bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication and Application of Single Crystal Fiber: Review and Prospective
Authors: Liu Bo , Ohodnicki Paul R. 
Published: July 2021

AbstractThe state of the art of single crystal fiber (SCF) fabrication has evolved and improved over the last five decades. Nowadays, edge‐defined film‐feed growth, micro‐pulling down, and laser heated pedestal growth are three major techniques for the fabrication of SCF. Solid state crystal growth and temperature gradient technology are also very active recently making small size SCF. These optical fiber growth techniques are powerful material research tools employed globally for both scientific inquiry and practical applications. This article introduces the development of SCF growth techniques, with particular emphasis on recent practical applications including temperature sensing, radiation environment sensing, fiber laser and power delivery, chemical and medical application, imaging application, and piezoelectric application. In all cases, the application‐oriented point of view provides the reader with an up‐to‐date panorama of the vast possibilities offered by SCF. In the end, perspectives on the trends and future development of single crystal fibers are discussed.
Light‐Gated Control of Conformational Changes in Polymer Brushes
Authors: Bialas Sabrina , Krappitz Tim , Walden Sarah L. , Kalayci Kubra , Kodura Daniel , Frisch Hendrik , MacLeod Jennifer M. , Nelson Andrew , Michalek Lukas , Barner‐Kowollik Christopher 
Published: July 2021

AbstractHerein, a strategy to control conformational changes in grafted polymer brushes via photoinduced crosslinking of photoreactive groups embedded into the lateral architecture of a polymer brush is reported. Poly(methylmethacrylate)‐based polymer brushes containing UV‐light (λ = 325 nm) photoreactive o‐methyl benzaldehyde moieties are synthesized using surface‐initiated reversible deactivation polymerization. The conformational changes in polymer brushes upon UV‐light triggered crosslinking are comprehensively analyzed through a full suite of surface sensitive characterization methods including time of flight secondary ion mass spectrometry, quartz crystal microbalance with dissipation monitoring, UV/vis spectroscopy, atomic force microscopy, nanoplasmonic sensing, and neutron reflectometry. The spatiotemporal control of the induced conformational changes is demonstrated via photolithography experiments. To enable an additional level of control, a second gate, the visible light (λ = 445 nm) active styrylpyrene moiety, is incorporated into the polymer brush architecture. Critically, wavelength‐selective crosslinking behavior is observed in the diblock copolymer structures allowing to crosslink specific sections of the lateral brush architecture as a function of irradiation wavelength.
Click Reaction of Selenols with Isocyanates: Rapid Access to Selenocarbamates as Peroxide‐Switchable Reservoir of Thiol‐Peroxidase‐Like Catalysts
Authors: Capperucci Antonella , Petrucci Alessandra , Faggi Cristina , Tanini Damiano 
Published: July 2021

AbstractSelenols react with isocyanates under mild catalyst‐free conditions to generate selenocarbamates in good yield and with high selectivity over potentially competing nucleophilic additions. The methodology enables the incorporation of a wide variety of functional groups providing access to a broad array of densely functionalised selenocarbamates. In the presence of competing heteroatom‐centered nucleophiles, isocyanates selectively couple with selenols. Selenocarbamates exhibited thiol‐peroxidase‐like properties, enabling the reduction of hydrogen peroxide at the expense of thiols, which are converted into the corresponding disulfides. A series of control experiments suggested that the catalytic mechanism proceeds through a pathway, involving a H2O2‐promoted transcarbamoylation reaction leading to a thiocarbamate with concomitant releasing of catalytically active selenolate anions. By undergoing peroxide‐driven thiol‐selenol exchange, selenocarbamates behave as equivalents of selenolate anions with thiol‐peroxidase‐like activity.magnified image
Carbocatalytic Cascade Synthesis of Polysubstituted Quinolines from Aldehydes and 2‐Vinyl Anilines
Authors: Mäkelä Mikko K. , Bulatov Evgeny , Malinen Kiia , Talvitie Juulia , Nieger Martin , Melchionna Michele , Lenarda Anna , Hu Tao , Wirtanen Tom , Helaja Juho 
Published: July 2021

AbstractOxidized active carbon (oAC) catalyses the formation of polysubstituted quinolines from o‐vinyl anilines and aldehydes. The reaction proceeds in a cascade manner through condensation, electrocyclization and dehydrogenation, and gives access to a wide range of quinolines with alkyl and/or aryl substituents as demonstrated with 40 examples. The metal‐free catalytic procedure allows a heterogeneous protocol for the synthesis of various polysubstituted quinolines. The mechanistic studies imply that both the acid and quinoidic groups in oAC are integral for the catalytic manifold.magnified image
Spline‐Based Drift Analysis for the Reliability of Semiconductor Devices
Authors: Hofer Vera , Nowak Thomas , Lewitschnig Horst 
Published: July 2021

AbstractDesign and production of semiconductor devices for the automotive industry are characterized by high reliability requirements, such that the proper functioning of such devices is ensured over their whole lifetime. Manufacturers subject their products to extensive testing, such as high‐temperature operating life (HTOL) tests that simulate the tough requirements products have to withstand. In the present study, the drift behavior of a representative electrical parameter under HTOL stress conditions is modeled, using linear splines, and a model for the determination of test limits used to ensure reliability is formulated. These test limits are computed such that for a predefined probability the electrical parameters under consideration remain within their specification limits over the whole product lifetime. Additionally, the yield loss that might be caused by this quality control procedure should be kept as small as possible. These test limits can then be used by automated test equipment to detect conforming and non‐conforming devices immediately after production. Extensive numerical simulations are conducted in order to demonstrate the performance of this model under a wide set of different scenarios for inter‐ and intra‐device variabilities.
Remote Modular Electronics for Wireless Magnetic Devices
Authors: Boyvat Mustafa , Sitti Metin 
Published: July 2021

AbstractSmall‐scale wireless magnetic robots and devices offer an effective solution to operations in hard‐to‐reach and high‐risk enclosed places, such as inside the human body, nuclear plants, and vehicle infrastructure. In order to obtain functionalities beyond the capability of magnetic forces and torques exerted on magnetic materials used in these robotic devices, electronics need to be also integrated into them. However, their capabilities and power sources are still very limited compared to their larger‐scale counterparts due to their much smaller sizes. Here, groups of milli/centimeter‐scale wireless magnetic modules are shown to enable on‐site electronic circuit construction and operation of highly demanding wireless electrical devices with no batteries, that is, with wireless power. Moreover, the mobility of the modular components brings remote modification and reconfiguration capabilities. When these small‐scale robotic modules are remotely assembled into specific geometries, they can achieve, if not impossible, challenging electrical tasks for individual modules. Using such a method, several wireless and battery‐free robotic devices are demonstrated using milli/centimeter‐scale robotic modules, such as a wireless circuit to power light‐emitting diodes with lower external fields, a device to actuate relatively high force‐output shape memory alloy actuators, and a wireless force sensor, all of which can be modified on‐site.
Constructing Active Sites from Atomic‐Scale Geometrical Engineering in Spinel Oxide Solid Solutions for Efficient and Robust Oxygen Evolution Reaction Electrocatalysts
Authors: Yue Xin , Qin Xueping , Chen Yangdong , Peng Yang , Liang Caihong , Feng Min , Qiu Xinzhuo , Shao Minhua , Huang Shaoming 
Published: July 2021

AbstractSpinel oxides are considered as promising low‐cost non‐precious metal electrocatalysts for oxygen evolution reaction (OER) due to their desirable catalytic activities and fast kinetics. However, as a result of the structural complexity of spinel oxides, systematic and in‐depth studies on enhancing the OER performance of spinel oxides remain inadequate. In particular, the construction of active sites regarding the large number of unoccupied octahedral interstices has not yet been explored. Herein, more octahedral sites with high OER activities are constructed on the surface of spinel oxides via a cationic misalignment, which is induced by the defects in the spinel oxide solutions, i.e., MoFe2O4 and CoFe2O4 nanosheets supported on an iron foam (MCFO NS/IF). With increased active sites and modified electronic structure, the state‐of‐the‐art electrocatalyst exhibits the excellent OER catalytic activity with an onset potential of 1.41 V versus RHE and an overpotential of 290 mV to achieve a current density of 500 mA cm−2. Moreover, such an electrocatalyst also demonstrates fast kinetics with the Tafel slope of 38 mV dec−1 and superior durability by maintaining the OER activity at 250 mA cm−2 for 1000 h.
Organic Memory and Memristors: From Mechanisms, Materials to Devices
Authors: Yuan Lei , Liu Shuzhi , Chen Weilin , Fan Fei , Liu Gang 
Published: July 2021

AbstractFacing the exponential growth of data digital communications and the advent of artificial intelligence, there is an urgent need for information technologies with huge storage capacity and efficient computing processing. However, the traditional von Neumann architecture and silicon‐based storage and computing technology will reach their limits and cannot meet the storage requirements of ultrasmall size, ultrahigh density, and memory computing. Considering these issues, organic material resistance switching memory and memristor devices have become promising candidates for high‐density storage, logic computing, and neuromorphic computing because of their advantages of fast speed, high energy efficiency, nonvolatile storage, and low cost. In this article, the working mechanism, material design strategy, and device performance of organic memory and memristors are reviewed.
Location and plant spacing affect biomass yield and nutritional value of pigeon pea forage
Authors: Mekonen Tefera , Tolera Adugna , Nurfeta Ajebu , Bradford Barry , Mekasha Aklilu 
Published: July 2021

AbstractAn experiment was conducted to evaluate the effects of row spacing (RS) and interplant spacing (IPS) on the yield of total biomass, leaf, and edible twigs, and nutritive value of pigeon pea (Cajanus cajan L. Millsp.) at three locations in the Rift Valley area of Ethiopia. The authors used a randomized completed block design with three replications in 3 × 3 factorial arrangement: three RS (25, 50, and 75 cm) and three IPS (15, 30, and 45 cm). Row spacing × IPS of 25 × 30 cm and 50 × 15 cm gave greater total biomass yield than the other RS and IPS combinations. A similar result was found for edible plant yield. At Hawassa, the greater leaf crude protein was found for the wider IPS of 45 cm than the narrower IPS of 30 cm (318 vs. 303 g kg–1). At Wondo‐Genet, the greater leaf in vitro digestible organic matter (597 vs. 582 g kg–1) was found for the wider RS of 75 cm than narrower RS. Similar to leaf, a better nutritional value of edible twigs was found for a wider RS and IPS than narrower RS and IPS at Hawassa and Wondo‐Genet. In contrast at Aliyu‐Amba, a better nutritional value of edible twigs was found for narrower RS and IPS than the wider spacing. Thus, it can be concluded that RS × IPS of 25 × 30 cm or 50 × 15 cm are advisable for pigeon pea forage production.
Beef cattle feeding costs as impacted by hay yield and quality
Authors: Rushing J. Brett , Lemus Rocky W. , Maples Joshua G. , Rivera J. Daniel , Lyles Johnson C. 
Published: July 2021

AbstractReducing dependence onstored feed, particularly dry hay, is a major factor in beef cattle production systems in the southeastern United States. Increasing the nutritive value of the hay that is fed, however, can ultimately reduce total feed costs and boost profitability. A field trial was conducted in east‐central Mississippi evaluating several warm‐season perennial grass hay crops under varying N and harvest regimes in order to assess their ability to meet beef cow nutritional demands and to estimate total feed costs. Cultivars included ‘Argentine’ (ARG) and ‘Pensacola’ (PEN) bahiagrass (Paspalum notatum Flueggé), ‘Common’ (COM) and ‘Cheyenne II’ (CHE) bermudagrass (Cynodon dactylon L.), and ‘Pete’ (PET) eastern gamagrass (Tripsacum dactyloides L.). Plots were assigned to an annual N treatment (0, 112, 224, 336, or 448 kg N ha−1 yr−1) and a harvest frequency (30, 40, 60, and 120 d). Argentine produced the greatest amount of forage mass (FM) at the 448 kg N ha−1 yr−1 rate (14,422 kg DM ha−1). Increasing N rates resulted in greater mean crude protein (CP) values, whereas harvest frequency had a greater impact on total digestible nutrients (TDN). Total feed costs were calculated based on field trial data and were combined with either soybean [Glycine max (L.) Merr.] hulls (SH) or corn (Zea mays L.) gluten (CG) to match nutritional demand. The most economical feed costs were those where hay was fertilized (>224 kg N ha−1 yr−1) and harvested three or more times a year and was combined with CG.
Cotton cultivar response to potassium fertilizer application in Texas’ southern high plains
Authors: Kusi Nana Yaw O. , Lewis Katie L. , Morgan Gaylon D. , Ritchie Glen L. , Deb Sanjit K. , Stevens Richard D. , Sintim Henry Y. 
Published: July 2021

AbstractCotton (Gossypium hirsutumL.) and potassium (K) dynamics are not well understood particularly in soils with high K levels. Potassium is important for cotton reproductive development as it influences the number, size, and weight of bolls and can improve fiber quality by mitigating moisture stress. In the case that soil cannot replenish solution K from exchangeable reserves to meet the plant demands, deficiencies may occur leading to decreased yield (lint and seed) and fiber quality, reduced drought and disease tolerance, and premature boll opening. Studies were conducted in 2016 and 2017 in Lubbock (Olton clay loam and Acuff loam) and Lamesa (Amarillo fine sandy loam), TX, to determine the effects of K application rates and timing on lint yield and fiber quality of modern cotton cultivars (DP 1518 B2XF, DP 1522 B2XF, DP 1321 B2XF, and DP 1612 B2XF). Pre‐plant soil tests were >250 mg K kg–1at both locations and years at the 0‐to‐15‐cm soil depths. Potassium treatments were applied at 0 (control), 90, and 180 kg K ha–1as pre‐plant, side‐dress, or split applications. Harvest results determined that pre‐plant and side‐dress K applications produced significantly greater lint yield only for DP 1518 B2XF at both locations, while effects on fiber quality varied by location. The response of DP 1518 B2XF to K fertilizer was due to greater K use efficiency and possibly K demand of this cultivar compared to the others. This research provides evidence for continued investigation of cultivar by environment‐based K management.
Identification of M‐NH2‐NH2 Intermediate and Rate Determining Step for Nitrogen Reduction with Bioinspired Sulfur‐Bonded FeW Catalyst
Authors: Zhao Yilong , Li Fusheng , Li Wenlong , Li Yingzheng , Liu Chang , Zhao Ziqi , Shan Yu , Ji Yongfei , Sun Licheng 
Published: July 2021

AbstractThe multimetallic sulfur‐framework catalytic site of biological nitrogenases allows the efficient conversion of dinitrogen (N2) to ammonia (NH3) under ambient conditions. Inspired by biological nitrogenases, a bimetallic sulfide material (FeWSx@FeWO4) was synthesized as a highly efficient N2 reduction (NRR) catalyst by sulfur substitution of the surface of FeWO4 nanoparticles. Thus prepared FeWSx@FeWO4 catalysts exhibit a relatively high NH3 production rate of 30.2 ug h−1 mg−1cat and a Faraday efficiency of 16.4 % at −0.45 V versus a reversible hydrogen electrode in a flow cell; these results have been confirmed via purified 15N2‐isotopic labeling experiments. In situ Raman spectra and hydrazine reduction kinetics analysis revealed that the reduction of undissociated hydrazine intermediates (M‐NH2‐NH2) on the surface of the bimetallic sulfide catalyst is the rate‐determing step for the NRR process. Therefore, this work can provide guidance for elucidating the structure–activity relationship of NRR catalysts.
Suppressing fire hazard of poly(vinyl alcohol) based on (NH4)2[VO(HPO4)]2(C2O4)·5H2O with layered structure
Authors: Zhu Haojie , Chen Yongming , Huang Shuai , Wang Yuan , Yang Ru , Chai Huiyu , Zhu Fang , Kong Qinghong , Zhang Yunlong , Zhang Junhao 
Published: July 2021

AbstractTwo‐dimensional layered ammonium vanadium oxalate‐phosphates (AVOPh) with the structural formula of (NH4)2[VO(HPO4)]2(C2O4)·5H2O are synthesized though a hydro‐thermal method, which is dispersed into poly(vinyl alcohol) (PVA) matrix to prepare PVA/AVOPh composites. The results of thermal analysis indicate that AVOPh and PVA have similar decomposition temperature from 280 to 500°C, which is critical for choosing flame retardant. The incorporation of AVOPh significantly improves the thermal stability and flame retardancy of PVA/AVOPh composites that the T5% value of PVA/2 wt% AVOPh composites is up to 215°C, and the residue of PVA/8 wt% AVOPh composites is enhanced to 16.9%, while those of pure PVA are only 178°C and 2.4%. PVA/4 wt% AVOPh composites can pass V‐0 level, and its limiting oxygen index value is up to 32.0%. Furthermore, the peak heat release rate (PHRR) and total heat release (THR) of PVA/AVOPh composites are obviously decreased, which reduced by 43.4% and 43.8% with the addition of 4 wt% AVOPh, compared with those of pure PVA. The excellent thermal stability and flame retardancy are mainly attributed to the uniform dispersion and barrier effect of 2D layered AVOPh, the release of crystal water, ammonia and phosphorus free radicals and the two‐phase flame retardant catalytic mechanism of vanadium and phosphorus.
Highly porous, water‐swellable, and reusable chelating polymeric gels for heavy metal ion removal from aqueous waste
Authors: Tyagi Reshu , Jacob Josemon 
Published: July 2021

AbstractSequestration and removal of heavy metal ions from aqueous solutions pose multiple challenges. Ease of synthesis, high adsorption capacity and ease of regeneration are important considerations in the design of polymeric adsorbent materials developed for this purpose. To meet this objective, a new approach was used to design and synthesize a highly porous polystyrene‐based resin (IDASR15) bearing iminodiacetate functional groups in every repeat unit by free radical polymerization with N, N'‐methylenebisacrylamide as crosslinker followed by base hydrolysis. The physiochemical chemical properties of the resin were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, equilibrium swelling value (ESV) and thermogravimetric analysis. Metal uptake capacity of IDASR15 towards low concentrations of various toxic heavy metal ions such as Cu2+, Cd2+, Mn2+, Zn2+, Pb2+, Ni2+, Co2+, Co3+, Cr3+, Fe2+, Fe3+, and Al3+ were investigated from their aqueous solution by batch method and found to be 0.943–2.802 mmol/g. The maximum capacity was 2.802 mmol/g obtained for Cu2+ ion at pH 5. The potential for regeneration and reuse has been demonstrated with Cu2+ ion by batch and column methods. The reported results suggest that IDASR15 is a highly efficient and porous complexing agent for commonly found toxic metal ions in aqueous streams with a high ESV of 68.55 g of water/1.0 g of IDASR15. It could also be reused ~99.5% of adsorption efficiency which is very promising and holds significant potential for waste‐water treatment applications.
Elucidating the interactions between carbon nanotubes and carbon black with styrene butadiene rubber
Authors: García Daniela B. , Mansilla Marcela A. , Monsalve Leandro N. , Bilbao Emanuel , Garraza Ana Lucía Rodríguez , Escobar Mariano M. 
Published: July 2021

AbstractThe reinforcement mechanism of carbon nanotubes (CNT) on styrene butadiene rubber is studied through dynamic and swelling tests. Compounds containing carbon black (CB) and an unfilled one were prepared for comparison purposes. The dynamic properties are interpreted through the Maier‐Göritz model to distinguish the contributions of stable and unstable crosslinks to the storage modulus, finding that the unstable ones become more relevant in samples containing a CNT concentration higher than 5 phr. In addition, the crosslinks density estimated by swelling and the stable contribution obtained with dynamical properties present the same tendency with the CNT amount. The former presents lower values, which can be explained considering that only stable crosslinks remain in the equilibrium‐swollen state, while in the second one both stable and unstable are considered. In addition, differences in the filler‐polymer interaction mechanisms are observed according to the morphology and aspect ratio of CNT in contrast to CB.
An in vitro evaluation of Genipin‐crosslinked and Hypericum perforatum incorporated novel membranes for skin tissue engineering applications
Authors: Ceylan Seda 
Published: July 2021

AbstractIncorporating medicinal plant extracts in membranes have a great potential as scaffolds for tissue engineering applications or vehicles for delivering therapeutic agents. Herein, Hypericum perforatum oil (0.25, 0.50, % vol/vol) loaded membranes were developed with Polyvinyl alcohol and chitosan polymer, where Genipin works as a chemical crosslinker to obtain a wound dressing material with acceptable characterization properties. Chemical groups, surface morphology, water uptake capacity, water vapor permeability rate, hydrophilicity, and mechanical properties of membranes were thoroughly investigated. Increasing oil concentration had a significant effect on the water uptake, surface morphology. and water vapor permeability rate of the membranes. Cytocompatibility of the membrane was also investigated with mouse embryonic fibroblasts (MEF) by 3‐(4,5‐dimethylthiazoyl‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay for direct and indirect cell culture studies. SEM was used to investigate the cell morphology on the membranes. The MTT assay findings prove that Genipin crosslinked H. perforatum oil loaded scaffolds are highly biocompatible and enhance the adhesion and proliferation of MEF cells. In addition to this, the genotoxicity test was performed to show DNA fragmentation. Results showed that the H. perforatum oil loaded polyvinyl alcohol‐chitosan membrane presents suitable properties for potential skin tissue engineering applications.
Effect of creep on the mode II residual fracture energy of adhesives
Authors: Carneiro Neto Ranulfo M. , Akhavan‐Safar Alireza , Sampaio Eduardo M. , Assis Joaquim T. , da Silva Lucas F. M. 
Published: July 2021

AbstractViscous flow that often occurs in adhesive materials leads to a permanent deformation when adhesives are subjected to creep loading. Creep loading has a significant influence on the strength of bonded structures. Due to the viscous behavior, the fracture energy also may change with time for joints that experience creep loading in service. In this work the effects of two creep parameters (creep load and time) on the residual mode II fracture energy of an adhesive was investigated using end notched flexure (ENF) specimens. To achieve this, ENF samples were subjected to different creep loading levels at different creep times followed by quasi static tests to obtain the residual shear fracture energy of the adhesive. Experimental results showed that pre‐creep loading of the bonded structures can significantly improve the fracture energy and the static strength of the joints.