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© 2018 Elsevier B.V. Poly (lactic acid) (PLA) is extensively used as an eco-friendly compound for many applications. The synthesis of stereo-pure lactide, specifically L,L-lactide which is the most desired isomer for the synthesis of high-quality PLA is very important. In this work, various materials including MOFs and simple bases have been applied as catalysts for the Lactide synthesis. Herein we report the one-step synthesis of L,L-lactide with high selectivity and yield (99%) in the absence of racemization by applying a cost-effective Cs2CO3 catalyst. The novel described procedure is even expected to be very efficient for industrial applications. ispartof: Catalysis Communications vol:114 pages:33-36 status: published

Tobacco bacterial wilt (TBW) and tobacco black shank (TBS) are two of the most devastating tobacco soil-borne diseases worldwide. In this study, Pseudomonas aeruginosa NXHG29 exhibited dually antagonistic activities against TBW and TBS in vitro assays. Pot experiments were performed to evaluate the capability of a novel bio-organic fertilizer (BOF) consisting of organic fertilizer with NXHG29 to control TBW and TBS. The results showed that application of BOF could more effectively decrease the disease incidence of TBW and TBS than the direct application of NXHG29. Higher amounts of BOF application (0.5% and 1% amendment) resulted in the more suppressive effects on tested pathogens when compared with a low amount of BOF application (0.1% amendment). To determine the antagonistic mechanism of NXHG29, we investigated the colonization pattern of NXHG29 on tobacco roots in a sand system and a natural soil system by tagging NXHG29 with a GFP-marked plasmid. Similar observations were obtained in the two systems. The results indicated that GFP-tagged NXHG29 colonized first the differentiation zones followed by the elongation and maturation zones of the primary roots and subsequently around the junctions of primary and lateral roots. The population dynamics of GFP-tagged NXHG29 on tobacco roots and in the rhizosphere were also monitored. The development of the BOF using dually antagonistic bacteria might provide new options for control strategies, especially with respect to managing both diseases simultaneously in the host plant, which should be more effective in the long term.

Two-dimensional silicon phononic crystals have attracted extensive research interest for thermoelectric applications due to their reproducible low thermal conductivity and sufficiently good electrical properties. For thermoelectric devices in high-temperature environment, the coherent phonon interference is strongly suppressed; therefore phonon transport in the incoherent regime is critically important for manipulating their thermal conductivity. On the basis of perturbation theory, we present herein a novel phonon scattering process from the perspective of bond order imperfections in the surface skin of nanostructures. We incorporate this strongly frequency-dependent scattering rate into the phonon Boltzmann transport equation and reproduce the ultra low thermal conductivity of holey silicon nanostructures. We reveal that the remarkable reduction of thermal conductivity originates not only from the impediment of low-frequency phonons by normal boundary scattering, but also from the severe suppression of high-frequency phonons by surface bond order imperfections scattering. Our theory not only reveals the role of the holey surface on the phonon transport, but also provide a computation tool for thermal conductivity modification in nanostructures through surface engineering. A phonon scattering process on the surface of phononic crystals can explain their ultra-low thermal conductivity. Two-dimensional silicon phononic crystals are promising for thermoelectric applications, as the periodic arrangement of holes allows for significant reduction of their thermal conductivity. A team from Hunan University of Science and Technology and Xiangtan Universities in China, and the Institute of High Performance Computing in Singapore, manage to model the values reported experimentally by incorporating a phonon scattering mechanism, rooted to the bond imperfection on the surface of the nanostructure. As the bonds towards the surface grow shorter and therefore stronger, they perturb the local potential, and suppress the high-frequency phonons. Low-frequency phonons, on the other hand are suppressed by normal boundary scattering. The authors conclude that these two actions lead to the ultra-low thermal conductivity values, and predict that further reduction can be achieved by roughening the hole walls in the phononic crystal.

A novel endophytic actinobacterium, designated strain EGI 6500139T, was isolated from the surface-sterilized roots of Anabasis aphylla L., collected from Xinjiang, northwest PR China, and subjected to polyphasic taxonomic characterization. Strain EGI 6500139T formed sparse aerial mycelium with rod-like spores. Whole-cell hydrolysates of the isolate contained meso-diaminopimelic acid as the cell-wall diamino acid, glucose as major sugar, and mannose, galactose, xylose and ribose as minor sugars. The polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, one unidentified glycolipid, one unidentified phospholipid and four unidentified polar lipids. The major fatty acids identified were anteiso-C17 : 0, anteiso-C15 : 0, iso-C15 : 0 and iso-C16 : 0. The predominant menaquinones detected were MK-11 and MK-11(H2). The G+C content of the genomic DNA of strain EGI 6500139T was 70.4 mol%. Strain EGI 6500139T showed the highest 16S rRNA gene sequence similarity to Glycomyces lacisalsi XHU 5089T (96.3 %). Phylogenetic analysis showed that strain EGI 6500139T fell within the clade of the genus Glycomyces , and formed a clade with G. lacisalsi XHU 5089T and G. albus CCTCC AA 2013004T. Based on phenotypic, chemotaxonomic and phylogenetic data, strain EGI 6500139T represents a novel species of the genus Glycomyces , for which the name Glycomyces anabasis sp. nov. (type strain EGI 6500139T=JCM 30088T=KCTC 29495T) is proposed.

A Gram-stain-positive, alkaliphilic bacterium, designated EGI 80668T, was isolated from a Tamarix cone soil in Xinjiang, north-west China. Cells were facultatively anaerobic, terminal endospore-forming and motile by means of peritrichous flagella. Colonies were yellowish and the cells showed oxidase-negative and catalase-positive reactions. Strain EGI 80668T grew at pH 8.0–10.0 and with 0–10 % (w/v) NaCl (optimally at pH 9.0 and with 1–2 % NaCl) on marine agar 2216. The predominant menaquinone was MK-7. The major fatty acids were anteiso-C17 : 0 and anteiso-C15 : 0. The cellular polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, four unknown phospholipids and one unknown aminophospholipid. The G+C content of the genomic DNA was 38.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain EGI 80668T was affiliated to the genus Bacillus . The highest 16S rRNA gene sequence similarity between strain EGI 80668T and a member of the genus Bacillus was 96.83 % with Bacillus cellulosilyticus JCM 9156T. A polyphasic taxonomic study based on morphological, physiological, biochemical and phylogenetic data indicated that strain EGI 80668T represents a novel species of the genus Bacillus , for which the name Bacillus tamaricis sp. nov. (type strain EGI 80668T=KCTC 33703T=CGMCC 1.15917T) is proposed.

While the role of negatively charged axial ligands (e.g. Cl−, Br− and I−) in tuning the reactivity and stability of molecular Ru water oxidation catalysts was well-documented, less was explored when axial ligands are neutral molecules. In this work, we reported the synthesis and full characterization of [Ru(NCNHCO)(bpy)L]+ complexes (L = DMSO, 1; L = 4-picoline, 2), where L is a neutral axial ligand. The effects of these axial ligands on the stability and reactivity of the catalysts were thoroughly investigated. Both complexes were competent to oxidize water with turnover numbers up to 463 and 107, respectively. Complex 1 initiated the water oxidation involving a PCET process. It was found that complex 2 afforded its corresponding Ru–aqua complex owing to the carboxylate dissociation, while complex 1 exhibited considerable stability in acidic aqueous solutions. On the other hand, in the presence of an oxidant, for complex 1 DMSO/H2O exchange occurred, facilitating water oxidation. In contrast, the Ru–O bond cleavage of complex 2 was inhibited, leading to an inferior catalytic performance.

High-quality zeolite imidazole frameworks (ZIF-8, ZIF-67, and bimetallic Zn/Co-ZIF) were synthesized using the spray-drying technique and the mechanism of crystal growth during the whole process is discussed. It is also demonstrated that the crystallization mechanism for N-donor containing ditopic imidazolate (IM) ligands forming ZIF structures is divergent from MOF formation applying carboxylate ligands, and their formation using the spray dry method occurs via a unique mechanism. An intermediate amorphous phase was obtained after spray drying the feed solution, and the crystallographic ZIF structure was obtained during immersion in a solvent. Several characterization techniques, such as FTIR, XRD, SEM, porosity analysis, elemental analysis etc., were applied to examine the characteristic properties of materials, including, intermediate compounds and final products. The results proved that the spray drying procedure is a facile, continuous and effective synthetic route to produce MOFs (ZIFs) in higher quantities with high-quality properties such as high porosity, a large surface area, more active catalyst sites, etc. applying a minimum amount of time and energy which is unusual in common synthesis methods of MOFs.

The die roll of fine-blanking parts is an important indicator when evaluating quality of parts. In this paper, the formation of die roll during the punching process is analyzed through the difference of the velocity of material between the die roll area and center area. At first, an assumption is made that every die roll is determined by the volume proportion of the part and waste area in the circular affected zone, and it is proved by simulation. In addition, the introduction of insertion block can prevent the fracture on the shearing surface without V-ring. In consideration of waste affect area and insertion block, a novel combined method is designed to decrease the die roll. It turns out that the height of die roll can be reduced by as much as 70% in both FEM simulation and actual experiment, which shows a great potential in fine-blanking industry.

Metal–organic polyhedra (MOPs) have attracted great interest in the past decade. As a new series of nano-material, MOPs have high outer and inner specific surface areas and are able to be applied in different areas such as catalysis, gas sequestration, drug delivery, molecule sensing, etc. In this review, the focus is made on the design and synthetic strategies approaching edge-bridged tetrahedra MnL6 and face-capped tetrahedra MnL4. Besides the synthesis, structure, and properties of tetrahedral self-assemblies are also considered, while tetrahedra will be compared with other complicated multinuclear constructions. The discussion of how the properties of tetrahedral cages can be altered by varying employed subcomponents is made. Moreover, the multifarious host–guest system and behavior of metal–organic tetrahedral self-assemblies for catalytic applications are addressed in details.

This paper proposes a binocular holographic floating display. The device consists of two phase-modulation spatial light modulators (SLM) and a dihedral corner reflector array (DCRA) element. The conjugate images of the SLMs generated by the DCRA become the system’s exit pupils. Exit pupils that are larger than the pupils of human eyes are arranged to locate at the position of observer's eyes. Therefore, the dimension of the SLM will not limit the viewing angle, although the pixel pitch of the SLM still limits the maximum field of view. For the laser light source, the resolution of the images can achieve 3 arc minutes when the distance between images and DCRA is less than 20 cm. The full-color display function is also performed in the proposed device.

China commits its goal of peak carbon dioxide emissions before 2030 and achieving carbon neutrality before 2060. The integrated energy system (IES) is one of the critical approaches to achieving the commitments. While the prevailing evaluation method for calculating the carbon emissions of IES neglected parts of factors influence, the result could not reflect the carbon emissions comprehensively. Considering the insufficiency above, in this paper, the evaluation method of carbon emission based on the whole life cycle of IES is proposed. First, based on the IES energy hub model, a typical park’s carbon emission model has been established. Then, the carbon emission coefficients of energy and equipment in production, transportation and operation are analysed, respectively. Hence, a low-carbon operation optimisation model of the IES is proposed. Later, with the lowest annual carbon emission of the integrated energy system as the optimisation target, the IES’s optimal carbon emission allocation and operation plan are proposed, based on the balance between energy supply and demand in the process of energy and equipment use and operation. As a result, the carbon emission of the IES of the park reduces effectively.

The mimicking of both homosynaptic and heterosynaptic plasticity using a high-performance synaptic device is important for developing human-brain-like neuromorphic computing systems to overcome the ever-increasing challenges caused by the conventional von Neumann architecture. However, the commonly used synaptic devices (e.g., memristors and transistors) require an extra modulate terminal to mimic heterosynaptic plasticity, and their capability of synaptic plasticity simulation is limited by the low weight adjustability. In this study, a WSe2 -based memtransistor for mimicking both homosynaptic and heterosynaptic plasticity is fabricated. By applying spikes on either the drain or gate terminal, the memtransistor can mimic common homosynaptic plasticity, including spiking rate dependent plasticity, paired pulse facilitation/depression, synaptic potentiation/depression, and filtering. Benefitting from the multi-terminal input and high adjustability, the resistance state number and linearity of the memtransistor can be improved by optimizing the conditions of the two inputs. Moreover, the device can successfully mimic heterosynaptic plasticity without introducing an extra terminal and can simultaneously offer versatile reconfigurability of excitatory and inhibitory plasticity. These highly adjustable and reconfigurable characteristics offer memtransistors more freedom of choice for tuning synaptic weight, optimizing circuit design, and building artificial neuromorphic computing systems.

Excited states in the odd-A nucleus 71Ga have been studied via the 70Zn(7Li, )71Ga fusion-evaporation reaction with incident beam energies of 30 and 35 MeV. The level scheme is established up to spin = (29/2+) and an excitation energy 6.6 MeV. A previously known sequence built on the 9/2+ state is extended as a novel rotational band originating from the alignment. Furthermore, a negative-parity sequence is also reported. The observed energy levels of 71Ga have been interpreted in the framework of the nuclear shell model (SM).

The paper has taken a fly ash of power plant in southern China as the research object, in view of the fly ash were modified, the research of the modified fly ash on the experimental study of nuclide uranium adsorption of uranium tailings. A modified fly ash and B modified fly ash were prepared with a-zeolite while using Na2CO3 and NaOH as intercalated material respectively. By changing the pH, initial U(VI) ions concentration, temperature of environment, and contact time, the best conditions of adsorption was selected out. By comparing the properties of two different modified fly ash composites, it is not difficult to find that the theoretical adsorption capacity of U(VI) is higher and the removal rate of U(VI) is higher than that of U(VI). Therefore, modified fly ash B had a better adsorption performance.

A 2 × 4 -cell superconducting linac module for the THz-FEL facility has been developed at the China Academy of Engineering Physics, which is expected to provide 6–8 MeV quasi-CW electron beams with an average current of 1–5 mA. The module consists of two 4-cell SRF cavities, two main couplers, two tuners and a cryostat. The design, fabrication and performance test of these components is presented in this paper. The test results reveal that all these components have reached their design goals and the module has also been assembled and horizontal tested at Chengdu. The gradients of both cavities at 2 K reach 10 MV/m, which meets our requirements. Currently beam-loading commissioning is underway.

Biogas is a renewable fuel source of methane that can be used as energy for vehicles after a purification process to remove impurities (Biogas upgrading and cleaning). However, removal of CO2 from methane is one of the critical steps for biogas upgrading and is limiting its commercial application. An overview of the materials in technologies of separation (membrane) and sorption (sorbents) know-how, including chemisorbents and physisorbents, has been made with a particular emphasis on biogas upgrading. The alternative properties and possibilities of different technologies and materials for CO2 separation, including alkanol amine, solid alkanol amine, zeolites, carbonaceous, metal-organic frameworks (MOFs), zeolitic imidazolate frameworks (ZIFs), and membrane applied for purifying raw biogas (upgrading) to produce bio-methane and on the other hand, to reduce CO2 emission from fossil fuel are discussed in this review.

The defect formation in metal–organic frameworks (MOFs) initiated by the crystal growth-rate of different synthesis procedures affects the structure, morphology and other properties of MOFs such as particle shape, gas adsorption capacity and specifically catalytic performance etc. Although the design of defect structures and the defect structures itself are well known, comparatively little is known regarding defect creation introduced by the synthesis procedure (different from mixed-linker approach, the use of acid modulators, post-synthetic treatment, etc.) and characterization of the resulting naturally occurring abnormalities (defects) in the material. Moreover, high performance of MOFs in various catalytic reactions can be correlated to the higher amount of defect structures because defects can possibly exhibit acid and/or basic properties. While studies of MOF crystallinity confirmed that for a given type of MOF different synthesis methods generate samples of similar crystal structures, their morphologies are often different due to the differences in the crystallization rates associated with these methods.

A series of metal organic frameworks (MOFs) MDABCO (M = Co, Ni, Cu, Zn; DABCO = 1,4-diazabicyclo[2.2.2]octane) are utilized as catalysts for the bulk ring-opening polymerization of l -lactide. The catalytic activity varies in the order CuDABCO, NiDABCO

A dinuclear ruthenium complex [RuII(NCNHCO)(pic)2]22+ (2) was firstly prepared and characterized spectroscopically and electrochemically. Instead of the conventional ligand exchange, complex 2 dissociates in-situ to afford two single-site Ru aqua complexes, [RuII(OH2)(NCNHCO)(pic)2]+, which mediates water oxidation through proton-coupled electron transfer events. In electrokinetic studies, complex 2 demonstrated a TOF of 150.3 s-1 comparable to those state-of-the-art catalysts at neutral conditions. TONs of 2173 and 217 were attained in chemical and photochemical water oxidation when 2 was used as a catalyst, exhibiting good stability. Notably, a TOF of 1.3 s-1 was achieved at CAN-driven water oxidation, which outper-formed most of the reported single-site Ru complexes, indicating that complex 2 is one of most active water oxidation catalysts (WOCs) to date. The unique coordination configuration and outstanding catalytic perfor-mance of complex 2 might shed light on the design of novel molecular WOCs.

A series of high-quality M2(BDC)2(DABCO) metal-organic frameworks (abbreviated as M-DABCO; M=Zn, Co, Ni, Cu; BDC=1,4-benzene dicarboxylate; DABCO=1,4-diazabicyclo[2.2.2]octane), were synthesized by using a solvothermal (SV) method, and their catalytic activity for the cycloaddition of CO2 to epoxides in the absence of a co-catalyst or solvent was demonstrated. Of these metal-organic frameworks (MOFs), Zn-DABCO exhibited very high activity and nearly complete selectivity under moderate reaction conditions. The other members of this MOF series (Co-DABCO, Ni-DABCO, and Cu-DABCO) displayed lower activity in the given sequence. Samples of Zn-DABCO, Co-DABCO, and Ni-DABCO were recycled at least three times without a noticeable loss in catalytic activity. The reaction mechanism can be attributed to structural defects along with the acid-base bifunctional characteristics of these MOFs. Moreover, we illustrate that the synthetic method of M-DABCO influences the yield of the reaction. In addition to the SV method, Zn-DABCO was synthesized by using spray drying due to its industrial attractiveness. It was found that the synthesis procedure clearly influenced the crystal growth and thus the physicochemical properties, such as surface area, pore volume, and gas adsorption, which in turn affected the catalytic performance. The results clarified that although different synthetic methods can produce isostructural MOFs, the application of MOFs, especially as catalysts, strongly depends on the crystal morphology and textural properties and, therefore, on the synthesis method.

Recently, additive manufacturing is one of the most focused research topics due to its explosive development, especially in manufacturing engineering and medical science. In order to build 3D complex scaffolds with multi-biomaterials for clinical application, a new 3D multi-nozzle system with dual-mode drives, i.e. ejection and extrusion was developed. In this paper, much effort was made to gain fine control of droplet and excellent coordination during fabrication. Specifically, the parameters that influence the size and stability of droplet most was intensively studied. Considering that the biomaterials used in the future may have much difference in properties, the combination of parameters was investigated to facilitate the settings for certain-sized droplets, which are potentially eligible for bio-printing. The dispensing nozzles can work well both in independent and convergent mode, which can be freely switched. Outstanding to the most currently used 3D bio-printing techniques, this system can fabricate scaffolds with multimaterials of both low viscosity (by pneumatic dispensing) and high viscosity (through motor extrusion). It is highly expected that this system can satisfy clinical application in the near future.

Schisandrin B (Sch B), a dibenzocyclooctadiene lignan isolated from Schisandra chinensis (Turcz.) Baill, has been shown to have anti-inflammatory effect. The purpose of this study was to evaluate the effect of Sch B on LPS-induced inflammation in microglia and to investigate the molecular targets of Sch B. BV2 cells were stimulated by LPS in the presence or absence of Sch B. The results showed that the levels of TNF-α, IL-6, IL-1β, and PGE2 upregulated by LPS were significantly suppressed by Sch B. LPS-induced NF-κB activation was also inhibited by Sch B. Furthermore, Sch B was found to upregulate the expression of PPAR-γ in a concentration-dependent manner. In addition, the inhibition of Sch B on TNF-α, IL-6, IL-1β, and PGE2 production were reversed by PPAR-γ antagonist GW9662. In conclusion, these results suggested that Sch B inhibited LPS-induced inflammatory response by activating PPAR-γ.

A direct synthesis of pillared metal-organic frameworks with Kagome net topology under mild conditions (room temperature and ambient pressure) was developed which provides a straightforward and energy-saving procedure to produce MOFs. A series of metals (M = Zn, Ni and Co) bridging with ligands 1,4-benzene dicarboxylate (bdc) and 1,4-diazabicyclo[2.2.2]octane (dabco) were used to construct MOF frameworks denoted as M 2 (bdc) 2 (dabco). The Kagome net pillared structures were confirmed via crystal phase analysis (XRD). The use of different metals resulted in diverse crystal morphologies and particle shapes as observed from scanning electron microscope analysis (SEM). The obtained Kagome net pillared structure influences the physical properties such as surface area, pore size, N 2 /CO 2 /CH 4 gas adsorption and also thermal stability. Furthermore, modeling was applied to determine the behavior of the isosteric heat of adsorption on CO 2 and gas selectivity of CO 2 /CH 4 and CO 2 /N 2 .

A green, simple and low cost process for production of well dispersed, small size silver nanoparticles with narrow distribution from 3 nm to 15 nm was described. In this method, silver nanoparticles were prepared in aqueous medium by employing wolfberry fruit extract as both reducing and stabilizing agent without utilizing any other capping and reducing agent. The generation of metallic nanoparticles was observed by change of color and the UV–vis absorption spectroscopy. The obtained silver nanoparticles were analyzed by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results show that the as-synthesized silver nanoparticles are highly crystalline in nature, spherical in shape. The reaction times, silver nitrate concentrations and wolfberry fruit extract amounts play crucial roles in the synthesis of small silver nanoparticles. The method displayed in this paper offers a very hopeful mean to prepare other noble nanoparticles using renewable materials as reducing and capping agent.

A novel endophytic bacterium, designated strain EGI 6500252T, was isolated from the surface-sterilized roots of a medicinal plant (Capparis spinosa L.) collected from Urumqi city, Xinjiang, north-west China. Cells were Gram-stain-positive, non-motile, aerobic, catalase- and oxidase-positive, rod-shaped and did not display spore formation. Strain EGI 6500252T grew at 10–40 °C (optimum 25–30 °C), at pH 6.0–8.0 (optimum pH 7.0) and in the presence of 0–10 % (w/v) NaCl (optimum 0–3 %). The major cellular fatty acids (>10 %) were identified as iso-C15 : 0, anteiso-C15 : 0, anteiso-C17 : 0 and summed feature 4. The predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four unknown phospholipids, one unknown glycolipid and one unknown lipid. The dominant isoprenoid quinone was menaquinone 7 (MK-7). The DNA G+C content was 39.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain EGI 6500252T belonged to the genus Bacillus , and exhibited a highest 16S rRNA gene sequence similarity (96.2 %) that was lower than the suggested threshold (97.0 %) for separating bacterial species. On the basis of the phylogenetic analysis, chemotaxonomic data and physiological characteristics, strain EGI 6500252T represents a novel species of the genus Bacillus , for which the name Bacillus capparidis sp. nov. is proposed. The type strain is EGI 6500252T (=CGMCC 1.12820T=KCTC 33514T).

A novel Zn/Co zeolitic imidazolate framework (ZIF) has been constructed by an easy and straightforward room temperature technique. Several characterization techniques such as SEM, TEM-EDX, single-crystal XRD and ICP have been applied to confirm that the structure formed is a sodalite (SOD) cage type structure. The Zn/Co-ZIF possesses a high nano-crystallinity and porosity with a large surface area. By tuning the amount of Co and Zn in the Zn/Co zeolitic imidazolate framework, the physical and chemical properties have been improved compared with those of the single metal frameworks (ZIF-8 and ZIF-67). Consequently, the Zn/Co-ZIF was investigated for two different applications; gas adsorption (CO2, CH4 and N2) and catalysis (CO2 conversion to cyclic carbonates) and the obtained results were compared with the performance of previously reported single metal frameworks (ZIF-8 and ZIF-67). Additionally, hydrolytic stability tests under ambient conditions and immersed in water at 75 °C were performed and pointed out that Zn/Co-ZIF exhibits a higher stability. Moreover, based on these results, the Zn/Co-ZIF demonstrates better properties compared with ZIF-8 and ZIF-67.

Incorporation of negatively charged moieties into complexes is a promising strategy to develop water oxidation catalysts with high stability and low over-potentials. We reported here the synthesis of a novel pincer-type ligand precursor, 1-(pyridin-2-ylmethyl)-3-methylcarboxylate-imidazolium (1). Deprotonation of C2-H of 1 resulted in formation of NCNHCO, a negatively charged asymmetric N-heterocyclic carbene (NHC). Complexes [Ru(NCNHCO)(terpy)]+ (2) and RuCl(NCNHCO)(DMSO)(pic) (3) were prepared and capable of decomposing water chemically and photo-chemically. Under acidic conditions, 4-picoline/H2O exchange in 3 was detected by UV-vis and 1H NMR, forming the corresponding Ru–aqua complex. In a typical three-component light-induced water oxidation, a turnover number of 273 was attained employing 3, which demonstrated catalytic ability comparable to those state-of-the-art catalysts.

To improve the biological performance of hydroxyapatite scaffolds in bone tissue engineering, graphite was used as porogen to create additional micro/nanoporosity to macroporosity, resulting in hierarchical porosity. For maximum imitation of natural bone structures, scaffolds with different porosity features were fabricated using micron/nano-sized graphite. The sintering profile of graphite treated scaffolds was optimised to reduce the influence of shrinkage. To confirm the porosity features, the micro/nanostructures of scaffolds were characterised by scanning electron microscopy and Brunauer-Emmett-Teller method. Considering that hydroxyapatite is resistant to biodegradation in vivo, the degradation rate of scaffolds in modified simulated body fluid was examined. Furthermore, biological evaluations based on myoblasts were carried out to investigate the influence of porosity features on the essential performance such as adhesion, proliferation and differentiation. The results indicate that the scaffolds with dominant microporosity and little nanoporosity formed inside had high potential for clinical applications due to improved performance in bioactivity.

Named entity disambiguation (NED) is the task of linking mentions of ambiguous entities to their referenced entities in a knowledge base such as Wikipedia. We propose an approach to effectively disentangle the discriminative features in the manner of collaborative utilization of collective wisdom (via human-labeled crowd labels) and deep learning (via human-generated data) for the NED task. In particular, we devise a crowd model to elicit the underlying features (crowd features) from crowd labels that indicate a matching candidate for each mention, and then use the crowd features to fine-tune a dynamic convolutional neural network (DCNN). The learned DCNN is employed to obtain deep crowd features to enhance traditional hand-crafted features for the NED task. The proposed method substantially benefits from the utilization of crowd knowledge (via crowd labels) into a generic deep learning for the NED task. Experimental analysis demonstrates that the proposed approach is superior to the traditional hand-crafted features when enough crowd labels are gathered.

Biomethane is one of the biofuel sources produced from biogas which is an important source of renewable energy. Since it is an alternative and clean energy source, its implementation as fuel source applying established energy infrastructure is an attractive opportunity. However, biogas as a source of biomethane contains undesirable compounds, e.g., H2S, NH3, siloxanes, water, etc. and needs to be decontaminated before usage. Biogas cleaning technologies are presented from a material point of view along with their property modifications. A brief discussion of materials applied in technologies with a particular emphasis on biogas cleaning is followed by the alternative properties and possibilities of liquid and solid adsorbents as well as chemical reactions used for biogas cleaning to produce biomethane suitable as fuel source to replace or reduce fossil fuel consumption.

In article number 1900213, Ye Zhou, Su‐Ting Han, and co‐workers demonstrate a photo‐induced transition from oxygen vacancy filament to metal filament in the heterostructure of titanium oxides/graphene. A voltage controlled negative differential resistance effect is also obtained. This will provide significant insight into the design and manipulation of memristive devices based on heterostructured materials.

A Gram-stain-negative, aerobic, non-motile and rod-shaped bacterium, designated strain X7XT, was isolated from a rhizosphere soil sample of Nicotiana tabacum L. collected from a tobacco factory located in Kunming, south-western China. The cells showed oxidase-positive and catalase-positive reactions. Growth occurred at 20–40 °C and pH 6.0–8.0, with optimal growth at 30 °C and pH 7.0. The predominant respiratory quinone was MK-7. The major fatty acids were identified as iso-C15 : 0, iso-C17 : 0 3OH and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c). The cellular polar lipids contained phosphatidylethanolamine, an unidentified aminophospholipid, two unidentified glycolipids, four unidentified aminolipids and four unidentified lipids. The genomic DNA G+C content was 49.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain X7XT should be affiliated to the genus Flavisolibacter . Results from further analysis showed that strain X7XT had highest 16S rRNA gene sequence similarity to Flavisolibacter metallilatus TX0661T (96.4 %) and ‘ Flavisolibacter swuensis ’ SR2-4-2T (96.4 %), followed by other species of the genus Flavisolibacter . The polyphasic taxonomic characteristics indicated that strain X7XT represents a novel species of the genus Flavisolibacter , for which the name Flavisolibacter nicotianae sp. nov. (type strain X7XT=KCTC 62326T=CGMCC 16451T) is proposed.

Depending on the mobile species involved in the resistive switching process, redox random access memories and conductive bridge random access memories are widely studied with distinct switching mechanisms. Although the two resistance switching types have faithfully proved to be electrochemically linked in metal oxide‐based memristive devices, the corresponding photo‐induced transition has not yet been realized. Here, a photo‐induced transition through the integration of a graphene layer into a titanium oxide‐based memory device is demonstrated. Coupled with Raman mapping and an electron energy loss spectroscopy technique, the photo‐induced interaction at the heterostructure of graphene/titanium oxide are considered to dominate the transition process. Moreover, a negative differential resistance effect is observed by controlling the applied voltage, which can be credited to the saturation of trap centers (oxygen vacancies) and the increase of interfacial barrier at the graphene/titanium oxide heterojunction.

There has always been an intimate connection between visual text and nationalism. Visual symbols, for example, territory maps, national totems, and leaders’ images, become essential resources for the establishment of territory boundaries, collective identity, and social mobilization of the imagined community. In contemporary China, nationalism and identity politics have been core issues entangled with China’s modernity. Traditional research on nationalism has focused on influence from nations, governments, and elites. Nationalism is used by elites as a tool to actuate the public, achieve national independence, enhance the legitimacy of their regime, or set public agendas. Treating cyber-nationalism as a kind of narrative discourse includes information flow, topic discussion, identity construction, and action organization of nationalism. Most research concentrated on textual discourse while ignoring visual expression. Visual expression has long been an essential part of China’s nationalism. During revolutionary times, visual publicity like woodcuts and posters became a crucial method to motivate people and eliminate illiterates.

MXenes have drawn considerable attention in both academia and industry due to their attractive properties, such as a combination of metallic conductivity and surface hydrophilicity. However, to the best of our knowledge, the potential use of MXenes in non-volatile resistive random access memories (RRAMs) has rarely been reported. In this paper, we first demonstrated a RRAM device with MXene (Ti3C2) as the active component. The Ti3C2-based RRAM exhibited typical bipolar switching behavior, long retention characteristics, low SET voltage, good mechanical stability and excellent reliability. By adjusting different compliance currents in the SET process, multi-state information storage was achieved. The charge trapping assisting hopping process is considered to be the main mechanism of resistive switching for this fabricated Ti3C2-based RRAM, which was verified by conductive atomic force microscopy (C-AFM) and Kelvin probe force microscopy (KPFM). Moreover, this flexible Ti3C2-based RRAM, with good mechanical stability and long retention properties, was successfully fabricated on a plastic substrate. Ti3C2-based RRAMs may open the door to additional applications and functionalities, with high potential for application in flexible electronics.

An arsenic-resistant strain, CB3T, was isolated from arsenic-rich aquifers at the Jianghan Plain in Hubei, China. Phylogenetic and biochemical analysis suggested that it should represent a new species of the genus Pseudaminobacter in the family Phyllobacteriaceae. The 16S rRNA gene of CB3T shared the highest sequence similarities to those of the type strains Pseudaminobacter defluvii THI 051T (97.8 % identity) and Pseudaminobacter salicylatoxidans BN12T (97.4 %). The DNA–DNA relatedness values of CB3T with respect to strains belonging to the genus Pseudaminobacter were less than 70 %. The fatty acid profile of CB3T consisted of C16 : 0, cyclo-C19 : 0 ω8c and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) as major components. The major polar lipids were phosphatidylcholine, phosphatidylglycerol, phosphatidyldimethylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylethanolamine and diphosphatidylglycerol. The DNA G+C content was 61.4 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain CB3T was distinct from previously described Pseudaminobacter species. Therefore, we propose that strain CB3T represents a novel species of the genus Pseudaminobacter, Pseudaminobacter arsenicus sp. nov., strain CB3T (=CCTCC AB2016116T=KCTC 52625T) is designated as the type strain.

A Gram-stain-negative, aerobic, rod-shaped bacterium, designated strain C8-1T, was isolated from the rhizosphere soil of Nicotiana tabacum L. collected from Kunming, south-west China. The cells showed oxidase-positive and catalase-positive reactions. Growth was observed at 10–40 °C, at pH 6.0–8.0 and in the presence of up to 1 % (w/v) NaCl, with optimal growth at 30 °C and pH 7.0. The predominant isoprenoid quinone was Q-8. The major fatty acids were identified as iso-C15 : 0, iso-C17 : 0 and iso-C17 : 1ω9c. The cellular polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, five unidentified phospholipids and two unidentified aminophospholipids. The genomic DNA G+C content was 70.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain C8-1T should be assigned to the genus Lysobacter . 16S rRNA gene sequence similarity analysis showed that strain C8-1T was closely related to Lysobacter cavernae YIM C01544T (98.6 %), Lysobacter soli DCY21T (97.6 %), Lysobacter panacisoli CJ29T (97.3 %), Lysobacter firmicutimachus PB-6250T (97.3 %), Lysobacter niastensis GH41-7T (97.3 %) and Lysobacter gummosus KCTC 12132T (97.1 %). DNA–DNA hybridization data indicated that the isolate may represent a novel genomic species belonging to the genus Lysobacter . Polyphasic taxonomic characteristics indicated that strain C8-1T represents a novel species of the genus Lysobacter , for which the name Lysobacter tabacisoli sp. nov. is proposed. The type strain is C8-1T (=KCTC 62034T=CGMCC 1.16271T) .

In view of the problem that the old approach of determining the sample size is too rough and the test sample size is too large, a reasonable application of information entropy method is proposed to obtain the test data of the equipment system by fusing the prior information of each unit of the equipment system. The testability indexes of the prior distribution are obtained, the fault sample size and the test scheme are further determined by Bayes posterior risk criterion. The test data of an electric actuator system’s module is taken as an example and the failure detection rate is adopted as the test index, the fault sample size is reduced by 86.5%, and the test index error is figured out as 0.75% compared with the classical test through analysis and calculation, reduce the test cost and guarantee the credibility.

Additive manufacturing or three-dimensional (3D) printing technology is increasingly being employed in biochemical as well as clinical applications and more importantly in fabrication of microfluidic devices. However, the microfluidic community mainly relies on photolithography for fabrication of a defined mask, which is both tedious and expensive requiring clean room settings as well as limited to the generation of two-dimensional features. In this work, we 3D printed nanoclay-reinforced Pluronic ink as a sacrificial material, which exhibited shear thinning behavior and superior printability allowing the fabrication of unsupported or overhanging templates of channels with uniform diameter and circular cross-sections. To highlight the potential and effectiveness of the presented approach, we fabricated a human blood vessel-on-a-chip model with curved as well as straight channels. These channels were then lined up with human umbilical vein endothelial cells (HUVECs) and subjected to a dynamic culture for 10 d to explore the effect of shear stress on HUVEC morphology based on the location of HUVECs in the devices. Overall, we presented a highly affordable, practical and useful approach in manufacturing of polydimethylsiloxane-based devices with closed microfluidic channels, which holds great potential for a numerous applications, such as but not limited to organ-on-a-chip, microfluidics, point-of-care devices and drug screening platforms.

One of the most effective approaches to solving the current problem arising from the von Neumann bottleneck in this period of data proliferation is the development of intelligent devices that mimic the human learning process. Information sensing and processing/storage are considered to be the essential processes of learning. Therefore, high-performance sensors, memory/synaptic devices, and relevant intelligent artificial tactile perception systems are urgently needed. In this regard, innovative device concepts and emerging two-dimensional materials have recently received considerable attention. Herein, we discuss the development of MXenes for applications in tactile sensors, memristors, and artificial tactile perception systems. First, we summarize the structures, common properties, and synthesis and assembly techniques of MXenes. We then discuss the applications of MXenes in tactile sensors, memristors, and relevant neuromorphic-based artificial tactile perception systems along with the related working mechanisms. Finally, we present the challenges and prospects related to MXene synthesis, assembly, and application.

Structural color with polarization sensitivity has been widely studied due to its benefits for improving information storage and dynamic color display capacity. However, large amount and good concealment of information encoding are the major issues to be addressed. Here, we propose the elliptical Al/a-Si/Al (metal-insulator-metal, MIM) nanostructure arrays as the basic building blocks to realize polarization-sensitive subtractive structural colors for information encoding, and dynamic polarization-resolved displays. The experimentally realized structural color exhibits a wide color gamut covering the whole cyan, magenta, and yellow (CMY) color system, and presents a strong dependence on the incident polarization state due to its shape anisotropy. A new approach to improve the information encoding capacity is demonstrated using this structure combined with the polarization-independent nanostructures, increasing the concealment of information. Additionally, the polarization controllable dynamic display is engineered by the well-designed pixels with respect to different polarizations, generating the animation effect. These intrinsic properties and functionalities of the proposed structural color significantly extend its potential to the fields of information encoding, security encryption, and dynamic displays, not limited to color printing and filtering devices.