Lead fuming furnace slag(LFFS)is a by-product of lead metal production,which is a toxic solid waste according to toxicity characteristic leaching procedure(TCLP)*** was investigated the feasibility of preparation of g...
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Lead fuming furnace slag(LFFS)is a by-product of lead metal production,which is a toxic solid waste according to toxicity characteristic leaching procedure(TCLP)*** was investigated the feasibility of preparation of geopolymer using coal fly ash(CFA)and LFFS and the immobilization efficiency of Cd in *** synthesized geopolymer samples were examined by compressive strength,Fourier transform transmission infrared spectroscopy(FTIR)spectra,X-ray diffraction(XRD)and backscattered electron(BSE)*** is a certain mass ratio(2:3)of the LFFS to the CFA at which the compressive strength of the geopolymeric matrix is the *** test shows that Cd in LFFS can be effectively immobilized in the geopolymer *** is not only a potential technological solution for reusing LFFS but also an effective immobilization method for LFFS treatment and disposal.
Al-Mg-Si alloys with high strength and good corrosion resistance are regarded as desirable materials for all-aluminum ***,the traditional trial-and-error experimental methods are insufficient to address the trade-offb...
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Al-Mg-Si alloys with high strength and good corrosion resistance are regarded as desirable materials for all-aluminum ***,the traditional trial-and-error experimental methods are insufficient to address the trade-offbetween strength and corrosion *** this work,a non-dominated sorting genetic machine-learning algorithm(NSGA-II)was employed to optimize the chemical composition,so as to simultaneously improve the strength and corrosion *** high-performance Al-Mg-Si alloys with low Mg,Si,and Cu contents were successfully developed,where the yield strength(YS),ultimate tensile strength(UTS),and the elongation(δ)reached 375-380 MPa,410-416 MPa,and 13.7%-15.2%,*** with higher-Cu-content 6013 alloy,the YS and UTS of the present alloys increase by about 60 MPa,and the intergranular corrosion resistance is also significantly ***-ture characterization demonstrated thatβ’’and QP phases introduced a significant synergistic precipita-tion strengthening effect;the dispersoids formed by trace Mn,Cr,Fe,Zr,and Ti contributed dispersion strengthening effect;and the good pitting corrosion resistance is attributed to lower Mg and Si contents.
Fibrous porous ceramics are attractive for use as thermal insulation ***,the intrinsic brit-tleness of rigid materials has remained challenging and severely restricts their ***,we demonstrated a facile method for fabr...
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Fibrous porous ceramics are attractive for use as thermal insulation ***,the intrinsic brit-tleness of rigid materials has remained challenging and severely restricts their ***,we demonstrated a facile method for fabricating elastic fibrous porous ceramics(EFPCs)with high com-pressive strength and low thermal conductivity through ordinary press filtration and subsequent heat *** quasi-layered structure and the well-bonded bridging fibers between layers are the key points for the elasticity of *** advanced EFPCs exhibited low density(∼0.126 g cm^(−3)),high com-pressive stress(∼0.356 MPa),and low thermal conductivity(∼0.026 W m^(−1) K^(−1)).Compared with rigid porous fibrous materials,the EFPCs had deformability and excellent shape *** contrast to flexible materials,the EFPCs possessed high compressive stress,thus endowing them with good resistance to *** emergence of this fascinating material may provide new insights for candidate materials in thermal insulation and other fields.
Transition metal disilicides are widely used as heating elements and infrared emission ***,the limited intrinsic infrared emissivity and high thermal conductivity are the main limitations to their applications as infr...
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Transition metal disilicides are widely used as heating elements and infrared emission ***,the limited intrinsic infrared emissivity and high thermal conductivity are the main limitations to their applications as infrared emission coatings in the thermal protection *** cope with these prob-lems,four medium and high-entropy transition metal disilicides,i.e.,(V_(0.25)Ta_(0.25)Mo_(0.25)W_(0.25))Si_(2)(ME-1),(Nb_(0.25)Ta_(0.25)Mo_(0.25)W_(0.25))Si_(2)(ME-2),(V_(0.2)Nb_(0.2)Ta_(0.2)Mo_(0.2)W_(0.2))Si_(2)(HE-1),and(Cr_(0.2)Nb_(0.2)Ta_(0.2)Mo_(0.2)W_(0.2))Si_(2)(HE-2),were designed and synthesized by spark plasma sintering method using transition metal binary disilicides as *** introduction of multi-elements into transition metal disilicides not only im-proved the infrared emissivity but also reduced the electrical and thermal *** them,(Cr_(0.2)Nb_(0.2)Ta_(0.2)Mo_(0.2)W_(0.2))Si_(2)(HE-2)had the lowest electrical conductivity of 3789 S cm-1,which is over one order of magnitude lower than that of MoSi_(2)(50000 S cm^(-1)),and total infrared emissivity of 0.42 at room temperature,which is nearly double of that of TaSi_(2).Benefiting from low electrical conductivity and phonon scattering due to lattice distortion,the medium and high-entropy transition metal disilicides also demonstrated a significant decline in thermal conductivity compared to their binary *** all samples,HE-2 exhibited the lowest thermal conductivity of 6.4 W m^(−1)K^(−1).The high-entropy tran-sition metal disilicides also present excellent oxidation resistance at high *** improved infrared emissivity,reduced thermal conductivity,excellent oxidation resistance,and lower densities of these medium and high-entropy transition metal disilicides portend that they are promising as infrared emission coating materials for applications in thermal protection systems.
Here we propose to employ wire-arc directed energy deposition(WA-DED) to tune the microstructure and the mechanical property of Mg-Al-Si alloys, on the basis of its sub-rapid solidification effect. According to finite...
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Here we propose to employ wire-arc directed energy deposition(WA-DED) to tune the microstructure and the mechanical property of Mg-Al-Si alloys, on the basis of its sub-rapid solidification effect. According to finite element analysis, WA-DED shows higher cooling rate than conventional casting, reaching 598.3 K/s for Mg-Al-Si alloy, and the lower heat input, the larger cooling rate of WA-DED. Significant microstructure refinement is thus achieved, with reduced grain size and Mg_(2)Si particle diameter. The transition from hypereutectic to fully eutectic microstructure is triggered by reducing the heat input. Compared with the as-cast alloy, WA-DED alloys demonstrate higher ultimate tensile strengths(UTS) at both room-and high-temperature(150℃) properties, increasing by 50.1% and 30.3%, respectively. The superior strength-ductility synergy for Mg-Al-Si alloys results from the microstructure tuning via sub-rapid solidification of WA-DED.
This paper introduces a different perspective of Neutrosophic Fractals and Neutrosophic Soft Fractals, merging the principles of Neutrosophic Logic, Soft set theory, and Fractal Geometry to address indeterminacy in co...
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The long-lasting expectation"the hotter the engine,the better"calls for the development of high-temperature metallic *** the high specific strengths of titanium alloys are compelling for such applications,th...
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The long-lasting expectation"the hotter the engine,the better"calls for the development of high-temperature metallic *** the high specific strengths of titanium alloys are compelling for such applications,their deleterious softening beyond 600 ℃ imposes serious *** has been known for decades regarding the phase metallurgy for precipitation strengthening design in titanium al-loys,however,the other facile strength promotion mechanism,dispersion strengthening,remains compar-atively less-explored and *** present research concerns the multi-scale dispersion strength-ening in titanium alloys,with mechanistic emphases on the critical plasticity micro-events that affect strength *** to the simultaneous introduction of intragranular dispersoids and intergran-ular reinforcers,the current titanium alloys present superior engineering tensile strength of 519 MPa at 700 ℃.Throughout the examined 25-800 ℃ temperature range,noticeable softening induced by the ther-mal activation occurs above 600 ℃,accompanied by evident strength *** temperature-dependence transition of dominated softening mechanisms from dynamic recovery to dynamic recrystallization has been clarified by theoretical ***,the strengthening effect of multi-scale architec-tures is underpinned as the enhanced dislocation strengthening owing to the introduction of thermally-stable heterointerfaces,which could generically guide the design of similar heat-resistant titanium alloys.
Dear Editor,H∞This letter develops a new framework for the robust stability and performance conditions as well as the relevant controller synthesis with respect to uncertain robot *** often exist model uncertainties ...
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Dear Editor,H∞This letter develops a new framework for the robust stability and performance conditions as well as the relevant controller synthesis with respect to uncertain robot *** often exist model uncertainties between the nominal model and the real robot manipulator and disturbances. Hence, dealing with their effects plays a crucial role in leading to high tracking performances, as discussed in [1]–[5].
The shift towards sustainable energy requires efficient electrochemical conversion technologies,emphasizing the crucial need for robust electrocatalyst design. Recent findings reveal that the efficiency of some electr...
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The shift towards sustainable energy requires efficient electrochemical conversion technologies,emphasizing the crucial need for robust electrocatalyst design. Recent findings reveal that the efficiency of some electrocatalytic reactions is spin-dependent, with spin configuration dictating ***, understanding the spin's role and controlling it in electrocatalysts is important. This review succinctly outlines recent investigations into spin-dependent electrocatalysis, stressing its importance in energy conversion. It begins with an introduction to spin-related features, discusses characterization techniques for identifying spin configurations, and explores strategies for fine-tuning them. At the end, the article provides insights into future research directions, aiming to reveal more unknown fundamentals of spin-dependent electrocatalysis and encourage further exploration in spin-related research and applications.
The martensitic transformation temperature is the basis for the application of shape memory alloys(SMAs),and the ability to quickly and accurately predict the transformation temperature of SMAs has very important prac...
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The martensitic transformation temperature is the basis for the application of shape memory alloys(SMAs),and the ability to quickly and accurately predict the transformation temperature of SMAs has very important practical *** this work,machine learning(ML)methods were utilized to accelerate the search for shape memory alloys with targeted properties(phase transition temperature).A group of component data was selected to design shape memory alloys using reverse design method from numerous unexplored *** modeling and feature modeling were used to predict the phase transition temperature of the shape memory *** experimental results of the shape memory alloys were obtained to verify the effectiveness of the support vector regression(SVR)*** results show that the machine learning model can obtain target materials more efficiently and pertinently,and realize the accurate and rapid design of shape memory alloys with specific target phase transition *** this basis,the relationship between phase transition temperature and material descriptors is analyzed,and it is proved that the key factors affecting the phase transition temperature of shape memory alloys are based on the strength of the bond energy between *** work provides new ideas for the controllable design and performance optimization of Cu-based shape memory alloys.
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