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Amphoteric oxides (Al 2 O 3 and B 2 O 3) represent opposite effects on the structure and properties of silicate melts in different conditions, while the understanding about the transition from acidity to basicity is far from complete. Molecular dynamics simulation was adopted in the present study to investigate the performance and acidity-basicity transformation of Al 2 O 3 and B 2 O 3 in the SiO 2 –CaO–Al 2 O 3 –B 2 O 3 system. The results showed that, different from Ca2+ ions, excessive Al3+ or B3+ ions tend to destroy the bridge oxygen structures, showing the function of basic oxide. This is similar to the behavior of Ca2+ ions and other basicity ions. It was found that, on the one hand, B3+ ions tend to form [BO 3 ]3- planar triangular structures with the increase of B3+ ions contents, on the other hand, B3+ ions could reduce the stability of Si–O bonds. Therefore, B3+ ions could make the system structure less stable, which is the reason why the B 2 O 3 is a kind of active agent. In addition, because of the significant differences in lattice energy and atomic structure between Al 2 O 3 and B 2 O 3 , the effects of Al 2 O 3 and B 2 O 3 on the thermodynamic properties of silicate melts are quite different. [ABSTRACT FROM AUTHOR]

Molten slag has different properties depending on its composition. The relationship between its composition, structure, and properties has been the focus of attention in industrial manufacturing processes. This review describes the atomistic scale mechanisms by which oxides of different compositions affect the properties and structure of slag, and depicts the current state of research in the atomic simulation of molten slag. At present, the research on the macroscopic properties of molten slag mainly focuses on viscosity, free-running temperature, melting point, and desulphurization capacity. Regulating the composition has become the most direct and effective way to control slag properties. Analysis of the microevolution mechanism is the fundamental way to grasp the macroscopic properties. The microstructural evolution mechanism, especially at the atomic and nanoscale of molten slag, is reviewed from three aspects: basic oxides, acidic oxides, and amphoteric oxides. The evolution of macroscopic properties is analyzed in depth through the evolution of the atomic structure. Resolution of the macroscopic properties of molten slag by the atomic structure plays a crucial role in the development of fundamental theories of physicochemistry. [ABSTRACT FROM AUTHOR]

• The Al 2 O 3 (B 2 O 3)-bearing melts structure was studied by molecular dynamics. • Amphoteric oxides Al 2 O 3 (B 2 O 3) gradually appear basic. • Basic Al 2 O 3 (B 2 O 3) will reduce the bridging oxygen content of the system. • Al 2 O 3 increases the viscosity of systems, while using B 2 O 3 the opposite occurs. Al 2 O 3 and B 2 O 3 possess properties of amphoteric oxide, so Al 2 O 3 and B 2 O 3 have many different influences on the structure and properties of silicate melts, while its influence mechanism in atomic scale has not yet been fully understood. Molecular dynamics (MD) simulation was conducted to gain a clear understanding about the influences of Al 2 O 3 and B 2 O 3 on the structure and properties of SiO 2 -CaO-Al 2 O 3 (SiO 2 -CaO-B 2 O 3) silicate melts at 1773 K. The results show that when the Al 2 O 3 content is less than 25 wt.%, the Al 2 O 3 in the system is almost acidic in the studied system, and the bridging oxygen content and polymerization degree of the system increase with the increase of Al 2 O 3 content. When the content of Al 2 O 3 exceeds 25 wt.%, part of Al 2 O 3 in the system becomes basic, which makes the bridging oxygen content of the system decrease and the growth rate of polymerization degree decrease. The effect of B 2 O 3 on the network structure of SiO 2 -CaO-B 2 O 3 (SCB) system is similar to that of Al 2 O 3 in SiO 2 -CaO-Al 2 O 3 (SCA) system, but the inflection point from acid to basic is lower (21 wt.%) and the basicity is stronger. Moreover, through two suitable viscosity calculation models, combined with experimental data, it shows that the viscosity of SCA system increases with the increase of Al 2 O 3 content, while that of SCB system is just the opposite. [ABSTRACT FROM AUTHOR]

• The B 2 O 3 -bearing slag structure was investigated with molecular dynamics. • Boron was found to form planar triangular structure with oxygen. • B 2 O 3 increase polymerization degree by increasing bridge oxygen content. • B 2 O 3 decrease slag viscosity by decreasing the stability of network structure. B 2 O 3 has the advantages of reducing the liquidus temperature and enhancing the fluidity of slag, while its influence mechanism in atomic scale has not yet been fully understood. Molecular dynamics simulation was conducted to investigate the influence of B 2 O 3 on the structure and properties of SiO 2 CaO-Al 2 O 3 -B 2 O 3 blast furnace slag system at 1773 K. Results showed that a large number of [SiO 4 ]4−-[BO 3 ]3− structures are generated in the system after B 2 O 3 added, Si4+ ions mainly exist in the form of [SiO 4 ]4- tetrahedrons and B3+ ions mainly exist in the form of [BO 3 ]3− planar triangular structures and [BO 4 ]5− tetrahedrons. With the increase of B 2 O 3 content, the proportion of [BO 3 ]3− planar triangular structures increase. In addition, the content of bridge oxygen in the microstructure of slag increases obviously, the content of non-bridge oxygen decreases, and the polymerization degree of the system increases somewhat. Through the analysis of microscopic mechanism and the modified NPL viscosity model, combined with experimental data, the truth that the slag viscosity decreases with the increase of B 2 O 3 contents were known in the simulated concentration range. [ABSTRACT FROM AUTHOR]

Objective: Acute kidney injury (AKI) is a clinical syndrome that occurs as a result of a dramatic decline in kidney function caused by a variety of etiological factors. Its main biomarkers, serum creatinine and urine output, are not effective in diagnosing early AKI. For this reason, this study provides insight into this syndrome by exploring the comorbidities of AKI, which may facilitate the early diagnosis of AKI. In addition, organ crosstalk in AKI was systematically explored based on comorbidities to obtain clinically reliable results. Methods: We collected data from the Medical Information Mart for Intensive Care-IV database on patients aged ≥ 18 years in intensive care units (ICU) who were diagnosed with AKI using the criteria proposed by Kidney Disease: Improving Global Outcomes. The Apriori algorithm was used to mine association rules on the diagnoses of 55,486 AKI and non-AKI patients in the ICU. The comorbidities of AKI mined were validated through the Electronic Intensive Care Unit database, the Colombian Open Health Database, and medical literature, after which comorbidity results were visualized using a disease network. Finally, organ diseases were identified and classified from comorbidities to investigate renal crosstalk with other distant organs in AKI. Results: We found 579 AKI comorbidities, and the main ones were disorders of lipoprotein metabolism, essential hypertension, and disorders of fluid, electrolyte, and acid-base balance. Of the 579 comorbidities, 554 were verifiable and 25 were new and not previously reported. In addition, crosstalk between the kidneys and distant non-renal organs including the liver, heart, brain, lungs, and gut was observed in AKI with the strongest heart-kidney crosstalk, followed by lung-kidney crosstalk. Conclusion: The comorbidities mined in this study using association rules are scientific and may be used for the early diagnosis of AKI and the construction of AKI predictive models. Furthermore, the organ crosstalk results obtained through comorbidities may provide supporting information for the management of short- and long-term treatment practices for organ dysfunction. [ABSTRACT FROM AUTHOR]

The shape of shaft furnace is a crucial feature of direct reduction processes, as it affects both particle and gas flow during production. However, current knowledge on the impact of furnace shape on particle flow is limited. Herein, the discrete element method is employed for numerical simulations, in which two different methods of varying the wall angle (i.e., changing the radius or the height) are utilized to investigate the effect of wall angle on the flow behavior of particles in a shaft furnace. The effect of wall angle under different combinations of radius and height on the transformation of the particle flow pattern is innovatively examined, compared to previous studies on charging particles and internal furnace conditions. It is demonstrated in the results that the wall angle of the shaft furnace has a significant influence on the transformation of particle flow mode, with a reduction in the wall angle facilitating the transformation of particle flow mode to mass flow. Furthermore, it is shown in the study that different methods of changing the wall angle have varying effects on the transformation of particle flow mode. [ABSTRACT FROM AUTHOR]

In recent years, with the attention given to hydrogen reduction‐related technologies, the parameter indicators of direct reduction in the shaft furnace have gained importance. Herein, the numerical simulation of the particle flow field in the shaft furnace is investigated with the help of discrete element method (DEM) model. In contrast to the subregional modeling and the single particle shape study of the previous studies, this study innovatively uses the real shape of the particles and the overall structure of the vertical furnace for modeling. The transient characteristics of solid particle flow under ten lump ore ratios and three shapes are considered. The results show that the mass fraction and the shape of lump ore have little effect on the particle falling speed, but have a significant effect on the particle segregation behavior. In addition, the void ratio responds to the permeability condition in the furnace, which is also influenced by the lump ore proportion and shape. [ABSTRACT FROM AUTHOR]

[Display omitted] • Uses frontier molecular orbital energies as the source domain in transfer learning. • Utilizes reorganization energies as the target domain, minimizing data required. • Effective at predicting low reorganization energies. • Provides a convenient method for studying compound reorganization energies. • Accelerates research on material optical properties using this method. Reorganization energy, a crucial factor in quantum chemistry, plays an integral role in the research of optoelectronic and electrical devices such as organic field-effect transistors and organic light-emitting diodes. Currently, the calculation of reorganization energy predominantly depends on density functional theory, which poses significant computational costs. Traditional machine learning, commonly employed to predict reorganization energy necessitates a substantial volume of data for model training, a process that can be time-consuming due to difficulties in collecting sufficient data. This study proposes a novel solution by employing transfer learning. This method involves the pre-trained model using publicly accessible large-scale data on frontier molecular orbital energy, and then transfers this model to predict the reorganization energy. The experimental results indicate that the proposed method requires approximately 28% less data compared to traditional machine learning while maintaining equivalent accuracy. Moreover, this method achieved a median error of less than 0.02 eV when predicting low reorganization energy. Consequently, the need for reorganization energy data in model construction is significantly reduced, thus facilitating research into reorganization energy and expediting research into the optical properties of materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • In-depth atomic scale investigations of graphene gasification with O 2 , H 2 O and CO 2. • Differences in kinetics and atomic behavior of the three oxidants were observed. • Significant out-of-plane activity was noted in the case of H 2 O oxidant. • The oxidation with CO 2 and H 2 O may not be occurring on the same active sites. Fundamental understanding of the oxidation behavior of O 2 , H 2 O, and CO 2 in the process of oxyfuel combustion is of great significance. Extensive MD simulations with reactive force-field (ReaxFF) were performed to compare the gasification behavior under the individual influence of three oxidant molecules on a pristine and a mono-vacant graphene sheet. Distinct differences were observed in almost every aspect including initial kinetics, rate changes, complete/incomplete combustion, gasified regions, and the role of vacancy defects. In the case of O 2 , the nucleation stage is harder while the later stages contained no limiting behavior; The gasification kinetics is highest for H 2 O during initial periods, but the oxidative behavior changes as higher gas consumption levels are reached; CO 2 has the highest thermodynamic stability and the formation of stable intermediate structures troubles the gasification. Significant out-of-plane activity is observed in the case of H 2 O oxidant. Results suggest that there may be little overlap in the oxidation sites for CO 2 and H 2 O. In-depth atomic level investigations consistent with the experimental phenomenon will have implications for future design, process optimization, and their commercial application. [ABSTRACT FROM AUTHOR]

[Display omitted] • The wettability of molten iron on the graphite prism plane is better than that of the graphite basal plane. • The wetting process of molten iron on the graphite basal plane is different from that on the graphite prism plane. • The iron atoms in contact with the incomplete carbon structure will exhibit a cluster structure. • The exfoliation of carbon atoms in the basal model is more complicated than that in the prism model. Understanding the mechanism of the iron-carbon reactive wetting process is very important to understand the interaction between molten iron and carbonaceous materials in the ironmaking process. In this paper, the method of ReaxFF molecular dynamics simulation was used to study the microscopic mechanisms involved in the iron-carbon reactive wetting process. The study examines spreading area, contact angle, microscopic atomic structure, and the interfacial processes. It was found that the wetting process between molten iron and graphite is different for the different crystal orientations of graphite. The wettability of molten iron on the graphite prism plane is better than that on the basal plane. However, the degree of corrosion of molten iron on the graphite basal plane is greater, which is directly related to the way of exfoliation of atoms at different crystal orientation planes. The exfoliation of carbon atoms in the graphite basal model is more complicated, and there are two steps. The iron atoms are in contact with the graphite layer, leading to the formation of defects, which in turn destroy the graphite structure. Then, the iron atoms come into contact with the unsaturated carbon in the pores of the graphite, thereby exfoliating the carbon atoms from the graphitic structure. And the carbon atom exfoliation method in the graphite prism model is relatively simple. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microstructure evolution mechanism of graphene oxide deflagration phenomenon. • Functional group desorption process of GO pyrolysis at high temperature. • Hybridization statistics and graphitization degree analysis of C atoms in GO. • C-O bond length statistics and structural analysis in graphene oxide. • The release process and quantity statistics of gas molecular of GO pyrolysis. An in-depth understanding of the structural evolution of graphene oxide (GO) at high temperatures is of crucial importance for tuning the properties of GO and synthesizing graphene-related materials from GO, which still has many unknown structural changes at the atomic scale. In this work, the overall structural change process and the local structural evolution mechanism during the high-temperature pyrolysis of GO were investigated by the ReaxFF molecular dynamics simulation method. The detonation process of GO was explored for the first time at the atomic simulation level, and the detonation point of GO was found to be positively correlated with the C/O ratio, which is highly consistent with previous experimental results. The bonding pattern between C-O in GO was sorted out, and the desorption mechanism of functional groups during pyrolysis was explained in detail by analyzing the ratio of sp2 and sp3 hybridized C atoms. In addition, the effects of temperature, C/O ratio and functional group type on the small molecule pyrolysis products were also investigated. The present study provides strategies to tune GO structure by pyrolysis at high temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • This paper revealed the wetting behavior of molten iron on graphene surface from the atomic scale. • The smoother the graphene, the better the wettability of molten iron on its surface. • The wrinkle amplitude is significantly stronger than the wrinkle frequency for the wetting process. • The better the wettability of molten iron on the graphene surface, the more micro-cluster structures near the interface. Graphene has become a research hotspot in the field of materials due to its excellent properties and unique two-dimensional structure. Metal-graphene nanocomposites are usually formed by dispersing metal nanoparticles on graphene surface. Therefore, the wettability of metal on graphene is an important factor affecting the synthesis. In this paper, molecular dynamics simulation methods are used to study the wetting behavior of molten iron on the graphene surface. The changing law of the wettability of molten iron under different wrinkles of graphene was discussed in depth. The similarities and differences of wetting behavior changes are compared from the perspectives of interaction energy, spreading area, contact angle, interface atomic force and cluster analysis. The results show that the change of graphene wrinkle amplitude and wrinkle frequency have different effects on the variation of wettability. The influence of wrinkle amplitude is obviously stronger than that of wrinkle frequency. And the smoother the graphene, the better the wettability of the molten iron. Therefore, if we want to make iron-graphene composite materials, it is necessary to strictly control the flatness of graphene. [ABSTRACT FROM AUTHOR]

[Display omitted] • The influence factors of graphene oxide layer spacing on the atomic scale. • Low–temperature pyrolysis behavior of graphene oxide. • The aggregation and distribution of oxygen-containing functional. • Graphene oxide layer spacing control and membrane separation. • Application of molecular dynamics simulation in carbon materials. Due to the oxygen–containing functional groups covering the graphene oxide surface, multilayer graphene oxide has different properties. The understanding of its atomic structure and layer stacking behavior at low temperature is far from complete. This work systematically revealed how the oxygen-containing groups density, type and temperature affect the spacing of multilayer GO layers through the ReaxFF molecular dynamics simulation method. We found that the density of oxygen-containing groups is the main variable that controls the distribution of surface oxidation areas and the degree of distortion of the graphene sheets. With the increase of C/O ratio, the distribution of oxygen-containing functional groups tends to aggregate, and the deformation of graphite flakes becomes more serious. The layer spacing of multilayer GO is affected by temperature. The types of released small molecules, the degree of pyrolysis of the graphene skeleton and the interlayer spacing are all affected by OH/O ratio. With more hydroxyl groups, it is easier to release long O - H chains, and the graphene skeleton is less likely to be pyrolyzed. This in–depth investigation has helped develop a fundamental understanding of the atomic structure of graphene oxide and has laid basic foundations for an effective control of graphene layer distance and properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • The EAM potential is suitable for characterizing the microstructure of liquid Fe-C alloy, while MEAM is not. • EAM potential could accurately predict the melting point of liquid Fe-C alloy. • Increased carbon content helps to increase the complexity of the liquid Fe-C alloy microstructure. • The transformation of Fe4C units to cementite promotes viscosity increase. The liquid Fe-C alloy is the most important system in the metallurgical process and the molecular dynamics simulation were carried out to investigate the structure and properties of liquid Fe-C alloy using EAM and MEAM potential. The local structural order, transport properties and fluidity were analyzed. By comparison, the EAM potential is better than MEAM potential to simulate the properties of liquid Fe-C system. In the liquid state, the Fe-C alloy have a short-ranged ordered structure, accompanied by the transformation of Fe 4 C units to Fe 6 C units with the carbon content increasing. And the increase in carbon content could increase the complexity of the liquid structure. In terms of transport properties and fluidity, there is an inflection point when carbon content increases to 2 wt%. When the carbon content is less than 2%, the change of Fe atom transport performance is the main factor that leads to the increase of viscosity. On the contrary, when the carbon content is more than 2%, the transportation of C atom dominates. [ABSTRACT FROM AUTHOR]

• The influence of MnO content more than or less than 4 wt% on the structure and properties of slag is different. • High bacisity and the MnO content exceeds 4 wt% enhanced depolymerization of aluminosilicate structure by MnO. • The micro complexity of slag system is positively correlated with the macro viscosity. • Low basicity and high MnO promote lower liquidus temperature of slag. In this paper, molecular dynamics (MD) is used to simulate the local structural order, oxygen bond network and transportation characteristics of the slag system under different basicity, and the influence of MnO on the properties such as viscosity, liquidus temperature and enthalpy was studied. MnO or basicity will not affect the bond length and the coordination number of Si-O, but the coordination number of Al-O is slightly reduced. The conversion rate of BO and TOs to NBO or FO is accelerated when CaO/SiO 2 ratio is 1.2 and MnO exceeds 4 wt%. It indicates that an increase in MnO content at high basicity will make the depolymerization of the slag structure more obvious. The total self-diffusion coefficient of each atoms increases with the increase of basicity and MnO, while the viscosity of slag showed an opposite trend. The enthalpy of the slag increases linearly and the conditions of low basicity and high MnO are beneficial for keeping a low liquidus temperature and realizing the stable and smooth of the blast furnace. [ABSTRACT FROM AUTHOR]

Understanding the interaction of iron and carbon is of vital importance to guide the fundamental research in the fields of metallurgy and materials science. Reaxff molecular dynamics simulation method was used to study the carburizing reaction process between graphite and molten iron. It was found that the rise of temperature can promote the carburization reaction, and the graphite prism model needs to break through a potential energy barrier when the temperature rises to 2000 K, and then carbon atoms can diffuse into the molten iron more easily. Above 2000 K, the carbon saturation of the molten iron of the graphite prism model is significantly higher than that of the graphite basal model, which proves that different carbon materials and contact ways will have different effects on the carburizing results. And it also found that high temperature can promote the mass transfer. In addition, it is found that the carburizing reaction in the graphite basal model mainly occurred in the defect parts of the graphite sheet layer. There are no defects in the graphite prism model, but the carbon atoms can be stripped from the graphite structure in the form of single atoms, diatomic carbon chains and triatomic carbon chains. [Display omitted] • The carburizing process of graphite into liquid iron was investigated from atomic scale. • The graphite different surfaces have obviously different properties. • High temperature were helpful to promote the dissolution process through making the graphite structure unstable. • Carbon atoms dissolved into the liquid iron in the form of single atoms, diatomic chains and triatomic chains. [ABSTRACT FROM AUTHOR]

Using molecular dynamics simulations, the effects of different levels of calcium oxide and ferrous oxide on the local structural order, bonding network, transport characteristics, and other microstructures and viscosity of the aluminosilicate slag system were analyzed. It was found that CaO and FeO have almost no effect on the short-term ordering of aluminosilicates in the studied composition range. However, as the metal oxide content increases, the degree of depolymerization of CaO on the aluminosilicate network structure is greater than that of FeO. It shows that the degree of polymerization of calcium aluminosilicate system is lower than that of iron aluminosilicate, and the corresponding viscosity of this system decreases with the increase of metal oxide contents. When the mass fractions of CaO and FeO increase, the diffusion ability of each atom in the SiO 2 -Al 2 O 3 -CaO system is larger than that in the SiO 2 -Al 2 O 3 -FeO system. This indicates that the polymerization structure of SiO 2 -Al 2 O 3 -CaO slag system tends to be more simplified compared with SiO 2 -Al 2 O 3 -FeO system. • The similarities and differences between FeO-containg and CaO-containg slag. • Fe2+ and Ca2+ reduce the degree of polymerization as network modifiers. • 10 wt% is the turning point in which FeO or CaO plays a leading role. • Ca2+ is easier to destroy the slag structure than Fe2+ when FeO (or CaO) > 10 wt%. • A good relationship between viscosity and polymerization degree was found. [ABSTRACT FROM AUTHOR]

Background: Autism is a lifelong disability associated with several comorbidities that confound diagnosis and treatment. A better understanding of these comorbidities would facilitate diagnosis and improve treatments. Our aim was to improve the detection of comorbid diseases associated with autism.Methods: We used an FP-growth algorithm to retrospectively infer disease associations using 1488 patients with autism treated at the Guangzhou Women and Children's Medical Center. The disease network was established using Cytoscape 3.7. The rules were internally validated by 10-fold cross-validation. All rules were further verified using the Columbia Open Health Data (COHD) and by literature search.Results: We found 148 comorbid diseases including intellectual disability, developmental speech disorder, and epilepsy. The network comprised of 76 nodes and 178 directed links. 158 links were confirmed by literature search and 105 links were validated by COHD. Furthermore, we identified 14 links not previously reported.Conclusion: We demonstrate that the FP-growth algorithm can detect comorbid disease patterns, including novel ones, in patients with autism. [ABSTRACT FROM AUTHOR]