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Pharmacodynamic Experiment of Dachengqi Decoction and Separated Decoction on Incomplete Intestinal Obstruction in Rats
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作者 Jiangcun WEI Xiumei MA +5 位作者 Bing QING Meiyan QIU Qingmei DENG Hong LEI Zengyan YANG Zujie QIN 《Medicinal Plant》 2024年第4期107-110,共4页
[Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intesti... [Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intestinal obstruction model by silk ligation.The dosage was 20 mL/kg for 3 d,and the damage index of ileocecal mucosa was analyzed;the morphology of ileocecal mucosa was observed by HE staining;the serum levels of IL-1α,IL-1β,IL-6,IL-18,Ach,NO,ET,IL-1,TNF-αand ultra-micro Na+-K+-ATPase were detected by ELISA.[Results]Compared with the model group,the mucosal damage index of Dachengqi Decoction and each separated decoction group decreased significantly(P<0.05);compared with the normal group and sham operation group,the serum level of IL-1,IL-6,TNF-αand other factors in the model group increased significantly(P<0.05);compared with the model group,the serum IL-1,IL-6 and TNF-αsecretion levels of rats in Dachengqi Decoction group and separated decoction group decreased(P<0.01).[Conclusions]Dachengqi Decoction and each separated decoction can effectively improve intestinal tissue pathological damage in the incomplete intestinal obstruction model rats,and reduce the inflammatory reaction in the rat body. 展开更多
关键词 Dachengqi Decoction separated decoction Incomplete intestinal obstruction Inflammatory factor
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Decoupled thermal–hydraulic analysis of an air-cooled separated heat pipe for spent fuel pools under natural convection 被引量:1
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作者 Hui-Lin Xue Jian-Jie Cheng +3 位作者 Wei-Hao Ji Wen-Jin Li Han-Zhong Tao Wei Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期183-197,共15页
An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal ... An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal and mass balance,this study decoupled the heat transfer processes in the SFS.In accordance with the decoupling conditions,we modeled the spent fuel pool of the CAP1400 pressurized water reactor in Weihai and used computational fluid dynamics to explore the heat dissipation capacity of the SFS under different air temperatures and wind speeds.The results show that the air-cooled separated heat pipe radiator achieved optimal performance at an air temperature of 10℃ or wind speed of 8 m/s.Fitted equations for the equivalent thermal conductivity of the separated heat pipes with the wind speed and air temperature we obtained according to the thermal resistance network model.This study is instructive for the actual operation of an SFS. 展开更多
关键词 Decoupled analysis separated heat pipe CAP1400 Finned tube radiator Passive cooling
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Development and prospect of downhole monitoring and data transmission technology for separated zone water injection 被引量:1
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作者 LIU He ZHENG Lichen +4 位作者 YU Jiaqing MING Eryang YANG Qinghai JIA Deli CAO Gang 《Petroleum Exploration and Development》 2023年第1期191-201,共11页
This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptabi... This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptability and application status of traditional downhole data acquisition method,cable communications and testing technology,cable-controlled downhole parameter real-time monitoring communication method and downhole wireless communication technology are introduced in detail.Problems and challenges of existing technologies in downhole monitoring and data transmission technology are pointed out.According to the production requirement,the future development direction of the downhole monitoring and data transmission technology for separated zone water injection is proposed.For the large number of wells adopting cable measuring and adjustment technology,the key is to realize the digitalization of downhole plug.For the key monitoring wells,cable-controlled communication technology needs to be improved,and downhole monitoring and data transmission technology based on composite coiled tubing needs to be developed to make the operation more convenient and reliable.For large-scale application in oil fields,downhole wireless communication technology should be developed to realize automation of measurement and adjustment.In line with ground mobile communication network,a digital communication network covering the control center,water distribution station and oil reservoir should be built quickly to provide technical support for the digitization of reservoir development. 展开更多
关键词 separated zone water injection downhole monitoring data transmission cable communication vibration wave pressure wave flow wave
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Deep learning enabled single-shot absolute phase recovery in high-speed composite fringe pattern profilometry of separated objects
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作者 Maciej Trusiak Malgorzata Kujawinska 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第12期1-4,共4页
A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled ... A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled fringe projection profilometry(FPP).In this News&Views article,we explore potential avenues for future advancements,including expanding the measurement range through an extended number-theoretical approach,enhancing quality through the incorporation of horizontal fringes,and integrating data from other modalities to broaden the system's applications. 展开更多
关键词 system ABSOLUTE separated
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Accurate design of spatially separated double active site in Bi_(4)NbO_(8)Cl single crystal to promote Z-Scheme photocatalytic overall water splitting
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作者 Kailong Gao Hongxia Guo +4 位作者 Yanan Hu Hongbin He Mowen Li Xiaoming Gao Feng Fu 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期568-582,I0014,共16页
The efficiency of photocatalytic overall water splitting was mainly limited by the slow reaction kinetics of water oxidation.How to design effective surface active site to overcome the slow water oxidation reaction wa... The efficiency of photocatalytic overall water splitting was mainly limited by the slow reaction kinetics of water oxidation.How to design effective surface active site to overcome the slow water oxidation reaction was a major challenge.Here,we propose a strategy to accelerate surface water oxidation through the fabrication spatially separated double active sites.FeCoPi/Bi_(4)NbO_(8)Cl-OVs photocatalyst with spatially separated double active site was prepared by hydrogen reduction photoanode deposition method.Due to the high matching of the spatial loading positions of FeCoPi and OVs with the photogenerated charge distribution of Bi_(4)NbO_(8)Cl and corresponding reaction mechanisms of substrate,the FeCoPi and OVs on the(001)and(010)crystal planes of Bi_(4)NbO_(8)Cl photocatalyst provided surface active site for water oxidation reaction and electron shuttle reaction(Fe^(3+)/Fe^(2+)),respectively.Under visible light irradiation,the evolution O_(2)rate of FeCoPi/Bi_(4)NbO_(8)Cl OVs was 16.8μmol h^(-1),as 32.9 times as Bi_(4)NbO_(8)Cl.Furthermore,a hydrogen evolution co-catalyst PtRu@Cr_(2)O_(3)was prepared by sequential photodeposition method.Due to the introduction of Ru,the Schottky barrier between PbTiO_(3)and Pt was effectively reduced,which promoted the transfer of photogenerated electrons to PtRu@Cr_(2)O_(3)thermodynamically,the evolution H_(2)rate on PtRu@Cr_(2)O_(3)/PbTiO_(3)increased to 664.8 times.On based of the synchronous enhancement of the water oxidation performance on FeCoPi/Bi_(4)NbO_(8)Cl-OVs and water reduction performance on PtRu@Cr_(2)O_(3)/PbTiO_(3),a novel Z-Scheme photocatalytic overall water splitting system(FeCoPi/Bi_(4)NbO_(8)Cl-OVs)mediated by Fe^(3+)/Fe^(2+)had successfully constructed.Under visible light irradiation,the evolution rates of H_(2)and O_(2)were 2.5 and 1.3μmol h^(-1),respectively.This work can provide some reference for the design of active site and the controllable synthesis of OVs spatial position.On the other hand,the hydrogen evolution co catalyst(PtRu@Cr_(2)O_(3))and the co catalyst FeCoPi for oxygen evolution contributed to the construction of an overall water splitting system. 展开更多
关键词 Spatially separated double active sites FeCoPi/Bi_(4)NbO_(8)Cl-OVs Photocatalytic water oxidation Photocatalytic hydrogen evolution Hydrogen evolution co-catalyst PtRu@Cr_(2)O_(3) Z-Scheme photocatalytic overall water splitting system
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Investigation of the interaction between NS-DBD plasma-induced vortexes and separated flow over a swept wing
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作者 刘备 梁华 郑博睿 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期88-99,共12页
The effect of nanosecond pulsed dielectric barrier discharge(NS-DBD) plasma flow separation control is closely related to the actuation frequency,because it involves the interaction between plasma-induced vortexes and... The effect of nanosecond pulsed dielectric barrier discharge(NS-DBD) plasma flow separation control is closely related to the actuation frequency,because it involves the interaction between plasma-induced vortexes and separated flow.In order to study the mechanism of NS-DBD plasma flow separation control over a swept wing,especially the influence of the actuation frequency,at first,experimental studies of the actuation frequencies at 100 Hz are conducted to validate the numerical simulation method.Then,numerical studies of different actuation frequencies which are 50 Hz,100 Hz,160 Hz,200 Hz,500 Hz,and 1000 Hz,respectively are conducted.The interaction between the plasma-induced vortexes and the separated flow is analyzed.Results show that there is a range of the actuation frequency which includes the frequency(160 Hz) calculated by the average aerodynamic chord length to make the control effect good,but when the actuation frequencies are too low(50 Hz) or too high(1000 Hz),the control effect will get worse.The former is because plasmainduced vortexes disappear in a period within an actuation cycle;the latter is because plasma-induced vortexes cannot develop completely,resulting in a weak vortex intensity. 展开更多
关键词 plasma-induced vortex flow separation control NS-DBD LES
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强磁场条件下的spatial separated D^-心
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作者 邢雁 王旭 《内蒙古大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第5期520-526,共7页
采用 Mac Donld的对角化法研究了强磁场条件下 D-s 心的束缚态和多电子效应 .发现D-s 心有 L=0 ,-1 ,-2 ,-3 ,-4五个束缚态 ,且随着电子与 D0 心之间距离ξ值的增大 ,其束缚能存在一极大值 .并利用无规相近似讨论了长波极限 D-s 心的多... 采用 Mac Donld的对角化法研究了强磁场条件下 D-s 心的束缚态和多电子效应 .发现D-s 心有 L=0 ,-1 ,-2 ,-3 ,-4五个束缚态 ,且随着电子与 D0 心之间距离ξ值的增大 ,其束缚能存在一极大值 .并利用无规相近似讨论了长波极限 D-s 心的多电子效应 ,发现 D-s 心的本征能量随朗道能级填充因子作周期性振荡 ,且随着温度的降低振荡加剧 ;当填充因子为偶数时 ,其本征能量的绝对值最大 ,说明此时电子气对库仑势的屏蔽效应最弱 . 展开更多
关键词 SPATIAL separated D^-心 强磁场 束缚态 多电子效应 对角化法 量子阱 哈密顿量
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SEPARATED FRAMES
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作者 张凤玲 StraussDona 《Transactions of Tianjin University》 EI CAS 1998年第1期76-79,共4页
In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the ... In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the T O space X being Hausdorff. The class of separated frames includes that of strong Hausdorff frames and that of S frames. We shall show that the class of separated frames is a class closed under the formation of coproducts and subspaces, and the space Fil( L ) is Hausdorff for any separated frame L . Therefore there is a contravariant adjunction between the category TOP 2 of Hausdorff topological spaces and the category FRAM 2 of separated frames. 展开更多
关键词 FRAME separated frame Hausdorff topological space adjunction between categories
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Comparative assessment of SAS and DES turbulence modeling for massively separated flows 被引量:3
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作者 Weilin Zheng Chao Yan +1 位作者 Hongkang Liu Dahai Luo 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第1期12-21,共10页
Numerical studies of the flow past a circular cylinder at Reynolds number 1.4 × 105 and NACA0021 airfoil at the angle of attack 60° have been carried out by scale-adaptive simulation (SAS) and detached edd... Numerical studies of the flow past a circular cylinder at Reynolds number 1.4 × 105 and NACA0021 airfoil at the angle of attack 60° have been carried out by scale-adaptive simulation (SAS) and detached eddy simu- lation (DES), in comparison with the existing experimental data. The new version of the model developed by Egorov and Menter is assessed, and advantages and disadvantages of the SAS simulation are analyzed in detail to provide guidance for industrial application in the future. Moreover, the mechanism of the scale-adaptive characteristics in separated regions is discussed, which is obscure in previous analyses. It is con- cluded that: the mean flow properties satisfactorily agree with the experimental results for the SAS simulation, although the prediction of the second order turbulent statistics in the near wake region is just reasonable. The SAS model can produce a larger magnitude of the turbulent kinetic energy in the recir- culation bubble, and, consequently, a smaller recirculation region and a more rapid recovery of the mean velocity out- side the recirculation region than the DES approach with the same grid resolution. The vortex shedding is slightly less irregular with the SAS model than with the DES approach, probably due to the higher dissipation of the SAS simulation under the condition of the coarse mesh. 展开更多
关键词 Scale-adaptivelength scale Bluff bodies SIMULATION von Karman Massively separated flows Computational fluid dynamics
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SYNTHESIS AND CHARACTERIZATION OF AMPHIPHILIC GRAFT COPOLYMER CONTAINING MICROPHASE SEPARATED AND LONG POLY(ETHYLENE OXIDE) SIDE CHAIN STRUCTURES 被引量:4
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作者 邱永兴 俞小洁 +1 位作者 封麟先 杨士林 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第1期67-75,共9页
Acryloyl terminated Poly (ethyleneoxide)macromonomers (PEO-A) with different PEO chain lengths have been prepared by deactivation of PEO alkoxide with acryloyl chloride. A new kind of amphiphilic polystyrene-g-poly (e... Acryloyl terminated Poly (ethyleneoxide)macromonomers (PEO-A) with different PEO chain lengths have been prepared by deactivation of PEO alkoxide with acryloyl chloride. A new kind of amphiphilic polystyrene-g-poly (ethylene oxide)graft copolymer containing both microphase separated and PEO side chain structures has been synthesized from radical copolymerization of PEO-A macromonomer with styrene. After careful purification by a newly-developed method called 'selective dissolution', the well-defined structure of the purified copolymers was confirmed by IR, ~1H-NMR and GPC. Various experimental parameters controlling the copolymerization were studied in detail. The results indicated that the feed ratio of styrene to macromonomer(S/M) was the most important determining factor for the composition of the copolymers. A detailed 'comb- model' was proposed to describe the molecular structure of the graft copolymers. Finally, this amphiphilic graft copolymers may readily form microphase separated structures as clearly indicated by transmission electron microscopy. 展开更多
关键词 PEO AIBN SIDE CHAIN STRUCTURES SYNTHESIS AND CHARACTERIZATION OF AMPHIPHILIC GRAFT COPOLYMER CONTAINING MICROPHASE separated AND LONG POLY ETHYLENE OXIDE PS
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Solving mKdV-sinh-Gordon equation by a modified variable separated ordinary differential equation method 被引量:4
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作者 谢元喜 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第12期5123-5132,共10页
By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact sol... By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact solutions including some new formal solutions are successfully picked up for the mKdV-sinh-Gordon equation by this approach. 展开更多
关键词 modified variable separated ODE method mKdV-sinh-Gordon equation explicit andexact solution
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Effects of Chinese Fructus Mume Formula and Its Separated Prescription Extract on Insulin Resistance in Type 2 Diabetic Rats 被引量:2
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作者 李井彬 徐丽君 +4 位作者 董慧 黄诏宜 赵炎 陈广 陆付耳 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第6期877-885,共9页
The effect of Fructus Mume formula and its separated prescription extract on insulin resis- tance in type 2 diabetic rats was investigated. The rat model of type 2 diabetes was established by feed- ing on a high-fat d... The effect of Fructus Mume formula and its separated prescription extract on insulin resis- tance in type 2 diabetic rats was investigated. The rat model of type 2 diabetes was established by feed- ing on a high-fat diet for 8 weeks and by subsequently intravenous injection of small doses of strepto- zotocin. Rats in treatment groups, including the Fructus Mume formula treatment group (FM), the cold property herbs of Fructus Mume formula treatment group (CFM), the warm property herbs of Fructus Mume formula treatment group (WFM), were administrated with Fructus Mume formula and its sepa- rated prescription extract by gavage, while the rats in diabetic model group (DM) and metformin group (MET) were given by gavage with normal saline and metformin correspondingly. The body weight be- fore and after treatment was measured, and the oral glucose tolerance test (OGTT) and the insulin re- lease test (IRT) were performed. The homeostasis model assessment-insulin resistance index (HOMA-IR) was calculated. The protein and mRNA expression levels of Insr, β-arrestin-2, Its-1 and Glut-4 in the liver, skeletal muscle and fat tissues were detected by using Western blotting and RT-PCR respectively. The results demonstrated that, as compared with DM group, OGTT, IRT (0 h, 1 h) levels and HOMR-IR in treatment groups were all reduced, meanwhile their protein and mRNA expression levels of Insr, Irs-1 and Glut-4 in the liver, skeletal muscle and fat tissues were obviously increased, and their protein and mRNA expression levels of β-arrestin-2 in the liver and skeletal muscle tissues were also markedly increased. It was suggested that the Fructus Mume formula and its separated prescription extracts could effectively improve insulin resistance in type 2 diabetic rats, which might be related to the up-regulated expression of Insr, Irs-1 and Glut-4 in the liver, skeletal muscle and fat tissues, and β-arrestin-2 in the liver and skeletal muscle tissues. 展开更多
关键词 Fructus Mume formula separated prescription type 2 diabetes insulin resistance β-arrestin-2
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Applications of URANS on predicting unsteady turbulent separated flows 被引量:2
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作者 Jinglei Xu Huiyang Ma Department of Physics, Graduate University of the Chinese Academy of Sciences, 100049 Beijing, China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第3期319-324,共6页
Accurate prediction of unsteady separated turbulent flows remains one of the toughest tasks and a practi cal challenge for turbulence modeling. In this paper, a 2D flow past a circular cylinder at Reynolds number 3,90... Accurate prediction of unsteady separated turbulent flows remains one of the toughest tasks and a practi cal challenge for turbulence modeling. In this paper, a 2D flow past a circular cylinder at Reynolds number 3,900 is numerically investigated by using the technique of unsteady RANS (URANS). Some typical linear and nonlinear eddy viscosity turbulence models (LEVM and NLEVM) and a quadratic explicit algebraic stress model (EASM) are evaluated. Numerical results have shown that a high-performance cubic NLEVM, such as CLS, are superior to the others in simulating turbulent separated flows with unsteady vortex shedding. 展开更多
关键词 URANS Nonlinear eddy viscosity turbulencemodel separated flows Circular cylinder
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A SEPARATED LAW OF HARDENING IN STRAIN GRADIENT PLASTICITY 被引量:2
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作者 张林 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1997年第2期161-164,共4页
This paper presents a separated law of hardening in plasticity with strain gradient effects. The value of the length parameter l contained in this model was estimated from the experimental data for copper.
关键词 strain gradient plasticity separated law of hardening
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OSCILLATION FREQUENCY THEORY OF A PIEZOELECTRIC SENSOR INLIQUID PHASE WITH TWO SEPARATED-ELECTRODES 被引量:1
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作者 Da Zhong SHEN Ze Chang LIU +1 位作者 Qing KANG Jind Tian HU(Chemistry College, Shandong University, Jinan, 250100)(Chemical Engineering Department, Jinan Branch of Shandong Institute of Mining and Technology, Jinan, 280031) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第2期169-172,共4页
In this paper, an oscillation frequency equation for a pizoelectric sensor with two separated-electrodes is theoretically derived and experimentally verified. The correlatione of the oscillation frequency and the liqu... In this paper, an oscillation frequency equation for a pizoelectric sensor with two separated-electrodes is theoretically derived and experimentally verified. The correlatione of the oscillation frequency and the liquid properties are investigated. 展开更多
关键词 SENSOR FREQUENCY INLIQUID OF OSCILLATION PHASE PIEZOELECTRIC ELECTRODES separated THEORY
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The research progress and prospect for the technology of controlling surface subsidence by grouting separated layer in overburden at coal mines in China 被引量:2
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作者 刘文生 范学理 《Journal of Coal Science & Engineering(China)》 2001年第1期18-24,共7页
The developed process and theoretical achievement for the technology of controlling surface subsidence by grouting separated layer in overburden is summarized in this paper. The research progress of the technology is ... The developed process and theoretical achievement for the technology of controlling surface subsidence by grouting separated layer in overburden is summarized in this paper. The research progress of the technology is discussed synthetically on the basis of practice and research results obtained at coal mine of China in recent years. According to the development tendency of mining under buildings, water bodies and railroads and the properties of the technology, the future research direction is proposed. 展开更多
关键词 strata control surface subsidence grouting separated layer in overburden
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MICROPHASE SEPARATED STRUCTURES AND PROPERTIES OF PDMS-MDIPEG COPOLYMER SURFACE 被引量:1
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作者 方红霞 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第3期327-334,共8页
A series of poly(dimethylsiloxane)(PDMS)-4,4′-diphenylmethanediisocyanate(MDI)-poly(ethylene glycol)(PEG) multiblock copolymers were synthesized by employing two-step growth polymerization and investigated by AFM,XPS... A series of poly(dimethylsiloxane)(PDMS)-4,4′-diphenylmethanediisocyanate(MDI)-poly(ethylene glycol)(PEG) multiblock copolymers were synthesized by employing two-step growth polymerization and investigated by AFM,XPS. contact angle system,protein adsorption and platelets adhesion measurements,respectively.It was found that as the molecular weight of PDMS increased,the surface of copolymers had increasing phase separation,while the increase in the molecular weight of PEG decreased the phase separation extents of the copolymer surface.XPS and contact angle measurements showed that the greater the phase separation extent was,the lower both the surface enrichment of PDMS and the surface free energy of the copolymer film were.The protein adsorption experiments indicated that the best phase separation did not exhibit the best biocompatibility. 展开更多
关键词 Microphase separated structure Multiblock copolymer PDMS-PEG-MDI Protein adsorption
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Rational design of stratified material with spatially separated catalytic sites as an efficient overall water-splitting photocatalyst 被引量:1
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作者 Yi-Lei Li Xiao-Jing Wang +4 位作者 Ying-Juan Hao Jun Zhao Ying Liu Hui-Ying Mu Fa-Tang Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第6期1040-1050,共11页
The development of metal sulfide catalysts with remarkable activity toward efficient overall photocatalytic water splitting remains challenging owing to the dominant charge recombination and deficient catalytic active... The development of metal sulfide catalysts with remarkable activity toward efficient overall photocatalytic water splitting remains challenging owing to the dominant charge recombination and deficient catalytic active sites.Moreover,in the process of water oxidation catalysis,the inhibition of severe photocorrosion is an immense task,requiring effective photogenic hole-transfer kinetics.Herein,stratified Co-MnO_(2)@CdS/CoS hollow cubes with spatially separated catalytic sites were rationally designed and fabricated as highly efficient controllable catalysts for photocatalytic overall water splitting.The unique self-templated method,including a continuous anion/cation-exchange reaction,integrates a Co-doped oxidation co-catalyst(Co-MnO_(2))and a reduction co-catalyst(CoS)on the nanocubes with uniform interface contact and ultrathin two-dimensional(2D)nanometer sheets.We demonstrate that the stratified Co-MnO_(2)@CdS/CoS hollow cubes can provide an abundance of active sites for surface redox reactions and contribute to the separation and migration of the photoionization charge carriers.In particular,CoS nanoparticles dispersed on the walls of CdS hollow cubes were identified as reduction co-catalysts accelerating hydrogen generation,while Co-MnO_(2) nanosheets attached to the inner walls of the CdS hollow cube were oxidation co-catalysts,promoting oxygen evolution dynamics.Benefiting from the desirable structural and compositional advantages,optimized stratification of Co-MnO_(2)@CdS/CoS nanocubes provided a catalytic system devoid of precious metals,which exhibited a remarkable overall photocatalytic water-splitting rate(735.4(H_(2))and 361.1(O_(2))μmol h^(−1) g^(−1)),being among the highest values reported thus far for CdS-based catalysts.Moreover,an apparent quantum efficiency(AQE)of 1.32%was achieved for hydrogen evolution at 420 nm.This study emphasizes the importance of rational design on the structure and composition of photocatalysts for overall water splitting. 展开更多
关键词 Stratified material Hollow cubes Overall water splitting Anion/cation exchange Spatially separated site
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Separated root tip formation associated with a fractured tubercle of dens evaginatus: A case report 被引量:1
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作者 Zhi-Fang Wu Ling-Jiao Lu +5 位作者 Hai-Yan Zheng Yan Tu Ying Shi Zi-Huai Zhou Lin-Xian Fang Bai-Ping Fu 《World Journal of Clinical Cases》 SCIE 2021年第12期2944-2950,共7页
BACKGROUND Several previous studies have reported an unusual root formation in which a fractured apical fragment of an immature root continued to develop independent of the main root after trauma to an immature tooth.... BACKGROUND Several previous studies have reported an unusual root formation in which a fractured apical fragment of an immature root continued to develop independent of the main root after trauma to an immature tooth.To date,there have been only rare reports of the continuing apical formation of the fractured root associated with dens evaginatus(DE).This paper presents a case of a separated root tip formation associated with a fractured tubercle of DE.CASE SUMMARY An 11-year-old boy was referred for gingival sinus on the buccal side of the right mandibular second premolar(tooth#45).Clinically,tooth#45 was free of caries,but there was a sign of a fractured tubercle of DE on the occlusal surface.Radiography showed that the root canal of tooth#45 was widely radiolucent.A separated root apex was found apically under the main root and was nearly completely formed with an apical orifice at the apical tip.Tooth#45 was diagnosed as tubular fracture of DE with chronic apical periodontitis.A revascularization technique was recommended to treat the tooth.At 3-mo and 1-yr follow-up,the patient remained asymptomatic.Periapical radiography revealed that the separated root tip distally drifted with closure of the apex.However,the root length and thickness of the main root did not increased.CONCLUSION Clinicians should be aware that even if tubercle of DE is fractured in an immature tooth,the root tip may be separated from the main root and completely formed. 展开更多
关键词 separated root tip Dens evaginatus Tubercle fracture Young permanent tooth REVASCULARIZATION Case report
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Development and prospect of separated zone oil production technology 被引量:2
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作者 LIU He ZHENG Lichen +4 位作者 YANG Qinghai YU Jiaqing YUE Qingfeng JIA Deli WANG Quanbin 《Petroleum Exploration and Development》 2020年第5期1103-1116,共14页
This article outlines the development of separated zone oil production in foreign countries,and details its development in China.According to the development process,production needs,technical characteristics and adap... This article outlines the development of separated zone oil production in foreign countries,and details its development in China.According to the development process,production needs,technical characteristics and adaptability of oilfields in China,the development of separate zone oil production technology is divided into four stages:flowing well zonal oil production,mechanical recovery and water blocking,hydraulically adjustable zonal oil production,and intelligent zonal production.The principles,construction processes,adaptability,advantages and disadvantages of the technology are introduced in detail.Based on the actual production situation of the oilfields in China at present,three development directions of the technology are proposed.First,the real-time monitoring and adjustment level of separated zone oil production needs to be improved by developing downhole sensor technology and two-way communication technology between ground and downhole and enhancing full life cycle service capability and adaptability to horizontal wells.Second,an integrated platform of zonal oil production and management should be built using a digital artificial lifting system.Third,integration of injection and production should be implemented through large-scale application of zonal oil production and zonal water injection to improve matching and adjustment level between the injection and production parameters,thus making the development adjustment from"lag control"to"real-time optimization"and improving the development effect. 展开更多
关键词 separated zone oil production flowing well zonal oil production mechanical recovery and water plugging hydraulically adjustable zonal oil production intelligent zonal oil production PROSPECT
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