Green Mode Research Articles

Simultaneous homogeneous liquid–liquid microextraction and dispersive liquid–liquid microextraction for extraction of some plasticizers from polymeric containers and aqueous samples

ABSTRACT A green mode of simultaneous homogeneous liquid–liquid microextraction combined with dispersive liquid–liquid microextraction assisted by sodium sulphate has been developed for the extraction and pre-concentration of some phthalate esters and di-(2-ethylhexyl) adipate from different aqueous samples prior to their determination by gas chromatography-mass spectrometry. In this method, an appropriate mixture of sodium sulphate solution (phase separation agent and disperser solvent) containing iso-propanol (extraction solvent) is hastily injected into an aqueous solution containing sodium sulphate and selected analytes. By doing so, the extractant is dispersed as tiny droplets into the aqueous phase. After centrifuging extractant containing the analytes is collected on the top of the aqueous phase. Under the optimum conditions, limits of detection and quantification were obtained in the ranges of 14–33, and 47–110 ng L–1, respectively. The enrichment factors and extraction recoveries of the phthalate esters ranged from 395 to 470 and 79–94%, respectively.

Green mode synthesis of silver nanoparticles using Vitis vinifera’s tannin and screening its antimicrobial activity / apoptotic potential versus cancer cells

A green synthesis was employed to prepare silver nanoparticles via reduction of silver nitrate, by utilize Vitis vinifera fruit skin extract as reductant. The results evident that the silver nanoparticles were well formed, when mixing the methanolic Vitis vinifera fruit skin extract with silver nitrate. The resultant silver nanoparticles was duly characterized via Fourier-transform infrared spectroscopy (FTIR), UV–vis spectrophotometer, transmission electron microscopy (TEM) techniques and scanning electron microscopy equipped with Energy-dispersive X-ray spectroscopy (SEM/EDX). Further, silver nanoparticles size was measured through SEM, TEM and Zeta potential analysis. The functional group of organic molecules (over Vitis vinifera extract), which is liable for the reduction of silver ions was confirmed through FT-IR analysis. The Vitis vinifera extract and its respective silver nanoparticles produced were investigated for its antimicrobial activity against pathogenic bacteria viz., Staphylococcus epidermidis, Staphylococcus aureus and Listeria monocytogenes. The results evident the silver nanoparticle’s noteworthy antimicrobial potential against all screened bacteria. Further, anticancer screening of silver nanoparticles found effectively inhibit the proliferation of cancer cells (HeLa and MCF-7 cells).

Exploring the Impact of Dockless Bikeshare on Docked Bikeshare—A Case Study in London

As a green and sustainable travel mode, the bikeshare plays an important role in solving the “last-mile” problem. The new dockless bikeshare system (DBS) is widely favored by travelers, and the traditional docked bikeshare system (BS) is affected to a certain extent, but the specific circumstances of this impact are not yet known. To fill the knowledge gap, the objective of this study is to measure the impacts of DBS on London cycle hire, which is a type of BS. In this study, the travel data of 707 docking stations in two periods, i.e., March 2018 and March 2017, are included. A spatial-temporal analysis is first conducted to investigate the mobility pattern changes. A complex network analysis is then developed to explore the impact of DBS on network connectivity. The results suggest a significant decrease of 64% in the average trip amounts, with both origins and destinations in the affected area, and the trips with short and medium duration and short and medium distances are mainly replaced by DBS. DBS also has a considerable impact on the structure and properties of the mobility network. The connectivity and interaction strength between stations decrease after DBS appears. We also concluded that the observed changes are heterogeneously distributed in space, especially on weekends. The applied spatial-temporal analysis and complex network analysis provide a better understanding of the relationships between DBS and BS.

A novel method for green delivery mode considering shared vehicles in the IoT environment

PurposeIncreasing academic communities and practitioners begin to explore a novel method to reduce environmental pollution and realize green logistics delivery. Additionally, China's Statistical Yearbook shows that the number of private cars has reached 165 million in China. Under this background, this study proposes a green delivery method by the combination of sharing vehicle (private cars) and IoT (Internet of things) from the perspective of vehicle energy efficiency and aims to improve the energy efficiency of social vehicles and provides more convenient delivery services.Design/methodology/approachThis study builds an IoT architecture consisting of customer data layer, information collection layer, cloud optimization layer and delivery task execution layer. Especially in the IoT architecture, a clustering analysis method is used to determine the critical value of customers' classification and shared delivery, a routing optimization method is used to solve the initial solution in could layer and shared technology is used in the implementation of shared delivery.FindingsThe results show that the delivery method considering shared vehicles has a positive effect on improving the energy utilization of vehicles. But if all of delivery tasks are performed by the shared vehicle, the application effect may be counterproductive, such as delivery cost increases and energy efficiency decreases. This study provides a good reference for the implementation of green intelligent delivery business, which has a positive effect on the improvement of logistics operation efficiency.Originality/valueThis study designs a novel method to solve the green and shared delivery issues under the IoT environment, which integrates the IoT architecture. The proposed methodology is applied in a real case in China.

Optimizing bike sharing systems from the life cycle greenhouse gas emissions perspective

Bike sharing systems (BSSs), being viewed as providing green transportation modes, are growing rapidly in recent years. While BSS operators try to improve the system performance through bike rebalancing and launching more bikes, the current BSSs are facing several sustainability challenges. Bike oversupply could bring intensive greenhouse gas (GHG) emissions due to manufacturing excessive bikes, while frequent bike rebalancing could significantly increase fuel consumption of rebalancing vehicles. Existing studies only optimized given BSS from the system operational perspective (i.e. rebalancing), with predetermined bike fleet size and rebalancing frequencies. However, the bike fleet size and rebalancing should also be optimized from the life cycle’s perspective. This study proposes a framework to obtain the optimal bike fleet size and rebalancing strategy to minimize the system’s life cycle GHG emissions, integrating a simulation model for fleet size estimation, an optimization model for bike rebalancing, and a life cycle assessment (LCA) model to quantify the system’s GHG emission rate. The framework is applied to a dock-less BSS in Xiamen, China as a case study to evaluate the tradeoff between having more bikes (requiring less rebalancing) and more frequent rebalancing (requiring fewer bikes). Our results show that (1) the current BSS in Xiamen is significantly oversupplied, with only 15% of current bikes needed to serve the same demands; (2) decreasing bike fleet size through more frequent rebalancing will increase the system’s life cycle GHG emissions; and (3) choosing appropriate rebalancing fleet size, loading capacity, and setting multiple depots can reduce a BSS’ rebalancing GHG emissions.

A study on the Current Situation and Countermeasures of Green Travel for College Students

With the rapid development of urbanization, a number of problems such as traffic congestion and air pollution are becoming more and more serious. Green travel is an important part of urban planning, which can effectively alleviate environmental pollution. As an important part of urban population, college students have distinct characteristics in travel demand, travel mode, and other aspects. Their cognition of green travel also has a tremendous impact on urban traffic planning and development. Taking Shandong Agricultural University as a case study, this study investigated the green travel situation of college students in the form of questionnaire, and analyzed their travel characteristics and influencing factors. Most people think that when dealing with the traffic problems, the government should play a major role and put forward rectification measures; in the existing green travel mode, the use frequency of bicycles or electric vehicles is not very high, and there are many problems in the use process; for short-distance travel, many people use walking or co-riding, etc. After analyzing the relevant factors, this study proposed targeted measures to encourage and guide students to choose green travel.

Green Collaborative Development Model and Innovation of Port Machinery Manufacturing Industry and Service Industry

Nie, X., 2020. Green collaborative development model and innovation of port machinery manufacturing industry and service industry. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 278–283. Coconut Creek (Florida), ISSN 0749-0208.The existing green collaborative development mode and innovative research method are easily interfered by subjective randomness when calculating the green collaborative coefficient, resulting in the final moderate measurement value is too small. To solve this problem, a green collaborative development mode and innovative research method of port machinery manufacturing industry and service industry are proposed. The two industry development model is determined, and the long tail theory is used to plan the collaborative development industry chain, and the collaborative innovation value is calculated. By using the weight of green synergy coefficient modified by entropy method, the innovative research on the green synergy development mode of port machinery manufacturing industry and service industry is completed. The experimental results show that the appropriate measurement value of the research method in this paper is greater than 0.9, and the value is significantly greater than that of the two traditional research methods.

Exploring the Relationship between Transport Interventions, Mode Choice, and Travel Perception: An Empirical Study in Beijing, China.

Transport interventions help to facilitate the sustainable travel behavior. The effects of transport interventions on travel choices have been addressed extensively. However, little research has been devoted to the influence of transport interventions and travel choice on travel perception. This study aimed to investigate the relationship among the three aspects. Two intervention measures, information intervention and public transport service improvement, were selected. Intervention experiments were designed to collect mode choice and corresponding travel perception in different experiment stages. Process models of information intervention and public transport service improvement were proposed. The results show that information intervention only had a minor effect on mode choice and had no direct effect on travel perception. Public transport service improvement in in-vehicle time and comfort enhanced public transport use dramatically. Comfort improvement also had positive effects on travel perception. Walking had positive and public transport trips had negative effects on travel perception. For travelers who had a high evaluation of car trips, the probability of green mode use would decrease. Travelers who gave high marks to trips by green mode would have a higher probability to keep traveling by green mode. This study contributes to facilitating public transport use and enhancing positive perception during traveling.

China’s Transition to Green Development: Process, Challenges and Responsive Measures

Since the reform and opening up, China has made unremitting explorations of a transition to green development and promoted economic development to get rid of dependence on high consumption, high emissions and environmental damage, and shift to a green development mode that can help in the mutual promotion between economic growth and resource conservation, emission reduction and environmental improvement. This paper elaborates China’s progress and challenges in its transition to green development and provides responsive measures for future green transformation with Chinese characteristics.

A Traffic Simulation Tool for Assessing Smart City Policies (CitScale)

The CitScale visualization and analytics platform has proven to be very practical in supporting the results analyses for different experimental designs. The designs applied here incorporated different traffic simulation models for various purposes. A project for probe vehicle data assessment has been incorporated into CitScale, as well as another project that focuses roughly on analyzing the impact of emissions in the Eixample on KPIs, specifically when the city shifts to more green modes such as bicycles or electric vehicles. A further development for improving demand modeling in CitScale will provide representations of activity -based demand. This flexible tool will save a lot of time for traffic analysts and future transportation projects at the UPC.

Green synthesis of iron oxide nanoparticles using Hibiscus rosa-sinensis for fortifying wheat biscuits

The present investigation is an attempt on synthesising iron oxide nanoparticles through greener mode using the petal extracts of Hibiscus rosa-sinensis and utilising them as fortificants in wheat biscuits. Ferric and ferrous chloride at a concentration of 0.025 M and at a ratio of 2:1 was used as the metal precursors and the extract was served as the reducing agent. Synthesised iron oxide nanoparticles were characterised using UV–visible spectroscopy, X-ray diffraction (XRD), FTIR spectroscopy and scanning electron microscopy (SEM). The analyses confirmed that the formed particles were nano sized and the crystallite size was found to be 6.16 nm through XRD studies. The formed nanoparticles were observed from SEM analysis to be spinel shaped with an average particle size of 65 nm. Biscuits were fortified with iron oxide nanoparticles which were later studied for physical and proximate analyses. The inductively coupled plasma optical emission spectroscopy studies revealed that the iron content was higher in fortified biscuits than that in control. Microbial analysis for 30 days indicated that the fortified biscuits could have a longer shelf life. In brief, the first report on use of iron oxide nanoparticles successfully suggested that their use as fortificants in food and could be prescribed for malnourished, iron deficit or anaemic patients.

What Hinders the Promotion of the Green Mining Mode in China? A Game-Theoretical Analysis of Local Government and Metal Mining Companies

China is currently trying to reduce the environmental impact of metal mining operations by promoting green mining. However, conflicts of interest between the central government, local governments, and metal mining companies often negatively affect the implementation of related policies. This paper conducted a theoretical analysis of the game mechanism between local governments and metal mining companies to study the factors that influence their strategies. First, we summarize the various game model parameters, determine the strategies which the companies and local government can choose, and establish the game model for the companies and the local government. Second, we list the utility of the company and local government under all game outcomes and analyse their behavioral tendencies. Third, we discuss the impacts of various factors on the choice of their mining mode in detail. The behavioral analysis shows that the local government’s inclination to supervise a mine is negatively related to the supervision cost and positively related to the production scale of this mine; various factors influence the companies in their decision making, with the yield and comprehensive utilization rate of tailings and waste rocks have the greatest impact; the scale of mine production also affects the companies’ willingness to carry out technological innovation. Finally, we offer some suggestions for the promotion of green mining.

Development of organic solvents-free mode of solidification of floating organic droplet-based dispersive liquid-liquid microextraction for the extraction of polycyclic aromatic hydrocarbons from honey samples before their determination by gas chromatography-mass spectrometry.

In this study, a green mode of solidification of floating organic droplet-based dispersive liquid-liquid microextraction has been developed for the extraction of 16 polycyclic aromatic hydrocarbons from honey samples before their determination by gas chromatography-mass spectrometry. In this method, an appropriate volume of menthol:decanoic acid deep eutectic solvent (as an extraction solvent) is added on a sugar cube (as a disperser agent). In the following, the cube is released into the diluted honey sample placed in a tube. After manual shaking a cloudy state is obtained as a result of dispersing the extraction solvent droplets throughout the sample solution and the analytes are extracted into them. After placing the tube in an ice bath, the droplet of the extractant is solidified on the top of the solution. This drop is taken and after dissolving in acetonitrile, an aliquot of the solution is injected into the separation system. Under optimum conditions, the suggested approach had high extraction recoveries (76-93%) and enrichment factors (380-465), low limits of detection (14-52ng/kg) and quantification (47-173ng/kg), and satisfactory repeatability (relative standard deviation ≤ 9%).

Environmental concerns and switching toward electric vehicles: geographic and institutional perspectives.

Smog pollution deteriorates environmental quality and has severe health risks. This affects the daily lives of people in China, particularly in urban areas. Along with other factors, a large portion for smog comes from transportations, making it dense and more hazardous in urban areas. The Chinese government aims to reduce air pollution by promoting electric vehicles and green modes for mobility along with other environmental protection measures. The study explores the switching intentions of people from motorized vehicles to electric vehicles by integrating push-pull-mooring model and institutional theory. The study incorporates environmental quality, regulative environment, alternative attractiveness, normative environment, self-(decision)efficacy, and willingness to pay into an integrated framework. The study further analyzes the green behavior of consumers by extending switching intentions for electric vehicles. The integrated framework explains mooring as the most influential factor followed by normative environment from pull factors and environmental quality from push factors. The effect of regulative environment remains weak and significant, but the effect of alternative attractiveness remains weak and insignificant. The switching intentions strongly and significantly explain green behavior. Furthermore, mooring moderates the relationship between push factors, some of the pull factors, and switching intentions.

Green subsidy modes and pricing strategy in a capital-constrained supply chain

This paper investigates green credit (GC), manufacture subsidy (MS), and sales subsidy (SS) modes in a supply chain with a capital-constrained green manufacturer and attempts to find the win-win subsidy mode. We show that when the bank loan is infinite and the total subsidies of different modes are equal, GC can bring the highest returns with respect to green degree, market demand, social welfare, and environmental benefit. However, under the finite loan scenario, GC is the optimal choice for the government only when the credit line of the manufacturer is relatively high; otherwise, MS is the optimal subsidy mode.

Green Innovation Mode under Carbon Tax and Innovation Subsidy: An Evolutionary Game Analysis for Portfolio Policies

Previous literature has shown that manufacturers’ choices between radical and incremental green innovation modes can greatly impact the tradeoff between industry growth and carbon emission reduction. Yet, how the government can motivate manufacturers to implement radical green innovations to reduce carbon emission is unclear. In this paper, the researchers construct an evolutionary game model to analyze the joint impacts of carbon tax and innovation subsidy on manufacturers’ choices of green innovation mode. We derive the conditions for manufacturers’ stable strategies. Based on those results, we find that four factors—carbon tax, innovation subsidy, consumer green preference, and manufacturers’ capabilities of absorbing and adopting new technologies—may facilitate the choice of radical innovation. Furthermore, we conduct numerical simulations to verify the theoretical results, and further illustrate how the synergy of carbon tax rate and subsidy level affects the evolution of the green innovation mode choices. Specifically, we demonstrate the superiority of portfolio policy in the early stage of green innovation over single policy. In contrast, in the later stage, it is carbon tax but not innovation subsidy that remains effective. We discuss the insights for the government to formulate appropriate environmental policies to effectively promote the adoption of green innovation and reduce carbon emission.

Decision-Making of Green Space Utilization and Protection in Urban Fringe Based on Biodiversity Trade-Off

Urbanization leads to the continuous expansion of urban built-up areas and the erosion of green space in urban fringe areas, leading to the continuous decline of biodiversity. Urban planners and managers need corresponding decision support tools to coordinate the contradiction between the utilization and protection of green space, ensure the maintenance capacity of biodiversity in green space, and realize the sustainable development of regional economy, society and ecology. Therefore, based on the Hellwig Method, this study designed a decision-making method of green space utilization and protection in urban fringe areas and applied the method to the decision simulation of single or multiple green space utilization and protection modes. In the decision simulation of a green space utilization mode, we evaluated the Hk values of one or several green space sample units, respectively. The smaller the Hk value, the smaller the influence of the green space unit on the biodiversity maintenance function of the whole green space in the region, so the green space unit can be selected first when making green space utilization planning decisions in the urban fringe. In the decision simulation of green space protection mode, the higher the Hk value of single green space sample unit combination or multiple green space sample unit combination, the greater the influence of the green space unit in the combination on the maintenance function of the overall green space biodiversity in the region. Then, when planning the green space protection in the urban fringe, the combination of such green space sample units should be given priority as the key protection and control objects. As a decision support tool for optimal scheme of green space utilization and protection in urban fringe areas, the method is practical, instructive, reasonable, operable, flexible, and universal.

How Downplaying Product Greenness Affects Performance Evaluations: Examining the Effects of Implicit and Explicit Green Signals in Advertising

Despite frequent reports that they favor products with environmental benefits, consumers often purchase conventional alternatives. One reason for this is the performance liability associated with green products, in which consumers perceive them as being less effective. This research examines the concept of “green understatement” (i.e., communication of implicit green signals) compared with “green emphasis” (i.e., communication of explicit green signals) in green product advertising as a strategy to enhance performance evaluations. We test whether, why, and when an implicit (versus explicit) advertising strategy leads to higher performance evaluation for green products. We suggest and show that implicit green signals are more effective in conditions under which consumers have more concerns about the product’s performance or have lower expectations about its greenness. More specifically, the results of two experimental studies show that implicit (versus explicit) communication about greenness leads to higher performance evaluations for products that are less commonly green (Study 1) and for products that have an optional green mode (Study 2). The findings aid in the understanding of how a green product advertising strategy may influence performance evaluations and provide managerial implications for green product promotion.

Understanding intra-urban human mobility through an exploratory spatiotemporal analysis of bike-sharing trajectories

ABSTRACT In this paper, we present a data-driven framework to support exploratory spatial, temporal, and statistical analysis of intra-urban human mobility. We leveraged a new mobility data source, the dockless bike-sharing service Mobike, to quantify short-trip transportation patterns in Shanghai, China, the world’s largest bike-share city. A data-driven framework was established to integrate multiple data sources, including transportation network data (roads, bikes, and public transit), road characteristics, and urban land use, to achieve a detailed, accurate analysis of cycling patterns at both the individual and group levels. The results provide a comprehensive view of mobility patterns in the use of shared-ride bicycles, including: (1) the temporal and spatiotemporal distribution of shared-bike usage and how this varies according to different land use; (2) the statistical distribution of Mobike trips, which are primarily short-distance; and (3) the travel behavior and road factors that influence Mobike users’ route choice. The findings offer valuable insights for city planners regarding infrastructure development, for shared-ride bike companies to offer better bike rebalancing strategies to meet user demand, and for the promotion of this new green transportation mode to alleviate traffic congestion and enhance public health.

A sustainability comparison between green concretes and traditional concrete using an emergy ternary diagram

The sustainable development of green concrete consumes as few natural resources as possible during production and uses and utilizes recyclable waste materials as raw materials. This study summarizes three modes of green concrete production: recycled aggregate concrete production mode, fly ash concrete production mode, and circular economy concrete production mode, as well as the system emergy flow of each mode of production, and presents emergy analysis methods for each mode. With the help of emergy ternary diagram auxiliary lines, the emergy ternary diagram expressions of three green concrete production modes and traditional concrete production modes are analyzed, respectively. The ternary diagram of emergy analysis directly reflects the resource allocation of the system. The relationship between the emergy utilization ratio and the indicators of the system is analyzed, and the sustainability of the existing concrete production system is evaluated comprehensively. The R-resource line corresponds to the environmental load ratio. The closer the R-resource line is to the F-axis, the greater the environmental pressure of the system. The N-resource line corresponds to emergy yield ratio and emergy investment ratio. The closer the N-resource line is to the N-axis, the greater the energy input-output efficiency of the system. The closer the N-resource line is to the “0” point of the R-axis, the higher the utilization rate of outsourced resources. In the emergy ternary diagram, it is evident that the circular economy concrete production mode is more sustainable than the other three concrete production modes. Combined with the analysis of the sensitivity line and sustainability line, it is predicted that the concrete production mode along the direction of the R-Sensitivity line is a sustainable development path.