The Effects of Environmental Materials on Pb and Cd Solidification

The leaching experiments of soils contaminated by heavy metal Pb or Cd were conducted with four kinds of environmental materials, polymer absorbent material （PAM）, coal-based nutrient （CBN）, mineral adsorption material （MAM） and mineral chemical material （MCM） to explore Pb and Cd solidification effects. Then the Fourier Transform Infrared Spectrometer （FTIR） analysis was used to explain the solidification mechanism of the effective environmental materials, and the Scanning Electron Microscope （SEM） test was applied to demonstrate their solidifi- cation morphology. The results showed that MCM was the best material for Pb solidification, and Pb concentration in the leachate accounted for 68.6% of that in CK; MAM was the best material for Cd solidification, and the Cd concentration accounted for 74.6% of that in CK. The FTIR analysis showed the functional groups, such as C-OH in MCM and COOH in MAM, could explain the adsorption mechanism by ion exchange and chemical bond force. The SEM images indicated there were obvious adsorption morphological changes in MCM and MAM after adsorbing Pb and Cd respectively.

Preparation of Phase Change Concrete Using Environmentally FriendlyMaterials and Its Performance Study

The control of carbon emissions and energy conservation,and environmental protection are hot spots of global concern.In this paper,phase change paraffin wax is applied to porous materials for adsorption and storage,and nature’s eco-friendly materials are selected as the porous matrix to propose an eco-friendly phase change concrete using eco-friendly materials as raw materials.It was obtained that the strength of the phase change concrete utilizing environmentally friendly materials was 25.4%to 36.8%lower than that of ordinary concrete,while some of the phase change light aggregates were found to produce slip damage with the cement paste in the damage study.By constructing a small-sized test room for thermal properties,we obtained a phase change concrete that utilizes environmentally friendly materials to control the temperature better than the commonly studied phase change concrete,with a peak temperature drop of up to 2.6℃ in the phase change test room compared to the normal test room and a delay in the peak temperature.

Evaluation of Environmental Impacts of Traction Motor Production and Disposal

By the application of life cycle assessment(LCA) methodology, this paper estimates the environmental impacts of production and disposal of traction motors used in electric vehicles in China. The results show that the total energy use, the criteria emissions and the greenhouse gases(GHG) emissions of a traction motor production and disposal are about 2,899,MJ, 4.5,kg and 259.5,kg per motor, respectively. Among the regulated emissions, the SOxemission ranks first by total mass, followed by CO, PM10, NOx, PM2.5, and volatile organic compound(VOC). The motor material production stage accounts for most of the energy consumption and emissions, followed by the assembly stage and the end-of-life disposal stage. In this study, the environmental performance analysis is extended to the comparison between the use of secondary material and primary material for the material production stage. It is found that using 100% secondary material results in a 52.9% reduction in energy consumption, a 49.8% reduction in regulated emissions, and a 49.3% reduction in GHG emissions compared with the use of 100% primary material.

A safe haven of SARS-CoV-2 in the environment:Prevalence and potential transmission risks in the effluent,sludge,and biosolids

The novel coronavirus,SARS-CoV-2,which has caused millions of death globally is recognized to be unstable and recalcitrant in the environment,especially in the way it has been evolving to form new and highly transmissible variants.Of particular concerns are human-environment interactions and the handling and reusing the environmental materials,such as effluents,sludge,or biosolids laden with the SARS-CoV-2 without adequate treatments,thereby suggesting potential transmission and health risks.This study assesses the prevalence of SARS-CoV-2 RNA in effluents,sludge,and biosolids.Further,we evaluate the environmental,ecological,and health risks of reusing these environmental materials by wastewater/sludge workers and farmers.A systematic review of literature from the Scopus database resulted in a total of 21 articles(11 for effluents,8 for sludge,and 2 for biosolids)that met the criteria for meta-analysis,which are then subdivided into 30 meta-analyzed studies.The prevalence of SAR-CoV-2 RNA in effluent and sludge based on random-effect models are 27.51 and 1012.25,respectively,with a 95%CI between 6.14 and 48.89 for the effluent,and 104.78 and 1019.71 for the sludge.However,the prevalence of SARS-CoV-2 RNA in the biosolids based on the fixed-effect model is 30.59,with a 95%CI between 10.10 and 51.08.The prevalence of SARS-CoV-2 RNA in environmental materials indicates the inefficiency in some of the treatment systems currently deployed to inactivate and remove the novel virus,which could be a potential health risk concern to vulnerable wastewater workers in particular,and the environmental and ecological issues for the population at large.This timely review portends the associated risks in handling and reusing environmental materials without proper and adequate treatments.

Progress of Materials Science in Space Technology in China(2020-2022)

In this paper,the main research work and related reports of materials science research in China’s space technology field during 2020-2022 are summarized.This paper covers Materials Sciences in Space Environment,Materials Sciences for Space Environment,Materials Behavior in Space Environment and Space experimental hardware for material investigation.With the rapid development of China’s space industry,more scientists will be involved in materials science,space technology and earth science researches.In the future,a series of disciplines such as space science,machinery,artificial intelligence,digital twin and big data will be further integrated with materials science,and space materials will also usher in new development opportunities.

Progress on the Structures and Functions of Aerogels

Aerogel materials possess a wide variety of excellent functions,hence a striking number of applications have developed for them.In this paper,we present a historic review of the aerogel materials,showing the main concepts,research methods,important scientific problems,formation mechanism,structure characteristics and essence of aerogel.More applications are evolving as the scientific and engineering community,which becomes familiar with the unusual and exceptional physical properties of aerogels.In addition,we also discuss the huge development potential and prospect of polysaccharide aerogels as the research trend in the future.

SPACE CARGO TRANSPORT BAGS THROUGH MEMBRANE WATER TREATMENT ELEMENTS TO SPACE ARCHITECTURE BUILDING ELEMENT:A TOTAL PRODUCT SUSTAINABILITY AND LIFE CYCLE DESIGN OPTIMIZATION EXPERIMENT

The CTB Water Wall project is a maximal product life cycle utilization concept study by members of the space architecture design community.Its function is to demonstrate a human space activity Cargo Transport Bag(CTB)that becomes a primary water recycling membrane element after delivery of cargo,and then a permanent architectural building block for sustainable space habitation after its use in water treatment is complete.As such,it is intended as an experiment in radical life cycle product optimization in an extremely mass-constrained application environment(human space operations).It also introduces some fundamentally interesting concepts in architectural use of waste materials in extreme environments.Finally,it is in some ways a simple,tactile and visual demonstration of how far sustainable product design can be taken,if the motivation and technical justification are present.

Graphitic carbon nitride with different dimensionalities for energy and environmental applications

As a metal-free semiconductor,graphitic carbon nitride(g-C3N4)has received extensive attention due to its high stability,nontoxicity,facile and low-cost synthesis,appropriate band gap in the visible spectral range and wide availability of resources.The dimensions of g-C3N4 can influence the regime of the confinement of electrons,and consequently,g-C3N4 with various dimensionalities shows different properties,making them available for many stimulating applications.Although there are some reviews focusing on the synthesis strategy and applications of g-C3N4,there is still a lack of comprehensive review that systemically summarises the synthesis and application of different dimensions of g-C3N4,which can provide an important theoretical and practical basis for the development of g-C3N4 with different dimensionalities and maximises their potential in diverse applications.By reviewing the latest progress of g-C3N4 studies,we aim to summarise the preparation of g-C3N4 with different dimensionalities using various structural engineering strategies,discuss the fundamental bottlenecks of currently existing methods and their solution strategies,and explore their applications in energy and environmental applications.Furthermore,it also puts forward the views on the future research direction of these unique materials.

(La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4: A high-entropy rare-earth phosphate monazite ceramic with low thermal conductivity and good compatibility with Al2O3

Low thermal conductivity, matched thermal expansion coefficient and good compatibility are general requirements for the environmental/thermal barrier coatings(EBCs/TBCs) and interphases for Al2O3 f/Al2O3 composites. In this work, a novel high-entropy(HE) rare-earth phosphate monazite ceramic (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 is designed and successfully synthesized. This new type of HE rare-earth phosphate monazite exhibits good chemical compatibility with Al2O3, without reaction with Al2O3 as high as 1600℃ in air. Moreover, the thermal expansion coefficient(TEC) of HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4(8.9 × 10^-6/℃ at 300–1000℃) is close to that of Al2O3. The thermal conductivity of HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 at room temperature is as low as 2.08 W·m^-1·K^-1, which is about 42% lower than that of La PO4. Good chemical compatibility, close TEC to that of Al2O3, and low thermal conductivity indicate that HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 is suitable as a candidate EBC/TBC material and an interphase for Al2O3 f/Al2O3 composites.

Interaction of multicomponent disilicate(Yb_(0.2)Y_(0.2)Lu_(0.2)Sc_(0.2)Gd_(0.2))_(2)Si_(2)O_(7)with molten calcia-magnesia-aluminosilicate

Environmental barrier coating(EBC)materials that are resistant against molten calcia-magnesia-aluminosilicate(CMAS)corrosion are urgently required.Elerein,multicomponent rare-earth(RE)disilicate((Yb_(0.2)Y_(0.2)Lu_(0.2)Sc_(0.2)Gd_(0.2))_(2)Si_(2)O_(7),(5RE)_(2)Si_(2)O_(7))was investigated with regard to its CMAS interaction behavior at 1400°C.Compared with the individual RE disilicates,the(5RE)2Si2C>7 material exhibited improved resistance against CMAS attack.The dominant process involved in the interaction of(5RE)_(2)Si_(2)O_(7)with CMAS was reaction-recrystallization.A dense and continuous reaction layer protected the substrate from rapid corrosion at high temperatures.The results demonstrated that multicomponent strategy of RE species in disilicate can provide a new perspective in the development of promising EBC materials with improved corrosion resistance.