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A dynamic adsorption-migration-photocatalysis-desorption occur on MOC surface for HCHO degradation. The phase 5 in MOC materials adsorb pollutant gas. HCHO molecules migrated to active sites in the catalyst along nano-needle [...]

ABSTRACT The poor water-resistance mechanism of magnesium oxychloride cement (MOC) is well understood in the past decades due to cations and anions in the hydration products. It is difficult to [...]

ABSTRACT Heat curing accelerates cement hydration, leading to a coarse pore structure. This undermines the transport properties of concrete, which is essential in evaluating concrete durability. In this study, effect [...]

ABSTRACT To improve the photocatalytic performance and utilization of Ti[O.sub.2] particles in cementitious materials, this work investigated and differentiated the influences of cement substrate pore structure and Ti[O.sub.2] particles loading [...]

ABSTRACT This study investigated the strategy of using zeolite fly ash bead (ZFAB) as a carrier of Ti[O.sub.2] photocatalyst to improve the photocatalytic efficiency and long-term performance of photocatalytic cementitious [...]

ABSTRACT In this work, photocatalytic cement was prepared by loading [Bi.sub.2]W[O.sub.6] microspheres with Portland cement. 3D hierarchical [Bi.sub.2]W[O.sub.6] microspheres were synthesized by self-assembly of 2D nanosheets and nanoplates firstly. Interestingly, [...]

Drawing upon social exchange theory, this research tests a unique underlying mechanism – interpersonal justice– through which coworker incivility indirectly influenced knowledge sharing (Study 1 and Study 2) as well as communion striving as the moderator of this indirect effect (Study 2). Specifically, Study 1, using cross-sectional data from 272 Chinese employees, and Study 2, using three-wave data from 234 American employees recruited from TurkPrime, confirmed the mediation effect of interpersonal justice (while controlling frustration) on the relationship between coworker incivility and knowledge sharing. Further, Study 2 found that communion striving moderated the relationship between coworker incivility and interpersonal justice such that the negative relationship was stronger for employees with low than high communion striving. Finally, the results of the moderated mediation analyses further supported that the indirect effect of coworker incivility on knowledge sharing via interpersonal justice was stronger among employees with low than high communion striving. This research provides the first empirical evidence of interpersonal justice as the underlying mechanism through which coworker incivility influences employees’ knowledge sharing and how communion striving moderates this mediating mechanism, offering new insights into why and when coworker incivility hinders knowledge sharing. Theoretical and practical implications were discussed.

Locally repairable codes (LRCs), which can recover any symbol of a codeword by reading only a small number of other symbols, have been widely used in real-world distributed storage systems, such as Microsoft Azure Storage and Ceph Storage Cluster. Since binary linear LRCs can significantly reduce coding and decoding complexity, constructions of binary LRCs are of particular interest. The aim of this paper is to construct dimensional optimal binary LRCs with disjoint local repair groups. We introduce a method to connect intersection subspaces with binary LRCs and construct dimensional optimal binary linear LRCs with locality 2b(b≽ 3) and minimum distance d≽ 6 by employing intersection subspaces deduced from the direct sum. This method will sufficiently increase the number of possible repair groups of dimensional optimal LRCs, thus efficiently expanding the range of the construction parameters while keeping the largest code rates compared with all known binary linear LRCs with minimum distance d≽ 6 and locality 2b.

A functionalized polyacrylonitrile fiber PANODF modified by ethanolamine and dithizone is successfully prepared to selectively identify Ag+ by colorimetric method and then reduce various dyes in situ cooperating with NaBH4. The color of functionalized fiber changes from orange to bright red when it is soaked in solution with Ag+ ions. It's even more satisfying that no relevant color change of the fiber has been observed in the solution of other 12 kinds of metal ions. Obvious color change can occur within 3 min and the detection limit can reach 1 ppm for Ag+. In addition, the process of recognizing Ag+will not be interfered by other ions in the real water sample. Moreover, the functionalized fiber can be reused up to 10 times for Ag+recognition. Additionally, the Ag+ ions absorbed on the fiber can be reduced to Ag0, creating a new fiber (PANOD-Ag0F) that can be used as a catalyst to reduce various dyes in situ with NaBH4. The experimental results show that the six kinds of dyes can be quickly reduced to the colorless and less-toxic substance under the condition of NaBH4as the reducing agent and PANOD-Ag0F as the catalyst. The catalytic reduction capacity of PANOD-Ag0F can still reach more than 99 % when it is recycled for 10 times, which proves the practical application potential of the functionalized fiber.

Previous research suggests that workplace deviance, one of the most pressing problems for today’s organizations, tends to decline as employees age. However, little is known about the mechanisms underlying the age-deviance relationship. Using aggregated 5-day daily diary data in a sample of 158 Chinese full-time employees, the present study examined age differences in the use of emotional labor strategies (i.e., surface acting and deep acting) and how these age differences relate to employee workplace deviance via organizational cynicism. Results found that age was negatively related to the use of both surface acting and deep acting. Emotional labor strategies (i.e., surface acting and deep acting) and organizational cynicism serially mediated the relationship between employee age and workplace deviance. The current research deepens our understanding of the processby which employee age relates to workplace deviance. This study also has implications for the management of an increasingly age-diverse workforce and can guide future interventions aiming at reducing workplace deviance, an issue of increasing concern to both organizations and society in general.

Six kinds of 1,3,4-oxadiazole-functionalized fibers were prepared to evaluate the adsorption capacity for Hg2+. Finally, a functionalized fiber (PANp-PMODF) with the best adsorption performance was selected for further research. The PANp-PMODF fiber was characterized by infrared (IR), elemental analysis (EA), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The PANp-PMODF shows excellent selectivity for mercury ions in a mixed heavy metal ion solution (Hg2+, Ni2+, Pb2+, Zn2+, Ag+, Co2+, Cr3+, Cu2+, and Cd2+), and it can reduce the concentration of Hg2+to 44 ppb in the actual sewage, which is of great practical value for the treatment of mercury pollution. Furthermore, the adsorbed Hg2+can be desorbed completely by dilute HNO3and the PANp-PMODF can be reused many times with excellent recyclability.

A series of quaternary ammonium-based (QAB) functionalized polyacrylonitrile fibers as superbase catalysts for C—C bond forming reactions in water were prepared. Alkyl with different chain lengths and benzyl were used to tune the hydrophobicity/hydrophilicity and polarity of the inner surface microenvironment of the QAB functionalized fiber catalysts, and the different microenvironment and the active site synergistically promote the completion of the reaction. The mechanism of the influence of different hydrophilic/hydrophobic catalysts on catalytic activity was proposed. The quaternary ammonium-based functionalized fibers with eight carbon alkyl chains (PANQAB-8F) as the optimal catalyst performed excellently in green water solvent with specific advantages of low catalyst dosage, mild conditions, high efficiency, and extensive substrate adaptation. Furthermore, the PANQAB-8F catalyst is very suitable for the continuous flow process, and more than 86% yield was obtained even after the continuous reaction for 160 h; the fiber can be recovered easily and recycled more than 10 times in the continuous-flow system.

Work hardening is a common method of strengthening copper-based alloys. However, softening behavior is observed in Cu–Cr–Ti–Si alloy during cold rolling processes. Cold deformation greater than 85% can induce softening behavior. We used an electron backscatter diffraction system, X-ray diffraction, and transmission electron microscopy to analyze the microstructure of alloy samples subjected to different degrees of cold deformation. A greater proportion of high-angle grain boundaries, a lower dislocation density, and certain dislocation configurations indicated that the recovery takes place during heavy cold deformation leading to softening phenomenon.

Two sulphur-containing 4-aminonaphthalimide derivatives were investigated as Hg2+fluorescent chemosensors. In CH3CN, both sensors present a remarkable fluorescence enhancement to Cu2+and Fe3+, but a selective fluorescence quenching to Hg2+among the other metal ions. A cation-πinteraction between Hg2+and the naphthalimide moiety was proposed and confirmed by the density functional theory(DFT).

Novel multiarm star copolymers with poly(ε‐caprolactone) (PCL) as the arms and hyperbranched polyethylenimine (HPEI) as the core have been successfully prepared by the tin(II) 2‐ethylhexanoate catalyzed ring‐opening polymerization of ε‐caprolactone (CL) with HPEI used directly as a macroinitiator. Not only primary but also secondary amine groups of HPEI participate in initiating the ring‐opening polymerization of CL with almost 100% initiation efficiency. The average degree of polymerization of the PCL arms can be controlled by the feed ratio of the monomers to the initiating sites. Because of the polarity difference of the PCL arms and HPEI core, the obtained multiarm star polymers display an inverted micellar structure with potential extraction and encapsulation of water‐soluble guests. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4165–4173, 2006

Water electrolysis is considered as one promising strategy for hydrogen production, and thus, preparing electrocatalysts of superior efficiency and low cost for a hydrogen evolution reaction (HER) in a wide pH range is of paramount importance. In this research, N-doped porous carbon nanofibers derived from silk fibroin by KCl chemical activation are successfully synthesized as the metal-free catalyst for the HER under both acidic and alkaline conditions. After chemical activation of KCl, hierarchical porous structures are formed. Besides, it is found that the concentration of KCl in the electrospun membrane will affect the maintenance of the fibrous morphology for the carbonized samples due to the destruction of β-sheets in silk fibroin induced by KCl. The specific surface area of the optimized sample, 4%-SPCNF, increased by nearly nine times compared with that without activation because of the hierarchical pores and large through pores between fibers. Meanwhile, the porosity increases from 59.87 to 80.28% due to the existence of through pores. Moreover, the 4%-SPCNF has remarkable stability and durability since the carbon substrate is resistant against the corrosion of the electrolyte. Our work provides insights into the design and engineering of silk fibroin-derived carbon nanofibers for metal-free catalysts of the HER under acidic and alkaline conditions.

Developing electrocatalysts with high efficiency and long-term stability for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is significant to massively generate hydrogen energy by water splitting. In this work, cobalt and tungsten dual metal-loaded N-doped porous carbon electrocatalysts derived from silk fibroin were successfully prepared through facile carbonization and chemical activation by KCl and applied as efficient electrocatalysts for HER and OER. After chemical activation, the resulting catalysts present a unique hierarchical porous structure with micro-, meso-, and macropores, which is able to expose more implantation sites for catalytic active metals and will in turn promote the efficient diffusion of the electrolyte. The catalyst under the optimized condition (CoW@ACSF) has a specific area of 326.01 m2g–1. The overpotential at a current density of 10 mA cm –2of CoW@ACSF is 138.42 ± 10.39 mV toward HER and 492.05 ± 19.04 mV toward OER. Furthermore, the overpotential only increases 101.2 mV toward HER and 66.00 mV toward OER after the long-term stability test of chronopotentiometric test over 10 h, which confirms the excellent stability of the CoW@ACSF, owing to its unique carbon shell structure. This work gives an insight into the design and engineering of silk fibroin-derived carbon materials for electrocatalysis toward HER and OER.

The issues of chemical doping effects on cement clinker properties have long been investigated but are not fully understood. This work aims to provide an atomic-level understanding of the essential relations between clinker reactivity and its electronic structure and clarify the mechanism of doping effect on clinker reactivity. The Fukui functions reveal that zinc doping reduces the number of reactive sites and effective charges of silicate and aluminate phases dramatically, which accounts for the significant hydration retardation as observed in previous experiments. However, Zn doping scarcely changes the number of reactive sites but increases the effective charges and the total localization index of the ferrite phase due to the strong localization capacity of Fe 3dstates, which implies a slight reactivity promotion. The comprehensive and in-depth methodology demonstrated in this paper is significant to facilitate the innovation of cementitious materials with desirable properties.

The amount of Zn reagent is optimized to produce the desired aldehydes (nearly) exclusively.

The catalyst is prepared by aminating polyacrylonitrile fiber with N,N‐dimethyl‐1,3‐propanediamine.

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