Peng Xia, Kunjie Li, Fangui Zeng, Xiong Xiao, Jianliang Zhang, Jianhua Xiang and Beilei Sun
Pyrolysis for coal gas generation changes the composition, pore structure, permeability and adsorption capacity of coal. This work aims to discuss the utilization of coal…
Abstract
Purpose
Pyrolysis for coal gas generation changes the composition, pore structure, permeability and adsorption capacity of coal. This work aims to discuss the utilization of coal pyrolysis on enhancing coalbed methane (CBM) production in the Gujiao area, Shanxi province, China.
Design/methodology/approach
This research was conducted mainly by the methods of thermogravimetry mass spectrometry (TG-MS) analysis, liquid nitrogen adsorption experiment and methane isothermal adsorption measurement.
Findings
The results can be concluded as that 400-700°C is the main temperature range for generating CH4. Pore volume and specific surface area increase with increasing temperature; however, the proportion of micro pore, transition pore and macro pore has no difference. The optimum temperature for enhancing CBM production should be letter than 600°C because the sedimentation of tar and other products will occupy some pores and fissures after 600°C.
Originality/value
Here in, to accurately recognize the suitable maximum temperature for heating development, a method enhancing CBM production, TG-MS, was adopted to analyze the products and the weight loss of coals with different ranks in the Gujiao area at temperature of 30-1,100°C. And then the pore structure, porosity, permeability, methane adsorption capacity and thermal maturity of coals during pyrolysis were investigated with increased temperature from 30°C to 750°C. On these bases, the favorable condition for enhancing CBM production and the thermal evolution of coal were recognized.
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Yusi Jiang, Yapu Zhao and Beilei Dang
This study explores the influence of partner innovation in board interlock networks on a firm's innovation tendency.
Abstract
Purpose
This study explores the influence of partner innovation in board interlock networks on a firm's innovation tendency.
Design/methodology/approach
This study collects a sample of publicly listed Chinese firms from 2008 to 2017 and uses fixed-effects ordinary least squares regressions to analyze the data.
Findings
This study shows that interlocking partners with different innovation levels than that of the focal firm affect its innovation tendency in distinct ways. For more innovative partners, the innovation level has a U-shaped effect on the focal firm's innovation tendency. In the case of less innovative partners, the innovation level facilitates the focal firm's innovation tendency.
Originality/value
Going beyond previous research that emphasized the role of interorganizational networks in facilitating firm innovation through a unitary learning effect, this study differentiates network partners into two categories based on their relative level of innovation compared with the focal firm and takes the hitchhiking effect into account to highlight potential obstacles in the learning process depending on the innovation conditions of partners. The study advances the literature on organizational learning, social networks and innovation.
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Haifeng Wang, Yapu Zhao, Beilei Dang, Pengfei Han and Xin Shi
The impact of network centrality on innovation performance is inconclusive. The purpose of this paper is to examine how formal and informal institutions affect the influence of…
Abstract
Purpose
The impact of network centrality on innovation performance is inconclusive. The purpose of this paper is to examine how formal and informal institutions affect the influence of network centrality on firms’ innovation performance in emerging economies by integrating social network theory and institutional theory.
Design/methodology/approach
Multisource and lagged data from 234 technology-based entrepreneurial firms listed on the Chinese Growth Enterprise Market were leveraged to test a proposed research model.
Findings
Results suggest that formal institutions (marketization) positively moderate the relationship between network centrality and innovation performance, whereas informal institutions (social cohesion) negatively moderate this relationship. Moreover, formal and informal institutions have a strong joint impact on such relationship, that is, the effect of network centrality on innovation performance is most positive when marketization is high and social cohesion is low.
Originality/value
This empirical research provides new insights into whether and how firms can grasp the innovation benefits of network centrality by exploring institutional contingencies. It further sheds on light the scope of the network centrality–innovation issue by extending its research context to Chinese entrepreneurial firms.
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Shanhua Qian, Longfei Gong, Wei Wang, Zifeng Ni and Haidong Ren
This study aims to reduce the harm of industrial lubricants to consumers. Composite aluminum-based grease (CAG) was prepared, and medical-grade montmorillonite (M-MMT) was used to…
Abstract
Purpose
This study aims to reduce the harm of industrial lubricants to consumers. Composite aluminum-based grease (CAG) was prepared, and medical-grade montmorillonite (M-MMT) was used to improve the antiwear performance of the prepared grease.
Design/methodology/approach
The influence of the additive (M-MMT) on the tribological performance is mainly investigated using a ball-disc wear tester, and the wear scar surface about the disc was characterized by white light interferometer and electrochemical workstation. Moreover, the cell viability test was used to evaluate the safety of the grease.
Findings
The results indicated that for the grease containing 1.5% M-MMT, the average coefficient of friction was reduced by about 46% compared with the CAG, the wear volume of the disc reduced by about 74%. Moreover, CAG and 1.5% M-MMT-containing CAG were proved safety by means of the cell viability test.
Originality/value
The integral properties of CAG can be improved with the medical-grade materials as the additives, while ensuring the safety.
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Wei Gong, Xiao-Yan Wang, Xiao Wang, Wen Wang and Yan-Li Yang
To ensure the reliable and safe operation of elevated-temperature pipes and equipment in the long term, it is essential to thoroughly assess the creep rupture life. Nevertheless…
Abstract
Purpose
To ensure the reliable and safe operation of elevated-temperature pipes and equipment in the long term, it is essential to thoroughly assess the creep rupture life. Nevertheless, there is currently no design code that specifies a creep rupture life evaluation method for non-nuclear elevated-temperature equipment. The paper aims to discuss this issue.
Design/methodology/approach
An analysis was conducted to compare the differences and conservativeness in calculating creep strain using three major codes (ASME-CC-2843, API-579 and BS-7910) based on the results of the 316H creep constitutive model and creep strain prediction. In addition, the creep resistances of 316H, 304H and 347H were compared. Subsequently, the ANSYS Usercreep subroutine was developed to compare the discrepancies between different codes under multiaxial stress conditions using numerical simulations.
Findings
BS-7910 employs the Norton creep model with calculation parameters for the average creep strain rate, which is not applicable for the engineering design stage. ASME-CC2843 code primarily focuses on the primary and secondary creep stages, making it more suitable for non-nuclear pipeline and equipment design. For 316H, the creep strain curves predicted by ASME-CC2843 and API-579 typically intersect at a specific point. By combining the creep strain predicted by ASME-CC2843 and API-579, 347H exhibits superior predicted creep resistance compared to 316H, whereas 316H exhibited better predicted creep resistance than 304H.
Originality/value
This study provides a guide for future evaluation methods and material choices for non-nuclear equipment and pipelines operating at elevated temperatures.