bluuebunny/crossref_metadata_2025 huggingface dataset:
Microarrays
Authors: Taylor Richard F.
Published: June 2016

Microarrays are analytical devices that utilize a platform technology for the performance of hundreds to thousands of individual reactions or assays simultaneously. These include nucleic‐acid probe/enzyme and immunoassays for the detection and analysis of DNA, RNA, proteins, polysaccharides, and lipids and to study the interactions of biomolecules with drugs and other bioactive agents. The basic components of a microarray are the substrate, active layer containing receptors, and the detection probe. Microarrays can be characterized using a number of parameters. These include density, regularity, and receptor purity and reactivity. Fabrication methods are detailed and included information on the various substrates used and substrate activation, array spotting, andin situsynthesis. Applications discussed in detail include genomic analysis, expression analysis, and diagnostics.
The effects of dynamics on the triboelectrification of volcanic ash
Authors: Méndez Harper Joshua , Dufek Josef
Published: June 2016

Lightning is often observed during explosive volcanic eruptions, and the charging processes associated with these displays have been attributed to several mechanisms. In this work we delineate a set of experiments designed to quantify silicate‐based triboelectric charging in the volcanic context. Using natural samples from three different volcanoes, we show that the rate of triboelectrification in a fluidized bed depends on the energy input into the granular system. Experiments are conducted employing nonintrusive electrostatic sensors, ensuring that all charge exchange arises solely from particle‐particle collisions. At higher fluidization energies, particles undergo more frequent and energetic collisions, facilitating the transfer of charge. This finding implies that triboelectric charging could help promote charging in regions of the eruptive system that contain numerous particle‐particle collisions such as the conduit and gas thrust regions. Our experiments also suggest that surface charge density is capped, at least in part, by atmospheric conditions, specifically the breakdown characteristics of the gas.
A coupled force‐restore model of surface temperature and soil moisture using the maximum entropy production model of heat fluxes
Authors: Huang S.‐Y. , Wang J.
Published: June 2016

A coupled force‐restore model of surface soil temperature and moisture (FRMEP) is formulated by incorporating the maximum entropy production model of surface heat fluxes and including the gravitational drainage term. The FRMEP model driven by surface net radiation and precipitation are independent of near‐surface atmospheric variables with reduced sensitivity to the uncertainties of model input and parameters compared to the classical force‐restore models (FRM). The FRMEP model was evaluated using observations from two field experiments with contrasting soil moisture conditions. The modeling errors of the FRMEP predicted surface temperature and soil moisture are lower than those of the classical FRMs forced by observed or bulk formula based surface heat fluxes (bias 1 ~ 2°C versus ~4°C, 0.02 m3 m−3 versus 0.05 m3 m−3). The diurnal variations of surface temperature, soil moisture, and surface heat fluxes are well captured by the FRMEP model measured by the high correlations between the model predictions and observations (r ≥ 0.84). Our analysis suggests that the drainage term cannot be neglected under wet soil condition. A 1 year simulation indicates that the FRMEP model captures the seasonal variation of surface temperature and soil moisture with bias less than 2°C and 0.01 m3 m−3 and correlation coefficients of 0.93 and 0.9 with observations, respectively.
What effect do substorms have on the content of the radiation belts?
Authors: Forsyth C. , Rae I. J. , Murphy K. R. , Freeman M. P. , Huang C.‐L. , Spence H. E. , Boyd A. J. , Coxon J. C. , Jackman C. M. , Kalmoni N. M. E. , Watt C. E. J.
Published: June 2016

Substorms are fundamental and dynamic processes in the magnetosphere, converting captured solar wind magnetic energy into plasma energy. These substorms have been suggested to be a key driver of energetic electron enhancements in the outer radiation belts. Substorms inject a keV “seed” population into the inner magnetosphere which is subsequently energized through wave‐particle interactions up to relativistic energies; however, the extent to which substorms enhance the radiation belts, either directly or indirectly, has never before been quantified. In this study, we examine increases and decreases in the total radiation belt electron content (TRBEC) following substorms and geomagnetically quiet intervals. Our results show that the radiation belts are inherently lossy, shown by a negative median change in TRBEC at all intervals following substorms and quiet intervals. However, there are up to 3 times as many increases in TRBEC following substorm intervals. There is a lag of 1–3 days between the substorm or quiet intervals and their greatest effect on radiation belt content, shown in the difference between the occurrence of increases and losses in TRBEC following substorms and quiet intervals, the mean change in TRBEC following substorms or quiet intervals, and the cross correlation between SuperMAG AL (SML) and TRBEC. However, there is a statistically significant effect on the occurrence of increases and decreases in TRBEC up to a lag of 6 days. Increases in radiation belt content show a significant correlation with SML and SYM‐H, but decreases in the radiation belt show no apparent link with magnetospheric activity levels.
Induced earthquake magnitudes are as large as (statistically) expected
Authors: van der Elst Nicholas J. , Page Morgan T. , Weiser Deborah A. , Goebel Thomas H.W. , Hosseini S. Mehran
Published: June 2016

A major question for the hazard posed by injection‐induced seismicity is how large induced earthquakes can be. Are their maximum magnitudes determined by injection parameters or by tectonics? Deterministic limits on induced earthquake magnitudes have been proposed based on the size of the reservoir or the volume of fluid injected. However, if induced earthquakes occur on tectonic faults oriented favorably with respect to the tectonic stress field, then they may be limited only by the regional tectonics and connectivity of the fault network. In this study, we show that the largest magnitudes observed at fluid injection sites are consistent with the sampling statistics of the Gutenberg‐Richter distribution for tectonic earthquakes, assuming no upper magnitude bound. The data pass three specific tests: (1) the largest observed earthquake at each site scales with the log of the total number of induced earthquakes, (2) the order of occurrence of the largest event is random within the induced sequence, and (3) the injected volume controls the total number of earthquakes rather than the total seismic moment. All three tests point to an injection control on earthquake nucleation but a tectonic control on earthquake magnitude. Given that the largest observed earthquakes are exactly as large as expected from the sampling statistics, we should not conclude that these are the largest earthquakes possible. Instead, the results imply that induced earthquake magnitudes should be treated with the same maximum magnitude bound that is currently used to treat seismic hazard from tectonic earthquakes.
Kuroshio subsurface water feeds the wintertime Taiwan Warm Current on the inner East China Sea shelf
Authors: Lian Ergang , Yang Shouye , Wu Hui , Yang Chengfan , Li Chao , Liu James T.
Published: June 2016

The Taiwan Warm Current (TWC) has an overwhelming influence on the heat, salt, and nutrients balance on one of the broadest shelf in the world, the East China Sea shelf. In winter, the TWC flows in an unusual upwind direction and reaches the Changjiang (Yangtze River) Estuary, but its origin and pathway are intensely debated. Here combined evidences from current measurement, hydrographic, and stable isotopic data all suggest that the wintertime TWC intrusion off the Changjiang Estuary mainly originates from the Kuroshio subsurface water northeast of Taiwan, rather than from the Taiwan Strait warm water. The Kuroshio‐branched water northeast of Taiwan can intrude into the inner shelf near the Zhe‐Min Coast via bottom layer, manifesting by a pronounced boundary at 50 m isobath around 28°N, and thereby feeds the TWC intrusion into the Changjiang Estuary. The intrusion complicates the hydrological process in the estuary and shelf sea, and its impact on marine environment deserves more research attentions.
Albedo climatology for European land surfaces retrieved from AVHRR data (1990–2014) and its spatial and temporal analysis from green‐up to vegetation senescence
Authors: Sütterlin M. , Stöckli R. , Schaaf C. B. , Wunderle S.
Published: June 2016

Satellite‐based, long‐term records of surface albedo characterization that accurately capture spatial and temporal patterns are essential to develop climate models and to monitor the impact of land use changes on the terrestrial energy and water balance. This study presents the first Bidirectional Reflectance Distribution Function (BRDF) and albedo data set derived from the Advanced Very High Resolution Radiometer (AVHRR) Local Area Coverage reflectance data acquired on board National Oceanic and Atmospheric Administration and Meteorological Operational platforms from 1990 to 2014 over Europe. The objectives of this paper are to describe the data set's surface albedo climatology and anomalies in the visible, near‐infrared, and shortwave broadbands for the growing season months of May to September in order to facilitate utilization of the data by the climate modeling communities. The results demonstrate that the AVHRR BRDF and albedo data have temporal and spatial patterns that are appropriate for the underlying predominant land cover type and accurately reflect the associated climate variation. Visible and near‐infrared broadband albedo anomalies are found to be contrasting in most years, and their spatial distributions depict responses of vegetation to climate events (e.g., heat waves). Visible albedo of crops and near‐infrared albedo of pastures show a higher interannual variation than respective albedos of other snow‐free land covers, while the interannual standard deviations are found to be lower than 0.015. Our findings indicate the importance of taking into account the spectrally distinct variability of surface albedo when analyzing its complex spatiotemporal dynamics in climate‐related research.
Semantic wireless localization of WiFi terminals in smart buildings
Authors: Ahmadi H. , Polo A. , Moriyama T. , Salucci M. , Viani F.
Published: June 2016

The wireless localization of mobile terminals in indoor scenarios by means of a semantic interpretation of the environment is addressed in this work. A training‐less approach based on the real‐time calibration of a simple path loss model is proposed which combines (i) the received signal strength information measured by the wireless terminal and (ii) the topological features of the localization domain. A customized evolutionary optimization technique has been designed to estimate the optimal target position that fits the complex wireless indoor propagation and the semantic target‐environment relation, as well. The proposed approach is experimentally validated in a real building area where the available WiFi network is opportunistically exploited for data collection. The presented results point out a reduction of the localization error obtained with the introduction of a very simple semantic interpretation of the considered scenario.
SiGe BiCMOS balanced transmission line based on coplanar waveguide and split ring resonator
Authors: Serrano Enrique , Borja Alejandro L. , Boccia Luigi , Cascon Joaquin , Ibrahim Safwat , Calzona D. , Amendola G.
Published: June 2016

In this work, the design of a right‐/left‐handed composite transmission line implementation with passband characteristics is demonstrated on 0.13 µm silicon‐germanium bipolar CMOS (SiGe BiCMOS) technology. The proposed structure is formed by a shorted coplanar waveguide transmission line loaded with split ring resonators (SRRs). As it will be shown, by controlling the geometry of the SRRs as well as their electric coupling with the host line, it is possible to achieve a balanced passband response with widespread bandwidth at millimeter wave frequencies. Besides, this paper introduces a configuration that allows to significantly lower the resonant frequency of the SRRs by loading the rings with Metal‐Insulator‐Metal capacitors. It will be illustrated how this approach allows to reduce the center band frequency of about 40% preserving the balanced behavior and without increasing the resonator size. Finally, the proposed design was experimentally validated with a prototype exhibiting an extended passband with a fractional bandwidth of 19.3% and −3.2 dB of insertion loss around the central frequency of 60 GHz. The use of these transmission lines can be foreseeing in high‐capacity millimeter wave communication systems which require compact passband blocks integrated on chip.
Assessment of extreme values in geomagnetic and geoelectric field variations for Canada
Authors: Nikitina L. , Trichtchenko L. , Boteler D. H.
Published: June 2016

Disturbances of the geomagnetic field produced by space weather events can have an impact on power systems and other critical infrastructure. To mitigate these risks it is important to determine the extreme values of geomagnetic activity that can occur. More than 40 years of 1 min magnetic data recorded at 13 Canadian geomagnetic observatories have been analyzed to evaluate extreme levels in geomagnetic and geoelectric activities in different locations of Canada. The hourly ranges of geomagnetic field variations and hourly maximum in rate of change of the magnetic variations have been used as measures of geomagnetic activity. Geoelectric activity is estimated by the hourly peak amplitude of the geoelectric fields calculated with the use of Earth resistivity models specified for different locations in Canada. A generalized extreme value distribution was applied to geomagnetic and geoelectric indices to evaluate extreme geomagnetic and geoelectric disturbances, which could happen once per 50 and once per 100 years with 99% confidence interval. Influence of geomagnetic latitude and Earth resistivity models on the results for the extreme geomagnetic and geoelectric activity is discussed. The extreme values provide criteria for assessing the vulnerability of power systems and other technology to geomagnetic activity for design or mitigation purposes.
High‐Performance Liquid Chromatography–Mass Spectrometry in Peptide and Protein Analysis
Authors: Shen Tun‐Li
Published: June 2016

High‐performance liquid chromatography/mass spectrometry (HPLC/MS) is one of the most powerful tools in peptide and protein analysis today. Complementary to HPLC/MS, capillary electrophoresis/mass spectrometry (CE/MS) is another highly efficient separation technique that can be coupled directly with MS using electrospray ionization (ESI), and the technique has proved to be very sensitive. The popularity of HPLC/MS has resulted from the developments in both chromatography and MS. The advances in soft ionization, in particular MALDI6 and ESI, have not only broadened the range of biomolecules that can be analyzed but also provided unprecedented sensitivity. Parallel to the development of MS, the utilization of capillary to nano HPLC column technology in conjunction with electrospray ionization mass spectrometry (ESIMS) has further extended the detection limits. HPLC/MS has been applied in many areas of peptide and protein study. For peptide analysis, this method has proved to be useful from the routine screening of synthetic peptide products to the study of naturally occurring peptides at the femtomole level. One of the major contributions HPLC/MS had made in protein analysis is in the characterization of protein posttranslational modifications. Notable examples are the analysis of phosphoproteins and glycoproteins, primarily using the technique of monitoring diagnostic marker ions. As a result of genome projects in the 1990s, there is an increasing need to develop analytical tools for proteomics research. The combination of database search, multidimensional HPLC, and tandem mass spectrometry (MS/MS) has become an ideal format for large‐scale high‐throughput automatic identification of proteomics analysis. Many biological problems increasingly require quantification of proteins. The combination of chromatography and MS/MS has become highly successful for absolute quantitative analysis of proteins, from analyzing recombinant proteins to global protein analysis.
Nuclear Magnetic Resonance and Electron Spin Resonance Spectroscopy: Introduction
Authors: Dybowski Cecil
Published: June 2016

A brief introduction to the phenomenon of magnetic resonance provides a gateway to other, more advanced discussions of the topics related to this important analytical technology.
Nuclear Magnetic Resonance Instrumentation
Authors: Bai Shi
Published: June 2016

The nuclear magnetic resonance (NMR) spectrometer consists of a superconducting magnet, a sample probe, a radio frequency (RF) transmitter, a receiver, and a computer for instrument control and data processing. The superconducting magnet provides an ultrastable magnetic field in the central volume of the magnet. To maintain the current, the solenoid that produces the field is immersed in liquid helium to maintain the superconducting state. Surrounding the magnet volume is a set of vacuum jackets and a liquid nitrogen‐filled volume to isolate the low‐temperature regions from room temperature. The magnet has a bore to house the sample probe and a room‐temperature shim (RTS) coil assembly to reduce inhomogeneity of the magnetic field across the active sample volume. The NMR sample can be in liquid, solid, or gas phases. RF pulses, from one or a set of high‐power transmitters, are applied to the sample through the RF coil that surrounds the active sample area to perturb the sample. The RF pulses are controlled to ensure precise frequency, phase, duration, and amplitude of the RF voltage. The response of the sample is gathered by recording the induced voltage across the RF coil. The signal is digitized as a so‐called free induction decay (FID) with a high‐performance RF receiver including a preamplifier, an amplifier, and an analog‐to‐digital converter (ADC). Using Fourier transformation (FT), the time domain FID is converted into the frequency‐domain spectrum, often known as the NMR spectrum.
Selective Nanoparticles in Microextraction
Authors: Ríos‐Gómez Julia , Lasarte‐Aragonés Guillermo , Cárdenas Soledad , Lucena Rafael
Published: June 2016

Sorption capacity is a critical issue in microextraction techniques where the amount of sorbent is reduced to the low milligram range and even lower. In this context, the use of sorbents with a high superficial area is really desirable. Nanoparticles (NPs) fulfill this main requirement while, at the same time, provide the analyst with a wide variety of interaction chemistries that can be easily selected depending on the analytical problem under study. In addition, certain NPs present especial properties (e.g. superparamagnetism) that make them so attractive in the microextraction context. Focusing on sorption capacity is meaningless when complex samples, the usual situation in Bioanalysis, are processed as matrix components may overload the sorbent avoiding the extraction of the target analytes. In this scenario, selectivity then becomes a critical variable of concern. This article discusses the role of selectivity in microextraction and provides a general overview of the main coatings used to boost the selectivity of NPs. In particular, this article describes the use of two groups of coatings as selectivity enhancers. On the one hand, the use of synthetic polymers including molecularly imprinted polymers (MIPs) and restricted access materials (RAMs) is a well‐established alternative in analytical sciences. On the other hand, biopolymers, such as antibodies and aptamers, exploit biorecognition that is by far the most selective interaction. Both alternatives are described in detail in this article.
Electrophoretic Approaches for LogPDetermination of Small Molecules and Polymers
Authors: Leclercq Laurent , Jin Xiaoyun , Cottet Hervé
Published: June 2016

Hydrophobicity is generally related to the determination of logPvalue, which is a key parameter in the structure/activity relationship, especially in pharmaceutical and biomedical fields. The aim of this article is to focus on the capillary electrophoresis (CE)‐related techniques for the logP(or logDfor ionizable compounds) determination of small molecules and polymers. These techniques include micellar electrokinetic chromatography (MEKC), microemulsion electrokinetic chromatography (MEEKC), liposome electrokinetic chromatography (LEKC), and vesicle electrokinetic chromatography (VEKC). Comparison is made based on several parameters, such as surfactants chemical nature or composition and pH of the analysis buffer. Characterization of polymer hydrophobicity is a challenging issue because polymeric analytes (and especially polyelectrolytes) tend very often to remain at the water/organic phase interface making the classical shake‐flask method difficult to apply. In addition, polymers present distributions of composition and molar masses generating hydrophobicity distribution that should be characterized beyond the determination of average logP(or logD) values. Recently, determination of polymer logDdistribution has been addressed and was reviewed in detail in the case of polycationic gene delivery vectors.
Die Design Modification to Improve Workability during Equal Channel Angular Pressing
Authors: Torabi Mohsen , Eivani Ali Reza , Jafarian Hamidreza , Salehi Mohammad Taghi
Published: June 2016

The effect of choked and relieved configurations of die exit channel on the workability of AA6063 alloy during equal channel angular pressing (ECAP) is investigated. Finite element simulation is used to predict variation in maximum principal stress (σ1) to be consequently correlated to the occurrence of surface cracking. Critical regions for fracture are found at the top surface of the sample at which tensile σ1 exists. Tensile stresses are involved when dies with parallel or relieved exit channels are used while the stresses are compressive in case of die with choked exit channel. Choke angle of 0.2° is found as the optimum value guaranteeing compressive σ1 in addition to avoiding significant increase in strain inhomogeneity and pressing pressure.
A Review of SiC Fiber Oxidation with a New Study of Hi‐Nicalon SiC Fiber Oxidation
Authors: Wilson Megan , Opila Elizabeth
Published: June 2016

The linear and parabolic oxidation rate constants and activation energies for SiC fibers available in the literature are reviewed for the first time. Oxidation experiments are also conducted with Hi‐Nicalon SiC fibers over 700–1 300 °C in dry O2 with thermogravimetric analysis. Linear oxidation kinetics are observed from 700 to 800 °C and parabolic kinetics are observed from 900 to 1 300 °C. The linear and parabolic oxidation rate constant activation energies are determined to be 83 and 108 kJ mol−1, respectively. These kinetic results are compared with the literature values. Differences in oxidation behavior are assessed as a function of fiber composition.
Nanoscale Engineering of Heterostructured Anode Materials for Boosting Lithium‐Ion Storage
Authors: Chen Gen , Yan Litao , Luo Hongmei , Guo Shaojun
Published: June 2016

Rechargeable lithium‐ion batteries (LIBs), as one of the most important electrochemical energy‐storage devices, currently provide the dominant power source for a range of devices, including portable electronic devices and electric vehicles, due to their high energy and power densities. The interest in exploring new electrode materials for LIBs has been drastically increasing due to the surging demands for clean energy. However, the challenging issues essential to the development of electrode materials are their low lithium capacity, poor rate ability, and low cycling stability, which strongly limit their practical applications. Recent remarkable advances in material science and nanotechnology enable rational design of heterostructured nanomaterials with optimized composition and fine nanostructure, providing new opportunities for enhancing electrochemical performance. Here, the progress as to how to design new types of heterostructured anode materials for enhancing LIBs is reviewed, in the terms of capacity, rate ability, and cycling stability: i) carbon‐nanomaterials‐supported heterostructured anode materials; ii) conducting‐polymer‐coated electrode materials; iii) inorganic transition‐metal compounds with core@shell structures; and iv) combined strategies to novel heterostructures. By applying different strategies, nanoscale heterostructured anode materials with reduced size, large surfaces area, enhanced electronic conductivity, structural stability, and fast electron and ion transport, are explored for boosting LIBs in terms of high capacity, long cycling lifespan, and high rate durability. Finally, the challenges and perspectives of future materials design for high‐performance LIB anodes are considered. The strategies discussed here not only provide promising electrode materials for energy storage, but also offer opportunities in being extended for making a variety of novel heterostructured nanomaterials for practical renewable energy applications.
Properties of a Thermotropic Nematic Liquid Crystal Doped with Graphene Oxide
Authors: Al‐Zangana Shakhawan , Iliut Maria , Turner Michael , Vijayaraghavan Aravind , Dierking Ingo
Published: June 2016

Graphene oxide (GO) nanoparticles of two different sizes are dispersed in the nematic liquid crystal (LC) 5CB covering a wide concentration range. The dielectric properties, as well as the electrooptic behavior, including threshold voltage, elastic constant, and response times are investigated as a function of GO concentration. It is found that small graphene oxide flakes of mean size of 560 nm are better and easier dispersible than larger flakes of 2.8 μm mean size. The nematic–isotropic transition only increases slightly for the (GO+LC) hybrid systems. For increasing GO concentrations the threshold voltage and splay elastic constant dramatically increase, until saturation for a concentration of ≈1% by weight GO. The field driven switching‐on time is practically independent of concentration, while the switching‐off time, which is purely elastically driven, exhibits a strongly decreasing behavior. Dielectric spectroscopy reveals a noncollective relaxation which is absent in the neat liquid crystal. This may be attributed to a drastically slowed down molecular relaxation related to the rotation around the short axis of the liquid crystal molecules. When heating the thermotropic liquid crystal into its isotropic phase, the latter acts as a solvent for the GO particles, and a lyotropic nematic phase with largely reduced birefringence is formed.
Oxidative Coupling of Enamines and Disulfides via Tetrabutylammonium Iodide/tert‐Butyl Hydroperoxide‐Mediated Intermolecular Oxidative C(sp2)S Bond Formation Under Transition Metal‐Free Conditions
Authors: Sun Jiyun , Zhang‐Negrerie Daisy , Du Yunfei
Published: June 2016

The reaction of enamine compounds with disulfides in the presence of tert‐butyl hydroperoxide and a catalytic amount of tetrabutylammonium iodide conveniently afforded a variety of α‐thioenamine compounds through the intermolecular oxidative C(sp2)S coupling. Incorporating both of the sulfide moieties in the disulfides into the final products under oxidative conditions, this novel approach exhibits the feature of atom efficiency. A radical mechanistic pathway for the reaction process has been proposed.

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Palladium‐Catalyzed α‐Arylation of Methyl Sulfonamides with Aryl Chlorides
Authors: Zheng Bing , Li Minyan , Gao Gui , He Yuying , Walsh Patrick J.
Published: June 2016

A palladium‐catalyzed α‐arylation of sulfonamides with aryl chlorides is presented. A Buchwald‐type pre‐catalyst formed with Kwong’s indole‐based ligand enabled this transformation to be compatible with a large variety of methyl sulfonamides and aryl chlorides in good to excellent yields. Importantly, under the optimized reaction conditions, only mono‐arylated products were observed. This method has been applied to the efficient synthesis of sumatriptan, which is used to treat migraines.

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Copper‐Catalyzed Addition of Alkylboranes to Iminoacetates: Access to α‐Alkyl Branched α‐Amino Acids
Authors: Xiao Xinsheng , Zhang Wei , Lu Xiaoxia , Deng Yuanfu , Jiang Huangfeng , Zeng Wei
Published: June 2016

A copper(I)‐catalyzed addition of alkylborane reagents to α‐iminoacetates has been developed to assemble both acyclic and cyclic α‐branched α‐amino carboxylic acid derivatives in good yields. A wide variety of unactivated alkenes are well tolerated in this transformation.

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Palladium‐Catalyzed Oxidative Carbonylation of Aromatic C−H Bonds with Alcohols using Molybdenum Hexacarbonyl as the Carbon Monoxide Source
Authors: Wang Zechao , Li Yahui , Zhu Fengxiang , Wu Xiao‐Feng
Published: June 2016

With molybdenum hexacarbonyl as the carbon monoxide source, a general palladium‐catalyzed carbonylative transformation of the C−H bond on aromatic rings to produce esters has been developed. Good yields of the corresponding products have been obtained with wide functional group tolerance and excellent regioselectivity. A variety of aliphatic alcohols are suitable reactants here.

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Combining Nature‐Inspired, Graphene‐Wrapped Flexible Electrodes with Nanocomposite Polymer Electrolyte for Asymmetric Capacitive Energy Storage
Authors: Tang Jiayong , Yuan Ping , Cai Chuanlin , Fu Yanbao , Ma Xiaohua
Published: June 2016

Two kinds of free‐standing electrodes, reduced graphene oxide (rGO)‐wrapped Fe‐doped MnO2 composite (G‐MFO) and rGO‐wrapped hierarchical porous carbon microspheres composite (G‐HPC) are fabricated using a frozen lake‐inspired, bubble‐assistance method. This configuration fully enables utilization of the synergistic effects from both components, endowing the materials to be excellent electrodes for flexible and lightweight electrochemical capacitors. Moreover, a nonaqueous HPC‐doped gel polymer electrolyte (GPE‐HPC) is employed to broad voltage window and improve heat resistance. A fabricated asymmetric supercapacitor based on G‐MFO cathode and G‐HPC anode with GPE‐HPC electrolyte achieves superior flexibility and reliability, enhanced energy/power density, and outstanding cycling stability. The ability to power light‐emitting diodes also indicates the feasibility for practical use. Therefore, it is believed that this novel design may hold great promise for future flexible electronic devices.
A controllability analysis of a pilot‐scale CO2 capture plant using ionic liquids
Authors: Valencia‐Marquez Darinel , Flores‐Tlacuahuac Antonio , Ricardez‐Sandoval Luis
Published: June 2016

Nowadays there is a world concern on the impact and effect of large CO2 atmospheric concentrations on human health. Fossil‐fuel combustion processes in power plants are among the major contributors to this issue. Hence, it becomes important to develop new clean and sustainable processes aimed to reduce the amount of CO2 released to atmosphere by combustion processes in power plants. One of the best feasible manners to achieve this purposes lies in the use of a closed‐loop control system able to keep the amount of green‐house gases under specification even in the presence of unexpected scenarios. Of course, CO2 capture has been extensively researched in the past. However, in this regard the industrial practice has consisted in using Amines leading to sustainability and safety issues. Hence, it makes sense to seek for new and potentially environmental friendly process design to address CO2 reduction from power plants but applying a new type of sustainable stripping solvents. In this work we address the sustainable CO2 reduction issue from a process control point of view applying a previous design proposed by our research team based on the deployment of Ionic Liquids (IL) as potential green solvents and developing an efficient and decentralized multiloop control system. We demonstrate that the closed‐loop system is able to maintain the CO2 concentration levels under specification by testing in presence of several demanding scenarios. Overall, from an economic, sustainable and control point of view it looks feasible to replace the traditional amines‐based CO2 capture process by other alternatives based on the application of IL as potential green solvents. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3298–3309, 2016
Integrated design of agricultural and industrial processes: A case study of combined sugar and ethanol production
Authors: Ouchida Kotaro , Fukushima Yasuhiro , Ohara Satoshi , Sugimoto Akira , Hirao Masahiko , Kikuchi Yasunori
Published: June 2016

Bioethanol production from molasses has advantages in greenhouse gas emissions because of its energy acquisition from bagasse. However, the improvement of bioethanol productivity is challenging; while each elemental technology option can be greatly improved, the trade‐offs between the production of raw sugar and bioethanol are complex. This issue should be addressed through the optimization of the whole system, including both agricultural and industrial processes. In this study, we constructed a model of combined raw sugar and bioethanol production from sugarcane considering agricultural and industrial technology options. Data were acquired through a detailed investigation of actual sugar mills. Case studies on the redesign of combined raw sugar and bioethanol production demonstrated that the simultaneous implementation of both technology options increases production of food, materials, and energy from plant‐derived renewable resources, thus demonstrating the effectiveness of the interdisciplinary approach. © 2016 American Institute of Chemical Engineers AIChE J, 63: 560–581, 2017
Tandem Prins Cyclization for the Stereoselective Synthesis of Bridged Benzopyran Derivatives
Authors: Subba Reddy Basi V. , Srivastava Nikhil , Begum Zubeda , Lakshmi Jerripothula K. , Sridhar Balasubramanian
Published: June 2016

A tandem bicyclization strategy has been developed for the stereoselective synthesis of 3,4‐dihydro‐2 H,6H‐2,6‐methanobenzo[b][1,5]dioxocine derivatives in good yields and selectivities through the cyclocondensation of 2‐(1‐hydroxy‐3‐methylbut‐3‐en‐1‐yl)phenol with various aldehydes by using 10 mol % BF3⋅OEt2. This is the first reported stereoselective construction of a bridged tricyclic skeleton through a cascade Prins cyclization procedure. This process constitutes an elegant strategy for the quick construction of tricyclic architectures in a single step.
Rh(II)‐Catalyzed Chemoselective Synthesis of 3‐Substituted Oxindoles by C(sp2)−H and C(sp2)−N Functionalization of β‐Enaminoesters
Authors: Yun Sang Hyeon , Xia Likai , Kim Sung Hong , Lee Yong Rok
Published: June 2016

A novel chemoselective synthesis of 3‐substituted oxindoles and 3‐substituted 3‐aminooxindoles starting from various 3‐diazoindolin‐2‐ones and β‐enaminoesters was developed through rhodium(II)‐catalyzed C(sp2)−H and C(sp2)−N functionalization. This protocol provides a rapid synthetic route to a diverse range of 3‐substituted oxindoles and 3‐substituted 3‐aminooxindoles with good yields. The chemoselectivity for the formation of the 3‐substituted oxindoles and 3‐substituted 3‐aminooxindoles was controlled by the substituents on the nitrogen atom of the β‐enaminoesters.
Die Steuerung des Stealth‐Effekts von Nanoträgern durch das Verständnis der Proteinkorona
Authors: Schöttler Susanne , Landfester Katharina , Mailänder Volker
Published: June 2016

In den letzten zehn Jahren haben polymere Nanoträger immer mehr Interesse und Verwendung in medizinischen Anwendungen gefunden. Besonders beim Einsatz als Wirkstoff‐Träger lassen sich mit Nanoträgern viele Hindernisse der medikamentösen Therapie überwinden. Ihre Anwendung wird jedoch durch die komplexe Zusammensetzung der Partikelabdeckung mit Blutproteinen (“Proteinkorona”) erschwert. Diese Proteinkorona macht Vorhersagen über die zelluläre Interaktion, Biodistribution und Toxizität nahezu unmöglich. Vor allem die unspezifische Aufnahme der Nanoträger ist ein wesentliches Hindernis bei der klinischen Anwendung. Dieser Kurzaufsatz gibt einen Überblick über unseren Kenntnisstand auf diesem Gebiet; der Fokus liegt dabei auf Oberflächenfunktionalisierungen, die die unspezifische Aufnahme reduzieren (“Stealth‐Effekt”). Erörtert werden auch Möglichkeiten zur weiteren Verbesserung von Nanoträgern.
Computer‐Aided Production of Scaffolded DNA Nanostructures from Flat Sheet Meshes
Authors: Benson Erik , Mohammed Abdulmelik , Bosco Alessandro , Teixeira Ana I. , Orponen Pekka , Högberg Björn
Published: June 2016

The use of DNA as a nanoscale construction material has been a rapidly developing field since the 1980s, in particular since the introduction of scaffolded DNA origami in 2006. Although software is available for DNA origami design, the user is generally limited to architectures where finding the scaffold path through the object is trivial. Herein, we demonstrate the automated conversion of arbitrary two‐dimensional sheets in the form of digital meshes into scaffolded DNA nanostructures. We investigate the properties of DNA meshes based on three different internal frameworks in standard folding buffer and physiological salt buffers. We then employ the triangulated internal framework and produce four 2D structures with complex outlines and internal features. We demonstrate that this highly automated technique is capable of producing complex DNA nanostructures that fold with high yield to their programmed configurations, covering around 70 % more surface area than classic origami flat sheets.
Integrin‐Targeting Knottin Peptide–Drug Conjugates Are Potent Inhibitors of Tumor Cell Proliferation
Authors: Cox Nick , Kintzing James R. , Smith Mark , Grant Gerald A. , Cochran Jennifer R.
Published: June 2016

Antibody–drug conjugates (ADCs) offer increased efficacy and reduced toxicity compared to systemic chemotherapy. Less attention has been paid to peptide–drug delivery, which has the potential for increased tumor penetration and facile synthesis. We report a knottin peptide–drug conjugate (KDC) and demonstrate that it can selectively deliver gemcitabine to malignant cells expressing tumor‐associated integrins. This KDC binds to tumor cells with low‐nanomolar affinity, is internalized by an integrin‐mediated process, releases its payload intracellularly, and is a highly potent inhibitor of brain, breast, ovarian, and pancreatic cancer cell lines. Notably, these features enable this KDC to bypass a gemcitabine‐resistance mechanism found in pancreatic cancer cells. This work expands the therapeutic relevance of knottin peptides to include targeted drug delivery, and further motivates efforts to expand the drug‐conjugate toolkit to include non‐antibody protein scaffolds.
Enaminones as Synthons for a Directed C−H Functionalization: RhIII‐Catalyzed Synthesis of Naphthalenes
Authors: Zhou Shuguang , Wang Jinhu , Wang Lili , Song Chao , Chen Kehao , Zhu Jin
Published: June 2016

The use of enaminones as effective synthons for a directed C−H functionalization is reported. Proof‐of‐concept protocols have been developed for the RhIII‐catalyzed synthesis of naphthalenes, based on the coupling of enaminones with either alkynes or α‐diazo‐β‐ketoesters. Two inherently reactive functionalities (hydroxy and aldehyde groups) are integrated into the newly formed cyclic framework and a broad range of substituents are tolerated, rendering target products readily available for further elaboration.
A Genetically Encoded β‐Lactamase Reporter for Ultrasensitive 129Xe NMR in Mammalian Cells
Authors: Wang Yanfei , Roose Benjamin W. , Palovcak Eugene J. , Carnevale Vincenzo , Dmochowski Ivan J.
Published: June 2016

Molecular imaging holds considerable promise for elucidating biological processes in normal physiology as well as disease states, but requires noninvasive methods for identifying analytes at sub‐micromolar concentrations. Particularly useful are genetically encoded, single‐protein reporters that harness the power of molecular biology to visualize specific molecular processes, but such reporters have been conspicuously lacking for in vivo magnetic resonance imaging (MRI). Herein, we report TEM‐1 β‐lactamase (bla) as a single‐protein reporter for hyperpolarized (HP) 129Xe NMR, with significant saturation contrast at 0.1 μm. Xenon chemical exchange saturation transfer (CEST) interactions with the primary allosteric site in bla give rise to a unique saturation peak at 255 ppm, well removed (≈60 ppm downfield) from the 129Xe‐H2O peak. Useful saturation contrast was also observed for bla expressed in bacterial cells and mammalian cells.
Isolation and Crystallographic Characterization of the Labile Isomer of Y@C82 Cocrystallized with Ni(OEP): Unprecedented Dimerization of Pristine Metallofullerenes
Authors: Bao Lipiao , Pan Changwang , Slanina Zdenek , Uhlik Filip , Akasaka Takeshi , Lu Xing
Published: June 2016

Although the major isomers of M@C82 (namely M@C2v(9)‐C82, where M is a trivalent rare‐earth metal) have been intensively investigated, the lability of the minor isomers has meant that they have been little studied. Herein, the first isolation and crystallographic characterization of the minor Y@C82 isomer, unambiguously assigned as Y@Cs(6)‐C82 by cocrystallization with Ni(octaethylporphyrin), is reported. Unexpectedly, a regioselective dimerization is observed in the crystalline state of Y@Cs(6)‐C82. In sharp contrast, no dimerization occurs for the major isomer Y@C2v(9)‐C82 under the same conditions, indicating a cage‐symmetry‐induced dimerization process. Further experimental and theoretical results disclose that the regioselective dimer formation is a consequence of the localization of high spin density on a special cage‐carbon atom of Y@Cs(6)‐C82 which is caused by the steady displacement of the Y atom inside the Cs(6)‐C82 cage.
Molecular Engineering of Conjugated Polybenzothiadiazoles for Enhanced Hydrogen Production by Photosynthesis
Authors: Yang Can , Ma Beatriz Chiyin , Zhang Linzhu , Lin Sen , Ghasimi Saman , Landfester Katharina , Zhang Kai A. I. , Wang Xinchen
Published: June 2016

The search for metal‐free organic photocatalysts for H2 production from water using visible light remains a key challenge. Reported herein is a molecular structural design of pure organic photocatalysts, derived from conjugated polybenzothiadiazoles, for photocatalytic H2 evolution using visible light. By alternating the substitution position of the electron‐withdrawing benzothiadizole unit on the phenyl unit as a comonomer, various polymers with either one‐ or three‐dimensional structures were synthesized and the effect of the molecular structure on their catalytic activity was investigated. Photocatalytic H2 evolution efficiencies up to 116 μmol h−1 were observed by employing the linear polymer based on a phenyl‐benzothiadiazole alternating main chain, with an apparent quantum yield (AQY) of 4.01 % at 420 nm using triethanolamine as the sacrificial agent.
Preparation and characterization of Fe3O4@SiO2/APTPOSS core–shell composite nanomagnetics as a novel family of reusable catalysts and their application in the one‐pot synthesis of 1,3‐thiazolidin‐4‐one derivatives
Authors: Safaei‐Ghomi Javad , Nazemzadeh Seyed Hadi , Shahbazi‐Alavi Hossein
Published: June 2016

Octakis[3‐(3‐aminopropyltriethoxysilane)propyl]octasilsesquioxane (APTPOSS) as a polyhedral oligomeric silsesquioxane derivative was prepared and used as a pioneer reagent to obtain a novel core–shell composite using magnetic iron oxide nanoparticles as the core and the inorganic–organic hybrid polyhedral oligomeric silsesquioxane as the shell. Fe3O4@SiO2/APTPOSS were confirmed using Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, dynamic light scattering, thermogravimetric analysis, X‐ray diffraction and vibrating sample magnetometry. The inorganic–organic hybrid polyhedral oligomeric silsesquioxane magnetic nanoparticles were used as an efficient new heterogeneous catalyst for the one‐pot three‐component synthesis of 1,3‐thiazolidin‐4‐ones under solvent‐free conditions. Moreover, these nanoparticles could be easily separated using an external magnet and then reused several times without significant loss of catalytic activity. Copyright © 2016 John Wiley & Sons, Ltd.
Influence of molecular structure and reinforcement on fatigue behavior of tough polypropylene materials
Authors: Arbeiter Florian J. , Frank Andreas , Pinter Gerald
Published: June 2016

Molecular structure and reinforcement heavily influence the crack growth resistance of polypropylene materials. Aim of this study is to investigate the fatigue behavior of different unreinforced and reinforced tough polypropylene materials used for piping applications. Due to high resistance against crack growth, these materials cannot be tested in the application relevant quasi‐brittle failure mode within feasible amounts of time. In this work, the new cyclic cracked round bar test, developed for tough polyethylene materials, has been examined as a possible method to characterize this important type of failure mode in homo‐, random‐, and reinforced polypropylene. Even though molecular mass distribution, which is often used to explain differences in crack growth resistance of polymers, was similar for unreinforced materials, fatigue lifetimes differed greatly. The mismatch of molecular mass and fatigue lifetime was mainly attributed to the different buildup and morphology of the base polymer. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43948.
Preparation and swelling behavior of moisture‐absorbing polyurethane films impregnated with superabsorbent sodium polyacrylate particles
Authors: Lee Jeong Hoon , Lee Seung Geol
Published: June 2016

Moisture‐absorbing composite films were prepared with superabsorbent sodium polyacrylate particles and solvent‐type polyurethane for applications in fabrics. To study the effect of the particle size of sodium polyacrylates on the swelling capacity and deswelling behavior of the composite films, we prepared sodium polyacrylates with different particle sizes ranging from 277 μm to 485 nm. The rate of absorption and the swelling capacity of the composite films were generally observed to increase with decreasing sodium polyacrylate particle size—except that the water absorbency of the composite film containing the very smallest, 485‐nm‐size, sodium polyacrylate particles was lower than that yielded by the larger particles, perhaps because these very small sodium polyacrylate particles were impregnated inside the polyurethane matrix rather than on the surface. Meanwhile, the deswelling behavior was not significantly affected by the particle size. Differences in the ionic solutions also significantly affected the swelling capacity of the composite film and altered its swelling kinetics. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43973.