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With the rapid development of economic globalization and green manufacturing, traditional flexible job shop scheduling has evolved into the low-carbon heterogeneous distributed flexible job shop scheduling problem (LHDFJSP). Additionally, modern smart manufacturing processes encounter complex and diverse contingencies, necessitating the ability to address dynamic events in real-world production activities. To date, there are limited studies that comprehensively address the intricate factors associated with the LHDFJSP, including workshop heterogeneity, job insertions and transfers, and considerations of low-carbon objectives. This paper establishes a multi-objective mathematical model with the goal of minimizing the total weighted tardiness and total energy consumption. To effectively solve this problem, diverse composite scheduling rules are formulated, alongside the application of a deep reinforcement learning (DRL) framework, i.e., Rainbow deep-Q network (Rainbow DQN), to learn the optimal scheduling strategy at each decision point in a dynamic environment. To verify the effectiveness of the proposed method, this paper extends the standard dataset to adapt to the LHDFJSP. Evaluation results confirm the generalization and robustness of the presented Rainbow DQN-based method. [ABSTRACT FROM AUTHOR]

In real-time systems, where tasks have timing requirements, once the workload exceeds the system's capacity, missed due dates may cause system overload. In this situation, finding an optimal scheduling that minimizes the cumulative values of late tasks is critical in both theory and practice. Recently, formalizing scheduling problems as a class of generalized problems, such as Satisfiability Modulo Theory (SMT) and Maximum Satisfiability (MaxSAT), has been receiving immense concern. Enlightened by the high efficiency of these satisfiability-based methods, this paper formulates the single-machine scheduling problem of minimizing the total weight of late tasks as a Weighted Partial Maximum (WPM) Satisfiability problem. In the formulation, scheduling features are encoded as rigidly enforced hard clauses and the scheduling objective is treated as a set of weighted soft ones. Then an off-the-shelf WPM solver is exploited to maximize the total weight of the satisfied soft clauses, provided that all the hard clauses are satisfied. Experimental results demonstrate that, compared with the existing satisfiability-based methods, the proposed method significantly improves the efficiency of identifying the optimal schedule. Moreover, we make minor changes to apply the WPM formulation to parallel-machine scheduling, showing that the proposed method is sufficiently flexible and well scalable. [ABSTRACT FROM AUTHOR]

A new type of insulating–conductive block copolymer was synthesized by metathesis polymerization. The copolymer can self-assemble into unique nanostructures of micelles or hollow spheres. It exhibits a high dielectric constant, low dielectric loss, and high stored/released energy density due to the strong dipolar and nano-interfacial polarization contributions. [ABSTRACT FROM AUTHOR]

Pillararene-containing thermoresponsive polymers are synthesized via reversible addition-fragmentation chain transfer polymerization using pillararene derivatives as the effective chain transfer agents for the first time. These polymers can self-assemble into micelles and form vesicles after guest molecules are added. Furthermore, such functional polymers can be further applied to prepare hybrid gold nanoparticles, which integrate the thermoresponsivity of polymers and molecular recognition of pillararenes. [ABSTRACT FROM AUTHOR]

Haze, generated by floaters (semitransparent clouds, fog, snow, etc.) in the atmosphere, can significantly degrade the utilization of remote sensing images (RSIs). However, the existing techniques for single image dehazing rarely consider that the haze is superimposed by floaters and shadow, and they often aggravate the degree of the haze shadow and dark region. In this paper, a single RSI dehazing method based on robust light-dark prior (RLDP) is proposed, which utilizes the proposed hybrid model and is robust to outlier pixels. In the proposed RLDP method, the haze is first removed by a robust dark channel prior (RDCP). Then, the shadow is removed with a robust light channel prior (RLCP). Further, a cube root mean enhancement (CRME)-based stable state search criterion is proposed for solving the difficult problem of patch size setting. The experiment results on benchmark and Landsat 8 RSIs demonstrate that the RLDP method could effectively remove haze. [ABSTRACT FROM AUTHOR]

Functional polythioether was readily synthesized by cascade oxygen-sulfur exchange reaction (O–S ER) of 2,2,6,6,6-tetramethypiperidin-1-yl)oxy (TEMPO)-contained epoxide with thiocyanate and anionic ring-opening polymerization (AROP) of the in-situ generated episulfide in the protonic solvent and air atmosphere under mild conditions. Polythioether containing TEMPO pendants exhibited red fluorescence by the aggregation-induced emission and the concentration-enhanced emission characteristics, and the red shifts of 10 nm and 70 nm were observed in the UV–vis absorption and fluorescence emission spectra of radical polythioether, respectively, compared to the corresponding radical polyether. Such radical polythioether could also act as the chemical sensor to efficiently detect metal ions and antioxidants based on the strong binding affinity of metal ions and antioxidants to the TEMPO moiety, resulting in reduced fluorescence emission intensity or even complete quenching. Therefore, cascade O–S ER/AROP was proved to be an effective approach for the synthesis of functional polythioether with tunable photophysical properties. A radical polythioether containing TEMPO pendants was directly synthesized by cascade O–S ER/AROP from epoxide, and acted as the chemical sensors to detect metal ions and antioxidants. [Display omitted] • Polythioether containing TEMPO pendants was directly synthesized from epoxide by cascade reaction. • Radical polythioether exhibited red fluorescence by the aggregation-induced emission and the concentration-enhanced emission. • Radical polythioether could act as the chemical sensors to efficiently detect metal ions and antioxidants. [ABSTRACT FROM AUTHOR]

A rare asymmetric bicyclic polymer containing different length of conjugated polyacetylene segments is synthesized by metathesis cyclopolymerization‐mediated blocking‐cyclization technique. The size of each single ring differs from each other, and the unique cyclic polymer topology is controlled by adjusting the feed ratio of monofunctional monomer to catalyst. The topological difference between linear and bicyclic polymers is confirmed by several techniques, and the visualized morphology of asymmetric bicyclic polymer is directly observed without tedious post‐modification process. The photoelectric and thermal properties of polymers are investigated. This work expands the pathway for the derivation of cyclic polymers, and such unique topological structure enriches the diversity of cyclic polymer classes. [ABSTRACT FROM AUTHOR]

Conventional synthetic routes to polythioether usually involve either high energy consumption or potential environmental and health impacts, often accomplished under rigorous conditions. Herein, the oxygen–sulfur exchange reaction (O–S ER) of epoxide and thiocyanate has been successfully combined with aqueous anionic ring-opening polymerization (AAROP) of the in situ generated episulfide, and an unprecedented approach referred to as "cascade O–S ER/AAROP" was established to obtain a well-defined hydroxyl-containing linear polythioether having high molecular weight of 58.6 kDa in an open system at 40 °C. Uniquely, thiocyanate can mediate the O–S ER of epoxide to supply an alkaline circumstance for enhancing the nucleophilicity of sulfanion, and also initiate AAROP of episulfide. The reaction mechanism is revealed by real-time monitoring of the reaction process and tracking pH value of aqueous medium, and further verified by capping and extending the living chain end. Organic ammonium salt can dramatically improve the yield and molecular weight of polythioether with narrow dispersity. This work presents a green strategy where AROP efficiently occurs in water, thereby paving a way to achieving linear poly(hydroxyl thioether) direct from epoxide under mild conditions. [ABSTRACT FROM AUTHOR]

Hyperbranched poly(triazole) with tertiary amine moiety and longer flexible polyethylene glycol (PEG) terminal group ( hb - PTA-PEG ) was synthesized by successive Cu(I)-catalyzed azide-alkyne cycloaddition polymerization, and the corresponding hyperbranched poly(triazolium)s containing hybrid quaternary ammonium ion, [ hb -PTA-PEG ] + [ I ] − and [ hb -PTA-PEG ] + [ TFSI ] − , were obtained after N-alkylation and anion exchange reactions. These hyperbranched polymers presented broad electrochemical stability window of above 6.0 V versus Ag + /Ag and 5.3 V versus Li + /Li, and displayed low glass transition temperature in the range of −13 to −37 °C, owing to the hyperbranched structure combined with the hybrid ionic moiety and longer flexible PEG end-group. The ionic [ hb -PTA-PEG ] + [ TFSI ] − showed superior ionic conductivity, which was above 10 −5 S cm −1 at 30 °C. [ABSTRACT FROM AUTHOR]

In this paper, a novel synthesis of polyethylene glycol (PEG)-modified polypyrrole (PPy) nanomaterials is demonstrated by combining reversible addition-fragmentation chain transfer polymerization and oxidative polymerization. Dye molecules with a heat-labile linker are used as a model drug and covalently anchored onto the PEGlated PPy nanomaterials via 'click chemistry.' The strong absorption of such PPy nanomaterials in the near-infrared region endows the system excellent photothermal effect, which can be used not only as efficient photothermal agents for photothermal therapy but also good controllers of a drug-release system by retro D-A reaction. [ABSTRACT FROM AUTHOR]

Conjugated polyacetylene-based monocyclic and bicyclic polymers were synthesized by blocking-cyclization metathesis polymerization using short ladderphanes as the initial motif and multi-cyclizing unit, and fully characterized to elucidate the cyclic characteristics and good photoelectric properties. Importantly, the molecular topology of rationally designed cyclic polymers was directly observed without a tedious post-modification treatment. [ABSTRACT FROM AUTHOR]

Metathesis cyclopolymerization (MCP)of ionic 1,6-heptadiyne is successfully applied to synthesize polyacetylene(PA) ionomer in different solvents especially in imidazolium-basedionic liquid (IL), and MCP of ionic monomer in the mixture of THF/ILproceeded in a controlled manner by the action of Grubbs second andthird generation catalysts (Ru–II, Ru–III). The influence of catalysts and solvents on polymerization behaviorand chain microstructure was investigated, and the results revealedthat the isolated polymer yield could reach to 97% and 82% by Ru–IIIand Ru–II, respectively,in 1:2 THF/IL after optimization, and PAs incorporating imidazoliumpendent contained ≥95% five-membered-ring structure and almostall trans-double bonds along the backbone. PAs formedin different solvents reflected significant variance in optical absorptionproperties, and a bathochromic shift effect was observed with themixture of THF/IL. [ABSTRACT FROM AUTHOR]

Linear polymers containing pillar[5]arenes as the pendant groups were designed and synthesized via a ring-opening metathesis polymerization. Such polymers could form supramolecular brush polymers and exhibited tunable fluorescence properties based on the host–guest interactions. [ABSTRACT FROM AUTHOR]

Eucommia ulmoides gum (EUG) is composed of trans -1,4-polyisoprene with high flexibility and crystallinity, and could be utilized as elastic and thermoplastic materials. Taking advantage of the unique crystallization characteristics, a series of EUG-based complex elastic fibers were prepared by wet-spinning method using different types of needles. It was found that the EUG fiber displayed excellent mechanical properties including high tensile strength (42.8 MPa), elongation at break (572%), and toughness (136.8 MJ m−3). The complex elastic fibers combining different compositions and various architectures have higher temperature sensitivity and excellent shape memory recovery ability compared to EUG elastomer. Meanwhile, the elastic fibers containing EUG and butyl rubber (IIR) exhibited better damping properties than pristine EUG. Therefore, this work provided a way to enhance the functionality and expand the application of bio-based EUG materials. [Display omitted] • Eucommia ulmoides gum (EUG)-based elastic fibers were prepared by wet-spinning method. • EUG fiber displayed excellent mechanical properties. • The complex elastic fibers with various architectures have better shape memory recovery ability than pristine EUG elastomer. [ABSTRACT FROM AUTHOR]

Eucommia ulmoides gum (EUG) is a bio-based polymer with the structure of trans -1,4-polyisoprene, and easy to crystallize at room temperature, which limits its application in rubbery materials. The epoxidized EUG (E 26 EUG) with an epoxidation degree of 26% was readily prepared and further grafted with different contents of polar perfluoroalkyl groups by ring-opening reaction of epoxy group on the E 26 EUG backbone using perfluorocarboxylic acid as the nucleophilic reagent under mild conditions, affording the modified elastomers E m-x EUG-F x with enhanced mechanical properties, good self-healing performance, and improved damping properties. The vulcanized elastomers VE 26 EUG and VE m-x EUG-F x also exhibited excellent mechanical and damping properties. In addition, a high damping loss value at 0 °C in dynamic mechanical spectra indicated a good wet-skid resistance of the modified EUG elastomers before and after vulcanization. This research is of great significance for extending the applications of functional EUG rubbery materials. [Display omitted] • Eucommia ulmoides gum (EUG) was epoxidized and grafted with different contents of perfluoroalkyl groups. • Perfluoroalkyl-modified EUG elastomers exhibited tunable and enhanced mechanical properties. • Perfluoroalkyl-modified EUG elastomers possessed excellent self-healing performance and improved damping properties. [ABSTRACT FROM AUTHOR]

Based on orthogonal Latin cubes, an image cryptosystem with confusion–diffusion–confusion cipher architecture has been proposed recently (Inf. Sci.2019, 478, 1–14). However, we find that there are four fatal vulnerabilities in this image cryptosystem, which leave open doors for cryptanalysis. In this paper, we propose a reference-validation inference algorithm and design screening-based rules to efficiently break the image cryptosystem. Compared with an existing cryptanalysis algorithm, the proposed method requires fewer pairs of chosen plain-cipher images, and behaves stably since different keys, positions of chosen bits and contents of plain images will not affect the cryptanalysis performance. Experimental results show that our cryptanalysis algorithm only requires   8 × H × W 3 + 3   pairs of chosen plain-cipher images, where H × W represents the image's resolution. Comparative studies demonstrate effectiveness and superiority of the proposed cryptanalysis algorithm. [ABSTRACT FROM AUTHOR]

• We propose Cross-Modal Transformer (CMFormer), a Transformer-based cross-modal semantic segmentation model, which achieves better cross-modal information interaction by capturing long-range contextual dependencies. The CMFormer includes the MS-CAC module and the GFA module, and achieves the state-of-the-art results in RGB-D semantic segmentation task. • We design the MS-CAC module and the GFA module by exploiting the cross-modal properties of Transformer. The MS-CAC module preserves multi-scale information while realizing channel feature correction, while the GFA module realizes spatial feature fusion, and fully considers global and local features, which make the CMFormer achieve better cross-modal information interaction by capturing long-range contextual dependencies. • The effectiveness of the CMFormer is evaluated with extensive experiments on the SOP dataset and NYU Depth v2 dataset. The results show that the CMFormer achieves the state-of-the-art results on both datasets. In the experiment of SOP dataset, CMFormer can achieve 96.74% MPA and 92.98% mIoU. At the same time, the real-time performance of CMFormer can reach 43 FPS(Frames Per Second), which has good real-time performance while meeting the requirements of high precision. Scene understanding in a production workshop is an important technology to improve its intelligence level, semantic segmentation of production workshop objects is an effective method for realizing scene understanding. Since the varieties of information of production workshop, making full use of the complementary information of RGB image and depth image can effectively improve the semantic segmentation accuracy of production workshop objects. Aiming at solving the multi-scale and real-time problems of segmenting the production workshop objects, this paper proposes Cross-Modal Transformer (CMFormer), a Transformer-based cross-modal semantic segmentation model. Its key feature correction and feature fusion parts are composed of the Multi-Scale Channel Attention Correction(MS-CAC) module and the Global Feature Aggregation(GFA) module. By improving Multi-Head Self-Attention(MHSA) in Transformer, we design Cross-Modal Multi-Head Self-Attention(CM-MHSA) to build long-range interaction between RGB image and depth image, and further design the MS-CAC module and the GFA module on the basis of the CM-MHSA module, to achieve cross-modal information interaction in the channel and spatial dimensions. Among them, the MS-CAC module enriches the multi-scale features of each channel and achieve more accurate channel attention correction between the two modals; the GFA module interacts with RGB feature and depth feature in the spatial dimension and fuses global and local features at the same time. In the experiments on the NYU Depth v2 dataset, the CMFormer reached 68.00% MPA(Mean Pixel Accuracy) and 55.75% mIoU(Mean Intersection over Union), achieves the state-of-the-art results. While in the experiments on the Scene Objects for Production workshop dataset(SOP), t he CMFormer achieves 96.74% MPA, 92.98% mIoU and 43 FPS(Frames Per Second), which has high precision and good real-time performance. Code is available at: https://github.com/FutureIAI/CMFormer [ABSTRACT FROM AUTHOR]

Background: Parthenolide (PT), the effective active ingredient of the medicinal plant, feverfew (Tanacetum parthenium), has been used as an anti-inflammatory drug due to its involvement in the inhibition of the NF-кB pathway. Moreover, recent studies have demonstrated the anti-tumor effect of PT in several cancers. However, the effect of PT on esophageal carcinoma remains unclear to date. In this study, we examined the inhibitory effects of PT and its underlying mechanism of action in human esophageal squamous cell carcinoma (ESCC) cells – Eca109 and KYSE-510. Methods: The proliferation ability of Eca109 and KYSE-510 treated with PT was detected using the Cell Counting Kit-8 and colony forming assay. The Transwell assay and the wound healing assay were used to analyze the cell invasion and migration ability, respectively. The tube formation assay was used to investigate the effect of PT on tube formation of endothelial cells. The expression level of NF-кB, AP-1 and VEGF was analyzed by Western blot. Results: We demonstrated that PT attenuates the proliferation and migration ability of ESCC cells in vitro and also inhibits tumor growth in the mouse xenograft model. In addition, PT exhibited anti-angiogenesis activity by weakening the proliferation, invasion and tube formation of endothelial cells in vitro and reduced microvessel density in the xenograft tumors. Further studies revealed that PT reduced the expression level of NF-кB, AP-1 and VEGF in ESCC cells. Conclusion: Collectively, the results of our study demonstrated that PT exerts anti-tumor and anti-angiogenesis effects possibly by inhibiting the NF-кB/AP-1/VEGF signaling pathway on esophageal carcinoma and might serve as a promising therapeutic agent for ESCC. [ABSTRACT FROM AUTHOR]

ABSTRACT The branched triazole group is synthesized by click chemistry via a controlled approach of slow addition of AB2 compound to a B2 core, and used as the substituent for 1,6-heptadiyne monomer. Metathesis cyclopolymerization of monomer is performed well in dichloromethane without the weakly coordinating additive, indicating that the branched triazole itself can stabilize the living propagating chain, to generate branched triazole pendant-contained polyacetylene with trans-double bonds and five-membered ring repeating units along the conjugated backbone. The LiTFSI doped polyacetylenes display ionic conductivities of 2.5-1.8 × 10−6 S cm−1; by further doping with iodine, polyacetylenes show the improved ionic and electronic conductivities of 1.3 × 10−5 and 2.1 × 10−7 S cm−1 at 30 °C, respectively. Therefore, these doped polyacetylenes may act as the new electrolyte materials. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 485-494 [ABSTRACT FROM AUTHOR]

Metathesis cyclopolymerization of mono- or bissubstituted 1,6-heptadiynes is undergone to generate the ionic polyacetylenes (iPAs) with branched 1,2,3-ttriazolium pendants, which possess relatively high intrinsic ionic conductivities of 1.4 × 10−5-2.1 × 10−5 S cm−1 at 30 °C. The doping treatment with lithium bis(trifluoromethanesulfonyl)imide endows iPAs with enhanced ionic conductivities of 2.5 × 10−5-4.3 × 10−5 S cm−1. Further doping with iodine, iPAs show ionic and electronic dual conductivities of 4.5 × 10−5-7.1 × 10−4 and 1.5 × 10−6-4.5 × 10−6 S cm−1, respectively. Therefore, the doped iPAs demonstrate the potential in the area of conducting polymers and polymeric electronics. [ABSTRACT FROM AUTHOR]

In this work, a recyclable electrochemical sensing platform to detect breast cancer susceptibility gene (BRCA) was constructed by pillararenes based host–guest recognition and homogeneous DNA hybridization. BRCA target DNA (T-DNA) formed sandwich-type DNA via homogeneous hybridization with methylene blue labeled signal DNA and alkylamino modified capture DNA, which could form complexes with pillararenes. Such sandwich-type DNA was captured by a novel trithiocarbonate modified pillar[5]arene (P5A-CTA) which was immobilized on the Au electrode. With the help of enzyme amplification, the electrochemical detection signal of target DNA in sensing platform was apparently amplified. This sensing platform exhibited wide linear range and excellent specificity, and was particularly recyclable after simple washing with hot acetonitrile due to the reversible host–guest complexation between P5A-CTA and alkylamino modified DNA. [ABSTRACT FROM AUTHOR]

A series of poly(norbornene-dicarboximide)s with donor–acceptor pendants were synthesized by ring-opening metathesis polymerization, and their photophysical and thermal properties have been investigated. By linking different electron-withdrawing groups to electron-donating tricarbazole on the side chain of poly(norbornene) backbone, the polymers displayed various fluorescence emission color as purplish blue (418 nm), greenish blue (489 nm), green (515 nm), and orange yellow (594 nm). The fluorescence quantum yield of polymer bearing tricarbazole-aldehyde group in CHCl 3 was reached to 0.42. The highest occupied molecular orbital level of polymers was close to −5.3 eV, and the lowest unoccupied molecular orbital varied between −2.34 and −3.02 eV. All polymers exhibited high thermal stability with decomposition temperature exceeding 400 °C. [ABSTRACT FROM AUTHOR]

• Honeycomb-like N-doped porous materials was prepared by hyper-crosslinked reaction. • Pt nanoparticles were fabricated by in-situ pyrolysis reduction strategy. • Pt@3D-NHPC- H 2 O 2 (1.6 nm) show excellent catalytic hydrogenation of cinnamaldehyde in water. • The relationship between morphology and catalytic activity has been explored. The construction of three dimensionally nitrogen-doped honeycomb-like porous carbon (3D-NHPC) materials for metal based heterogeneous catalysts has received substantial attention. However, tailoring these morphologies while retaining catalytic activity and avoiding aggregation of metal nanoparticles (NPs) is still challenging. Herein, we report a synthesis of 3D-NHPC supported Pt NPs (Pt@3D-NHPC (1.6 nm)) through a combination of hyper-crosslinking mediated self-assembly and subsequent in situ pyrolysis reduction. The prepared Pt@3D-NHPC (1.6 nm) catalysts possess a high surface area and hierarchically interconnected porous framework, which can provide more active sites of Pt NPs and short transport paths for substrates. Especially, after a H 2 O 2 post-treatment, the obtained superhydrophilicity of the Pt@3D-NHPC H 2 O 2 (1.6 nm) catalyst presents significant increase of catalytic activity towards efficient hydrogenation of cinnamaldehyde in aqueous solutions. Moreover, owing to the coordination effect by nitrogen-doping and confinement of the porous framework, the as-prepared Pt@3D-NHPC H 2 O 2 (1.6 nm) showed excellent stability and durability. Three dimensionally N-doped honeycomb-like porous carbon supported Pt nanoparticles catalyst was prepared by a combination of hyper-crosslinking mediated self-assembly with a subsequent in situ pyrolysis reduction strategy. The as-prepared multifunctional Pt@3D-NHPC H 2 O 2 (1.6 nm) catalyst is explicitly recognized as an integrating effect involving 3D honeycomb-like structure, superhydrophilicity, and reactant enrichment, which potentially provides inspiring insights for construction N-doped hierarchically porous carbon materials in the chemoselective hydrogenation applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The scene perception of a production workshop is the key to realizing its intelligence. Three-dimensional (3D) instance segmentation based on pure deep learning is an effective method for scene perception, but it is difficult to apply in a production workshop owing to the large number of 3D instance segmentation labels required, which are difficult to collect. This paper proposes a bi-stage multi-modal 3D instance segmentation method that realizes high-precision 3D instance segmentation in the absence of 3D instance segmentation labels. The method has two stages: acquisition of two-dimensional (2D) prior information and instance segmentation of the 3D point cloud. In the first stage, an RGB-D multi-modal fusion instance segmentation network is proposed to solve the problem that similar objects are difficult to distinguish in workshop scenes. In the second stage, accurate 3D instance segmentation is achieved by combining the acquired 2D prior information with correlation filtering algorithms. The performance of the proposed 2D and 3D instance segmentation methods is verified based on a self-built dataset: Scene Objects for Production workshop dataset (SOP). In 2D instance segmentation, compared to the sole reliance on RGB features, the mean average precision (mAP) of the instance segmentation network that incorporates depth features is improved by 3.1, to 72.1; in 3D instance segmentation, when the intersection over union (IoU) threshold is 0.35 and the mAP reaches 80.97. The results indicate that the proposed method realizes accurate perception of workshop objects. [ABSTRACT FROM AUTHOR]

Abstract: On August 29, 2005, Hurricane Katrina made landfall near New Orleans, Louisiana, a major metroplex with petroleum industries. In response to the potential impact of the storm on air quality and to assess the exposures to toxic air pollutants of public health concern, the United States Environmental Protection Agency conducted passive monitoring of air toxics for three months, starting in late October 2005 through early February 2006, at up to 18 sites in the New Orleans area affected by Hurricane Katrina. The overall results of the passive ambient monitoring are summarized with the concentrations for the twenty-nine observed volatile organic chemicals, which include benzene, toluene, ethylbenzene, and xylenes, and the measured concentrations are compared with available health-based screening levels. The results of passive monitoring are also compared with those of the collocated canister sampling at one of the sites. The overall results showed that the outdoor levels of atmospheric volatile organic chemcals in the post-Katrina New Orleans area were very low and far below the available screening levels. The results also confirm the effectiveness of passive monitoring in a large geographical area where conventional methods are not feasible, electrical power is not available, and the need for sampling is urgent, as in the aftermath of natural disasters and other catastrophes. [Copyright &y& Elsevier]

Block copolymers with bipyridyl ligand and metal ion complex were synthesized by ring-opening metathesis polymerization. The combination of high dipolar polarization induced by bis(trifluoromethyl) group in polymer, the long-range polaron hopping process produced by the introduction of metal-bipyridyl side group, and the self-assembled nanostructure significantly improved the dielectric properties of polymers. The iridium(III)-contained block copolymer exhibited outstanding comprehensive dielectric and energy storage performance with high dielectric constant of 23.0–20.3 and low dielectric loss of 0.032–0.013 at 102–106 Hz, and high polarizability of 3.14 μC cm−2 at 280 MV m−1. Besides, the released-stored energy density reached 4.17/4.86 J cm−3 accompanied with the charge-discharge efficiency of 86%. Therefore, it would have potential applications as a metal-organic dielectric material with good dielectric and energy storage properties. [Display omitted] • Block copolymers with bipyridyl ligand and metal complex was synthesized by ROMP. • Ir(III)-contained polymer displayed high dielectric constant of 23 and low dielectric loss of 0.032. • Ir(III)-contained polymer exhibited energy storage density of 4.86 J cm−3 with efficiency of 86%. [ABSTRACT FROM AUTHOR]

Block copolymers with terpyridyl-metal ion pendant were prepared by ring-opening metathesis polymerization, and self-assembled into nanostructure in the selective solvent. The dielectric properties of polymers could be well regulated by adjusting the content of metal ions. The dielectric constant of Ru(II)-contained block copolymer reached high value of 32.5, the dielectric loss was lowered to 0.01 in the frequency range of 100 Hz to 1 MHz, and the energy storage density was up to 5.2 J·cm−3 at the electric field strength of 325 mV·m−1 accompanied with the charge-discharge efficiency of 83.3%, which was attributed to the electronic polarization and interface polarization from the metal ions and nanostructure. Therefore, the introduction of metal ion into the side chain was an effective way to enhance the dielectric and energy storage properties of polymers. [Display omitted] • Block copolymers with terpyridyl-metal ion complex were synthesized by ROMP. • Ru(II)-contained block copolymer displayed high dielectric constant of 32.5 and low dielectric loss of 0.01. • Ru(II)-contained block copolymer exhibited high energy storage density of 5.2 J cm−3 with the efficiency of 83.3%. [ABSTRACT FROM AUTHOR]

Star-shaped poly(ethylene oxide) (PEO) was prepared by atom transfer radical polymerization (ATRP) with a 2-bromoisobutyryl PEO ester as a macroinitiator. Divinylbenzene (DVB) and ethylene glycol dimethacrylate were employed as the coupling reagents. Several factors pertinent to star polymer formation are: type of coupling reagents and solvents, feed ratio of DVB to the macroinitiator, and reaction time. These were studied and used to optimize the star formation process. The optimum yield of star polymer was ca. 90–98%. [ABSTRACT FROM AUTHOR]

Constructing polymeric materials with stretchable and self-healing properties arise increasing interest in the field of tissue engineering, wearable electronics and soft actuators. Herein, a new type of supramolecular cross-linker was constructed through host-guest interaction between pillar[5]arene functionalized acrylate and pyridinium functionalized acrylate, which could form supramolecular polymeric material via photo-polymerization of n-butyl acrylate (BA). Such material exhibited excellent tensile properties, with maximum tensile strength of 3.4 MPa and strain of 3000%, respectively. Moreover, this material can effectively dissipate energy with the energy absorption efficiency of 93%, which could be applied in the field of energy absorbing materials. In addition, the material showed self-healing property after cut and responded to competitive guest. [ABSTRACT FROM AUTHOR]

Sustainable Eucommia ulmoides gum (EUG) was a biomaterial with the molecular structure of trans -1,4-polyisoprene and poor elasticity, and was usually considered as a hard rubber with a limited applications in rubber products. Triazolinedione (TAD)-based Alder-ene reaction was used to modify EUG to precisely tune the mechanical properties and effectively improve the elasticity by reducing crystallinity, introducing urazole groups, and forming hydrogen bonds between EUG molecules. By adjusting TAD feed, the modified EUG could become an excellent tough elastomer with combined high strength, elongation, and toughness; or a unique rubber with superhigh elongation, low Young's modulus, and good elastic recovery rate. Furthermore, the modified EUG displayed enhanced shape memory capability with fast shape recovery speed, high cyclic shape recovery rate after 10-cycle deformations, and large shape memory recoverable deformation. Therefore, these elastomers may have extended applications in tires and smart materials. Image 1 • Sustainable EUG is modified by TAD-based Alder-ene reaction. • TAD-modification enables EUG to be elastomer with improved elastic recovery rate. • Modified EUG exhibits fast shape recovery speed and high shape recovery rate. [ABSTRACT FROM AUTHOR]