Background:Apolipoprotein E4(ApoE4)allele is the strongest genetic risk factor for late-onset Alzheimer's disease,and it can aggravate depressive symptoms in non-AD patients.However,the impact of ApoE4 on AD-assoc...Background:Apolipoprotein E4(ApoE4)allele is the strongest genetic risk factor for late-onset Alzheimer's disease,and it can aggravate depressive symptoms in non-AD patients.However,the impact of ApoE4 on AD-associated depression-l ike behaviors and its underlying pathogenic mechanisms remain unclear.Methods:This study developed a 5xFAD mouse model overexpressing human ApoE4(E4FAD).Behavioral assessments and synaptic function tests were conducted to explore the effects of ApoE4 on cognition and depression in 5xFAD mice.Changes in peripheral and central lipid metabolism,as well as the levels of serotonin(5-HT)andγ-aminobutyric acid(GABA)neurotransmitters in the prefrontal cortex,were examined.In addition,the protein levels of 24-dehydrocholesterol reductase/glycogen synthase kinase-3 beta/mammalian target of rapamycin(DHCR24/GSK3β/m TOR)and postsynaptic density protein 95/calmodulin-dependent protein kinase II/brain-derived neurotrophic factor(PSD95/CaMK-II/BDNF)were measured to investigate the molecular mechanism underlying the effects of ApoE4 on AD mice.Results:Compared with 5xFAD mice,E4FAD mice exhibited more severe depressionlike behaviors and cognitive impairments.These mice also exhibited increased amyloid-beta deposition in the hippocampus,increased astrocyte numbers,and decreased expression of depression-related neurotransmitters 5-HT and GABA in the prefrontal cortex.Furthermore,lipid metabolism disorders were observed in E4FAD,manifesting as elevated low-density lipoprotein cholesterol and reduced high-density lipoprotein cholesterol in peripheral blood,decreased cholesterol level in the prefrontal cortex,and reduced expression of key enzymes and proteins related to cholesterol synthesis and homeostasis.Abnormal expression of proteins related to the DHCR24/GSK3β/m TOR and PSD95/CaMK-II/BDNF pathways was also observed.Conclusion:This study found that ApoE4 overexpression exacerbates depressionlike behaviors in 5xFAD mice and confirmed that ApoE4 reduces cognitive function in these mice.The mechanism may involve the induction of central and peripheral lipid metabolism disorders.Therefore,modulating ApoE expression or function to restore cellular lipid homeostasis may be a promising therapeutic target for AD comorbid with depression.This study also provided a better animal model for studying AD comorbid with depression.展开更多
Background:Alzheimer's disease(AD)and lung cancer are leading causes of mortality among the older population.Epidemiological evidence suggests an antagonistic relationship between them,whereby patients with AD exh...Background:Alzheimer's disease(AD)and lung cancer are leading causes of mortality among the older population.Epidemiological evidence suggests an antagonistic relationship between them,whereby patients with AD exhibit a reduced risk of developing cancer and vice versa.However,the precise mechanism by which AD antagonizes lung cancer progression warrants further elucidation.Methods:To this end,we established a co-morbidity model using 5xFAD transgenic mice induced with the carcinogen urethane.We visualized and quantified surface lung tumor colonies,assessed pathological parameters associated with lung cancer and AD using histopathological analysis,and employed single-cell sequencing and molecular pathological analyses to explore the mechanisms by which AD confers resistance to lung cancer.Results:Our findings revealed a significant reduction in lung tumor incidence in the AD group compared with that in the wild-type(WT)group.The results indicated a close association between AD-induced inhibition of lung tumor progression and iron homeostasis imbalance and increased oxidative stress.Moreover,greater CD8^(+)T cytotoxic lymphocyte and effector natural killer cell infiltration in the lung tumor tissues of AD mice and enhanced CD8^(+)T cytotoxic lymphocyte-mediated killing of target cells may be the primary factors contributing to the inhibition of lung tumor growth in the presence of AD.Conclusion:This study identified essential mechanisms through which AD suppresses lung tumorigenesis,thereby providing targets for potential therapeutic interventions in these diseases.展开更多
The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is ...The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is a promising plastic chemical recycling technology that offers benefits such as simple processes,convenient operation,and recyclable solvents.However,selecting suitable solvents remains a challenge.This study establishes a virtual solvent database containing 530 common inorganic and organic solvents.By calculating theσ-profile of polyvinyl chloride(PVC)and polyethylene(PE)models using quantum mechanical calculations and employing the conductor-like screening model for real solvents(COSMO-RS)method,the solubility performance of these solvents for PVC and PE at different temperatures was predicted.The results demonstrate the high accuracy of the COSMO-RS method in predicting solubility.By comparing the solubility differences between PVC and PE in different solvents,a series of solvents suitable for selectively removing PVC from mixed plastics were identified,for example,N-methyl-2-pyrrolidone(NMP),dimethyl sulfoxide(DMSO),tetrahydrofuran(THF),and N,Ndimethylacetamide(DMAc).This method provides a novel solution to the solvent selection challenge in plastic chemical recycling,potentially shortening the research and development period,reducing experimental costs,and promoting the development of green and refined waste plastic recycling processes.展开更多
Hydrotreatment is a critical process in the petrochemical industry to produce gasoline or diesel.Proper kinetic models and accurate kinetic parameters of hydrotreatment reactions are important for the industrial react...Hydrotreatment is a critical process in the petrochemical industry to produce gasoline or diesel.Proper kinetic models and accurate kinetic parameters of hydrotreatment reactions are important for the industrial reactor design and scale-up research.In this work,hydrogenation kinetics of alkene and aromatic model compounds were studied thoroughly to provide deep understanding on alkene and aromatic hydrogenation behaviors in gasoline and diesel hydrotreating.Commercial NiMo hydrotreatment catalysts were used to obtain experimental data of hydrogenation reactions.Cyclohexene,1-octene,naphthalene and phenanthrene were used as model compounds of alkenes and aromatics.Langmuir-Hinshelwood-Hougen-Watson(LHHW)kinetic models for hydrotreatment reactions were established.In addition,phase equilibrium calculations were combined with kinetic study,and it is discovered that using calculated liquid phase compositions as kinetic model input could greatly enhance the accuracy of kinetic models and the quality of kinetic parameters,leading to higher accordance with experimental results.Using kinetic models and phase equilibrium analysis,the effect of reaction conditions(temperature,pressure,and H_(2)/oil ratio)on reaction rates were also predicted and clarified.The importance of phase equilibrium in kinetic analysis for hydrotreating reactions was demonstrated in this study,which provides an effective approach for future hydrotreatment reactor design and catalyst optimization.展开更多
SiO2-supported Ni-Mo bimetallic phosphides were prepared by temperature-programmed reduction （TPR） method from the phosphate precur- sors calcined at different temperatures. Their properties were characterized by me...SiO2-supported Ni-Mo bimetallic phosphides were prepared by temperature-programmed reduction （TPR） method from the phosphate precur- sors calcined at different temperatures. Their properties were characterized by means of ultraviolet-visible diffuse reflectance spectroscopy （UV-Vis DRS）, H2 temperature-programmed reduction （H2-TPR）, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, CO chemisorption, H2 and NH3 temperature-programmed desorptions （H2-TPD and NH3-TPD）. Their catalytic performances for the deoxygena- tion of methyl laurate were tested in a fixed-bed reactor. When the precursors were calcined at 400 and 500 ℃, respectively, NiMoP2 phase could be formed apart from Ni2P and MoP phases in the prepared C400 and C500 catalysts. However, when the precursors were calcined at 600, 700 and 800 ℃, respectively, only Ni2P and MoP phases could be detected in the prepared C600, C700 and C800 catalysts. Also, in C400, C500 and C600 catalysts, Mo atoms were found to be entered in the lattice of Ni2P phase, but the entering extent became less with the increase of calcination temperature. As the calcination temperature of the precursor increased, the interaction between Ni and Mo in the prepared catalysts decreased, and the phosphide crystallite size tended to increase, subsequently leading to the decrease in the surface metal site density and the acid amount. C600 catalyst showed the highest activity among the tested ones for the deoxygenation of methyl laurate. As the calcination temperature of the precursor increased, the selectivity to C12 hydrocarbons decreased while the selectivity to C11 hydrocarbons tended to increase. This can be mainly attributed to the decreased Ni-Mo interaction and the increased phosphide particle size. In sum, the structure and performance of Ni-Mo bimetallic phosphide catalyst can be tuned by the calcination temperature of precursor.展开更多
Petroleum has played a vital role as the major supplier of materials and energy during the evolution of human civilization.Given the change in demand for energy from high to low carbon and ultimately net zero carbon,t...Petroleum has played a vital role as the major supplier of materials and energy during the evolution of human civilization.Given the change in demand for energy from high to low carbon and ultimately net zero carbon,the energy framework has undergone revolutionary changes.The energy attribute of petroleum will be gradually weakened,while the material and CO_(2)emission attributes will be gradually strengthened.Thus,the petrochemical processing basis,scientific concepts,and ideas will undergo major adjustments to reshape the petrochemical industry.Hence,it is necessary to reconsider the evolution of the petrochemical industry from a historical perspective and to clarify the historical causes,development contexts,and possible challenges in future development.Herein,we critically reassess the key drivers and rules guiding the development of the petrochemical industry and propose a reconstruction strategy based on simplified engineering thinking,innate nature of energy and material,and CO_(2)emissions,which can be realized through the integration of gasification with CO as the target product and recent C1 chemistry targeting the precise synthesis of chemicals.The concept of the petrochemical industry will change from the product-based process of selection and transformation of raw material molecules to the process of carbon atom reconfiguration driven by product CO_(2)emissions.More accurate management of C atoms can be accomplished with greatly improved utilization efficiency and the reduction of separation intensity and CO_(2)emissions via the stepwise introduction of a new approach in the current petrochemical industry.展开更多
Background:Hypothyroxinemia is a subclinical thyroid hormone deficiency in which the mother has inadequate levels of T_(4) during pregnancy.The fetus relies entirely on the mother's T_(4) hormone level for early n...Background:Hypothyroxinemia is a subclinical thyroid hormone deficiency in which the mother has inadequate levels of T_(4) during pregnancy.The fetus relies entirely on the mother's T_(4) hormone level for early neurodevelopment.Isolated maternal hypothyroxinemia(IMH)in the first trimester of pregnancy can lead to lower intelligence,lower motor scores,and a higher risk of mental illness in descendants.Here,we focus on the autism-like behavior of IMH offspring.Methods:The animals were administered 1 ppm of propylthiouracil(PTU)for 9 weeks.Then,the concentrations of T_(3),T_(4),and thyroid-stimulating hormone(TSH)were detected using enzyme-linked immunosorbent assay(ELISA)to verify the developed animal model of IMH.We performed four behavioral experiments,including the marble burying test,open-field test,three-chamber sociability test,and Morris water maze,to explore the autistic-like behavior of 40-day-old offspring rats.Results:The ELISA test showed that the serum T_(3) and TSH concentrations in the model group were normal compared with the negative control group,whereas the T_(4) concentration decreased.In the behavioral experiments,the number of hidden marbles in the offspring of IMH increased significantly,the frequency of entering the central compartment decreased,and the social ratio decreased significantly.Conclusion:The animal model of IMH was developed by the administration of 1 ppm of PTU for 9 weeks,and there were autistic-like behavior changes such as anxiety,weakened social ability,and repeated stereotyping in the IMH offspring by 40 days.展开更多
The emerging endoplasmic recticulum(ER)crosstalk system demands a more reliable approach for ER-targeting fluorophores to explore ER-associated biochemical species and events.Providing the aromatic sulfonamides’affin...The emerging endoplasmic recticulum(ER)crosstalk system demands a more reliable approach for ER-targeting fluorophores to explore ER-associated biochemical species and events.Providing the aromatic sulfonamides’affinity to ATP-sensitive potassium channel protein localized mainly on ER membrane,the sulfonamide fluorophore 4-amino-7-sulfamoylbenzoxadiazole(SBD)was modified to construct ER self-targeting fluorophores without any additional targeting group by alternating the N-substituent structure and numbers of its 4-amino and 7-sulfamoyl groups.The results revealed that a ClogP value over 3.0 endowed those SBDs the ER self-targetability effectively.This provides a strategy to devise an ER-targeting probe by simply modifying the 4-amino group of SBDs as a sensing moiety to make the probe CLogP over 3.0 despite the CLogP value of parent SBDs,and two ER-targeting Zn^(2+)probes ER-SBD-Zn1 and ER-SBD-Zn2 were obtained following this idea.Moreover,ER Zn^(2+)tracking with ER-SBD-Zn1 disclosed for the first time tunicamycin concentration-dependent ER Zn^(2+)fluctuation behavior during ER stress induction.展开更多
Thioetherification between mercaptan and diolefin is an efficient process to remove mercaptans in FCC gasoline at mild condition, during which the selective hydrogenation of diolefin to monoolefin is also expected. He...Thioetherification between mercaptan and diolefin is an efficient process to remove mercaptans in FCC gasoline at mild condition, during which the selective hydrogenation of diolefin to monoolefin is also expected. Here, Si O2 supported transition metal（Fe, Co, Ni, Mo and W） phosphides were tested for the thioetherification of isoprene and butanethiol on a fixed-bed reactor at 120℃ and 1.5 MPa H2, and their structure before and after reaction was characterized by means of XRD, HRTEM, N2 sorption, CO chemisorption, NH3-TPD, XPS and TG. It was found that, among different metal phosphides, Mo P/Si O2 showed the best performance, and the optimal nominal Mo P loading was 25%. Apart from the nature of metal, the density of metal and acid sites determined the catalyst performance. Metal site was mainly responsible for hydrogenation of isoprene, while acid site dominantly contributed to the thioetherification and the polymerization of olefins. Moreover, a balance between metallic and acidic functions is required to arrive at a desired performance. Excessive metal sites or acid sites led to the over-hydrogenation of isoprene or the severe polymerization of olefins, respectively. 25%Mo P/Si O2 was tested for 37 h time on stream, and butanethiol conversion maintained at 100%; although isoprene conversion remarkably decreased, the selectivity to isopentenes exceeded 80% after reaction for 11 h. We suggest that the deactivation of Mo P/Si O2 is mainly ascribed to the butanethiol poisoning and the carbonaceous deposit, especially the former.展开更多
Catalytic steam reforming is a promising route for tar conversion to high energy syngas in the process of biomass gasification. However, the catalyst deactivation caused by the deposition of residual carbon is still a...Catalytic steam reforming is a promising route for tar conversion to high energy syngas in the process of biomass gasification. However, the catalyst deactivation caused by the deposition of residual carbon is still a major challenge. In this paper, a modified Ni-based Ni-Co/Al2O3-CaO (Ni-Co/AC) catalyst and a conventional Ni/Al2O3 (Ni/A) catalyst were prepared and tested for tar catalytic removal in which toluene was selected as the model component. Experiments were conducted to reveal the influences of the reaction temperature and the ratio between steam to carbon on the toluene conversion and the hydrogen yield. The physicochemical properties of the modified Ni-based catalyst were determined by a series of characterization methods. The results indicated that the Ni-Co alloy was determined over the Ni-Co/AC catalyst. The doping of CaO and the presence of Ni-Co alloy promoted the performance of toluene catalytic dissociation over Ni-Co/AC catalyst compared with that over Ni/A catalyst. After testing in steam for 40 h, the carbon conversion over Ni-Co/AC maintained above 86% and its resistance to carbon deposition was superior to Ni/A catalyst.展开更多
The 5754 aluminum alloy has been widely used in the automotive industry to reduce the weight of vehicles.The weld-bonding(WB)process comprising resistance spot welding and adhesive bonding processes effectively improv...The 5754 aluminum alloy has been widely used in the automotive industry to reduce the weight of vehicles.The weld-bonding(WB)process comprising resistance spot welding and adhesive bonding processes effectively improves the mechanical properties of joints.However,it is still a great challenge in the WB process to obtain high-quality and defect-free nuggets of aluminum alloys.In this study,the parameters of the WB process are optimized and the mechanism of generation of defects during WB is analyzed.The results show that the welding parameters have a significant effect on the nugget sizes,among which the welding current plays the most important role.The residual adhesive can easily cause defects during welding,e.g.,expulsion and porosity in the nugget.This can be effectively avoided by optimizing the welding parameters.In addition,the gas in the joints is effectively reduced by adding an appropriate preheating pulse prior to welding,thus lowering the damage degree of the adhesive layer.As a result,welded joints with better weld nugget quality and more stable mechanical properties are obtained.展开更多
基金CAMS initiative for Innovative Medicine of China,Grant/Award Number:2021-I2M-1-034。
文摘Background:Apolipoprotein E4(ApoE4)allele is the strongest genetic risk factor for late-onset Alzheimer's disease,and it can aggravate depressive symptoms in non-AD patients.However,the impact of ApoE4 on AD-associated depression-l ike behaviors and its underlying pathogenic mechanisms remain unclear.Methods:This study developed a 5xFAD mouse model overexpressing human ApoE4(E4FAD).Behavioral assessments and synaptic function tests were conducted to explore the effects of ApoE4 on cognition and depression in 5xFAD mice.Changes in peripheral and central lipid metabolism,as well as the levels of serotonin(5-HT)andγ-aminobutyric acid(GABA)neurotransmitters in the prefrontal cortex,were examined.In addition,the protein levels of 24-dehydrocholesterol reductase/glycogen synthase kinase-3 beta/mammalian target of rapamycin(DHCR24/GSK3β/m TOR)and postsynaptic density protein 95/calmodulin-dependent protein kinase II/brain-derived neurotrophic factor(PSD95/CaMK-II/BDNF)were measured to investigate the molecular mechanism underlying the effects of ApoE4 on AD mice.Results:Compared with 5xFAD mice,E4FAD mice exhibited more severe depressionlike behaviors and cognitive impairments.These mice also exhibited increased amyloid-beta deposition in the hippocampus,increased astrocyte numbers,and decreased expression of depression-related neurotransmitters 5-HT and GABA in the prefrontal cortex.Furthermore,lipid metabolism disorders were observed in E4FAD,manifesting as elevated low-density lipoprotein cholesterol and reduced high-density lipoprotein cholesterol in peripheral blood,decreased cholesterol level in the prefrontal cortex,and reduced expression of key enzymes and proteins related to cholesterol synthesis and homeostasis.Abnormal expression of proteins related to the DHCR24/GSK3β/m TOR and PSD95/CaMK-II/BDNF pathways was also observed.Conclusion:This study found that ApoE4 overexpression exacerbates depressionlike behaviors in 5xFAD mice and confirmed that ApoE4 reduces cognitive function in these mice.The mechanism may involve the induction of central and peripheral lipid metabolism disorders.Therefore,modulating ApoE expression or function to restore cellular lipid homeostasis may be a promising therapeutic target for AD comorbid with depression.This study also provided a better animal model for studying AD comorbid with depression.
基金CAMS Innovation Fund for Medical Science,Grant/Award Number:2021-I2M-1-034The Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences,Grant/Award Number:2023-PT180-01。
文摘Background:Alzheimer's disease(AD)and lung cancer are leading causes of mortality among the older population.Epidemiological evidence suggests an antagonistic relationship between them,whereby patients with AD exhibit a reduced risk of developing cancer and vice versa.However,the precise mechanism by which AD antagonizes lung cancer progression warrants further elucidation.Methods:To this end,we established a co-morbidity model using 5xFAD transgenic mice induced with the carcinogen urethane.We visualized and quantified surface lung tumor colonies,assessed pathological parameters associated with lung cancer and AD using histopathological analysis,and employed single-cell sequencing and molecular pathological analyses to explore the mechanisms by which AD confers resistance to lung cancer.Results:Our findings revealed a significant reduction in lung tumor incidence in the AD group compared with that in the wild-type(WT)group.The results indicated a close association between AD-induced inhibition of lung tumor progression and iron homeostasis imbalance and increased oxidative stress.Moreover,greater CD8^(+)T cytotoxic lymphocyte and effector natural killer cell infiltration in the lung tumor tissues of AD mice and enhanced CD8^(+)T cytotoxic lymphocyte-mediated killing of target cells may be the primary factors contributing to the inhibition of lung tumor growth in the presence of AD.Conclusion:This study identified essential mechanisms through which AD suppresses lung tumorigenesis,thereby providing targets for potential therapeutic interventions in these diseases.
基金financially supported by SINOPEC Research Institute of Petroleum Processing Co.,Ltd.the National Natural Science Foundation of China(22302220)+2 种基金the Shanxi Province Science Foundation for Youth(202203021222403)Funding support was also received from the Synfuels China Co.,Ltd.the Institute of Coal Chemistry,Chinese Academy of Sciences。
文摘The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is a promising plastic chemical recycling technology that offers benefits such as simple processes,convenient operation,and recyclable solvents.However,selecting suitable solvents remains a challenge.This study establishes a virtual solvent database containing 530 common inorganic and organic solvents.By calculating theσ-profile of polyvinyl chloride(PVC)and polyethylene(PE)models using quantum mechanical calculations and employing the conductor-like screening model for real solvents(COSMO-RS)method,the solubility performance of these solvents for PVC and PE at different temperatures was predicted.The results demonstrate the high accuracy of the COSMO-RS method in predicting solubility.By comparing the solubility differences between PVC and PE in different solvents,a series of solvents suitable for selectively removing PVC from mixed plastics were identified,for example,N-methyl-2-pyrrolidone(NMP),dimethyl sulfoxide(DMSO),tetrahydrofuran(THF),and N,Ndimethylacetamide(DMAc).This method provides a novel solution to the solvent selection challenge in plastic chemical recycling,potentially shortening the research and development period,reducing experimental costs,and promoting the development of green and refined waste plastic recycling processes.
基金funding support provided by the National Key Research&Development of China(2022YFA1504401)the Project of Cultivation for Young Top-notch Talents of Beijing Municipal Institutions(BPHR202203094)Young Elite Scientists Sponsorship Program by the BAST(BYESS2023256).
文摘Hydrotreatment is a critical process in the petrochemical industry to produce gasoline or diesel.Proper kinetic models and accurate kinetic parameters of hydrotreatment reactions are important for the industrial reactor design and scale-up research.In this work,hydrogenation kinetics of alkene and aromatic model compounds were studied thoroughly to provide deep understanding on alkene and aromatic hydrogenation behaviors in gasoline and diesel hydrotreating.Commercial NiMo hydrotreatment catalysts were used to obtain experimental data of hydrogenation reactions.Cyclohexene,1-octene,naphthalene and phenanthrene were used as model compounds of alkenes and aromatics.Langmuir-Hinshelwood-Hougen-Watson(LHHW)kinetic models for hydrotreatment reactions were established.In addition,phase equilibrium calculations were combined with kinetic study,and it is discovered that using calculated liquid phase compositions as kinetic model input could greatly enhance the accuracy of kinetic models and the quality of kinetic parameters,leading to higher accordance with experimental results.Using kinetic models and phase equilibrium analysis,the effect of reaction conditions(temperature,pressure,and H_(2)/oil ratio)on reaction rates were also predicted and clarified.The importance of phase equilibrium in kinetic analysis for hydrotreating reactions was demonstrated in this study,which provides an effective approach for future hydrotreatment reactor design and catalyst optimization.
基金supported by the National Natural Science Foundation of China(No.21176177)the Natural Science Foundation of Tianjin(No.12JCYBJC13200)State Key Laboratory of Catalytic Materials and Reaction Engineering(RIPP,SINOPEC)
文摘SiO2-supported Ni-Mo bimetallic phosphides were prepared by temperature-programmed reduction （TPR） method from the phosphate precur- sors calcined at different temperatures. Their properties were characterized by means of ultraviolet-visible diffuse reflectance spectroscopy （UV-Vis DRS）, H2 temperature-programmed reduction （H2-TPR）, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, CO chemisorption, H2 and NH3 temperature-programmed desorptions （H2-TPD and NH3-TPD）. Their catalytic performances for the deoxygena- tion of methyl laurate were tested in a fixed-bed reactor. When the precursors were calcined at 400 and 500 ℃, respectively, NiMoP2 phase could be formed apart from Ni2P and MoP phases in the prepared C400 and C500 catalysts. However, when the precursors were calcined at 600, 700 and 800 ℃, respectively, only Ni2P and MoP phases could be detected in the prepared C600, C700 and C800 catalysts. Also, in C400, C500 and C600 catalysts, Mo atoms were found to be entered in the lattice of Ni2P phase, but the entering extent became less with the increase of calcination temperature. As the calcination temperature of the precursor increased, the interaction between Ni and Mo in the prepared catalysts decreased, and the phosphide crystallite size tended to increase, subsequently leading to the decrease in the surface metal site density and the acid amount. C600 catalyst showed the highest activity among the tested ones for the deoxygenation of methyl laurate. As the calcination temperature of the precursor increased, the selectivity to C12 hydrocarbons decreased while the selectivity to C11 hydrocarbons tended to increase. This can be mainly attributed to the decreased Ni-Mo interaction and the increased phosphide particle size. In sum, the structure and performance of Ni-Mo bimetallic phosphide catalyst can be tuned by the calcination temperature of precursor.
文摘Petroleum has played a vital role as the major supplier of materials and energy during the evolution of human civilization.Given the change in demand for energy from high to low carbon and ultimately net zero carbon,the energy framework has undergone revolutionary changes.The energy attribute of petroleum will be gradually weakened,while the material and CO_(2)emission attributes will be gradually strengthened.Thus,the petrochemical processing basis,scientific concepts,and ideas will undergo major adjustments to reshape the petrochemical industry.Hence,it is necessary to reconsider the evolution of the petrochemical industry from a historical perspective and to clarify the historical causes,development contexts,and possible challenges in future development.Herein,we critically reassess the key drivers and rules guiding the development of the petrochemical industry and propose a reconstruction strategy based on simplified engineering thinking,innate nature of energy and material,and CO_(2)emissions,which can be realized through the integration of gasification with CO as the target product and recent C1 chemistry targeting the precise synthesis of chemicals.The concept of the petrochemical industry will change from the product-based process of selection and transformation of raw material molecules to the process of carbon atom reconfiguration driven by product CO_(2)emissions.More accurate management of C atoms can be accomplished with greatly improved utilization efficiency and the reduction of separation intensity and CO_(2)emissions via the stepwise introduction of a new approach in the current petrochemical industry.
基金supported by the CAMS Innovation Fund for Medical Science (2021-I2M-1-034)the National Natural Science Foundation of China (grant number:81700697).
文摘Background:Hypothyroxinemia is a subclinical thyroid hormone deficiency in which the mother has inadequate levels of T_(4) during pregnancy.The fetus relies entirely on the mother's T_(4) hormone level for early neurodevelopment.Isolated maternal hypothyroxinemia(IMH)in the first trimester of pregnancy can lead to lower intelligence,lower motor scores,and a higher risk of mental illness in descendants.Here,we focus on the autism-like behavior of IMH offspring.Methods:The animals were administered 1 ppm of propylthiouracil(PTU)for 9 weeks.Then,the concentrations of T_(3),T_(4),and thyroid-stimulating hormone(TSH)were detected using enzyme-linked immunosorbent assay(ELISA)to verify the developed animal model of IMH.We performed four behavioral experiments,including the marble burying test,open-field test,three-chamber sociability test,and Morris water maze,to explore the autistic-like behavior of 40-day-old offspring rats.Results:The ELISA test showed that the serum T_(3) and TSH concentrations in the model group were normal compared with the negative control group,whereas the T_(4) concentration decreased.In the behavioral experiments,the number of hidden marbles in the offspring of IMH increased significantly,the frequency of entering the central compartment decreased,and the social ratio decreased significantly.Conclusion:The animal model of IMH was developed by the administration of 1 ppm of PTU for 9 weeks,and there were autistic-like behavior changes such as anxiety,weakened social ability,and repeated stereotyping in the IMH offspring by 40 days.
基金the National Natural Science Foundation of China(grant nos.22477054,22122701,22293050,91953201,92153303,22377050)the Natural Science Foundation of Jiangsu Province(grant no.BK20232020)the Excellent Research Program of Nanjing University(grant no.ZYJH004).
文摘The emerging endoplasmic recticulum(ER)crosstalk system demands a more reliable approach for ER-targeting fluorophores to explore ER-associated biochemical species and events.Providing the aromatic sulfonamides’affinity to ATP-sensitive potassium channel protein localized mainly on ER membrane,the sulfonamide fluorophore 4-amino-7-sulfamoylbenzoxadiazole(SBD)was modified to construct ER self-targeting fluorophores without any additional targeting group by alternating the N-substituent structure and numbers of its 4-amino and 7-sulfamoyl groups.The results revealed that a ClogP value over 3.0 endowed those SBDs the ER self-targetability effectively.This provides a strategy to devise an ER-targeting probe by simply modifying the 4-amino group of SBDs as a sensing moiety to make the probe CLogP over 3.0 despite the CLogP value of parent SBDs,and two ER-targeting Zn^(2+)probes ER-SBD-Zn1 and ER-SBD-Zn2 were obtained following this idea.Moreover,ER Zn^(2+)tracking with ER-SBD-Zn1 disclosed for the first time tunicamycin concentration-dependent ER Zn^(2+)fluctuation behavior during ER stress induction.
基金supported by the State Key Laboratory of Catalytic Materials and Reaction Engineering(RIPP,SINOPEC)
文摘Thioetherification between mercaptan and diolefin is an efficient process to remove mercaptans in FCC gasoline at mild condition, during which the selective hydrogenation of diolefin to monoolefin is also expected. Here, Si O2 supported transition metal（Fe, Co, Ni, Mo and W） phosphides were tested for the thioetherification of isoprene and butanethiol on a fixed-bed reactor at 120℃ and 1.5 MPa H2, and their structure before and after reaction was characterized by means of XRD, HRTEM, N2 sorption, CO chemisorption, NH3-TPD, XPS and TG. It was found that, among different metal phosphides, Mo P/Si O2 showed the best performance, and the optimal nominal Mo P loading was 25%. Apart from the nature of metal, the density of metal and acid sites determined the catalyst performance. Metal site was mainly responsible for hydrogenation of isoprene, while acid site dominantly contributed to the thioetherification and the polymerization of olefins. Moreover, a balance between metallic and acidic functions is required to arrive at a desired performance. Excessive metal sites or acid sites led to the over-hydrogenation of isoprene or the severe polymerization of olefins, respectively. 25%Mo P/Si O2 was tested for 37 h time on stream, and butanethiol conversion maintained at 100%; although isoprene conversion remarkably decreased, the selectivity to isopentenes exceeded 80% after reaction for 11 h. We suggest that the deactivation of Mo P/Si O2 is mainly ascribed to the butanethiol poisoning and the carbonaceous deposit, especially the former.
基金This work was financially supported by the National Nature Science Foundation of China(Grant Nos.51922040 and 51821004)the Fok Ying Tung Education Foundation(Grant No.161051)the Fundamental Research Funds for the Central Universities(Nos.2018ZD08 and 2020DF01).
文摘Catalytic steam reforming is a promising route for tar conversion to high energy syngas in the process of biomass gasification. However, the catalyst deactivation caused by the deposition of residual carbon is still a major challenge. In this paper, a modified Ni-based Ni-Co/Al2O3-CaO (Ni-Co/AC) catalyst and a conventional Ni/Al2O3 (Ni/A) catalyst were prepared and tested for tar catalytic removal in which toluene was selected as the model component. Experiments were conducted to reveal the influences of the reaction temperature and the ratio between steam to carbon on the toluene conversion and the hydrogen yield. The physicochemical properties of the modified Ni-based catalyst were determined by a series of characterization methods. The results indicated that the Ni-Co alloy was determined over the Ni-Co/AC catalyst. The doping of CaO and the presence of Ni-Co alloy promoted the performance of toluene catalytic dissociation over Ni-Co/AC catalyst compared with that over Ni/A catalyst. After testing in steam for 40 h, the carbon conversion over Ni-Co/AC maintained above 86% and its resistance to carbon deposition was superior to Ni/A catalyst.
基金The authors gratefully thank the financial support from Excellent CAS Talents(NO.292017312D1100301)Excellent Technology Leader(NO.19XD1433500)Strengthen Industrial Base(GYQJ-2019-1-33)programs,which are from Chinese Academy of Sciences,Science and Technology Commission Shanghai Municipality,and Shanghai Municipal Commission of Economy and Information,respectively.
文摘The 5754 aluminum alloy has been widely used in the automotive industry to reduce the weight of vehicles.The weld-bonding(WB)process comprising resistance spot welding and adhesive bonding processes effectively improves the mechanical properties of joints.However,it is still a great challenge in the WB process to obtain high-quality and defect-free nuggets of aluminum alloys.In this study,the parameters of the WB process are optimized and the mechanism of generation of defects during WB is analyzed.The results show that the welding parameters have a significant effect on the nugget sizes,among which the welding current plays the most important role.The residual adhesive can easily cause defects during welding,e.g.,expulsion and porosity in the nugget.This can be effectively avoided by optimizing the welding parameters.In addition,the gas in the joints is effectively reduced by adding an appropriate preheating pulse prior to welding,thus lowering the damage degree of the adhesive layer.As a result,welded joints with better weld nugget quality and more stable mechanical properties are obtained.
