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Reliable forecast of municipal solid waste (MSW) generation is crucial for sustainable and efficient waste management. Big data analysis is a novel method to forecast MSW more accurately. Thus, this study employs five kinds of supervised machine learning approaches including linear regression, polynomial regression, support vector machine, random forest, and extreme gradient boosting (XGBoost) to examine their forecast performances. China's MSW generation from 2020 to 2060 under five shared socioeconomic pathways (SSPs) is further predicted and the mechanisms between MSW generation and socioeconomic features are explored. Results show that population and GDP are two dominant indicators in MSW prediction, and XGBoost model is proved to be effective in MSW forecast. MSW generation of China in 2060 is estimated to be 464-688 megatons under different SSPs scenarios, about four to six times of that in 2000. SSP3 that has the most population, least GDP and the highest climate change challenges is the only scenario showing a potential of MSW peak during the study period. The key for MSW increase is mainly the increase of per capita MSW caused by GDP. Finally, several policy recommendations are raised to reduce the overall MSW generation.

Background Eczema is a chronic inflammatory disease associated with impaired quality of life. We identified indoor environmental risk factors, to provide strong evidence for the prevention and control of eczema in preschool children. Methods Using a cross-sectional study with stratified random cluster sampling, we conducted a self-administered questionnaire survey among 8153 parents of children aged 2–8 years in 60 kindergartens in six districts of Urumqi city during August 2019. Results Among 8153 preschool children, 12.0% of the children have been diagnosed with eczema. Multivariate logistic regression analysis showed that caesarean section (odds ratio [OR] = 1.18, 95% confidence interval [CI]: 1.03–1.36), being an only child (OR = 1.36, 95% CI: 1.18–1.57), presence of mould or moisture in the mother’s home before pregnancy (OR = 1.53, 95% CI: 1.17–2.00), presence of flies or mosquitoes in the dwelling currently (OR = 1.31, 95% CI: 1.10–1.55), pets kept in the child’s home currently (OR = 1.23, 95% CI: 1.01–1.51), presence of pets during child’s first year (OR = 1.45, 95% CI: 1.14–1.85), and family history of eczema (OR = 3.53, 95% CI: 2.98–4.19) are the risk factors for the development of eczema, whereas ethnicity other than the Han Chinese (OR = 0.77, 95% CI: 0.61–0.96) is a protective factor for eczema. Conclusion Preschool children in Urumqi are at a high risk of eczema, particularly those of the Han Chinese ethnicity. Parents should be attentive to the indoor living environment of children and take actions to reduce indoor humidity, pest control and elimination, and avoid raising pets to reduce the risk of development of eczema in children.

Many water footprint studies have been conducted on those water scarce regions to respond their water crisis, while water rich regions also face water sustainability challenges due to inadequate water management or being virtual water exporter. Therefore, this paper tries to clarify the water footprint and detail virtual water flow features of a water-rich province, namely Yunnan province in China, to pursuit for more enlightenment for water conservation of not only water scarce regions but also water abundant regions. Multi-regional input-output (MRIO) method was adopted for water footprint and virtual water flow calculation. Results showed that the total water footprint of Yunnan was 11.35 billion m3, with 7.98 billion m3 (70%) of internal water footprint, demonstrating that Yunnan was a high water self-sufficient province. Moreover, Yunnan was a net virtual water exporter with a value of 1.18 billion m3, which was not good for Yunnan but was good for water scarce provinces. As for the detailed virtual water flow trade, high water intensity Guangxi, Hunan, Xinjiang were the top three net importers of Yunnan, while low water intensity Guangdong, Shanghai and Zhejiang were the top three export provinces of Yunnan. This did not affect Yunnan, but was not a good phenomenon for water sustainability of whole China. Moreover, agricultural sector was found to be the dominant sector for both virtual water import and export, accounting for about 88% and 86%, respectively. To maintain sustainable water management of both Yunnan and China, policy insights on keeping Yunnan as a net virtual water exporter, making use of its advantage in green water, adjusting trade structure by considering provincial water intensity were proposed.

Grey water footprint (GWF), as a measure of water pollution in terms of the amount of water needed to dilute pollutants, has drawn great attention due to the necessity to respond to water contamination and water scarcity challenges. Under such a circumstance, this study aims to reveal China's national and provincial GWF features from 2003 to 2015, and to identify the corresponding driving forces by using the Kaya equation and the Logarithmic Mean Division Index (LMDI) decomposition method. Results show that the national total GWF declined from 1418 billion m3 in 2003 to 1655 billion m3 in 2015, and the industrial GWF reduction was the main reason for this decrease. Domestic GWF was the dominant component, particularly for service dominated provinces such as Beijing, Shanghai, Hainan, etc., with proportion up to about 80%. Southern and eastern provinces had higher GWF but lower GWF intensity (GWF per unit GDP), and water scarce northern provinces exhibited higher GWF load although they had lower GWF. The GWF intensity experienced a decreasing trend, with economy effect and intensity effect being the main driving forces, particularly for Tibet. Technology effect and exploitation effect (ratio of water use to water resource) were the main barriers for less developed provinces. Finally, policy recommendations are proposed to alleviate future GWF challenges of China, such as improving the discharge standards of WWTP (wastewater treatment plant), promoting wastewater recycling, reducing GWF intensity and GWF load through industrial structure and trade structure adjustment.

Interaction behaviors are a crucial, distinctive feature of organisms in ecological systems. Inspired by nature, micro-/nanorobots also show interaction behaviors with a significant number of novel and advanced functionalities. The micro-/nanoscale size and self-driven abilities of micro-/nanorobots have attracted considerable attention for potential applications. The mission of micro-/nanorobots has evolved from basic mechanical transfer or assistance to a diverse range of complex tasks, such as targeted drug delivery, biosensing, and environmental remediation. Herein, we focus on the interaction behavior of coexisting cooperative cognitive (Tri-Co) micro-/nanorobots, summarize recent research, and classify the interactions into three broad types: with the environment, with robot peers, and with human external control.

To move towards sustainable urban development, interactions between economic and ecological systems should be further investigated due to their coupled relations. In this study, we propose an emergy-based ecological footprint (EEF) analysis framework. Shanghai was selected as a case study city to see its dynamic changes from 2007 to 2016. The results show that Shanghai had a large ecological deficit, an extremely high ecological footprint intensity and a poor coordination relationship between its ecological system and its economic system, indicating a great ecological challenge that it is facing. The uneven distribution of its emergy ecological footprint is mainly due to the large share of fossil fuels land type. But with the city's great efforts, the overall ecological pressure has been reduced and the coordination relationship has also been improved, while the local economy is still booming. Pearson correlation analysis further indicates that the city's policy on developing tertiary industry has resulted in a positive effect on improving the coordinating relationship. The ratio between the output value of heavy industry and gross industrial output value has the most negative correlation with the coordinating relationship. Finally, policy recommendations are raised by considering the local realities. These recommendations can also provide valuable insights to other megacities with similar challenges.

The Pseudomonas putida F1 genome contains five genes annotated as encoding 3-ketoacyl-acyl carrier protein (ACP) synthases. Four are annotated as encoding FabF (3-ketoacyl-ACP synthase II) proteins, and the fifth is annotated as encoding a FabB (3-ketoacyl-ACP synthase I) protein. Expression of one of the FabF proteins, FabF2, is cryptic in the native host and becomes physiologically important only when the repressor controlling fabF2 transcription is inactivated. When derepressed, FabF2 can functionally replace FabB, and when expressed from a foreign promoter, had weak FabF activity. Complementation of Escherichia coli fabB and fabF mutant strains with high expression showed that P. putida fabF1 restored E. coli fabF function, whereas fabB restored E. coli fabB function and fabF2 restored the functions of both E. coli fabF and fabB. The P. putida ΔfabF1 deletion strain was almost entirely defective in synthesis of cis-vaccenic acid, whereas the ΔfabB strain is an unsaturated fatty acid (UFA) auxotroph that accumulated high levels of spontaneous suppressors in the absence of UFA supplementation. This was due to increased expression of fabF2 that bypasses loss of fabB because of the inactivation of the regulator, Pput_2425, encoded in the same operon as fabF2. Spontaneous suppressor accumulation was decreased by high levels of UFA supplementation, whereas competition by the P. putida β-oxidation pathway gave increased accumulation. The ΔfabB ΔfabF2 strain is a stable UFA auxotroph indicating that suppressor accumulation requires FabF2 function. However, at low concentrations of UFA supplementation, the ΔfabF2 ΔPput_2425 double-mutant strain still accumulated suppressors at low UFA concentrations.

Robust output-feedback torque controller is developed for series elastic actuators (SEAs) in the presence of parameter uncertainties and external disturbances. The strong robustness of the proposed controller results from the filter-based observer which can estimate the velocity signals and the system lumped disturbance. The dynamic surface method is adopted to make the time-domain controller independent of any derivatives of the command reference, making the torque controller an ideal building block for multi-level control frameworks. The semiglobal stability of the closed-loop control system is proven under the assumption that only the state-independent uncertainty is bounded. The experimental results verify the effectiveness of the torque controller, and the implementation of two-level control frameworks, including the impedance control and SEA’s load position control, further demonstrates its wide applicability.

High-entropy perovskite thin films, as the prototypical representative of the high-entropy oxides with novel electrical and magnetic features, have recently attracted great attention. Here, we reported the electronic structure and charge transport properties of sol-gel-derived high-entropy Ba(Zr0.2Sn0.2Ti0.2Hf0.2Nb0.2)O3 thin films annealed at various temperatures. By means of X-ray photoelectron spectroscopy and absorption spectrum, it is found that the conduction-band-minimum shifts downward and the valence-band-maximum shifts upward with the increase of annealing temperature, leading to the narrowed band gap. Electrical resistance measurements confirmed a semiconductor-like behavior for all the thin films. Two charge transport mechanisms, i.e., the thermally-activated transport mechanism at high temperatures and the activation-less transport mechanism at low temperatures, are identified by a self-consistent analysis method. These findings provide a critical insight into the electronic band structure and charge transport behavior of Ba(Zr0.2Sn0.2Ti0.2Hf0.2Nb0.2)O3, validating it as a compelling high-entropy oxide material for future electronic/energy-related technologies.

Lead-free dielectric thin-film capacitors with desirable energy storage density are gathering attention due to the increasing environmental concern and the integrating electronic devices. We here reported a series of new highly-orientated (1-x)NaNbO3-xBaHfO3 (x

Background: We explored the prevalence of eczema and indoor environmental factors in preschool children in Urumqi, Xinjiang, to provide a strong basis for the prevention and control of preschool eczema. Methods: Using stratified random cluster sampling, we conducted a self-administered questionnaire survey among 8153 parents of children aged 2–8 years in 60 kindergartens in six districts of Urumqi City during August 2019. Results: For the 8153 preschool children with valid data, the parent-reported prevalence of eczema was 12.0%. Multivariate logistic regression analysis showed that cesarean section (odds ratio [OR] = 1.18, 95% confidence interval [CI]: 1.03–1.36), being an only child (OR = 1.36, 95% CI: 1.18–1.57), mold or moisture in the mother’s residence before pregnancy (OR = 1.53, 95% CI: 1.17–2.00), flies or mosquitoes in the dwelling currently (OR = 1.31, 95% CI: 1.10–1.55), pets kept in the child’s current residence (OR = 1.23, 95% CI: 1.01–1.51), presence of pets when the child is 0–1 year old (OR = 1.45, 95% CI: 1.14–1.85), and family history of eczema (OR = 3.53, 95% CI: 2.98–4.19) are risk factors, whereas ethnicity other than Han Chinese (OR = 0.77, 95% CI: 0.61–0.96) is a protective factor, for eczema. Conclusion: Preschool children in Urumqi are at a high risk of eczema, especially those of Han Chinese ethnicity. Parents should pay close attention to the indoor living environment of children and must reduce indoor humidity, pay attention to pest control and elimination, and avoid raising pets to reduce the risk of children developing eczema.

Environmental damage cost can measure the impact of pollution caused by human activity on final safeguard subjects from endpoint perspective. Application of environmental damage cost to municipal solid waste (MSW) management is still rare. To fill such a research gap, this study established a MSW environmental damage cost assessment method using Life Cycle Impact Assessment Method based on Endpoint (LIME) model. Four types of environmental damage cost, namely, primary productivity, social assets, biodiversity and human health for waste treatment were investigated in the city of Shanghai. Results show that the environmental damage cost was 113.7, 116.9, 140.0, 144.0 and 170.8 million dollars in Shanghai from 2014 to 2018, respectively. Damage cost of social assets was the dominant component, accounting for about 55%. Landfill mainly caused social assets damage cost, while incineration mainly caused human health damage cost. Scenarios analysis further revealed that after implementing MSW separation, the total environmental damage cost could be reduced by about 1/3. The best MSW treatment method is fermentation, followed by compost, incineration and landfill, with unit environmental damage cost being 0.22, 4.51, 16.04 and 23.47 USD/ton, respectively.

Zinc dyshomeostasis is a major mechanism of neuronal death, which is involved in many different neuropathological conditions. Lysosomal membrane permeabilisation has an important function in zinc-induced neuronal death under oxidative stress. To investigate lysosomal zinc functions in neurons with high spatial and temporal reliability, we report a ratiometric probe, LysoZn-1. It is derived from the styryl-BODIPY-DPA scaffold with a lysosome-targeted 2-morpholinoethylamine moiety to allow localisation in lysosomes. The electron donor at the meso-position of the BODIPY fluorophore makes the present probe prefer complexing with Zn

Year 2005 is important because it is the base year for the international carbon reduction commitment and national development plans for China. However, accurate and robust CO2 emission data for 2005 remain limited, particularly for city-level emissions. To address these gaps, we established a uniform city-level CO2 emission inventory for all the 287 prefecture-level cities in China for 2005, combining the High-Resolution Emission Gridded Database (CHRED) 2.0, statistical data and onsite survey. The results showed that Shanghai, Tangshan, Beijing, Tianjin, Jining, Handan, Chongqing, Suzhou, Shijiazhuang and Wuhan were the ten cities with greatest CO2 emissions in 2005, with total CO2 emissions of 205, 184, 145, 126, 116, 103, 96, 93, 90 and 81 Mt, respectively. These cities were either megacities or those dominated by coal, iron or steel production. However, the three cities with the highest CO2 emissions per GDP and CO2 emissions per capita were Jiayuguan, Wuhai and Shizuishan, which were dominated by industry, small- or medium-sized, and exhibited a high demand for heat and cooling. Cluster analysis revealed that industrial energy consumption was the dominant emission source for most cities, except Haikou and Lhasa, for which indirect CO2 emissions were dominant. This study will greatly contribute to the city level CO2 emission inventory and research on China.

Measuring the acoustic pressure in an acoustic standing wave field is essential as a means to study acoustic levitation and other related techniques. In this work it was shown that the pressure of an acoustic standing wave field could be measured on line, in a non-contact way, using a scanning Laser Doppler Vibrometer (LDV), where the LDV output is proportional to the integral of the acoustic pressure over the laser path. In the method used to measure acoustic pressure, first, the LDV outputs, $\upsilon _{sLDV}$ and $\upsilon _{eLDV}$ , are obtained by using both COMSOL-MATLAB-based (CM) co-simulation and through experimental measurements. Next, the acoustic pressure distribution is obtained using a MATLAB-based programme and this is reconstructed by using $\upsilon _{sLDV}$ and $\upsilon _{eLDV}$ , based on the Hankel-Fourier (HF) algorithm. Further, the acoustic pressure measurements obtained by using these two methods are cross compared, in that way to demonstrate the effectiveness of the method presented.

China's demand for crop products is increasing, leading to a great deal of consumption of local resources and industrial inputs such as agricultural machineries, chemical fertilizers, pesticides and energies. Many environmental problems also occurred, such as water pollution, soil erosion and contamination, and CO2 emissions. Therefore, it is imperative to assess crop production's sustainability and identify the key driving forces of its rapid development so that the proper mitigation policies can be proposed. An emergy analysis method was employed due to its advantage of linking economic development with natural ecosystem service. Emergy sustainability index was chosen as the key indicator to measure crop production performances in 31 Chinese provinces for the period 2006–2015. The results demonstrate that the EYRs in 31 Chinese provinces are entirely keeping around 1 and the maximum and minimum values of ELR are respectively 1.71 in Guizhou and 8.29 in Tibet. Under this circumstance, the mean ESI values in 30 Chinese provinces are all less than 1, except Guizhou. This indicates that most Chinese provinces will have to improve their crop production toward sustainable agricultural development. Then, a logarithmic Mean Divisia Index (LMDI) decomposition method was applied to identify the key driving forces that affect the evolution of ESI. The change of ESI (ΔESI) was decomposed into five factors: Scale and intensity factor (I), which depends on emergy density; Non-renewable resources factor (T), which depends on the density of non-renewable resources emergy; Productivity of labor factor (P), which depends on the productivity of labor; Renewable resources factor (E), which depends on intensity of renewable resources and number of Labor (G), which depends on labor inputs. The decomposition analysis results indicate that labor and renewable resources are the major factors affecting China's sustainable crop production, while other factors also have certain impacts. Such findings can provide valuable policy insights so that more appropriate crop production policies can be prepared by considering the local realities.

In China, rapid development of electric vehicles resulted in large consumption of lead and lead products such as lead acid batteries (LABs). Recycling LABs is one option to mitigate natural resource depletion and corresponding environmental issues. However, few studies have been conducted to measure the operation of LABs recycling industry. Consequently, it is necessary to initiate such a study so that key barriers on promoting this industry can be identified. Under such a circumstance, this study proposes an emergy-based evaluation framework to evaluate one LABs recycling firm in Yunnan so that the emissions’ impact on human health and ecosystem from this firm can be quantified. A set of emergy-based indicators are established to evaluate the sustainability of this recycling firm. The results show that the investigated system had a higher emergy efficiency compared with that primary ore exploitation system. However, the extremely low values of emergy indicators indicate that this recycling system could not achieve sustainable development goals due to its heavy dependence on nonrenewable resources. Based upon such results and local realities, policy suggestions are raised in order to improve the overall sustainability of such a recycling system.

Overcapacity is regarded as an inevitable problem for rapid economic developing countries like China, which also causes serious adverse impacts on the environment and public health. However, few studies have quantified the overcapacity feature and corresponding co-benefit from de-capacity policy. To fill such research gaps, this study constructed a comprehensive assessment model by combining the Data Envelopment Analysis (DEA) model, the GAINS-China (Greenhouse gas - Air pollution Interactions and Synergies) model, and a meta-analysis and health impact assessment module, to measure the capacity utilization rate of 41 industrial sectors in 31 Chinese provinces and forecast the environmental and health co-benefits from de-capacity policy in 2050. Results showed that the capacity utilization rate of China's industry is 64.13% in 2018, which is much lower than the threshold value of 75%, indicating serious overcapacity in China's industry. Capacity utilization rates of light industries are higher (around 70%) than heavy industries (50%-60%), and the capacity utilization rate in East and South-Central China is higher (70%-96%) than West China (below 40%). Under a de-capacity scenario in 2050, China's CO

Differentiated empowering leadership is common in organizations; however, its effect on employee proactive customer service performance remains less understood. Drawing on social comparison theory, this study proposes a multilevel model for how and when differentiated empowering leadership affects employee proactive customer service performance. The study, based on a sample of 228 employees from 77 teams in China, shows a negative relationship between differentiated empowering leadership and employee proactive customer service performance through employee organization-based self-esteem. This indirect relationship is moderated by empowering leadership and employee prosocial motivation. Specifically, the influence of differentiated empowering leadership on employee organization-based self-esteem is more negative when employees receive low empowering leadership, and the relationship between employee organization-based self-esteem and proactive customer service performance is more positive for employees with high prosocial motivation. These findings extend previous knowledge on differentiated empowering leadership and provide practical insights for hotel managers.

With fast development and urbanization, Chinese cities are facing several challenges including issues of environmental pollution, climate change, resource depletion and landfills shortage. Waste recycling is one effective way to respond these challenges. Under such a situation, this paper aims to evaluate energy saving and carbon reduction potential of recycling wastes by taking Shanghai, the biggest city in China, as a case study. Results show that 8.7 Mt standard coal (tce) and 16.81 Mt CO2 could be reduced under current recycling system in Shanghai. And recycling of waste steel and nonferrous metals were the two dominant contributors, accounting for about 44% and 42% of energy saving, and 60% and 33% of CO2 reduction, respectively. If the recycling rates of main recyclable wastes were improved to 100%, additional 6.44 Mt energy and 10.02 Mt CO2 could be further saved, mainly from recycling waste glass, waste plastic and waste metals. Adoption of RPF (Refuse Plastic & paper Fuel) could further contribute to 1.24 Mt energy saving and 2.67 Mt CO2 reduction. Finally, policy implications on establishing a mature recycling system and promoting RPF technologies are discussed, in which the potential on reducing total energy consumption and CO2 emission of Shanghai can reach 6.6% and 4.9%, respectively.

The expansion of renewable energy sources for electricity generation is an important part of China's energy strategy to reduce the dominance of coal generated power. Different energy systems face unique challenges with their different energy structures and economic context, which make it necessary to identify the roadmap for renewable energy development with consideration of local energy system. Our study aims to fill a research gap by identifying the penetration of renewable energy in China's energy system. The study begins with a brief review of the current state of renewable energies in China and then identifies the effect of large penetration of wind power and solar energy. China's energy system is simulated using the EnergyPLAN model and assessed under different penetration points of renewable energy sources from technical and economic perspectives. Different realistic intervals of penetration are discussed. Finally, our analysis identifies that the maximum realistic penetration of wind power and solar energy are respectively 38% and 27%.

As a means of converting waste to energy, improvement of energy recovery efficiency from municipal solid waste (MSW) has taken on great importance and necessity. Previous studies have focused on the waste-to-energy potential from the viewpoints of technology, such as waste power generation (WPG); however, there is large room for improvement in WPG efficiency. Moreover, with reduction in population in some developed countries, the potential for further improvement of energy recovery from waste needs to be investigated, considering both geographical characteristics and future trends. To fill this research gap, this study proposes four efficient MSW management options through integrating MSW management and an urban symbiosis network. The Tokyo Metropolis, Japan, was selected as a case study, and the costs and benefits, effects of greenhouse gas (GHG) emission reduction, and energy recovery efficiency of each option were quantitatively analyzed. The results showed that Option 4 (urban symbiosis without source separation) has the highest energy recovery efficiency (65.95%), followed by Option 3 (urban symbiosis with source separation) and Option 2 (MSW centralized treatment) in 2030. Compared with Option 1 (business as usual), Option 3 will slightly increase the total cost, while Option 4 is the most profitable option, and the benefit will rise to 1.81 × 1010 JPY in 2030. Reduction of greenhouse gas (GHG) emissions by 2030 will be greatest with Option 3, which will eliminate 9.44 × 105 tonnes of CO2e emissions. Also by 2030, Option 4 and Option 2 will reduce the CO2e emissions by 6.58 × 105 tonnes and 2.27 × 105 tonnes, respectively. To promote the transition to a low carbon city, Tokyo must improve the energy recovery efficiency of MSW and use more renewable and recycled energy resources to substitute for fossil fuels. This study provides a practical guide for establishing a more efficient MSW management system toward the goal of a low carbon society.

Many industrial parks are implementing industrial symbiosis in order to move toward eco-industrial parks. Research methods on industrial symbiosis expand from focusing on material flows and economic benefits to addressing on social aspects since collaboration among different firms can determine the efficiency of industrial symbiosis. Under such a circumstance, this study focuses on investigating industrial symbiosis relationships among tenant firms within one mining industrial park. Social network analysis (SNA) method was selected for analyzing the characteristics, power quantification and structure of the industrial symbiosis network by taking Gujiao mining industrial park as a case study. Results show that industrial symbiosis is still in its infancy in Gujiao industrial park and should be further optimized. Those anchor firms have less influence on industrial symbiosis and should be encouraged to actively involve in industrial symbiosis. Finally, policy recommendations are proposed by considering the local realities, including the establishment of an information platform, the use of economic instruments, necessary research and development efforts and broad public participation.

Gold production has significant environmental impacts on ecosystem and human health. China, as the largest gold production country in the world, deserves a special attention. This study assesses the environmental impacts of gold production in China by using life cycle assessment. Key factors contributing to the total environmental burden of gold production were also identified. In addition, uncertainty analysis based on Monte Carlo was conducted to improve the reliability of results obtained in this study. Results show that impact from metal depletion category mainly from gold ore mining was the most contributor to the total environmental impact. Meanwhile, impacts from climate change, terrestrial acidification, human toxicity, particulate matter formation, marine ecotoxicity, and fossil depletion also made contributions. The overall environmental impact was dominated by key factors such as ore mining, energy consumption, and on-site emissions. Policy suggestions (e.g., maximizing resource efficiency, adjusting energy structure, promoting gold recycling, implementing ecological compensation) were proposed to promote the sustainable development of gold production.

Flexible electrochromic energy storage (EES) systems have attracted tremendous attention because of their combined advantages of color-changing and energy-storing. Although copper nanowires (Cu NWs) flexible transparent electrodes (FTEs) have been considered as one of the most promising candidates for next-generation flexible electronics, its instinct electrochemical instability hindered its application in flexible electrochemical energy system, including EES device. Herein, we proposed a highly conductive electrochemically stable FTE based on Cu-Au alloy NWs network synthesized in a facile and simple electrochemical method. Compared with the pristine Cu NWs network that breaks into disconnected nanorods less than 10 s in 1 M H2SO4 solution during electrochemical anodic corrosion, the Cu-Au NWs network remained stable after 4000 s under the same condition. Furthermore, thanks to the forming of firm joints between the stacked NWs during inducting Au atoms, the optical-electrical performance (a sheet resistance of 23.2 Ohm/sq at a transmittance of 87%) and mechanical flexibility were highly improved. Based on these improvements, anodic PANI and cathodic WO3 layer were successfully deposited onto the Cu-Au NWs FTE by electrochemical method. An asymmetric-EES (AEES) device was assembled utilizing these complementary electrodes, which concurrently exhibited excellent electrochromic (coloration efficiency: 153.77 cm2/C at 633 nm) and energy storage performance (areal capacitance: 2.29 mF/cm2), demonstrating their potential for smart multifunctional flexible electronics.

This paper aims to solve the motion control problem of the load side of the series elastic actuator (SEA), whose complete dynamical model is a fourth-order system suffering from the matched and mismatched uncertainties. A partial-state feedback based dynamic surface controller is developed for SEAs by combining a filter-based observer. The observer is responsible for estimating the two velocity states, the matched and mismatched uncertainties; the dynamic surface technique is utilized to avoid the “explosion of terms” appearing in the conventional backstepping method. The overall control framework only needs position-states feedback. The rigorous stability analysis is provided in the case that only the state-independent uncertainties are assumed to be bounded in advance. And the semiglobal boundedness of tracking error is guaranteed. Experimental tests are conducted to verify the effectiveness of the proposed control framework.

Recovering the landfill gas from municipal solid wastes for power generation is one feasible approach to respond both climate change and resource depletion issues. Under such a circumstance, it is important to evaluate the overall performance of its production process. This study proposes an integrated evaluation method by integrating emergy analysis and eco-indicator 99 method. Key impact factors influencing the sustainability are uncovered by adopting Kaya identity and index decomposition analysis (IDA). One MSW treatment plant in Yunnan province of China was selected as one case study site. The results indicate that the overall performance of the MSW treatment plant has been improved after operating a power generation system. The emissions' impact has been reduced by 56.85% and 2.44gCO2eq has been offset when generating 109sej of electricity. However, the low economic benefit, the increase of nonrenewable empower density and the low investment effectiveness are still key factors that hinder its sustainability. In order to address these issues, several suggestions are raised by considering the local realities.

Both air pollutant and carbon emissions are serious problems in China, particularly the economic and pollution intensive urban agglomerations. Therefore, this paper selected the most severely polluted Jing-Jin-Ji region (Beijing, Tianjin and Hebei urban clusters) to study the potential of mitigating both carbon and air pollutant emission. The Computable General Equilibrium (CGE) model was applied and six scenarios were constructed by considering policies of environmental tax and renewable energy. Business-as-usual (BaU) scenario assumed no tax and fixed renewable energy to 2002 level, whereas other scenarios assumed that intensified renewable energy (RE) and tax on sulfur dioxide (SO2) (TAX1 and TAX2) were implemented either alone or combined. The results indicated that both RE and SO2 tax could contribute to regional low-carbon development and air pollutant reduction, and the reduction is about 10–40% depending on scenarios. However, Renewable energy is always more effective in reducing CO2 and air pollutant emissions than TAX1 but less effective than TAX2 for Hebei. From the sectoral perspective, power sector would exhibit both the largest emissions and reduction potentials in all three Cities, accounting for about 21%, 31% and 28% of total CO2 emissions respectively for Beijing, Tianjin and Hebei, in 2020. Considering different policies, it is more effective for Hebei to apply renewable energy to reduce its power sector emissions in the long term, and tax policy is more effective for emission reduction from other sectors in Tianjin. Further analysis on the economic impact of mitigation policy revealed that Tianjin and Beijing would suffer relatively greater negative impacts than Hebei in terms of loss in total GDP, while developing renewable energy could help to reduce such negative impacts. It is suggested that the policymakers need to take into accounts the regional economic situation and natural resource potential when they formulate low-carbon policies.

With fast development, it is not easy for China to achieve carbon reduction targets only by traditional command and control measures (e.g., the measures for energy-efficiency). Carbon tax is advocated as one effective complementary measure and has high possibility to be implemented for China’s future low carbon development. Under such a circumstance, this paper aims at forecasting the possible impact of carbon tax on both carbon reduction and economic loss of 30 Chinese provinces. A 30-Chinese-province CGE (Computational general equilibrium) model has been developed to conduct the provincial evaluation, and seven scenarios including Business-as-Usual (BaU) scenario and six carbon tax scenarios with carbon price from 20 USD/ton to 120 USD/ton up to 2030 are set. The results show that China’s industrial CO2 will be reduced from 12.2 billion tons under BaU scenario to 10.4 billion tons, 9.3 billion tons, 8.5 billion tons, 7.9 billion tons, 7.4 billion tons and 7.0 billion tons under scenarios of TAX20, TAX40, TAX60, TAX80, TAX100 and TAX120 in 2030, respectively. Electricity, Metal and Chemicals sectors have high reduction potentials and are priority sectors for carbon tax policy. Provincial disparity analysis demonstrates that coal production/consumption and total energy consumption are key factors to affect carbon tax effect on CO2 reduction, and Inner Mongolia, Shandong, Shanxi and Hebei have the largest industrial CO2 reduction potentials after levying carbon tax. However, the implementation of carbon tax will impede economic development for all provinces. Therefore, the concept of carbon tax efficiency is further proposed in order to evaluate the effectiveness of carbon tax by considering both CO2 reduction and GDP loss. Policy suggestions indicate that provinces of Shanxi, Inner Mongolia, Hebei and Anhui should be set priority when implementing carbon tax policy in China, and carbon price should be no more than 50 USD/ton.

Industrial structure adjustment is one solution for responding economic slowdown and environmental problems occurred during China’s rapid industrialization. Such an adjustment may also lead to carbon emission reduction since it encourages industrial innovation and resource efficiency. However, few studies have been conducted on examining the effect of industrial structure adjustment on carbon emission reduction. Under such a circumstance, this study develops an integrated evaluation model based on Input-Output Analysis and Social Network Analysis to quantify the evolutionary trends of industrial structure, demonstrate the inner-relationship between different sectors and investigate the industrial structure-related carbon emissions. China and Japan were selected as case study countries. Results show that industrial structure was gradually improved in China and various connections were established between different sectors. For Japan, the industrial network densities were lower than for China and exhibited a downward trend that reflected the weakened relationship between different industries. Service sectors dominated the Japanese economy, as shown by the relatively higher degree centrality and betweenness centrality of service sectors. The electricity and heat production sector was further investigated to illustrate the industrial structure-related carbon emissions. Finally, this study concluded that compared to the industrial structure features in a developed country, such as Japan, China’s industrialization is still in its infancy. Thus, it is crucial to prepare industrial structure adjust policies so that the overall social-economic performance can be improved.

The disparity between import and export prices of China's graphite products indicates that China suffers a heavy loss of graphite resources. China's graphite resource abundance doesn't transform into an economic advantage. This paper tries to promote sustainable use of China's graphite resources by investigating the effect of environmental regulations on China's graphite resource export. Based on the gravity model and the panel data of the top 30 countries that imported graphite resources from China during 2005–2014, economical mass, population, graphite export price, export duty refund (EDR), language, recession and political conflicts are selected as measurable indicators of environmental regulations to study how the corresponding changes affect graphite export values. The results demonstrate that the determinants of China's graphite export values include economical mass, export price, export duty refund, and language. Policy recommendations are then raised in order to improve sustainable development of China's graphite industry.

One proposed strategy to solve current environmental challenges is industrial and urban symbiosis (I/UrS); however, appropriate evaluation methods are needed so that the potential benefits of I/UrS can be quantified. Several evaluation methods have been applied separately to study I/UrS, but no integrated studies have been conducted by applying different methods in the same case study area. Therefore, this study aimed to establish a comprehensive framework to evaluate I/UrS by combining the material flow analysis (MFA), carbon footprint (CF) and emergy methods. First, we developed a unified database and step-by-step process to clarify the waste distribution and recycling processes in an industrial city. Then a baseline scenario and an I/UrS scenario were set up to define the baselines and effects of I/UrS and compare the results. Finally, the three methods were applied to identify physical features in the I/UrS system. The MFA-based results showed that the use of I/UrS led to a 6.4% reduction in the physical value of material use. The CF-based results indicated that reduction of waste and by-products results in a 13.8% reduction in CO 2 e emissions. The emergy-based results showed that, with the implementation of I/UrS, the value of the emergy sustainability index (excluding labor and services) improved greatly (a 49.2% emergy reduction) as compared with the baseline case (a 14.3% reduction). In addition, the effects of implementing I/UrS by waste and by-product exchanges for blast furnace slag, scrap steel, waste paper, and waste plastic were evaluated. Whereas the CF reductions of unit ton of blast furnace slag is relatively low, emergy reductions of that is comparatively high. If policymakers only consider CF results when addressing the issue of climate change, the effects on emergy will be underestimated in this case. We conclude that the main actors in this area release huge emissions, but they also have a high potential to reduce their environmental loads. In addition, with appropriate designs, waste paper and plastics recycling could be highly efficient. Finally, the integration of the three evaluation methods should contribute to creating a low carbon and more resource independent society.

Incineration has been regarded as a promising method to respond to municipal solid waste (MSW) challenges. However, its high cost and health impacts are the main barriers to the development of incineration. This study aims to investigate the cost-benefit of MSW incineration in 31 Chinese provinces to identify the regional disparity of incineration policy in China. Life cycle environmental impacts and costs were analyzed using the life cycle assessment software Gabi 8.0 and method CML-2001. Results show that MSW disposal costs, Global Warming Potential (GWP) and Eutrophication Potential (EP) will decline significantly with the increase in incineration rate for all Chinese provinces, while the environmental impacts of Human Toxicity Potential (HTP), Ozone Layer Depletion Potential (OLDP) and Terrestric Ecotoxicity Potential (TETP) increase the trend. Economically developed and populated provinces such as Guangdong, Jiangsu, Zhejiang and Shandong have both a higher incineration volume and incineration potential. As for the cost-benefit analysis, developed provinces such as Guangdong, Chongqing, Shanghai and Tianjin exhibit the highest cost-benefit in toxic impacts of HTP, TETP and ODP. Northern provinces such as Jilin, Xinjiang, Heilongjiang and Hebei have the lowest cost-benefit in toxic impacts but have the highest cost-benefit in GWP and EP. Finally, policy remarks on incineration cost, priority provinces, integration of sorting and incineration are also discussed.

A sonochemical reactor was developed to study the ultrasound-assisted cyanide extraction of gold from gold ore at low temperature. The effects of ultrasound on gold leaching in low temperature and conventional conditions were investigated. At the low temperature of 10 °C, ultrasound-assisted extraction increased extraction rate of gold by 0.6%–0.8% and reduced the gold content of cyanide tailings to 0.28 g/t in the leaching of gold concentrate and cyanide tailings, respectively. At the conventional temperature of 25 °C, ultrasound-assisted extraction obtained a 0.1% higher extraction rate of gold compared with conventional extraction, with the unit consumption of NaCN reduction of 15%. The analysis of kinetic model also demonstrated that sonication indeed improved the reaction of gold leaching greatly. The mineralogy and morphology of ore were further analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) and particle size analyzer to explore the strengthening mechanism of gold leaching. The results showed that the ore particles were smashed, the ore particle surface was peeled, the passive film was destroyed and the reaction resistance decreased under ultrasonic processing. Therefore, the extraction rate of gold was improved and the extraction time was shortened significantly in ultrasound-assisted cyanide extraction.

The grey water footprint (GWF) can be used to connect wastewater quality and quantity, making it a powerful tool for policy makers and those responsible for managing wastewater systems. As a supplementary to existing GWF research, this study explores the GWF evolution of eight economic regions in China by taking into consideration the GWF of livestock feeding. In addition, we use the logarithmic mean division index method to study the background driving forces of GWF in primary industry for eight economic regions. Results show that the overall GWF in China fluctuates from 6082 billion m3 to 6238 billion m3 between the years 2003 and 2015. Primary industry contributes most to the GWF because of livestock feeding, particularly for the northwest economic region, accounting for 84.81% in 2015. The southwest economic region has the highest total GWF, and east coast region has the lowest total GWF. An analysis of driving forces shows that economic scale and industrial structure are the driving forces that best explain the GWF for the East coast, middle of Yellow River, Northwest, and Southwest economic regions. The effects of economic scale and pollution producing intensity are driving the GWF in the Northeast Regions. For the North coast and middle Yangtze River Regions, economic scale, industrial structure, and pollution producing intensity are driving forces for GWF. While for the South coast region, population is an important contributor apart from economic scale and industrial structure. Policy implications from perspective of the agriculture GWF and endowment of different regions were finally discussed.

The establishment of recycling network is critical to improve municipal solid waste (MSW) management. However, how to determine the best locations for the recycling stations and recycling centers remains to be solved. Under such a circumstance, this study aims to forecast the MSW generation and develop a cost-based location optimization model using p-median method so that the optimal scale and location of recycling centers can be identified. Shanghai, with an ambitious plan for promoting MSW recycling at the city level, was selected as a case study city. Results show that Shanghai’s MSW generation rate will be about 3% from 2017 to 2020. Regional distribution analysis shows that the downtown areas have higher intensity for MSW generation due to high population density and consumption level. Fourteen regional recycling centers were identified to be the optimal places for establishing recycling centers. The achievement of this scenario can lead to the lowest total cost of 144 million Chinese Yuan. Moreover, the optimal results may change if unit transportation cost and unit scale cost are changed. For instance, the optimal numbers of recycling centers will increase with the increase of unit transportation cost or decrease of unit scale cost. Finally, model limitations and policy recommendations are raised by considering the local realities.

The investigation on photoferroelectrics regained attention these years as their potential in various applications. In this work, BiAlO3/La0.67Sr0.33MnO3 (BAO/LSMO) heterostructure was deposited on SrTiO3 (STO) substrate with pulse laser deposition method. An abnormal region around 240 K on temperature dependent permittivity is ascribed to phase transition of BAO/LSMO heterostructure. Significant reduction (maximum variation of −32.6%) in dielectric permittivity upon ultraviolet light illumination (intensity of about 0.5 W/cm2) can be attributed to redistribution of built-in electric field in BAO/LSMO interface. The positive magnetodielectricity (maximum variation of 17.2%) stems from negative magnetic resistance and magnetostriction of LSMO. Furthermore, magnetic field significantly modified photodielectricity, exhibiting multifield coupling effect on the BAO/LSMO heterostructure, revealing its potential use for advanced magneto-optoelectronic devices.

Having a continuous mode of transportation, in the manufacturing and pharmaceutical industries, is desirable and this facilitated by the usage of dual transducer-type ultrasonic levitation-based transportation systems. It is well known that the structural and electrical parameters determine what can be transported continuously, but the relationships between these important parameters are still not clear. In this study, the vibrating plate length and the phase shift between the two transducers were investigated as both of these are key parameters for the transportation system, and affect the standing wave ratios (SWRs), the acoustic radiation forces, and consequently the way the transportation system operates. Through numerical analysis and experimental verification, it can be seen that when the sum or difference of the spatial phase difference (determined by the vibrating plate length) and the phase shift is equal to 180° × (1 + 2n) (where n is an integer), except for the spatial phase difference of 180°·m (where m is also an integer) and the SWRs approaches unity, all this implying that traveling waves (TWs) are dominantly excited on the vibrating plate. As a consequence, the TW-induced acoustic radiation force, which greatly exceeds the standing wave-induced force, causes the continuous transportation of the particle being moved in the sound field. This paper not only clarifies the requirements for generating this continuous transportation, but also provides valuable information on the practical design of such a transportation system.

Greywater is found to bring higher water pressure than freshwater consumption, thus grey water footprint (GWF) has received great attention as a comprehensive indicator to assess wastewater pollution. Industrial park is an important source for wastewater discharge, but few GWF studies have been conducted at the industrial park level due to lack of data availability. To fill such a gap, this study develops one GWF assessment model at the industrial park level by considering wastewater sources from enterprises, wastewater treatment plant (WWTP), residents and agriculture. Such a model is then tested in the Changzhou Economic and Technology Development Zone (CETDZ). Results show that non-connected enterprises were the dominant sources for wastewater discharge, particularly in terms of total phosphorus (TP) and NH3–N pollution. The critical pollutants for GWF in CETDZ include total nitrogen and TP, which are mainly from rural towns. The top ten companies for GWF are identified, which can help the local government to prepare more appropriate wastewater control policies. Several mitigation measures, including increasing connection rate of the non-connected enterprises, controlling key enterprises, recycling wastewater from WWTP, and reducing the background concentration of natural water bodies, are investigated, in which increasing connection rate is identified as the most effective one. Finally, several policy recommendations on increasing connection rate, such as implementing river dredging projects and artificial wetland technology, are proposed.

Sustainable crop production is a significant challenge in China. To achieve this goal, it is necessary to evaluate environmental impacts related to the sustainable development of crop production by integrating scientific and practical indicators. Therefore, this study employed emergy and index decomposition analysis approaches to assess the environmental impacts of non-point source pollution and the overall performance of crop production in China’s 31 provinces. First, the emergy flow of emission impacts and two new indicators, the emergy sustainability index and the emergy-based pollutant-producing coefficient, were proposed to comprehensively measure crop production performance from 2012 to 2015. The results demonstrated that the environmental impacts of non-point source pollution (EIN) were predominantly attributed to total nitrogen and phosphorus contents and mulching film residuals, which substantially increased the total emergy used and reduced the sustainability of crop production in each province. The ratio of EIN plus purchased resources (F) to total emergy used (U) were consistently greater than 80% in all 31 provinces, while the ratio of local resources including the emergy of local renewable (R) and non-renewable resources (N) to the total emergy was relatively small, accounting for less than 20% in all provinces. Then, a logarithmic mean Divisia index decomposition method was applied to identify the key driving forces influencing the evolution of EIN. The decomposition analysis indicated that the economy factor had a major promoting effect on EIN growth in all provinces except Beijing and Shanghai. Intensity and technology factors had a limiting effect on EIN growth. These findings provide valuable insights for developing appropriate crop production policies that consider local conditions.

China is experiencing rapid development and suffering from resource depletion and increasing environmental emissions. It is necessary to identify the key patterns of resource use in different Chinese regions so that more appropriate solutions can be raised. Under such a circumstance, the aim of this paper is to scientifically measure and evaluate the sustainability of natural resources utilization of 30 Chinese provinces for the year of 2007 by adopting a bio-perspective method-emergy analysis. After referring to the traditional emergy accounting method, several emergy-based indicators were established to evaluate resource flows, structure, efficiency and the overall sustainable level of different Chinese regions. Furthermore, by employing GIS technology, spatial distribution of natural resources was presented to illustrate emergy consumption with various regional characteristics in 30 Chinese provinces, which may help better understand regional disparities of resource utilization. The results show that regions with most emergy consumption include Shanxi (2.07E+24sej) and Shandong (2.07E+24sej), and most regions with higher resource consumption locate in east China, while less developed region Qinghai has the highest sustainability level, with ESI being 44.82. Another key finding is that renewable resources were very important to sustainability development, and a large amount of consumption on non-renewable resources led to higher environmental press on local and surrounding ecosystems. Sustainable resource use can only be achieved by reducing total resource use, encouraging technology innovation, initiating institutional reform and preparing region-specific development strategies.

This study evaluates the PM2.5 pollution-related health impacts on the national and provincial economy of China using a computable general equilibrium (CGE) model and the latest nonlinear exposure-response functions. Results show that the health and economic impacts may be substantial in provinces with a high PM2.5 concentration. In the WoPol scenario without PM2.5 pollution control policy, we estimate that China experiences a 2.00% GDP loss and 25.2 billion USD in health expenditure from PM2.5 pollution in 2030. In contrast, with control policy in the WPol scenario, a control investment of 101.8 billion USD (0.79% of GDP) and a gain of 1.17% of China's GDP from improving PM2.5 pollution are projected. At the provincial level, GDP loss in 2030 in the WoPol scenario is high in Tianjin (3.08%), Shanghai (2.98%), Henan (2.32%), Beijing (2.75%), and Hebei (2.60%) and the top five provinces with the highest additional health expenditure are Henan, Sichuan, Shandong, Hebei, and Jiangsu. Controlling PM2.5 pollution could bring positive benefits in two-thirds of provinces. Tianjin, Shanghai, Beijing, Henan, Jiangsu, and Hebei experience most benefits from PM2.5 pollution control as a result of a higher PM2.5 pollution and dense population distribution. Conversely, the control investment is higher than GDP gain in some underdeveloped provinces, such as Ningxia, Guizhou, Shanxi, Gansu, and Yunnan.

With the rapid growth of aluminum production, reducing greenhouse gas (GHG) emissions in China’s aluminum industry (CAI) is posing a significant challenge. In this study, the energy-related GHG emission trajectories, features and driving forces of CAI are analyzed from the perspective of life cycle analysis (LCA) from 2004 to 2013. Results indicate that CAI experienced a rapid growth of energy-related GHG emissions with an average annual growth of 28.5 million tons CO2e from 2004 to 2013. Energy-scale effect is the main driving force for energy-related GHG emissions increase in CAI, while emission-factor effect of secondary aluminum production plays a marginal effect. Construction and transportation-related activities account for the bulk of the embodied emissions, accounting for more than 40% of the total embodied emissions from CAI. Policy implications for GHG mitigation within the CAI, such as developing secondary aluminum industry, improving energy mix and optimizing resource efficiency of production, are raised.

Xinjiang Uygur Autonomous Region was selected for studying its energy-related greenhouse gas emission features due to its rich reserve of coal, crude oil and natural gas. First, GHG inventories in Xinjiang were presented in order to provide a holistic picture of its features and trajectories on energy-related GHG emission. Then, transferred GHG emission embodied in exported energy products was analyzed. Finally, the driving forces for energy-related GHG emission increment were uncovered by adopting a time series LMDI analysis. Results indicate that annual energy-related GHG emission increased stably after 2002 and reached 227.71 Mt CO 2 e in 2011. Fugitive GHG emission was an important contributor to Xinjiang׳s GHG emission, accounting for more than 8% of the total energy-related GHG emission in 2011. Transferred GHG emission embodied in exported energy products was up to 8.07 Mt CO 2 e in 2011, accounting for 3.54% of the total energy related GHG emission, indicating a shift of environmental pollution from other regions to Xinjiang. Decomposition analysis shows that economic activity effect was the key driving force for energy-related GHG emission increment in Xinjiang during 1995–2011 and intensity effect partially offset the energy-related GHG emission growth. Research findings propose that a comprehensive consideration on all the relevant aspects should be initiated so that appropriate mitigation policies can be raised by considering the local realities.