The significant amount of ash content in agricultural biomass presents an enormous challenge for efficient conversion processes.In addressing this issue,various deashing treatments have been tested and established,inc...The significant amount of ash content in agricultural biomass presents an enormous challenge for efficient conversion processes.In addressing this issue,various deashing treatments have been tested and established,including simple leaching techniques,which can either be performed with or without the addition of chemical agents.These techniques hold promise for improving the deashing efficiency while potentially altering the structural and chemical composition of biomass,specifically lignin content,which is the key focus of this review.This review starts by exploring the presence of ash in agricultural residues and its impact on biomass properties.Next,this review examines deashing strategies aimed at reducing ash levels in biomass followed by analysis of the resulting changes in lignin physical and chemical properties as well as its thermal characteristics.The final part of this review is concluded by the discussion on the limitations of current approaches and the possible future directions to address the challenges covering the environmental impacts of the deashing treatments.A green process approach is emphasized as a sustainable solution with the aim to minimize negative environmental impacts associated with chemical usage during deashing.Finally,this review highlights the potential for ash recovery as a byproduct of the deashing processes,paving the way for an integrative,closed-loop approach within the biorefinery concept.展开更多
Production of glass-ceramics by sintering the molten slag obtained from electric arc furnace treatment of fly ash was investigated. The effect of washing pretreatment prior to melting the fly ash on the microstructure...Production of glass-ceramics by sintering the molten slag obtained from electric arc furnace treatment of fly ash was investigated. The effect of washing pretreatment prior to melting the fly ash on the microstructure and properties of the glass-ceramics was examined. The results show that washing pretreatment of fly ash can decrease alkali metal chloride and increase network former in fly ash, which results in the increase of peak crystallization temperature of parent glass and strengthening of properties of bending strength and chemical stability of the glass-ceramics. The optimal heat treatment temperature for parent glass of washed fly ash is 1 173 K, at which the crystalline phase of glass-ceramics is composed of gelignite （Ca2A12SiO7） and akermanite （Ca2MgSi207）. Glass-ceramics produced at optimal heat treatment temperature are excellent in term of the physical and chemical properties and leaching characteristics, indicating attractive potential as substitute of nature materials.展开更多
Dry ashing is an established method. Ashing whole blood samples are, however, often difficult to carry out with significant sample loss, and the procedure is not well documented. A new procedure has been devel- oped a...Dry ashing is an established method. Ashing whole blood samples are, however, often difficult to carry out with significant sample loss, and the procedure is not well documented. A new procedure has been devel- oped and optimized to dry-ash whole blood samples for trace metal analyses. The procedure reduces both the dry-ashing time by more than two thirds and sample loss. The ashed sample can be readily used in subse- quent, simultaneous or individual analysis of several metals by ICP-OES, as demonstrated in the analysis of a whole blood sample. The new procedure is simple, inexpensive, and faster than the established method.展开更多
The coal filter cake is a product of fine coal after floatation which has an ash content of 7-13%, water content of 30±2%, and a particle size of less than 1 mm. The ash content was measured by the intensity of t...The coal filter cake is a product of fine coal after floatation which has an ash content of 7-13%, water content of 30±2%, and a particle size of less than 1 mm. The ash content was measured by the intensity of the single backscattered gamma-ray, and its accuracy is mainly dependent on the energy of the gamma-ray. The 238Pu low energy photon source is selected in this work. The energy of its gamma-ray is 15 keV, which can result not only in the best sensitivity, but also in the lowest contribution to the environment radiation. The root mean square deviation of the ash measurement is±0.33% (±1σ).展开更多
Heavy metal stabilization and alkali neutralization are crucial for the management of municipal solid waste incineration fly ash(MSWI FA).In this study,the effects of oxalic acid(OA)and citric acid(CA)washing on heavy...Heavy metal stabilization and alkali neutralization are crucial for the management of municipal solid waste incineration fly ash(MSWI FA).In this study,the effects of oxalic acid(OA)and citric acid(CA)washing on heavy metal migration and alkali changes were investigated.Besides,three agents were selected to stabilize acid-washed fly ash(FA),and the effects of heavy metal stabilization under different disposal environments and the changes in their form distributions were comparatively analyzed.The experimental results demonstrated that with increasing organic acid concentration,the amount of Cd and Pb extracted from MSWI FA increased,whereas the amount of alkalis tended to decrease.Moreover,the leaching concentration of heavy metals and the percentage of unstable forms increased after acid washing.The alkalis content in the products decreased to 7.91-8.75 after stabilization,which met the standards of hazardous waste landfills.Compared with other agents,sodium diethyldithiocarbamate(DDTC)exhibited excellent heavy metal stabilization performance.After the addition of 1%DDTC,the leaching concentrations of Cd and Pb decreased to values lower than the national standard limit.Additionally,the curing rates of Cd and Pb were greater than 98%under the two leaching conditions.With the addition of DDTC,the percentage of stable forms increased,and the percentages of stable Cd and Pb forms increased to 87.68%and 99.03%,respectively,after treatment with 2%DDTC.The above results corroborated that CA coupled with DDTC stabilization can significantly reduce Cd and Pb toxicity and neutralize alkalinity in FA.展开更多
Phase change memory （PCM） has been regarded as a promising candidate for the next generation of nonvolatile memory. To decrease the power required to reset the PCM cell, titanium nitride （TIN） is preferred to be u...Phase change memory （PCM） has been regarded as a promising candidate for the next generation of nonvolatile memory. To decrease the power required to reset the PCM cell, titanium nitride （TIN） is preferred to be used as the bottom electrode of PCM due to its low thermal and suitable electrical conductivity. However, during the manufacture of PCM cell in 40 nm process node, abnormally high and discrete distribution of the resistance of TiN bottom electrode was found, which might be induced by the surface oxidation of TiN bottom electrode during the photoresist ashing process by oxygen plasma. In this work, we have studied the oxidation of TiN and found that with the increasing oxygen plasma ashing time, the thickness of the TiO2 layer became thicker and the state of the TiO2 layer changed from amorphous to crystalline, respectively. The resistance of TiN electrode contact chain with 4-5 nm TiO2 layer was confirmed to be almost three-orders of magnitude higher than that of pure TiN electrode, which led to the failure issue of PCM cell. We efficiently removed the oxidation TiO2 layer by a chemical mechanical polishing （CMP） process, and we eventually recovered the resistance of TiN bottom electrode from 1×10^5Ω/via back to 6×10^2 Ωvia and successfully achieved a uniform resistance distribution of the TiN bottom electrode.展开更多
In order to realize the comprehensive utilization of industrial solid waste rice husk ash and heavy metal cadmium contaminated soil,rice husk ash-based geopolymer prepared by alkaline activator was used to modify cadm...In order to realize the comprehensive utilization of industrial solid waste rice husk ash and heavy metal cadmium contaminated soil,rice husk ash-based geopolymer prepared by alkaline activator was used to modify cadmium contaminated soil.The main physical and chemical properties of rice husk ash were clarified by SEM,XRF and X-ray diffraction.The unconfined compressive strength test and toxicity leaching test were carried out on the modified soil.Combined with FTIR and TG micro-level,the solidification mechanism of rice husk ash-based geopolymer solidified cadmium contaminated soil was discussed.The results show that the strength of geopolymer modified soil is significantly higher than that of plain soil,and the unconfined compressive strength at 7 d age is 4.2 times that of plain soil.The strength of modified soil with different dosage of geopolymer at 28 d age is about 36% to 40% higher than that of modified soil at 7 d age.Geopolymer has a significant effect on the leaching of heavy metals in contaminated soil.When the cadmium content is 100 mg/kg,it meets the standard limit.In the process of complex depolymerization-condensation reaction,on the one hand,geopolymers are cemented and agglomerated to form a complex spatial structure,which affects the macro and micro characteristics of soil.On the other hand,it has significant adsorption,precipitation and replacement effects on heavy metal ions in soil,showing good strength and low heavy metal leaching toxicity.展开更多
Fly ash,as a byproduct of municipal solid waste incineration,contains several kinds of pollutants,especially dissolvable salts that cause a severe challenge for fly ash disposal.Washing combined with cement kiln co-pr...Fly ash,as a byproduct of municipal solid waste incineration,contains several kinds of pollutants,especially dissolvable salts that cause a severe challenge for fly ash disposal.Washing combined with cement kiln co-processing for fly ash disposal has been applied in China.After washing,the wastewater was evaporated to produce fly ash salt(FAS).In this study,FAS was mixed the KCl and LiCl to be used as molten chloride salt for energy storage material.Twenty-three types of molten salts with various ratios of FAS-KCl-LiCl were evaluated.Thermophysical properties(melting point and latent heat)and thermal stability of these salts were characterized.The increase in FAS fraction decreased the latent heat of molten salts.Among the tested samples,the best compatibility ratio of FAS:KCl:LiCl was 10:50:40(%,in weight),with latent heat of 108.7 J/g and melting point of 333℃.This molten salt also showed good thermal stability after 1–13 h of thermal experiments,and the mass loss was less than 2%after 5 heating cycles at 600℃.By corrosion test,FAS-KCl-LiCl(10:50:40,%in weight)could be more safely used in vessels made of nickel-based alloy,but it might cause corrosion risk for stainless steel.展开更多
Recycling rare earth elements(REEs)from waste is necessary for an environmentally sustainable reuse and wastewater management approach.Na-A zeolite was synthesized from coal fly ash(CFA)and applied for Ce^(3+)adsorpti...Recycling rare earth elements(REEs)from waste is necessary for an environmentally sustainable reuse and wastewater management approach.Na-A zeolite was synthesized from coal fly ash(CFA)and applied for Ce^(3+)adsorption.Fourier transform infrared(FTIR)spectra show peaks at 790,500 and 467 cm^(-1),which are bond vibrations of Si-O-Si,Si with Al-O and Si-O-.The surface area is 15.88 m^(2)/g,with a pore size of 2.14 nm.SEM images show a cubic shape,which indicates the formation of zeolite.Field emission and energy disperse spectroscopy(EDS)shows the formation of Si,Al,Na,and O.Na-A zeolite was applied for Ce^(3+)adsorption.The optimum conditions for Ce^(3+)adsorption are 50 ppm concentration,360 min,and pH 6.The maximum adsorption capacity is 176.49 mg/g.Based on the results,it is found that the adsorption of Ce^(3+)by Na-A zeolite is pseudo-second-order.The desorption test using HNO_(3) is more effective than using HCl and H_(2)SO_(4).A desorption efficiency of 97.22%is obtained at 4 cycles.Adsorption test using real sample wastewater demonstrates an adsorption efficiency of 83.35%.展开更多
Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly as...Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash paste.We conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the samples.The mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were investigated.The results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased significantly.When the content exceeded 4%,the rate of increase in strength decreased.Based on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping conditions.The activation effect was poor for long-term strength after 28 days.The CaO content did not significantly affect the degree of activation achieved.The maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the system.The activators also corroded the surface of the fly ash particles,resulting in a pozzolanic reaction.The active substances in fly ash were released efficiently,and hydration was realized.The pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.展开更多
In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive streng...In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive strength.In this study,505 groups of data were collected,and a new database of compressive strength of PFGC was constructed.In order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative analysis.The five machine learning models all showed good compressive strength prediction performance on PFGC.Among them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,respectively.While R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,respectively.The two models have high prediction accuracy and outstanding generalization ability.In order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 variables.These 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide dosage.Curing temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement concrete.The importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated mortality.Efficient therapeutic targets are beneficial to treat and predict the disease.Currently,the exact mo...BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated mortality.Efficient therapeutic targets are beneficial to treat and predict the disease.Currently,the exact molecular mechanisms leading to the progression of HCC are still unclear.Research has shown that the microRNA-142-3p level decreases in HCC,whereas bioinformatics analysis of the cancer genome atlas database shows the ASH1L expression increased among liver tumor tissues.In this paper,we will explore the effects and mechanisms of microRNA-142-3p and ASH1L affect the prognosis of HCC patients and HCC cell bioactivity,and the association between them.AIM To investigate the effects and mechanisms of microRNA-142-3p and ASH1L on the HCC cell bioactivity and prognosis of HCC patients.METHODS In this study,we grouped HCC patients according to their immunohistochemistry results of ASH1L with pathological tissues,and retrospectively analyzed the prognosis of HCC patients.Furthermore,explored the roles and mechanisms of microRNA-142-3p and ASH1L by cellular and animal experiments,which involved the following experimental methods:Immunohistochemical staining,western blot,quantitative real-time-polymerase chain reaction,flow cytometric analysis,tumor xenografts in nude mice,etc.The statistical methods involved in this study contained t-test,one-way analysis of variance,theχ^(2)test,the Kaplan-Meier approach and the log-rank test.RESULTS In this study,we found that HCC patients with high expression of ASH1L possess a more recurrence rate as well as a decreased overall survival rate.ASH1L promotes the tumorigenicity of HCC and microRNA-142-3p exhibits reduced expression in HCC tissues and interacts with ASH1L through targeting the ASH1L 3′untranslated region.Furthermore,microRNA-142-3p promotes apoptosis and inhibits proliferation,invasion,and migration of HCC cell lines in vitro via ASH1L.For the exploration mechanism,we found ASH1L may promote an immunosuppressive microenvironment in HCC and ASH1L affects the expression of the cell junction protein zonula occludens-1,which is potentially relevant to the immune system.CONCLUSION Loss function of microRNA-142-3p induces cancer progression and immune evasion through upregulation of ASH1L in HCC.Both microRNA-142-3p and ASH1L can feature as new biomarker for HCC in the future.展开更多
In order to adjust some properties of cement grout or concrete,some mineral admixtures are usually added in the preparation.Admixtures can reduce the cement consumption and save the cost,and also adjust the workabilit...In order to adjust some properties of cement grout or concrete,some mineral admixtures are usually added in the preparation.Admixtures can reduce the cement consumption and save the cost,and also adjust the workability of the material,improve the strength and durability of the cement stone,or reduce hydration heat of the composite cement.At present,the content of fly ash or slag is generally less than 50%among the composite cementitious materials that have been studied more,but there is little research on composite cementitious materials with large mineral admixture.In this paper,XRD,SEM,and adiabatic temperature rise tests were used to discuss hydration products and mechanism of composite cement grout with 90%content of fly ash and slag.The results show that the hydration of the composite cement grout is an alkali-activated hydration reaction,and the hydration products are mainly amorphous substances such as hydrated calcium silicate or hydrated calcium aluminate gel.The hydration reaction temperature rise is much lower than that of ordinary cement grout,and the time of the temperature peak is significantly delayed.展开更多
Microwave-curing and mechanical grinding of fly ash have both beenadopted as effective methods for improving the early-age strength of alkali-activated fly ash(AAFA)binders.This study combined these two approaches by ...Microwave-curing and mechanical grinding of fly ash have both beenadopted as effective methods for improving the early-age strength of alkali-activated fly ash(AAFA)binders.This study combined these two approaches by synthesizing AAFA using original,medium-fine,and ultrafine fly ash as precursors,and then specimens were cured with a five-stage temperature-controlled microwave.The compressive strength results indicate that the original AAFA develops the highest strength initially during microwave-curing,reaching 28 MPa at stage 2.Medium-fine AAFA exhibits the highest strength of 60 MPa when cured to stage 4-I,which is 26%higher than the peak strength of original AAFA.It is attributed to the significant rise in their specific surface area,which accelerates the dissolution of Si and Al from the precursor and facilitates the subsequent formation of N-A-S-H gels.Additionally,nanoscale zeolite crystals formed as secondary products fill the tiny gaps between amorphous products,thereby significantly improving their microstructure.In contrast,ultrafine fly ash,primarily composed of fragmented particles,necessitated a substantial amount of water,which adversely affects the absorption efficiency for microwave of AAFA specimens.Thus,ultrafine AAFA specimens consistently exhibit the lowest compressive strength.Specifically,at the end of curing,the compressive strength of these three specimens with microwave-curing is approximately 32%,59%,and 172%higher than that of the steam-cured sample,respectively.These findings demonstrate the compatibility of microwave-curing and fly ash refinement in enhancing the early compressive strength development of AAFA.展开更多
[Objectives]To explore the effects of mixed humus soil and straw ash substrate on rhizosphere bacterial community and growth of hot pepper.[Methods]In this pot experiment,high-throughput sequencing was conducted to an...[Objectives]To explore the effects of mixed humus soil and straw ash substrate on rhizosphere bacterial community and growth of hot pepper.[Methods]In this pot experiment,high-throughput sequencing was conducted to analyze bacterial communities in the rhizosphere soil of pepper plants treated with four different HA proportions.[Results]Pepper seedlings exhibited optimal growth in the 6:4(w/w)HA substrate.Bacterial structure and composition varied with the HA proportion.The relative abundance of the Proteobacteria phylum(ranging from 48.37%to 60.40%)was the highest across all treatments.Correlation analysis indicated that certain bacterial communities were closely related to the availability of soil nutrients and enzymatic activities.[Conclusions]This study elucidates the impact of HA proportion on rhizosphere bacterial communities and plant growth,laying a foundation for understanding the application of different mixed substrates and their effects on soil microbiology.展开更多
Municipal solid waste incineration fly ash(MSWI)is considered as one of the hazardous wastes and requires to be well disposed to reduce the contaminant to the environment.Reference to the production of coal fly ash(FA...Municipal solid waste incineration fly ash(MSWI)is considered as one of the hazardous wastes and requires to be well disposed to reduce the contaminant to the environment.Reference to the production of coal fly ash(FA)bricks,MSWI and FA were utilized to prepare autoclaved MSWI-FA block samples.Ultrasonic-assisted hydrothermal synthesis technology was used for production to explore the effect of ultrasonic pre-treatment.Compressive strength,dry density,and water absorption tests were conducted to determine the optimal ultrasonic parameters.Ultrasonic pre-treating mechanisms were investigated by SEM,FT-IR,particle size analysis,and BET.Furthermore,the micro-analyses of block samples were conducted.The heavy metal leaching concentration was studied to assess the environmental safety.The experimental results show that the ultrasonic pre-treating time,water bath temperature,and ultrasonic power of 3 h,30℃,and 840 W are the optimal,under which the compressive strength,dry density,and water absorption were 8.14 MPa,1417.48 kg/m^(3),and 0.38,respectively.It is shown that ultrasound destroys the surface structure of raw materials and smaller FA particles embed into MSWI.The particle size distribution of pre-treated raw materials mixture is wider and total pore volume is decreased by 6.3%.During hydrothermal processing,more Al-substituted tobermorite crystals are generated,which is the main source of higher strength and smaller pore volume of prepared block samples.The solidification/stabilization rates of Cu,Pb,and Zn increased by 30.77%,4.76%,and 35.29%,respectively.This study shows a feasible way to utilize MSWI as raw material for construction.展开更多
The thought of living near an active volcano probably sounds like an unimaginable experience-and rightly so.An active volcano can turn a forested hillside into a lifeless wasteland in seconds.From molten avalanches of...The thought of living near an active volcano probably sounds like an unimaginable experience-and rightly so.An active volcano can turn a forested hillside into a lifeless wasteland in seconds.From molten avalanches of rock to razor-sharp lung-shredding ash,volcanoes threaten people's lives and property.展开更多
Coke is the only solid charge component in the lower part of the blast furnace,and its strength is crucial to its production.Si and Al are the two most abundant elements in coke ash.The influences of these oxides on t...Coke is the only solid charge component in the lower part of the blast furnace,and its strength is crucial to its production.Si and Al are the two most abundant elements in coke ash.The influences of these oxides on the tensile strength of the coke matrix were studied by splitting tests.According to the Weibull analysis,with increasing Si and Al oxide concentrations,the fracture stress range of the coke widened,the upper and lower limits decreased,the probability of fracture under the same stress conditions increased,and the randomness and dispersion of strength increased.These results can be attributed to the inhibitory effect of ash during coal pyrolysis.Ash impedes the growth and contact of mesophase,leading to a decrease in graphitic carbon structures and an increase in edge carbon and aliphatic carbon structures in the resulting coke.Consequently,the overall ordering of the carbon structure is reduced.Moreover,SiO_(2)and Al_(2)O_(3)promoted the development of coke pores,thinned the coke pore wall,and significantly increased the proportion of large pores(>500μm).Moreover,Al_(2)O_(3)had more significant influences on the coke strength,carbon structure and stomatal ratio than SiO_(2).In addition,the position where the ash particles bonded to the carbon matrix easily produced cracks and holes,and the sharp edge of the matrix was likely to produce stress concentration points when subjected to an external force,leading to structural damage.Therefore,controlling the concentration of ash could effectively reduce the number of structural defects inside coke,which is conducive to improving the strength.展开更多
基金funded by the joint research collaboration of the Research Organization of Nanotechnology and Material,National Research and Innovation Agency(BRIN)(Grant number:8/HK/II/2024)with the title Organosolv Lignin-Based Hydrogels from Sugarcane Leaves and Their Potential as Wound Dressings with Widya Fatriasari as the Principal Investigatorthe Degree by Research(DBR)program of BRIN with scheme number:20/III.10/HK/2024 and scholarship number 4637/II.5.4/SI.06.01/7/2024 for Eko Budi Santoso。
文摘The significant amount of ash content in agricultural biomass presents an enormous challenge for efficient conversion processes.In addressing this issue,various deashing treatments have been tested and established,including simple leaching techniques,which can either be performed with or without the addition of chemical agents.These techniques hold promise for improving the deashing efficiency while potentially altering the structural and chemical composition of biomass,specifically lignin content,which is the key focus of this review.This review starts by exploring the presence of ash in agricultural residues and its impact on biomass properties.Next,this review examines deashing strategies aimed at reducing ash levels in biomass followed by analysis of the resulting changes in lignin physical and chemical properties as well as its thermal characteristics.The final part of this review is concluded by the discussion on the limitations of current approaches and the possible future directions to address the challenges covering the environmental impacts of the deashing treatments.A green process approach is emphasized as a sustainable solution with the aim to minimize negative environmental impacts associated with chemical usage during deashing.Finally,this review highlights the potential for ash recovery as a byproduct of the deashing processes,paving the way for an integrative,closed-loop approach within the biorefinery concept.
基金Funded by the National Natural Science Foundation of China(No.20806051)the Key Laboratory of Education Ministry for Solid Waste Management and Environment Safety(No.SWMES-2010-07)the Science and Technology Project of Housing and Urban-Rural Ministry(No.2010-K4-2)
文摘Production of glass-ceramics by sintering the molten slag obtained from electric arc furnace treatment of fly ash was investigated. The effect of washing pretreatment prior to melting the fly ash on the microstructure and properties of the glass-ceramics was examined. The results show that washing pretreatment of fly ash can decrease alkali metal chloride and increase network former in fly ash, which results in the increase of peak crystallization temperature of parent glass and strengthening of properties of bending strength and chemical stability of the glass-ceramics. The optimal heat treatment temperature for parent glass of washed fly ash is 1 173 K, at which the crystalline phase of glass-ceramics is composed of gelignite （Ca2A12SiO7） and akermanite （Ca2MgSi207）. Glass-ceramics produced at optimal heat treatment temperature are excellent in term of the physical and chemical properties and leaching characteristics, indicating attractive potential as substitute of nature materials.
文摘Dry ashing is an established method. Ashing whole blood samples are, however, often difficult to carry out with significant sample loss, and the procedure is not well documented. A new procedure has been devel- oped and optimized to dry-ash whole blood samples for trace metal analyses. The procedure reduces both the dry-ashing time by more than two thirds and sample loss. The ashed sample can be readily used in subse- quent, simultaneous or individual analysis of several metals by ICP-OES, as demonstrated in the analysis of a whole blood sample. The new procedure is simple, inexpensive, and faster than the established method.
文摘The coal filter cake is a product of fine coal after floatation which has an ash content of 7-13%, water content of 30±2%, and a particle size of less than 1 mm. The ash content was measured by the intensity of the single backscattered gamma-ray, and its accuracy is mainly dependent on the energy of the gamma-ray. The 238Pu low energy photon source is selected in this work. The energy of its gamma-ray is 15 keV, which can result not only in the best sensitivity, but also in the lowest contribution to the environment radiation. The root mean square deviation of the ash measurement is±0.33% (±1σ).
基金sponsored by Jiangsu Provincial Science and Technology Program Project(Nos.BE2022604 and BE2021701).
文摘Heavy metal stabilization and alkali neutralization are crucial for the management of municipal solid waste incineration fly ash(MSWI FA).In this study,the effects of oxalic acid(OA)and citric acid(CA)washing on heavy metal migration and alkali changes were investigated.Besides,three agents were selected to stabilize acid-washed fly ash(FA),and the effects of heavy metal stabilization under different disposal environments and the changes in their form distributions were comparatively analyzed.The experimental results demonstrated that with increasing organic acid concentration,the amount of Cd and Pb extracted from MSWI FA increased,whereas the amount of alkalis tended to decrease.Moreover,the leaching concentration of heavy metals and the percentage of unstable forms increased after acid washing.The alkalis content in the products decreased to 7.91-8.75 after stabilization,which met the standards of hazardous waste landfills.Compared with other agents,sodium diethyldithiocarbamate(DDTC)exhibited excellent heavy metal stabilization performance.After the addition of 1%DDTC,the leaching concentrations of Cd and Pb decreased to values lower than the national standard limit.Additionally,the curing rates of Cd and Pb were greater than 98%under the two leaching conditions.With the addition of DDTC,the percentage of stable forms increased,and the percentages of stable Cd and Pb forms increased to 87.68%and 99.03%,respectively,after treatment with 2%DDTC.The above results corroborated that CA coupled with DDTC stabilization can significantly reduce Cd and Pb toxicity and neutralize alkalinity in FA.
基金Project supported by the National Key Basic Research Program of China(Nos.2010CB934300,2013CBA01900,2011CBA00607,2011CB932804)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA09020402)+2 种基金the National Integrate Circuit Research Program of China(No.2009ZX02023-003)the National Natural Science Foundation of China(Nos.61176122,61106001,61261160500,61376006)the Science and Technology Council of Shanghai(Nos.12nm0503701,13DZ2295700,12QA1403900,13ZR 1447200)
文摘Phase change memory （PCM） has been regarded as a promising candidate for the next generation of nonvolatile memory. To decrease the power required to reset the PCM cell, titanium nitride （TIN） is preferred to be used as the bottom electrode of PCM due to its low thermal and suitable electrical conductivity. However, during the manufacture of PCM cell in 40 nm process node, abnormally high and discrete distribution of the resistance of TiN bottom electrode was found, which might be induced by the surface oxidation of TiN bottom electrode during the photoresist ashing process by oxygen plasma. In this work, we have studied the oxidation of TiN and found that with the increasing oxygen plasma ashing time, the thickness of the TiO2 layer became thicker and the state of the TiO2 layer changed from amorphous to crystalline, respectively. The resistance of TiN electrode contact chain with 4-5 nm TiO2 layer was confirmed to be almost three-orders of magnitude higher than that of pure TiN electrode, which led to the failure issue of PCM cell. We efficiently removed the oxidation TiO2 layer by a chemical mechanical polishing （CMP） process, and we eventually recovered the resistance of TiN bottom electrode from 1×10^5Ω/via back to 6×10^2 Ωvia and successfully achieved a uniform resistance distribution of the TiN bottom electrode.
基金Funded by Central Guiding Local Science and Technology Development Special Fund Project(No.ZYYD2023B02)Innovation and Entrepreneurship Training Program for College Students in Xinjiang Uygur Autonomous Region(No.S202410994015)+2 种基金China University of Mining and Technology Coal Fine Exploration and Intelligent Development National Key Laboratory Xinjiang Engineering College Joint Fund(No.SKLCRSM-XJIE24KF001)Basic Research Funds for Autonomous Region Universities(No.XJEDU2024P082)National Natural Science Foundation of China(No.41662017)。
文摘In order to realize the comprehensive utilization of industrial solid waste rice husk ash and heavy metal cadmium contaminated soil,rice husk ash-based geopolymer prepared by alkaline activator was used to modify cadmium contaminated soil.The main physical and chemical properties of rice husk ash were clarified by SEM,XRF and X-ray diffraction.The unconfined compressive strength test and toxicity leaching test were carried out on the modified soil.Combined with FTIR and TG micro-level,the solidification mechanism of rice husk ash-based geopolymer solidified cadmium contaminated soil was discussed.The results show that the strength of geopolymer modified soil is significantly higher than that of plain soil,and the unconfined compressive strength at 7 d age is 4.2 times that of plain soil.The strength of modified soil with different dosage of geopolymer at 28 d age is about 36% to 40% higher than that of modified soil at 7 d age.Geopolymer has a significant effect on the leaching of heavy metals in contaminated soil.When the cadmium content is 100 mg/kg,it meets the standard limit.In the process of complex depolymerization-condensation reaction,on the one hand,geopolymers are cemented and agglomerated to form a complex spatial structure,which affects the macro and micro characteristics of soil.On the other hand,it has significant adsorption,precipitation and replacement effects on heavy metal ions in soil,showing good strength and low heavy metal leaching toxicity.
基金support from the International Cooperation Project of Zhejiang Province(No.2019C04026)National Natural Science Foundation,China(No.51976196).
文摘Fly ash,as a byproduct of municipal solid waste incineration,contains several kinds of pollutants,especially dissolvable salts that cause a severe challenge for fly ash disposal.Washing combined with cement kiln co-processing for fly ash disposal has been applied in China.After washing,the wastewater was evaporated to produce fly ash salt(FAS).In this study,FAS was mixed the KCl and LiCl to be used as molten chloride salt for energy storage material.Twenty-three types of molten salts with various ratios of FAS-KCl-LiCl were evaluated.Thermophysical properties(melting point and latent heat)and thermal stability of these salts were characterized.The increase in FAS fraction decreased the latent heat of molten salts.Among the tested samples,the best compatibility ratio of FAS:KCl:LiCl was 10:50:40(%,in weight),with latent heat of 108.7 J/g and melting point of 333℃.This molten salt also showed good thermal stability after 1–13 h of thermal experiments,and the mass loss was less than 2%after 5 heating cycles at 600℃.By corrosion test,FAS-KCl-LiCl(10:50:40,%in weight)could be more safely used in vessels made of nickel-based alloy,but it might cause corrosion risk for stainless steel.
基金Project supported by Rumah Program 2023 and Net Zero Emission Program(1507/Ⅱ.7/HK.01.00/6/2023)a research facility from the National Research and Innovation Agency of Republic of Indonesia。
文摘Recycling rare earth elements(REEs)from waste is necessary for an environmentally sustainable reuse and wastewater management approach.Na-A zeolite was synthesized from coal fly ash(CFA)and applied for Ce^(3+)adsorption.Fourier transform infrared(FTIR)spectra show peaks at 790,500 and 467 cm^(-1),which are bond vibrations of Si-O-Si,Si with Al-O and Si-O-.The surface area is 15.88 m^(2)/g,with a pore size of 2.14 nm.SEM images show a cubic shape,which indicates the formation of zeolite.Field emission and energy disperse spectroscopy(EDS)shows the formation of Si,Al,Na,and O.Na-A zeolite was applied for Ce^(3+)adsorption.The optimum conditions for Ce^(3+)adsorption are 50 ppm concentration,360 min,and pH 6.The maximum adsorption capacity is 176.49 mg/g.Based on the results,it is found that the adsorption of Ce^(3+)by Na-A zeolite is pseudo-second-order.The desorption test using HNO_(3) is more effective than using HCl and H_(2)SO_(4).A desorption efficiency of 97.22%is obtained at 4 cycles.Adsorption test using real sample wastewater demonstrates an adsorption efficiency of 83.35%.
基金Supported by Yunnan Major Scientific and Technological Projects(No.202403AA080001)National Natural Science Foundation of China(No.52074137)Yunnan Fundamental Research Projects(No.202201AT070151)。
文摘Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash paste.We conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the samples.The mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were investigated.The results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased significantly.When the content exceeded 4%,the rate of increase in strength decreased.Based on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping conditions.The activation effect was poor for long-term strength after 28 days.The CaO content did not significantly affect the degree of activation achieved.The maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the system.The activators also corroded the surface of the fly ash particles,resulting in a pozzolanic reaction.The active substances in fly ash were released efficiently,and hydration was realized.The pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.
基金Funded by the Natural Science Foundation of China(No.52109168)。
文摘In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive strength.In this study,505 groups of data were collected,and a new database of compressive strength of PFGC was constructed.In order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative analysis.The five machine learning models all showed good compressive strength prediction performance on PFGC.Among them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,respectively.While R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,respectively.The two models have high prediction accuracy and outstanding generalization ability.In order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 variables.These 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide dosage.Curing temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement concrete.The importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.
基金Supported by the Haihe Laboratory of Cell Ecosystem Innovation Fund,No.22HHXBJC00001the Key Discipline Special Project of Tianjin Municipal Health Commission,No.TJWJ2022XK016.
文摘BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated mortality.Efficient therapeutic targets are beneficial to treat and predict the disease.Currently,the exact molecular mechanisms leading to the progression of HCC are still unclear.Research has shown that the microRNA-142-3p level decreases in HCC,whereas bioinformatics analysis of the cancer genome atlas database shows the ASH1L expression increased among liver tumor tissues.In this paper,we will explore the effects and mechanisms of microRNA-142-3p and ASH1L affect the prognosis of HCC patients and HCC cell bioactivity,and the association between them.AIM To investigate the effects and mechanisms of microRNA-142-3p and ASH1L on the HCC cell bioactivity and prognosis of HCC patients.METHODS In this study,we grouped HCC patients according to their immunohistochemistry results of ASH1L with pathological tissues,and retrospectively analyzed the prognosis of HCC patients.Furthermore,explored the roles and mechanisms of microRNA-142-3p and ASH1L by cellular and animal experiments,which involved the following experimental methods:Immunohistochemical staining,western blot,quantitative real-time-polymerase chain reaction,flow cytometric analysis,tumor xenografts in nude mice,etc.The statistical methods involved in this study contained t-test,one-way analysis of variance,theχ^(2)test,the Kaplan-Meier approach and the log-rank test.RESULTS In this study,we found that HCC patients with high expression of ASH1L possess a more recurrence rate as well as a decreased overall survival rate.ASH1L promotes the tumorigenicity of HCC and microRNA-142-3p exhibits reduced expression in HCC tissues and interacts with ASH1L through targeting the ASH1L 3′untranslated region.Furthermore,microRNA-142-3p promotes apoptosis and inhibits proliferation,invasion,and migration of HCC cell lines in vitro via ASH1L.For the exploration mechanism,we found ASH1L may promote an immunosuppressive microenvironment in HCC and ASH1L affects the expression of the cell junction protein zonula occludens-1,which is potentially relevant to the immune system.CONCLUSION Loss function of microRNA-142-3p induces cancer progression and immune evasion through upregulation of ASH1L in HCC.Both microRNA-142-3p and ASH1L can feature as new biomarker for HCC in the future.
文摘In order to adjust some properties of cement grout or concrete,some mineral admixtures are usually added in the preparation.Admixtures can reduce the cement consumption and save the cost,and also adjust the workability of the material,improve the strength and durability of the cement stone,or reduce hydration heat of the composite cement.At present,the content of fly ash or slag is generally less than 50%among the composite cementitious materials that have been studied more,but there is little research on composite cementitious materials with large mineral admixture.In this paper,XRD,SEM,and adiabatic temperature rise tests were used to discuss hydration products and mechanism of composite cement grout with 90%content of fly ash and slag.The results show that the hydration of the composite cement grout is an alkali-activated hydration reaction,and the hydration products are mainly amorphous substances such as hydrated calcium silicate or hydrated calcium aluminate gel.The hydration reaction temperature rise is much lower than that of ordinary cement grout,and the time of the temperature peak is significantly delayed.
文摘Microwave-curing and mechanical grinding of fly ash have both beenadopted as effective methods for improving the early-age strength of alkali-activated fly ash(AAFA)binders.This study combined these two approaches by synthesizing AAFA using original,medium-fine,and ultrafine fly ash as precursors,and then specimens were cured with a five-stage temperature-controlled microwave.The compressive strength results indicate that the original AAFA develops the highest strength initially during microwave-curing,reaching 28 MPa at stage 2.Medium-fine AAFA exhibits the highest strength of 60 MPa when cured to stage 4-I,which is 26%higher than the peak strength of original AAFA.It is attributed to the significant rise in their specific surface area,which accelerates the dissolution of Si and Al from the precursor and facilitates the subsequent formation of N-A-S-H gels.Additionally,nanoscale zeolite crystals formed as secondary products fill the tiny gaps between amorphous products,thereby significantly improving their microstructure.In contrast,ultrafine fly ash,primarily composed of fragmented particles,necessitated a substantial amount of water,which adversely affects the absorption efficiency for microwave of AAFA specimens.Thus,ultrafine AAFA specimens consistently exhibit the lowest compressive strength.Specifically,at the end of curing,the compressive strength of these three specimens with microwave-curing is approximately 32%,59%,and 172%higher than that of the steam-cured sample,respectively.These findings demonstrate the compatibility of microwave-curing and fly ash refinement in enhancing the early compressive strength development of AAFA.
文摘[Objectives]To explore the effects of mixed humus soil and straw ash substrate on rhizosphere bacterial community and growth of hot pepper.[Methods]In this pot experiment,high-throughput sequencing was conducted to analyze bacterial communities in the rhizosphere soil of pepper plants treated with four different HA proportions.[Results]Pepper seedlings exhibited optimal growth in the 6:4(w/w)HA substrate.Bacterial structure and composition varied with the HA proportion.The relative abundance of the Proteobacteria phylum(ranging from 48.37%to 60.40%)was the highest across all treatments.Correlation analysis indicated that certain bacterial communities were closely related to the availability of soil nutrients and enzymatic activities.[Conclusions]This study elucidates the impact of HA proportion on rhizosphere bacterial communities and plant growth,laying a foundation for understanding the application of different mixed substrates and their effects on soil microbiology.
基金Funded by the National Natural Science Foundation of China(No.52178241)the National Key Research and Development Program of China during the Fourteenth Five-Year Plan Period(No.2021YFB3802001)+1 种基金the Shanghai Science and Technology Innovation Action Plan(No.23D21201401)the Key Research and Development of the Shaanxi Province of China(No.2022GY-163)。
文摘Municipal solid waste incineration fly ash(MSWI)is considered as one of the hazardous wastes and requires to be well disposed to reduce the contaminant to the environment.Reference to the production of coal fly ash(FA)bricks,MSWI and FA were utilized to prepare autoclaved MSWI-FA block samples.Ultrasonic-assisted hydrothermal synthesis technology was used for production to explore the effect of ultrasonic pre-treatment.Compressive strength,dry density,and water absorption tests were conducted to determine the optimal ultrasonic parameters.Ultrasonic pre-treating mechanisms were investigated by SEM,FT-IR,particle size analysis,and BET.Furthermore,the micro-analyses of block samples were conducted.The heavy metal leaching concentration was studied to assess the environmental safety.The experimental results show that the ultrasonic pre-treating time,water bath temperature,and ultrasonic power of 3 h,30℃,and 840 W are the optimal,under which the compressive strength,dry density,and water absorption were 8.14 MPa,1417.48 kg/m^(3),and 0.38,respectively.It is shown that ultrasound destroys the surface structure of raw materials and smaller FA particles embed into MSWI.The particle size distribution of pre-treated raw materials mixture is wider and total pore volume is decreased by 6.3%.During hydrothermal processing,more Al-substituted tobermorite crystals are generated,which is the main source of higher strength and smaller pore volume of prepared block samples.The solidification/stabilization rates of Cu,Pb,and Zn increased by 30.77%,4.76%,and 35.29%,respectively.This study shows a feasible way to utilize MSWI as raw material for construction.
文摘The thought of living near an active volcano probably sounds like an unimaginable experience-and rightly so.An active volcano can turn a forested hillside into a lifeless wasteland in seconds.From molten avalanches of rock to razor-sharp lung-shredding ash,volcanoes threaten people's lives and property.
基金supported by the National Natural Science Foundation of China(No.51974212)the China Baowu Low Carbon Metallurgy Innovation Foundation(No.BWLCF202116)+2 种基金the Science and Technology Major Project of Wuhan(No.2023020302020572)the Postdoctor Project of Hubei Province(No.2024HBBHCXA074)the Foundation of Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education(No.FMRUlab23-04).
文摘Coke is the only solid charge component in the lower part of the blast furnace,and its strength is crucial to its production.Si and Al are the two most abundant elements in coke ash.The influences of these oxides on the tensile strength of the coke matrix were studied by splitting tests.According to the Weibull analysis,with increasing Si and Al oxide concentrations,the fracture stress range of the coke widened,the upper and lower limits decreased,the probability of fracture under the same stress conditions increased,and the randomness and dispersion of strength increased.These results can be attributed to the inhibitory effect of ash during coal pyrolysis.Ash impedes the growth and contact of mesophase,leading to a decrease in graphitic carbon structures and an increase in edge carbon and aliphatic carbon structures in the resulting coke.Consequently,the overall ordering of the carbon structure is reduced.Moreover,SiO_(2)and Al_(2)O_(3)promoted the development of coke pores,thinned the coke pore wall,and significantly increased the proportion of large pores(>500μm).Moreover,Al_(2)O_(3)had more significant influences on the coke strength,carbon structure and stomatal ratio than SiO_(2).In addition,the position where the ash particles bonded to the carbon matrix easily produced cracks and holes,and the sharp edge of the matrix was likely to produce stress concentration points when subjected to an external force,leading to structural damage.Therefore,controlling the concentration of ash could effectively reduce the number of structural defects inside coke,which is conducive to improving the strength.
