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The very useful organic solvent 2-octanol is widely employed in the industry, and the direct hydration of olefins is an important method for its production. However, a slow transfer rate during a reaction due to the poor mutual solubility of the reactants is a problem; a cosolvent can be used to solve it. In this study, the feasibility of using the direct hydration of 1-octene via a catalytic distillation process using 1,4-dioxane as a cosolvent was investigated. First, the COSMOtherm program was used to identify and screen many typical cosolvents. Subsequently, the kinetics of the direct hydration reaction of 1-octene using 1,4-dioxane as a cosolvent and an HZSM-5 molecular sieve as the catalyst were determined experimentally. Finally, kinetic and thermodynamic models were utilized to create non-reactive and reactive residual curve maps to assess the feasibility of proceeding with the reaction. Applying a suitable Damköhler number (Da) value and the residual curve changes demonstrated that proceeding with the process was reasonable and feasible. For 0 < Da < 0.03, the reaction kinetics drove the process and 2-octanol was produced via a reaction distillation column procedure. Lastly, two conceptual design processes for the synthesis process of 2-octanol catalytic distillation were proposed and the related analysis carried out.

It is a key issue for the Chinese government to improve eco-efficiency and realize green development. As a spatial organization mode of industrial labor division, industrial agglomeration has a complex impact on eco-efficiency. However, it is still debatable which industrial agglomeration modes have a positive impact on eco-efficiency. This paper employs a panel threshold model, enterprise micro-level data, and relevant economic environment data from 283 cities in China from 2004 to 2012. It tests the nonlinear effects of specialized, related diversified, and unrelated diversified agglomeration on industrial eco-efficiency. The results show that the impact of specialized and related diversified agglomeration on industrial eco-efficiency is first inhibited and then promoted. The unrelated diversified agglomeration has a significantly negative impact on industrial eco-efficiency, but the negative impact weakens when agglomeration reaches a certain level. Furthermore, the impact of the three agglomeration modes on industrial eco-efficiency depends on city size. The impact of specialized agglomeration on industrial eco-efficiency is insignificant in small- and some medium-sized cities, but it has a significant inhibitory effect on industrial eco-efficiency when the city surpasses medium size. The role of related diversified agglomeration in promoting industrial eco-efficiency is further enhanced with the growth of city size. The impact of unrelated diversified agglomeration on industrial eco-efficiency gradually changes from negative to positive, but it plays a promoting role only when the city reaches the scale of super-large and mega-cities. Finally, this paper suggests that policymakers should formulate differentiated agglomeration policies according to changes in industrial agglomeration level or city size to improve industrial eco-efficiency.

In recent years, there has been an increasing interest in applying inverse data envelopment analysis (DEA) to a wide range of disciplines, and most applications have adopted radial-based inverse DEA models. However, results given by existing radial based inverse DEA models can be unreliable as they neglect slacks while evaluating decision-making units&rsquo, (DMUs) overall efficiency level, whereas classic radial DEA models measure the efficiency level through not only radial efficiency index but also slacks. This paper points out these disadvantages with a counterexample, where current inverse DEA models give results that outputs shall increase when inputs decrease. We show that these unreasonable results are the consequence of existing inverse DEA models&rsquo, failure in preserving DMU&rsquo, s efficiency level. To rectify this problem, we propose a revised model for the situation where the investigated DMU has no slacks. Compared to existing radial inverse DEA models, our revised model can preserve radial efficiency index as well as eliminating all slacks, thus fulfilling the requirement of efficiency level invariant. Numerical examples are provided to illustrate the validity and limitations of the revised model.

Gentrification, as a term introduced into China 20 years ago, has now become a topical word in scholarly discussion. This paper for the first time used the software of multiple pieces to analyze literature on gentrification between 1996 and 2017 in China based on bibliometrics, aiming to get the overview of the study, identify and expound the research themes, and analyze their evolution. It showed that the study on gentrification had entered into an exploratory stage with fluctuation from the early germination stage; gentrification research mainly concentrated on two disciplines, namely Geography and Urban and Rural Planning; the top 10 influential authors were identified and collaborative research teams leading the gentrification research had initially been formed. The themes of gentrification research in China were decided by visual analysis method, including urban renewal and dynamic mechanism of gentrification, evaluation and response to the effects of gentrification, new types of gentrification, and historical and cultural heritage conservation and creative industry, on which deeper content and information were described in detail. In terms of research themes evolution analysis, the results showed that the gentrification research in China had experienced the shift from initial concept and literature introduction to current empirical research and theory construction. There are significant signs showing the future trends of gentrification will move to the construction of a theoretical system of gentrification with Chinese characteristics, gentrification consequences evaluation and urban policies, new types of gentrification, gentrification driven by cultural consumption and authenticity protection of gentrification-stricken historical and cultural heritages, application of new technology to gentrification research, and relationship between shantytown renovation and gentrification in China. As to this paper, as far as the authors know, it is the first comprehensive systematic summary within this field based on bibliometric analysis.

A knotty issue concerning the poor mechanical properties exists in the porogen leaching approach to porous scaffolds, despite its advantage in tuning pore structure. To address this hurdle, solid state extrusion (SSE) combined with porogen leaching was utilized to engineer porous scaffolds of poly(lactic acid) (PLA). Advances introduced by poly(ethylene glycol) (PEG) caused the PLA ductile to be processed and, on the other hand, enabled the formation of interconnected pores. Thus, a well-interconnected porous architecture with high connectivity exceeding 97% and elevated porosity over 60% was obtained in the as-prepared PLA scaffolds with the composition of NaCl higher than 75.00 wt % and PEG beyond 1.25 wt %. More strikingly, the pore walls of macropores encompassed countless micropores and rough surface topography, in favor of transporting nutrients and metabolites as well as cell attachment. The prominent compressive modulus of the PLA scaffolds was in the range of 85.7⁻207.4 MPa, matching the normal modulus of human trabecular bone (50⁻250 MPa). By means of alkaline modification to improve hydrophilicity, biocompatible porous PLA scaffolds exhibited good cell attachment. These results suggest that the SSE/porogen leaching approach provides an eligible clue for fabricating porous scaffolds with high mechanical performance for use as artificial extracellular matrices.