There was little research on the changes and interconversion of organic compounds in the intermediate liquid-phase productsin the hydrogen production by anaerobic fermentation of coal.The types and concentrations of t...There was little research on the changes and interconversion of organic compounds in the intermediate liquid-phase productsin the hydrogen production by anaerobic fermentation of coal.The types and concentrations of the intermediate liquid-phase products are not only related to the efficiency of coal conversion into biohydrogen,but one of the important contents of study on the generation mechanism of biohydrogen from coal.In order to study the change of key liquid phase products in the process of bio-hydrogen production from coal,the simulation experiments of bio-hydrogen production were conducted under suitable environmental conditions using lignite from Daliuta,Shaanxi province.The hydrogen concentration and key liquid phase products were measured using gas chromatography and GC-MS,respectively,to reveal its change.The results show that:(1)there is correspondence between the key liquid phase products and hydrogen yield.The saturated alkanes and cyclic hydrocarbons show a trend of first increasing,then decreasing,and finally increasing,but the changes of proteinaceous materials are just the opposite,which is correspondent to the initial stage,peak stage and terminal stage of hydrogen production,respectively.(2)The short-chain volatile fatty acids are accumulated gradually in the process of hydrogen production,and the short-chain acids of aromatic show a trend of first increasing,then decreasing,increase again and finally decreasing,which is correspondent to the different biochemical reactions,such as the release of small molecules,the utilization of microorganisms,hydrocarbon oxidation and the redegradation of macromolecule.(3)The lipids,aldehydes and ketones are the parent substances of acid production,and the changes are related to the increased acids to a certain extent.This research not only reveals the biochemical effects between gas and liquid phases,but further enriches the theory of bio-hydrogen production from coal.展开更多
This study analyzed the prevalent physicochemical phases of smelting slag from the perspective of data science and chemistry.Findings delineated the silicate phase as the pivotal and predominant constraining phase for...This study analyzed the prevalent physicochemical phases of smelting slag from the perspective of data science and chemistry.Findings delineated the silicate phase as the pivotal and predominant constraining phase for the resource utilization of smelting slag.An intricate correlation between metallic elements and dominant phases was constructed.Typical silicate phase olivine(OL)was synthesized as a paradigm to examine alkali depolymerization,unveiling the optimal conditions for such depolymerization to be an alkali to olivine molar ratio of 1:5,a reaction temperature of 700℃,and a duration of 3 h.The underlying mechanism of alkali depolymerization within silicate phases was elucidated under these parameters.The reaction mechanism of alkali depolymerization within silicate phases can be encapsulated in three sequential steps:(1)NaOH dissociation and subsequent adsorption of OH^(-)to cationic(Mg or Fe)sites;(2)disruption of cation-oxygen bonds,leading to the formation of hydroxide compounds,which then underwent oxidation;(3)Na^(+)occupied the resultant cation vacancy sites,instigating further depolymerization of the intermediate Na_(2)(Mg,Fe)SiO_(4).The articulated mechanism is anticipated to furnish theoretical underpinnings for the efficacious recuperation of metals from smelting slags.展开更多
Full-period signal acquisition of vibration signal plays a vital role in the health monitoring and fault diagnosis of modern industrial equipment group. The traditional full-period signal acquisition methods usually n...Full-period signal acquisition of vibration signal plays a vital role in the health monitoring and fault diagnosis of modern industrial equipment group. The traditional full-period signal acquisition methods usually need not only a reference signal generated from special key phase device but also a reserved position, which is only suitable for a small number of particular equipment. A novel full-period signal acquisition method without key phase is proposed to construct the time-frequency method with strong energy concentration called the synchrosqueezing generalized S-Transform(SGST), combining together the Teager energy operator(TEO) and self-adaptive correlation analysis(SACA) based on the vibration signals of both gear and cylinder head. Actual vibration signals of diesel engine are employed to verify the feasibility and effectiveness of the proposed method by comparing with traditional method with special key phase device. By comparisons, the results show that full-period signal acquisition method without key phase has approximate accuracy for diesel engine under different working conditions.展开更多
We prot）ose a security-enhanced double-random phase encryption （DRPE） scheme using orthogonally encoded image and electronically synthesized key data to cope with the security problem of DRPE technique caused by fi...We prot）ose a security-enhanced double-random phase encryption （DRPE） scheme using orthogonally encoded image and electronically synthesized key data to cope with the security problem of DRPE technique caused by fixed double-random phase masks for eneryption. In the proposed scheme, we adopt the electronically synthesized key to frequently update the phase mask using a spatial light modulator, and also employ the orthogonal encoding technique to encode the image and electronically synthesized key data, which can enhance the security of both data. We provide detailed procedures for eneryption and decryption of the proposed scheme, and provide the simulation results to show the eneryption effects of the proposed scheme.展开更多
基金Project supported by the National Natural Science Foundation of China“Response Mechanism of Trace Elements to Coal Methane Generation”(No.41502158)Henan Science and Technology Key Project“Key Technologies and Applications of Coal and Straw Synergistic Conversion of Biomethane”(No.:182102310845).
文摘There was little research on the changes and interconversion of organic compounds in the intermediate liquid-phase productsin the hydrogen production by anaerobic fermentation of coal.The types and concentrations of the intermediate liquid-phase products are not only related to the efficiency of coal conversion into biohydrogen,but one of the important contents of study on the generation mechanism of biohydrogen from coal.In order to study the change of key liquid phase products in the process of bio-hydrogen production from coal,the simulation experiments of bio-hydrogen production were conducted under suitable environmental conditions using lignite from Daliuta,Shaanxi province.The hydrogen concentration and key liquid phase products were measured using gas chromatography and GC-MS,respectively,to reveal its change.The results show that:(1)there is correspondence between the key liquid phase products and hydrogen yield.The saturated alkanes and cyclic hydrocarbons show a trend of first increasing,then decreasing,and finally increasing,but the changes of proteinaceous materials are just the opposite,which is correspondent to the initial stage,peak stage and terminal stage of hydrogen production,respectively.(2)The short-chain volatile fatty acids are accumulated gradually in the process of hydrogen production,and the short-chain acids of aromatic show a trend of first increasing,then decreasing,increase again and finally decreasing,which is correspondent to the different biochemical reactions,such as the release of small molecules,the utilization of microorganisms,hydrocarbon oxidation and the redegradation of macromolecule.(3)The lipids,aldehydes and ketones are the parent substances of acid production,and the changes are related to the increased acids to a certain extent.This research not only reveals the biochemical effects between gas and liquid phases,but further enriches the theory of bio-hydrogen production from coal.
基金financially supported by the National Natural Science Foundation of China(Nos.22006040 and 22376070)the National Key Research and Development Program of China(No.2019YFA0210404)the Research Project on Characteristic Innovation of University Teachers(No.2022XJZZ02)。
文摘This study analyzed the prevalent physicochemical phases of smelting slag from the perspective of data science and chemistry.Findings delineated the silicate phase as the pivotal and predominant constraining phase for the resource utilization of smelting slag.An intricate correlation between metallic elements and dominant phases was constructed.Typical silicate phase olivine(OL)was synthesized as a paradigm to examine alkali depolymerization,unveiling the optimal conditions for such depolymerization to be an alkali to olivine molar ratio of 1:5,a reaction temperature of 700℃,and a duration of 3 h.The underlying mechanism of alkali depolymerization within silicate phases was elucidated under these parameters.The reaction mechanism of alkali depolymerization within silicate phases can be encapsulated in three sequential steps:(1)NaOH dissociation and subsequent adsorption of OH^(-)to cationic(Mg or Fe)sites;(2)disruption of cation-oxygen bonds,leading to the formation of hydroxide compounds,which then underwent oxidation;(3)Na^(+)occupied the resultant cation vacancy sites,instigating further depolymerization of the intermediate Na_(2)(Mg,Fe)SiO_(4).The articulated mechanism is anticipated to furnish theoretical underpinnings for the efficacious recuperation of metals from smelting slags.
基金Supported by the National Key Research and Development Plan of China(No.2016YFF0203305)the Fundamental Research Funds for the Central Universities of China(No.JD1912)Double First-Rate Construction Special Funds(No.ZD1601).
文摘Full-period signal acquisition of vibration signal plays a vital role in the health monitoring and fault diagnosis of modern industrial equipment group. The traditional full-period signal acquisition methods usually need not only a reference signal generated from special key phase device but also a reserved position, which is only suitable for a small number of particular equipment. A novel full-period signal acquisition method without key phase is proposed to construct the time-frequency method with strong energy concentration called the synchrosqueezing generalized S-Transform(SGST), combining together the Teager energy operator(TEO) and self-adaptive correlation analysis(SACA) based on the vibration signals of both gear and cylinder head. Actual vibration signals of diesel engine are employed to verify the feasibility and effectiveness of the proposed method by comparing with traditional method with special key phase device. By comparisons, the results show that full-period signal acquisition method without key phase has approximate accuracy for diesel engine under different working conditions.
基金supported in part by the Basic Science Research Program through the National Research Foundation of Korea Funded by the Ministry of Science,ICT & Future Planning(No.2011-0030079)the Ministry of Education(No.NRF-2013R1A1A2057549)
文摘We prot）ose a security-enhanced double-random phase encryption （DRPE） scheme using orthogonally encoded image and electronically synthesized key data to cope with the security problem of DRPE technique caused by fixed double-random phase masks for eneryption. In the proposed scheme, we adopt the electronically synthesized key to frequently update the phase mask using a spatial light modulator, and also employ the orthogonal encoding technique to encode the image and electronically synthesized key data, which can enhance the security of both data. We provide detailed procedures for eneryption and decryption of the proposed scheme, and provide the simulation results to show the eneryption effects of the proposed scheme.
