67 research outputs found
Simulation on Phase Change Thermal Storage Panel Based on Capillary Network
AbstractStorage technology has the advantage to solve the problem of the not matching in time and space of energy's supply and demand, making it an effective way to the rational use of resources and reducing environmental pollution. What is used in this paper is a regular flat phase change heat storage module packaging with capillary network and phase change material. In this paper, the software Fluent was used to simulate the impact factors and the ways to enhance heat transfer in the process of phase change. The simulation result indicates that: During the melting process, because of the influence of natural convection, the top of phase change regional melts faster, the temperature contour ramp to top. The higher the horizon is, the temperature contour is more stable. Natural convection play different role in the melting and solidification process, which accelerated melting rate in the melting process, and slowed down in solidification. The surface temperature of phase change thermal storage panel will be maintained at 26.5°C, within the limits of human body comfort and is able to improve the air temperature within a certain space
Purification, composition analysis and antioxidant activity of different polysaccharides from the fruiting bodies of Pholiota adiposa
Three water-soluble polysaccharide fractions (PAP1-1, PAP1-2 and PAP2-1) were isolated and purified from the fruiting bodies of Pholiota adiposa by diethylaminoethanol (DEAE) Sepharose fast flow column and superdexTM 200 column chromatography on an AKTA Purifier system. Results of high-performance size-exclusion chromatography (HPSEC) indicated that the average molecular weights of PAP1-1, PAP1-2 and PAP2-1 were 2.3 x 106 Da, 8.8 x 103 Da and 2.1 x 106 Da, respectively. Monosaccharide compositions analysis revealed that PAP1-1 and PAP2-1 were both mainly composed of glucose, and PAP1-2 was composed of rhamnose and glucose with a mole ratio of 1:3.61. The evaluation of antioxidant activity suggested that PAP1-1 with β-configuration glycosidic bond exhibited stronger scavenging activity of superoxide radical and hydroxyl radical than PAP1-2 and PAP2-1 contained both α- and β-configuration glycosidic bond, and should be explored as a novel potential antioxidant. Available data obtained with in vitro models suggested that antioxidant activity of polysaccharide may be related to the configuration of glycosidic bond.Key words: Pholiota adipose, polysaccharide, purification, antioxidant activity
Baicalin Attenuates Oxygen–Glucose Deprivation/Reoxygenation–Induced Injury by Modulating the BDNF-TrkB/PI3K/Akt and MAPK/Erk1/2 Signaling Axes in Neuron–Astrocyte Cocultures
Background: Baicalin (BCL), a candidate drug for ischemic stroke, has been indicated to protect neurons by promoting brain-derived neurotrophic factor (BDNF). However, the cellular source of BDNF release promoted by baicalin and its detailed protective mechanism after ischemia/reperfusion remains to be studied. The aim of this study was to investigate the neuroprotective mechanisms of baicalin against oxygen–glucose deprivation/reoxygenation (OGD/R) in a neuron–astrocyte coculture system and to explore whether the BDNF-TrkB pathway is involved.Methods and Results: A neuron–astrocyte coculture system was established to elucidate the role of astrocytes in neurons under OGD/R conditions. The results demonstrated that astrocytes became reactive astrocytes and released more BDNF in the coculture system to attenuate neuronal apoptosis and injury after OGD/R. BCL maintained the characteristics of reactive astrocytes and obviously increased the expression of cyclic AMP response element-binding protein (CREB) and the levels of BDNF in the coculture system after OGD/R. To further verify whether BDNF binding to its receptor tyrosine kinase receptor B (TrkB) was required for the neuroprotective effect of baicalin, we examined the effect of ANA-12, an antagonist of TrkB, on NA system injury, including oxidative stress, inflammation, and apoptosis induced by OGD/R. The results showed that treatment of NA systems with ANA-12 significantly attenuated the neuroprotection of BCL. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathways are two important downstream cascades of signaling pathways activated by BDNF binding to TrkB. We investigated the expressions of TrkB, PI3K, Akt, MAPK, and ERK. The results demonstrated that baicalin significantly increased the expressions of TrkB, PI3K/AKT, and MAPK/ERK.Conclusion: The neuroprotective effects of baicalin against oxidative stress, inflammation, and apoptosis were improved by astrocytes, mainly mediated by increasing the release of BDNF and its associated receptor TrkB and downstream signaling regulators PI3K/Akt and MAPK/ERK1/2
Evaluating the Effects of Logistics Center Location: An Analytical Framework for Sustainable Urban Logistics
Sustainable urban logistics require support of sustainable logistics center location planning. Nevertheless, urban public authorities generally experience difficulties in choosing a successful planning scheme, due to the lack of a rigorous analytical tool designed to help understand how logistics center location affects sustainability throughout the supply chain. A poor location can keep a firm or a supply chain from reaching its economic, environmental, and social sustainability goals. A good location can help meet these goals. To address the pressing cause of policy failure, this paper developed an analytical framework by integrating the multi-criteria decision-making method and the shortest path model with multiple objectives. The developed framework can be used to evaluate the effects of logistics center location schemes on travel time, transport costs, carbon emission, and road traffic, and further explore the conflict level among them. It is applied to Beijing in this paper. The analysis results reveal that: (1) travel time, transport costs, and carbon emissions all vary along with the distance from logistics center location to the city center; (2) encouraging cargo companies to plan their truck paths with the navigation objective of minimizing travel time is an excellent way to achieve sustainable urban logistics, because in this scenario, freight transport is the quickest, and transport costs and carbon emissions are all more moderate. Additionally, this paper confirmed the conflict level among sustainability goals of urban logistics based on actual contextual data. The proposed framework is a helpful guide tool for urban planners to develop sustainable logistics land-use planning and responsive policy interventions
A study on optimization of delayed production mode of iron and steel enterprises based on data mining
Delayed production mode has been adopted by an increasing number of process production enterprises as a method to realize mass customization of multi-products. This paper used the convolutional neural network-long short-term memory artificial neural network algorithm (C-LSTM) in data mining technology to analyze and determine factors that have an impact on delayed production mode in the internal and external production and operation of enterprises. Combined with the actual production situation of iron and steel enterprises, a quantitative model of the delayed production was constructed. Lastly, data from a large iron and steel enterprise with good operation was used to verify the validity of the proposed model and analyze key influencing factors. According to the research, in scenarios of considering PDP alone, considering CODP alone, considering both PDP and CODP, considering PDP and CODP and using data mining technology to model, the matching degree of these methods with the actual situation of the enterprise is 31.8%, 61.4%, 71.6% and 86.6%, respectively. The numerical analysis results of the model based on data mining technology show that in delayed production, when customer service level improves or the delay penalty coefficient increases, the optimal locations of the product differentiation point (PDP) and customer order decoupling point (CODP) move toward the end of production, and the total cost increases gradually. When the difference in production cost or benefit of early delivery between the candidate locations of PDP and CODP is small, optimal locations of PDP and CODP are close to the beginning of the general and dedicated production processes. With an increase of cost difference or early delivery benefit, the optimal locations of PDP and CODP jumped to the end stage of the general and dedicated production processes, and the total cost begins to decrease
Evaluating the Effects of Logistics Center Location: An Analytical Framework for Sustainable Urban Logistics
Sustainable urban logistics require support of sustainable logistics center location planning. Nevertheless, urban public authorities generally experience difficulties in choosing a successful planning scheme, due to the lack of a rigorous analytical tool designed to help understand how logistics center location affects sustainability throughout the supply chain. A poor location can keep a firm or a supply chain from reaching its economic, environmental, and social sustainability goals. A good location can help meet these goals. To address the pressing cause of policy failure, this paper developed an analytical framework by integrating the multi-criteria decision-making method and the shortest path model with multiple objectives. The developed framework can be used to evaluate the effects of logistics center location schemes on travel time, transport costs, carbon emission, and road traffic, and further explore the conflict level among them. It is applied to Beijing in this paper. The analysis results reveal that: (1) travel time, transport costs, and carbon emissions all vary along with the distance from logistics center location to the city center; (2) encouraging cargo companies to plan their truck paths with the navigation objective of minimizing travel time is an excellent way to achieve sustainable urban logistics, because in this scenario, freight transport is the quickest, and transport costs and carbon emissions are all more moderate. Additionally, this paper confirmed the conflict level among sustainability goals of urban logistics based on actual contextual data. The proposed framework is a helpful guide tool for urban planners to develop sustainable logistics land-use planning and responsive policy interventions
Data mining analysis results of the impact of production and operation factors on delayed production control.
Data mining analysis results of the impact of production and operation factors on delayed production control.</p
Influence of production cost difference between CODP candidate locations on total cost and the optimal location of CODP.
Influence of production cost difference between CODP candidate locations on total cost and the optimal location of CODP.</p
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