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Parameters of new three-water model based on nuclear magnetic experiment and optimization algorithm
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作者 KANG Nan HONG Xin +3 位作者 ZHANG Lihua PAN Baozhi TANG Lei ZHANG Pengji 《Global Geology》 2023年第1期57-62,共6页
Clastic rock reservoir is the main reservoir type in the oil and gas field.Archie formula or various conductive models developed on the basis of Archie’s formula are usually used to interpret this kind of reservoir,a... Clastic rock reservoir is the main reservoir type in the oil and gas field.Archie formula or various conductive models developed on the basis of Archie’s formula are usually used to interpret this kind of reservoir,and the three-water model is widely used as well.However,there are many parameters in the threewater model,and some of them are difficult to determine.Most of the determination methods are based on the statistics of large amount of experimental data.In this study,the authors determine the value of the parameters of the new three-water model based on the nuclear magnetic data and the genetic optimization algorithm.The relative error between the resistivity calculated based on these parameters and the resistivity measured experimentally at 100%water content is 0.9024.The method studied in this paper can be easily applied without much experimental data.It can provide reference for other regions to determine the parameters of the new three-water model. 展开更多
关键词 new three-water model optimization algorithm NMR water saturation rock electric parameters
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Endoscopic diagnosis and management of gallbladder carcinoma in minimally invasive era:New needs,new models
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作者 La-Cuo Deqing Jun-Wen Zhang Jian Yang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第11期4333-4337,共5页
Gallbladder cancer(GBC)is a rare and lethal malignancy;however,it represents the most common type of biliary tract cancer.Patients with GBC are often diagnosed at an advanced stage,thus,unfortunately,losing the opport... Gallbladder cancer(GBC)is a rare and lethal malignancy;however,it represents the most common type of biliary tract cancer.Patients with GBC are often diagnosed at an advanced stage,thus,unfortunately,losing the opportunity for curative surgical intervention.This situation leads to lower quality of life and higher mortality rates.In recent years,the rapid development of endoscopic equipment and techniques has provided new avenues and possibilities for the early and minimally invasive diagnosis and treatment of GBC.This editorial comments on the article by Pavlidis et al.Building upon their work,we explore the new needs and corresponding models for managing GBC from the endoscopic diagnosis and treatment perspective. 展开更多
关键词 ENDOSCOPY Diagnosis and treatment Gallbladder carcinoma Minimal invasive new need new model
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Construction of the underlying circRNA-miRNA-mRNA regulatory network and a new diagnostic model in ulcerative colitis by bioinformatics analysis
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作者 Yu-Yi Yuan Hui Wu +2 位作者 Qian-Yun Chen Heng Fan Bo Shuai 《World Journal of Clinical Cases》 SCIE 2024年第9期1606-1621,共16页
BACKGROUND Circular RNAs(circRNAs)are involved in the pathogenesis of many diseases through competing endogenous RNA(ceRNA)regulatory mechanisms.AIM To investigate a circRNA-related ceRNA regulatory network and a new ... BACKGROUND Circular RNAs(circRNAs)are involved in the pathogenesis of many diseases through competing endogenous RNA(ceRNA)regulatory mechanisms.AIM To investigate a circRNA-related ceRNA regulatory network and a new predictive model by circRNA to understand the diagnostic mechanism of circRNAs in ulcerative colitis(UC).METHODS We obtained gene expression profiles of circRNAs,miRNAs,and mRNAs in UC from the Gene Expression Omnibus dataset.The circRNA-miRNA-mRNA network was constructed based on circRNA-miRNA and miRNA-mRNA interactions.Functional enrichment analysis was performed to identify the biological mechanisms involved in circRNAs.We identified the most relevant differential circRNAs for diagnosing UC and constructed a new predictive nomogram,whose efficacy was tested with the C-index,receiver operating characteristic curve(ROC),and decision curve analysis(DCA).RESULTS A circRNA-miRNA-mRNA regulatory network was obtained,containing 12 circRNAs,three miRNAs,and 38 mRNAs.Two optimal prognostic-related differentially expressed circRNAs,hsa_circ_0085323 and hsa_circ_0036906,were included to construct a predictive nomogram.The model showed good discrimination,with a C-index of 1(>0.9,high accuracy).ROC and DCA suggested that the nomogram had a beneficial diagnostic ability.CONCLUSION This novel predictive nomogram incorporating hsa_circ_0085323 and hsa_circ_0036906 can be conveniently used to predict the risk of UC.The circRNa-miRNA-mRNA network in UC could be more clinically significant. 展开更多
关键词 Circular RNAs RNA regulatory network Ulcerative colitis new predictive model BIOINFORMATICS DIAGNOSE
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Electromechanical Transient Modeling Analysis of Large-Scale New Energy Grid Connection
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作者 Shichao Cao Yonggang Dong Xiaoying Liu 《Energy Engineering》 EI 2024年第4期1109-1125,共17页
The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance a... The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance as the generator.It is the key technology to realize new energy grid connections’stable and reliable operation.This project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor.A new energy storage method is proposed.The mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power,state of charge,operation efficiency,dead zone,and inverter constraint.The rapid conversion of energy storage devices absorbs the excess instantaneous kinetic energy caused by interference.The branch transient of the critical cut set in the system can be confined to a limited area.Thus,the virtual synchronizer’s kinetic and potential energy can be efficiently converted into an instantaneous state.The simulation of power system analysis software package(PSASP)verifies the correctness of the theory and algorithm in this paper.This paper provides a theoretical basis for improving the transient stability of new energy-connected power grids. 展开更多
关键词 new energy grid connection transient electromechanical modeling synchronous virtual machine PSASP software energy storage
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Study on the Construction and Evaluation System of Clinical Midwifery Teaching Faculty under the New Nursing Model
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作者 Ying Zhou Xiwei Zhang +2 位作者 Lijun Song Yingying Xiao Hua Zhang 《Journal of Clinical and Nursing Research》 2024年第7期35-41,共7页
Objective:To explore the impact of the construction of a clinical midwifery teaching faculty and the development of an evaluation system under the new nursing model on the current teaching quality.Methods:From July 20... Objective:To explore the impact of the construction of a clinical midwifery teaching faculty and the development of an evaluation system under the new nursing model on the current teaching quality.Methods:From July 2022 to March 2023,10 clinical teaching teachers and 20 midwifery interns from Beijing Anzhen Hospital affiliated with Capital Medical University were selected as the subjects of this study.The clinical teaching teachers and midwifery interns were divided into an observation group and a control group,with each group including 5 clinical teaching teachers and 10 midwifery interns.The observation group received daily management and evaluation under the new nursing model,while the control group received management and evaluation under the traditional nursing model.The teaching quality evaluation of clinical midwifery teaching teachers by midwifery interns,the exit exam scores of midwifery interns,and the scores of clinical teaching teachers’internship lectures and teaching rounds were compared between the two groups.Results:In the observation group,the scores for teaching attitude,teaching skills,and teaching management in the teaching quality evaluation of clinical midwifery teaching teachers were higher than those in the control group.The professional theory scores(91.28±3.64)and overall nursing comprehensive scores(92.56±4.38)of midwifery interns in the observation group were higher than those of midwifery interns in the control group(81.58±2.27 and 80.29±3.33,respectively).The scores for internship lectures(89.32±4.15)and teaching rounds(90.64±5.52)in the observation group were also significantly higher than those in the control group(80.46±3.28 and 81.24±4.38,respectively),and the differences were statistically significant(P<0.05).Conclusion:The management of the clinical midwifery teaching faculty under the new nursing model effectively improved the quality of clinical teaching.It significantly enhanced the teaching effectiveness of clinical teaching teachers and the proficiency of midwifery interns in clinical operations,making it worthy of promotion and use. 展开更多
关键词 Clinical teaching Teaching faculty new nursing model Evaluation system
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Economic Analysis and Research of New Energy Vehicle Promotion Model
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作者 Zihang Wang Xudong Wang +2 位作者 Zhenyin Zhang Shaolong Wang Chenyang Xu 《Proceedings of Business and Economic Studies》 2024年第1期169-179,共11页
New energy vehicles represent the inevitable trend of future development.Compared to traditional fuel vehicles,they are more energy-saving and environmentally friendly,effectively reducing air pollution and mitigating... New energy vehicles represent the inevitable trend of future development.Compared to traditional fuel vehicles,they are more energy-saving and environmentally friendly,effectively reducing air pollution and mitigating excessive exploitation of oil resources,a stance strongly supported by governments.However,new energy vehicles possess certain drawbacks in terms of price and usability compared to traditional counterparts.Therefore,external support is imperative for their development.This paper delineates four main sections:the background of new energy vehicle promotion and application,a comparative analysis of domestic and foreign promotion models,specific promotion suggestions,and future development prospects.By leveraging insights from economic analysis,the optimal promotion model for new energy vehicles is elucidated. 展开更多
关键词 new energy vehicle engineering Promotion model Economic analysis Sustainable development
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Structure of the Quarks and a New Model of Protons and Neutrons: Answer to Some Open Questions
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作者 Ágnes Cziráki 《Natural Science》 CAS 2023年第1期11-18,共8页
The described structural model tries to answer some open questions such as: Why do quarks not exist in the open state? Where are the antiparticles from the Big Bang?
关键词 Structure of Quarks new model PROTON Neutron Open Questions
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Simulation Analysis of New Energy Vehicle Engine Cooling System Based on K-E Turbulent Flow Mathematical Model
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作者 Hongyu Mu Yinyan Wang +7 位作者 Chuanlei Yang Hong Teng Xingtian Zhao Hongquan Lu Dechun Wang Shiyang Hao Xiaolong Zhang Yan Jin 《Energy Engineering》 EI 2023年第10期2325-2342,共18页
New energy vehicles have better clean and environmental protection characteristics than traditional fuel vehicles.The new energy engine cooling technology is critical in the design of new energy vehicles.This paper us... New energy vehicles have better clean and environmental protection characteristics than traditional fuel vehicles.The new energy engine cooling technology is critical in the design of new energy vehicles.This paper used oneand three-way joint simulation methods to simulate the refrigeration system of new energy vehicles.Firstly,a k-εturbulent flow model for the cooling pump flow field is established based on the principle of computational fluid dynamics.Then,the CFD commercial fluid analysis software FLUENT is used to simulate the flow field of the cooling pump under different inlet flow conditions.This paper proposes an optimization scheme for new energy vehicle engines’“boiling”phenomenon under high temperatures and long-time climbing conditions.The simulation results show that changing the radiator’s structure and adjusting the thermostat’s parameters can solve the problem of a“boiling pot.”The optimized new energy vehicle engine can maintain a better operating temperature range.The algorithm model can reference each cryogenic system component hardware selection and control strategy in the new energy vehicle’s engine. 展开更多
关键词 new energy vehicle new energy vehicle engine k-ε turbulent flow mathematical model cooling system PID control
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A New Model of Software Engineering Education and Exploration of Professional Curriculum Teaching
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作者 Qingzhen Xu Mingzhi Mao Niansheng Cheng 《计算机教育》 2023年第12期150-157,共8页
This paper focuses on the problems,opportunities,and challenges faced by software engineering education in the new era.We have studied the core ideas of the new model and reform,the specific measures implemented,and t... This paper focuses on the problems,opportunities,and challenges faced by software engineering education in the new era.We have studied the core ideas of the new model and reform,the specific measures implemented,and the challenges and solutions faced.The new model and reform must focus on cultivating practical abilities,introducing interdisciplinary knowledge,and strengthening innovation awareness and entrepreneurial spirit.The process of reform and innovation is carried out from the aspects of teaching methods,teaching means,and course performance evaluation in the teaching practice of software engineering courses.We adopt a method of“question guiding,simple and easy to understand,flexible and diverse,and emphasizing practical results”,optimizing the curriculum design,providing diverse learning opportunities,and establishing a platform for the industry-university-research cooperation.Our teaching philosophy is to adhere to the viewpoint of innovative teaching ideas,optimizing teaching methods and teaching means,and comprehensively improving the teaching quality and level of software engineering education. 展开更多
关键词 Software engineering education new model Professional course teaching
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A new mixed-mode phase-field model for crack propagation of brittle rock
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作者 Qiuhua Rao Chenchen Zhao Wei Yi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第5期1186-1199,共14页
Study on crack propagation process of brittle rock is of most significance for cracking-arrest design and cracking-network optimization in rock engineering.Phase-field model(PFM)has advantages of simplicity and high c... Study on crack propagation process of brittle rock is of most significance for cracking-arrest design and cracking-network optimization in rock engineering.Phase-field model(PFM)has advantages of simplicity and high convergence over the common numerical methods(e.g.finite element method,discrete element method,and particle manifold method)in dealing with three-dimensional and multicrack problems.However,current PFMs are mainly used to simulate mode-I(tensile)crack propagation but difficult to effectively simulate mode-II(shear)crack propagation.In this paper,a new mixed-mode PFM is established to simulate both mode-I and mode-II crack propagation of brittle rock by distinguishing the volumetric elastic strain energy and deviatoric elastic strain energy in the total elastic strain energy and considering the effect of compressive stress on mode-II crack propagation.Numerical solution method of the new mixed-mode PFM is proposed based on the staggered solution method with self-programmed subroutines UMAT and HETVAL of ABAQUS software.Three examples calculated using different PFMs as well as test results are presented for comparison.The results show that compared with the conventional PFM(which only simulates the tensile wing crack but not mode-II crack propagation)and the modified mixed-mode PFM(which has difficulty in simulating the shear anti-wing crack),the new mixed-mode PFM can successfully simulate the whole trajectories of mixed-mode crack propagation(including the tensile wing crack,shear secondary crack,and shear anti-wing crack)and mode-II crack propagation,which are close to the test results.It can be further extended to simulate multicrack propagation of anisotropic rock under multi-field coupling loads. 展开更多
关键词 new mixed-mode phase-field model(PFM) Mode-I and mode-II crack propagation Volumetric strain energy Deviatoric elastic strain energy Compressive stress Brittle rock
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Numerical analysis of high‑speed railway slab tracks using calibrated and validated 3D time‑domain modelling
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作者 A.F.Esen O.Laghrouche +4 位作者 P.K.Woodward D.Medina‑Pineda Q.Corbisez J.Y.Shih D.P.Connolly 《Railway Engineering Science》 EI 2024年第1期36-58,共23页
Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance frequency.In this paper,the elastic performance of a ... Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance frequency.In this paper,the elastic performance of a novel slab trackform for high-speed railways is investigated using three-dimensional finite element modelling in Abaqus.It is then compared to the performance of a ballasted track.First,slab and ballasted track models are developed to replicate the full-scale testing of track sections.Once the models are calibrated with the experimental results,the novel slab model is developed and compared against the calibrated slab track results.The slab and ballasted track models are then extended to create linear dynamic models,considering the track geodynamics,and simulating train passages at various speeds,for which the Ledsgard documented case was used to validate the models.Trains travelling at low and high speeds are analysed to investigate the track deflections and the wave propagation in the soil,considering the issues associated with critical speeds.Various train loading methods are discussed,and the most practical approach is retained and described.Moreover,correlations are made between the geotechnical parameters of modern high-speed rail and conventional standards.It is found that considering the same ground condition,the slab track deflections are considerably smaller than those of the ballasted track at high speeds,while they show similar behaviour at low speeds. 展开更多
关键词 High-speed railways Slab track new ballastless track Ballasted track Critical speeds Finite element modelling Calibration of numerical models
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Exploration on New Campus Courier Service Models
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作者 傅钰 齐天真 《Agricultural Science & Technology》 CAS 2016年第5期1271-1273,共3页
Recently,e-commerce develops rapidly,advancing express delivery services,but the whole logistics are incomplete,especially for the issue of "the last one-kilometer ".For example,the research reviewed status quo and ... Recently,e-commerce develops rapidly,advancing express delivery services,but the whole logistics are incomplete,especially for the issue of "the last one-kilometer ".For example,the research reviewed status quo and problems of Tianjin Agricultural University and made improvements on campus delivery services to explore the status quo and resolving ways,exploit the hint business opportunity in campus express model,improve efficiency and service attitude and get doublewin of both parties involved. 展开更多
关键词 Campus courier service The last one-kilometer new model
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A Brief Analysis of the New Translation-comparison Model——from the View of Assimilation and Accommodation
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作者 佘阿莉 《教师》 2017年第35期48-49,共2页
关键词 new translation-comparison model ASSIMILATION ACCOMMODATION
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New lumped-mass-stick model based on modal characteristics of structures: development and application to a nuclear containment building 被引量:8
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作者 Hwasung Roh Huseok Lee Jong Seh Lee 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第2期307-317,共11页
In this study, a new lumped-mass-stick model (LMSM) is developed based on the modal characteristics of a structure such as eigenvalues and eigenvectors. The simplified model, named the "frequency adaptive lumped-ma... In this study, a new lumped-mass-stick model (LMSM) is developed based on the modal characteristics of a structure such as eigenvalues and eigenvectors. The simplified model, named the "frequency adaptive lumped-massstick model," hasonly a small number of stick elements and nodes to provide the same natural frequencies of the structure and is applied to a nuclear containment building. To investigate the numerical performance of the LMSM, a time history analysis is carried out on both the LMSM and the finite element model (FEM) for a nuclear containment building. A comparison of the results shows that the dynamic responses of the LMSM in terms of displacement and acceleration are almost identical to those of the FEM. In addition, the results in terms of floor response spectra at certain elevations are also in good agreement. 展开更多
关键词 new lumped-mass-stick model frequency adaptive nuclear containment buildings seismic response floor response spectrum
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Sodium iodate induced retinal degeneration: new insights from an old model 被引量:8
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作者 Ram Kannan David R.Hinton 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第23期2044-2045,共2页
Studies on the selective retinal degeneration induced by sodium iodate (NaIO3) date back to 1941; Sorsby (1941) described the effect of intravenously injected NaIO3 solution on the rabbit retina. Since then, NaIO3... Studies on the selective retinal degeneration induced by sodium iodate (NaIO3) date back to 1941; Sorsby (1941) described the effect of intravenously injected NaIO3 solution on the rabbit retina. Since then, NaIO3-induced retinal degeneration has been described in different mammalian species including sheep, rabbit, rat and mouse with varying doses and routes of administration. At the present time, 展开更多
关键词 IO new insights from an old model RPE
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A new expansion method of first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term and its application to mBBM model 被引量:3
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作者 潘军廷 龚伦训 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期399-402,共4页
Based on a first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term which is extended from a type of elliptic equation, and by converting it into a new expansion form, this paper... Based on a first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term which is extended from a type of elliptic equation, and by converting it into a new expansion form, this paper proposes a new algebraic method to construct exact solutions for nonlinear evolution equations. Being concise and straightforward, the method is applied to modified Benjamin-Bona-Mahony (mBBM) model, and some new exact solutions to the system are obtained. The algorithm is of important significance in exploring exact solutions for other nonlinear evolution equations. 展开更多
关键词 nonlinear evolution equations new expansion method mBBM model exact solutions
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New Method of Total Ionizing Dose Compact Modeling in Partially Depleted Silicon-on-Insulator MOSFETs 被引量:4
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作者 黄建强 何伟伟 +3 位作者 陈静 罗杰馨 吕凯 柴展 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第9期82-85,共4页
On the basis of a detailed discussion of the development of total ionizing dose (TID) effect model, a new commercial-model-independent TID modeling approach for partially depleted silicon-on-insulator metal-oxide- s... On the basis of a detailed discussion of the development of total ionizing dose (TID) effect model, a new commercial-model-independent TID modeling approach for partially depleted silicon-on-insulator metal-oxide- semiconductor field effect transistors is developed. An exponential approximation is proposed to simplify the trap charge calculation. Irradiation experiments with 60Co gamma rays for IO and core devices are performed to validate the simulation results. An excellent agreement of measurement with the simulation results is observed. 展开更多
关键词 of new Method of Total Ionizing Dose Compact modeling in Partially Depleted Silicon-on-Insulator MOSFETs for SOI TID in is IO NMOS on
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A New Example of Retrograde Solubility Model for Carbonate Rocks 被引量:2
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作者 LIU Lihong WANG Chunlian +1 位作者 WANG Daming WANG Haida 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期1145-1146,共2页
Objective The dissolution and precipitation of carbonate during burial diagenetic process controls the reservoir property in deep buried strata. The geological process related with it has become a research focus durin... Objective The dissolution and precipitation of carbonate during burial diagenetic process controls the reservoir property in deep buried strata. The geological process related with it has become a research focus during recent years. The most important dissolution fluids to carbonates are probably H2S and CO2 as byproducts of sulfate reduction in deep-buried setting with sulfate minerals, but carbonates are more soluble in relatively low temperature, which is the so-called retrograde solubility. Several geological processes can result in the decrease of temperature, including the upward migration of thermal fluids and tectonic uplift. 展开更多
关键词 of on with WELL A new Example of Retrograde Solubility model for Carbonate Rocks for
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THE EXACT ANALYTICAL SOLUTIONS TO THE NEW MODEL OF RESERVOIR FILTRATION PROBLEM 被引量:1
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作者 李笑萍 赵子刚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第7期615-626,共12页
The present study has obtained the new model of the reservoir filtration problem by taking into account the effect of wellbore storage and skin and by making use of the coupled equations of doubled porous media filtra... The present study has obtained the new model of the reservoir filtration problem by taking into account the effect of wellbore storage and skin and by making use of the coupled equations of doubled porous media filtration and consequently has got, through various forms of limits, the exact analytical solutions of the three common reservoirs (fissure, homogeneous and the two-layered) pressure distribution under the conditions of three boundaries, i.e., infinite boundary, sealed finite boundary and the finite boundary at constant pressures. 展开更多
关键词 reservoir filtration new model exact analytical solutions
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Selection of New Countryside Construction Model and Enlightenment for Ganlu Town, Zizhong County, Neijiang City 被引量:1
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作者 JING Zhihui JIAN Xiaoling 《Journal of Landscape Research》 2013年第5期8-10,共3页
Basic conditions and new countryside construction of Ganlu Town, Zizhong County, Neijiang City were analyzed, SWOT adopted to analyze internal strengths, weaknesses, external opportunities and threats of its new count... Basic conditions and new countryside construction of Ganlu Town, Zizhong County, Neijiang City were analyzed, SWOT adopted to analyze internal strengths, weaknesses, external opportunities and threats of its new countryside construction. On this basis, positive and practical strategies were put forward to promote the new countryside construction in the local area, and provide references for the new countryside construction in other regions. 展开更多
关键词 new COUNTRYSIDE construction model Ganlu TOWN SWOT Strategy
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