bluuebunny/crossref_metadata_2025_split huggingface dataset:
Convenient Cr(VI) Removal from Aqueous Samples: Executed by a Promising Clay‐Based Catalytic System, Magnetized by Fe3O4 Nanoparticles and Functionalized with Humic Acid
Authors: Hajizadeh Zoleikha , Valadi Kobra , Taheri‐Ledari Reza , Maleki Ali 
Published: February 2020

AbstractHere, a nanoscale efficient adsorbent for chromium(VI) ion is presented, which is constructed of halloysite nanotubes (HNTs) as a natural basis. On the other hand, to add magnetic property, iron oxide (Fe3O4) nanoparticles have been incorporated inside and leaded onto the surface of HNTs. As the main component of nanoabsorbent, humic acid (HA) is also loaded onto the surface of HNT/Fe3O4 nanocomposite. Cr(VI) removal process has been carefully monitored in the presence of the fabricated HNT/Fe3O4‐HA nanoabsorbent from aqueous solutions with different concentrations of K2CrO4. The adsorption isotherms are interpreted by Langmuir graphs, and 98% removal efficiency (RE) has been obtained at room temperature, in 15 min contact time. Additionally, all the analyses related to the structure of desired product have been done, and the recyclability of produced nanoabsorbent is precisely investigated, as well.
12‐Tungstosilicic Acid H4[W12SiO40] Over Natural Bentonite as a Heterogeneous Catalyst for the Synthesis of 3,4‐dihydropyrimidin‐2(1H)‐Ones
Authors: V Chopda Lakha , Dave Pragnesh N. 
Published: February 2020

AbstractRegionally available bentonite was modified by using heteropolyacid 12‐tungstosilicic acid H4[W12SiO40] (TSA). The prepared 10–30 % TSA/bent catalysts were characterized by XRD, FTIR, FeSEM and EDS. The catalytic activity of all three samples was studied on classical Biginelli reaction. Among all, 30 % TSA/bent displayed high catalytic activity and reusability. The effect of solvent was also undertaken to find the best media for the reaction. This protocol was extended to various aldehydes for the synthesis of different dihydropyrimidones (DHPMs) in high yields in ethanol.
Three‐Dimensional ZnMn2O4 Nanoparticles/Carbon Cloth Anodes for High‐Performance Flexible Lithium‐Ion Batteries
Authors: Dong Liang , Hao Jin , Liu Huiyin , Shi Wenhui , Yang Jialin , Lian Jianshe 
Published: February 2020

AbstractNanomaterials typically achieve high capacity with their high specific surface area, but they usually aggregate easily due to high surface free energy, which results in capacity rapid deterioration. Herein, ultra‐small ZnMn2O4 nanoparticles with a size of about 25–50 nm were uniformly grown on the surface of a carbon cloth (CC) current collector via a simple solvothermal method. The supporting CC can effectually suppress the agglomeration of nanoparticles, alleviate the volume effect, provide more active sites for electrochemical reactions and increase specific surface area. Moreover, the in‐situ growth of ZnMn2O4 nanoparticles without binders can enhance electrical conductivity and accelerate charge transportation. As expected, the ZnMn2O4 nanoparticles/CC electrode yields a high area capacity of 3.10 mAh cm−2 after 100 cycles at 0.12 mA cm−2 (corresponding to 1366.7 mAh g−1 for the ZnMn2O4 nanoparticles), which is much higher than the ZnMn2O4 powder and CC. Furthermore, at a high current density of 2.4 mA cm−2, the ZnMn2O4 nanoparticles/CC electrode can still maintain a high area capacity of 1.48 mAh cm−2, which indicates that ZnMn2O4 nanoparticles/CC electrodes are promising flexible anode materials for LIBs and have potential applications in wearable devices.
Asymmetric Michael Addition of Unactivated Ketones with β‐Nitrostyrenes Mediated by Bifunctional L‐Prolinamide Organocatalysts
Authors: Rani Dixita , Bhargava Meha , Agarwal Jyoti 
Published: February 2020

AbstractThe catalytic activity of two types of L‐prolinamide organocatalysts was investigated for asymmetric Michael addition reaction of cyclic/acyclic ketones with β‐nitrostyrens. L‐Prolinamides bearing amino groups on phenyl ring worked well, though their catalytic efficiency as well as selectivity was found to be dependent upon the position of amine group to the amide bond. Organocatalyst having –NH2 group ortho to amide bond provided the best results. Substrate scope was also studied by performing the reaction of various β‐nitrostyrenes with ketones to afford the corresponding Michael adducts in excellent yields with very high diastereoselectivities and enantioselectivities in almost all cases.
Zinc Substitution‐Induced Subtle Lattice Distortion Mediates the Active Center of Cobalt Diselenide Electrocatalysts for Enhanced Oxygen Evolution
Authors: Zhang Kai , Zhang Gong , Qu Jiuhui , Liu Huijuan 
Published: February 2020

AbstractDoping engineering has been an important approach to boost oxygen evolution reaction (OER) activity, while investigation on the dopant‐induced modification of active sites and reaction kinetics remains incomplete. Herein, taking the cubic CoSe2 as an example, a universal strategy to synergistically achieve active sites and dynamic regulation is developed by incorporating low‐valence Zn. It is revealed that regulation by Zn can facilitate reconstruction of the surface to form active Co oxyhydroxides under OER conditions. By combining theoretical calculations and characterization by various techniques, it is shown that the incorporation of Zn into CoSe2 can cause subtle lattice distortion and strong electronic interactions, thereby contributing to increased active site exposure and improved OER kinetics. Density functional theory simulations demonstrate that Zn incorporation synergistically optimizes the kinetic energy barrier by promoting co‐adsorption of OER intermediates on a Co site and its adjacent Zn site. As a result, the modified CoSe2 NAs electrode shows optimized catalytic activity and excellent stability with the low overpotential of only 286 mV required to drive a current density of 10 mA cm−2 in an alkaline electrolyte.
Rhynchophylline was exported to cerebral spinal fluid and systemic circulation after intracerebroventricular administration to rats detected by ultra‐high performance liquid chromatography coupled with mass spectrometry
Authors: Xu Xiangting , Luo Shaozhong , Li Meihong , Song Jingfeng , Wang Wei 
Published: February 2020

AbstractAn ultra‐high performance liquid chromatography coupled with mass spectrometry method was developed and validated to determine rhynchophylline in the rat brain and spinal cord, cerebral spinal fluid, and systemic circulation after a single intracerebroventricular administration. The in vivo dynamics of rhynchophylline in rat central nervous system was described through comparison its distribution in systemic circulation. After administration of 100.9 μg/kg 4 h, rhynchophylline 44.6% stayed in brain and spinal cord of 1.2 g, 7.24% in cerebral spinal fluid of 400 μL, and 43.3% in plasma of 8.5 mL, respectively. The mean linearity coefficient was of 0.9995. Accuracy varied from 98.66 to 101.78%, with precision expressed as RSD from 1.15 to 3.13%. The recoveries ranged from 95.78 to 101.92%. This is the first time to present an efficient and effective quantification method for rhynchophylline in the cerebral spinal fluid, brain and spinal cord of rats, which was supposed to have pharmacological effects in the treatment of brain diseases.
Looking for Literacy in All the Right Spaces: The Laundromat
Authors: Neuman Susan B. , Portillo Maya , Celano Donna C. 
Published: February 2020

AbstractUnderresourced communities often have limited access to print and materials to promote children's early literacy development. Recognizing that the neighborhood is a unit of social change, organizations that engage families in early reading and learning with their children, therefore, have increasingly become part of the community landscape. Recently, efforts to promote early literacy have found families in a less conventional place: the local laundromat. The authors report on a study of six laundromats in low‐income communities, three of which were transformed to include literacy‐related play centers and three of which remained business as usual. Results indicated dramatic increases in literacy‐related activity among young children as compared with control sites, demonstrating the potential of these sites to enhance children's opportunity to learn.
Using Texting to Help Families Build Their Children’s Vocabulary at Home
Authors: Snell Emily K. , Wasik Barbara A. , Hindman Annemarie H. 
Published: February 2020

AbstractTexting is increasingly used by teachers to communicate with families about classroom logistics and to support learning at home. The authors review the research evidence supporting texting as a tool for increasing family members’ engagement and their children’s learning, including the authors’ own evidence‐based texting program, Text to Talk, which targets students’ vocabulary development. Finally, the authors offer guidelines to teachers regarding effective texting practices to maximize student learning and family engagement. These guidelines might prove useful to teachers beginning to use texting to facilitate students’ word learning specifically and teachers trying to bridge the home–school gap with other content more generally. The authors’ goal is to share these factors with teachers to help support successful home–school connections.
Preparation and characterization of nano δ‐MnO2‐blended cellulose acetate membrane
Authors: Nu Dang Thi To , Duyen Nguyen Thi My , Linh Nguyen Thi Thuy , Van Hoang Cao , Hung Nguyen Phi 
Published: February 2020

AbstractThe ultrafiltration‐adsorption membrane of nano δ‐MnO2‐blended cellulose acetate was synthesized by physical blending technique via the phase inversion method. The MnO2 nanoparticles were loaded into the cellulose acetate polymer matrix for enhancing adsorption. Particularly, dimethyl sulfoxide, a green solvent was used for membrane fabrication. The prepared membranes were characterized by Fourier transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM) with energy‐dispersive X‐ray spectroscopy (EDX) and element mapping, atomic force microscopy (AFM). The contact angle and water flux were measured for filtration performance of obtained membranes.
Lithium storage performance of SnO2@CMK‐3 composites
Authors: Hang Le Thi Thu , Dung Dang Viet Anh 
Published: February 2020

AbstractSnO2@CMK‐3 composites with different SnO2 contents have been successfully synthesized using incipient wetness technique. Because of a high specific area and porosity, CMK‐3 enables facile penetration of SnCl4 solution inside. Accordingly, SnCl4 clusters confined in the CMK‐3 mesopores easily transform to SnO2 nanoparticles. The obtained SnO2@CMK‐3 composites show a high surface area in a range from 224.8 to 398.1 m2/g and good lithium storage properties. Among the resultant composites, the composite‐70 with 70 % of SnO2 shows the best electrochemical performance. At the rate of C/10, the composite‐70 electrode delivers an average discharge capacity of 678 mAh/g. At high rates such as 5C, and 10C the electrode still achieves a discharge capacity of 270, and 201 mAh/g, respectively. Even after 1000 cycles at the rate of C/2, the electrode maintains 67.8 % of the initial capacity.
Synthesis and characterization of novel poly[4‐phenyl‐3‐(thiophen‐3‐ylmethyl)‐1H‐1,2,4‐triazole‐5(4H)‐thione]
Authors: Trung Vu Quoc , Linh Nguyen Ngoc , Duong Tran Thi Thuy , Chinh Nguyen Thuy , Linh Duong Khanh , Hung Ha Manh , Oanh Doan Thi Yen 
Published: February 2020

AbstractBy the oxidative coupling polymerization, a new polythiophene containing 1,2,4‐triazole heterocyclic group was synthesized in chloroform solvent using iron(III) chloride as an oxidant catalyst. Analyses of infrared (IR) and ultraviolet–visible (UV‐Vis) spectra confirmed that the polymerization reaction took place and the absorption band at 469 nm characterized for π–π* transition in the conjugated polymer. Morphology and surface properties of the polymer were studied by field emission scanning electron microscopy (FESEM). Polymer had relatively uniform size distribution. Based on thermal gravimetry analysis (TGA), polymer is without impurities and has an adequate thermal stability in air atmosphere when completely decomposed at 500 oC. The polymer exhibited fluorescence emissions at 596 nm corresponding to the conjugated chain in polymer. Polymer exhibited a good electrical conductivity in the undoped state (around 1.37E–7 S.cm‐1 at 1 MHz).
Field Chemical Immobilization of Andean and Pampas Cats in the High‐Altitude Andes
Authors: Tellaeche Cintia G. , Reppucci Juan I. , Luengos Vidal Estela M. , Clifford Deana L. , Lucherini Mauro 
Published: February 2020

ABSTRACTThree protocols (Ketamine–Medetomidine, Ketamine–Xylazine and Ketamine–Medetomidine–Midazolam) were used to immobilize 2 sympatric wild cat species, the critically endangered Andean cat (Leopardus jacobita), and the relatively more common Pampas cat (L. colocolo), in the high Andes Mountains of Argentina between September 2011 and May 2016. Based on 8 Andean cat capture events and 9 Pampas cat capture events, we determined that the ketamine–medetomidine combination safely induced 45 minutes of anesthesia at a dosage range of ketamine: 6–9 mg/kg, medetomidine: 0.05–0.08 mg/kg for field immobilization. Heart rate, respiratory rate, and oxygen saturation remained within acceptable limits during all captures, but we had cases of hyperthermia in animals captured during the day. There was no evidence of a decline in the health condition of any animals recaptured 148–1,290 days post–initial capture. © 2020 The Wildlife Society.
Die Rolle des Bergmännischen Verbandes Österreichs
Authors: Mayer Gerhard 
Published: February 2020

ZusammenfassungIn der Zeitspanne von 1997–2020, also seit der Übernahme der Geschäftsführung durch den Autor, ist der Bergmännische Verband Österreichs von einer starken Erweiterung seines Tätigkeitsfeldes und steigenden Mitgliederzahlen gekennzeichnet. Die Struktur der Organisation des BVÖ und seine Aktivitäten auf technisch-wissenschaftlichem und wirtschaftlichem Gebiet werden erläutert, die Beziehungen zu nationalen Behörden und Einrichtungen dargestellt. Die Entwicklung des Verbandes geht angesichts der aktuellen Probleme der Sicherung der Mineralstoffgewinnung und -versorgung in Richtung verstärkter Zusammenarbeit mit Universitäten und Institutionen im europäischen Raum und darüber hinaus.
A polyhedral study of event-based models for the resource-constrained project scheduling problem
Authors: Tesch Alexander 
Published: February 2020

AbstractIn this paper, we study event-based mixed-integer programming (MIP) formulations for the resource-constrained project scheduling problem (RCPSP) that represent an alternative to the more common time-indexed model (DDT) (Pritsker et al. in Manag Sci 16(1):93–108, 1969; Christofides et al. in Eur J Oper Res 29(3):262–273, 1987) for the case when the scheduling horizon is large. In contrast to time-indexed models, the size of event-based models does not depend on the time horizon. For two event-based models OOE and SEE introduced by Koné et al. (Comput Oper Res 38(1):3–13, 2011), we first present new valid inequalities that strengthen the original formulation. Furthermore, we state a new event-based model, the Interval Event-Based Model (IEE), and deduce natural linear transformations between all three models. Those transformations yield the strict domination order $$IEE \succ SEE \succ OOE$$IEE≻SEE≻OOE for their respective linear programming relaxations, meaning that the new IEE model has the strongest linear relaxation among all known event-based models. In addition, we show that DDT can be retrieved from IEE by subsequent expansion and projection of the underlying solution space. This yields a unified polyhedral view on a complete branch of MIP models for the RCPSP. Finally, we also compare the computational performance between all models on common test instances of the PSPLIB (Kolisch and Sprecher in Eur J Oper Res 96(1):205–216, 1997).
Effect of Heat Treatment on Microstructure of Al4Cu-SiC Composites Consolidated by Powder Metallurgy Technique
Authors: Wąsik A. , Leszczyńska-Madej B. , Madej M. , Goły M. 
Published: February 2020

AbstractSilicon carbide particles-reinforced Al4Cu composites containing 2.5, 5 and 7.5 wt.% of reinforcement were fabricated using powder metallurgy (PM) technique. The sintered Al4Cu-SiC composites were solution treated for 6 h at two different temperatures (495 and 530 °C) and then aged at 180 °C for various aging periods (4, 12 and 24 h). Effects of heat treatment on the microstructural changes and microhardness were investigated by scanning electron microscope, transmission electron microscope, x-ray diffraction and microhardness tests. The results indicate the ceramic particles-reinforced Al4Cu matrix requires different heat treatment parameters compared to the unreinforced alloy. The applied solution temperature did not allow for thorough dissolution of alloy phases in the matrix material produced by PM route. However, in Al4Cu-SiC composites the main strengthening phase (Al2Cu) was uniformly distributed in the matrix. The solid-solution temperature increase affects the reduction in time to reach peak hardness. The highest increment in microhardness by aging treatment was observed for composite with the addition of 5 wt.% of SiC solution treated at 530 °C for 12 h (110 HV0.05).
Diagnosis of cerebral microbleed via VGG and extreme learning machine trained by Gaussian map bat algorithm
Authors: Lu Siyuan , Xia Kaijian , Wang Shui-Hua 
Published: February 2020

AbstractCerebral microbleed (CMB) is a serious public health concern. It is associated with dementia, which can be detected with brain magnetic resonance image (MRI). CMBs often appear as tiny round dots on MRIs, and they can be spotted anywhere over brain. Therefore, manual inspection is tedious and lengthy, and the results are often short in reproducible. In this paper, a novel automatic CMB diagnosis method was proposed based on deep learning and optimization algorithms, which used the brain MRI as the input and output the diagnosis results as CMB and non-CMB. Firstly, sliding window processing was employed to generate the dataset from brain MRIs. Then, a pre-trained VGG was employed to obtain the image features from the dataset. Finally, an ELM was trained by Gaussian-map bat algorithm (GBA) for identification. Results showed that the proposed method VGG-ELM-GBA provided better generalization performance than several state-of-the-art approaches.
High strength metallurgical graphene as an additional reinforcing phase for carbon fibre composites
Authors: Kunikowska A. , Szymanski W. , Jedrzejczak A. , Lipa S. , Galazka M. , Szlachetka M. , Kula P. 
Published: February 2020

AbstractThe main objective of the present study is an elaboration of a method for a transfer of high strength metallurgical graphene (HSMG) and its introduction into the structure of fibre laminates. In this work, two transfer procedures have been established: a transfer onto structural adhesive film (SAF) and a direct transfer onto two types of carbon fibre pre-impregnates (uniaxial and biaxial cloth). An important novelty of the presented experimental work is a use of scanning electron microscopy (SEM) operating in the absorbed electrons (AE) mode. This technique enables the evaluation of graphene continuity on a large area within a relatively short time. The SEM/AE technique made it possible to ascertain that the transferred graphene was characterised by a low level of defects, indicating that it could be used as a reinforcing phase in composites. Both transfer procedures, one onto SAF and the other directly onto the pre-impregnates were used for manufacturing flat laminates as well as tubular profiles. The flat samples, containing 0.68 ppm HSMG by weight, exhibited a 9% increase of low cycle fatigue strength. The tubular profiles (bicycle components) with approximately 0.22 ppm of HSMG exhibited a significant increase of fatigue wear during initial tests. In addition, no fatigue delamination was observed at interfaces between the pre-impregnates separated with HSMG graphene.
The potential of SLM technology for processing magnesium alloys in aerospace industry
Authors: Kurzynowski T. , Pawlak A. , Smolina I. 
Published: February 2020

AbstractSelective Laser Melting (SLM) of magnesium alloys is the technology undergoing dynamic development in many research centres. The results are promising and make it possible to manufacture defect-free material with better properties than those offered by the manufacturing technologies used to date. This review aims to evaluate present state as well as main challenges of using Laser Powder Bed Fusion (L-PBF) for processing magnesium alloys as an alternative way to conventional technologies to manufacture parts in the aerospace industry. This literature review is the first one to outline information concerning the potential to use magnesium alloys in the aerospace industry as well as to summarise the results of magnesium alloy processing using AM technologies, in particular L-PBF. The available literature was reviewed to gather information about: the use of magnesium alloys in the aerospace industry—the benefits and limitations of using magnesium and its alloys, examples of applications using new processing methods to manufacture aerospace parts, the benefits and potential of using L-PBF to process metallic materials, examples of the use of L-PBF to manufacture aerospace parts, and state-of-the-art research into L-PBF processing of magnesium and magnesium alloys.
The Progressive Failure Analysis of Uni-Directional Fibre Reinforced Composite Laminates
Authors: Yi T. 
Published: February 2020

ABSTRACTThe three dimensional standard damage model developed by Lavedeze et.al [9, 13] for uni-directional fibre reinforced ply is implemented into the nonlinear solution of NX Nastran within composite solid element to analyze the progressive damage process and ultimate failure of fibre reinforced composite laminates. This ply level meso-damage-constitutive-model takes into account main damage mechanisms including fibre breaking, matrix transverse cracking, and fibre/matrix de-bonding; also considers contributions like plasticity coupling, damage delay effects, and elastic nonlinearity in fibre compression. Dissipated energy and damage status are also introduced to reflect the damage condition on the macrostructural-level. Using the implemented code, simulation is carried out on the uniaxial tension of a [±45]2s laminate with IM6/914 material, wherein the predicted ply shear rupture stress matches the experimental results very well and better than the theoretical predictions in literature. Moreover, a [-45/0/45/90] holed laminate loaded in tension is simulated to show the complex behavior of subcritical damage evolution and failure process in the composite structure. The composite solid element with damage model supported in NX Nastran is shown to be a reliable tool to analyze the progressive failure of uni-directional fibre reinforced composite laminates.