sequences within protein‐binding partners. These binding regions can be exploited as synthesis sites for multiple inorganic species within the same protein scaffold, resulting in bimetallic inorganic nanostructures. This strategy is demonstrated with the scaffold protein clathrin, which self‐assembles into spherical cages. Specifically, tether peptides that noncovalently associate with distinct clathrin epitope sites, while initiating simultaneous synthesis of two inorganic species within the assembled clathrin protein cage, are designed. The flexibility and diversity of this unique biotemplating strategy is demonstrated by synthesizing two types of composite structures (silver–gold mixed bimetallic and silver–gold core–shell nanostructures) from a single clathrin template. This noncovalent, Template Engineering Through Epitope Recognition, or TEThER, strategy can be readily applied to any protein system with known epitope sites to template a variety of bimetallic structures without the need for chemical or genetic mutations. 相似文献
68.
Isabella S. Romero Nathan P. Bradshaw Jesse D. Larson Sean Y. Severt Sandra J. Roberts Morgan L. Schiller Janelle M. Leger Amanda R. Murphy 《Advanced functional materials》2014,24(25):3866-3873
Single‐component, metal‐free, biocompatible, electromechanical actuator devices are fabricated using a composite material composed of silk fibroin and poly(pyrrole) (PPy). Chemical modification techniques are developed to produce free‐standing films with a bilayer‐type structure, with unmodified silk on one side and an interpenetrating network (IPN) of silk and PPy on the other. The IPN formed between the silk and PPy prohibits delamination, resulting in a durable and fully biocompatible device. The electrochemical stability of these materials is investigated through cyclic voltammetry, and redox sensitivity to the presence of different anions is noted. Free‐end bending actuation performance and force generation within silk‐PPy composite films during oxidation and reduction in a biologically relevant environment are investigated in detail. These silk–PPy composites are stable to repeated actuation, and are able to generate forces comparable with natural muscle (>0.1 MPa), making them ideal candidates for interfacing with biological tissues. 相似文献
69.
70.
J. T. Reilly C. N. Schubert J. R. Lindner M. D. Donohue R. M. Kelly 《Chemical Engineering Communications》1990,93(1):181-191
Absorption rates of carbonyl sulfide and carbon dioxide into aqueous methyldiethanolamine solutions with and without heterocyclic amine additives were measured in a stirred cell apparatus. All of the heterocyclic amine additives catalyzed COS absorption more strongly than that for CO2. In instances in which absorption rates were improved by the additives, those with the lowest pKb's were the most effective, although steric factors also apparently influence reaction kinetics. 相似文献