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Two solvent-dependent 3D supramolecular architectures, constructed by doubly-interpenetrating layered 2D MOF and triply-interpenetrating 3D MOF, respectively, showed interesting reversible solvent vapor ad-/desorption behaviors.

Flexible transparent conducting coatings have been adopted in many novel optoelectrical devices for energy-related applications. Laminated coatings composed of oxide/metal/oxide (abbreviated as OMO) layers are promising alternative materials to indium tin oxide (ITO). However, the durability and weatherability of free-standing OMO samples—including laminated OMO coatings and polymeric substrates—affects the performance of the related optoelectrical components and devices. It is necessary to study the degradation mechanisms in terms of optoelectrical and mechanical properties through the weathering tests. In this study, we performed indoor accelerated and outdoor weathering tests on commercial OMO samples composed of ZTO/Ag/ZTO coatings on polyethylene terephthalate (PET) substrates. The effects of environmental stressors such as ultraviolet (UV) radiation, elevated temperature, and mechanical bending on the degradation behaviors of OMO samples were investigated. Comprehensive material characterizations including UV–Vis spectroscopy, four-point probing, tensile tests, and Raman spectroscopy were carried out. The OMO coating was robust against the weathering tests, while the PET substrates underwent embrittlement upon long-term weathering. The embrittled PET substrates consequently impaired the mechanical flexibility and bendability of the OMO coatings. The results of this study provide an in-depth understanding of the durability and weatherability of silver-based OMO flexible transparent conductive materials.

The condensation of poly(acrylic acid) (PAA) with small amounts of hyperbranched poly(ethyleneimine) (PEI) resulted in the dual cross-linked network cxPAA-PEI(x) (x: wt % of PEI, x = 1, 3, and 5), ...

The electrochemical sensing applications of a series of water-stable 2D metal–organic framework (MOF)-modified screen-printed carbon electrodes (SPCEs) are reported. The MOF materials in this study are [M(bipy)(C4O4)(H2O)2]·3H2O, in which bipy = 4,4′-bipyridine and M = Mn, Fe, Co and Zn. The MOF materials are characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), showing that the MOFs have a layer-by-layer rod structure with a smooth surface. We use the nitrofurazone molecule as a probe to investigate the influence of the metal ions of MOFs on electrochemical sensing ability. Cyclic voltammetry demonstrated that the Mn-MOF electrode of interest delivered stronger signals than that of other electrodes. Through first-principles calculations, we also revealed that the change in the spin polarization of divalent metal ions passing from the free ion state to the MOF environment appeared to be significantly correlated with the enhancement in the peak response current. The theoretical and experimental results consistently indicate that Mn-MOF has the smallest bandgap and good sensitivity among these MOF materials. Accordingly, we proposed a simple model to illustrate this observation and disclosed the importance of the electron configuration of the transition metal constructing the MOF materials used in improving electrochemical sensing applications.

Two supramolecular architectures, [Mn(Hdpe)(C4O4)0.5(H2O)3][Mn(C4O4)2(H2O)2] (1) and [Mn(Hdpe)2(H2O)4][Mn(C4O4)2(H2O)2]2·8H2O (2) (C4O42– = dianion of squaric acid (H2C4O4); dpe = 1,2-bis(4-pyridyl...

PurposeThe purpose of this study is to understand how ethical leadership and coworker ethical behavior will influence employee unethical pro-organizational behavior (UPB). In particular, the authors examine the mediating effect of moral disengagement on the relationship between ethical leadership and UPB and also investigate the moderating effect of coworker ethical behavior on the aforementioned effect.Design/methodology/approachData were collected from 251 employee–coworker dyads from five organizations in Taiwan at two time points. Moderated mediation analysis was conducted to test the hypotheses.FindingsThe results show that moral disengagement mediates the relationship between ethical leadership and employee UPB. Moreover, the results show that coworker ethical behavior moderates the relationship between moral disengagement and employee UPB, as well as the mediated relationship between ethical leadership and employee UPB via moral disengagement. Specifically, both the moral disengagement–UPB relationship and the ethical leadership–moral disengagement–UPB relationship become weaker when coworker ethical behavior is high.Practical implicationsThe results highlight the importance of creating an ethical work environment to get everyone behaving ethically in the workplace, because nurturing an ethical atmosphere in organizations will be useful in reducing the occurrence of UPB even for those who have high levels of moral disengagement.Originality/valueThis study shows that coworkers matter morally as much as leaders, demonstrating the importance of social influence from coworkers in organizations.

PurposePrevious studies have found that abusive supervision undermines employees' work motivation and attitudes, namely work engagement and job satisfaction. However, less is known about the mechanisms by which abusive supervision negatively relates to employees' work engagement and job satisfaction. Drawing on conservation of resources theory, this study examines employee silence as a mediating mechanism linking abusive supervision to employees' work engagement and job satisfaction.Design/methodology/approachSurvey data were collected from a sample of 233 full-time employees of a large hotel service company in Taiwan. Structural equation modeling analyses were conducted to test the hypotheses.FindingsThe results showed that abusive supervision has a positive association with employee silence. Moreover, the results showed that employee silence mediates the negative associations of abusive supervision with employees' work engagement and job satisfaction.Practical implicationsThe results suggest that organizational managers should provide supervisors with leadership interventions to prevent the occurrence of abusive supervision. Furthermore, organizational managers should provide employees with opportunities to voice their concerns through the use of organizational communication and participation, which can reduce employee silence and subsequently foster employee engagement and satisfaction at work.Originality/valueThis study advances our understanding of how abusive supervision results in poor work motivation and attitudes among employees. This contributes to the literature by identifying employee silence as a suitable mediating mechanism linking the negative associations of abusive supervision with employees' work engagement and job satisfaction.

A SET-state conductance change in a hafnium-oxide resistive switching memory cell due to repeated read events is investigated. We characterize a read-induced conductance change at different read voltages and SET-state conductance levels. Our result shows that the read-induced conductance degradation exhibits a two-stage evolution with the read pulse number. A SET-state conductance decreases slightly in the first stage and then follows inverse power-law dependence on the read number in the second stage. The power factor is an exponential function of a read voltage without regard to the SET-state conductance level, and the read pulse number at the transition of the two stages is related to a read voltage and conductance level. An analytical model to describe the two-stage conductance evolution is proposed. The parameters in the model are extracted from measurement data. Our model is verified by good agreement between the modeled and measured results in a wide range of read pulse number, read voltage, and SET-state conductance level.

One-pot solvothermal reactions of 2-aminopyridine, triethylorthoformate and sodium hydroxide with CuX (X = Br, and I) in dimethylformamide (DMF) and methanol (MeOH) afforded extended metal chains based on the linear tetracopper units, {[Cu4Br2(Dpyf)2]·DMF}n, 1, and [Cu4I2(Dpyf)2]n, 2, which were structurally identified by X-ray crystallography. Complexes 1 and 2 present closed-shell Cu(I)–Cu(I) interactions that are supported by formamidinate ligands, resulting in a face-to-side configuration and a face-to-face configuration, respectively, for the tetranuclear units. Complexes 1 and 2 represent the first example of one-dimensional (1D) coordination polymers that are based on linear tetracopper units. Moreover, complexes 1 and 2 can be regarded as copper(I) halide aggregates with the unique Cu4Br22+ and Cu4I22+ cations extending into a 1D zigzag chain and a looped chain, respectively. Complexes 1 and 2 show broad emissions at 570 and 549 nm, respectively, which can most probably be ascribed to 3d(Cu) → π* metal to ligand charge transfer. Reversible crystal-to-crystal transformation and luminescence change were observed for complex 1 upon solvent exchange, which can be regarded as a potential luminescent sensor for selective detection of water and methanol.

The heterojunction of ZnO was deposited on hydrogenated TiO2 nanotube arrays (H–TiO2) by atomic layer deposition (ALD) with various cycles. The ZnO was uniformly wrapped with the H–TiO2 samples and the thickness could be accurately controlled by the cycle numbers of ALD. The higher growth rate ~2.7 A/cycle was obtained due to the surface amorphous layer, compared with the air-treated samples (A-TiO2), ~2.3 A/cycle. When the cycle numbers increased to 200, nanowire arrays appeared. Interestingly, the absorption in the visible light region improved more significantly when ALD ZnO was employed for the H–TiO2 rather than the A-TiO2 samples. The H–TiO2 samples with 42 nm of ALD ZnO exhibited enhanced photoelectrochemical water splitting performances, compared with the A-TiO2 with 42 nm of ALD ZnO. This was related to the higher degree of the electronic band bending and improved photo-response in the UV and visible light region, resulting from the oxygen vacancies.

The electrochemical sensing applications of a series of water-stable 2D metal-organic framework (MOF)-modified screen-printed carbon electrodes (SPCEs) are reported. The MOF materials in this study are [M(bipy)(C

A three-dimensional (3D) polycatenation supramolecular network with chemical formulas, [Zn(bpp)(BDC)]·1.5H2O (1), (bpp = 1,3-bis(4-pyridyl)propane, BDC2- = dianion of terephthalic acid), was synthesized and structurally determined. In compound 1, the coordination geometry of Zn(II) ion is distorted tetrahedral, where its 2D undulated layered framework is constructed via the bridges of Zn(II) ions with bpp and BDC2− ligands. Adjacent 2D layers are arranged in a combined parallel and interpenetrated manner to complete its 3D polycatenation supramolecular architecture. Compound 1 shows a one-step dehydration process with the weight losses of 6.1 %, approximately equal to the weight percentage of losing 1.5 guest water molecules. The cyclic thermogravimetric analysis reveals that compound 1 shows reversible, sponge-like water de-/adsorption behavior during de-/rehydration processes. Compound 1 also exhibits significant water vapor hysteresis isotherm.

Post tetanic potentiation (PTP) is a form of short-term plasticity that lasts for tens of seconds following a burst of presynaptic activity. It has been proposed that PTP arises from protein kinase C (PKC) phosphorylation of Munc18-1, an SM (Sec1/Munc-18 like) family protein that is essential for release. To test this model, we made a knockin mouse in which all Munc18-1 PKC phosphorylation sites were eliminated through serine-to-alanine point mutations (Munc18-1 SA mice). Expression of Munc18-1 was not altered in Munc18-1SA mice, and there were no obvious behavioral phenotypes. At the hippocampal CA3 to CA1 synapse, and the granule cell parallel fiber to Purkinje cell (PF to PC) synapse, basal transmission was largely normal except for small decreases in paired-pulse facilitation that are consistent with a slight elevation in release probability. Phorbol esters that mimic activation of PKC by diacylglycerol still increased synaptic transmission in Munc18-1 SA mice. In Munc18-1 SA mice, 70% of PTP remained at CA3 to CA1 synapses, and the amplitude of PTP was not reduced at PF to PC synapses. These findings indicate that at both CA3 to CA1 and PF to PC synapses, phorbol esters and PTP enhance synaptic transmission primarily by mechanisms that are independent of PKC phosphorylation of Munc18-1.Significance StatementA leading mechanism for a prevalent form of short-term plasticity, post-tetanic potentiation (PTP), involves protein kinase C phosphorylation of Munc18-1. This study tests this mechanism by creating a knock in mouse in which Munc18-1 is replaced by a mutated form of Munc18-1 that cannot be phosphorylated. The main finding is that most PTP at hippocampal CA3 to CA1 synapses, or at cerebellar granule cell to Purkinje cell synapses does not rely on PKC phosphorylation of Munc18-1. Thus, mechanisms independent of PKC phosphorylation of Munc18-1 are important mediators of PTP.

Two coordination polymers (CPs), with chemical formulas {[Ni2(bpp)2(BT)(H2O)6] 1.5(EtOH) 1.5H2O}n (1) and [Zn(bpp)(BT)0.5]·5H2O (2) (bpp = 1,3-bis(4-pyridyl)propane, and BT4− = tetraanion of 1,2,4,5-Benzenetetracarboxylic acid), have been synthesized and structurally characterized by single-crystal X-ray diffraction methods. In compound 1, the coordination environments of two crystallographically independent Ni(II) ions are both distorted octahedral bonded to two nitrogen donors from two bpp ligands and four oxygen donors from one BT4- ligand and three water molecules. Both bpp and BT4− act as bridging ligands with bis-monodentate and 1,4-bis-monodentate coordination modes, respectively, connecting the Ni(II) ions to form a 2D layered metal-organic framework (MOF). Adjacent 2D layers are then arranged orderly in an ABAB manner to complete their 3D supramolecular architecture. In 2, the coordination environment of Zn(II) ion is distorted tetrahedral bonded to two nitrogen donors from two bpp ligands and two oxygen donors from two BT4− ligands. Both bpp and BT4- act as bridging ligands with bis-monodentate and 1,2,4,5-tetrakis-monodentate coordination modes, respectively, connecting the Zn(II) ions to form a 3D MOF. The reversible water de-/adsorption behavior of 1 between dehydrated and rehydrated forms has been verified by cyclic Thermogravimetric (TG) analyses through de-/rehydration processes. Compound 1 also exhibits significant water vapor hysteresis isotherms.

A two-dimensional (2D) coordination polymer, [Co(4-dpds)(bdc)(H2O)2]&middot, 4-dpds (1) (4-dpds = 4,4&prime, dipyridyldusulfide and bdc2&minus, = dianion of benzenedicarboxylic acid), has been synthesized and structurally determined by single-crystal X-ray diffractometer. In 1, the bdc2&minus, and 4-dpds both act as bridging ligands connecting the Co(II) ions to form a 2D wrinkled-like layered coordination polymer. Two wrinkled-like layered coordination polymers are mutually penetrated to generate a doubly interpenetrated framework, and then extended to its 3D architecture via the supramolecular forces between doubly interpenetrated 2D frameworks and free 4-dpds ligands by intermolecular O&ndash, H&sdot, &sdot, N hydrogen bonding interaction. Crystal packing arrangements were characterized by fingerprint plots, which were derived from the Hirshfeld Surfaces analysis, and showed that intermolecular hydrogen bonding interactions are the most important interactions on the construction of the crystal 1.

Tumor denervation limits cancer growth, but the mechanisms behind this are unknown. We find that malignant melanoma cells interact with pain-initiating nociceptor neurons by increasing neurite outgrowth, responsiveness to noxious ligands and neuropeptide release. In turn, nociceptor-produced neuropeptides increase exhaustion of cytotoxic T cells (PD1+Lag3+Tim3+INFγ-), limiting their capacity to eliminate melanoma cells. Genetic TRPV1 or NaV1.8 lineage ablation, local pharmacological silencing as well as blockade of vesicle release from tumor-innervating nociceptors enhance tumor-infiltrating leukocyte (TIL) numbers and increase survival of mice subject to orthotropic melanoma inoculation, blunting tumor growth and TIL exhaustion. We conclude that reducing neuropeptide release from tumor-innervating nociceptors, by eliminating their immunomodulatory action on cytotoxic CD8 T cell, may be a useful therapeutic intervention to boost immune surveillance.

Ultrathin coatings (1.5 ± 0.3 nm) of titanium dioxide and zinc oxide were deposited on lithium-rich layered oxide cathodes (Li1.2Mn0.6Ni0.2O2, LLO) by atomic layer deposition (ALD). The structures, electrochemical performances, and thermal stabilities of these coatings were investigated. An ultrathin uniform coating was obtained for TiO2 but not for ZnO because of differences in the layer growth mechanism. Regarding the initial charge–discharge curves under a current density of 0.04 C rate, the TiO2 coated samples exhibited a higher discharge capacity, 242 mAhg–1, compared with the ZnO coated samples, 220 mAhg–1, or the pristine samples, 228 mAhg–1. Both coated samples exhibited more stable cycling performance and thermal stability than the pristine samples. After 80 cycles under 0.5 C rate, the TiO2 and ZnO coated samples were found to have higher capacity retention (∼94% and 78%, respectively) than the pristine samples (68%). The reaction temperature of the exothermic peak of the TiO2 and ZnO coated sam...

Highly homogeneous Al- and Zn-doped TiO2 nanotubes were fabricated by atomic layer deposition (ALD) via nanolaminated stacks of binary layers of TiO2/Al2O3 and TiO2/ZnO, respectively. The bilayers were alternately deposited on the polycarbonate (PC) membrane template by ALD with various cyclic sequences. The nanotubes in a length of 20 μm and a diameter of 220 nm were obtained after removal of the PC membrane by annealing at 450 °C. The effects of doping composition on the photocatalytic and photoelectrochemical (PEC) activities were investigated. Increasing the Al doping reduced the photocatalytic activity of TiO2 due to formation of charge recombination sites and reduction of hydroxide radicals. In contrast, there was an optimal range of Zn doping to get enhanced photocatalytic activity and higher PEC efficiency. With a doping ratio of 0.01, the hydrogen production rate from water splitting was 6 times higher than that of commercial P25 TiO2. The energy-band diagram of Zn-doped TiO2 determined by ultraviolet photoelectron spectroscopy revealed shift up of the Fermi level to provide more electrons to the conduction band. The photoinduced trapped electrons and holes were detected in Zn-doped TiO2 by in situ electron paramagnetic resonance spectroscopy, which revealed that Ti3+ sites on the surface and surface oxygen vacancies played a key role in promoting the photocatalytic process.