Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.T...Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.This method spends most of computing time in objective function evaluation by reservoir numerical simulator which limits its optimization efficiency.To improve optimization efficiency,a well production optimization method using streamline features-based objective function and Bayesian adaptive direct search optimization(BADS)algorithm is established.This new objective function,which represents the water flooding potential,is extracted from streamline features.It only needs to call the streamline simulator to run one time step,instead of calling the simulator to calculate the target value at the end of development,which greatly reduces the running time of the simulator.Then the well production optimization model is established and solved by the BADS algorithm.The feasibility of the new objective function and the efficiency of this optimization method are verified by three examples.Results demonstrate that the new objective function is positively correlated with the cumulative oil production.And the BADS algorithm is superior to other common algorithms in convergence speed,solution stability and optimization accuracy.Besides,this method can significantly accelerate the speed of well production optimization process compared with the objective function calculated by other conventional methods.It can provide a more effective basis for determining the optimal well production for actual oilfield development.展开更多
Ion-pair dissociation is an important molecular process and frequently happens when the target molecule is pumped to its electronically superexcited states. In contrast to the experimental studies of photoexcitation i...Ion-pair dissociation is an important molecular process and frequently happens when the target molecule is pumped to its electronically superexcited states. In contrast to the experimental studies of photoexcitation ion-pair dissociation, there are some experimental challenges in the electron-impact ion-pair dissociation study, in particular, on determination of the energetic threshold. Here we report an experimental development for the ion-pair dissociation study by using the monochromized electron impacts. As an example, the threshold of BrCN→Br^-+CN^+ is determined as 13.78 eV according to the appearance energy of CN^+ signals, meanwhile, the time-sliced ion velocity image of CN^+ is recorded at 16.09 eV and indicates an anisotropic distribution of the CN^+ momentum.展开更多
Our experimental progresses on the reaction dynamics of dissociative electron attachment(DEA)to carbon dioxide(CO2)are summarized in this review.First,we introduce some fundamentals about the DEA dynamics and provide ...Our experimental progresses on the reaction dynamics of dissociative electron attachment(DEA)to carbon dioxide(CO2)are summarized in this review.First,we introduce some fundamentals about the DEA dynamics and provide an epitome about the DEAs to CO2.Second,the experimental technique developments are described,in particular,on the highresolution velocity map imaging apparatus in which we put a lot of efforts during the past two years.Third,our findings about the DEA dynamics of CO2 are surveyed and briefly compared with the others’work.At last,we give a perspective about the applications of the DEA studies and highlight the inspirations in the production of molecular oxygen on Mars and the catalytic transformations of CO2.展开更多
Background:The relationship between obstructive sleep apnea (OSA) and platelet reactivity in patients undergoing percutaneous coronary intervention (PCI) has not been defined.The present prospective,single-center...Background:The relationship between obstructive sleep apnea (OSA) and platelet reactivity in patients undergoing percutaneous coronary intervention (PCI) has not been defined.The present prospective,single-center study explored the relationship between platelet reactivity and OSA in patients with PCI.Methods:A total of 242 patients were finally included in the study.OSA was screened overnight by polysomnography.Platelet reactivity was assessed with a sequential platelet counting method,and the platelet maximum aggregation ratio (MAR) and average aggregation ratio were calculated.All patients were assigned per apnea-hypopnea index (AHI) to non-OSA (n =128) and OSA (n =l 14) groups.The receiver operating characteristic curve analysis was used to evaluate the accuracy of AHI for high platelet reactivity (HPR) on aspirin and clopidogrel,and multivariable logistic regression was used to determine the independent predictors of HPR on aspirin and clopidogrel.Results:Median AHI was significantly higher in the OSA group than in the non-OSA group (34.5 events/h vs.8.1 events/h,Z =-13.422,P 〈 0.001).Likewise,median arachidonic acid-and adenosine diphosphate-induced maximum aggregation rate (MAR) in the OSA group was significantly higher than those in the non-OSA group (21.1% vs.17.7%,Z=-3.525,P 〈 0.001 and 45.8% vs.32.2%,Z =-5.708,P 〈 0.001,respectively).Multivariable logistic regression showed that OSA was the only independent predictor for HPR on aspirin (odds ratio [OR]:1.055,95% confidence interval [CI]:1.033-1.077,P 〈 0.001) and clopidogrel (OR:1.036,95% CI:1.017-1.056,P 〈 0.001).The cutoffvalue of AHI for HPR on aspirin was 45.2 events/h (sensitivity 47.1% and specificity 91.3%),whereas cutoffvalue of AHI for HPR on clopidogrel was 21.3 events/h (sensitivity 68.3% and specificity 67.7%).展开更多
Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based...Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based on energy-tunable discharge was employed to deposit suitable amounts of energy to atmospheric pressure pure water vapor for abundant production of water radical cations,stabilized as(H_(2)O)n^(+·)(n=2-5)with a maximal abundance of≥8.3×10^(6) cps for(H_(2)O)_(2)^(+·),characterized by mass spectrometry(MS).The abundance of water radical cations was optimized by adjusting the experimental parameters such as the discharge voltage(2.5 kV),temperature of the MS inlet(140℃),carrier gas flow(20mL/min),and the distance between the discharge tip and MS inlet(12 mm).The ambient formation of water radical cationswas further confirmedby thehigh reactivity of as-prepared water radical cations,which reacted with benzene,ethyl acetate,and dimethyl disulfide instantly,showing rich chemistry with ionic and radical characteristics.Moreover,the computations usingCCSD(T)//MP2 method and density functional theory confirmed that the O-O single-electron bound dimer(B),as well as the hydronium hydroxyl radical complex(A),accounted for the unusual chemistry of the water radical cations,providing a facile approach to access the high reactivity ofwater radical cations under the ambient conditions.展开更多
In this study,a sandwich-type uranium(Ⅵ)-containing silicotungstate KNa11H2(H2O)30[Na(UO2)(SiW9O34)]2·8H2O(1)with new three-dimensional(3D)structure was synthesized and characterized using single-crystal X-ray d...In this study,a sandwich-type uranium(Ⅵ)-containing silicotungstate KNa11H2(H2O)30[Na(UO2)(SiW9O34)]2·8H2O(1)with new three-dimensional(3D)structure was synthesized and characterized using single-crystal X-ray diffraction,Fourier transform infrared,Raman,solid-state ultraviolet–visible diffuse reflection spectra,thermogravimetric analysis and powder X-ray diffraction.Single crystal analysis revealed that the Na(I)-H2O clusters in 1 showed a two-dimensional structure similar to(4,4)-network and resulted in the formation of a new 3D structure of 1.In addition,it was notable that 1 presented excellent catalytic activity for the synthesis of substituted phenylsulfonyl-1H-pyrazoles via the cyclization reaction of 1,3-diketones with various substituted benzenesulfonyl hydrazides.展开更多
Direct aminolysis of selenoester in aqueous media was investigated as a glycopeptide ligation strategy.This strategy allows the peptide and glycopeptide ligation to proceed smoothly(even with hindered amino acids) wit...Direct aminolysis of selenoester in aqueous media was investigated as a glycopeptide ligation strategy.This strategy allows the peptide and glycopeptide ligation to proceed smoothly(even with hindered amino acids) without the need of cysteine residue, N-terminal thiol auxiliary or coupling additive, and to afford the corresponding amide products in excellent yields. No epimerization was observed during ligation reations. In this work, the selenoester of unprotected glycopeptide was readily prepared, and the direct aminolysis of glycopeptide selenoester was successfully applied to synthesize MUC1 mucin sequence efficiently.展开更多
基金supported partly by the National Science and Technology Major Project of China(Grant No.2016ZX05025-001006)Major Science and Technology Project of CNPC(Grant No.ZD2019-183-007)
文摘Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.This method spends most of computing time in objective function evaluation by reservoir numerical simulator which limits its optimization efficiency.To improve optimization efficiency,a well production optimization method using streamline features-based objective function and Bayesian adaptive direct search optimization(BADS)algorithm is established.This new objective function,which represents the water flooding potential,is extracted from streamline features.It only needs to call the streamline simulator to run one time step,instead of calling the simulator to calculate the target value at the end of development,which greatly reduces the running time of the simulator.Then the well production optimization model is established and solved by the BADS algorithm.The feasibility of the new objective function and the efficiency of this optimization method are verified by three examples.Results demonstrate that the new objective function is positively correlated with the cumulative oil production.And the BADS algorithm is superior to other common algorithms in convergence speed,solution stability and optimization accuracy.Besides,this method can significantly accelerate the speed of well production optimization process compared with the objective function calculated by other conventional methods.It can provide a more effective basis for determining the optimal well production for actual oilfield development.
基金supported by the National Natural Science Foundation of China (No.21625301)
文摘Ion-pair dissociation is an important molecular process and frequently happens when the target molecule is pumped to its electronically superexcited states. In contrast to the experimental studies of photoexcitation ion-pair dissociation, there are some experimental challenges in the electron-impact ion-pair dissociation study, in particular, on determination of the energetic threshold. Here we report an experimental development for the ion-pair dissociation study by using the monochromized electron impacts. As an example, the threshold of BrCN→Br^-+CN^+ is determined as 13.78 eV according to the appearance energy of CN^+ signals, meanwhile, the time-sliced ion velocity image of CN^+ is recorded at 16.09 eV and indicates an anisotropic distribution of the CN^+ momentum.
基金supported by the National Natural Science Foundation of China(No.21727804,No.21625301,No.21273213)。
文摘Our experimental progresses on the reaction dynamics of dissociative electron attachment(DEA)to carbon dioxide(CO2)are summarized in this review.First,we introduce some fundamentals about the DEA dynamics and provide an epitome about the DEAs to CO2.Second,the experimental technique developments are described,in particular,on the highresolution velocity map imaging apparatus in which we put a lot of efforts during the past two years.Third,our findings about the DEA dynamics of CO2 are surveyed and briefly compared with the others’work.At last,we give a perspective about the applications of the DEA studies and highlight the inspirations in the production of molecular oxygen on Mars and the catalytic transformations of CO2.
基金The present trial was supported by grants from the National Science Foundation of China (No. NSFC 81770342), Nanjing Health and Family Planning Commission (No. YKK16124), and Nanjing Municipal Commission of Science and Technology (No. 201715026).
文摘Background:The relationship between obstructive sleep apnea (OSA) and platelet reactivity in patients undergoing percutaneous coronary intervention (PCI) has not been defined.The present prospective,single-center study explored the relationship between platelet reactivity and OSA in patients with PCI.Methods:A total of 242 patients were finally included in the study.OSA was screened overnight by polysomnography.Platelet reactivity was assessed with a sequential platelet counting method,and the platelet maximum aggregation ratio (MAR) and average aggregation ratio were calculated.All patients were assigned per apnea-hypopnea index (AHI) to non-OSA (n =128) and OSA (n =l 14) groups.The receiver operating characteristic curve analysis was used to evaluate the accuracy of AHI for high platelet reactivity (HPR) on aspirin and clopidogrel,and multivariable logistic regression was used to determine the independent predictors of HPR on aspirin and clopidogrel.Results:Median AHI was significantly higher in the OSA group than in the non-OSA group (34.5 events/h vs.8.1 events/h,Z =-13.422,P 〈 0.001).Likewise,median arachidonic acid-and adenosine diphosphate-induced maximum aggregation rate (MAR) in the OSA group was significantly higher than those in the non-OSA group (21.1% vs.17.7%,Z=-3.525,P 〈 0.001 and 45.8% vs.32.2%,Z =-5.708,P 〈 0.001,respectively).Multivariable logistic regression showed that OSA was the only independent predictor for HPR on aspirin (odds ratio [OR]:1.055,95% confidence interval [CI]:1.033-1.077,P 〈 0.001) and clopidogrel (OR:1.036,95% CI:1.017-1.056,P 〈 0.001).The cutoffvalue of AHI for HPR on aspirin was 45.2 events/h (sensitivity 47.1% and specificity 91.3%),whereas cutoffvalue of AHI for HPR on clopidogrel was 21.3 events/h (sensitivity 68.3% and specificity 67.7%).
基金supported by a grant from the National Natural Science Foundation of China(grant no.215201-02007)the US National Science Foundation(grant no.1905087).
文摘Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based on energy-tunable discharge was employed to deposit suitable amounts of energy to atmospheric pressure pure water vapor for abundant production of water radical cations,stabilized as(H_(2)O)n^(+·)(n=2-5)with a maximal abundance of≥8.3×10^(6) cps for(H_(2)O)_(2)^(+·),characterized by mass spectrometry(MS).The abundance of water radical cations was optimized by adjusting the experimental parameters such as the discharge voltage(2.5 kV),temperature of the MS inlet(140℃),carrier gas flow(20mL/min),and the distance between the discharge tip and MS inlet(12 mm).The ambient formation of water radical cationswas further confirmedby thehigh reactivity of as-prepared water radical cations,which reacted with benzene,ethyl acetate,and dimethyl disulfide instantly,showing rich chemistry with ionic and radical characteristics.Moreover,the computations usingCCSD(T)//MP2 method and density functional theory confirmed that the O-O single-electron bound dimer(B),as well as the hydronium hydroxyl radical complex(A),accounted for the unusual chemistry of the water radical cations,providing a facile approach to access the high reactivity ofwater radical cations under the ambient conditions.
基金supported by the National Natural Science Foundation of China (Grant No. 22001034)the Open Fund of the Jiangxi Province Key Laboratory of Synthetic Chemistry (Grant No. JXSC202008)the Research Found of East China University of Technology (Grant Nos. DHBK2019264, DHBK2019265, DHBK2019267)
文摘In this study,a sandwich-type uranium(Ⅵ)-containing silicotungstate KNa11H2(H2O)30[Na(UO2)(SiW9O34)]2·8H2O(1)with new three-dimensional(3D)structure was synthesized and characterized using single-crystal X-ray diffraction,Fourier transform infrared,Raman,solid-state ultraviolet–visible diffuse reflection spectra,thermogravimetric analysis and powder X-ray diffraction.Single crystal analysis revealed that the Na(I)-H2O clusters in 1 showed a two-dimensional structure similar to(4,4)-network and resulted in the formation of a new 3D structure of 1.In addition,it was notable that 1 presented excellent catalytic activity for the synthesis of substituted phenylsulfonyl-1H-pyrazoles via the cyclization reaction of 1,3-diketones with various substituted benzenesulfonyl hydrazides.
基金supported by the National Key Research and Development Program of China (No. 2017YFA0505200)the National Natural Science Foundation of China (No. 21772056)+2 种基金Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation Open Foundation (No. JXMS201701)the self-determined research funds of CCNU from the colleges' basic research and operation of MOE (No. CCNU18TS011)the Program of Introducing Talents of Discipline to Universities of China(111 program, No. B17019)
文摘Direct aminolysis of selenoester in aqueous media was investigated as a glycopeptide ligation strategy.This strategy allows the peptide and glycopeptide ligation to proceed smoothly(even with hindered amino acids) without the need of cysteine residue, N-terminal thiol auxiliary or coupling additive, and to afford the corresponding amide products in excellent yields. No epimerization was observed during ligation reations. In this work, the selenoester of unprotected glycopeptide was readily prepared, and the direct aminolysis of glycopeptide selenoester was successfully applied to synthesize MUC1 mucin sequence efficiently.