Nine compounds were isolated from Elsholtzia blanda (Benth.) Benth. Their structures were identified with spectral and chemical methods as follows: 5,6-dihydro-6-styry-2-pyrone (1), friedelin (2), 4-hydroxy-3-methoxys...Nine compounds were isolated from Elsholtzia blanda (Benth.) Benth. Their structures were identified with spectral and chemical methods as follows: 5,6-dihydro-6-styry-2-pyrone (1), friedelin (2), 4-hydroxy-3-methoxystyrene (3), 5,2'-dimethoxy-6, 7-methylene dioxyflavanone (4), 5-hydroxy-7-methoxy-6-O-[alpha -L-rhamnopyranosyl(1 -->2) -beta -D-fucopyranosyl] flavone glycoside (5), 5, 5'-dihydroxy-7-acetoxyl-6, 8, 3',3'-tetramethylpyran (3',4') navone (6), 5, 5'-dihydroxy-7-(alpha -methyl) butyroxyl-6, 8, 3 ', 3'-tetramethylpyran (3',4') flavone (7), 5,5'-dihydroxy-6, 7-methylenedioxy-8, 3', 3'-trimethylpyran (3',4') navone (8), glucosyringic acid (9). Among them, 6, 7 and 8 are new compounds, named as sifanghaoine I,II and III, respectively.展开更多
The experiments and numerical simulation were conducted for ZL205A aluminum alloy cylindrical shell casting. The formation mechanism of the linear segregation produced by the low pressure die casting (LPDC) process wa...The experiments and numerical simulation were conducted for ZL205A aluminum alloy cylindrical shell casting. The formation mechanism of the linear segregation produced by the low pressure die casting (LPDC) process was investigated. And the heat transfer of the casting during solidification process was analyzed by simulation technique, resulting from the information of linear segregation obtained by plenty of experiments. The new linear segregation criterion was proposed through the simulation and experimental results. It was found that the melting metal with high Cu contents was feeding the crack shrinkage formed by the tearing under the effect of feeding pressure during the later solidification, which led to the formation of linear segregation. The control methods for the linear segregation were suggested based on the proposed mechanism. Finally, the criterion of linear segregation was confirmed by the production of the actual castings.展开更多
The mechanism of antithrombotic of Dahuangzhechong Fang separated and purified by Ti-Al intermetallic compound porous material (TAICPM) was researched. Dahuangzhechong Fang, which was isolated and screened by TAICPM, ...The mechanism of antithrombotic of Dahuangzhechong Fang separated and purified by Ti-Al intermetallic compound porous material (TAICPM) was researched. Dahuangzhechong Fang, which was isolated and screened by TAICPM, was used to oral rats. At the end of study, their blood and thrombus were collected. The results show that TAICPM with the pore size of 1-5 μm can screen Dahuangzhechong Fang well. Dahuangzhechong Fang can increase 6-keto-PGF1α, lower content of TXD2 and platelet. Dahuangzhechong Fang has good effect to resist arterial thrombosis.展开更多
How to extract optimal composite attributes from a variety of conventional seismic attributes to detect reservoir features is a reservoir predication key,which is usually solved by reducing dimensionality.Principle co...How to extract optimal composite attributes from a variety of conventional seismic attributes to detect reservoir features is a reservoir predication key,which is usually solved by reducing dimensionality.Principle component analysis（PCA） is the most widely-used linear dimensionality reduction method at present.However,the relationships between seismic attributes and reservoir features are non-linear,so seismic attribute dimensionality reduction based on linear transforms can＇t solve non-linear problems well,reducing reservoir prediction precision.As a new non-linear learning method,manifold learning supplies a new method for seismic attribute analysis.It can discover the intrinsic features and rules hidden in the data by computing low-dimensional,neighborhood-preserving embeddings of high-dimensional inputs.In this paper,we try to extract seismic attributes using locally linear embedding（LLE）,realizing inter-horizon attributes dimensionality reduction of 3D seismic data first and discuss the optimization of its key parameters.Combining model analysis and case studies,we compare the dimensionality reduction and clustering effects of LLE and PCA,both of which indicate that LLE can retain the intrinsic structure of the inputs.The composite attributes and clustering results based on LLE better characterize the distribution of sedimentary facies,reservoir,and even reservoir fluids.展开更多
Flat metal strips are deformed progressively into profiles with certain geometry sections by a series of successive rotating rolls at the room temperature, and it is called the cold roll-forming. An effective method i...Flat metal strips are deformed progressively into profiles with certain geometry sections by a series of successive rotating rolls at the room temperature, and it is called the cold roll-forming. An effective method is given for roll design to avoid major defects via finite element method （FEM） simulation using a booting model. The simulation gives reasonable fit to the actual product in the two major roll-forming defects, i.e. , edge wave and springback. The redesigned rolls using the approach of multi-stand FEM simulation can effectively control these two defects.展开更多
文摘The experiments and numerical simulation were conducted for ZL205A aluminum alloy cylindrical shell casting. The formation mechanism of the linear segregation produced by the low pressure die casting (LPDC) process was investigated. And the heat transfer of the casting during solidification process was analyzed by simulation technique, resulting from the information of linear segregation obtained by plenty of experiments. The new linear segregation criterion was proposed through the simulation and experimental results. It was found that the melting metal with high Cu contents was feeding the crack shrinkage formed by the tearing under the effect of feeding pressure during the later solidification, which led to the formation of linear segregation. The control methods for the linear segregation were suggested based on the proposed mechanism. Finally, the criterion of linear segregation was confirmed by the production of the actual castings.
基金Project (2010FA32370) supported by The Ministry of Science and Technology of ChinaProject (2008WK3002) supported by Hunan Provincial Science and Technology DepartmentProject (20060390891) supported by the Postdoctoral Science Foundation of China
文摘The mechanism of antithrombotic of Dahuangzhechong Fang separated and purified by Ti-Al intermetallic compound porous material (TAICPM) was researched. Dahuangzhechong Fang, which was isolated and screened by TAICPM, was used to oral rats. At the end of study, their blood and thrombus were collected. The results show that TAICPM with the pore size of 1-5 μm can screen Dahuangzhechong Fang well. Dahuangzhechong Fang can increase 6-keto-PGF1α, lower content of TXD2 and platelet. Dahuangzhechong Fang has good effect to resist arterial thrombosis.
基金National Key Science & Technology Special Projects(Grant No.2008ZX05000-004)CNPC Projects(Grant No.2008E-0610-10).
文摘How to extract optimal composite attributes from a variety of conventional seismic attributes to detect reservoir features is a reservoir predication key,which is usually solved by reducing dimensionality.Principle component analysis（PCA） is the most widely-used linear dimensionality reduction method at present.However,the relationships between seismic attributes and reservoir features are non-linear,so seismic attribute dimensionality reduction based on linear transforms can＇t solve non-linear problems well,reducing reservoir prediction precision.As a new non-linear learning method,manifold learning supplies a new method for seismic attribute analysis.It can discover the intrinsic features and rules hidden in the data by computing low-dimensional,neighborhood-preserving embeddings of high-dimensional inputs.In this paper,we try to extract seismic attributes using locally linear embedding（LLE）,realizing inter-horizon attributes dimensionality reduction of 3D seismic data first and discuss the optimization of its key parameters.Combining model analysis and case studies,we compare the dimensionality reduction and clustering effects of LLE and PCA,both of which indicate that LLE can retain the intrinsic structure of the inputs.The composite attributes and clustering results based on LLE better characterize the distribution of sedimentary facies,reservoir,and even reservoir fluids.
文摘Flat metal strips are deformed progressively into profiles with certain geometry sections by a series of successive rotating rolls at the room temperature, and it is called the cold roll-forming. An effective method is given for roll design to avoid major defects via finite element method （FEM） simulation using a booting model. The simulation gives reasonable fit to the actual product in the two major roll-forming defects, i.e. , edge wave and springback. The redesigned rolls using the approach of multi-stand FEM simulation can effectively control these two defects.
