bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zirkuläre Lösungen für Kunststoffe
Authors: Erhardt Götz 
Published: December 2020

AbstractChemieunternehmen kennen sich mit Werkstoffen aus und produzieren Polymere. Daher sind die Unternehmen in der Lage, Plastikmüll zu reduzieren: Sie können sowohl neue Materialien entwickeln als auch die Kreislaufwirtschaft fördern.
Angewandte Ethik: Wegweiser in einer Technikgesellschaft
Authors: Hartmann Jens 
Published: December 2020

AbstractDamit Ethik nicht die „Fahrradbremse am Interkontinentalflugzeug“ bleibt, wie es der Soziologe Ulrich Beck in den 1970er Jahren beschrieben hat, müssen sich auch Naturwissenschaftler und Ingenieure damit befassen. Ethische Reflexionen über Fortschritt und Technik erfordern zeitige Sensibilisierung und entsprechende Bildung.
Underwater superpolymphobicity: Concept, achievement, and applications
Authors: Yong Jiale , Yang Qing , Hou Xun , Chen Feng 
Published: December 2020

AbstractPolymers are the most common materials in our daily lives. Reducing the adhesion between liquid polymers (LPs) and the solid substrate has great significance in manipulating and using polymers. However, the wetting behavior of an LP on a solid surface has rarely been studied compared to the extensively studied water, oils, and bubbles. Recently, the concept of underwater superpolymphobicity that a solid surface has great repellence to LPs in water was proposed. In this review, we summarize the recent advance of underwater superpolymphobicity, mainly focusing on its concept, achievement, and potential applications. Underwater superpolymphobic microstructures can be prepared on various hydrophilic substrates by the formation of proper hierarchical microstructures. The underwater superpolymphobicity can be used to reduce the adhesion of polymers on a material surface, design the shape of polymers, and separate LPs from water. We believe that the underwater superpolymphobicity may soon be in the polymers‐related applications, for example, polymer production, packing, casting industry, polymer shaping, and 3D printing.
Retrospective respiratory motion correction in cardiac cine MRI reconstruction using adversarial autoencoder and unsupervised learning
Authors: Ghodrati Vahid , Bydder Mark , Ali Fadil , Gao Chang , Prosper Ashley , Nguyen Kim‐Lien , Hu Peng 
Published: December 2020

AbstractThe aim of this study was to develop a deep neural network for respiratory motion compensation in free‐breathing cine MRI and evaluate its performance. An adversarial autoencoder network was trained using unpaired training data from healthy volunteers and patients who underwent clinically indicated cardiac MRI examinations. A U‐net structure was used for the encoder and decoder parts of the network and the code space was regularized by an adversarial objective. The autoencoder learns the identity map for the free‐breathing motion‐corrupted images and preserves the structural content of the images, while the discriminator, which interacts with the output of the encoder, forces the encoder to remove motion artifacts. The network was first evaluated based on data that were artificially corrupted with simulated rigid motion with regard to motion‐correction accuracy and the presence of any artificially created structures. Subsequently, to demonstrate the feasibility of the proposed approach in vivo, our network was trained on respiratory motion‐corrupted images in an unpaired manner and was tested on volunteer and patient data. In the simulation study, mean structural similarity index scores for the synthesized motion‐corrupted images and motion‐corrected images were 0.76 and 0.93 (out of 1), respectively. The proposed method increased the Tenengrad focus measure of the motion‐corrupted images by 12% in the simulation study and by 7% in the in vivo study. The average overall subjective image quality scores for the motion‐corrupted images, motion‐corrected images and breath‐held images were 2.5, 3.5 and 4.1 (out of 5.0), respectively. Nonparametric‐paired comparisons showed that there was significant difference between the image quality scores of the motion‐corrupted and breath‐held images (P < .05); however, after correction there was no significant difference between the image quality scores of the motion‐corrected and breath‐held images. This feasibility study demonstrates the potential of an adversarial autoencoder network for correcting respiratory motion‐related image artifacts without requiring paired data.
2D time‐domain full‐waveform inversion of SH‐ and Love‐waves for geotechnical site characterization
Authors: Chen Ruoyu , Tran Khiem T. , Wang Yao 
Published: December 2020

ABSTRACTFull‐waveform inversion has proved to be an effective and robust approach for near‐surface site characterization. Past full‐waveform inversion studies have mostly focused on Rayleigh wave, with only a few studies focussing on SH‐ and Love‐waves. Compared with Rayleigh waves, the main advantages of using SH‐ and Love‐waves are that they are more sensitive to mass density of materials and require much less computing time for simulation. In this study, we present an efficient SH‐ and Love‐wave full‐waveform inversion method to extract both S‐wave velocity and mass density of soil and rock. The method is based on the solution of 2D elastic SH‐wave equations and the adjoint‐state gradient approach with an implementation of Tikhonov regularization. We use synthetic and field experiments to test the capability of the method. The synthetic experiment indicates that the presented method can accurately characterize a challenging soil profiel represented by the presence of a velocity reversal along with variable layers of high and low S‐wave velocity and density. Variable layer interfaces, true S‐wave velocity and density values are well recovered. The field experiment successfully characterizes the subsurface structure to a depth of 18 m, that includes a soil layer underlain by limestone bedrock. Two invasive standard penetration tests were conducted to verify the inverted seismic results. The trend in depth of the standard penetration test N‐values generally agrees with the inverted results, including identification of a soft soil layer.
Error estimation for second‐order partial differential equations in nonvariational form
Authors: Blechschmidt Jan , Herzog Roland , Winkler Max 
Published: December 2020

AbstractSecond‐order partial differential equations (PDEs) in nondivergence form are considered. Equations of this kind typically arise as subproblems for the solution of Hamilton–Jacobi–Bellman equations in the context of stochastic optimal control, or as the linearization of fully nonlinear second‐order PDEs. The nondivergence form in these problems is natural. If the coefficients of the diffusion matrix are not differentiable, the problem cannot be transformed into the more convenient variational form. We investigate tailored nonconforming finite element approximations of second‐order PDEs in nondivergence form, utilizing finite‐element Hessian recovery strategies to approximate second derivatives in the equation. We study both approximations with continuous and discontinuous trial functions. Of particular interest are a priori and a posteriori error estimates as well as adaptive finite element methods. In numerical experiments our method is compared with other approaches known from the literature.
Diversifying environmental volunteers by engaging with online communities
Authors: Winch Kayleigh , Stafford Richard , Gillingham Pippa , Thorsen Einar , Diaz Anita 
Published: December 2020

Abstract

Environmental volunteering can benefit participants and nature through improving physical and mental well‐being while encouraging environmental stewardship. To enhance achievement of these outcomes, conservation organizations need to reach different groups of people to increase participation in environmental volunteering. This paper explores what engages communities searching online for environmental volunteering.

We conducted a literature review of 1,032 papers to determine key factors fostering participation by existing volunteers in environmental projects. We found that the most important factor was to tailor projects to the motivations of participants. Also important were promoting projects to people with relevant interests, meeting the perceived benefits of volunteers and removing barriers to participation.

We then assessed the composition and factors fostering participation of the NatureVolunteers's online community (n = 2,216) of potential environmental volunteers and compared findings with those from the literature review. We asked whether projects advertised by conservation organizations meet the motivations and interests of this online community.

Using Facebook insights and Google Analytics we found that the online community were on average younger than extant communities observed in studies of environmental volunteering. Their motivations were also different as they were more interested in physical activity and using skills and less in social factors. They also exhibited preferences for projects which are outdoor based, and which offer close contact with wildlife. Finally, we found that the online community showed a stronger preference for habitat improvement projects over those involving species survey‐based citizen science.

Our results demonstrate mismatches between what our online community are looking for and what is advertised by conservation organizations. The online community are looking for projects which are more solitary, more physically active and more accessible by the organized transport. We discuss how our results may be used by conservation organizations to better engage with more people searching for environmental volunteering opportunities online.

We conclude that there is a pool of young people attracted to environmental volunteering projects whose interests are different to those of current volunteers. If conservation organizations can develop projects that meet these interests, they can engage larger and more diverse communities in nature volunteering.

A free Plain Language Summary can be found within the Supporting Information of this article.
High frequency percussive ventilation in pediatric acute respiratory failure
Authors: Butler Andrew D. , Dominick Cheryl L. , Yehya Nadir 
Published: December 2020

AbstractObjectiveHigh frequency percussive ventilation (HFPV) is used in acute respiratory failure, but is poorly described in pediatrics. We aimed to describe the clinical characteristics, ventilator settings, and outcomes of a large pediatric cohort, and to determine predictors of who would benefit from HFPV.HypothesisGas exchange 2 h after HFPV initiation predicts success.DesignSingle center retrospective cohort study testing association between gas exchange 2 h after HFPV initiation with success, defined a priori.PatientsIntubated children on HFPV for ≥2 h from 2012 to 2018.MethodsWe described indications, ventilator settings, and gas exchange immediately before, 2 h after, and at termination of HFPV. Univariate and multivariate regression tested association of oxygenation and ventilation after HFPV initiation with success. Areas under the receiver operating characteristic (AUROC) curve and adjusted odds ratios (aORs) were computed.ResultsWe performed 237 courses of HFPV in 193 children (22% non‐survivors), of which 162 (68%) were successful. In univariate analysis, pH (AUROC, 0.65) and PCO2 (AUROC, 0.66) 2 h after HFPV predicted success. In multivariate analysis, pH (aOR: 1.67 per 1 SD; 95% confidence interval [CI]: 1.19–2.35), PCO2 (aOR: 0.49 per 1 SD; 95% CI: 0.31–0.79), and oxygenation index (aOR: 0.66 per 1 SD; 95% CI: 0.44–0.97) 2 h after HFPV initiation were associated with success.ConclusionWe describe the largest cohort of HFPV to date, with detailed description of indications and settings. Gas exchange after 2 h of HFPV was independently associated with success.
What remains today of pre‐industrial Alpine rivers? Census of historical and current channel patterns in the Alps
Authors: Hohensinner Severin , Egger Gregory , Muhar Susanne , Vaudor Lise , Piégay Hervé 
Published: December 2020

AbstractTo date, no survey on the diverse channel patterns existing prior to the major phase of river regulation in the mid‐19th–early 20th century has been elaborated at the scale of the whole European Alps. The present paper fills this knowledge gap. The historical channel forms of the 143 largest Alpine rivers with catchments larger than 500 km2 (total length 11,870 km) were reconstructed based on maps dating from the 1750s to 1900. In the early 19th century, one‐third of the large Alpine rivers were multi‐channel rivers. Single‐bed channels oscillating between close valley sides were also frequent in the Alps (28%). Sinuous and even more so meandering channels were much rarer. Historical river patterns generally followed an upstream–downstream gradient according to slope condition, floodplain width and distance from the sources. The local occurrence of certain channel patterns, however, primarily reflected the tectonic/orographic conditions. Multi‐channel reaches were widespread within the whole Alpine area, alternating with confined and oscillating reaches. This demonstrates that most areas were mainly transport‐limited rather than supply limited. Sinuous and meandering reaches were more frequent in the north‐eastern Alps and were characterized by lower denudation rates and less sediment delivery.Channel straightening caused the loss of about 510 km of river course length, equivalent to 4.3% of the historical extent. Multi‐channel stretches are currently a mere 15% of their historical length, and 45% of the larger Alpine rivers are intensively channelized or have been transformed into reservoirs. Channelization measures differed from one country to another. Human pressures directly affected both local channel geometry and the upstream controls (i.e., sediment supply). Accordingly, individual multi‐channel reaches also evolved into single‐thread channels without any local human interventions.
Cobalt‐Molybdenum Bimetal Phosphides Encapsulated in Carbon as Efficient and Durable Electrocatalyst for Hydrogen Evolution
Authors: Shi Jiazi , Hou Cunxia , Li Le , Xu Wencai , Fu Yabo , Huang Yanzhi , Xiong Ziyi , Cheng Weijia 
Published: December 2020

AbstractHydrogen evolution reaction (HER) from water electrolysis is an attractive technique developed in recent years for clean renewable energy. It is critical to develop a low‐cost, high activity and long‐time stability HER catalyst. In this work, a novel catalyst, Cobalt‐Molybdenum bimetal phosphides encapsulated in carbon matrix (Co‐Mo‐P@C), is synthesized using MOFs‐templated strategy by chemical vapor deposition (CVD) and phosphidation. The Co‐Mo‐P@C catalyst exhibits excellent catalytic performances with low overpotentials of 148 and 159 mV to reach current densities of 10 mA cm−2 for HER in both acidic and alkaline media, respectively, as well as long‐time durability over 20 h. This work introduces a new method for an efficient and stable HER catalyst and it may be extended to design other encapsulated bimetal nitrides, sulfides, and selenides for more applications.
Synthesis of Porous Mo2C/Nitrogen‐Doped Carbon Nanocomposites for Efficient Hydrogen Evolution Reaction
Authors: Li Siwei , Dong Baichuan , Yuanyuan  , Zhang  , Xu Ping 
Published: December 2020

AbstractTransition metal carbides are considered to be promising non‐precious catalysts for electrochemical hydrogen evolution reaction (HER) because of their similar electronic structures to platinum‐based materials. In this work, we report the synthesis of porous nanocomposites consisting of β‐Mo2C nanoparticles supported on nitrogen‐doped carbon (NC) for efficient HER in both acidic and alkaline conditions. It is revealed that compared to the counterpart prepared through a one‐step annealing, the two‐step carbonization product (Mo2C/NC‐2) not only owns more catalytic active Mo2C sites on the surface, but also has electron interaction between Mo2C and NC. As a consequence, Mo2C/NC‐2 provides a geometric catalytic current density of −10 mA cm−2 at overpotentials of 169 mV and 180 mV vs. reversible hydrogen electrode (RHE) and Tafel slopes of 55 and 60 mV dec−1 in 0.5 M H2SO4 and 1 M KOH, respectively. This study provides valuable insights into the preparation of transition metal carbides with modulated surface structure and remarkable electrocatalytic activity for HER.
Design, Synthesis, In Silico Studies and In Vitro Anticancer Activity of 3‐(4‐Methoxyphenyl)azetidine Derivatives
Authors: Parmar Deepa R. , Rayani Rahul H. , Vala Anand G. , Kusurkar Rakesh V. , Manvar Roshani K. , Talukdar Sahista N. , Preeti  , Zunjar Vishwanath , Battula Satyanarayana , Soni Jigar Y. 
Published: December 2020

AbstractA series of 3‐(4‐methoxyphenyl)azetidine analogues were synthesized and screened for their in vitro anticancer activity against nine different human cancer cell lines using the cell counting kit‐8 (CCK‐8) assay. The synthesized molecules were characterized by 1H NMR, 13C NMR, LCMS and IR analysis. The toxicity, bioavailability and lipophilicity of all the synthesized compounds were predicted by using osiris and molinspiration model. Molecular docking study revealed that, compound 6‐(3‐(3‐(2‐aminopyridin‐4‐yl)‐4‐methoxyphenyl)azetidin‐1‐yl)picolinonitrile (4 A‐17) and 6‐(3‐(4‐methoxy‐3‐(2‐methoxypyridin‐4‐yl)phenyl)azetidin‐1‐yl)picolinonitrile (4 A‐19) were found to be potential inhibitor of human topoisomerase IIα. The cell viability studies exhibited promising antiproliferative activities of the novel synthesized compounds. 4 A‐17 (EC50 0.03 μM) was found to be more potent than standard Doxorubicin (EC50 0.07 μM) in U251 cancer cell lines. Similarly, 4 A‐19 showed considerable potency against four different cancer cell lines (HepG2, U251, A431, 786‐O) with EC50 values ranging from 0.46 to 2.13 μM. These primary findings supported that molecule 4 A‐17 and 4 A‐19 should be subjected to further studies and lead optimization.
Synthesis of 2‐O‐Functionalized‐5‐salicyloyl Pyridine Derivatives Catalyzed by 2‐Mercaptobenzimidazole
Authors: Alizadeh Abdolali , Bagherinejad Akram 
Published: December 2020

AbstractA concise and efficient one‐pot sequential approach for the synthesis of 5‐salicyloyl pyridine frameworks was developed from a reaction of 3‐formylchromones, malononitrile, various alcohols, and 2‐mercaptobenzimidazole as a catalyst. Malononitrile is the nitrogen source in this reaction. In this method, the variety of 2‐alkoxypyridines derivatives containing alkoxy, allyloxy, and acetylene functional groups can increase the bathochromic effect of the λmax of pyridine to the longer wavelengths. According to experimental and theoretical investigations by the DFT method, long‐wavelength bands of 5‐salicyloyl pyridine derivatives related to the HOMO→LUMO and HOMO→LUMO+1 transitions have the π→π* nature and are caused by intramolecular charge transfer from the phenol fragment to the pyridine ring.
Cu/Cu2O@g‐C3N4: Recyclable Photocatalyst under Visible Light to Access 2‐Aryl‐/benzimidazoles/benzothiazoles in Water
Authors: Singh Puneet K. , Bhardiya Smita R. , Asati Ambika , Rai Vijai K. , Singh Manorama , Rai Ankita 
Published: December 2020

AbstractAn unprecedented Cu/Cu2O@g‐C3N4 catalysed visible light driven green synthesis of 2‐aryl‐/benzimidazoles and benzothiazoles is reported via condensation of structurally different aldehydes with o‐phenylenediamine and o‐aminothiophenol respectively. Herein, Synergistic catalysis is operating as both Cu/Cu2O@g‐C3N4 and visible‐light condition are required, no product was isolated in absence of either. Operational simplicity, ambient reaction conditions, aqueous medium, good yield of products (80–94 %) and recyclability of the catalyst without any loss in catalytic efficiency and selectivity are salient features of the envisaged protocol.
Synthesis, Characterization and Investigation of Hydrogen Evolution Activity of Ni‐Mo/Al2O3 Composite
Authors: Salarvand V. , Mahmoodi H. , Ahmadian F. , Farahbakhsh N. , Yousefifar A. , Saghafi M. , Noghani M. T. 
Published: December 2020

AbstractIn the present study, the hydrogen evolution activity of the Ni−Mo/Al2O3 catalyst was investigated. This catalyst was produced by milling of oxide precursors of nickel oxide (NiO) and molybdenum trioxide (MoO3) with aluminum as a reducing agent. So that oxide precursors with 100 % excess aluminum on stoichiometric composition at different times were milled to perform complete reduction operations. Subsequently, X‐ray diffraction (XRD) analysis was performed for phase analysis and scanning electron microscopy (SEM) was used to investigate the microstructure. It was found that oxide precursors with 100 % excess aluminum on stoichiometric composition were reduced after 50 h of milling and nickel molybdenum/alumina composite was produced. On the other hand, to compare the activity of Ni−Mo/Al2O3 two different catalysts (57 NiMo, 80 NiMo) were also produced by the milling method. The specimens were transformed into pills of 10 mm in diameter and 3 mm in height at 900 MPa pressure. A furnace under an argon atmosphere at a temperature of 1400 °C was used to sinter the produced pills. Finally, the hydrogen evolution activity of this sample was investigated by linear polarization tests and impedance spectroscopy in 1 M KOH solution. The sample reduced with 100 % excess aluminum showed higher activity than the stoichiometric combination, with −62 mV cathodic‐Tafel slope, −70 mV over‐potential at a current density of −10 mA cm−2 and a charge transfer resistance of 126.6 ohms.
Ink‐Assisted Synthetic Strategy for Stable and Advanced Composite Electrocatalysts with Single Fe Sites
Authors: Zhang Zhengyuan , Hao Jinhui , Lu Yahui , Xu Yuqi , Li Longhua , Shi Weidong 
Published: December 2020

AbstractThe oxygen evolution reaction is critical to the efficiency of many energy technologies that store renewable electricity in chemical form. However, the rational design of high‐performance and stable catalysts to drive this reaction remains a formidable challenge. Here, a facile ink‐assisted strategy to construct a series of stable and advanced composite electrocatalysts with single Fe sites for permitting seriously improved performance characteristics is reported. As revealed by a suit of characterization techniques and theoretical methods, the improved electrocatalytic performance and stability can be attributed to the unique coordination states of Fe in the form of distorted FeO4C and the interfacial effect in the composite system that optimize and stabilize single Fe sites in changing to better configurations for intermediates adsorption. The findings provide a novel strategy to in‐depth understanding of practical guidelines for the electrocatalyst design for energy conversion devices.
Experimental study on seismic performance of steel fiber reinforced concrete wall piers
Authors: Babaei Ali , Mortezaei Alireza , Salehian Hamidreza 
Published: December 2020

AbstractExtensive damage to the bridges in recent earthquakes has revealed the vulnerability of these structures to the seismic excitation. Bridge piers play a key role in maintaining the operability of the bridge structure during and after earthquakes. As determinant elements in single‐pier bridges, wall piers significantly affect the bridge structure behavior. Hence, the present experimental study was conducted to examine the seismic performance of wall piers made of modern materials, that is, fiber reinforced concrete (FRC) in RC bridges. Eight wall piers made of steel fiber reinforced concrete (SFRC) with different aspect ratios, steel percentages and concrete strength were subjected to lateral load. The results showed that using SFRC reduced the steel strain within the serviceability range. Compared to conventional concrete, SFRC changes failure modes and deformational characteristics and also increases the energy dissipation capacity, stiffness in every drift values, load‐bearing capacity as well as yielding length.