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Although the current overall economy in China has entered a new stage that features “slowdown, industrial upgrading and structural adjustment”, but the urban-rural dual economic structure of our economy and the long-standing complex regional differences still exist objectively. Our society and enterprises inevitably go into a transition period characterized with “changes”, even say “rapid changes”. How enterprises can promptly identify the “changes”, understand the “changes”, make the “changes”, and finally adapt to the “changes”, all these can directly affect the development of enterprises’ cumulative competitive advantage and determine their competition positions in the market. Therefore, to highlight the importance of Dynamic Capabilities and to study its contents and its working mechanism is of extraordinary importance for our enterprises both on practice and on theory. This Article explained the contents and measurement and other documental theories related to Dynamic Capabilities and further proved with questionnaire answers collected from key property developers in China, studied the contents and the working mechanism of Dynamic Capabilities, so as to provide a useful inspiration and reference. [ABSTRACT FROM AUTHOR]

Abstract: Hough transform neural network is adopted to detect the line pattern of direct wave and the hyperbolic pattern of reflection wave in a one-shot seismogram. We use time difference from point to hyperbola and line as the distance in the pattern detection of seismic direct and reflection waves. This distance calculation makes the parameter learning feasible. One set of parameters represents one pattern. Many sets of parameters represent many patterns. The neural network can calculate the distances from point to many patterns as total error. The parameter learning rule is derived by gradient descent method to minimize the total error. The network is applied to three kinds of data in the experiments. One is the line and hyperbolic pattern in the image data. The second is the simulated one-shot seismic data. And the last is the real one-shot seismic data. Experimental results show that lines and hyperbolas can be detected correctly in three kinds of data. The method can also tolerate certain level of noise data. The detection results in the one-shot seismogram can improve the seismic interpretation and further seismic data processing. [Copyright &y& Elsevier]

Shows the extensive computer results of the principal components analysis (PCA) using the neural network of generalized Hebbian algorithm (GHA). Description of the neural network of generalized Hebbian learning rule; Effect of adding one extra point along the direction of existing Eigenvector; Presentation of PCA in seismic ricker wavelet analyses.

A simple, green, cost- and energy-efficient route for converting phenolic components in bio-oil to hydrocarbons and methanol has been developed, with nearly 100% yields. In the heterogeneous catalysts, RANEY® Ni acts as the hydrogenation catalyst and Nafion/SiO2acts as the Brønsted solid acid for hydrolysis and dehydration. [ABSTRACT FROM AUTHOR]

The joint utilization of multi-source data is of great significance in geospatial observation applications, such as urban planning, disaster assessment, and military applications. However, this approach is confronted with challenges including inconsistent data structures, irrelevant physical properties, scarce training data, insufficient utilization of information and an imperfect feature fusion method. Therefore, this paper proposes a novel binary-tree Transformer network (BTRF-Net), which is used to fuse heterogeneous information and utilize complementarity among multi-source remote sensing data to enhance the joint classification performance of hyperspectral image (HSI) and light detection and ranging (LiDAR) data. Firstly, a hyperspectral network (HSI-Net) is employed to extract spectral and spatial features of hyperspectral images, while the elevation information of LiDAR data is extracted using the LiDAR network (LiDAR-Net). Secondly, a multi-source transformer complementor (MSTC) is designed that utilizes the complementarity and cooperation among multi-modal feature information in remote sensing images to better capture their correlation. The multi-head complementarity attention mechanism (MHCA) within this complementor can effectively capture global features and local texture information of images, hence achieving full feature fusion. Then, to fully obtain feature information of multi-source remote sensing images, this paper designs a complete binary tree structure, binary feature search tree (BFST), which fuses multi-modal features at different network levels to obtain multiple image features with stronger representation abilities, effectively enhancing the stability and robustness of the network. Finally, several groups of experiments are designed to compare and analyze the proposed BTRF-Net with traditional methods and several advanced deep learning networks using two datasets: Houston and Trento. The results show that the proposed network outperforms other state-of-the-art methods even with small training samples. [ABSTRACT FROM AUTHOR]

Abstract: Nanoparticle (NP) catalysis in liquid phase, which is usually called “soluble” NP catalysis, is an old topic but is now well advanced due to the great progress in nano-chemistry and nano-technology in green chemistry. After a short introduction of the history, this review describes the current status of NP catalysis in solvents and then discusses the main drawbacks hindering the particles from industrial practice. Efficiency, stability, sustainability, and recyclability (ESSR) criteria were suggested to evaluate NP catalytic systems. A state-of-the-art approach to satisfy ideal ESSR criteria is to produce cohesion over the individual contributions of metal center, stabilizer and solvent (MSS), i.e., a cohesive MSS approach. Based on reported examples, the roles that the metal core, the stabilizer and the solvent play in NP catalysis are discussed in detail. For clarity, a fairly complete list of NP catalytic systems in various green solvents reported in recent decade is provided. [Copyright &y& Elsevier]

The use of room temperature ionic liquids as either solvents or catalysts has been the subject of considerable recent attention because of the prospects for “green” catalysis. This paper presents a review of the potential applications of these unique liquid materials in industrial catalysis. [Copyright &y& Elsevier]

Rhodium–nickel bimetallic nanocrystals were fabricated with high activity in hydrogenation of olefins, nitroarenes and arenes at room temperature, indicating that bimetallic nanocrystals of noble and non-noble metals represent a novel kind of nanocatalyst. [ABSTRACT FROM AUTHOR]

Abstract: Poly-vinylpyrrolidone (PVP) stabilized nanoparticle (NP) catalysts are among the most active NP catalysts demonstrating excellent activities and stabilities in a wide and diverse range of reactions. One of the main limitations, that tend to prevent their use in industrial processes, is that they cannot be easily separated from reactions that are not amenable to biphasic separations, i.e. those involving hydrophilic reaction products. We describe a durable and recyclable Au NP catalyst system based on modified PVP that is thermo-sensitive, termed C1-PVP. C1-PVP stabilized Au NPs are similar in size, and exhibit similar properties, to Au NPs stabilized by PVP, but their additional thermo-sensitivity enables their facile separation from hydrophilic reaction products by mild heating, resulting in their precipitation. XRD, XPS, TEM, temperature dependant NMR, DLS and UV–vis analysis, as well as catalytic recycling and metal leaching tests were carried out to fully characterize the thermo-sensitive behavior of C1-PVP stabilized Au NPs. The C1-PVP stabilized Au NPs were systematically compared to Au NPs stabilized by PVP demonstrating the superiority of the new system and their potential green benefits. [Copyright &y& Elsevier]

Heteronuclear Au-Pd nanoparticles were prepared and immobilized in the functionalized ionic liquid [C2OHmim][NTf2]. The structural and electronic properties of the nanoparticles were characterized by a range of techniques and the surface of the nanoparticles was found to be enriched in Pd. Moreover, the extent of Pd enrichment is easily controlled by varying the ratio of Au and Pd salts used in the synthesis. The heteronuclear nanoparticles were found to be effective catalysts in dehalogenation reactions with no activity observed for the pure Au nanoparticles and only limited activity for the pure Pd nanoparticles. The activity of the heteronuclear nanoparticles may be attributed to charge transfer from Pd to Au and consequently to more efficient reductive elimination. [ABSTRACT FROM AUTHOR]

Abstract: Aqueous phase Fischer–Tropsch synthesis catalyzed by Ru nanoparticles was studied in a continuous flow reactor for the first time. A 60ml autoclave was used for catalyst screening and a 1000ml reactor was used to test the scale-up stability of the catalysts. Ru nanoparticles reduced by hydrogen in the presence of poly(N-vinyl-2-pyrrolidone) (PVP) showed the highest activity compared with those of the particles reduced by other reductants. PVP/Ru molar ratio and reaction temperature were two key factors responsible for the stability and activity of the catalysts. With a PVP/Ru molar ratio of 40, Ru nanoparticles kept an almost steady space-time yield (STY) of C5+ hydrocarbons 0.51g-C5+ g-cat−1 h−1 throughout 240h running at 150°C. The size of Ru nanoparticles grew very slightly from 2.0nm before the reaction to 2.2nm after the reaction. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and Gel Permeation Chromatography were used to reveal the structural information of the catalysts before and after reaction, and the characterization results were correlated with the catalytic performances. [Copyright &y& Elsevier]

Abstract: A new method was developed to fabricate ultrafine cobalt nanoparticles with an average diameter of 2.8nm from large precursory cobalt nanoparticles (around 20nm). The obtained ultrafine nanoparticles have a narrow size distribution and a much higher Co/B ratio than that of precursory cobalt nanoparticles (almost 100 times higher). The 2.8nm cobalt nanoparticles were used to catalyze hydroformylation of 1-hexene and syngas (CO: H2 =1) at 100°C and 2.4MPa, resulting in an average TOF (turnover frequency) of 130h−1. Through the mercury poisoning experiments, it was observed that the presence of Hg (0) can effectively suppress the catalytic activity of the 2.8nm Co nanoparticle catalyst system, demonstrating that a heterogeneous catalysis mechanism was followed in the ultrafine catalyst system. [ABSTRACT FROM AUTHOR]

Abstract: Reaction of the zwitterionic imidazolium salt [(CH2COOH)(CH2COO)im] with K2CO3 or BaO in the presence of 18-crown-6 affords the salts [(CH2COO)2im][K(18-crown-6)] and [(CH2COO)2im]2[Ba(18-crown-6)], respectively. Recrystallisation of these crown complexes from the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide, [emim][Tf2N], at a water interface, results in the formation of new salts in which the original anion is replaced by Tf2N−. Single crystal X-ray diffraction has been performed on two of the salts. Notably, the potassium structure containing 18-crown-6 and Tf2N− forms a linear chain coordination polymer that can be regarded as metal organic frameworks (MOFs). Moreover, this study provides insights into the separation of group I and II metal ions using crown ethers in combination with ionic liquids. [Copyright &y& Elsevier]

Abstract: A biphasic approach to the dehydroaromatization of bioderived limonene into water-insoluble p-cymene using soluble Pd nanoparticle catalysts in an aqueous phase (⩾150 °C, 2 bar H2) was successfully achieved with a conversion of 93% and a selectivity of 82%. The Pd nanoparticles, operating under forcing conditions (180 °C, 2 bar H2), can be recycled at least four times without noticeable degradation. The effects of temperature, pressure, reaction time, pH, catalyst concentration, metal type, the type and amount of polymer stabilizer, and the preparation method were systematically investigated to optimize the process and provide insight into the mechanisms involved. [Copyright &y& Elsevier]

Abstract: Rhodium nanoparticles stabilized by the ionic-liquid-like copolymer poly[(N-vinyl-2-pyrrolidone)-co-(1-vinyl-3-butylimidazolium chloride)] were used to catalyze the hydrogenation of benzene and other arenes in ILs. The nanoparticle catalysts can endure forcing conditions (75 °C, 40 bar H2), resulting in high reaction rates and high conversions compared with other nanoparticles that operate in ILs. The hydrogenation of benzene attained record total turnovers of 20,000, and the products were easily separated without being contaminated by the catalysts. Other substrates, including alkyl-substituted arenes, phenol, 4-n-propylphenol, 4-methoxylphenol, and phenyl-methanol, were studied and in most cases were found to afford partially hydrogenated products in addition to cyclohexanes. In-depth investigations on reaction optimization, including characterization of copolymers, transmission electron microscopy, and an infrared spectroscopic study of nanocatalysts, were also undertaken. [Copyright &y& Elsevier]

Abstract: An ionic-liquid-like copolymer was used to stabilize the platinum nanoclusters in ionic liquids. Catalytic performance was tested by the selective hydrogenation of o-chloronitrobenzene. Platinum catalysts Pt-I (5.1 nm) and Pt-II (1.7 nm) both exhibited excellent activity and selectivity for the reaction and were recycled with the activity and selectivity preserved. An unprecedented total turnover number () was obtained on the Pt-II catalyst. Infrared spectroscopy, transmission electron microscopy, X-ray diffraction characterizations, and density functional theory calculations were used to study the catalysts. [Copyright &y& Elsevier]

Abstract: The electrochemistry of dopamine (DA) was studied by cyclic voltammetry at a glassy carbon electrode modified by a gel containing multi-walled carbon nanotubes (MWNTs) and room-temperature ionic liquid of 1-octyl-3-methylimidazolium hexafluorophosphate (OMIMPF6). The thickness of gel on the surface of the electrode has to be controlled carefully because the charging currents increase with the modified layer being thicker. The anodic peaks of DA, ascorbic acid (AA) and uric acid (UA) in their mixture can be well separated since the peak potential of AA is shifted to more negative values, while that of UA is shifted to more positive values due to the modified electrode. At pH 7.08 the three peaks are separated ca. 0.20 and 0.15V, respectively; hence DA can be determined in the presence of UA and more than 100 times excess of AA. Under optimum conditions linear calibration graphs were obtained over the DA concentration range 1.0×10−6 to 1.0×10−4 M. The detection limit of the current technique was found to be 1.0×10−7 M based on the signal-to-noise ratio of 3. The modified electrode has been successfully applied for the assay of DA in human blood serum. This work provides a simple and easy approach to selectively detect dopamine in the presence of ascorbic acid and uric acid. [Copyright &y& Elsevier]

The Fe nanoparticles dispersed in polyethylene glycol (PEG) can catalyze Fischer–Tropsch (F-T) synthesis at mild conditions (150 °C, 2.0 MPa H2, 1.0 MPa CO) with an activity as high as 1.5 molCOmolFe−1h−1. The F-T products, hydrocarbons, are insoluble in the green solvent PEG, and could be easily separated from the reaction mixture. [ABSTRACT FROM AUTHOR]

Systematic fabrication of nanoparticle stabilizers can substantially modify the properties of prepared nanoparticles; here the synthesis of solubility adjustable nanoparticles is achieved by employing a family of polarity modulated stabilizers. [ABSTRACT FROM AUTHOR]

Bimetallic Au–Pd nanoparticles were prepared in the functionalized ionic liquid [C2OHmim][NTf2] by the thermal decomposition of Pd(OAc)2 and Au(OAc)3. The Au atoms are mostly located in the NP core, leaving the Pd atoms ENriched at the surface. Moreover, the Pd atoms are electropositive, which leads to high activity in catalytic dehalogENation reactions. The activity of the heteronuclear nanoparticles may be attributed to charge transfer from Pd to Au and consequENtly to more efficiENt reductive elimination. For more details, see the Full Paper by N. Yan et   al. on page   1227   ff. [ABSTRACT FROM AUTHOR]