From the early Taoist diagrams of the human body to the end of the Qing dynasty and the beginning of the Republic of China,Taoists exaggerated and deformed the human spine in a shape-shifting manner.It is likely that ...From the early Taoist diagrams of the human body to the end of the Qing dynasty and the beginning of the Republic of China,Taoists exaggerated and deformed the human spine in a shape-shifting manner.It is likely that medical practitioners were influenced by this style of representation,and there are also numerous diagrams of the human body with the curved spine in the lateral-view diagrams of viscera and Ming Tang Tu(明堂图Acupuncture and Moxibustion Chart),which constantly show the human torso in an elliptical“egg shape”.No later than the Ming dynasty,medical practitioners began to depict the actual physiological spinal curve of the human body.By the Qing dynasty,the depiction of the spinal curve in medical diagrams of the human figure showed a tendency to part ways with the Taoist freehand style of the previous generation.Although the representation of the curve of the spine was very crude,later medical images of the human body at least gradually straightened the spine and no longer depicted it in a shape-shifting manner.However,the curved spine in Taoist diagrams of the human body continued to exist,and the presentation of the curved spine never changed.This way of depicting its appearance,which is very different from reality,is shaped by Taoism's special way of perceiving and viewing the body,and may also contain another form of truth.展开更多
We investigate a periodically driven Haldane model subjected to a two-stage driving scheme in the form of a step function.By using the Floquet theory,we obtain the topological phase diagram of the system.We also find ...We investigate a periodically driven Haldane model subjected to a two-stage driving scheme in the form of a step function.By using the Floquet theory,we obtain the topological phase diagram of the system.We also find that anomalous Floquet topological phases exist in the system.Focusing on examining the quench dynamics among topological phases,we analyze the site distribution of the 0-mode and p-mode edge states in long-period evolution after a quench.The results demonstrate that,under certain conditions,the site distribution of the 0-mode can be confined at the edge even in long-period evolution.Additionally,both the 0-mode and p-mode can recover and become confined at the edge in long-period evolution when the post-quench parameters(T,M_(2) /M_(1))in the phase diagram cross away from the phase boundary (M_(2)/ M_(1))=(6√3t2)/ M_(1)−1.Furthermore,we conclude that whether the edge state is confined at the edge in the long-period evolution after a quench depends on the similarity of the edge states before and after the quench.Our findings reveal some new characteristics of quench dynamics in a periodically driven system.展开更多
Ferroelectric phase transition has been identified as a promising avenue for designing high-performanceelectrocaloric materials for zero-emission and solid-state refrigeration. However, extensive research has been lim...Ferroelectric phase transition has been identified as a promising avenue for designing high-performanceelectrocaloric materials for zero-emission and solid-state refrigeration. However, extensive research has been limited todeveloping ferroelectric materials with large electrocaloric effects near room temperature, preventing them from meetingdiverse refrigeration requirements. In this study, by leveraging the room-temperature phase diagram of the (PbLa)(ZrTi)O_(3)solution, we prepared a series of Pb_(0.775)La_(0.15)Zr_(x)Ti_(1−x)O_(3) bulk ceramics spanning the ferroelectric and relaxor ferroelectricphase regions. This enabled the attainment of various phase transition features and temperatures. Finally, largeelectrocaloric effects, coupled with adjustable operation temperatures ranging from 150 to −45℃, are successfullyachieved through manipulation of the Zr/Ti ratio. This comprehensive range of operation temperatures effectively addressesdiverse refrigeration application requirements, ranging from industrial equipment to freezer cabinets. This work not onlyunderscores the expansion of the electrocaloric refrigeration application domain but also proposes a material designstrategy tailored to meet these evolving demands.展开更多
Cubic boron nitride and hexagonal boron nitride are the two predominant crystalline structures of boron nitride.They can interconvert under varying pressure and temperature conditions.However,this transformation requi...Cubic boron nitride and hexagonal boron nitride are the two predominant crystalline structures of boron nitride.They can interconvert under varying pressure and temperature conditions.However,this transformation requires overcoming significant potential barriers in dynamics,which poses great difficulty in determining the c-BN/h-BN phase boundary.This study used high-pressure in situ differential thermal measurements to ascertain the temperature of h-BN/c-BN conversion within the commonly used pressure range(3-6 GPa)for the industrial synthesis of c-BN to constrain the P-T phase boundary of h-BN/c-BN in the pressure-temperature range as much as possible.Based on the analysis of the experimental data,it is determined that the relationship between pressure and temperature conforms to the following equation:P=a+1/bT.Here,P denotes the pressure(GPa)and T is the temperature(K).The coefficients are a=-3.8±0.8 GPa and b=229.8±17.1 GPa/K.These findings call into question existing high-pressure and high-temperature phase diagrams of boron nitride,which seem to overstate the phase boundary temperature between c-BN and h-BN.The BN phase diagram obtained from this study can provide critical temperature and pressure condition guidance for the industrial synthesis of c-BN,thus optimizing synthesis efficiency and product performance.展开更多
The article raises the question of what to do with one of the main achievements of metal science in recent years—binary phase diagrams. These diagrams play a key role in the science of alloys and therefore their reli...The article raises the question of what to do with one of the main achievements of metal science in recent years—binary phase diagrams. These diagrams play a key role in the science of alloys and therefore their reliability must be complete. However, the discovery of the “ordering-separation” phase transition, which showed that in binary alloys at certain temperatures the sign of the chemical interatomic interaction changes (and, consequently, the microstructure changes), forces us to reconsider our ideas about those areas. Currently, these areas are designated on diagrams as areas of a “disordered solid solution.” This article proposes, using transmission electron microscopy, to study all the so-called solid solution regions, and apply the results obtained to the studied regions of the phase diagram.展开更多
To analyze the thermodynamic characteristics of leaching process of converter slag, φ-pH diagram of V-Ti-H2O system at oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures rangi...To analyze the thermodynamic characteristics of leaching process of converter slag, φ-pH diagram of V-Ti-H2O system at oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures ranging from 60 to 200 ℃ was obtained by recently published critically assessed standard Gibbs energies and activity coefficients of various species. When pH2, stable regions of V3＋, VO2＋ and VO2＋ exist in the stable region of TiO2. The pH values of stable regions of vanadium and titanium decrease and redox potentials become more positive with the temperature increasing. Vanadium and titanium could be separated by one-step leaching based on thermodynamics. The experiment results of pressure acid leaching of converter slag show that leaching rates of vanadium and titanium are 96.87% and 8.76% respectively, at 140 ℃ of temperature, 0.5 MPa of oxygen partial pressure, 0.055-0.075mm of particle size, 15：1 of liquid to solid ratio, 120 min of leaching time, 500 r/min of stirring speed and 200 g/L of initial acid concentration. Vanadium and titanium could be selectively separated in the pressure acid leaching process, and the experiment result is in agreement with thermodynamic calculation result.展开更多
In order to illustrate the thermodynamic characteristics of arsenic during alkaline pressure oxidation leaching process oflead anode slime(NaNO3as oxidant;NaOH as alkaline reagent),theφ-pH diagrams of As-Na-H2O,N-H2O...In order to illustrate the thermodynamic characteristics of arsenic during alkaline pressure oxidation leaching process oflead anode slime(NaNO3as oxidant;NaOH as alkaline reagent),theφ-pH diagrams of As-Na-H2O,N-H2O,As-N-Na-H2Osystems at ionic mass concentration of0.1mol/kg and temperatures of298,373,423and473K were established according tothermodynamic calculation.The results show that the existence forms of arsenic are associated with pH value,which mainly exists inthe forms of H3AsO4,24H AsO-,24HAsO-,H2AsO2-and As2O3in lower pH region,while it mainly exists in the form of3AsO4-when pH>11.14.High alkali concentration and high temperature are advantageous to the arsenic leaching.The alkaline pressureoxidation leaching experiments display that the tendency of arsenic leaching rate confirms the thermodynamic analysis resultsobtained from theφ-pH diagrams of As-N-Na-H2O system,and the highest leaching rate of arsenic reaches95.85%at453K.展开更多
Solution-phase hydrogen reduction(Sp HR)was introduced into V_(2)O_(3)preparation to overcome disadvantages of traditional reduction roasting,which include a long process,high energy consumption,and generation of poll...Solution-phase hydrogen reduction(Sp HR)was introduced into V_(2)O_(3)preparation to overcome disadvantages of traditional reduction roasting,which include a long process,high energy consumption,and generation of pollution.The research mainly focuses onφ-pH diagrams and kinetics of SpHR.Thermodynamic analysis ofφ-pH diagrams for the V-H_(2)O system demonstrates that V_(2)O_(3)preparation via Sp HR requires a high temperature,a high vanadium concentration,and sufficient hydrogen in acidic solution.Kinetic analyses show that the activation energy of V_(2)O_(3)preparation via SpHR is 38.0679 k J/mol,indicating that the reduction is controlled by a combination of interfacial chemical reaction and internal diffusion.Effects of H;partial pressure(slope K=0.05246)on the reaction rate is not as significant as the vanadium concentration(K=1.58872).V_(2)O_(3)crystals with a purity of 99.59%and a vanadium precipitation rate of 99.83%were obtained under the following conditions:pH=5-6,c(V_(2)O_(3))=0.5 mol/L,p(H;)=4 MPa,m(PdCl;)=10 mg,T=250℃,and t=2.5 h.展开更多
The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and differ...The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and different temperatures were drawn through thermodynamical calculation.With the temperature increasing,the stable regions of S and Zn(Ⅱ) in the E-pH diagrams become gradually larger,but the amplification decreases over 150℃.The impacts of leaching parameters,such as temperature,liquid to solid ratio,initial acidic concentration,leaching time,oxygen partial pressure and stirring speed on the leaching rate of Zn(Ⅱ) and conversion rate of S in the single factor of high pressure leaching experiment of ZnS in autoclave,were studied.The leaching residue was examined by X-ray fluorescence(XRF) chemical composition identification and X-ray diffraction(XRD) phase identification,and the content of the leaching solution was tested by inductively coupled plasma-atomic emission spectrometry(ICP).The experimental results indicate that the leaching rate of zinc increases from 60.05% to 97.85% and the conversion rate of sulfur increases from 38.90% to 80.92% with the temperature increasing from 110℃ to 150℃,5:1 of liquid-to-solid ratio,150 g/L of initial acidic concentration,120 min of leaching time,0.8 MPa of oxygen partial pressure,and 480 r/min of stirring speed,which tend to be stable over 150℃.The experimental results correspond with theoretical calculation.展开更多
Aqueous E pH Diagram is an essential tool for analyzing hydrometallurgical and corrosion processes. Due to the requirements for environmental protection and energy saving in recent years, waste water processing a...Aqueous E pH Diagram is an essential tool for analyzing hydrometallurgical and corrosion processes. Due to the requirements for environmental protection and energy saving in recent years, waste water processing and hydrometallurgical process of concentrate have been greatly developed. The construction of E pH diagrams has turned to multi component systems. However, there are some limits in plotting such diagrams. There is only one diagram for one multi component system, which can not reflect the truth of the aqueous reaction. In the paper, a new computation method is proposed to construct E pH diagrams. Component activity term is used to determine the boundary of stable areas. For the multi component systems, different atom ratios of elements have been taken into account. M S H 2O system is chosen to study since it is of importance in metallurgical solution. Compared with conventional methods, the algorithm is simple and conforms to real conditions.展开更多
The Dashuigou tellurium deposit is the world’s only known independent tellurium deposit.By restoring metamorphic rocks’protolith,we seek to understand not only the development and evolution trajectory of the region ...The Dashuigou tellurium deposit is the world’s only known independent tellurium deposit.By restoring metamorphic rocks’protolith,we seek to understand not only the development and evolution trajectory of the region but also the origin of the relevant deposits.While there are many ways to restore metamorphic rocks’protolith,we take the host metamorphic rocks of Dashuigou tellurium deposit and leverage various petrochemical eigenvalues and related diagrams previously proposed to reveal the deposit’s host metamorphic rocks’protolith.The petrochemical eigenvalues include molecular number,Niggli’s value,REE parity ratio,CaO/Al_(2)O_(3)ratio,Fe^(3+) /(Fe^(3+) -+Fe^(2+) )ratio,chondrite-normalized REE value,logarithmic REE value,various REE eigenvalues including scandium,Eu/Sm ratio,total REE amount,light and heavy REEs,δEu,Eu anomaly,Sm/Nd ratio,and silicon isotope δ^(30) SiNBS-29‰,etc.The petrochemical plots include ACMs,100 mg-c-(al+alk),SiO_(2)-(Na_(2)O+K_(2)O),(al+fm)-(c+alk)versus Si,FeO+Fe_(2)O^(3+) TiO)-Al_(2)O_(3)-MgO,c-mg,Al_(2)O_(3)-(Na_(2)O+K_(2)O),chondrite-normalized REE model,La/Yb-REE,and Sm/Nd ratio,etc.On the basis of these comprehensive analyses,the following conclusions are drawn,starting from the many mantle-derived types of basalt developed in the study area of different geological ages,combined with the previously published research results on the deposit s fluid inclusions and sulfur and lead isotopes.The deposit is formed by mantle degassing in the form of a mantle plume in the late Yanshanian orogeny.The degassed fluids are rich in nano-sc ale substances including Fe,Te,S,As,Bi,Au,Se,H_(2),CO_(2),N_(2),H_(2)O,and CH_(4),which are enriched by nano-effect,and then rise to a certain part of the crust in the form of mantle plume along the lithospheric fault to form the deposit.The ultimate power for tellurium mineralization was from H_(2)flow with high energy,which was produced through radiation from the melted iron of the Earth’s outer core.The H,flow results in the Earth’s degassing,as well as the mantle and crust’s uplift.展开更多
Railway Point System(RPS)is an important infrastructure in railway industry and its faults may have significant impacts on the safety and efficiency of train operations.For the fault diagnosis of RPS,most existing met...Railway Point System(RPS)is an important infrastructure in railway industry and its faults may have significant impacts on the safety and efficiency of train operations.For the fault diagnosis of RPS,most existing methods assume that sufficient samples of each failure mode are available,which may be unrealistic,especially for those modes of low occurrence frequency but with high risk.To address this issue,this work proposes a novel fault diagnosis method that only requires the power signals generated under normal RPS operations in the training stage.Specifically,the failure modes of RPS are distinguished through constructing a reasoning diagram,whose nodes are either binary logic problems or those that can be decomposed into the problems of the binary logic.Then,an unsupervised method for the signal segmentation and a fault detection method are combined to make decisions for each binary logic problem.Based on the results of decisions,the diagnostic rules are established to identify the failure modes.Finally,the data collected from multiple real-world RPSs are used for validation and the results demonstrate that the proposed method outperforms the benchmark in identifying the faults of RPSs.展开更多
A series of ethylene oxide (EO)-propylene oxide (PO) randomco-polymers (EOPO) were used to form aqueous two-phase systems (ATPS)with ammonium sulfate. Effects of EOPO's properties on the phaseseparation behaviors ...A series of ethylene oxide (EO)-propylene oxide (PO) randomco-polymers (EOPO) were used to form aqueous two-phase systems (ATPS)with ammonium sulfate. Effects of EOPO's properties on the phaseseparation behaviors and on the partition of cephalexin and7-aminodesacetoxicephalosporanic acid (7-ADCA) in ATPS wereinvestigated. Both the molar mass and molar ratio of EO to PO of EOPOcould greatly influence partition behaviors of cephalexin and 7-ADCAas well as the binodal curve of ATPS.展开更多
A new viewpoint of computer program poubaix diagram was proposed on traditional φ pH diagrams. All equilibrium principle and activity term method were used to plot φ pH diagrams for M H 2O systems based on the therm...A new viewpoint of computer program poubaix diagram was proposed on traditional φ pH diagrams. All equilibrium principle and activity term method were used to plot φ pH diagrams for M H 2O systems based on the thermochemical database developed. And a new method——arithmetic geometric method is used to solve nonlinear equations group. The calculation procedure is proved to be efficient and convergent. The method seldom depends on artificial intervention and can extend to multi component all equilibrium φ pH diagrams such as M ligand H 2O system. [展开更多
基金financed from the grant of the Fundamental Research Funds for the Central Public Welfare Research Institutes(ZZ-2023001)。
文摘From the early Taoist diagrams of the human body to the end of the Qing dynasty and the beginning of the Republic of China,Taoists exaggerated and deformed the human spine in a shape-shifting manner.It is likely that medical practitioners were influenced by this style of representation,and there are also numerous diagrams of the human body with the curved spine in the lateral-view diagrams of viscera and Ming Tang Tu(明堂图Acupuncture and Moxibustion Chart),which constantly show the human torso in an elliptical“egg shape”.No later than the Ming dynasty,medical practitioners began to depict the actual physiological spinal curve of the human body.By the Qing dynasty,the depiction of the spinal curve in medical diagrams of the human figure showed a tendency to part ways with the Taoist freehand style of the previous generation.Although the representation of the curve of the spine was very crude,later medical images of the human body at least gradually straightened the spine and no longer depicted it in a shape-shifting manner.However,the curved spine in Taoist diagrams of the human body continued to exist,and the presentation of the curved spine never changed.This way of depicting its appearance,which is very different from reality,is shaped by Taoism's special way of perceiving and viewing the body,and may also contain another form of truth.
基金the National Natural Science Foundation of China(Grant No.12004049).
文摘We investigate a periodically driven Haldane model subjected to a two-stage driving scheme in the form of a step function.By using the Floquet theory,we obtain the topological phase diagram of the system.We also find that anomalous Floquet topological phases exist in the system.Focusing on examining the quench dynamics among topological phases,we analyze the site distribution of the 0-mode and p-mode edge states in long-period evolution after a quench.The results demonstrate that,under certain conditions,the site distribution of the 0-mode can be confined at the edge even in long-period evolution.Additionally,both the 0-mode and p-mode can recover and become confined at the edge in long-period evolution when the post-quench parameters(T,M_(2) /M_(1))in the phase diagram cross away from the phase boundary (M_(2)/ M_(1))=(6√3t2)/ M_(1)−1.Furthermore,we conclude that whether the edge state is confined at the edge in the long-period evolution after a quench depends on the similarity of the edge states before and after the quench.Our findings reveal some new characteristics of quench dynamics in a periodically driven system.
基金supported by the National Natural Science Foundation of China(Nos.52302134 and 52173217)the Sichuan Science and Technology Program(No.2023NSFSC0975)+1 种基金the Scientific Research Foundation of Chengdu University of Information Technology(No.KYTZ202246)the open research fund of the Sichuan Province Key Laboratory of Information Materials and Devices Application(No.2023XXCL003).
文摘Ferroelectric phase transition has been identified as a promising avenue for designing high-performanceelectrocaloric materials for zero-emission and solid-state refrigeration. However, extensive research has been limited todeveloping ferroelectric materials with large electrocaloric effects near room temperature, preventing them from meetingdiverse refrigeration requirements. In this study, by leveraging the room-temperature phase diagram of the (PbLa)(ZrTi)O_(3)solution, we prepared a series of Pb_(0.775)La_(0.15)Zr_(x)Ti_(1−x)O_(3) bulk ceramics spanning the ferroelectric and relaxor ferroelectricphase regions. This enabled the attainment of various phase transition features and temperatures. Finally, largeelectrocaloric effects, coupled with adjustable operation temperatures ranging from 150 to −45℃, are successfullyachieved through manipulation of the Zr/Ti ratio. This comprehensive range of operation temperatures effectively addressesdiverse refrigeration application requirements, ranging from industrial equipment to freezer cabinets. This work not onlyunderscores the expansion of the electrocaloric refrigeration application domain but also proposes a material designstrategy tailored to meet these evolving demands.
基金supported by the National Key R&D Program of China(Grant No.2023YFA1406200).
文摘Cubic boron nitride and hexagonal boron nitride are the two predominant crystalline structures of boron nitride.They can interconvert under varying pressure and temperature conditions.However,this transformation requires overcoming significant potential barriers in dynamics,which poses great difficulty in determining the c-BN/h-BN phase boundary.This study used high-pressure in situ differential thermal measurements to ascertain the temperature of h-BN/c-BN conversion within the commonly used pressure range(3-6 GPa)for the industrial synthesis of c-BN to constrain the P-T phase boundary of h-BN/c-BN in the pressure-temperature range as much as possible.Based on the analysis of the experimental data,it is determined that the relationship between pressure and temperature conforms to the following equation:P=a+1/bT.Here,P denotes the pressure(GPa)and T is the temperature(K).The coefficients are a=-3.8±0.8 GPa and b=229.8±17.1 GPa/K.These findings call into question existing high-pressure and high-temperature phase diagrams of boron nitride,which seem to overstate the phase boundary temperature between c-BN and h-BN.The BN phase diagram obtained from this study can provide critical temperature and pressure condition guidance for the industrial synthesis of c-BN,thus optimizing synthesis efficiency and product performance.
文摘The article raises the question of what to do with one of the main achievements of metal science in recent years—binary phase diagrams. These diagrams play a key role in the science of alloys and therefore their reliability must be complete. However, the discovery of the “ordering-separation” phase transition, which showed that in binary alloys at certain temperatures the sign of the chemical interatomic interaction changes (and, consequently, the microstructure changes), forces us to reconsider our ideas about those areas. Currently, these areas are designated on diagrams as areas of a “disordered solid solution.” This article proposes, using transmission electron microscopy, to study all the so-called solid solution regions, and apply the results obtained to the studied regions of the phase diagram.
基金Project(2007CB613504)supported by the National Key Basic Research Program of ChinaProjects(51004033,50974035,51074047)supported by the National Natural Science Foundation of ChinaProject(2008BAB34B01)supported by National Science and Technology Support Plan of China during the 11th Five-Year Plan
文摘To analyze the thermodynamic characteristics of leaching process of converter slag, φ-pH diagram of V-Ti-H2O system at oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures ranging from 60 to 200 ℃ was obtained by recently published critically assessed standard Gibbs energies and activity coefficients of various species. When pH2, stable regions of V3＋, VO2＋ and VO2＋ exist in the stable region of TiO2. The pH values of stable regions of vanadium and titanium decrease and redox potentials become more positive with the temperature increasing. Vanadium and titanium could be separated by one-step leaching based on thermodynamics. The experiment results of pressure acid leaching of converter slag show that leaching rates of vanadium and titanium are 96.87% and 8.76% respectively, at 140 ℃ of temperature, 0.5 MPa of oxygen partial pressure, 0.055-0.075mm of particle size, 15：1 of liquid to solid ratio, 120 min of leaching time, 500 r/min of stirring speed and 200 g/L of initial acid concentration. Vanadium and titanium could be selectively separated in the pressure acid leaching process, and the experiment result is in agreement with thermodynamic calculation result.
基金Project(51564031) supported by the National Natural Science Foundation of ChinaProject(0201352042) supported by the Cooperation between School and Enterprise of China
文摘In order to illustrate the thermodynamic characteristics of arsenic during alkaline pressure oxidation leaching process oflead anode slime(NaNO3as oxidant;NaOH as alkaline reagent),theφ-pH diagrams of As-Na-H2O,N-H2O,As-N-Na-H2Osystems at ionic mass concentration of0.1mol/kg and temperatures of298,373,423and473K were established according tothermodynamic calculation.The results show that the existence forms of arsenic are associated with pH value,which mainly exists inthe forms of H3AsO4,24H AsO-,24HAsO-,H2AsO2-and As2O3in lower pH region,while it mainly exists in the form of3AsO4-when pH>11.14.High alkali concentration and high temperature are advantageous to the arsenic leaching.The alkaline pressureoxidation leaching experiments display that the tendency of arsenic leaching rate confirms the thermodynamic analysis resultsobtained from theφ-pH diagrams of As-N-Na-H2O system,and the highest leaching rate of arsenic reaches95.85%at453K.
基金financially supported by the National Key R&D Program of China(No.2020YFC1909700)Outstanding Young and Middle-aged Science and Technology Innovation Team Project of Hubei Province,China(No.T201802)the National Natural Science Foundation of China(No.52004187)。
文摘Solution-phase hydrogen reduction(Sp HR)was introduced into V_(2)O_(3)preparation to overcome disadvantages of traditional reduction roasting,which include a long process,high energy consumption,and generation of pollution.The research mainly focuses onφ-pH diagrams and kinetics of SpHR.Thermodynamic analysis ofφ-pH diagrams for the V-H_(2)O system demonstrates that V_(2)O_(3)preparation via Sp HR requires a high temperature,a high vanadium concentration,and sufficient hydrogen in acidic solution.Kinetic analyses show that the activation energy of V_(2)O_(3)preparation via SpHR is 38.0679 k J/mol,indicating that the reduction is controlled by a combination of interfacial chemical reaction and internal diffusion.Effects of H;partial pressure(slope K=0.05246)on the reaction rate is not as significant as the vanadium concentration(K=1.58872).V_(2)O_(3)crystals with a purity of 99.59%and a vanadium precipitation rate of 99.83%were obtained under the following conditions:pH=5-6,c(V_(2)O_(3))=0.5 mol/L,p(H;)=4 MPa,m(PdCl;)=10 mg,T=250℃,and t=2.5 h.
基金Project (2007CB613504) supported by the National Basic Research Program of ChinaProject(20050145029) supported by the PhD Programs Foundation of Ministry of Education of ChinaProject(2005221012) supported by the Science and Technology Talents Fund for Excellent Youth of Liaoning Province, China
文摘The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and different temperatures were drawn through thermodynamical calculation.With the temperature increasing,the stable regions of S and Zn(Ⅱ) in the E-pH diagrams become gradually larger,but the amplification decreases over 150℃.The impacts of leaching parameters,such as temperature,liquid to solid ratio,initial acidic concentration,leaching time,oxygen partial pressure and stirring speed on the leaching rate of Zn(Ⅱ) and conversion rate of S in the single factor of high pressure leaching experiment of ZnS in autoclave,were studied.The leaching residue was examined by X-ray fluorescence(XRF) chemical composition identification and X-ray diffraction(XRD) phase identification,and the content of the leaching solution was tested by inductively coupled plasma-atomic emission spectrometry(ICP).The experimental results indicate that the leaching rate of zinc increases from 60.05% to 97.85% and the conversion rate of sulfur increases from 38.90% to 80.92% with the temperature increasing from 110℃ to 150℃,5:1 of liquid-to-solid ratio,150 g/L of initial acidic concentration,120 min of leaching time,0.8 MPa of oxygen partial pressure,and 480 r/min of stirring speed,which tend to be stable over 150℃.The experimental results correspond with theoretical calculation.
文摘Aqueous E pH Diagram is an essential tool for analyzing hydrometallurgical and corrosion processes. Due to the requirements for environmental protection and energy saving in recent years, waste water processing and hydrometallurgical process of concentrate have been greatly developed. The construction of E pH diagrams has turned to multi component systems. However, there are some limits in plotting such diagrams. There is only one diagram for one multi component system, which can not reflect the truth of the aqueous reaction. In the paper, a new computation method is proposed to construct E pH diagrams. Component activity term is used to determine the boundary of stable areas. For the multi component systems, different atom ratios of elements have been taken into account. M S H 2O system is chosen to study since it is of importance in metallurgical solution. Compared with conventional methods, the algorithm is simple and conforms to real conditions.
基金supported by Orient Resources Ltd.College of Earth Sciences,Jilin University。
文摘The Dashuigou tellurium deposit is the world’s only known independent tellurium deposit.By restoring metamorphic rocks’protolith,we seek to understand not only the development and evolution trajectory of the region but also the origin of the relevant deposits.While there are many ways to restore metamorphic rocks’protolith,we take the host metamorphic rocks of Dashuigou tellurium deposit and leverage various petrochemical eigenvalues and related diagrams previously proposed to reveal the deposit’s host metamorphic rocks’protolith.The petrochemical eigenvalues include molecular number,Niggli’s value,REE parity ratio,CaO/Al_(2)O_(3)ratio,Fe^(3+) /(Fe^(3+) -+Fe^(2+) )ratio,chondrite-normalized REE value,logarithmic REE value,various REE eigenvalues including scandium,Eu/Sm ratio,total REE amount,light and heavy REEs,δEu,Eu anomaly,Sm/Nd ratio,and silicon isotope δ^(30) SiNBS-29‰,etc.The petrochemical plots include ACMs,100 mg-c-(al+alk),SiO_(2)-(Na_(2)O+K_(2)O),(al+fm)-(c+alk)versus Si,FeO+Fe_(2)O^(3+) TiO)-Al_(2)O_(3)-MgO,c-mg,Al_(2)O_(3)-(Na_(2)O+K_(2)O),chondrite-normalized REE model,La/Yb-REE,and Sm/Nd ratio,etc.On the basis of these comprehensive analyses,the following conclusions are drawn,starting from the many mantle-derived types of basalt developed in the study area of different geological ages,combined with the previously published research results on the deposit s fluid inclusions and sulfur and lead isotopes.The deposit is formed by mantle degassing in the form of a mantle plume in the late Yanshanian orogeny.The degassed fluids are rich in nano-sc ale substances including Fe,Te,S,As,Bi,Au,Se,H_(2),CO_(2),N_(2),H_(2)O,and CH_(4),which are enriched by nano-effect,and then rise to a certain part of the crust in the form of mantle plume along the lithospheric fault to form the deposit.The ultimate power for tellurium mineralization was from H_(2)flow with high energy,which was produced through radiation from the melted iron of the Earth’s outer core.The H,flow results in the Earth’s degassing,as well as the mantle and crust’s uplift.
基金supported by National Key R&D Program of China(2022YFB2602203)Talent Fund of Beijing Jiaotong University(2021RC274,I22L00131)National Natural Science Foundation of China(U1934219,52202392,52022010,U22A2046,52172322,62271486,62120106011,52172323)。
文摘Railway Point System(RPS)is an important infrastructure in railway industry and its faults may have significant impacts on the safety and efficiency of train operations.For the fault diagnosis of RPS,most existing methods assume that sufficient samples of each failure mode are available,which may be unrealistic,especially for those modes of low occurrence frequency but with high risk.To address this issue,this work proposes a novel fault diagnosis method that only requires the power signals generated under normal RPS operations in the training stage.Specifically,the failure modes of RPS are distinguished through constructing a reasoning diagram,whose nodes are either binary logic problems or those that can be decomposed into the problems of the binary logic.Then,an unsupervised method for the signal segmentation and a fault detection method are combined to make decisions for each binary logic problem.Based on the results of decisions,the diagnostic rules are established to identify the failure modes.Finally,the data collected from multiple real-world RPSs are used for validation and the results demonstrate that the proposed method outperforms the benchmark in identifying the faults of RPSs.
基金Supported by the National Natural Science Foundation of China (No. 29873014) and the Key Disciplinary Foundation of Shanghai.
文摘A series of ethylene oxide (EO)-propylene oxide (PO) randomco-polymers (EOPO) were used to form aqueous two-phase systems (ATPS)with ammonium sulfate. Effects of EOPO's properties on the phaseseparation behaviors and on the partition of cephalexin and7-aminodesacetoxicephalosporanic acid (7-ADCA) in ATPS wereinvestigated. Both the molar mass and molar ratio of EO to PO of EOPOcould greatly influence partition behaviors of cephalexin and 7-ADCAas well as the binodal curve of ATPS.
文摘A new viewpoint of computer program poubaix diagram was proposed on traditional φ pH diagrams. All equilibrium principle and activity term method were used to plot φ pH diagrams for M H 2O systems based on the thermochemical database developed. And a new method——arithmetic geometric method is used to solve nonlinear equations group. The calculation procedure is proved to be efficient and convergent. The method seldom depends on artificial intervention and can extend to multi component all equilibrium φ pH diagrams such as M ligand H 2O system. [
