Xuzhong Su, Xinjin Liu and Xiaoyan Liu
Pneumatic compact spinning is the most widely used compact spinning method at present, in which the negative pressure airflow is used to condense the fiber in order to decrease…
Abstract
Purpose
Pneumatic compact spinning is the most widely used compact spinning method at present, in which the negative pressure airflow is used to condense the fiber in order to decrease the spinning triangle and improve the yarn qualities. Therefore, the research on flow field in the condensing zone is always the emphasis for pneumatic compact spinning. The paper aims to discuss these issues.
Design/methodology/approach
By using finite element method (FEM), the flow field in two kinds of pneumatic compact spinning was studied. Taking three kinds of cotton yarns as examples, with the help of high-speed camera system OLYMPUS i-SPEED3, the motion trajectory of fiber strand in the condensing zone was obtained. Three-dimensional physical models of the condensing zone of the two compact spinning systems were obtained according to the measured parameters of practical spinning systems.
Findings
It is shown that on the both left edge of B1 line and right edge of B2 line, the airflow inflows to the center line of suction slot, and the condensed effects are produced, correspondingly. In the condensing zone, there are three condensing processes acting on the fiber strand, including the rapid condensing effects in the front condensing zone, the adequately condensing effects in the middle condensing zone, and stable output effects in the back condensing zone.
Originality/value
By using FEM, numerical simulations of three-dimensional flow field in condensing zone for two kinds of pneumatic compact spinning with lattice apron were presented, and corresponding spun yarn qualities were analyzed.
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Xiaoyan Liu and Kun Yu
The purpose of the paper is to understand the detrimental effects of vocational delay of gratification (VDG) based on the ego-depletion perspective and to explore the specific…
Abstract
Purpose
The purpose of the paper is to understand the detrimental effects of vocational delay of gratification (VDG) based on the ego-depletion perspective and to explore the specific mechanism in this dynamic process.
Design/methodology/approach
The study used experience sampling to survey 89 employees at 3 time points within each day over 10 days and built a 4-stage sequential mediation model.
Findings
Results revealed that, at the daily level, afternoon VDG had a positive effect on end-of-day work–family conflict through afternoon ego depletion. The work–family conflict continued the state of ego depletion to the next morning and led to poor job dedication the next morning.
Research limitations/implications
The findings suggest organizations and employees should consider not only the benefits of delay of gratification (DG) but the costs as well.
Originality/value
The current study is the first to investigate a dark side of VDG and to explore its underlying mechanism.
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Ruijie Zhang, Xiaoyan Liu, Zhaopeng Wang and Fei Gao
The purpose of this study is to research the effects of interrupted aging on the corrosion behavior of Al–Cu–Mg–Ag heat-resistant alloy by means of intergranular corrosion (IGC…
Abstract
Purpose
The purpose of this study is to research the effects of interrupted aging on the corrosion behavior of Al–Cu–Mg–Ag heat-resistant alloy by means of intergranular corrosion (IGC) testing, potentiodynamic polarization combined with optical microscopy and transmission electron microscopy.
Design/methodology/approach
The results show that the IGC began on the grain boundaries and continued along the grain boundary. The corrosion resistance property of Al–Cu–Mg–Ag alloy was enhanced by interrupted aging. The precipitations of the interrupted aged sample both in the grains and on the grain boundaries were fine, and the chain-like phases on the grain boundary were distributed nearly continuously.
Findings
The corrosion resistance of Al–Cu–Mg series Al alloy with equilibrium phase (Al2Cu) is notably determined by precipitation-free zone (PFZ) as the self-corrosion potentials of (Al2Cu), PFZ and the matrix satisfied the relation EPFZ < Eθ<EMatrix.
Originality/value
The connections of the PFZ on both sides of the grain boundary decreased the corrosion resistance of Al–Cu–Mg–Ag alloy treated by the single aging.
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Xiaoyan Liu, Weidong Yu, Yukun Tao, Xiaoling Wang and Ying Li
High performance aramid fibers display high tenacity, modulus and temperature resistance under various end-use applications. Since no scientific research papers on the subject of…
Abstract
High performance aramid fibers display high tenacity, modulus and temperature resistance under various end-use applications. Since no scientific research papers on the subject of Kermel fibers are found, the thermal degradation properties of Kermel and poly-p-phenylenebenzobisoxazole (PBO) fibres are therefore compared in this paper. When heated to temperatures of 100°C, 200 °C, 300°C, and 400°C for 1.5 hours, the tenacity and extension-to-break properties of PBO and Kermel fibres both decrease with temperature, but the modulus first increases, and then decreases until 300°C. By using a scanning electron microscope (SEM) to observe the effect of heat treatment on these fibres, the morphologies of PBO and Kermel fibres exhibit fractures when they are ruptured and fibrils are found in their cores.
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PBO and p-aramids fibers were compared on thermal degradation in TG and DTG experiments, and PBO fiber showed the highest degradation temperature in both air and nitrogen…
Abstract
PBO and p-aramids fibers were compared on thermal degradation in TG and DTG experiments, and PBO fiber showed the highest degradation temperature in both air and nitrogen atmosphere. Annealed under high temperature of 100°C, 200°C, 300°C and 400°C for 1.5 hours, the tenacity of these samples all decreased with the temperature, while PBO fiber showed the best tensile retention property. Whereas using the xenon arc light to simulate sunlight irradiated on the PBO and Kevlar samples for different time respectively, PBO showed the worst tensile retention property. In contrast, the p-aramid fibers showed their relatively good mechanical stability when exposed to the simulated sunlight. Therefore, the application of PBO fibers should be careful in the state of sunlight irradiation although PBO has the highest original mechanical and thermal property.
Ramji Nagariya, Divesh Kumar and Ishwar Kumar
The purpose of this study is to carry out the systematic literature review, bibliometric analysis and content analysis of extant literature of service supply chain (SSC).
Abstract
Purpose
The purpose of this study is to carry out the systematic literature review, bibliometric analysis and content analysis of extant literature of service supply chain (SSC).
Design/methodology/approach
Systematic literature review (SLR) technique was used for identifying the research papers. In the first step after reading titles, abstracts and keywords and, full-length articles wherever required, papers not related to SSC were removed. In second steps papers were read more critically and papers not related to SSC were removed. Finally on 502 papers bibliometric and content analysis was further carried out. Content analysis was based on the clusters formed by bibliographic coupling. Further, content analysis of the recent articles revealed the current research trends and research gaps.
Findings
This paper identified the six existing research diversifications in SSC as (1) logistics SSC, (2) model, framework and conceptual papers, (3) third-party logistics service providers, (4) articles from various perspective, (5) measurement of quality and performance on services and (6) impact of adoption of technology, cooperation and branding on logistics service providers. Further, six future research directions are also provided.
Practical implications
This research provides a clear view of the progression of publication, research diversification, research themes of six identified clusters, sub-themes of clusters and content analysis of each cluster. Content analysis of recent articles reveals the current research trend and future research directions.
Originality/value
This is a first of its kind of study which presents the diversification of research areas within SSC, bibliometric analysis, content analysis and provides actionable future research direction.
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Chuanmin Mi, Lin Xiao, Sifeng Liu and Xiaoyan Ruan
With respect to the multiple-attribute decision-making problem with subjective preference for a certain attribute whose weight-value range have been given over other attributes…
Abstract
Purpose
With respect to the multiple-attribute decision-making problem with subjective preference for a certain attribute whose weight-value range have been given over other attributes whose weight values are unknown, a method based on the mean value of the grey number is proposed to analyse the decision-making problem. This method is used to choose a supply-chain partner under the condition that the decision makers have a preference for a certain attribute of various alternatives. The paper aims to discuss these issues.
Design/methodology/approach
First, the middle value of the preferred attribute’s weight-value range is supposed to be its weight value according to the content of the mean value of the grey number. Second, to reflect the decision maker’s subjective preference information, an improved optimisation model that requests the minimum deviation between the actual and expected numerical value of each attribute is constructed to assess the attributes’ weights. Third, the correlated degree and the correlation matrix, which are determined by the weight values of all attributes, are used to rank all the alternatives.
Findings
This paper provides a method for making a decision when decision makers have a preference for a certain attribute from an array of various alternatives, and the range of the certain attribute’s weight value is given but the weight value of the other attributes is unknown. When applied to supply-chain partner selection, this method proves feasible and effective.
Practical implications
This method is feasible and effective when applied to supply-chain partner selection, and can be applied to other kinds of decision-making problems. This means it has significant theoretical importance and extensive practical value.
Originality/value
Based on the mean value of the grey number, an optimisation model is built to determine the importance degree of each attribute, then the correlated degree of each alternative is combined to rank all the alternatives. This method can suit the decision makers’ subjective preference for a certain attribute well.
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Pan Liu, Xiaoyan Cui, Ziran Zhang, Wenwen Zhou and Yue Long
The purpose of this paper is to solve new pricing issues faced by low-carbon companies in the Yellow River Basin, which is caused by the change of key pricing factors in the mixed…
Abstract
Purpose
The purpose of this paper is to solve new pricing issues faced by low-carbon companies in the Yellow River Basin, which is caused by the change of key pricing factors in the mixed appliance background of Big Data and blockchain, such as product quality and carbon-emission reduction CER level (hereafter, CER level).
Design/methodology/approach
We choose a low-carbon supply chain with a low-carbon manufacturer and a retailer as our research object. Then, we propose that using the ineffective effect of the CER level and the quality and safety level to reflect the relationships among the CER level, the quality and safety level and the market demand is more suitable in the new environment. Based on these, we revise the demand equation. Afterwards, by using Stackelberg game, four cost-sharing situations and their pricing rules are analyzed.
Findings
Results indicated that in the four cost-sharing situations, the change trends and the magnitudes of the best retail prices were not affected by the changes of the inputs of the demand information and the traceability services costs (hereafter, DITS costs), the proportion about retailer's DITS costs undertaken by the manufacturer, the ineffective effect coefficient of the CER level and the quality and safety level and the cost optimization coefficient. However, the cost-sharing situations could affect the change magnitudes of the best revenues.
Originality/value
This paper has two main contributions. First, this paper proposes a demand function that is more suitable for the mixed appliance background of Big Data and blockchain. Secondly, this paper improves the cost-sharing model and finds that demand information sharing and traceability service sharing have different impacts on key pricing factors of low-carbon product. In addition, this research provides a theoretical reference for low-carbon supply chain members to formulate pricing strategies in the new background.
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Jun Zhang, Meng Wang, Pu Liu, Xiaoyan Zhang, Ting Huo, Zhengcan Chen, Chunli Liu, Boyuan Zhang, Shengyuan Zhao and Zhenbin Chen
In this study, a novel glutathione (GSH) surface molecular imprinting polymer (SMIP) was successfully prepared by using macroporous adsorption resins (MAR) as substrate, which…
Abstract
Purpose
In this study, a novel glutathione (GSH) surface molecular imprinting polymer (SMIP) was successfully prepared by using macroporous adsorption resins (MAR) as substrate, which could separate and purify GSH efficiently.
Design/methodology/approach
SMIP was synthesized by chloromethylated modified MAR (LX1180-Cl) as the substrate, N, N’-methylenebisacrylamide (NMBA) as a crosslinker, GSH as a template, acrylamide (AM) and N-vinylpyrrolidone (NVP) as functional monomers. The morphology and structure of the polymer were characterized by scanning electron microscope and Fourier transforms infrared spectroscopy.
Findings
The maximum adsorption capacity toward GSH was 39.0 mg/g and the separation decree had relation to L-cysteine (L-cys) was 4.2. The optimal operation conditions were studied in detail and the got as follows: the molar ratios of NMBA, AM, GSH and NVP, were 7.0, 0.8 and 0.5. The optimal time and temperature were 14 h and 40°C, respectively. The Langmuir and pseudo-first-order model were fitting these adsorption characteristics well.
Practical implications
GSH has a diversity of medicinal and bioactive functions, so the purpose of this study representing a method in separate and purify technology of GSH, which provided a way for the development of medicine.
Originality/value
This contribution provided a novel way to separate GSH from L-cys. Under the optimal conditions, the maximum adsorption capacity toward GSH was 39.0 mg/g and the separation decree had relation to L-cys was 4.2.
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Peng Yao, Xiaoyan Li, Fengyang Jin and Yang Li
This paper aims to analyze the morphology transformation on the Cu3Sn grains during the formation of full Cu3Sn solder joints in electronic packaging.
Abstract
Purpose
This paper aims to analyze the morphology transformation on the Cu3Sn grains during the formation of full Cu3Sn solder joints in electronic packaging.
Design/methodology/approach
Because of the infeasibility of analyzing the morphology transformation intuitively, a novel equivalent method is used. The morphology transformation on the Cu3Sn grains, during the formation of full Cu3Sn solder joints, is regarded as equivalent to the morphology transformation on the Cu3Sn grains derived from the Cu/Sn structures with different Sn thickness.
Findings
During soldering, the Cu3Sn grains first grew in the fine equiaxial shape in a ripening process until the critical size. Under the critical size, the Cu3Sn grains were changed from the equiaxial shape to the columnar shape. Moreover, the columnar Cu3Sn grains could be divided into different clusters with different growth directions. With the proceeding of soldering, the columnar Cu3Sn grains continued to grow in a feather of the width growing at a greater extent than the length. With the growth of the columnar Cu3Sn grains, adjacent Cu3Sn grains, within each cluster, merged with each other. Next, the merged columnar Cu3Sn grains, within each cluster, continued to merge with each other. Finally, the columnar Cu3Sn grains, within each cluster, merged into one coarse columnar Cu3Sn grain with the formation of full Cu3Sn solder joints. The detailed mechanism, for the very interesting morphology transformation, has been proposed.
Originality/value
Few researchers focused on the morphology transformation of interfacial phases during the formation of full intermetallic compounds joints. To bridge the research gap, the morphology transformation on the Cu3Sn grains during the formation of full Cu3Sn solder joints has been studied for the first time.