To deal with a polluted by-product of coal production,central China’s Shanxi Province has explored a governance path that addresses both the symptoms and root causes.
The electromagnetic wave absorption of silicon carbide nanowires is improved by their uniform and diverse cross-structures.This study introduces a sustainable and high value-added method for synthesizing silicon carbi...The electromagnetic wave absorption of silicon carbide nanowires is improved by their uniform and diverse cross-structures.This study introduces a sustainable and high value-added method for synthesizing silicon carbide nanowires using lignite and waste silicon powder as raw materials through carbothermal reduction.The staggered structure of nanowires promotes the creation of interfacial polarization,impedance matching,and multiple loss mechanisms,leading to enhanced electromagnetic absorption performance.The silicon carbide nanowires demonstrate outstanding electromagnetic absorption capabilities with the minimum reflection loss of-48.09 d B at10.08 GHz and an effective absorption bandwidth(the reflection loss less than-10 d B)ranging from 8.54 to 16.68 GHz with a thickness of 2.17 mm.This research presents an innovative approach for utilizing solid waste in an environmentally friendly manner to produce broadband silicon carbide composite absorbers.展开更多
Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may po...Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may pose certain environmental risks.Snow-melting agents and snow samples were collected and analyzed from highways,arterial roads,footbridges,and other locations in Beijing after the snowstorm in December 2023.It was found that the main component of snow-melting agents was sodium chloride with high concentrations of Cu,Mn,and Zn,which are not regulated in the current policies,despite the recent promotion of environmentally friendly snow-melting agents.The Pb,Zn and Cr contents of some snow samples exceeded the limitation value of surface water quality standards,potentially affecting the soil and water environment near roadsides,although the snow-melting agents comply with relevant standards,which indicates the policy gap in the management of recycled industrial salts.We reviewed and analyzed the relevant standards for snow-melting agents and industrial waste salts proposed nationally and internationally over the past 30 years.Through comparative analysis,we proposed relevant policy recommendations to the existing quality standards of snow-melting agents and the management regulations of industrial waste salts,and the formulation of corresponding usage strategies,aimed at reducing the potential environmental release of heavy metals from the use of snow-melting agents,thereby promoting more sustainable green urban development and environmentally sound waste management.展开更多
In order to address the synergistic optimization of energy efficiency improvement in the waste incineration power plant(WIPP)and renewable energy accommodation,an electricity-hydrogen-waste multi-energy system integra...In order to address the synergistic optimization of energy efficiency improvement in the waste incineration power plant(WIPP)and renewable energy accommodation,an electricity-hydrogen-waste multi-energy system integrated with phase change material(PCM)thermal storage is proposed.First,a thermal energy management framework is constructed,combining PCM thermal storage with the alkaline electrolyzer(AE)waste heat recovery and the heat pump(HP),while establishing a PCM-driven waste drying system to enhance the efficiency of waste incineration power generation.Next,a flue gas treatment method based on purification-separation-storage coordination is adopted,achieving spatiotemporal decoupling between waste incineration and flue gas treatment.Subsequently,a two-stage optimal dispatching strategy for the multi-energy system is developed:the first stage establishes a dayahead economic dispatch model with the objective of minimizing net system costs,while the second stage introduces model predictive control(MPC)to realize intraday rolling optimization.Finally,The optimal dispatching strategies under different scenarios are obtained using the Gurobi solver,followed by a comparative analysis of the optimized operational outcomes.Simulation results demonstrate that the proposed system optimizes the output and operational states of each unit,simultaneously reducing carbon trading costs while increasing electricity sales revenue.The proposed scheduling strategy demonstrates effective grid peak-shaving functionality,thereby simultaneously improving the system’s economic performance and operational flexibility while providing an innovative technical pathway for municipal solid waste(MSW)resource utilization and low-carbon transformation of energy systems.展开更多
A study recently published in Scientific Reports shows that fibers from agricultural waste can make 3D-printed concrete stronger and more environmen-tally friendly.This approach not only gives new life to organic wast...A study recently published in Scientific Reports shows that fibers from agricultural waste can make 3D-printed concrete stronger and more environmen-tally friendly.This approach not only gives new life to organic waste but also helps address the environmental issues linked to traditional building materials.The research found that adding natural fibers improves both the strength and the printability of concrete,offering a more efficient and eco-friendly option for modern construction.展开更多
Jerada coal mining generates extensive coal mine waste rock(CMWR)piles rich in valuable minerals,posing environmental challenges and economic opportunities.This study examines reprocessing feasibility through 3D geome...Jerada coal mining generates extensive coal mine waste rock(CMWR)piles rich in valuable minerals,posing environmental challenges and economic opportunities.This study examines reprocessing feasibility through 3D geometallurgical characterization.Sampling used down the hole hammer drilling technique(DTH)and drone surveys for topographical precision.Over 620 samples from(T01,T02,T08)underwent comprehensive analyses including particle size distribution,x-ray fluorescence(XRF),total sulfur/carbon analysis(S/C),and inductively coupled plasma mass spectrometry(ICP-MS)for physical-chemical characterization.Mineralogical aspects were explored via optical microscopy(OM),X-ray diffraction(XRD),scanning electron microscopy(SEM),electron probe microanalysis(EPMA),and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS).Quantitative mineral evaluation by scanning electron microscope(QEMSCAN)provided mineral insights.Chemical data was used in a 3D block model to quantify residual coal.Results for the three examined CMWR piles(T01,T02,and T08)showed varying D80 from 160 to 300μm,notable carbon content averaged 12.5 wt%(T01),16 wt%(T02),and 8.5 wt%(T08).Sulfur presence exceeded 1 wt%in T08,and potential environmental concerns due to iron sulfides.Anthracite liberation was below 30 wt%.3D modeling estimated a total volume of 7 Mm3,mainly from T08,equaling 11.2 Mt.With its high carbon content and substantial tonnages,re-exploitation or alternative applications could minimize these CMWR piles environmental impact.展开更多
Herein,the Cu(Ⅲ)synthesized from copper plating effluent was developed for the first time to evaluate the onsite degradation performance of heavy metal complexes in the wastewater,thus achieving the purpose of“treat...Herein,the Cu(Ⅲ)synthesized from copper plating effluent was developed for the first time to evaluate the onsite degradation performance of heavy metal complexes in the wastewater,thus achieving the purpose of“treating waste with waste”.The results indicated that synthetic Cu(Ⅲ)presented the excellent decomplexation performance for Cu(Ⅱ)/Ni(Ⅱ)-organic complexes.The removal efficiency of Cu(Ⅱ)/Ni(Ⅱ)-EDTA significantly increased with increasing Cu(Ⅲ)dosage,and the degradation of Cu(Ⅱ)/Ni(Ⅱ)-EDTA by synthetic Cu(Ⅲ)system displayed highly p H-dependent reactivity.The radical quencher experiments confirmed that Cu(Ⅲ)direct oxidation were mainly involved in the degradation of Cu(Ⅱ)-EDTA.Additionally,the continuous decarboxylation process was proven to be the main degradation pathway of Cu(Ⅱ)-EDTA in Cu(Ⅲ)system.The coexisting substances(SO42-,Cl-and fulvic acids)showed little impacts at low level for the removal of Cu(Ⅱ)/Ni(Ⅱ)-EDTA,while retarded the degradation of Cu(Ⅱ)-EDTA slightly at high level,which features high selective oxidation.Encouragingly,it was also effective to remove Cu(Ⅱ)/Ni(Ⅱ)-EDTA from in treating actual Cu/Ni-containing wastewater through synthetic Cu(Ⅲ)treatment.展开更多
Under the background of resource shortage and global warming,it is of great significance to explore the status,influencing factors and carbon emission reduction effect of waste recycling in China after the implementat...Under the background of resource shortage and global warming,it is of great significance to explore the status,influencing factors and carbon emission reduction effect of waste recycling in China after the implementation of new waste classification policy for guiding waste classification and carbon emission accounting.In this research,the temporal and spatial changes and influencing factors of waste recycling were studied from subdistrict level,life-cycle carbon emission reduction was predicted and policy suggestions for waste recycling were proposed.The results showed that after the implementation of new waste classification policy,the amount of recycled waste and the proportion of low-value recycled waste increased by 420.93 t and 2.29%per month on average,respectively.The district center has the largest amount of recycled waste.Income was the main factors affecting waste recycling,and online shopping and takeout could become important sources of recyclable waste.Accounting cradle-to-grave life cycle carbon footprint,waste plastics takes up the most contribution,accounting for 39.11%,and nearly 391.68 Mt CO_(2eq) would be reduced by waste recycling in China by 2030.Therefore,in the process of waste classification,refining waste classification to increase the amount of low-value recyclables,and rationally deploying collection and transportation vehicles to ensure efficient waste recycling are of great significance to achieve the goal of“carbon peaking and carbon neutrality”.展开更多
Objective:Studies on the occupational health risks and experiences of healthcare waste handlers since the decline in coronavirus disease 2019(COVID-19)incidence are scarce in Nigeria.The current study aimed to examine...Objective:Studies on the occupational health risks and experiences of healthcare waste handlers since the decline in coronavirus disease 2019(COVID-19)incidence are scarce in Nigeria.The current study aimed to examine what seemed as the"hidden"and rarely researched area of practice from the standpoint of different stakeholders in a Nigerian Lassa fever treatment hospital.The primary objective was to understand the nature of waste handlers'practices and experiences and identify areas for improvement centred on supporting the development of best practices,in accordance with the World Health Organisation(WHO)guidelines.Methods:This study employed a qualitative case study design,gathering data from healthcare waste handlers(n=34)through four focus groups.Additionally,four in-depth interviews were conducted with ward managers and the infection control team to gain insight into the organisational framing of waste handling practice,the perceived challenges faced by waste handlers from their perspectives,and the provision of training and support.The qualitative data were audio-recorded and transcribed verbatim through manual processes and subjected to a reflexive thematic analysis conducted manually.Results:The findings revealed that waste handlers were subjected to various occupational health risks,including back pain,needlestick injuries,psychological distress,fatigue,anxiety,and prolonged exposure to sunlight.Concerns were raised regarding the inadequate supply of personal protective equipment and other essential tools,which suggests a need for organisational commitment to ensure the continual availability of these resources to protect the health and safety of these employees.A critical issue identified was the lack of comprehensive training for waste handlers,highlighting a form of organisational negligence.The consensual views expressed by the waste handlers indicated a sense of dissatisfaction with their working environment,largely attributable to organisational and societal stigmatisation.Furthermore,the study underscored that the hospital management faced significant financial constraints and advocated for increased funding to effectively implement best practice standards.Conclusion:To effectively manage healthcare waste and reduce hazards to waste handlers,the organisational leadership should prioritise training and support.This initiative will not only benefit the waste handlers but also the patients,other healthcare workers,and the general public.Although the findings focus on the case context of a Nigerian Lassa fever treatment hospital,the wider implications of this study are linked to the role of institutional support for waste handling practice.Moreover,it extends to the potential positions of institutions as displaying a form of"benign anomie"in not ensuring the wellbeing of waste handlers through sufficient regulation and governance focused on prioritisation,processes,and procedures.The study highlights the relevance of embedding WHO guidelines in other similar contexts as part of implementation across institutions involved with waste handling.展开更多
This study aims to analyze waste mitigation policies implemented in South Tangerang City,Indonesia,which faces significant challenges in waste management.Despite various mitigation efforts,issues such as limited landf...This study aims to analyze waste mitigation policies implemented in South Tangerang City,Indonesia,which faces significant challenges in waste management.Despite various mitigation efforts,issues such as limited landfill capacity,low community participation in waste sorting,and inadequate treatment facilities continue to hinder effective waste management.Using a case study approach,the research assesses the effectiveness of existing policies and identifies key barriers.The findings show that poor waste management,characterized by a high volume of waste sent to landfills,leads to severe environmental pollution—including air,soil,and water contamination—and increases the risk of disasters such as landfill collapses.This negative impact is not only felt by the environment,but also has an impact on public health and regional budget efficiency.While initiatives such as the 3R(Reduce,Reuse,Recycle)program and organic waste treatment have been introduced,low community engagement and inadequate treatment facilities remain major obstacles.The study also compares successful waste management policies from developed countries such as Germany,Sweden,and South Korea,offering valuable insights for local policy adaptation.Based on these findings,the study recommends increasing government capacity,improving access to and the quality of Reduce,Reuse,Recycle(WPP3R)Waste Treatment sites,providing incentives,encouraging community involvement,and promoting collaboration between the public and private sectors to achieve more efficient and sustainable waste management.展开更多
The construction of coastal areas generates a substantial volume of waste marine clay(WMC),which poses environmental and safety challenges during the stockpiling process.The improved preparation of WMC as roadbed mate...The construction of coastal areas generates a substantial volume of waste marine clay(WMC),which poses environmental and safety challenges during the stockpiling process.The improved preparation of WMC as roadbed materials emerges as a crucial pathway for resource utilization.However,the engineering performance and durability of roadbed materials prepared from WMC have always been a concern for scholars and engineers.This study employs alkali-activated ground granulated blast-furnace slag(GGBFS)and municipal solid waste incineration bottom ash(MSWIBA)to solidify WMC for preparation of the roadbed materials.The results showed that the combined utilization of alkali-activated GGBFS and MSWIBA to improve WMC can meet the environmental and mechanical requirements of roadbed materials.The incorporation of 5e20%MSWIBA could improve the water stability coefficient and California bearing ratio to more than 85%and 80%,respectively.The durability of roadbed material was significantly improved by addition of MSWIBA.After 12 dryewet cycles,the strength of the material without MSWIBA and with 5%MSWIBA was 0 and 2.87 MPa,respectively.Following analysis of engineering properties and durability,the optimal dosage of MSWIBA was determined to be 5%.The enhanced durability can be attributed to the optimization of material gradation and pore structure achieved through the incorporation of a small quantity of MSWIBA.The carbon emission and normalized global warming potentials of roadbed material treated by MSWIBA and GGBFS were much lower than that of cementitious binders such as ordinary Portland cement.These findings indicate that MSWIBA has the potential to substitute natural aggregates like sand and gravel,effectively improving the durability of roadbed materials and promoting the safe and efficient recycling of solid waste resources.展开更多
The past several decades witnessed tremendous success in controlling global plastic pollution,but most of these achievements do not involve recycling the plastic waste.Herein,we propose a recycling strategy of using p...The past several decades witnessed tremendous success in controlling global plastic pollution,but most of these achievements do not involve recycling the plastic waste.Herein,we propose a recycling strategy of using polyvinyl chloride(PVC) wastes to remove copper ions(Cu_(2+)) from electroplating wastewater for microbial control during wound healing and food preservation.The PVC wastes were recovered and crosslinked by the assistance of diethylenetriamine(DETA),which offered multiple active sites to extract Cu_(2+)ions from electroplating wastewater and in situ reduce to copper nanoparticles(CuNPs) containing crystalline Cu and Cu_(2)O.The obtained composites(i.e.,PVC-DETA@CuNPs) performed excellent antibacterial efficacies(99.999%) against Escherichia coli(E.coli) by disrupting bacterial cell membranes through contact-killing action and oxidative stress.After a series of biological evaluations on wound mice,PVC-DETA@-CuNPs exhibited promising potential in resisting wound bacterial infection,accelerating the healing process,and promoting epithelial regeneration.Interestingly,PVCDETA@CuNPs film was evidenced to delay the spoilage process of strawberries and extend their shelf life by combating with food-borne pathogens.This study presents a recycling approach towards waste reuse and the development of innovative antibacterial materials for microbial control.展开更多
Construction industry is a major contributor of negative impact to the environment. Estimation of construction waste amount is crucial for implementing waste minimization program. Estimation of construction waste amou...Construction industry is a major contributor of negative impact to the environment. Estimation of construction waste amount is crucial for implementing waste minimization program. Estimation of construction waste amount generated is a mean in assessing the potential for waste reduction. Decision-making should be based on quantified measurements expressed in numerical terms to effectively minimize waste produced. A better understanding of C＆D waste generation in terms of causes and sources can be achieved. Lack of benchmarking will hinder the implementation of more sustainable practices in the industry. The aim of this paper is to establish benchmarks on construction waste generation rate in Klang Valley （greater Kuala Lumpur）, Malaysia using appropriate waste quantification method. Nine projects in Klang Valley constructed between 2006-2010 have been selected for this study, which include residential and commercial building projects conducted by a wide range of contractors employing conventional and IBS systems. Wastage level and waste index approaches had been employed in this study as tools for quantifying waste and also for environmental assessment. Types of waste that generated at significant amount, such as concrete, timber, reinforcement bars, tiles, screeds, and plaster are considered. Other factors, such as waste management provision, Environmental Management System （EMS） employed, record-keeping, contractors＇ profile and other related policies are also assessed by conducting interviews with construction personnel. Based on the findings, overall site-management, size of project, and awareness of waste management among construction personnel are the most significant factors that contribute to construction waste generation. Currently, there is still relatively lack of waste minimization awareness among construction players in Malaysia as reflected by poor waste record-keeping, lack of waste sorting and recycling practice, low usage of IBS systems, and lack of supports from top management, clients, and authorities. The roles of construction authorities are essential in achieving the desired benchmark in waste generation rate for Malaysian context. Construction authorities as the policy maker and enforcer could develop and issue new regulations or incentives to stimulate and encourage waste management practices and the use of green building technology, establishing formally standardized systems in record-keeping of quantitative data, introduce useful guidelines and measures, conduct education and training to achieve sustainability and better environmental awareness among Malaysian construction players.展开更多
The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective ...The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective manner.In this review,we investigate the development of industrialwaste-based functional materials for various gas pollutant removal and consider the relevant reaction mechanism according to different types of industrial solid waste.We see a recent effort towards achieving high-performance environmental functional materials via chemical or physical modification,in which the active components,pore size,and phase structure can be altered.The review will discuss the potential of using industrial solid wastes,these modified materials,or synthesized materials from raw waste precursors for the removal of air pollutants,including SO_(2),NO_(x),Hg^(0),H_(2)S,VOCs,and CO_(2).The challenges still need to be addressed to realize this potential and the prospects for future research fully.The suggestions for future directions include determining the optimal composition of these materials,calculating the real reaction rate and turnover frequency,developing effective treatment methods,and establishing chemical component databases of raw industrial solid waste for catalysts/adsorbent preparation.展开更多
This paper presents the perceptions of health workers (HWs) on medical waste management (MWM) issues in Tanzanian hospitals. The perceived total waste generation rates were lower than the actual measurements. Administ...This paper presents the perceptions of health workers (HWs) on medical waste management (MWM) issues in Tanzanian hospitals. The perceived total waste generation rates were lower than the actual measurements. Administrators perceived lower rates than implementers. The results indicated three categories of medical waste which are given due attention, that is, sharps waste, pathological and infectious waste. Other wastes like radioactive, chemical, pharmaceutical, pressurized containers receive very little attention. Container colour coding and labelling was negligible, while improvised containers are still in use. Medical waste is transported within hospitals manually, with little efforts on mechanized transportation. Poor waste storage was observed, while the prominent medical waste treatment technologies are medium temperature incinerators. Off-site transportation of medical waste is practiced, where the waste is finally dumped or buried. The hospitals are currently utilizing public-private partnership schemes for MWM in only one aspect of off-site transportation. Three main problems which require high attention include: Weaknesses in hospital management, poor MWM infrastructure, and lack of skills and knowledge on MWM among HWs. Knowledge and awareness among HWs on health hazards associated with poor MWM is low (with exception of cholera, HIV and typhoid). Few PPE types are supplied and used in the hospitals, leading to poor diseases prevention. There is also low knowledge among HWs on administrative issues related to MWM in Tanzanian hospitals.展开更多
Coal-based soild wastes(CBSWs)are industrial byproducts that can be harmful to the environment.The exploitation and utilization of CBsWs offer societal advantages such as resource conservation,pollution reduction,and ...Coal-based soild wastes(CBSWs)are industrial byproducts that can be harmful to the environment.The exploitation and utilization of CBsWs offer societal advantages such as resource conservation,pollution reduction,and cost-effective production.However,environmentally sustainable management remains a worldwide challenge due to the substantial production volume and limited disposal capacity of CBSWs.The physicochemical properties and utilization of CBSWs are summarized,including fly ash,coal gangue and coal gasification slag.It also presents the current global applications status of CBSWs resources and examines market supply and demand.Subsequently,the paper provides an overview of studies on ways to utilise CBSWs,highlighting the primary avenues of CBSWs resource utilization which are mainly from the fields of chemical materials,metallurgy and agriculture.Furthermore,a comparative evaluation of the various methods for CBSWs resource recovery is conducted,outlining their respective advantages and disadvantages.The future development of CBSWs recycling processes is also discussed.The review concludes that while there is a growing need for attention in CBSWs recycling,its utilization will involve a combination of both large-scale treatment and refinement processes.The paper aims to offer references and insights for the effective utilization and environmental protection of CBSWs.Future direction will focus on the collaborative utilization of CBSWs,emphasizing on the combination of large-scale and high-value utilization.In addition,there is a need to establish a comprehensive database based on on-site production practices,explore on-site solutions to reduce transportation costs,and improve physicochemical properties during the production process.展开更多
Detection of ore waste is crucial for achieving automation in mineral metallurgy production.However,deep learning-based target detection algorithms still face several challenges in iron waste screening,including poor ...Detection of ore waste is crucial for achieving automation in mineral metallurgy production.However,deep learning-based target detection algorithms still face several challenges in iron waste screening,including poor lighting conditions in underground mining environments,dust disturbances,platform vibrations during operation,and limited resources for large-scale computing equipment.These factors contribute to extended computation times and unsatisfactory detection accuracy.To address these challenges,this paper proposes an ore waste detection algorithm based on an improved version of YOLOv5.To enhance feature extraction capabilities,the RepLKNet module is incorporated into the YOLOv5 backbone and neck networks.This module enhances the deformation information of feature extraction with the maximum effective Receptive Field to increase the model's accuracy.The Normalizationbased Attention Module(NAM)was introduced to enhance the attention mechanism by focusing on the most relevant features.This improves accuracy in detecting objects against noisy or unclear backgrounds,thereby further enhancing detection performance while reducing model parameters.Additionally,the loss function is optimized to constrain angular deviation using the SIOU loss function,which prevents the training frame from drifting during training and enhances convergence speed.To validate the performance of the proposed method,we tested it using a self-constructed dataset comprising 1,328 images obtained from the crushing station at Jinchuan Group's No.2 mine.The results indicate that,compared to YOLOv5s on the self-constructed dataset,the proposed algorithm achieves an 18.3%improvement in mAP(0.5),a 54%reduction in FLOPs,and a 52.53%decrease in model parameters.The effectiveness and superiority of the proposed algorithm are demonstrated through case studies and comparative analyses.展开更多
Herein,cure characteristics,morphology,and mechanical properties of natural rubber filled with activated carbon-based materials were investigated.Carbon-based materials were prepared from bagasse,coffee grounds and pi...Herein,cure characteristics,morphology,and mechanical properties of natural rubber filled with activated carbon-based materials were investigated.Carbon-based materials were prepared from bagasse,coffee grounds and pineapple crowns by the pyrolysis method at temperatures in the range of 300℃.As-synthesized carbon materials were characterized by optical microscopy(OM),scanning electron microscopy(SEM),and Fourier-transform infrared spectroscopy(FTIR)to analyze size distribution,morphology,and functional groups,respectively.OM and SEM analysis revealed that particles,flakes,and a small quantity of fiber-like carbon were obtained using bagasse and pineapple crown as raw materials,while honeycomb-like carbon materials can be derived from coffee grounds.To investigate the mechanical properties,natural rubber was filled with carbon black and as-synthesized carbon materials by the internal mixing and compression molding process.Transmission electron microscopy(TEM)was utilized to characterize the dispersion of carbon materials in the rubber matrix.The results of tensile testing showed that the natural rubber mixed with as-synthesized carbon materials from pineapple crowns exhibited 54%and 74%improvement in the ultimate tensile strength and Young’s modulus,respectively,compared with natural rubber without filled carbon materials.The enhancement in mechanical properties by activated carbon materials derived from pineapple crowns can be attributed to the flake-and fiber-like structures and good dispersion of carbon materials in the rubber matrix.In addition,it is higher than that of rubber mixed with carbon black.The results demonstrated that as-synthesized carbon materials from pineapple crowns have the potential materials to substitute carbon black in the rubber compound industry.展开更多
Copper and cobalt were recovered from SICOMINES mining waste rock in the Democratic Republic of Congo.The process mineralogy of the samples was analyzed using scanning electron microscopy and energy dispersive spectro...Copper and cobalt were recovered from SICOMINES mining waste rock in the Democratic Republic of Congo.The process mineralogy of the samples was analyzed using scanning electron microscopy and energy dispersive spectroscopy.The results showed that copper minerals exhibited various forms and uneven particle sizes,while cobalt existed in the form of highly dispersed asbolane,and large amounts of easily slimed gangue minerals were filled in the samples,making it difficult to separate copper and cobalt minerals.The particle size range plays a decisive role in selecting the separation method for the copper−cobalt ore.Gravity separation was suitable for particles ranging from 43 to 246μm,while flotation was more effective for particles below 43μm.After ore grinding and particle size classification,applying a combined gravity separation(shaking table)−flotation method yielded concentrated minerals with a copper recovery of 72.83%and a cobalt recovery of 31.13%.展开更多
文摘To deal with a polluted by-product of coal production,central China’s Shanxi Province has explored a governance path that addresses both the symptoms and root causes.
基金supported by the National Natural Science Foundation of China(No.52436008)the Inner Mongolia Science and Technology Projects,China(Nos.JMRHZX20210003 and 2023YFCY0009)+3 种基金the Huaneng Group Co Ltd.,China(No.HNKJ23-H50)the National Natural Science Foundation of China(No.22408044)the China Postdoctoral Science Foundation(No.2024M761877)the National Key R&D Program of China(No.SQ2024YFD2200039)。
文摘The electromagnetic wave absorption of silicon carbide nanowires is improved by their uniform and diverse cross-structures.This study introduces a sustainable and high value-added method for synthesizing silicon carbide nanowires using lignite and waste silicon powder as raw materials through carbothermal reduction.The staggered structure of nanowires promotes the creation of interfacial polarization,impedance matching,and multiple loss mechanisms,leading to enhanced electromagnetic absorption performance.The silicon carbide nanowires demonstrate outstanding electromagnetic absorption capabilities with the minimum reflection loss of-48.09 d B at10.08 GHz and an effective absorption bandwidth(the reflection loss less than-10 d B)ranging from 8.54 to 16.68 GHz with a thickness of 2.17 mm.This research presents an innovative approach for utilizing solid waste in an environmentally friendly manner to produce broadband silicon carbide composite absorbers.
基金supported by the National Natural Science Foundation of China(No.22176200)the Industrial Innovation Entrepreneurial Team Project of Ordos 2021.
文摘Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may pose certain environmental risks.Snow-melting agents and snow samples were collected and analyzed from highways,arterial roads,footbridges,and other locations in Beijing after the snowstorm in December 2023.It was found that the main component of snow-melting agents was sodium chloride with high concentrations of Cu,Mn,and Zn,which are not regulated in the current policies,despite the recent promotion of environmentally friendly snow-melting agents.The Pb,Zn and Cr contents of some snow samples exceeded the limitation value of surface water quality standards,potentially affecting the soil and water environment near roadsides,although the snow-melting agents comply with relevant standards,which indicates the policy gap in the management of recycled industrial salts.We reviewed and analyzed the relevant standards for snow-melting agents and industrial waste salts proposed nationally and internationally over the past 30 years.Through comparative analysis,we proposed relevant policy recommendations to the existing quality standards of snow-melting agents and the management regulations of industrial waste salts,and the formulation of corresponding usage strategies,aimed at reducing the potential environmental release of heavy metals from the use of snow-melting agents,thereby promoting more sustainable green urban development and environmentally sound waste management.
基金supported by a grant from NIH(R01AI132695)to RM。
文摘Chronic wasting disease—a prion disease affecting cervids:Many neurological conditions,including Alzheimer's and Parkinson's diseases,amyotrophic lateral sclerosis,frontotemporal dementias,among others,are caused by the accumulation of misfolded proteins in the brain.These diseases affect not only humans,but also animals.
文摘In order to address the synergistic optimization of energy efficiency improvement in the waste incineration power plant(WIPP)and renewable energy accommodation,an electricity-hydrogen-waste multi-energy system integrated with phase change material(PCM)thermal storage is proposed.First,a thermal energy management framework is constructed,combining PCM thermal storage with the alkaline electrolyzer(AE)waste heat recovery and the heat pump(HP),while establishing a PCM-driven waste drying system to enhance the efficiency of waste incineration power generation.Next,a flue gas treatment method based on purification-separation-storage coordination is adopted,achieving spatiotemporal decoupling between waste incineration and flue gas treatment.Subsequently,a two-stage optimal dispatching strategy for the multi-energy system is developed:the first stage establishes a dayahead economic dispatch model with the objective of minimizing net system costs,while the second stage introduces model predictive control(MPC)to realize intraday rolling optimization.Finally,The optimal dispatching strategies under different scenarios are obtained using the Gurobi solver,followed by a comparative analysis of the optimized operational outcomes.Simulation results demonstrate that the proposed system optimizes the output and operational states of each unit,simultaneously reducing carbon trading costs while increasing electricity sales revenue.The proposed scheduling strategy demonstrates effective grid peak-shaving functionality,thereby simultaneously improving the system’s economic performance and operational flexibility while providing an innovative technical pathway for municipal solid waste(MSW)resource utilization and low-carbon transformation of energy systems.
文摘A study recently published in Scientific Reports shows that fibers from agricultural waste can make 3D-printed concrete stronger and more environmen-tally friendly.This approach not only gives new life to organic waste but also helps address the environmental issues linked to traditional building materials.The research found that adding natural fibers improves both the strength and the printability of concrete,offering a more efficient and eco-friendly option for modern construction.
基金financial support from the International Research Chairs Initiativea program funded by the International Development Research Centre,Canada(IDRC)facilitated by the Canadian Research Chairs Program(108469-001 and 109418-006).
文摘Jerada coal mining generates extensive coal mine waste rock(CMWR)piles rich in valuable minerals,posing environmental challenges and economic opportunities.This study examines reprocessing feasibility through 3D geometallurgical characterization.Sampling used down the hole hammer drilling technique(DTH)and drone surveys for topographical precision.Over 620 samples from(T01,T02,T08)underwent comprehensive analyses including particle size distribution,x-ray fluorescence(XRF),total sulfur/carbon analysis(S/C),and inductively coupled plasma mass spectrometry(ICP-MS)for physical-chemical characterization.Mineralogical aspects were explored via optical microscopy(OM),X-ray diffraction(XRD),scanning electron microscopy(SEM),electron probe microanalysis(EPMA),and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS).Quantitative mineral evaluation by scanning electron microscope(QEMSCAN)provided mineral insights.Chemical data was used in a 3D block model to quantify residual coal.Results for the three examined CMWR piles(T01,T02,and T08)showed varying D80 from 160 to 300μm,notable carbon content averaged 12.5 wt%(T01),16 wt%(T02),and 8.5 wt%(T08).Sulfur presence exceeded 1 wt%in T08,and potential environmental concerns due to iron sulfides.Anthracite liberation was below 30 wt%.3D modeling estimated a total volume of 7 Mm3,mainly from T08,equaling 11.2 Mt.With its high carbon content and substantial tonnages,re-exploitation or alternative applications could minimize these CMWR piles environmental impact.
基金supported by National Natural Science Foundation of China(Nos.52170092,U22A20403 and 51808406)Hebei Natural Science Foundation(Nos.E2021203140 and B2021203016)。
文摘Herein,the Cu(Ⅲ)synthesized from copper plating effluent was developed for the first time to evaluate the onsite degradation performance of heavy metal complexes in the wastewater,thus achieving the purpose of“treating waste with waste”.The results indicated that synthetic Cu(Ⅲ)presented the excellent decomplexation performance for Cu(Ⅱ)/Ni(Ⅱ)-organic complexes.The removal efficiency of Cu(Ⅱ)/Ni(Ⅱ)-EDTA significantly increased with increasing Cu(Ⅲ)dosage,and the degradation of Cu(Ⅱ)/Ni(Ⅱ)-EDTA by synthetic Cu(Ⅲ)system displayed highly p H-dependent reactivity.The radical quencher experiments confirmed that Cu(Ⅲ)direct oxidation were mainly involved in the degradation of Cu(Ⅱ)-EDTA.Additionally,the continuous decarboxylation process was proven to be the main degradation pathway of Cu(Ⅱ)-EDTA in Cu(Ⅲ)system.The coexisting substances(SO42-,Cl-and fulvic acids)showed little impacts at low level for the removal of Cu(Ⅱ)/Ni(Ⅱ)-EDTA,while retarded the degradation of Cu(Ⅱ)-EDTA slightly at high level,which features high selective oxidation.Encouragingly,it was also effective to remove Cu(Ⅱ)/Ni(Ⅱ)-EDTA from in treating actual Cu/Ni-containing wastewater through synthetic Cu(Ⅲ)treatment.
基金supported by the Construction of Environmental Science and Engineering Discipline for the Goal of Carbon Peaking and Carbon Neutrality Funding comes from Beijing Forestry University(No.2022XKJS0207).
文摘Under the background of resource shortage and global warming,it is of great significance to explore the status,influencing factors and carbon emission reduction effect of waste recycling in China after the implementation of new waste classification policy for guiding waste classification and carbon emission accounting.In this research,the temporal and spatial changes and influencing factors of waste recycling were studied from subdistrict level,life-cycle carbon emission reduction was predicted and policy suggestions for waste recycling were proposed.The results showed that after the implementation of new waste classification policy,the amount of recycled waste and the proportion of low-value recycled waste increased by 420.93 t and 2.29%per month on average,respectively.The district center has the largest amount of recycled waste.Income was the main factors affecting waste recycling,and online shopping and takeout could become important sources of recyclable waste.Accounting cradle-to-grave life cycle carbon footprint,waste plastics takes up the most contribution,accounting for 39.11%,and nearly 391.68 Mt CO_(2eq) would be reduced by waste recycling in China by 2030.Therefore,in the process of waste classification,refining waste classification to increase the amount of low-value recyclables,and rationally deploying collection and transportation vehicles to ensure efficient waste recycling are of great significance to achieve the goal of“carbon peaking and carbon neutrality”.
基金Bangor University,UK supported this study through the International Science Partnerships Fund(ISPF)。
文摘Objective:Studies on the occupational health risks and experiences of healthcare waste handlers since the decline in coronavirus disease 2019(COVID-19)incidence are scarce in Nigeria.The current study aimed to examine what seemed as the"hidden"and rarely researched area of practice from the standpoint of different stakeholders in a Nigerian Lassa fever treatment hospital.The primary objective was to understand the nature of waste handlers'practices and experiences and identify areas for improvement centred on supporting the development of best practices,in accordance with the World Health Organisation(WHO)guidelines.Methods:This study employed a qualitative case study design,gathering data from healthcare waste handlers(n=34)through four focus groups.Additionally,four in-depth interviews were conducted with ward managers and the infection control team to gain insight into the organisational framing of waste handling practice,the perceived challenges faced by waste handlers from their perspectives,and the provision of training and support.The qualitative data were audio-recorded and transcribed verbatim through manual processes and subjected to a reflexive thematic analysis conducted manually.Results:The findings revealed that waste handlers were subjected to various occupational health risks,including back pain,needlestick injuries,psychological distress,fatigue,anxiety,and prolonged exposure to sunlight.Concerns were raised regarding the inadequate supply of personal protective equipment and other essential tools,which suggests a need for organisational commitment to ensure the continual availability of these resources to protect the health and safety of these employees.A critical issue identified was the lack of comprehensive training for waste handlers,highlighting a form of organisational negligence.The consensual views expressed by the waste handlers indicated a sense of dissatisfaction with their working environment,largely attributable to organisational and societal stigmatisation.Furthermore,the study underscored that the hospital management faced significant financial constraints and advocated for increased funding to effectively implement best practice standards.Conclusion:To effectively manage healthcare waste and reduce hazards to waste handlers,the organisational leadership should prioritise training and support.This initiative will not only benefit the waste handlers but also the patients,other healthcare workers,and the general public.Although the findings focus on the case context of a Nigerian Lassa fever treatment hospital,the wider implications of this study are linked to the role of institutional support for waste handling practice.Moreover,it extends to the potential positions of institutions as displaying a form of"benign anomie"in not ensuring the wellbeing of waste handlers through sufficient regulation and governance focused on prioritisation,processes,and procedures.The study highlights the relevance of embedding WHO guidelines in other similar contexts as part of implementation across institutions involved with waste handling.
文摘This study aims to analyze waste mitigation policies implemented in South Tangerang City,Indonesia,which faces significant challenges in waste management.Despite various mitigation efforts,issues such as limited landfill capacity,low community participation in waste sorting,and inadequate treatment facilities continue to hinder effective waste management.Using a case study approach,the research assesses the effectiveness of existing policies and identifies key barriers.The findings show that poor waste management,characterized by a high volume of waste sent to landfills,leads to severe environmental pollution—including air,soil,and water contamination—and increases the risk of disasters such as landfill collapses.This negative impact is not only felt by the environment,but also has an impact on public health and regional budget efficiency.While initiatives such as the 3R(Reduce,Reuse,Recycle)program and organic waste treatment have been introduced,low community engagement and inadequate treatment facilities remain major obstacles.The study also compares successful waste management policies from developed countries such as Germany,Sweden,and South Korea,offering valuable insights for local policy adaptation.Based on these findings,the study recommends increasing government capacity,improving access to and the quality of Reduce,Reuse,Recycle(WPP3R)Waste Treatment sites,providing incentives,encouraging community involvement,and promoting collaboration between the public and private sectors to achieve more efficient and sustainable waste management.
基金supported by the National Key Research and Development Program(Grant No.2023YFC3707802)National Natural Science Foundation of China(Grant No.42107185)International Partnership Program of Chinese Academy of Sciences(Grant No.115242KYSB20200002).
文摘The construction of coastal areas generates a substantial volume of waste marine clay(WMC),which poses environmental and safety challenges during the stockpiling process.The improved preparation of WMC as roadbed materials emerges as a crucial pathway for resource utilization.However,the engineering performance and durability of roadbed materials prepared from WMC have always been a concern for scholars and engineers.This study employs alkali-activated ground granulated blast-furnace slag(GGBFS)and municipal solid waste incineration bottom ash(MSWIBA)to solidify WMC for preparation of the roadbed materials.The results showed that the combined utilization of alkali-activated GGBFS and MSWIBA to improve WMC can meet the environmental and mechanical requirements of roadbed materials.The incorporation of 5e20%MSWIBA could improve the water stability coefficient and California bearing ratio to more than 85%and 80%,respectively.The durability of roadbed material was significantly improved by addition of MSWIBA.After 12 dryewet cycles,the strength of the material without MSWIBA and with 5%MSWIBA was 0 and 2.87 MPa,respectively.Following analysis of engineering properties and durability,the optimal dosage of MSWIBA was determined to be 5%.The enhanced durability can be attributed to the optimization of material gradation and pore structure achieved through the incorporation of a small quantity of MSWIBA.The carbon emission and normalized global warming potentials of roadbed material treated by MSWIBA and GGBFS were much lower than that of cementitious binders such as ordinary Portland cement.These findings indicate that MSWIBA has the potential to substitute natural aggregates like sand and gravel,effectively improving the durability of roadbed materials and promoting the safe and efficient recycling of solid waste resources.
基金financially supported by the National Energy R&D Center of Petroleum Refining Technology (RIPP,SINOPEC)the National Natural Science Foundation of China (Nos.22062017 and 22164015)+2 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region (Nos.2024ZD10 and 2023QN02011)the Program of Higher-Level Talents of Inner Mongolia University (No.10000-22311201/035)the Research Program of science and technology at Universities of Inner Mongolia Autonomous Region (No.NJZZ23091)
文摘The past several decades witnessed tremendous success in controlling global plastic pollution,but most of these achievements do not involve recycling the plastic waste.Herein,we propose a recycling strategy of using polyvinyl chloride(PVC) wastes to remove copper ions(Cu_(2+)) from electroplating wastewater for microbial control during wound healing and food preservation.The PVC wastes were recovered and crosslinked by the assistance of diethylenetriamine(DETA),which offered multiple active sites to extract Cu_(2+)ions from electroplating wastewater and in situ reduce to copper nanoparticles(CuNPs) containing crystalline Cu and Cu_(2)O.The obtained composites(i.e.,PVC-DETA@CuNPs) performed excellent antibacterial efficacies(99.999%) against Escherichia coli(E.coli) by disrupting bacterial cell membranes through contact-killing action and oxidative stress.After a series of biological evaluations on wound mice,PVC-DETA@-CuNPs exhibited promising potential in resisting wound bacterial infection,accelerating the healing process,and promoting epithelial regeneration.Interestingly,PVCDETA@CuNPs film was evidenced to delay the spoilage process of strawberries and extend their shelf life by combating with food-borne pathogens.This study presents a recycling approach towards waste reuse and the development of innovative antibacterial materials for microbial control.
文摘Construction industry is a major contributor of negative impact to the environment. Estimation of construction waste amount is crucial for implementing waste minimization program. Estimation of construction waste amount generated is a mean in assessing the potential for waste reduction. Decision-making should be based on quantified measurements expressed in numerical terms to effectively minimize waste produced. A better understanding of C＆D waste generation in terms of causes and sources can be achieved. Lack of benchmarking will hinder the implementation of more sustainable practices in the industry. The aim of this paper is to establish benchmarks on construction waste generation rate in Klang Valley （greater Kuala Lumpur）, Malaysia using appropriate waste quantification method. Nine projects in Klang Valley constructed between 2006-2010 have been selected for this study, which include residential and commercial building projects conducted by a wide range of contractors employing conventional and IBS systems. Wastage level and waste index approaches had been employed in this study as tools for quantifying waste and also for environmental assessment. Types of waste that generated at significant amount, such as concrete, timber, reinforcement bars, tiles, screeds, and plaster are considered. Other factors, such as waste management provision, Environmental Management System （EMS） employed, record-keeping, contractors＇ profile and other related policies are also assessed by conducting interviews with construction personnel. Based on the findings, overall site-management, size of project, and awareness of waste management among construction personnel are the most significant factors that contribute to construction waste generation. Currently, there is still relatively lack of waste minimization awareness among construction players in Malaysia as reflected by poor waste record-keeping, lack of waste sorting and recycling practice, low usage of IBS systems, and lack of supports from top management, clients, and authorities. The roles of construction authorities are essential in achieving the desired benchmark in waste generation rate for Malaysian context. Construction authorities as the policy maker and enforcer could develop and issue new regulations or incentives to stimulate and encourage waste management practices and the use of green building technology, establishing formally standardized systems in record-keeping of quantitative data, introduce useful guidelines and measures, conduct education and training to achieve sustainability and better environmental awareness among Malaysian construction players.
基金supported by National Natural Science Foundation of China(Grant No.52270106 and 22266021)Yunnan Major Scientific and Technological Projects(grant No.202202AG050005)Yunnan Fundamental Research Projects(grant No.202201AT070116).
文摘The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective manner.In this review,we investigate the development of industrialwaste-based functional materials for various gas pollutant removal and consider the relevant reaction mechanism according to different types of industrial solid waste.We see a recent effort towards achieving high-performance environmental functional materials via chemical or physical modification,in which the active components,pore size,and phase structure can be altered.The review will discuss the potential of using industrial solid wastes,these modified materials,or synthesized materials from raw waste precursors for the removal of air pollutants,including SO_(2),NO_(x),Hg^(0),H_(2)S,VOCs,and CO_(2).The challenges still need to be addressed to realize this potential and the prospects for future research fully.The suggestions for future directions include determining the optimal composition of these materials,calculating the real reaction rate and turnover frequency,developing effective treatment methods,and establishing chemical component databases of raw industrial solid waste for catalysts/adsorbent preparation.
文摘This paper presents the perceptions of health workers (HWs) on medical waste management (MWM) issues in Tanzanian hospitals. The perceived total waste generation rates were lower than the actual measurements. Administrators perceived lower rates than implementers. The results indicated three categories of medical waste which are given due attention, that is, sharps waste, pathological and infectious waste. Other wastes like radioactive, chemical, pharmaceutical, pressurized containers receive very little attention. Container colour coding and labelling was negligible, while improvised containers are still in use. Medical waste is transported within hospitals manually, with little efforts on mechanized transportation. Poor waste storage was observed, while the prominent medical waste treatment technologies are medium temperature incinerators. Off-site transportation of medical waste is practiced, where the waste is finally dumped or buried. The hospitals are currently utilizing public-private partnership schemes for MWM in only one aspect of off-site transportation. Three main problems which require high attention include: Weaknesses in hospital management, poor MWM infrastructure, and lack of skills and knowledge on MWM among HWs. Knowledge and awareness among HWs on health hazards associated with poor MWM is low (with exception of cholera, HIV and typhoid). Few PPE types are supplied and used in the hospitals, leading to poor diseases prevention. There is also low knowledge among HWs on administrative issues related to MWM in Tanzanian hospitals.
基金supported by the following:“National Natural Science Foundation of China”(22478231)“Natural Science Foundation of Henan”(242300421449)“Fundamental Research Program of Shanxi Province”(202403021221011).
文摘Coal-based soild wastes(CBSWs)are industrial byproducts that can be harmful to the environment.The exploitation and utilization of CBsWs offer societal advantages such as resource conservation,pollution reduction,and cost-effective production.However,environmentally sustainable management remains a worldwide challenge due to the substantial production volume and limited disposal capacity of CBSWs.The physicochemical properties and utilization of CBSWs are summarized,including fly ash,coal gangue and coal gasification slag.It also presents the current global applications status of CBSWs resources and examines market supply and demand.Subsequently,the paper provides an overview of studies on ways to utilise CBSWs,highlighting the primary avenues of CBSWs resource utilization which are mainly from the fields of chemical materials,metallurgy and agriculture.Furthermore,a comparative evaluation of the various methods for CBSWs resource recovery is conducted,outlining their respective advantages and disadvantages.The future development of CBSWs recycling processes is also discussed.The review concludes that while there is a growing need for attention in CBSWs recycling,its utilization will involve a combination of both large-scale treatment and refinement processes.The paper aims to offer references and insights for the effective utilization and environmental protection of CBSWs.Future direction will focus on the collaborative utilization of CBSWs,emphasizing on the combination of large-scale and high-value utilization.In addition,there is a need to establish a comprehensive database based on on-site production practices,explore on-site solutions to reduce transportation costs,and improve physicochemical properties during the production process.
基金supported by the Department of science and technology of Shaanxi Province(NO.2023-ZDLGY-24).
文摘Detection of ore waste is crucial for achieving automation in mineral metallurgy production.However,deep learning-based target detection algorithms still face several challenges in iron waste screening,including poor lighting conditions in underground mining environments,dust disturbances,platform vibrations during operation,and limited resources for large-scale computing equipment.These factors contribute to extended computation times and unsatisfactory detection accuracy.To address these challenges,this paper proposes an ore waste detection algorithm based on an improved version of YOLOv5.To enhance feature extraction capabilities,the RepLKNet module is incorporated into the YOLOv5 backbone and neck networks.This module enhances the deformation information of feature extraction with the maximum effective Receptive Field to increase the model's accuracy.The Normalizationbased Attention Module(NAM)was introduced to enhance the attention mechanism by focusing on the most relevant features.This improves accuracy in detecting objects against noisy or unclear backgrounds,thereby further enhancing detection performance while reducing model parameters.Additionally,the loss function is optimized to constrain angular deviation using the SIOU loss function,which prevents the training frame from drifting during training and enhances convergence speed.To validate the performance of the proposed method,we tested it using a self-constructed dataset comprising 1,328 images obtained from the crushing station at Jinchuan Group's No.2 mine.The results indicate that,compared to YOLOv5s on the self-constructed dataset,the proposed algorithm achieves an 18.3%improvement in mAP(0.5),a 54%reduction in FLOPs,and a 52.53%decrease in model parameters.The effectiveness and superiority of the proposed algorithm are demonstrated through case studies and comparative analyses.
基金funded by Faculty of Engineering,Burapha University,grant number 003/2567.
文摘Herein,cure characteristics,morphology,and mechanical properties of natural rubber filled with activated carbon-based materials were investigated.Carbon-based materials were prepared from bagasse,coffee grounds and pineapple crowns by the pyrolysis method at temperatures in the range of 300℃.As-synthesized carbon materials were characterized by optical microscopy(OM),scanning electron microscopy(SEM),and Fourier-transform infrared spectroscopy(FTIR)to analyze size distribution,morphology,and functional groups,respectively.OM and SEM analysis revealed that particles,flakes,and a small quantity of fiber-like carbon were obtained using bagasse and pineapple crown as raw materials,while honeycomb-like carbon materials can be derived from coffee grounds.To investigate the mechanical properties,natural rubber was filled with carbon black and as-synthesized carbon materials by the internal mixing and compression molding process.Transmission electron microscopy(TEM)was utilized to characterize the dispersion of carbon materials in the rubber matrix.The results of tensile testing showed that the natural rubber mixed with as-synthesized carbon materials from pineapple crowns exhibited 54%and 74%improvement in the ultimate tensile strength and Young’s modulus,respectively,compared with natural rubber without filled carbon materials.The enhancement in mechanical properties by activated carbon materials derived from pineapple crowns can be attributed to the flake-and fiber-like structures and good dispersion of carbon materials in the rubber matrix.In addition,it is higher than that of rubber mixed with carbon black.The results demonstrated that as-synthesized carbon materials from pineapple crowns have the potential materials to substitute carbon black in the rubber compound industry.
基金National Key Research and Development Program of China(No.2020YFC1909202)Major Science and Technology Program of Yunnan Province,China(No.202202AB080012)for financial support。
文摘Copper and cobalt were recovered from SICOMINES mining waste rock in the Democratic Republic of Congo.The process mineralogy of the samples was analyzed using scanning electron microscopy and energy dispersive spectroscopy.The results showed that copper minerals exhibited various forms and uneven particle sizes,while cobalt existed in the form of highly dispersed asbolane,and large amounts of easily slimed gangue minerals were filled in the samples,making it difficult to separate copper and cobalt minerals.The particle size range plays a decisive role in selecting the separation method for the copper−cobalt ore.Gravity separation was suitable for particles ranging from 43 to 246μm,while flotation was more effective for particles below 43μm.After ore grinding and particle size classification,applying a combined gravity separation(shaking table)−flotation method yielded concentrated minerals with a copper recovery of 72.83%and a cobalt recovery of 31.13%.
