bluuebunny/crossref_metadata_2025_split huggingface dataset:
An analytical thermohydraulic model for discretely fractured geothermal reservoirs
Authors: Fox Don B. , Koch Donald L. , Tester Jefferson W. 
Published: August 2016

AbstractIn discretely fractured reservoirs such as those found in Enhanced/Engineered Geothermal Systems (EGS), knowledge of the fracture network is important in understanding the thermal hydraulics, i.e., how the fluid flows and the resulting temporal evolution of the subsurface temperature. The purpose of this study was to develop an analytical model of the fluid flow and heat transport in a discretely fractured network that can be used for a wide range of modeling applications and serve as an alternative analysis tool to more computationally intensive numerical codes. Given the connectivity and structure of a fracture network, the flow in the system was solved using a linear system of algebraic equations for the pressure at the nodes of the network. With the flow determined, the temperature in the fracture was solved by coupling convective heat transport in the fracture with one‐dimensional heat conduction perpendicular to the fracture, employing the Green's function derived solution for a single discrete fracture. The predicted temperatures along the fracture surfaces from the analytical solution were compared to numerical simulations using the TOUGH2 reservoir code. Through two case studies, we showed the capabilities of the analytical model and explored the effect of uncertainty in the fracture apertures and network structure on thermal performance. While both sources of uncertainty independently produce large variations in production temperature, uncertainty in the network structure, whenever present, had a predominant influence on thermal performance.
Joint inversion of hydraulic head and self‐potential data associated with harmonic pumping tests
Authors: Soueid Ahmed A. , Jardani A. , Revil A. , Dupont J. P. 
Published: August 2016

AbstractHarmonic pumping tests consist in stimulating an aquifer by the means of hydraulic stimulations at some discrete frequencies. The inverse problem consisting in retrieving the hydraulic properties is inherently ill posed and is usually underdetermined when considering the number of well head data available in field conditions. To better constrain this inverse problem, we add self‐potential data recorded at the ground surface to the head data. The self‐potential method is a passive geophysical method. Its signals are generated by the groundwater flow through an electrokinetic coupling. We showed using a 3‐D saturated unconfined synthetic aquifer that the self‐potential method significantly improves the results of the harmonic hydraulic tomography. The hydroelectric forward problem is obtained by solving first the Richards equation, describing the groundwater flow, and then using the result in an electrical Poisson equation describing the self‐potential problem. The joint inversion problem is solved using a reduction model based on the principal component geostatistical approach. In this method, the large prior covariance matrix is truncated and replaced by its low‐rank approximation, allowing thus for notable computational time and storage savings. Three test cases are studied, to assess the validity of our approach. In the first test, we show that when the number of harmonic stimulations is low, combining the harmonic hydraulic and self‐potential data does not improve the inversion results. In the second test where enough harmonic stimulations are performed, a significant improvement of the hydraulic parameters is observed. In the last synthetic test, we show that the electrical conductivity field required to invert the self‐potential data can be determined with enough accuracy using an electrical resistivity tomography survey using the same electrodes configuration as used for the self‐potential investigation.
Demand Response at Distribution Grids: Exploiting Flexible Power Electronics Interfaces
Authors: Taylor Zach , Mohsenian‐Rad Hamed , Davoudi Ali 
Published: August 2016

AbstractWe explore the unique opportunities and challenges that arise in developing demand response programs that are intended for power distribution systems. The key is to understand the characteristics of the underlying physical power system, such as whether the distribution system is of type AC or DC. The role of power electronics interfaces are of particular interest in this context. Looking at controllability as a resource for power electronics interfaces, new design potentials are explored and case studies are presented to achieve optimal demand response operation in power distribution systems.
The Socio‐Economics of the Smart Grid – An Introduction
Authors: Pollitt Michael G. 
Published: August 2016

Abstract
This chapter aims to discuss the main socio‐economic issues raised by smart grid developments, drawing on the subsequent chapters in this section. These start with cyber‐security and privacy concerns. The economic benefits of smart grids are examined, focussing on business‐to‐business transactions within the electricity system, the system benefits of dynamic pricing, and the behavioural change opportunities of smart meters. We go on to introduce possible developments in the design of future markets made possible by increased transaction resolution. We then consider possible changes to the future organisation of the electricity distribution sector and the implications of increased smartness for electricity regulation.
Smart Grid Interoperability Standards
Authors: Gunther Erich W. 
Published: August 2016

Abstract
The Smart Grid must necessarily integrate numerous systems and devices that have historically operated autonomously and in silos of automation. These systems and devices generally come from multiple vendors and are deployed independently over long periods of time. The integration of these siloed systems results in a larger system that is more capable than the individual parts. Cost effective, maintainable, and secure integration of these systems requires identifying points of interoperability between these devices and systems where the rules of information exchange are well defined. The rules at the well‐defined points of interoperability are governed by Smart Grid interoperability standards. This chapter explores what is meant by a standard and how that term is often loosely applied to refer to a wide range of interoperability agreements.
Load Modeling
Authors: Terzija Vladimir , Regulski Pawel 
Published: August 2016

Abstract
Load modeling is an important aspect of power system studies and simulations and its role will become even more critical in future smart grids. This chapter summarizes some of the main opportunities and challenges of load modeling in the context of modern power systems and smart grids. Traditional static and dynamic load models are presented as well as power electronics load models to account for harmonic emission of loads. Deterministic and evolutionary computation methods for load model parameters identification are explained and online load modeling with the use of phasor measurement units is presented. The chapter also provides an introduction to the identification of active distribution network equivalents with the use of black box and gray box models. Such equivalents will become crucial in efficient power system simulations. Finally, the chapter discusses the potential of remote load control achieved through local voltage control. This mechanism may play an important role in helping to integrate the highly variable and often unpredictable intermittent renewable generation.
Dynamic‐State Estimation
Authors: Abur Ali 
Published: August 2016

AbstractStatic state estimators have been in use in control centres for over four decades now. Recent availability of synchronized phasor measurements for bus voltages and line currents allows development of dynamic state estimators which can track the frequency and synchronous machine state variables and complement the information provided by static state estimators on the network states. This chapter provides a brief overview of the static state estimation problem followed by an introduction to dynamic state estimation. The problem of dynamic state estimation is formulated and a dynamic state estimator whose implementation lends itself to large size power grids is described. The chapter also contains a discussion of observability analysis for dynamic state estimators which presents additional challenges due to the time varying and nonlinear nature of the system and measurement equations.
FACTS
,
HVDC
, and Supergrid
Authors: Wang Fred , Li Yalong , Shi Xiaojie 
Published: August 2016

Abstract
This chapter presents an overview of flexible AC transmission systems (FACTS), high‐voltage DC (HVDC) transmission, and the supergrid concept. All these technologies and concepts are based on power electronics. Their basic working principles, technology status and limitations, benefits, and applications in electric power grids are introduced. Some of the recent developments including distributed FACTS, partial FACTS, hybrid AC/DC, and DC grids are also discussed.
Grid Monitoring and State Estimation
Authors: McDermott Thomas E. 
Published: August 2016

AbstractState estimation is a “big data” enabler for any number of “smart grid” applications on the distribution system; these include reactive power management, outage management, loss reduction, demand response, adaptable overcurrent protection, condition‐based maintenance, distributed generation dispatch, integration with transmission system operations, and more. While fully developed on transmission systems, it has been more difficult to apply on distribution because there are not enough redundant sensors and communication capability. Algorithmic developments are also needed. When fully enabled, even more applications are likely to arise. The potential future use of microgrids would increase the value and opportunity for state estimation. In order to enable the full value of state estimation, the requirements and use cases need to be included up front in planning smart grid projects. Otherwise, post‐deployment sensor and communication channel upgrades are likely to be prohibitively expensive. Research continues to develop algorithms and software suited to the special problems of distribution system state estimation, but these are readily deployed when they become available. The real expense lies in the sensor and communication hardware.
Multimetal‐Substituted Epsilon‐Iron Oxide ϵ‐Ga0.31Ti0.05Co0.05Fe1.59O3 for Next‐Generation Magnetic Recording Tape in the Big‐Data Era
Authors: Ohkoshi Shin‐ichi , Namai Asuka , Yoshikiyo Marie , Imoto Kenta , Tamazaki Kazunori , Matsuno Koji , Inoue Osamu , Ide Tsutomu , Masada Kenji , Goto Masahiro , Goto Takashi , Yoshida Takayuki , Miyazaki Tatsuro 
Published: August 2016

AbstractFrom the viewpoints of large capacity, long‐term guarantee, and low cost, interest in magnetic recording tapes has undergone a revival as an archive storage media for big data. Herein, we prepared a new series of metal‐substituted ϵ‐Fe2O3, ϵ‐GaIII0.31TiIV0.05CoII0.05FeIII1.59O3, nanoparticles with an average size of 18 nm. Ga, Ti, and Co cations tune the magnetic properties of ϵ‐Fe2O3 to the specifications demanded for a magnetic recording tape. The coercive field was tuned to 2.7 kOe by introduction of single‐ion anisotropy on CoII (S=3/2) along the c‐axis. The saturation magnetization was increased by 44 % with GaIII (S=0) and TiIV (S=0) substitution through the enhancement of positive sublattice magnetizations. The magnetic tape media was fabricated using an actual production line and showed a very sharp signal response and a remarkably high signal‐to‐noise ratio compared to the currently used magnetic tape.
Bis(difluoromethyl)trimethylsilicate Anion: A Key Intermediate in Nucleophilic Difluoromethylation of Enolizable Ketones with Me3SiCF2H
Authors: Chen Dingben , Ni Chuanfa , Zhao Yanchuan , Cai Xian , Li Xinjin , Xiao Pan , Hu Jinbo 
Published: August 2016

AbstractA pentacoordinate bis(difluoromethyl)silicate anion, [Me3Si(CF2H)2]−, is observed for the first time by the activation of Me3SiCF2H with a nucleophilic alkali‐metal salt and 18‐crown‐6. Further study on its reactivity by tuning the countercation effect led to the discovery and development of an efficient, catalytic nucleophilic difluoromethylation of enolizable ketones with Me3SiCF2H by using a combination of CsF and 18‐crown‐6 as the initiation system. Mechanistic investigations demonstrate that [(18‐crown‐6)Cs]+[Me3Si(CF2H)2]− is a key intermediate in this catalytic reaction.
Reciprocal Self‐Assembly of Peptide–DNA Conjugates into a Programmable Sub‐10‐nm Supramolecular Deoxyribonucleoprotein
Authors: Kye Mahnseok , Lim Yong‐beom 
Published: August 2016

AbstractTo overcome the limitations of molecular assemblies, the development of novel supramolecular building blocks and self‐assembly modes is essential to create more sophisticated, complex, and controllable aggregates. The self‐assembly of peptide–DNA conjugates (PDCs), in which two orthogonal self‐assembly modes, that is, β‐sheet formation and Watson–Crick base pairing, are covalently combined in one supramolecular system, is reported. Despite extensive research, most self‐assembly studies have focused on using only one type of building block, which restricts structural and functional diversity compared to multicomponent systems. Multicomponent systems, however, suffer from poor control of self‐assembly behaviors. Covalently conjugated PDC building blocks are shown to assemble into well‐defined and controllable nanostructures. This controllability likely results from the decrease in entropy associated with the restriction of the molecular degrees of freedom by the covalent constraints. Using this strategy, the possibility to thermodynamically program nano‐assemblies to exert gene regulation activity with low cytotoxicity is demonstrated.
Paper‐Origami‐Based Multiplexed Malaria Diagnostics from Whole Blood
Authors: Xu Gaolian , Nolder Debbie , Reboud Julien , Oguike Mary C. , van Schalkwyk Donelly A. , Sutherland Colin J. , Cooper Jonathan M. 
Published: August 2016

AbstractWe demonstrate, for the first time, the multiplexed determination of microbial species from whole blood using the paper‐folding technique of origami to enable the sequential steps of DNA extraction, loop‐mediated isothermal amplification (LAMP), and array‐based fluorescence detection. A low‐cost handheld flashlight reveals the presence of the final DNA amplicon to the naked eye, providing a “sample‐to‐answer” diagnosis from a finger‐prick volume of human blood, within 45 min, with minimal user intervention. To demonstrate the method, we showed the identification of three species of Plasmodium, analyzing 80 patient samples benchmarked against the gold‐standard polymerase chain reaction (PCR) assay in an operator‐blinded study. We also show that the test retains its diagnostic accuracy when using stored or fixed reference samples.
Event‐Based Semiglobal Consensus of Homogenous Linear Multi‐Agent Systems Subject to Input Saturation
Authors: Zhou Bo , Liao Xiaofeng , Huang Tingwen , Li Huaqing , Chen Guo 
Published: August 2016

AbstractIn this paper, we consider the semiglobal leader‐following consensus of general linear multi‐agent systems subject to input saturation. First, an event‐triggered control protocol is provided to ensure semiglobal consensus of the multi‐agent systems, in which the agents should continuously monitor the information of their neighbors. Second, a self‐triggered control protocol is proposed to guarantee the semiglobal consensus of the multi‐agent systems, in which the agents only have access to the information of their neighbors in discrete time instants. Moreover, both event‐triggered control protocol and self‐triggered control protocol are proved to be Zeno‐free, that is, the inter‐event times for such two protocols have positive lower bounds. Finally, two numerical examples are provided to illustrate the effectiveness of the proposed event‐based semiglobal consensus protocols.
Cloning and characterization of novel cyclotides genes from South American plants
Authors: Cunha Nicolau Brito da , Barbosa Aulus Estevão Anjos de Deus , de Almeida Renato Goulart , Porto William Farias , Maximiano Mariana Rocha , Álvares Luana Cristina Silva , Munhoz Cassia Beatriz Rodrigues , Eugênio Chesterton Ulysses Orlando , Viana Antônio Américo Barbosa , Franco Octavio Luiz , Dias Simoni Campos 
Published: August 2016

AbstractCyclotides are multifunctional plant cyclic peptides containing 28‐37 amino acid residues and a pattern of three disulfide bridges, forming a motif known as the cyclic cystine knot. Due to their high biotechnological potential, the sequencing and characterization of cyclotide genes are crucial not only for cloning and establishing heterologous expression strategies, but also to understand local plant evolution in the context of host‐pathogen relationships. Here, two species from the Brazilian Cerrado, Palicourea rigida (Rubiaceae) and Pombalia lanata (A.St.‐Hil.) Paula‐Souza (Violaceae), were used for cloning and characterizing novel cyclotide genes. Using 3′ and 5′ RACE PCR and sequencing, two full cDNAs, named parigidin‐br2 (P. rigida) and hyla‐br1 (P. lanata), were isolated and shown to have similar genetic structures to other cyclotides. Both contained the conserved ER‐signal domain, N‐terminal prodomain, mature cyclotide domain and a C‐terminal region. Genomic sequencing of parigidin‐br2 revealed two different gene copies: one intronless allele and one presenting a rare 131‐bp intron. In contrast, genomic sequencing of hyla‐br1 revealed an intronless gene—a common characteristic of members of the Violaceae family. Parigidin‐br2 5′ and 3′ UTRs showed the presence of 12 putative candidate sites for binding of regulatory proteins, suggesting that the flanking and intronic regions of the parigidin‐br2 gene must play important roles in transcriptional rates and in the regulation of temporal and spatial gene expression. The high degree of genetic similarity and structural organization among the cyclotide genes isolated in the present study from the Brazilian Cerrado and other well‐characterized plant cyclotides may contribute to a better understanding of cyclotide evolution.
Highly Active Carbon/α‐MnO2 Hybrid Oxygen Reduction Reaction Electrocatalysts
Authors: Chen Gao , Sunarso Jaka , Zhu Yanping , Yu Jie , Zhong Yijun , Zhou Wei , Shao Zongping 
Published: August 2016

AbstractManganese oxides are attractive catalyst candidates for the oxygen reduction reaction (ORR) given their natural abundance and low toxicity. α‐MnO2, in particular, exhibits high ORR activity in an alkaline medium. The hybrid concept provides a way to obtain enhanced ORR performance and long‐term durability through an optimized metal oxide–support interaction. Herein, we synthesized a carbon nanotube (CNT)–graphene–α‐MnO2 hybrid in a hydrothermal reaction in which the MnO2 nanosheets were deposited on the interior and exterior surfaces of the CNT channels. The resultant hybrid displayed very high ORR activity that is only marginally less than the performance of a commercial 20 wt % Pt/C catalyst and showed even better stability. The excellent ORR activity was attributed to two main factors, that is, the mesoporous architecture of the catalyst and the strong electron coupling between the encapsulated metal oxide and the support. We also showed that the preferential deposition of MnO2 nanosheets within the CNT channels provides enhanced ORR performance relative to deposition on the exterior surfaces of the channels only. This in turn demonstrates unequivocally the confinement effect that the CNT exerts on the encapsulated metal oxide component, which can be exploited as a route to enhanced ORR activity.
Photoluminescence in Carborane–Stilbene Triads: A Structural, Spectroscopic, and Computational Study
Authors: Cabrera‐González Justo , Viñas Clara , Haukka Matti , Bhattacharyya Santanu , Gierschner Johannes , Núñez Rosario 
Published: August 2016

AbstractA set of triads in which o‐ and m‐carborane clusters are bonded to two stilbene units through Ccluster−CH2 bonds was synthesized, and their structures were confirmed by X‐ray diffraction. A study on the influence of the o‐ and m‐ isomers on the absorption and photoluminescence properties of the stilbene units in solution revealed no charge‐transfer contributions in the lowest excited state, as confirmed by (TD)DFT calculations. The presence of one or two B−I groups in m‐carborane derivatives does not affect the emission properties of the stilbenes in solution, probably due to the rather large distance between the iodo substituents and the fluorophore. Nevertheless, a significant redshift of the photoluminescence (PL) emission maximum in the solid state (thin films and powder samples) compared to solution was observed; this can be traced back to PL sensitization, most probably due to more densely packed stilbene moieties. Remarkably, the PL absolute quantum yields of powder samples are significantly higher than those in solution, and this was attributed to the restricted environment and the aforementioned sensitization. Thus, the bonding of the carborane clusters to two stilbene units preserves their PL behavior in solution, but produces significant changes in the solid state. Furthermore, iodinated species can be considered to be promising precursors for theranostic agents in which both imaging and therapeutic functions could possibly be combined.
Effect of Inter‐Porphyrin Distance on Spin‐State in Diiron(III) μ‐Hydroxo Bisporphyrins
Authors: Sil Debangsu , Khan Firoz Shah Tuglak , Rath Sankar Prasad 
Published: August 2016

AbstractThe synthesis, structure, and properties of bischloro, μ‐oxo, and a family of μ‐hydroxo complexes (with BF4−, SbF6−, and PF6− counteranions) of diethylpyrrole‐bridged diiron(III) bisporphyrins are reported. Spectroscopic characterization has revealed that the iron centers of the bischloro and μ‐oxo complexes are in the high‐spin state (S=5/2). However, the two iron centers in the diiron(III) μ‐hydroxo complexes are equivalent with high spin (S=5/2) in the solid state and an intermediate‐spin state (S=3/2) in solution. The molecules have been compared with previously known diiron(III) μ‐hydroxo complexes of ethane‐bridged bisporphyrin, in which two different spin states of iron were stabilized under the influence of counteranions. The dimanganese(III) analogues were also synthesized and spectroscopically characterized. A comparison of the X‐ray structural parameters between diethylpyrrole and ethane‐bridged μ‐hydroxo bisporphyrins suggest an increased separation, and hence, less interactions between the two heme units of the former. As a result, unlike the ethane‐bridged μ‐hydroxo complex, both iron centers become equivalent in the diethylpyrrole‐bridged complex and their spin state remains unresponsive to the change in counteranion. The iron(III) centers of the diethylpyrrole‐bridged diiron(III) μ‐oxo bisporphyrin undergo very strong antiferromagnetic interactions (J=−137.7 cm−1), although the coupling constant is reduced to only a weak value in the μ‐hydroxo complexes (J=−42.2, −44.1, and −42.4 cm−1 for the BF4, SbF6, and PF6 complexes, respectively).