Traditional fluid production profile logging is not usually suitable for heavy-viscous crude oil wells.Biodegradation of heavy oil can lead to the loss of n-alkanes,and the use of chromatogram fingerprint techniques i...Traditional fluid production profile logging is not usually suitable for heavy-viscous crude oil wells.Biodegradation of heavy oil can lead to the loss of n-alkanes,and the use of chromatogram fingerprint techniques in studying the production contributions of single layers in heavy oil commingled wells has limitations.However,aromatic compounds are relatively well preserved.We took the heavy oil commingled wells of small layers NG55 and NG61 in the ninth area of the Gudong oil field as examples.Based on the principle of chromatography,the whole-oil GC-MS was used,and the aromatic parameters which have a strongly linear relationship with the ratio of mixed two end member oils were verified and selected in laboratory.Studies showed that the ratio of (1,4,6-+ 2,3,6-trimethylnaphthalene) to 1,2,5-trimethylnaphthalene has a strongly linear relationship with the ratio of the mixed two end member oils (R2=0.992).The oil contributions from single layers NG55 and NG61 in six commingled heavy oil wells were calculated using established charts and this relationship.The calculated results are consistent with the results of long period dynamic monitoring and logging interpretation in the study area and can provide a scientific basis for monitoring production performance and hierarchical management of reservoirs.The study provides a new geochemical method for calculation of the contributions of single layers in heavy oil commingled wells when conventional fluid production profile logging is not suitable.展开更多
For high corrosion resistance and extensively modified biodegradable Mg-based alloys and composites for bone implants,a new Mgbased matrix model prepared by powder metallurgy is discussed and developed.In this researc...For high corrosion resistance and extensively modified biodegradable Mg-based alloys and composites for bone implants,a new Mgbased matrix model prepared by powder metallurgy is discussed and developed.In this research,Mg-5 wt.%Zn alloys were selected as a case.And they were impacted by hot extrusion and aging treatments to construct microstructure with different characteristics.Their selfforming corrosion product layer in Ringer’s solution,biodegradable behavior and corrosion mechanism were minutely investigated by in vitro degradation,electrochemical corrosion and cytocompatibility.The results demonstrated the extruded Mg-5 wt.%Zn alloy aged for 96 h showed high corrosion resistance,good biocompatibility for L929 and excellent ability of maintaining sample integrity during the immersion.Significantly,the alloy showed fine-grain microstructure and uniform distributed hundred nano-sized second phases,which promoted the formation of the uniform and smooth corrosion product layer at the beginning of immersion.The corrosion product layer was more stable in chloride containing aqueous solution and could be directly formed and repaired quickly,which effectively protected the matrix from further corrosion.In addition,an ideal model of Mg-based matrix for bone tissue engineering was tried to presume and propose by discussing the causal relationship between microstructure and bio-corrosion process.展开更多
Packaging is one of the most important methods of keeping the quality of food products for storage, transportation and end-use. The price of materials employed for packaging food has traditionally been high and used t...Packaging is one of the most important methods of keeping the quality of food products for storage, transportation and end-use. The price of materials employed for packaging food has traditionally been high and used to be more expensive than the food itself. Technological innovations made possible to produce packaging materials cheaply. One of these processes is known as co-extrusion. This technique makes a film with two or more layers with different plastics not laminating the layers together with an adhesive, eliminating the use of solvents and producing a film in just one step instead multiple steps. In this background, our paper relates to the evolution on packaging for foods by using patenting documents. A search for patent documents was performed on free patent databases using keywords and International Patent Classification (IPC) codes related to this technology. As results: (a) 17% of the 21,472 documents found are focused on multilayer packaging for food; (b) 12 countries hold more than 90% of patents (38% Japan; 23% The United States of America; 7% Canada and 6% Germany); and, (c) two peaks were perceived in the period of 1992-1994 and 2003, and matches, respectively, the Persian Gulf (1990-1991) and Iraq Wars (2003-invasion of Iraq), so the historical tendency is confirmed: "wars also generate scientific and technological innovations".展开更多
Taking the Gaoshangpu-Liuzan geothermal field in the Nanpu sag of the Bohai Bay Basin as the research object, this paper discusses the geological conditions and potential of the geothermal resources of the Guantao For...Taking the Gaoshangpu-Liuzan geothermal field in the Nanpu sag of the Bohai Bay Basin as the research object, this paper discusses the geological conditions and potential of the geothermal resources of the Guantao Formation in the study area, and introduces the development practice of geothermal energy heating in Caofeidian. The average buried depth of the Guantao Formation is 1500–2500 m, the lithology is dominated by sandy conglomerate, and the average thickness of thermal reservoir is 120–300 m. The average porosity of thermal reservoir is 28%–35%, the permeability is(600–2000)×10^(-3) μm^(2), and the temperature of thermal reservoir is 70–110 ℃. The formation has total geothermal resources of 13.79×10^(18) J, equivalent to 4.70×10^(8) t of standard coal. Based on a large amount of seismic and drilling data from oil and gas exploration, this study carried out high quality target area selection, simulation of sandstone thermal reservoir, and production and injection in the same layer. The geothermal heating project with distributed production and injection well pattern covering an area of 230×10^(4) m^(2) was completed in the new district of Caofeidian in 2018. The project has been running steadily for two heating seasons, with an average annual saving of 6.06×10^(4) t of standard coal and a reduction of 15.87×10^(4) t of carbon dioxide, achieving good economic and social benefits. This project has proved that the Neogene sandstone geothermal reservoir in eastern China can achieve sustainable large-scale development by using the technology of "balanced production and injection in the same layer". It provides effective reference for the exploration and development of geothermal resource in oil and gas-bearing basins in eastern China.展开更多
Some useful layered cross product decompositons are derived both for general bit permutation networks and for(2n-1)-stage multistage interconnection networks.Several issues in related works are clarified and the rearr...Some useful layered cross product decompositons are derived both for general bit permutation networks and for(2n-1)-stage multistage interconnection networks.Several issues in related works are clarified and the rearrangeability of some interesting networks are considered.In particular, the rearrangeability of one class of networks is formulated as a new type of combinatorial design problmes.展开更多
A dynamic two-zone model is proposed to address the formation of granulation and drying zones in fluidized bed layering granulation processes with internal product classification. The model assumes a constant volume f...A dynamic two-zone model is proposed to address the formation of granulation and drying zones in fluidized bed layering granulation processes with internal product classification. The model assumes a constant volume for the granulation zone, but a variable overall volume for the fluidized bed to account for classified product removal. The model is used to study the effect of various process parameters on dynamics and process stability. Stability is shown to depend on the separation diameter of product removal and the flow rate of the injected liquid. A lower and upper range of separation diameters with stable process behavior are found. In an intermediate range instability in the form of self-sustained oscillations is observed. The lower stability boundary is in qualitative agreement with recent experimental observations (Schmidt, Bück, & Tsotsas, 2015); the upper boundary was reported in a theoretical paper by Vreman, Van Lare, and Hounslow (2009) based on a single zone model.展开更多
Powder bed fusion methods of additive manufacturing (AM) require consistent, reproducible, and uniform layers of powder for the reliable production of high-quality parts, where properties of powder are central to achi...Powder bed fusion methods of additive manufacturing (AM) require consistent, reproducible, and uniform layers of powder for the reliable production of high-quality parts, where properties of powder are central to achieving this. Among these properties, powder flowability and spreadability play critical roles in determining the quality of these powder layers.While extensive research has been conducted on powder flow and spreading behaviour, and on their characterisation, there is little critical comparison and review of these terms in the context of AM. Such a review is necessary to further develop and enhance our comprehension of spreading dynamics and its relation to powder properties in AM systems.This review paper aims to build a coherent understanding of the correlation between powder characteristics and spreading in powder based additive manufacturing and its impact on manufactured parts. It highlights the current progress in comprehending spreading dynamics, the influence of powder characteristics, environmental conditions, spreading system, and the development of testing tools to assess powder spreadability. Furthermore, the paper critically discusses the challenge of finding appropriate quantitative metrics and recent advances in the use of standardised methods for evaluating powder spreadability.展开更多
The corrosion behaviors of Al-brass in stagnant and flowing marine water as a function of combinative rare earths (Ce and La) ad-dition were investigated by electrochemical techniques, X-ray diffraction (XRD) and ...The corrosion behaviors of Al-brass in stagnant and flowing marine water as a function of combinative rare earths (Ce and La) ad-dition were investigated by electrochemical techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was demon-strated that RE elements could make the corrosion product layer more protective and strengthen the cohesion between the film and matrix in stagnant seawater. The electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) analysis confirmed that a duplex layer, which was mainly composed of an inner Al2O3 with trace amounts of RE compounds and an outer basic chloride of copper or zinc like (Cu, Zn)2Cl(OH)3, Cu(OH)Cl and CuCl2·3Cu(OH)2 layer was formed on RE-contained Al-brass surface and that the inner layer was responsible for the good corrosion resistance of the alloy. While only a porous and non-protective corrosion product layer was formed on the Al-brass alloy without RE addition, which made small values of the corrosion resistance. Additionally, in flowing marine water with velocity about 2 m/s, pitting corrosion occurred on the Al-brass surface and RE addition could availably decrease pitting sensitivity of the alloy.展开更多
Grounding devices are significant to the operation of the power transmission line and power equipment.The soil and leakage current can easily cause the corrosion of carbon steel grounding devices,resulting in power ac...Grounding devices are significant to the operation of the power transmission line and power equipment.The soil and leakage current can easily cause the corrosion of carbon steel grounding devices,resulting in power accidents.Therefore,most carbon steel grounding devices in service are already corroded,and the accurate calculation of grounding parameters for corroded grounding devices is important.However,most existing methods for calculating the grounding parameters of corroded grounding devices usually have the following disadvantages:1)They only consider whether the grounding devices are broken or not,and cannot analyze the grounding parameters of grounding devices with different corrosion degrees;2)They assume that the corroded grounding device is a conductor with a smaller diameter,and ignore the impact of the corrosion product layer,resulting in calculation errors.To solve the above problems,this paper establishes an accurate corrosion model for grounding devices based on the volume expansion coefficient of corrosion products.The grounding parameters calculation method for corroded grounding devices is proposed based on the boundary element method(BEM)and Galerkin’s method.Then the grounding performance of tower grounding grids with different corrosion degrees in different soils(uniform and layered)is analyzed.Finally,some features of grounding parameters of corroded grounding devices are given.This study can accurately calculate the grounding parameters of the corroded grounding devices and has far-reaching engineering significance for the safety of power equipment.展开更多
基金supported by the Gudong Oil Production Plant of Shengli Oilfield Subsidiary Company,China Postdoctoral Science Foundation(Project 2013M530681)Hubei Province Natural Science Foundation(Project 2013CFB394)
文摘Traditional fluid production profile logging is not usually suitable for heavy-viscous crude oil wells.Biodegradation of heavy oil can lead to the loss of n-alkanes,and the use of chromatogram fingerprint techniques in studying the production contributions of single layers in heavy oil commingled wells has limitations.However,aromatic compounds are relatively well preserved.We took the heavy oil commingled wells of small layers NG55 and NG61 in the ninth area of the Gudong oil field as examples.Based on the principle of chromatography,the whole-oil GC-MS was used,and the aromatic parameters which have a strongly linear relationship with the ratio of mixed two end member oils were verified and selected in laboratory.Studies showed that the ratio of (1,4,6-+ 2,3,6-trimethylnaphthalene) to 1,2,5-trimethylnaphthalene has a strongly linear relationship with the ratio of the mixed two end member oils (R2=0.992).The oil contributions from single layers NG55 and NG61 in six commingled heavy oil wells were calculated using established charts and this relationship.The calculated results are consistent with the results of long period dynamic monitoring and logging interpretation in the study area and can provide a scientific basis for monitoring production performance and hierarchical management of reservoirs.The study provides a new geochemical method for calculation of the contributions of single layers in heavy oil commingled wells when conventional fluid production profile logging is not suitable.
基金The authors acknowledge the Project(81472058)sup-ported by the National Natural Science Foundation of Chinathe financial support of the 2015 ShanDong province project of outstanding subject talent group.the project(LSD-KB1806)+2 种基金supported by the foundation of National Key labo-ratory of Shock Wave and Detonation Physics and the project(11802284)supported by the National Natural Science Foun-dation of China.The project(2017GK2120)supported by the Key Research and Development Program of Hunan Province and the Natural Science Foundation of Hunan Province of China(2018JJ2506).
文摘For high corrosion resistance and extensively modified biodegradable Mg-based alloys and composites for bone implants,a new Mgbased matrix model prepared by powder metallurgy is discussed and developed.In this research,Mg-5 wt.%Zn alloys were selected as a case.And they were impacted by hot extrusion and aging treatments to construct microstructure with different characteristics.Their selfforming corrosion product layer in Ringer’s solution,biodegradable behavior and corrosion mechanism were minutely investigated by in vitro degradation,electrochemical corrosion and cytocompatibility.The results demonstrated the extruded Mg-5 wt.%Zn alloy aged for 96 h showed high corrosion resistance,good biocompatibility for L929 and excellent ability of maintaining sample integrity during the immersion.Significantly,the alloy showed fine-grain microstructure and uniform distributed hundred nano-sized second phases,which promoted the formation of the uniform and smooth corrosion product layer at the beginning of immersion.The corrosion product layer was more stable in chloride containing aqueous solution and could be directly formed and repaired quickly,which effectively protected the matrix from further corrosion.In addition,an ideal model of Mg-based matrix for bone tissue engineering was tried to presume and propose by discussing the causal relationship between microstructure and bio-corrosion process.
文摘Packaging is one of the most important methods of keeping the quality of food products for storage, transportation and end-use. The price of materials employed for packaging food has traditionally been high and used to be more expensive than the food itself. Technological innovations made possible to produce packaging materials cheaply. One of these processes is known as co-extrusion. This technique makes a film with two or more layers with different plastics not laminating the layers together with an adhesive, eliminating the use of solvents and producing a film in just one step instead multiple steps. In this background, our paper relates to the evolution on packaging for foods by using patenting documents. A search for patent documents was performed on free patent databases using keywords and International Patent Classification (IPC) codes related to this technology. As results: (a) 17% of the 21,472 documents found are focused on multilayer packaging for food; (b) 12 countries hold more than 90% of patents (38% Japan; 23% The United States of America; 7% Canada and 6% Germany); and, (c) two peaks were perceived in the period of 1992-1994 and 2003, and matches, respectively, the Persian Gulf (1990-1991) and Iraq Wars (2003-invasion of Iraq), so the historical tendency is confirmed: "wars also generate scientific and technological innovations".
基金This study was supported and helped by Professor Yan Jiahong with China Petroleum Exploration and Development Research Institute,Yao Yanhua,Chief Geologist of the Hydrology Institute of PetroChina Liaohe Oilfield Company,and Dr.Kong Yanlong with the Institute of Geology and Geophysics,Chinese Academy of Sciences.
文摘Taking the Gaoshangpu-Liuzan geothermal field in the Nanpu sag of the Bohai Bay Basin as the research object, this paper discusses the geological conditions and potential of the geothermal resources of the Guantao Formation in the study area, and introduces the development practice of geothermal energy heating in Caofeidian. The average buried depth of the Guantao Formation is 1500–2500 m, the lithology is dominated by sandy conglomerate, and the average thickness of thermal reservoir is 120–300 m. The average porosity of thermal reservoir is 28%–35%, the permeability is(600–2000)×10^(-3) μm^(2), and the temperature of thermal reservoir is 70–110 ℃. The formation has total geothermal resources of 13.79×10^(18) J, equivalent to 4.70×10^(8) t of standard coal. Based on a large amount of seismic and drilling data from oil and gas exploration, this study carried out high quality target area selection, simulation of sandstone thermal reservoir, and production and injection in the same layer. The geothermal heating project with distributed production and injection well pattern covering an area of 230×10^(4) m^(2) was completed in the new district of Caofeidian in 2018. The project has been running steadily for two heating seasons, with an average annual saving of 6.06×10^(4) t of standard coal and a reduction of 15.87×10^(4) t of carbon dioxide, achieving good economic and social benefits. This project has proved that the Neogene sandstone geothermal reservoir in eastern China can achieve sustainable large-scale development by using the technology of "balanced production and injection in the same layer". It provides effective reference for the exploration and development of geothermal resource in oil and gas-bearing basins in eastern China.
文摘Some useful layered cross product decompositons are derived both for general bit permutation networks and for(2n-1)-stage multistage interconnection networks.Several issues in related works are clarified and the rearrangeability of some interesting networks are considered.In particular, the rearrangeability of one class of networks is formulated as a new type of combinatorial design problmes.
文摘A dynamic two-zone model is proposed to address the formation of granulation and drying zones in fluidized bed layering granulation processes with internal product classification. The model assumes a constant volume for the granulation zone, but a variable overall volume for the fluidized bed to account for classified product removal. The model is used to study the effect of various process parameters on dynamics and process stability. Stability is shown to depend on the separation diameter of product removal and the flow rate of the injected liquid. A lower and upper range of separation diameters with stable process behavior are found. In an intermediate range instability in the form of self-sustained oscillations is observed. The lower stability boundary is in qualitative agreement with recent experimental observations (Schmidt, Bück, & Tsotsas, 2015); the upper boundary was reported in a theoretical paper by Vreman, Van Lare, and Hounslow (2009) based on a single zone model.
基金support from EPSRC-UK Future Manufacturing Hub in Manufacture using Advanced Powder Processes(MAPP)(EP/P006566/1,www.mapp.ac.uk).
文摘Powder bed fusion methods of additive manufacturing (AM) require consistent, reproducible, and uniform layers of powder for the reliable production of high-quality parts, where properties of powder are central to achieving this. Among these properties, powder flowability and spreadability play critical roles in determining the quality of these powder layers.While extensive research has been conducted on powder flow and spreading behaviour, and on their characterisation, there is little critical comparison and review of these terms in the context of AM. Such a review is necessary to further develop and enhance our comprehension of spreading dynamics and its relation to powder properties in AM systems.This review paper aims to build a coherent understanding of the correlation between powder characteristics and spreading in powder based additive manufacturing and its impact on manufactured parts. It highlights the current progress in comprehending spreading dynamics, the influence of powder characteristics, environmental conditions, spreading system, and the development of testing tools to assess powder spreadability. Furthermore, the paper critically discusses the challenge of finding appropriate quantitative metrics and recent advances in the use of standardised methods for evaluating powder spreadability.
基金supported by the Science and Technology Payoffs Transformation Program of Jiangsu Province (DA2006034)the Program of National College Student Creative Experiment (081053309)
文摘The corrosion behaviors of Al-brass in stagnant and flowing marine water as a function of combinative rare earths (Ce and La) ad-dition were investigated by electrochemical techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was demon-strated that RE elements could make the corrosion product layer more protective and strengthen the cohesion between the film and matrix in stagnant seawater. The electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) analysis confirmed that a duplex layer, which was mainly composed of an inner Al2O3 with trace amounts of RE compounds and an outer basic chloride of copper or zinc like (Cu, Zn)2Cl(OH)3, Cu(OH)Cl and CuCl2·3Cu(OH)2 layer was formed on RE-contained Al-brass surface and that the inner layer was responsible for the good corrosion resistance of the alloy. While only a porous and non-protective corrosion product layer was formed on the Al-brass alloy without RE addition, which made small values of the corrosion resistance. Additionally, in flowing marine water with velocity about 2 m/s, pitting corrosion occurred on the Al-brass surface and RE addition could availably decrease pitting sensitivity of the alloy.
基金supported by the Fundamental Research Funds for the Central Universities(grant no.2019CDXYDQ0010)the National Key Research and Development Program of China(grant no.2017YFB0902701)the National Natural Science Foundation of China(grant no.51577017).
文摘Grounding devices are significant to the operation of the power transmission line and power equipment.The soil and leakage current can easily cause the corrosion of carbon steel grounding devices,resulting in power accidents.Therefore,most carbon steel grounding devices in service are already corroded,and the accurate calculation of grounding parameters for corroded grounding devices is important.However,most existing methods for calculating the grounding parameters of corroded grounding devices usually have the following disadvantages:1)They only consider whether the grounding devices are broken or not,and cannot analyze the grounding parameters of grounding devices with different corrosion degrees;2)They assume that the corroded grounding device is a conductor with a smaller diameter,and ignore the impact of the corrosion product layer,resulting in calculation errors.To solve the above problems,this paper establishes an accurate corrosion model for grounding devices based on the volume expansion coefficient of corrosion products.The grounding parameters calculation method for corroded grounding devices is proposed based on the boundary element method(BEM)and Galerkin’s method.Then the grounding performance of tower grounding grids with different corrosion degrees in different soils(uniform and layered)is analyzed.Finally,some features of grounding parameters of corroded grounding devices are given.This study can accurately calculate the grounding parameters of the corroded grounding devices and has far-reaching engineering significance for the safety of power equipment.