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951.
952.
Have Chinese universities, after enormous investment over the past decade, embraced the university’s third mission—contributing to industrial and technological progress? The literature has not sufficiently addressed this question. This study intends to advance understanding of this issue by empirically addressing this question from a business perspective in a bold and unconventional way. Unlike prior studies that simply used contingent and institutional factors to describe the link between Chinese universities and industrial firms by measuring such aspects as patent licensing, co-patenting, and co-authoring, our work goes further and applies longitudinal analysis to examine the ways firms access university-level knowledge and the impact of such knowledge on firm innovation outputs. We propose that if Chinese universities embraced their third mission, then we would observe a positive effect of university–industry collaborations on firms’ subsequent innovation outputs. Empirical results based on a sample of the top 100 Chinese electronic firms in terms of output value support our hypothesis. Specifically, university patent licensing and co-patenting between universities and firms was found to positively affect firm innovation outputs. Moreover, we found that geographical distance and collaboration dominance moderate the co-patenting–innovation output relationship. 相似文献
953.
The toughness of conventional injection-molded isotactic polypropylene bars has been investigated with respect to the notch location and β-nucleating agent. Superior toughness is achieved in the β-nucleated bars with notches near the gate, but is absent in the near-gate bars without β-nucleating agent or in the β-nucleated ones far from the gate. With detailed structural analysis across the sample thickness, it is indicated that in these tough bars, extensive flow close to the surface suppresses the formation of β-form to a large extent but favors the generation of oriented α-form, whereas toward inner region, an opposite tendency is presented with the decay of flow strength and the activation of β-nucleating agent. Allowing that this peculiar hierarchical structure is absent in other two kinds of bars, it is deduced that the cooperative effect of molecular orientation of α-form in the skin layer and rich β-form in the inner region is responsible for the significant toughness enhancement in the β-nucleated bars near the gate. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
954.
955.
Various processes can occur when paints are in contact with moisture, such as ingress of water and aggressive ions into the coating. As a consequence, the microstructure and properties of the paints can be affected. The present study combines electrochemical impedance spectroscopy (EIS) and in situ atomic force microscopy (AFM) to investigate the barrier property of waterborne and solventborne coatings on mild steel, paying particular attention to the occurrences in the first 24 h after contact between the coating surface and electrolyte. The sequential in situ AFM images revealed that changes on the order of hundreds of nanometres at the coating surface have occurred shortly after the exposure to the electrolytes. EIS observations for the clear waterborne alkyd coating revealed a rise in the |Z|0.015Hz and a decrease in the coating capacitance after a few hours of exposure. Evidences that water uptake caused swelling of the coating and promoted the closure/blockage of pores were given by means of in situ AFM. The solventborne alkyd emulsion has demonstrated lower reactivity to the presence of the electrolyte and a correlation between the coating resistance and defects/pores evolution is suggested. 相似文献
956.
Wenzhu Liao Ying Wang Ershun Pan 《The International Journal of Advanced Manufacturing Technology》2012,63(1-4):51-63
As an increasing number of manufacturers are beginning to realize the importance of maintaining throughput, many maintenance models have been developed to enable machines to achieve near-zero downtime. However, previous maintenance models usually ignore machine’s deterioration process. Therefore, this paper develops a novel data-driven machinery prognostic approach for machine performance assessment and prediction. With this prognostic information, a predictive maintenance model is proposed for a repairable deteriorating machine. As machine performance can be assessed, once it reaches the maintenance threshold, a maintenance operation is performed to restore the machine. Moreover, an operational cost is introduced to meet real manufacturing process. In this predictive maintenance model, the optimal maintenance threshold and maintenance cycle number are obtained with the aim to minimize the long-term average cost. Finally, a case study is presented. The computational results show the efficiency of this proposed predictive maintenance model. 相似文献
957.
Metallurgical and Materials Transactions A - Two microscale numerical models are developed in this work using a moving-mesh approach to investigate the growth process of pitting in different iron... 相似文献
958.
Feifei Li Haoqiang Ai Changmin Shi Kin Ho Lo Hui Pan 《International Journal of Hydrogen Energy》2021,46(24):12886-12896
Electrochemical CO2 reduction reaction (CO2RR) is an efficient way in the utilization of CO2. In this work, single transition-metal (TM) atom (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn) anchored on two-dimensional (2D) Ti2CN2 are designed for CO2RR using density-functional-theory (DFT) calculation. We show that Ti2CN2 serves as an excellent substrate to support single atom catalysts (SACs), compared to Ti2CO2 and Ti2CF2. We find that the Sc, Ti and V supported on Ti2CN2 show high catalytic activities to produce CO with a low overpotential of 0.37, 0.27, and 0.23 eV, respectively. Differently, the Mn and Fe on Ti2CN2 are catalytically active for the production of HCOOH with a low overpotential of 0.32 and 0.43 eV, respectively. We further show that the negatively charged TM-Ti2CN2 can capture and activate CO2 more effectively, and the catalytic activity and selectivity can be significantly tuned by injecting extra electrons. 相似文献
959.
Lu Yang Dr. Mingwei Liang Dr. Cheng Cui Xiaowei Li Long Li Xiaoshu Pan Hoda Safari Yazd Dr. Min Hong Prof. Jianrong Lu Prof. Y. Charles Cao Prof. Weihong Tan 《Chembiochem : a European journal of chemical biology》2021,22(4):754-759
Functional nucleic acids (FNAs) are garnering tremendous interest owing to their high modularity and unique bioactivity. Three-dimensional FNAs have been developed to overcome the issues of nuclease degradation and limited cell uptake. We have developed a new facile approach to the synthesis of multiple three-dimensional FNA nanostructures by harnessing photo-polymerization-induced self-assembly. Sgc8 aptamer and CpG oligonucleotide were modified as macro chain-transfer reagents to mediate in situ polymerization and self-assembly. Diverse structures, including micelles, rods, and short worms, afford these two FNAs afford these two FNAs with higher nuclease resistance in serum serum, greater cellular uptake efficiency, and increased bioactivity. 相似文献
960.