Electrochemical micromachining （EMM） technology for fabricating micro structures is presented in this article. By applying ultra short pulses, dissolution of a workpiece can be restricted to the region very close to...Electrochemical micromachining （EMM） technology for fabricating micro structures is presented in this article. By applying ultra short pulses, dissolution of a workpiece can be restricted to the region very close to the electrode. First, an EMM system for meeting the requirements of the EMM process is established. Second, sets of experiments is carried out to investigate the influence of some of the predominant electrochemical process parameters such as electrical parameters, feed rate, electrode geometry features and electrolyte composition on machining quality, especially the influences of pulse on time on shape precision and working end shape of electrode on machined surface quality. Finally, after the preliminary experiments, a complex microstructure with good shape precision and surface quality is successfully obtained.展开更多
Simulation for stochastic wind field is very important in analyzing dynamic responses of large complex structures due to strong wind.The typical simulation method is the spectrum representation method (SRM),but the SR...Simulation for stochastic wind field is very important in analyzing dynamic responses of large complex structures due to strong wind.The typical simulation method is the spectrum representation method (SRM),but the SRM has drawbacks of inferior precision in lower frequency and slow calculating speed.In view of this,the modified Fourier spectrum method (MFSM) is introduced into the simulation of stochastic wind field in this paper.In this method,phase information of wind velocity time history is determined by cross power spectral density (CPSD) between adjacent points,and the wind velocity time history with time and space correlation is generated by iterative modification for CPSD considering auto power spectral density (APSD).Simulation of the wind field for a long-span bridge is undertaken to verify the effectiveness of the MFSM.Simulation results of the SRM and the MFSM are compared.It can be concluded that the MFSM is more accurate and has higher calculation speed than the SRM.展开更多
Electromagnetic logging while drilling(LWD)is one of the key technologies of the geosteering and formation evaluation for high-angle and horizontal wells.In this paper,we solve the dipole source-generated magnetic/ele...Electromagnetic logging while drilling(LWD)is one of the key technologies of the geosteering and formation evaluation for high-angle and horizontal wells.In this paper,we solve the dipole source-generated magnetic/electric fields in 2D formations efficiently by the 2.5D finite diff erence method.Particularly,by leveraging the field’s rapid attenuation in spectral domain,we propose truncated Gauss–Hermite quadrature,which is several tens of times faster than traditional inverse fast Fourier transform.By applying the algorithm to the LWD modeling under complex formations,e.g.,folds,fault and sandstone pinch-outs,we analyze the feasibility of the dimension reduction from 2D to 1D.For the formations with smooth lateral changes,like folds,the simplified 1D model’s results agree well with the true responses,which indicate that the 1D simplification with sliding window is feasible.However,for the formation structures with drastic rock properties changes and sharp boundaries,for instance,faults and sandstone pinch-outs,the simplified 1D model will lead to large errors and,therefore,2.5D algorithms should be applied to ensure the accuracy.展开更多
The main purpose of this note is to construct almost complex or complex structures on certain isoparametric hypersurfaces in unit spheres.As a consequence,complex structures on S^(1)×S^(7)×S^(6),and on S^(10...The main purpose of this note is to construct almost complex or complex structures on certain isoparametric hypersurfaces in unit spheres.As a consequence,complex structures on S^(1)×S^(7)×S^(6),and on S^(10)×S^(3)×S(2)with vanishing first Chern class,are built.展开更多
This paper presents the relations between spinors and dual characteristic pairs, and gives a way to get the dual characteristic pairs of Dirac structure associated to a generalized complex structure.
Traditionally, simplification has been used in scientific modeling practices. However, recent advancements in deep learning techniques have provided a means to represent complex models. As a result, deep neural networ...Traditionally, simplification has been used in scientific modeling practices. However, recent advancements in deep learning techniques have provided a means to represent complex models. As a result, deep neural networks should be able to approximate the complex models, with a high degree of generalization. To achieve generalization, it is necessary to have a diverse range of examples in the training of the neural network, for example in data-driven FWI, training data should cover the expected subsurface models. To meet this requirement, we porposed a method to create geologically meaningful velocity models with complex structures and severe topography. However, it is important to note that generalization comes with its own set of challenges.Because of significant variation in topography of the generated velocity models, we need to include this information as an additional input data in training of the network. Therefore, we have transformed the seismic data to a fixed datum to incorporate geometric information. Additionally, we have enhanced the network's performance by introducing a term in the network loss function. Multiple metrics have been employed to evaluate the performance of the network. The results indicate that by providing the necessary information to the network and employing computational techniques to refine the model's accuracy, deep neural networks are capable of accurately estimating velocity models in complex environments characterized by extreme topography.展开更多
The Reliability-Based Design Optimization(RBDO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount ...The Reliability-Based Design Optimization(RBDO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount of sampling simulation computation.In this paper,a basis-adaptive Polynomial Chaos(PC)-Kriging surrogate model is proposed,in order to relieve the computational burden and enhance the predictive accuracy of a metamodel.The active learning basis-adaptive PC-Kriging model is combined with a quantile-based RBDO framework.Finally,five engineering cases have been implemented,including a benchmark RBDO problem,three high-dimensional explicit problems,and a high-dimensional implicit problem.Compared with Support Vector Regression(SVR),Kriging,and polynomial chaos expansion models,results show that the proposed basis-adaptive PC-Kriging model is more accurate and efficient for RBDO problems of complex engineering structures.展开更多
In this paper,we introduce the notion of a product structure on a 3-Bihom-Lie algebra,which is a Nijenhuis operator with some conditions.We prove that a 3-Bihom-Lie algebra has a product structure if and only if it is...In this paper,we introduce the notion of a product structure on a 3-Bihom-Lie algebra,which is a Nijenhuis operator with some conditions.We prove that a 3-Bihom-Lie algebra has a product structure if and only if it is the direct sum of two vector spaces which are also Bihom-subalgebras.Then we give four special conditions under each of which a 3-Bihom-Lie algebra has a special decomposition.Similarly,we introduce a complex structure on a 3-Bihom-Lie algebra and there are also four types of special complex structures.Finally,we establish the relation between a complex structure and a product structure.展开更多
We calculate the dimensions of Bott–Chern and Aeppli cohomologies associated to a complex structure on S^(3)×S^(3).We express them in terms mainly of Hogde numbers.
As a matter of fact,most natural structures are complex topology structures with intricate holes or irregular surface morphology.These structures can be used as lightweight infill,porous scaffold,energy absorber or mi...As a matter of fact,most natural structures are complex topology structures with intricate holes or irregular surface morphology.These structures can be used as lightweight infill,porous scaffold,energy absorber or micro-reactor.With the rapid advancement of 3D printing,the complex topology structures can now be efficiently and accurately fabricated by stacking layered materials.The novel manufacturing technology and application background put forward new demands and challenges to the current design methodologies of complex topology structures.In this paper,a brief review on the development of recent complex topology structure design methods was provided;meanwhile,the limitations of existing methods and future work are also discussed in the end.展开更多
Two new fluorinated phenylisoquinoline-based iridium（Ⅲ） complexes,[Ir（f2piq）2（bipy）][PF6]（3a） and[Ir（fmpiq）2（bipy）][PF6]（3b）（f2piq = l-（2,4-difluorophenyl）isoquinoline,fmpiq = 1-（4-fluoro-2-methylph...Two new fluorinated phenylisoquinoline-based iridium（Ⅲ） complexes,[Ir（f2piq）2（bipy）][PF6]（3a） and[Ir（fmpiq）2（bipy）][PF6]（3b）（f2piq = l-（2,4-difluorophenyl）isoquinoline,fmpiq = 1-（4-fluoro-2-methylphenyl）isoquinoline,bipy = 2,2＇-bipyridine）,have been synthesized and fully characterized.Single crystal X-ray diffraction study has been undertaken on complexes 3a and 3b,which show that each adopts the distorted octahedral coordination geometry with the cis-C,C＇ and trans-N,N＇ configuration.The photoluminescence spectra of 3a and 3b exhibit yellow and orange emission maxima at 584 and 600 nm,respectively.The frontier molecular orbital diagrams and the lowest-energy electronic transitions of 3a-3b have been calculated with density functional theory（DFT） and time-dependent DFT（TD-DFT）.The absorption and emission spectra of complex 3b is red-shifted relative to those of complex 3a,as a consequence of the nature of the methyl group.展开更多
The two complexes [HgI_2L]（DMF）（1） and [AgL_2]（ClO_4）（CH_3CN）（2） were synthesized from the reaction of Schiff base ligand（2-acetylpyridine-p-aminobenzoylhydrazone）（L） with HgI_2 or AgClO_4 respectively. ...The two complexes [HgI_2L]（DMF）（1） and [AgL_2]（ClO_4）（CH_3CN）（2） were synthesized from the reaction of Schiff base ligand（2-acetylpyridine-p-aminobenzoylhydrazone）（L） with HgI_2 or AgClO_4 respectively. The compounds are characterized by ^1H NMR,FTIR and elemental analysis. The structures of the ligand and two complexes are measured via single-crystal X-ray diffraction. In these two complexes,the structures are both distorted triangular bipyramids with five-coordinated centers.展开更多
A new kind of Schiff base HL（HL= 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-Leucine methyl ester） and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2（L′ = 1-phenyl-3-methyl-4-（p-meth...A new kind of Schiff base HL（HL= 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-Leucine methyl ester） and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2（L′ = 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-leucine ethyl,L′′ = 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-leucine） have been synthesized and structurally determined by X-ray diffraction. For HL： crystal structure determination indicates that there are two independent HLs with different conformations in one asymmetric unit. For complex 1： the Ni（Ⅱ） ion is six-coordinated by two carbonyl oxygen atoms from pyrazolone ring,two nitrogen atoms from different HL′ and two oxygen atoms from L-Leucine ethyl ester to form a distorted octahedral geometry. For complex 2： the Cu（Ⅱ） ion is four-coordinated by one carbonyl oxygen atom from the pyrazolone ring,one nitrogen atom from HL′′,and two different carboxylic oxygen atoms from L-leucine with the same conformation to form a distorted quadrilateral geometry.展开更多
The mononuclear radical anionic complex [1-N-methyl-1,10-phenanthrolium][Ni（dmit）2]（dmit = 1,3-dithiole-2-thione-4,5-dithiolate） with a new countercation has been prepared and its crystal structure was determined ...The mononuclear radical anionic complex [1-N-methyl-1,10-phenanthrolium][Ni（dmit）2]（dmit = 1,3-dithiole-2-thione-4,5-dithiolate） with a new countercation has been prepared and its crystal structure was determined by X-ray crystallography at 298 and 80 K. In the mononuclear radical anionic complex, the nickel ion assumes a slightly distorted square-planar geometry. There are two and three kinds of intermolecular interactions between adjacent mononuclear radical anionic complexes in the crystal at 298 and 80 K, respectively（i.e., Models A and B at 298 K; and Models C, D and E at 80 K）. The variable-temperature magnetic moments indicate a strong antiferromagnetic interaction between the adjacent mononuclear radical anionic complexes, and the theoretical calculations reveal that the stronger antiferromagnetic coupling strength at lower temperature should be contributed to the larger overlap integrals between the short contact atoms. This study is the first to reveal the mechanism of stronger magnetic coupling strength at lower temperature for a mononuclear radical anionic nickel complex with dmit as the ligand.展开更多
The two title complexes, [Cd{3,5-（NO2）2sal}（2,2′-bipy）]n 1 and [Mn{3,5- （NO2）2sal}（2,2′-bipy）]n 2 （3,5-（NO2）2sal = 3,5-dinitrosalicylate, 2,2＇-bipy = 2,2′-bipyridine）, were synthesized by the hydrother...The two title complexes, [Cd{3,5-（NO2）2sal}（2,2′-bipy）]n 1 and [Mn{3,5- （NO2）2sal}（2,2′-bipy）]n 2 （3,5-（NO2）2sal = 3,5-dinitrosalicylate, 2,2＇-bipy = 2,2′-bipyridine）, were synthesized by the hydrothermal reaction and structurally characterized. Complex 1 crystallizes in triclinic, space group P1, a = 5.581（4）, b = 12.071（8）, c = 12.88（1）A, α= 92.10（3）,β= 96.73（3）, γ = 102.02（2）°, C17H10N407Cd, Mr = 494.69, V= 841（1）A3, Z = 2, Dc = 1.954 g/cm3, F（000） = 488, μ= 1.353 mm^-1, R = 0.0248 and wR = 0.0761. Complex 2 crystallizes in monoclinic with space group P21/c, a = 8.604（3）, b = 23.88（1）, c = 8.894（3） A, β = 102.45（1）°, C17H10N407Mn, Mr = 437.23, V= 1785（1） A3, Z=.4, Dc = 1.627 g/cm3, F（000） = 884, μ = 0.791 mm^-1, R = 0.0471 and wR = 0.1250. Complex 1 possesses an infinite 1D polymeric chain structure consisting of the repeated basic four-membered ring units （Cd2O2） and eight-membered ring units （CdOCO）2. Compound 2displays a linear 1D chain through Mn（Ⅱ） atoms and bridging carboxylate groups of 3,5-dinitrosalicylic acid ligands with the Mn…Mn separation of 4.472（2）A. The fluorescence properties and cyclic voltammetric behaviors of the complexes are also reported.展开更多
Eight new ZnⅡ-yⅢ and ZnⅡ-LnⅢ heterometallic Schiff base complexes： MZnL2（NO3）3 （M = Y （1）, La （2）, Pr （3）, Nd （4）, Eu （5）, Gd （6）, Dy （7）, Er （8）; L = 2-（（（2- （imidazo[1,5-a]pyridin-3-yl）p...Eight new ZnⅡ-yⅢ and ZnⅡ-LnⅢ heterometallic Schiff base complexes： MZnL2（NO3）3 （M = Y （1）, La （2）, Pr （3）, Nd （4）, Eu （5）, Gd （6）, Dy （7）, Er （8）; L = 2-（（（2- （imidazo[1,5-a]pyridin-3-yl）phenyl）imino）methyl）-6-methoxyphenol）, have been rationally synthesized under solvothermal conditions and characterized by IR, elemental analyses （EA）, single-crystal X-ray diffraction, and powder XRD. Furthermore, luminescence in the visible region for solids 1-8 suggested zine/ligand-centered emission at room temperature.展开更多
An efficient method for the synthesis of some difunctionalized copillar[5]arene Schiff bases from condensation of salicylaldehyde and its 5-chloro,5-bromo,3,5-di（t-butyl） substituted derivatives with corresponding d...An efficient method for the synthesis of some difunctionalized copillar[5]arene Schiff bases from condensation of salicylaldehyde and its 5-chloro,5-bromo,3,5-di（t-butyl） substituted derivatives with corresponding diamino-functionalized copillar[5]arene,which were prepared by Gabriel reaction according to the reported method.Single-crystals of six copillar[5]arenes were determined by X-ray diffraction.An ORTEP of compounds showed that the two chains units of Schiff base exist in the outside of the cavity of pillar[5]arene.Furthermore,the complexing ability of these Schiff bases to transition metal ions were investigated by UV and fluorescence spectroscopy.展开更多
The crystal structure of the title complex salt has been determined by single-crystal X-ray structure analysis. The crystal data are as follows; Monoclinic, P21/c, a=15.6480(10)A,b=16.7870(10)A, c=10.347(2)A, β=90.79...The crystal structure of the title complex salt has been determined by single-crystal X-ray structure analysis. The crystal data are as follows; Monoclinic, P21/c, a=15.6480(10)A,b=16.7870(10)A, c=10.347(2)A, β=90.790(10), V=2717.7(6)A3, Z=3, and R=0.0333 for 4789 unique reflections. The complex anion has a pseudo-octahedral structure distorted more than the CrⅢand CoⅢ analogs, in which cach iminodiacetato ligand (ida2-) is coordinated in a facial fashion with the two N atoms in a cis configuration, resulting in an unsyin-fac structure.展开更多
The reactivity of carbonyl iron cluster with alkynes has been studied by the thermal reaction of Fe_3（CO）_（12） with R-C≡C-R＇（R = Fc（Ferrocenyl）; R′ = Ph（Phenyl）, Fc, H）. The hexacarbonyldiiron cluster wit...The reactivity of carbonyl iron cluster with alkynes has been studied by the thermal reaction of Fe_3（CO）_（12） with R-C≡C-R＇（R = Fc（Ferrocenyl）; R′ = Ph（Phenyl）, Fc, H）. The hexacarbonyldiiron cluster with ferracyclopentadiene ring（μ_2, η~4-C_4Ph_4）Fe_2（CO）_6（1） and one tetraphenyl substituted cyclopentadienone（Ph_4C_4CO）（2） were simultaneously obtained by the reaction of Fe_3（CO）_（12） with alkyne（Ph-C≡C-Ph）. Only one ferrole cluster（μ_2, η~4-C_4Fc_2H_2）Fe_2（CO）_6（3） was separated by using Fc-C≡C-H as alkyne. One tri-carbonyl iron complex（η~4-C_4Fc_4CO）Fe（CO）_3（4） and an unexpected new cyclic ketone compound 2,2,4,5-tetraferrocenylcyclopenta-4-en-1,3-di-one [Fc_4C_3（CO）_2]（5） were obtained by using Fc-C≡C-Fc as alkyne. A new complex（η4-2,4-diphenyl-3,5-diferrocenylcyclopenta-2,4-dien-1-one）-tricarbonyl iron（η~4-C_4Ph_2Fc_2CO）Fe（CO）_3（6） was synthesized by the reaction of Fe_3（CO）_（12） with Fc-C≡C-Ph. The structures of compounds 1~6 were determined by X-ray single-crystal diffraction and spectroscopic characterization. The crystal structures of two new compounds 5 and 6 were analyzed. Our experimental results reveal the structural models of the reaction products are affected by the kinds of substituents from alkynes R-C≡C-R′.展开更多
The northern Sichuan Basin,spreading in the northern section of the Longmenshan Fault Fold Belt,is characterized by dramatic fluctuations in the surface landforms,development of abdominal faults,and low-quality seismi...The northern Sichuan Basin,spreading in the northern section of the Longmenshan Fault Fold Belt,is characterized by dramatic fluctuations in the surface landforms,development of abdominal faults,and low-quality seismic data,resulting in difficulties in clarifying relevant structures.The key target formation,the Mid-Permian Qixia Fm,is deeply buried with thin reservoirs and high heterogeneity,which brings great challenges to seismic prediction.Under such circumstances,researches have been conducted jointly in terms of seismic data acquisition,processing and interpretation,and finally some relevant seismic survey technologies were developed suitable for surface/underground complex structures.Through surface structural surveys,dynamic deep-well lithologic identification,single-point detector deployment and process optimization,acquisition parameters can be excited.In addition,by using an observation systemwith high-coverage,wide-azimuth and huge-displacement,quality of acquired seismic data can be enhanced dramatically.Seismic imaging technologies for complex structures have been developed to enhance the quality of images for deep formations.These technologies are dominated by microscopic logging-constrained tomography static correction,high-resolution processing with fidelity and amplitude preservation and all-around PSDM in an angular domain.By using high-resolution gravity,magnetic and electric data,details related to geological structures and faults can be identified.In combination with fine seismic data interpretation,structural details and fault features can be verified effectively.Based on forwardmodeling and fine seismic calibration of reservoirs in individualwells,suitable attributes can be identified for predictions related to the distribution of reservoirs.By using all these auxiliary technologies,a large-scale structuralelithologic composite trap with a total area of 1223 km^(2) has been discovered in the NW Sichuan Basin.The Shuangyushi-Jiangyou area as a whole distributes on structural highs.In the areas to the south of Shuangyushi,the Qixia Fm dolomite reservoirs of platform margins are continuously developed.In conclusion,these auxiliary technologies can effectively allow trap identification and thin reservoir prediction in complex structures in the study area.In addition to clarifying the exploration orientation and providing a necessarily technical supports forwell development,these technologies help to accelerate the construction of demonstration projects for the exploration and development of deep marine carbonate formations.展开更多
基金National Natural Science Foundation of China (50635040)National High-tech Research and Development Program (2009AA04Z302)Jiangsu Provincial Natural Science Foundation (BK2008043)
文摘Electrochemical micromachining （EMM） technology for fabricating micro structures is presented in this article. By applying ultra short pulses, dissolution of a workpiece can be restricted to the region very close to the electrode. First, an EMM system for meeting the requirements of the EMM process is established. Second, sets of experiments is carried out to investigate the influence of some of the predominant electrochemical process parameters such as electrical parameters, feed rate, electrode geometry features and electrolyte composition on machining quality, especially the influences of pulse on time on shape precision and working end shape of electrode on machined surface quality. Finally, after the preliminary experiments, a complex microstructure with good shape precision and surface quality is successfully obtained.
基金Project supported by the National Natural Science Foundation of China (No.90915004)the Six Talents Peak in Jiangsu Province(No.2008178)the 333 High-Level Talent Training Project of Jiangsu Province,China
文摘Simulation for stochastic wind field is very important in analyzing dynamic responses of large complex structures due to strong wind.The typical simulation method is the spectrum representation method (SRM),but the SRM has drawbacks of inferior precision in lower frequency and slow calculating speed.In view of this,the modified Fourier spectrum method (MFSM) is introduced into the simulation of stochastic wind field in this paper.In this method,phase information of wind velocity time history is determined by cross power spectral density (CPSD) between adjacent points,and the wind velocity time history with time and space correlation is generated by iterative modification for CPSD considering auto power spectral density (APSD).Simulation of the wind field for a long-span bridge is undertaken to verify the effectiveness of the MFSM.Simulation results of the SRM and the MFSM are compared.It can be concluded that the MFSM is more accurate and has higher calculation speed than the SRM.
基金the National Natural Science Foundation of China (41674131,41574118,41974146,41904109)the Fundamental Research Funds for the Central Universities (17CX06041,17CX06044)the China National Science and Technology Major Project (2016ZX05007-004,2017ZX05072-002)
文摘Electromagnetic logging while drilling(LWD)is one of the key technologies of the geosteering and formation evaluation for high-angle and horizontal wells.In this paper,we solve the dipole source-generated magnetic/electric fields in 2D formations efficiently by the 2.5D finite diff erence method.Particularly,by leveraging the field’s rapid attenuation in spectral domain,we propose truncated Gauss–Hermite quadrature,which is several tens of times faster than traditional inverse fast Fourier transform.By applying the algorithm to the LWD modeling under complex formations,e.g.,folds,fault and sandstone pinch-outs,we analyze the feasibility of the dimension reduction from 2D to 1D.For the formations with smooth lateral changes,like folds,the simplified 1D model’s results agree well with the true responses,which indicate that the 1D simplification with sliding window is feasible.However,for the formation structures with drastic rock properties changes and sharp boundaries,for instance,faults and sandstone pinch-outs,the simplified 1D model will lead to large errors and,therefore,2.5D algorithms should be applied to ensure the accuracy.
基金The project is partially supported by the NSFC(11871282,11931007)BNSF(Z190003)Nankai Zhide Foundation.
文摘The main purpose of this note is to construct almost complex or complex structures on certain isoparametric hypersurfaces in unit spheres.As a consequence,complex structures on S^(1)×S^(7)×S^(6),and on S^(10)×S^(3)×S(2)with vanishing first Chern class,are built.
基金Supported by the Science and Technology Project of Beijing Municipal Commission of Education（SQKM201211232017） Supported by the National Science Foundation of China（Ill26152）
文摘This paper presents the relations between spinors and dual characteristic pairs, and gives a way to get the dual characteristic pairs of Dirac structure associated to a generalized complex structure.
文摘Traditionally, simplification has been used in scientific modeling practices. However, recent advancements in deep learning techniques have provided a means to represent complex models. As a result, deep neural networks should be able to approximate the complex models, with a high degree of generalization. To achieve generalization, it is necessary to have a diverse range of examples in the training of the neural network, for example in data-driven FWI, training data should cover the expected subsurface models. To meet this requirement, we porposed a method to create geologically meaningful velocity models with complex structures and severe topography. However, it is important to note that generalization comes with its own set of challenges.Because of significant variation in topography of the generated velocity models, we need to include this information as an additional input data in training of the network. Therefore, we have transformed the seismic data to a fixed datum to incorporate geometric information. Additionally, we have enhanced the network's performance by introducing a term in the network loss function. Multiple metrics have been employed to evaluate the performance of the network. The results indicate that by providing the necessary information to the network and employing computational techniques to refine the model's accuracy, deep neural networks are capable of accurately estimating velocity models in complex environments characterized by extreme topography.
基金supported by the National Key R&D Program of China(No.2021YFB1715000)the National Natural Science Foundation of China(No.52375073)。
文摘The Reliability-Based Design Optimization(RBDO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount of sampling simulation computation.In this paper,a basis-adaptive Polynomial Chaos(PC)-Kriging surrogate model is proposed,in order to relieve the computational burden and enhance the predictive accuracy of a metamodel.The active learning basis-adaptive PC-Kriging model is combined with a quantile-based RBDO framework.Finally,five engineering cases have been implemented,including a benchmark RBDO problem,three high-dimensional explicit problems,and a high-dimensional implicit problem.Compared with Support Vector Regression(SVR),Kriging,and polynomial chaos expansion models,results show that the proposed basis-adaptive PC-Kriging model is more accurate and efficient for RBDO problems of complex engineering structures.
基金Supported by NNSF of China(No.12271085 and No.12071405)supported by Sichuan Science and Technology Program(No.2023NSFSC1287).
文摘In this paper,we introduce the notion of a product structure on a 3-Bihom-Lie algebra,which is a Nijenhuis operator with some conditions.We prove that a 3-Bihom-Lie algebra has a product structure if and only if it is the direct sum of two vector spaces which are also Bihom-subalgebras.Then we give four special conditions under each of which a 3-Bihom-Lie algebra has a special decomposition.Similarly,we introduce a complex structure on a 3-Bihom-Lie algebra and there are also four types of special complex structures.Finally,we establish the relation between a complex structure and a product structure.
文摘We calculate the dimensions of Bott–Chern and Aeppli cohomologies associated to a complex structure on S^(3)×S^(3).We express them in terms mainly of Hogde numbers.
基金supported by Science Fund for Creative Research Groups of National Natural Science Foundation of China(No.51521064)the National Nature Science Foundation of China(No.51575483).
文摘As a matter of fact,most natural structures are complex topology structures with intricate holes or irregular surface morphology.These structures can be used as lightweight infill,porous scaffold,energy absorber or micro-reactor.With the rapid advancement of 3D printing,the complex topology structures can now be efficiently and accurately fabricated by stacking layered materials.The novel manufacturing technology and application background put forward new demands and challenges to the current design methodologies of complex topology structures.In this paper,a brief review on the development of recent complex topology structure design methods was provided;meanwhile,the limitations of existing methods and future work are also discussed in the end.
基金supported by the National Natural Science Foundation of China(No.21501037)the Natural Science Foundation of Hainan Province(No.20152017)the Science and Research Project of Education Department of Hainan Province(Nos.Hjkj2013-25 and Hnky2015-27)
文摘Two new fluorinated phenylisoquinoline-based iridium（Ⅲ） complexes,[Ir（f2piq）2（bipy）][PF6]（3a） and[Ir（fmpiq）2（bipy）][PF6]（3b）（f2piq = l-（2,4-difluorophenyl）isoquinoline,fmpiq = 1-（4-fluoro-2-methylphenyl）isoquinoline,bipy = 2,2＇-bipyridine）,have been synthesized and fully characterized.Single crystal X-ray diffraction study has been undertaken on complexes 3a and 3b,which show that each adopts the distorted octahedral coordination geometry with the cis-C,C＇ and trans-N,N＇ configuration.The photoluminescence spectra of 3a and 3b exhibit yellow and orange emission maxima at 584 and 600 nm,respectively.The frontier molecular orbital diagrams and the lowest-energy electronic transitions of 3a-3b have been calculated with density functional theory（DFT） and time-dependent DFT（TD-DFT）.The absorption and emission spectra of complex 3b is red-shifted relative to those of complex 3a,as a consequence of the nature of the methyl group.
基金Supported by the National Natural Science Foundation of China(No.21061003)
文摘The two complexes [HgI_2L]（DMF）（1） and [AgL_2]（ClO_4）（CH_3CN）（2） were synthesized from the reaction of Schiff base ligand（2-acetylpyridine-p-aminobenzoylhydrazone）（L） with HgI_2 or AgClO_4 respectively. The compounds are characterized by ^1H NMR,FTIR and elemental analysis. The structures of the ligand and two complexes are measured via single-crystal X-ray diffraction. In these two complexes,the structures are both distorted triangular bipyramids with five-coordinated centers.
文摘A new kind of Schiff base HL（HL= 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-Leucine methyl ester） and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2（L′ = 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-leucine ethyl,L′′ = 1-phenyl-3-methyl-4-（p-methylbenzoyl）-5-pyrazolone with L-leucine） have been synthesized and structurally determined by X-ray diffraction. For HL： crystal structure determination indicates that there are two independent HLs with different conformations in one asymmetric unit. For complex 1： the Ni（Ⅱ） ion is six-coordinated by two carbonyl oxygen atoms from pyrazolone ring,two nitrogen atoms from different HL′ and two oxygen atoms from L-Leucine ethyl ester to form a distorted octahedral geometry. For complex 2： the Cu（Ⅱ） ion is four-coordinated by one carbonyl oxygen atom from the pyrazolone ring,one nitrogen atom from HL′′,and two different carboxylic oxygen atoms from L-leucine with the same conformation to form a distorted quadrilateral geometry.
基金supported by the National Natural Science Foundation of China(No.20971080)the Natural Science Foundation of Shandong Province(No.ZR2013BM009)
文摘The mononuclear radical anionic complex [1-N-methyl-1,10-phenanthrolium][Ni（dmit）2]（dmit = 1,3-dithiole-2-thione-4,5-dithiolate） with a new countercation has been prepared and its crystal structure was determined by X-ray crystallography at 298 and 80 K. In the mononuclear radical anionic complex, the nickel ion assumes a slightly distorted square-planar geometry. There are two and three kinds of intermolecular interactions between adjacent mononuclear radical anionic complexes in the crystal at 298 and 80 K, respectively（i.e., Models A and B at 298 K; and Models C, D and E at 80 K）. The variable-temperature magnetic moments indicate a strong antiferromagnetic interaction between the adjacent mononuclear radical anionic complexes, and the theoretical calculations reveal that the stronger antiferromagnetic coupling strength at lower temperature should be contributed to the larger overlap integrals between the short contact atoms. This study is the first to reveal the mechanism of stronger magnetic coupling strength at lower temperature for a mononuclear radical anionic nickel complex with dmit as the ligand.
基金the National Natural Science Foundation of China (No. 20431010)
文摘The two title complexes, [Cd{3,5-（NO2）2sal}（2,2′-bipy）]n 1 and [Mn{3,5- （NO2）2sal}（2,2′-bipy）]n 2 （3,5-（NO2）2sal = 3,5-dinitrosalicylate, 2,2＇-bipy = 2,2′-bipyridine）, were synthesized by the hydrothermal reaction and structurally characterized. Complex 1 crystallizes in triclinic, space group P1, a = 5.581（4）, b = 12.071（8）, c = 12.88（1）A, α= 92.10（3）,β= 96.73（3）, γ = 102.02（2）°, C17H10N407Cd, Mr = 494.69, V= 841（1）A3, Z = 2, Dc = 1.954 g/cm3, F（000） = 488, μ= 1.353 mm^-1, R = 0.0248 and wR = 0.0761. Complex 2 crystallizes in monoclinic with space group P21/c, a = 8.604（3）, b = 23.88（1）, c = 8.894（3） A, β = 102.45（1）°, C17H10N407Mn, Mr = 437.23, V= 1785（1） A3, Z=.4, Dc = 1.627 g/cm3, F（000） = 884, μ = 0.791 mm^-1, R = 0.0471 and wR = 0.1250. Complex 1 possesses an infinite 1D polymeric chain structure consisting of the repeated basic four-membered ring units （Cd2O2） and eight-membered ring units （CdOCO）2. Compound 2displays a linear 1D chain through Mn（Ⅱ） atoms and bridging carboxylate groups of 3,5-dinitrosalicylic acid ligands with the Mn…Mn separation of 4.472（2）A. The fluorescence properties and cyclic voltammetric behaviors of the complexes are also reported.
基金supported by the National Natural Science Foundation of China(21272167 and 21201127)Starting-up Foundation(Q410900111 and Q410900211)+1 种基金Scientific Research Foundation of Soochow University(SDY2012A07)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Eight new ZnⅡ-yⅢ and ZnⅡ-LnⅢ heterometallic Schiff base complexes： MZnL2（NO3）3 （M = Y （1）, La （2）, Pr （3）, Nd （4）, Eu （5）, Gd （6）, Dy （7）, Er （8）; L = 2-（（（2- （imidazo[1,5-a]pyridin-3-yl）phenyl）imino）methyl）-6-methoxyphenol）, have been rationally synthesized under solvothermal conditions and characterized by IR, elemental analyses （EA）, single-crystal X-ray diffraction, and powder XRD. Furthermore, luminescence in the visible region for solids 1-8 suggested zine/ligand-centered emission at room temperature.
基金financially supported by the National Natural Science Foundation of China (Nos. 21172190, 21372192)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘An efficient method for the synthesis of some difunctionalized copillar[5]arene Schiff bases from condensation of salicylaldehyde and its 5-chloro,5-bromo,3,5-di（t-butyl） substituted derivatives with corresponding diamino-functionalized copillar[5]arene,which were prepared by Gabriel reaction according to the reported method.Single-crystals of six copillar[5]arenes were determined by X-ray diffraction.An ORTEP of compounds showed that the two chains units of Schiff base exist in the outside of the cavity of pillar[5]arene.Furthermore,the complexing ability of these Schiff bases to transition metal ions were investigated by UV and fluorescence spectroscopy.
文摘The crystal structure of the title complex salt has been determined by single-crystal X-ray structure analysis. The crystal data are as follows; Monoclinic, P21/c, a=15.6480(10)A,b=16.7870(10)A, c=10.347(2)A, β=90.790(10), V=2717.7(6)A3, Z=3, and R=0.0333 for 4789 unique reflections. The complex anion has a pseudo-octahedral structure distorted more than the CrⅢand CoⅢ analogs, in which cach iminodiacetato ligand (ida2-) is coordinated in a facial fashion with the two N atoms in a cis configuration, resulting in an unsyin-fac structure.
基金supported by the National Natural Science Foundation of China(Nos.21266019,21062011 and 21462029)Inner Mongolia Autonomous Region Higher Scientific Research Project(NJZY14060)
文摘The reactivity of carbonyl iron cluster with alkynes has been studied by the thermal reaction of Fe_3（CO）_（12） with R-C≡C-R＇（R = Fc（Ferrocenyl）; R′ = Ph（Phenyl）, Fc, H）. The hexacarbonyldiiron cluster with ferracyclopentadiene ring（μ_2, η~4-C_4Ph_4）Fe_2（CO）_6（1） and one tetraphenyl substituted cyclopentadienone（Ph_4C_4CO）（2） were simultaneously obtained by the reaction of Fe_3（CO）_（12） with alkyne（Ph-C≡C-Ph）. Only one ferrole cluster（μ_2, η~4-C_4Fc_2H_2）Fe_2（CO）_6（3） was separated by using Fc-C≡C-H as alkyne. One tri-carbonyl iron complex（η~4-C_4Fc_4CO）Fe（CO）_3（4） and an unexpected new cyclic ketone compound 2,2,4,5-tetraferrocenylcyclopenta-4-en-1,3-di-one [Fc_4C_3（CO）_2]（5） were obtained by using Fc-C≡C-Fc as alkyne. A new complex（η4-2,4-diphenyl-3,5-diferrocenylcyclopenta-2,4-dien-1-one）-tricarbonyl iron（η~4-C_4Ph_2Fc_2CO）Fe（CO）_3（6） was synthesized by the reaction of Fe_3（CO）_（12） with Fc-C≡C-Ph. The structures of compounds 1~6 were determined by X-ray single-crystal diffraction and spectroscopic characterization. The crystal structures of two new compounds 5 and 6 were analyzed. Our experimental results reveal the structural models of the reaction products are affected by the kinds of substituents from alkynes R-C≡C-R′.
基金Project supported by the National Major Science and Technology Project“Development of Large Oil/Gas Fields and Coalbed Methane”(No.2016ZX05004-005&2016ZX05007-004)the CNPC Major Science and Technology Project“Research and application of key technologies for maintaining gas productivity of 30 billion cubic meters in Southwest Oil and Gas Fields”(No.2016E-06,2016E-0602,2016E-0603&2016E-0604).
文摘The northern Sichuan Basin,spreading in the northern section of the Longmenshan Fault Fold Belt,is characterized by dramatic fluctuations in the surface landforms,development of abdominal faults,and low-quality seismic data,resulting in difficulties in clarifying relevant structures.The key target formation,the Mid-Permian Qixia Fm,is deeply buried with thin reservoirs and high heterogeneity,which brings great challenges to seismic prediction.Under such circumstances,researches have been conducted jointly in terms of seismic data acquisition,processing and interpretation,and finally some relevant seismic survey technologies were developed suitable for surface/underground complex structures.Through surface structural surveys,dynamic deep-well lithologic identification,single-point detector deployment and process optimization,acquisition parameters can be excited.In addition,by using an observation systemwith high-coverage,wide-azimuth and huge-displacement,quality of acquired seismic data can be enhanced dramatically.Seismic imaging technologies for complex structures have been developed to enhance the quality of images for deep formations.These technologies are dominated by microscopic logging-constrained tomography static correction,high-resolution processing with fidelity and amplitude preservation and all-around PSDM in an angular domain.By using high-resolution gravity,magnetic and electric data,details related to geological structures and faults can be identified.In combination with fine seismic data interpretation,structural details and fault features can be verified effectively.Based on forwardmodeling and fine seismic calibration of reservoirs in individualwells,suitable attributes can be identified for predictions related to the distribution of reservoirs.By using all these auxiliary technologies,a large-scale structuralelithologic composite trap with a total area of 1223 km^(2) has been discovered in the NW Sichuan Basin.The Shuangyushi-Jiangyou area as a whole distributes on structural highs.In the areas to the south of Shuangyushi,the Qixia Fm dolomite reservoirs of platform margins are continuously developed.In conclusion,these auxiliary technologies can effectively allow trap identification and thin reservoir prediction in complex structures in the study area.In addition to clarifying the exploration orientation and providing a necessarily technical supports forwell development,these technologies help to accelerate the construction of demonstration projects for the exploration and development of deep marine carbonate formations.
