bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pure and mixed gas permeation study of silica incorporated polyurethane‐urea membrane modified by MOCA chain extender
Authors: Babaei Shahryar , Nematollahi Mohammad Hadi , Abedini Reza 
Published: February 2020

AbstractPolyurethane‐urea (PUU) nanocomposite membranes have been prepared using various loadings of silica (SiO2) nanoparticles. A Novel PU was fabricated by a two‐step bulk polymerization technique based on polycaprolactone (PCL), hexamethylene diisocyanate (HDI), and diamine chain extender, 4,4‐methylenebis(2‐chloroaniline) (MOCA). The FTIR spectra indicated that the extent of phase separation reduces with increasing SiO2 content. The presence of crystal regions in the soft and hard segments was confirmed by DSC and XRD analyses. The obtained results illustrated a decrement in the gases' permeation in the presence of SiO2 particles. By increasing the filler content up to 15 wt% and pressure of 8 bar, the gas permeation value of the CO2, O2, and N2 decreased 36%, 54%, and 59%, respectively. However, the permselectivity of the CO2/N2 and O2/N2 increased considerably, 55% and 13% respectively. On the contrary, by raising the temperature, a dramatic augmentation in the permeability of all gases with a simultaneous reduction in the selectivity values of both gas pairs was revealed. Increasing the pressure led to a decrease in the permeability values of all membranes for O2 and N2, whereas the permeability for CO2 increased with the pressure. Nevertheless, the selectivity values for the pair of gases increased (at a pressure of 10 bar, 1.66 and 1.17 times the neat PU for CO2/N2 and O2/N2, respectively). Furthermore, the permeability of the CO2, O2, and N2 for the mixed gases was smaller than for pure ones at the same gas upstream pressure. Nonetheless, like the pure gas, the selectivity of both pair gases increased.
Retracted: Corporate social responsibility, work meaningfulness, and employee engagement: The joint moderating effects of incremental moral belief and moral identity centrality
Authors: Afsar Bilal , Al‐Ghazali Basheer , Umrani Waheed 
Published: February 2020

AbstractThis study investigated the mediating role of work meaningfulness on the relationship between employees' perception about organization's corporate social responsibility (CSR) practices and their engagement. Moreover, the joint moderating effects of incremental moral belief and moral identity centrality were also tested. Utilizing survey‐based data, this study analyzed the responses of 622 employees working in various industries. Results showed that incremental morality beliefs strengthened the effect of CSR perceptions on work meaningfulness, especially when moral identity centrality was weaker. Specifically, CSR perceptions had the strongest positive effect on work meaningfulness among employees with stronger incremental morality beliefs and weaker moral identity centrality. Another interesting finding of this study was that incremental morality beliefs strengthened the effect of CSR perception on employee engagement via work meaningfulness, especially when moral identity centrality was lower. This study found that CSR perceptions had the strongest positive effect on employee engagement via work meaningfulness among employees with stronger incremental morality beliefs and weaker moral identity centrality. The findings confirmed that incremental morality beliefs and moral identity centrality jointly moderated these relationships.
Foraging niche shift maintains breeding parameters of a colonial waterbird during range expansion
Authors: Francesiaz Charlotte , Yohannes Elizabeth , Besnard Aurélien , Sadoul Nicolas , Blanchon Thomas , Béchet Arnaud 
Published: February 2020

AbstractRelating the effects of foraging niche variation to reproductive dynamics is critical to understand species response to environmental change. We examined foraging niche variations of the slender‐billed gull (Chroicocephalus genei), a nomadic colonial waterbird species during its range expansion along the French Mediterranean coast over a 16‐year period (1998–2013). We investigated whether range expansion was associated with a change in chick diet, breeding success, and chicks body condition. We also examined whether breeding success and chicks body condition were explained by diet and colonial characteristics (number of pairs, laying phenology, habitat, and locality). Diet was characterized using dual‐stable isotopic proxies (δ13C and δ15N) of feather keratin from 331 individuals subsampled from a total of 4,154 chicks ringed and measured at 18 different colonies. δ13C decreased and δ15N increased significantly during range expansion suggesting that chicks were fed from preys of increasing trophic level found in the less salty habitat colonized by the end of the study period. Niche shift occurred without significant change of niche width which did not vary among periods, habitats, or localities either. Breeding success and chick body condition showed no consistent trends over years. Breeding success tended to increase with decreasing δ13C at the colony level while there was no relationship between stable isotope signatures and chick body condition. Overall, our results suggest that even if range expansion is associated with foraging niche shift toward the colonization of less salty and more brackish habitats, the shift had marginal effect on the breeding parameters of the Slender‐billed gull. Niche width appears as an asset of this species, which likely explains its ability to rapidly colonize new locations.
Annihilating the Formation of Silicon Carbide: Molten Salt Electrolysis of Carbon–Silica Composite to Prepare the Carbon–Silicon Hybrid for Lithium‐Ion Battery Anode
Authors: Zhou Xianbo , Xie Hongwei , He Xiao , Zhao Zhuqing , Ma Qiang , Cai Muya , Yin Huayi 
Published: February 2020

Silicon (Si) and carbon (C) composites hold the promise for replacing the commercial graphite anode, thus increasing the energy density of lithium‐ion batteries (LIBs). To mitigate the formation of SiC, this paper reports a molten salt electrolysis approach to prepare C‐Si composite by the electrolysis of C‐SiO2 composites. Unlike the conventional way of making a C coating on Si, C‐SiO2 composites were prepared by pyrolyzing the low‐cost sucrose and silica. The electrochemical deoxidation of the C‐SiO2 composites not only produces nanostructured Si inside the C matrix but also introduces voids between the C and Si owing to the volume shrinkage from converting SiO2 to Si. More importantly, the use of Mg ion‐containing molten salts precludes the generation of SiC, and the electrolytic Si@C composite anode delivers a capacity of about 1500 mAh g−1 after 100 cycles at a current density of 500 mA g−1. Further, the Si@C|| LiNi0.6Co0.2Mn0.2O2 full cell delivers a high energy density of 608 Wh kg−1. Overall, the molten salt approach provides a one‐step electrochemical way to convert oxides@C to metals@C functional materials.
Exploring the relationship between umbilical blood cord donation and the impact of social distance on altruism and trust
Authors: Panasiti Maria Serena , Violani Cristiano , Grano Caterina 
Published: February 2020

Allogeneic umbilical cord blood (UCB) donation is a pro‐social behaviour directed to strangers that has a certain cost for the donor. Although the promotion of such behaviour is an important goal for many countries' health systems, little is known about the reasons that would lead to it. With this study, we explored how the impact of social closeness on altruism and trust could be related to UCB donation in a sample of new‐mothers (N = 167). Participants played hypothetical Dictator and Trust games with socially close (e.g., parents) or distant (e.g., strangers) others. They donated more money to parents and siblings compared to cousins, friends and strangers and they trusted more parents, siblings and friends than cousins and strangers. Interestingly, the lower the impact of social closeness on altruism (i.e., generosity towards socially distant others), the higher the intention and the actual probability of UCB donation. A mediation analysis has shown that the relationship between social closeness on altruism and UCB donation was mediated by objective intention to donate (i.e., having followed all the procedures needed). These findings show that other‐oriented motivations towards distant others might have important practical implications in identifying the targets of interventions for the promotion of UCB donation.
Common correlated effects estimation of heterogeneous dynamic panel quantile regression models
Authors: Harding Matthew , Lamarche Carlos , Pesaran M. Hashem 
Published: February 2020

SummaryThis paper proposes a quantile regression estimator for a heterogeneous panel model with lagged dependent variables and interactive effects. The paper adopts the Common Correlated Effects (CCE) approach proposed in the literature and demonstrates that the extension to the estimation of dynamic quantile regression models is feasible under similar conditions to the ones used in the literature. The new quantile regression estimator is shown to be consistent and its asymptotic distribution is derived. Monte Carlo studies are carried out to study the small sample behavior of the proposed approach. The evidence shows that the estimator can significantly improve on the performance of existing estimators as long as the time series dimension of the panel is large. We present an application to the evaluation of Time‐of‐Use pricing using a large randomized control trial.
3‐Hydroxypicolinic Acid as an Effective Matrix for Sophorolipid Structural Elucidation Using Matrix‐Assisted Laser Desorption Ionization Time‐of‐Flight Mass Spectrometry
Authors: Yatim Abdul Rashid M. , Wan Muhammad Zulkifli Wan Nur Fatihah , Majid Amin Malik Shah , Foster John L. , Hayes Douglas G. 
Published: February 2020

AbstractDetermination of the distribution of sophorolipid (SL) congeners controls their self‐assembly structures and therefore their employment as glycolipid biosurfactants in cosmetics, environmental remediation, and personal care applications. The compatibility of 3‐hydroxypicolinic acid (HPA) as a matrix for compositional analysis of SL using palm olein as carbon energy source by matrix‐assisted laser desorption ionization time of flight mass spectrometry (MALDI‐TOF MS) analysis under positive and negative ion modes is studied in this work. Examination in positive ion mode revealed ions that were not detected in negative ion mode. Molecular ions produced using HPA matrix were lactonic Glc‐Glc‐1′,4″‐C18:1, anionic Glc‐Glc‐1′‐C18:1, lactonic monoacetate of Glc‐Glc‐1′,4″‐C18:1, and anionic monoacetate Glc‐Glc‐1′‐C18:1 and the anionic diacetate of Glc‐Glc‐1′‐C18:1. We also detected Glc‐Glc‐1′‐C18:0, GlcOAc‐Glc‐1′‐C18:0, GlcOAc‐GlcOAc‐1′,4″‐C18:0, and GlcOAc—GlcOAc‐1′‐C18:0 which are congeners of SL with stearic acid moieties. 3‐HPA has been established to be the superior matrix for elucidation of structures for SL using MALDI‐TOF MS.
Dissolution optimization and kinetics of nickel and cobalt from iron‐rich laterite ore, using sulfuric acid at atmospheric pressure
Authors: Hosseini Nasab Marzieh , Noaparast Mohammad , Abdollahi Hadi 
Published: February 2020

AbstractMore than 70% of the world's nickel reserves are found in laterite ores. In this research, a laterite ore sample, containing Ni, Co, and Fe, was employed to study the recovery of nickel and cobalt. Thus, the effect of calcination, acid concentration, percent solids, and stirring rate on nickel and cobalt recoveries from an iron‐rich laterite sample was investigated. Optimization with response surface methodology and kinetic studies were performed. The calcination of the sample prior to leaching at 500°C for 2 h provided condition for better nickel and cobalt dissolutions. At optimal conditions, the concentration of sulfuric acid, solid‐to‐liquid ratio, stirring speed, temperature, and time test were equal to 5 M, 0.1, 370 rpm, 90°C, and 2 h, respectively. The highest recoveries of nickel and cobalt were 65.9% and 63.1%, respectively. Solids content had a negative effect on Ni and Co recovery, whereas acid concentration was positively affected. Addition of 10% (w/v) NaCl in the presence of 5 M acid concentration, 60°C, 370 rpm, and leaching time of 2 h increased the nickel and cobalt recoveries, 15.3% and 21.4%, respectively. The high dependence of process on temperature indicates chemical control; the activation energies Ea = 59.54 and Ea = 45.74 kJ/mol, respectively, for nickel and cobalt, were also consistent with this conclusion.
Feasible Preparation of a Thin‐Film Composite Nanofiltration (TFC NF) Membrane with Enhanced Skin–Substrate Adhesion and Compaction Resistance: In Situ Construction of Rigid–Flexible Polymer Composited Microspheres (CPs) in the Casting Solution
Authors: Lian Xiangyang , Xie Jianqiang , Shi Qiang , Liu Wanjun , Yao Shaowei , Sun Xiufang 
Published: February 2020

AbstractNovel microspheres (CPs) composited by rigid and flexible polymers are synthesized and embedded in the supporting membranes to enhance both the skin–substrate adhesion and compaction resistance of the thin‐film composite (TFC) nanofiltration membranes. The CPs are in situ formed in the casting solution after the rigid poly(p‐phenylene terephthamide) (PPTA) is produced in the flexible poly(m‐phenylene isophthalamide) (PMIA) solution. Then the PPTA/PMIA in situ blending membranes are prepared by using the NIPs method, and the TFC NF membranes are fabricated via interfacial polymerization on them. The CPs are characterized via polarizing microscopy and TEM. The surface morphology and chemical composition of the blended membranes are characterized by using FESEM, AFM, FTIR, and WCA, respectively. As the results show, the supporting membrane with higher PPTA content exhibits higher permeability, thermal stability, and compaction resistance. Moreover, the adhesion strength between the TFC functional layer and the supporting membrane is improved significantly. It is proposed that this improvement can be attributed to the CPs that are exposed on the top surface of the supporting membrane, which leads to a great enhancement because of the anchoring effect between the functional layer and the CPs.
HEMA‐Modified Expandable P(MMA‐AA) Bone Cement with Dual Water Absorption Networks
Authors: Chen Lei , Tang Yufei , Zhao Kang , Liu Jiaxin , Jiao Mengzhen , Bai Hao , Wu Zixiang 
Published: February 2020

AbstractAlthough the shrinkage of polymethyl methacrylate (PMMA) bone cement has been tackled by the poly(methyl methacrylate‐co‐acrylic acid) [P(MMA‐AA)] bone cement due to the expandable P(MMA‐AA) copolymer in the solid phase, the hydrophobicity of PMMA and its solidification restrict simulated body fluid (SBF) diffusion and expansion properties. In this research, hydroxyethyl methacrylate (HEMA)‐modified P(MMA‐AA) bone cement (HMBC) is obtained by introducing HEMA into the liquid phase of P(MMA‐AA) bone cement. It is assumed that the dual water absorption networks can promote the SBF absorption capacity, thus resulting in the increased expansion behavior. The results demonstrate that the introduction of HEMA improves the hydrophilicity of the bulk. SBF absorption efficiency and swelling efficiency are promoted in the primary step of expansion. The porous structure of HMBC contributes to the increased SBF absorption and swelling in the second step of expansion behavior. Meanwhile, the remarkable absorption ratio and expansion ratio reach 88.5% and 97.4%, respectively. Furthermore, enhanced biocompatibility and osteogenesis activity provide HMBC as a promising biomaterial in the clinical setting.
Simulation and implementation of CMOS 8:1 LC‐tank injection‐locked frequency divider
Authors: Jang Sheng‐Lyang , Ciou You‐Liang 
Published: February 2020

AbstractThis letter simulates and measures a wide locking range LC‐resonator injection‐locked frequency divider (ILFD) designed in the TSMC 0.18 μm process. The balanced‐injection 8:1 ILFD uses a current‐mode design method with one 2:1 p‐core LC sub‐ILFD and one 4:1 n‐core LC sub‐ILFD with wide locking range. The 4:1 sub‐ILFD uses a 5‐turn symmetric octagonal inductor and two 4‐turn inter‐wound transformers and parasitic capacitors to build the LC‐resonator. The primary and the secondary inductors in the 1:1 transformer are identical for simple design. At the core power consumption 9.537 mW and at the incident power of 0 dBm, the measured 8:1 locking range is 1.11 GHz, from the incident frequency 16.83 to 17.94 GHz. The whole CMOS die occupies an area of 0.931 × 1.2 mm2. The simulated 8:1 sub‐ILFD also has wide locking range.
Relationship Between Pubic Symphysis Separation and Postpartum Pelvic Girdle Pain: A Retrospective Study of 32 Cases
Authors: Qiao Jie , Qin Jian , Feng Jing , Huang Mi , Xia Ping 
Published: February 2020

BackgroundPain severity of postpartum pelvic girdle pain (PGP) does not seem closely related to the symphysis gap.ObjectiveTo determine the relationship between the pubic symphysis gap and postpartum PGP in women treated with the squeeze‐and‐clap maneuver.DesignRetrospective study.SettingHospital ClinicPatients32 patients with postpartum PGP.MethodsThe patients were grouped by the pubic symphysis gap as: group A (6–11 mm), group B (12–20 mm), and group C (21–30 mm).Main outcome measurementsGP severity was measured by visual analogue scale (VAS). The symphysis gap was measured on radiographs. All patients were treated with the squeeze‐and‐clap maneuver. The VAS scores and the symphysis gaps at the first clinic visit and the second clinic visit 4–8 weeks later were analyzed.ResultsThere was no significant difference in VAS scores between the three groups at the first clinic visit and the second clinic visit. VAS scores of the three groups were all significantly decreased at the second clinic visit compared with the first clinic visit (all P < .001). The symphysis gap was significantly decreased in group C at the second clinic visit (P = 0.004), but not in group A and group B.ConclusionPubic symphysis separation was not associated with pain severity of postpartum PGP.
Synthesis of polyimides with lower H2O‐absorption and higher thermal properties by incorporation of intramolecular H‐bonding
Authors: Qian Guangtao , Chen Haiquan , Song Guangliang , Yao Jianan , Hu Mengjie , Chen Chunhai 
Published: February 2020

AbstractTo introduce intramolecular hydrogen bonds in the polyimides (PIs), 5(6)‐amino‐2‐(5‐aminopyridin‐2‐yl)‐benzimidazole (PyPABZ) were designed and synthesized. The intramolecular interaction was indicated by Fourier transform infrared when different copolyimides were prepared with 4,4′‐oxydianiline and PyPABZ. These modified poly(benzimidazole imide)s eliminate the problem of high water absorption for benzimidazole (BI)‐containing PIs in the materials applications. Moreover, the high packing coefficient and rigidity of these copolyimides caused by the strong intramolecular interaction from the H‐bonding and the resulting PIs exhibited outstanding thermal properties such as high glass‐transition temperature (Tg) and low coefficient of thermal expansion.
Development of a mapping approach encompassing most fluvial processes: Lessons learned from the freedom space for rivers concept in Quebec (Canada)
Authors: Massé Simon , Demers Sylvio , Besnard Clément , Buffin‐Bélanger Thomas , Biron Pascale M. , Choné Guénolé , Massey William 
Published: February 2020

AbstractThe consensus around the need for a shift in river management approaches to include more natural processes is steadily growing amongst scientists, practitioners, and governmental agencies. The freedom space for rivers concept promotes the delineation of a single space that integrates multiple fluvial dynamics such as floods, lateral migration, channel avulsions, and riparian wetlands connectivity. The objective of this research is to assess the validity of the hydrogeomorphological approach to delineate the freedom space for an extensive sampling of river reaches, covering 167 km, in contrasting watersheds in Quebec (Canada). Comparative analysis was conducted on the relative importance of erosion and flood processes on the freedom space delineation for various fluvial types. Semiautomated tools based on light detection and ranging (LiDAR) digital elevation models were also tested on an additional 274 km of watercourses to facilitate freedom space mapping over extensive zones and for highly dynamics environments such as alluvial fans. In the studied reaches, flood and erosion processes occur respectively, on average, in a space equivalent to 2.6 and 20.6 channel widths. In unconfined landscapes, flood processes represent an area up to almost four times the area of erosion processes expected in a 50‐year period. In partly confined and confined environments, erosion processes are more likely to exceed flooding zone, and therefore need to be integrated in the mapping. This study helps better determine the conditions for which the full methodology of freedom space mapping is required or where semiautomated methods can be used. It provides useful guidelines for the implementation of the freedom space approach.
OSA Esterification of Amaranth and Maize Starch Nanocrystals and Their Use in “Pickering” Emulsions
Authors: Sánchez de la Concha Brenda B. , Agama‐Acevedo Edith , Agurirre‐Cruz Andres , Bello‐Pérez Luis A. , Alvarez‐Ramírez José 
Published: February 2020

AbstractEmulsions are widely used in food, drug, and cosmetic products. Due to their small size, starch nanocrystals are proposed to stabilize Pickering emulsions. However, this application is effective only when starch nanocrystals offer a strong amphipathic character. Waxy maize and amaranth starch nanocrystals are treated chemically with octenyl succinic acid (OSA) to obtain particles which are able to stabilize of oil‐in‐water emulsions. The emulsification capacity of OSA‐treated starch nanocrystals is compared with the capacity offered by non‐treated starch. It is shown that OSA treatment enhanced the emulsification capacity, and the effect is attributed to the increase of repulsive forces as reflected by ζ‐potential. Compared with nanocrystals obtained from waxy maize starch, amaranth exhibits superior emulsification ability, which is preserved under storage conditions. Overall, the results show that OSA‐treated starch nanocrystals are viable alternatives for the stabilization of emulsion systems.
Algebraic expressions for estimating the impact depths of a surface barrier over a homogeneous soil
Authors: Zhang Zhuanfang Fred 
Published: February 2020

AbstractEngineered surface barriers are used to isolate subsurface contaminants for effective long‐term containment of waste of a variety of types. The impact depths of a surface barrier are affected by the pre‐barrier recharge rate and the properties of the soil beneath the barrier. In this paper, algebraic expressions are developed to estimate drainage velocities and barrier impact depths after the emplacement of a surface barrier. Four impact depth terms are used to convey barrier impact: the near‐zero‐, 50%, average‐, and full‐impact depths. The algebraic expressions show that the average‐impact depth is no more than one‐third of the near‐zero‐impact depth, whereas the 50% impact depth is slightly larger than one‐half of the near‐zero‐impact depth. The full‐impact depth, depending on the final recharge rate from the surface barrier, is usually much smaller than the other impact depths. These differences lead to a very large transition zone beneath a surface barrier. A field drainage experiment and a series of numerical simulations were used to test the algebraic expressions. The experimental data and numerical results corroborated the analytical models by predicting very similar water content profiles and/or near‐zero‐, 50%, average‐, and full‐impact depths during the drainage process. The algebraic expressions provided are useful for quickly identifying sites where the depth of the existing contaminants could be beyond the protection of a surface barrier.