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Metal–support interfacial interactions can enrich the electron density of Bi2O3 effectively facilitating *COO intermediate generation and boosting catalytic activity.

Theories of prediction-for-perception propose that the brain predicts the information contents of upcoming stimuli to facilitate their perceptual categorization. A mechanistic understanding should therefore address where, when, and how the brain predicts the stimulus features that change behavior. However, typical approaches do not address these predicted stimulus features. Instead, multivariate classifiers are trained to contrast the bottom-up patterns of neural activity between two stimulus categories. These classifiers then quantify top-down predictions as reactivations of the category contrast. However, a category-contrast cannot quantify the features reactivated for each category–which might be from either category, or both. To study the predicted category-features, we randomly sampled features of stimuli that afford two categorical perceptions and trained multivariate classifiers to discriminate the features specific to each. In a cueing design, we show where, when and how trial-by-trial category-feature reactivation strength directly biases decision behavior, transforming our conceptual and mechanistic understanding of prediction-for-perception.

Herein, we report a facile strategy for constructing the hybrid coordination configurations by combination of the functional graphene quantum dots with CoPc (CoPc/R-GQD, with R being -NH2 or -OH) for...

Excessive mechanical stress is closely associated with progression of osteoarthritis (OA). Pathological mechanical stress can lead to chondrocyte apoptosis and subsequent cartilage degeneration. Piezo1 is a recently identified mechanosensitive ion channel that mediates chondrocyte response to mechanical stress. Here, we investigated the potential role of Piezo1 in chondrocyte apoptosis and cartilage degeneration induced by excessive mechanical stress. The primary mouse chondrocytes were subjected to mechanical stretch stress for 0, 6, 12 and 24 h, respectively. Western blot, quantitative real-time polymerase chain reaction, immunofluorescence, lysosomes and acridine orange staining were applied to examine levels of Piezo1, lysosomal function, chondrocyte apoptosis and cartilage degeneration. In vivo studies, DMM mouse model was performed to explore the protective effects and underlying mechanisms of Piezo1 inhibition on chondrocyte apoptosis and articular cartilage degradation. Exposure of chondrocytes to excessive mechanical loading caused lysosomal membrane permeabilization (LMP), which increased chondrocyte apoptosis and cartilage degeneration. Moreover, Piezo1 was upregulated in mechanical stress treated chondrocytes, and Piezo1 inhibition by siRNA or pharmacological inhibitor attenuated LMP, chondrocyte apoptosis and cartilage degeneration. We also found that Piezo1 activated cPLA2 through the calcium signaling, and cPLA2 subsequently caused the occurrence of LMP. Finally, the DMM mouse model revealed that Piezo1 inhibition reduced cPLA2 induced LMP, thereby ameliorated the surgery induced chondrocyte apoptosis and cartilage degradation, and attenuated OA pathological process. In summary, our study indicates that activity of Piezo1 was the culprit in the excessive mechanical stress-induced LMP and cartilage degradation, and Piezo1 inhibition may be a promising strategy for OA treatment.

We developed a tandem electrocatalyst for CO2 -to-CO conversion comprising the single Cu site co-coordinated with N and S anchored carbon matrix (Cu-S1 N3 ) and atomically dispersed Cu clusters (Cux ), denoted as Cu-S1 N3 /Cux . The as-prepared Cu-S1 N3 /Cux composite presents a 100 % Faradaic efficiency towards CO generation (FECO ) at -0.65 V vs. RHE and high FECO over 90 % from -0.55 to -0.75 V, outperforming the analogues with Cu-N4 (FECO only 54 % at -0.7 V) and Cu-S1 N3 (FECO 70 % at -0.7 V) configurations. The unsymmetrical Cu-S1 N3 atomic interface in the carbon basal plane possesses an optimized binding energy for the key intermediate *COOH compared with Cu-N4 site. At the same time, the adjacent Cux effectively promotes the protonation of *CO2 - by accelerating water dissociation and offering *H to the Cu-S1 N3 active sites. This work provides a tandem strategy for facilitating proton-coupled electron transfer over the atomic-level catalytic sites.

Electrochemical conversion of NO3- to NH3 production is of great environmental significance for water pollution treatment and can artificially close the nitrogen cycle. However, direct nine proton and eight electron transfer leads to low Faraday efficiency (FE) and yield. Herein, the single copper site immobilized on N, P co-doped carbon substrates (Cu-N4/P) was prepared for efficient NO3–to-NH3 conversion. Benefiting from electronic redistribution of Cu site induced by the introduction of the less electronegative element P, Cu-N4/P catalyst has superior catalytic properties to the comparison sample, including 100% NO3- conversion, high FE (96.12%) and NH3 yield (124.22 mmol/(h·gcat)). Density functional theory (DFT) explains the effective operation mechanism that P doping can promote the spontaneous hydrogenation of *NO to form *NOH, thus promoting the formation of NH3 from NO3- reduction reaction. The heteroatom doping strategy mentioned proposes a new approach for promoting NO3–to-NH3 conversion at atomic level catalytic sites.

Models of visual cognition assume that brain networks predict the contents of a stimulus to facilitate its subsequent categorization. However, the specific network mechanisms of this facilitation remain unclear. Here, we studied them in 11 individual participants cued to the spatial location (left vs. right) and contents (Low vs. High Spatial Frequency, LSF vs. HSF) of an upcoming Gabor stimulus that they categorized. Using concurrent MEG recordings, we reconstructed in each participant the network that communicates the predicted contents and the network that represents these contents from the stimulus for categorization. We show that predictions of LSF vs. HSF propagate top-down from temporal to contra-lateral occipital cortex, with modulatory supervision from frontal cortex. In occipital cortex, predictions sharpen bottom-up stimulus LSF vs. HSF representations, leading to faster categorizations. Our results therefore reveal functional networks that predict visual contents to sharpen their representations from the stimulus to facilitate categorization behavior.

The prevalent conception of vision-for-categorization suggests an interplay of two dynamic flows of information within the occipito-ventral pathway. The bottom-up flow progressively reduces the high-dimensional input into a lower-dimensional representation that is compared with memory to produce categorization behavior. The top-down flow predicts category information (i.e. features) from memory that propagates down the same hierarchy to facilitate input processing and behavior. However, the neural mechanisms that support such dynamic feature propagation up and down the visual hierarchy and how they facilitate behavior remain unclear. Here, we studied them using a prediction experiment that cued participants (N = 11) to the spatial location (left vs. right) and spatial frequency (SF, Low, LSF, vs. High, HSF) contents of an upcoming Gabor patch. Using concurrent MEG recordings of each participant’s neural activity, we compared the top-down flow of representation of the predicted Gabor contents (i.e. left vs. right; LSF vs. HSF) to their bottom-up flow. We show (1) that top-down prediction improves speed of categorization in all participants, (2) the top-down flow of prediction reverses the bottom-up representation of the Gabor stimuli, going from deep right fusiform gyrus sources down to occipital cortex sources contra-lateral to the expected Gabor location and (3) that predicted Gabors are better represented when the stimulus is eventually shown, leading to faster categorizations. Our results therefore trace the dynamic top-down flow of a predicted visual content that chronologically and hierarchically reversed bottom-up processing, further facilitates visual representations in early visual cortex and subsequent categorization behavior.

We developed a tandem electrocatalyst for CO

Current cognitive theories are cast in terms of information-processing mechanisms that use mental representations1–4. For example, people use their mental representations to identify familiar faces under various conditions of pose, illumination and ageing, or to draw resemblance between family members. Yet, the actual information contents of these representations are rarely characterized, which hinders knowledge of the mechanisms that use them. Here, we modelled the three-dimensional representational contents of 4 faces that were familiar to 14 participants as work colleagues. The representational contents were created by reverse-correlating identity information generated on each trial with judgements of the face’s similarity to the individual participant’s memory of this face. In a second study, testing new participants, we demonstrated the validity of the modelled contents using everyday face tasks that generalize identity judgements to new viewpoints, age and sex. Our work highlights that such models of mental representations are critical to understanding generalization behaviour and its underlying information-processing mechanisms. What aspect of faces do we use to recognize familiar people? Zhan et al. model the three-dimensional information contents that represent faces in the memory of their colleagues. This information is relevant for recognition across viewpoints, age and sex.

Is face beauty universally perceived from a common basis of objectively definable face features, or is it irreducibly subjective and in the idiosyncratic eye of the cultural, or even individual beholder? We addressed this longstanding debate by objectively modelling the face beauty preferences of 80 individual male participants across Western European (WE) and East Asian (EA) cultures. With state-of-the-art 3D face capture technology, we derived a generative model that synthesized on each trial a random WE or EA female face whose shape and complexion is constrained by natural face variations. Each participant rated the attractiveness of the face on a Likert scale. We then reverse correlated these subjective ratings with the synthesized shape and complexion face parameters to reconstruct individual face models of attractiveness for same and other ethnicity faces. By analyzing the resulting 80 individual models and reconstructing the representation space of face beauty, we addressed several key questions. Against popular belief, we show that the most attractive faces are not average face. Instead, attractive features are at the outskirts of the natural distribution of face variations, suggesting a selection pressure away from the average. Such features also form their own subspace that is separate from cues of sexual dimorphism (i.e. masculine vs. feminine). Finally, we reveal the global preferences of face features across cultures, and specific cultural and individual participant idiosyncrasies. Our results therefore represent face attractiveness in its diversity to inform and impact fundamental theories of human social perception and signalling and the design of globalized digital avatars.

The information contents of memory are the cornerstone of the most influential models in cognition. To illustrate, consider that in predictive coding, a prediction implies that specific information is propagated down from memory through the visual hierarchy. Likewise, recognizing the input implies that sequentially accrued sensory evidence is successfully matched with memorized information (categorical knowledge). Although the existing models of prediction, memory, sensory representation and categorical decision are all implicitly cast within an information processing framework, it remains a challenge to precisely specify what this information is, and therefore where , when and how the architecture of the brain dynamically processes it to produce behaviour. Here, we review a framework that addresses these challenges for the studies of perception and categorization–stimulus information representation (SIR). We illustrate how SIR can reverse engineer the information contents of memory from behavioural and brain measures in the context of specific cognitive tasks that involve memory. We discuss two specific lessons from this approach that generally apply to memory studies: the importance of task, to constrain what the brain does, and of stimulus variations, to identify the specific information contents that are memorized, predicted, recalled and replayed. This article is part of the Theo Murphy meeting issue ‘Memory reactivation: replaying events past, present and future’.

It is always a challenge to prepare multifunctional epoxy resins (EP) composites with excellent flame retardance, mechanical property and high transparency. In this work, a reactive flame-retardant (BDO) was synthesized from DOPO, 3,5-diamino-triazolz and thiophene-2-formaldehyde, and taken to prepare EP/BDO composites. Surprisingly, benefitting from the synergy of efficient flame retardant unit (DOPO structure), catalytic curing unit (triazole structure) and optical functional structure (thiophene-2-formaldehyde), the EP composites with excellent comprehensive performance was obtained. In detailed, after adding only 5 wt% BDO, the EP composites passed the UL-94 V-0 level, and the limiting oxygen index was increased to 33% from 22.5% of neat EP. At the same time, EP/BDO-5 showed obvious heat suppression and smoke suppression effects. Besides, EP/BDO-5 presented excellent mechanical strength, that the tensile strength and bending strength were increased by 25% and 30% compared with neat EP. Moreover, EP/BDO composites maintained the same good light transmittance as neat EP, and also presented enhanced Tg and dielectric property. In addition, the dual phase flame-retardant mechanism was revealed through systematically analyzing residues after combustion and the gaseous phase products of flame retardant. The above results indicated EP/BDO composites with excellent comprehensive performance possessed a great potential application in high-performance composites fields.

In this paper, the waste polyphenylene sulfide (PPS) filter bag was converted to waste PPS powder through thermal aging, ball milling and screening, and firstly used as flame retardant to improve the flame retardance of epoxy resin (EP). TG results presented that, it started to decompose at 510.6 °C with 62.08% of residue mass at 800 °C, which showed good charring ability. The UL-94 and cone calorimeter tests showed that waste PPS not only improved the flame retardance of EP but also largely decreased heat and smoke/toxic gases release. Adding 15 wt% waste PPS made EP composites acquire a UL-94 V-1 rating and resulted in a 42.24% reduction in the peak of heat release rate (PHRR). What’ more, the peak of smoke production rate (PSPR) and peak of CO production (PCOP) declined by 27.27% and 45.16%. The morphology of char residue was also observed by scanning electron microscope (SEM), and it was concluded that, introduction of waste PPS indeed improved the compact of char layer, which was be responsible for enhancement in flame retardance. This work provided a new way and theoretical basis for realizing high value recycling of PPS solid waste.

Communication involves successfully deriving a speaker's meaning beyond the literal expression. Using fMRI, it was investigated how the listener's brain realizes distinctions between enrichment-based meanings and literal semantic meanings. The neural patterns of the Mandarin scalar quantifier you-de (similar to some in English) which implies the meanings not all and not most via scalar enrichment, with the specific quantifier shao-shu-de (similar to less than half in English) which lexico-semantically encodes the meanings not all and not most, were compared. Listeners heard sentences using either quantifier, paired with pictures in which either less than half, more than half, or all of the people depicted in the picture were doing the described activity; thus, the conditions included both implicature-based and semantics-based picture-sentence mismatches. Imaging results showed bilateral ventral IFG was activated for both kinds of mismatch, whereas basal ganglia and left dorsal IFG were activated uniquely for implicature-based mismatch. These findings suggest that resolving conflicts involving inferential aspects of meaning employs different neural mechanisms than the processing based on literal semantic meaning, and that the dorsal prefrontal/basal ganglia pathway makes a contribution to implicature-based interpretation. Furthermore, within the implicature-based conditions, different neural generators were implicated in the processing of strong implicature mismatch (you-de in the context of a picture in which "all" would have been true) and weak implicature mismatch (you-de in the context of a picture in which "most" would have been true), which may have important implications for theories of pragmatic comprehension. Hum Brain Mapp 38:3848-3864, 2017. © 2017 Wiley Periodicals, Inc.

Carbide slag produced from chlor-alkali industry contains high amounts of calcium compounds and can potentially be used as raw material for cement production; however, it contains large amounts of chlorine so it is essential to evaluate the emissions of chlorinated organic pollutants, including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polychlorinated naphthalenes (PCNs). A field study of the emission profiles of these pollutants in a cement plant using such slag was performed. The average concentrations of PCDD/Fs, PCBs, and PCNs in stack gases collected at the kiln back end were 6.31, 1.07, and 31.89 pg TEQ m−3, respectively. PCDFs dominated over PCDDs in particulate samples. Di- to pentachlorinated biphenyls were dominant homologs in the particulate samples. MonoCBs were the dominant homolog in stack gases from the kiln back end, and homolog concentrations decreased with increasing chlorine numbers. Mono- and diCNs accounted for 48–98% of PCNs. The estimated toxic equivalents of stack gas emissions of PCNs, classified as new persistent organic pollutants under Stockholm Convention, were unexpectedly higher than those of PCDD/Fs and PCBs. A mass balance indicated that all of the toxic equivalents were reduced by this cement kiln system. The highest 2,3,7,8-PCDD/F output is with clinker.

A field study and theoretical calculations on the profile and formation mechanism of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from two cement kilns co-incinerating municipal solid waste and sewage sludge were performed, and the PCDFs were mainly focused. The back-end areas of the cement kilns were identified to be the major sites of PCDD/F formation according to their distributions in particulate samples from different process stages. The proportions of tetra- to hexa-chlorinated dibenzofurans (∑Cl4–6CDFs) at the kiln back-end areas were in the range of 50–80% of the total PCDD/Fs in mass concentrations and 62–87% in toxic equivalent concentrations. These results indicated that ∑Cl4–6CDFs are the dominant homologs that should be the focus for reducing PCDD/F emissions in cement kilns that co-incinerate municipal solid waste and sewage sludge. It is speculated that the low contents of oxygen and copper compounds, as well as the alkaline conditions, may contribute to the dominance of ∑Cl4–6CDFs in the PCDD/Fs formed. Chlorination was assumed to be the mechanism of formation of PCDFs. The results from model predictions and thermodynamic calculations used to test this assumption were consistent with the PCDF profiles observed from the field study.

Cement kilns can be used to co-process fly ash from municipal solid waste incinerators. However, this might increase emission of organic pollutants like polychlorinated biphenyls (PCBs). Knowledge of PCB concentrations and homolog and congener patterns at different stages in this process could be used to assess the possibility of simultaneously controlling emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and “dioxin-like” compounds. To date, emissions from cement kilns co-processing fly ash from municipal solid waste incinerators have not been analyzed for PCBs. In this study, stack gas and particulate samples from two cement kilns co-processing waste incinerator fly ash were analyzed for PCBs. The average total tri- to deca-chlorinated biphenyl (∑3–10PCB) concentration in the stack gas samples was 10.15 ng m−3. The ∑3–10PCB concentration ranges in particulate samples from different stages were 0.83–41.79 ng g−1 for cement kiln 1 and 0.13–1.69 ng g−1 for cement kiln 2. The ∑3–10PCB concentrations were much higher in particulate samples from the suspension pre-heater boiler, humidifier tower, and kiln back-end bag filters than in particulate samples from other stages. For these three stages, PCBs contributed to 15–18% of the total PCB, PCDD/F, and polychlorinated naphthalene toxic equivalents in stack gases and particulate matter. The PCB distributions were similar to those found in other studies for PCDD/Fs and polychlorinated naphthalenes, which suggest that it may be possible to simultaneously control emissions of multiple organic pollutants from cement kilns. Homolog patterns in the particulate samples were dominated by the pentachlorobiphenyls. CB-105, CB-118, and CB-123 were the dominant dioxin-like PCB congeners that formed at the back-end of the cement kiln. A mass balance of PCBs in the cement kilns indicated that the total mass of PCBs in the stack gases and clinker was about half the mass of PCBs in the raw materials.

A novel polycarboxylate superplasticizer (PCE) was synthesized by graft copolymerization between acrylic acid (AA) and end-functionalized poly (allyl sulfonate) (PALS) to produce comb polymer, i.e. PAA-g-PALS. The molecular structure was confirmed by Infrared Spectroscopy (IR) and 1H Nuclear Magnetic Resonance (1H NMR), and the molecular properties were characterized by Gel Permeation Chromatography (GPC). The conventional PCE with comb structure using isobutenyl polyethylene glycol (IPEG) as side chains (i.e. PAA-g-IPEG) was also synthesized to explore the effect of the side chain on the PCE performances. The fluidity and its retention, rheological properties, hydrodynamic radii (Rh), adsorption behavior and zeta potential of the cement pastes containing PAA-g-PALS or PAA-g-IPEG were comparatively tested. It was found that this designed “sulfonate modified PCE” exhibited stronger dispersing stability and sulfate tolerance to cement paste and less sensitive to the sulfate competitive adsorption and the increase in ionic strength. Based on the above results, the evaluation method (the sulfate resistance index of PAA-g-PALS was increased by 24% as compared to that of PAA-g-IPEG) was innovatively established and the mechanism of sulfate resistance was clarified in detail. The purpose of this research is to offer an avenue with great potentials to synthesize a novel PCE with excellent workability retention and sulfate tolerance in fresh cement pastes. This sulfonate-modified polycarboxylate superplasticizer has great potentials as a viable alternative to conventional PCE, especially in some harsh cement systems.

In this work, a fully biodegradable poly(butylene succinate) (PBS) biocomposite was fabricated from ultrafine PBS fiber and waste paper (WP) using a paper-manufacturing and compression molding method. A PBS biocomposite containing 60 wt% WP showed a tensile strength, elongation at break, flexural strength, flexural modulus, interlaminar shear strength (ILSS), and impact strength of 78.1 MPa, 11.1%, 92.0 MPa, 7.5 GPa, 2.9 MPa, and 36.9 kJ/m2, respectively, which were superior to those of previously-reported PBS biocomposites. The damage mechanics reveals that tremendous deformation of plant fibers (PF) from WP and their riveting improved the mechanical properties of WP/PBS biocomposites. The weight loss ratio of WP/PBS-60 wt% biocomposite during biodegradation reached 95.1 wt% after immersion in an enzyme solution for 35 d. This fabrication approach provides a novel and facile strategy to develop high-performance, low-cost, and fully biodegradable PBS biocomposites.

Co-processing municipal solid waste incinerator (MSWI) fly ash in cement kilns is challenging because the unintentional production of persistent organic pollutants (POPs) during the process is not well understood. The distributions, profiles and formation mechanisms of polychlorinated naphthalenes (PCNs) as new POPs covered under Stockholm Convention in two cement kilns co-processing MSWI fly ash were studied. The average concentrations of PCNs in stack gas samples were 710 ng m−3. The PCN concentration in particle samples collected from different process stages in the cement kilns ranged from 1.1 to 84.7 ng g−1. Three process sites including suspension pre-heater boiler, humidifier tower, and the kiln back-end bag filter were identified to be the major formation sites of PCNs in cement kilns co-processing MSWI fly ash. The PCN distribution patterns were similar to that of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/Fs), which indicates the possibility for simultaneous control of PCNs and PCDD/Fs in cement kilns co-processing fly ash. Chlorination was suggested to be an important formation mechanism of PCNs, and chlorination pathways of PCN congeners are proposed based on the congener profiles. Thermodynamic calculations, including relative thermal energies (ΔE) and standard free energy of formation (ΔG), and the charge densities of the carbon atoms in PCN supported the proposed chlorination mechanisms for PCN formation. The results presented in this study might provide helpful information for developing techniques and strategies to control PCN emissions during cement kilns co-processing MSWI fly ash.

Industrial activities result in unintentional production of multiple types of persistent organic pollutants (POPs) at various concentrations. Because of the potential adverse effect of these POPs on the environment, biota and human health, methods for controlling emission of POPs are required. Development and application of techniques for controlling emissions of POPs can be a technical and economic burden for the industry involved. Therefore, from the point of view of cost-benefit analysis, reducing emissions of multiple pollutants at the same time is optimal for sustainable industrial development. Although techniques have been developed for reducing the emissions of individual POPs, such as dioxins, further work is required on multi-POP control emissions from industrial activities. This paper discusses three important aspects that need to be taken to achieve multi-POP control. These aspects include the establishment of a comprehensive system for evaluating the risk from emissions of multiple POPs, determination of indicators for total emissions of multiple POPs, and the preparation and application of functional materials to inhibit formation of multiple POPs. These discussion might be helpful for the future research on the multi-POP control in industry.

A pilot study was performed to evaluate formation, distribution and emission of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from cement kilns that co-process fly ash from municipal solid waste incineration (MSWI). Stack gas and particulate samples from multiple stages in the process were collected and analyzed for PCDD/Fs. Stack emissions of PCDD/Fs were below the European Union limit for cement kilns (0.1 ng TEQ m(-3)). PCDD/F concentrations in particulates from the cyclone preheater outlet, suspension preheater boiler, humidifier tower, and back-end bag filter were much higher than in other samples, which suggests that these areas are the major sites of PCDD/F formation. Comparison of PCDD/F homolog and congener profiles from different stages suggested that tetra- and penta-chlorinated furans were mainly formed during cement kiln co-processing of MSWI fly ash. Three lower chlorinated furan congeners, including 2,3,7,8-tetrachlorodibenzofuran, 1,2,3,7,8-pentachlorodibenzo-p-dioxin and 2,3,4,7,8-pentachlorodibenzofuran, were identified as dominant contributors to the toxic equivalents (TEQ) of the PCDD/Fs. The concentration of PCDD/Fs in particulates was correlated with chloride content, which is consistent with its positive effect on PCDD/F formation. This could be mitigated by pretreating the feedstock to remove chloride and metals. Mass balance indicated that cement kilns eliminated about 94% of the PCDD/F TEQ input from the feedstock.

Herein, we used intense shear to construct caterpillar-like continuous hierarchical fibers (CLCHF). This architecture was then modified with mussel inspired poly(dopamine) (PDA) and γ-methacryloxypropyl trimethoxy silane (KH570) in a one-step method. Finally, employing (PDA + KH570)@CLCHF and compounded with poly(butylene succinate) (PBS) ultrafine fiber, (PDA + KH570)@CLCHF/PBS biocomposite was manufactured by combining intense shear and thermal-compression method. In virtue of intense shear, CLCHF can be effectively produced with nanoscale fibrils from 2 nm to 28 nm and (PDA + KH570)@CLCHF and PBS ultrafine fibers displayed favorable homogenization in aqueous solution. More importantly, the interspace between (PDA + KH570)@CLCHF and PBS ultrafine fibers could be optimized to facilitate infiltration at high filler content in polymers. The results also showed that the PBS biocomposite with 30 wt% (PDA + KH570)@CLCHF displayed optimal mechanical performance. Its tensile strength, elastic modulus, flexural strength, flexural modulus and impact strength reached to 120.2 MPa, 6.4 GPa, 110.1 MPa, 4.0 GPa and 23.5 kJ/m2, respectively. It is noticeble that the tensile properties were superior to some previously reported PBS biocompoistes due to the ability of CLCHF to effectively hinder the aggregation of numerous microcracks and slow crack tip propagation. The (PDA + KH570)@CLCHF/PBS biocomposites reported here can be used as desirable substitutes for nondegradable composites due to its high value added and favorable mechanical performance, and may broaden the application prospect of PBS biocomposite.

Subsequent to the sharp surge in quantity of municipal solid waste (MSW) generation, the pace at which waste treatment facilities are being constructed in some cities cannot meet the increasing demand for MSW treatment capacity. As a remedy to this, the co-processing of MSW in high-temperature cement kilns has become a potential MSW treatment option in emerging countries, and has been widely implemented in developed countries such as Netherlands and Germany. However, the environmental impacts of MSW co-processing in cement kilns differ from those of traditional treatment technologies. Besides, it is necessary to determine whether MSW co-processing in cement kilns could reduce the overall environmental impacts of MSW treatment and disposal as a whole, which is a key step in analyzing the feasibility of the treatment technology. Hence, this study used the life cycle assessment (LCA) method to quantitatively analyze the environmental impacts of MSW co-processing in cement kilns and the results further compared with other MSW treatment technologies. The functional unit was one ton of raw MSW, and real operational data from the cement industry and MSW treatment project in China was used for case studies. The results revealed that when compared to incineration and mechanical biological treatment (MBT), the environmental impact mitigation of energy recovery during MSW co-processing in cement kilns is not that significant. However, since there is no required additional treatment of residual waste and wastewater, the environmental impact caused by MSW co-processing in cement kiln appeared to be much lower from a life cycle perspective. Therefore, under conditions of insufficient MSW treatment capacity, co-processing in cement kiln could be an effective complementary approach to MSW management in China and other emerging countries which have many new dry cement kilns suitable for this alternative complementary technique of MSW treatment and disposal.

Social robots are now part of human society, destined for schools, hospitals, and homes to perform a variety of tasks. To engage their human users, social robots must be equipped with the essential social skill of facial expression communication. Yet, even state-of-the-art social robots are limited in this ability because they often rely on a restricted set of facial expressions derived from theory with well-known limitations such as lacking naturalistic dynamics. With no agreed methodology to objectively engineer a broader variance of more psychologically impactful facial expressions into the social robots' repertoire, human-robot interactions remain restricted. Here, we address this generic challenge with new methodologies that can reverse-engineer dynamic facial expressions into a social robot head. Our data-driven, user-centered approach, which combines human perception with psychophysical methods, produced highly recognizable and human-like dynamic facial expressions of the six classic emotions that generally outperformed state-of-art social robot facial expressions. Our data demonstrates the feasibility of our method applied to social robotics and highlights the benefits of using a data-driven approach that puts human users as central to deriving facial expressions for social robots. We also discuss future work to reverse-engineer a wider range of socially relevant facial expressions including conversational messages (e.g., interest, confusion) and personality traits (e.g., trustworthiness, attractiveness). Together, our results highlight the key role that psychology must continue to play in the design of social robots.

In the sciences of cognition, an influential idea is that the brain makes predictions about incoming sensory information to reduce inherent ambiguity. In the visual hierarchy, this implies that information content originating in memory–the identity of a face–propagates down to disambiguate incoming stimulus information. However, understanding this powerful prediction-for-recognition mechanism will remain elusive until we uncover the content of the information propagating down from memory. Here, we address this foundational limitation with a task ubiquitous to humans–familiar face identification. We developed a unique computer graphics platform that combines a generative model of random face identity information with the subjectivity of perception. In 14 individual participants, we reverse engineered the predicted information contents propagating down from memory to identify 4 familiar faces. In a follow-up validation, we used the predicted face information to synthesize the identity of new faces and confirmed the causal role of the predictions in face identification. We show these predictions comprise both local 3D surface patches, such as a particularly thin and pointy nose combined with a square chin and a prominent brow, or more global surface characteristics, such as a longer or broader face. Further analyses reveal that the predicted contents are efficient because they represent objective features that maximally distinguish each identity from a model norm. Our results reveal the contents that propagate down the visual hierarchy from memory, showing this coding scheme is efficient and compatible with norm-based coding, with implications for mechanistic accounts of brain and machine intelligence.

Triphase polyimide nanocomposite films were fabricated using barium titanate (BaTiO3) with high dielectric constant and silver (Ag) with high conductivity as fillers. In situ method was utilized to obtain the homogeneous dispersion of nanoparticles. The in situ polymerization of polyimide precursor-poly(amic acid) was performed in the presence of BaTiO3 particles. Silver compound 1,1,1-trifluoro-2,4-pentadionato silver(I) was added into the BaTiO3 containing poly(amic acid) solution to achieve silver nanoparticles via in situ self metallization technique. The thermally induced reduction converted silver (I) to metallic silver with concomitant imidization of poly(amic acid) to polyimide. Both BaTiO3 and silver nanoparticles were uniformly dispersed in the polyimide substrate. The dependence of dielectric behavior on the BaTiO3 and Ag contents was studied. The incorporation of small amount of silver nanoparticles greatly increased dielectric constant of composite films.

Co-incineration of sewage sludge in cement kilns can be used for its disposal. In the present study, samples were collected from three cement production runs where sewage sludge and other wastes (e.g. municipal solid waste, waste acid and wet sewage sludge) were co-processed. The samples were analyzed for polychlorinated biphenyls (PCBs). The dioxin-like (dl)-PCB concentrations in the stack gases from run 1, 2, and 3 were 344.6, 548.7, and 104.3 pg m −3 , respectively. The toxic equivalency (TEQs) values for runs 1, 2, and 3 were 5.6, 8.9, and 0.7 pg TEQ Nm −3 , respectively. Calculation of net emissions for the three runs indicated that the co-incineration of other waste in addition to sewage sludge in cement kilns would not increase emission of the dl-PCBs. PCB concentrations in samples from the suspension boiler and humidifier tower, kiln-end bag filter, and cyclone preheater were much higher than those in samples from the kiln head area, indicating that these stages will be important for controlling PCB formation. Chlorinated biphenyl (CB)-77, CB-105 and CB-118 were the major dl-PCB congeners, CB-52, CB-101 were the major indicator PCB congeners, and tetra-CB to hexa-CB were the major homologues for the total input or output materials.

Pilot studies of unintentionally produced pollutants should be performed before waste being co-processed in cement kilns. Polychlorinated naphthalene (PCN) formation and emission from cement kilns co-processing sorted municipal solid waste, sewage sludge, and waste acid, however, have not previously been studied. Here, PCNs were analyzed in stack gas samples and solid samples from different stages of three cement production runs. PCN destruction efficiencies were higher when waste was co-processed (93.1% and 88.7% in two tests) than when waste was not co-processed (39.1%), so co-processing waste would not increase PCN outputs. The PCN concentrations were higher in particle samples from the C1 preheater and stages at back end of kiln than in particle samples from other stages, suggesting that cyclone preheater and back end of kiln should be focused for controlling PCN emissions. Besides that, based on the variation of PCN concentrations and corresponding operating conditions in different stages, the temperature, feeding materials, and chlorine content were suggested as the main factors influencing PCN formation. The PCN homologue and congener profiles suggested chlorination and dechlorination were the main PCN formation and decomposition pathways, and congeners CN-23, CN-46, and CN-59 appear to be appropriate indicators of PCNs emitted from coal-burning sources.

Formation process and mechanism of continuous CuO layers on double surfaces of polyimide films were studied. The composite films were prepared using the facile surface modification and ion exchange technique. By alkaline-induced chemical modification and ion-exchange reaction, Cu 2+ ions were incorporated into the surface of polyimide substrate. Thermal treatment in ambient atmosphere resulted in the formation of CuO particles that further agglomerated on the film surface and produced well-defined CuO thin layers on the double surfaces of polyimide films. The changes in the chemical structure, surface morphology, crystalline state and the surface roughness with the increase of ambient temperature were investigated. It was interesting to find that the conversion of metallic copper and low valence sub-oxide Cu 2 O to high valence oxide CuO was observed in the thermal treatment process. The agglomeration mechanism for the CuO particles was proposed and proved by three steps, which illustrated that copper-catalyzed and oxygen-assisted decomposition of the polyimide overlayer resulted in the agglomeration of CuO particles. The final composite films retained the thermal stability of the pure polyimide.

Polyimide/sepiolite nanocomposite films have been prepared via an in situ polymerization method. The process involves the dispersion of sepioite in N,N-dimethylacetamide, polycondensation of 2,2′-bis [4-(3,4-dicarboxyphenoxy) phenyl] propane dianhydride and 4,4′-oxydianiline in the presence of sepiolite suspension to form poly(amic acid), and the thermal imidization of poly(amic acid)/sepiolite nanocomposite. The morphology, thermal and mechanical performance, and water absorption of nanocomposite films were systematically studied with various sepiolite contents. The results indicated that sepiolite was dispersed homogeneously at a nanometer scale in polyimide matrix. Owing to such nanodispersion of sepiolite, the polyimide/sepiolite nanocomposite films exhibit dramatic improvements on the mechanical properties and the coefficient of thermal expansion while fine thermal stability and low water absorption capacity were also maintained. When the sepiolite content increased to 16% the polyimide/sepiolite nanocomposite film achieved as much as 41% and 94% increase on the tensile strength and modulus respectively, and 50% decreased in coefficient of thermal expansion.

Bilayer polyimide film with superparamagnetic response and conductive surface has been exploited as an important candidate for electromagnetic interference shielding material. Poly-imide matrix was derived from 4,4’-oxydianiline and 3,3’,4,4’-benzophenonetetracarboxylic dianhydride. Iron (III) 2,4-pentanedionate (Fe(acac)3) and (1,1,1-trifluoro-2,4-pentadionato) silver(I) (AgTFA) were chosen as magnetic nanoparticles precursor and silver source, respectively. At magnetic polyimide layer, in situ method allowed the Fe(acac) 3 to decompose to γ-Fe2O3, exhibiting typical superparamagnetic response. The conductive surface-silvered poly-imide layer was prepared via in situ single-stage self-metallization technique by thermal curing of the AgTFA-contained poly(amic acid). The reduction of silver(I) and further aggregation of silver atoms gave the conductive polyimide surface. The surface square resistance for the bilayer film of 0.1 Ω/square could be obtained. The structure and the properties of final bilayer f...

Surface silvered polyimide (PI)/Fe2O3 composite films with both superparamagnetic and surface electrically conductive properties have been fabricated by an in situ technique. Iron (III) 2,4-pentanedionate was incorporated into a PI precursor poly(amic acid) solution and thermally decomposed to form iron oxide nanoparticles in the process of thermal imidization, preparing PI/Fe2O3 nanocomposite films. The establishment of a silver layer on the PI/Fe2O3 film surface involved the steps of chemical etching by the alkaline aqueous solution, ion exchange with silver ions and chemical reduction by glucose. The formed Fe2O3 particles of the nano scale endow the film with typical superparamagnetic response. By employing the etching time of only 10 min and a reduction time of no more than 15 min, the well-established silver layers have formed on the upside surface. The corresponding reflectivity and resistivity reached to the value of 76.15% and 0.7 Ω/square respectively.