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A homogenous microstructural Mg-based matrix model for orthopedic application with generating uniform and smooth corrosion product layer in Ringer’s solution:Study on biodegradable behavior of Mg-Zn alloys prepared by powder metallurgy as a case 被引量:5
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作者 Yang Yan Xin Chu +7 位作者 Xier Luo Xuemei Xu Yu Zhang YiLong Dai Ding Li Liangjian Chen Tao Xiao Kun Yu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2021年第1期225-240,共16页
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
关键词 Magnesium alloys Powder metallurgy Second phase Corrosion product layer Biodegradable behavior CYTOCOMPATIBILITY
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Characteristics of Corrosion Product Layer Formed on Weathering Steel Exposed to the Tropical Climate of Vietnam 被引量:3
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作者 Le Thi Hong Lien Hoang Lam Hong 《Materials Sciences and Applications》 2013年第7期6-16,共11页
The weathering steel (Corten B) was exposed to out-door atmosphere of Hanoi (urban site) and Donghoi (marine site). The results showed the protective ability of corrosion product layer formed on weathering steel in th... The weathering steel (Corten B) was exposed to out-door atmosphere of Hanoi (urban site) and Donghoi (marine site). The results showed the protective ability of corrosion product layer formed on weathering steel in the initial stage. The SEM-EDX analysis detected the presence of chromium and copper in the inner layers of corrosion product formed on weathering steel. These elements improved corrosion resistance of corrosion product layers. In addition, the dense α-FeOOH phase were appeared early in corrosion product which is detected by X-ray diffraction and Micro Raman investigations. The results of polarization and EIS measurements also demonstrated the protectiveness of the corrosion product of weathering steel. 展开更多
关键词 WEATHERING Steel Corrosion product layer Protectiveness EXPOSED to INNER layer Outer layer
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Characteristic of solid product layer of MgSO in the reaction of MgO with SO2 被引量:2
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作者 LI ZhenShan, FANG Fan & CAI NingSheng Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084, China 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第7期1869-1876,共8页
The microstructure, nucleation and growth of MgSO4 product layer during the reaction of MgO single crystal with SO2 and O2 were investigated with thermo gravity analyzer (TGA) and atomic force microscopy (AFM). The AF... The microstructure, nucleation and growth of MgSO4 product layer during the reaction of MgO single crystal with SO2 and O2 were investigated with thermo gravity analyzer (TGA) and atomic force microscopy (AFM). The AFM images indicated that three dimensional islands with different sizes were formed during the initial reaction stage. At the initial stage, cone-shaped islands were formed, and most of them appeared at the position with terrace-step-kink. With the reaction time increasing, small islands would grow to large islands, and the coalescent would happen during this growth stage. During the product layer growth stage, the space and surface between islands would be occupied by islands, and continuum islands were formed. With the reaction time increasing in the product layer growth stage, the size of island increased while the number and total surface of all islands decreased. 展开更多
关键词 GAS-SOLID REACTION SOLID product layer ISLAND diffusion
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Optimization methods of production layer combination for coalbed methane development in multi-coal seams 被引量:2
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作者 YANG Zhaobiao ZHANG Zhengguang +5 位作者 QIN Yong WU Congcong YI Tongsheng LI Yangyang TANG Jun CHEN Jie 《Petroleum Exploration and Development》 2018年第2期312-320,共9页
Based on the productivity equation of coalbed methane(CBM) wells, three indexes, main production layer optimization index, main production layer expansion index and capacity contribution index are proposed, with which... Based on the productivity equation of coalbed methane(CBM) wells, three indexes, main production layer optimization index, main production layer expansion index and capacity contribution index are proposed, with which the three-step optimization method of production-layer combination is established. In selecting main production layer, the coal seam thickness, CBM content, coal seam permeability, coal seam reservoir pressure and coal structure are considered comprehensively to evaluate the potential of the production layer. In selecting expansion of the main production layer combination, on the premise of ensuring full and slow desorption of the main production layer and non-exposure of the main production layer out of liquid surface, the degree of mutual interference between the main and non-main production layers is comprehensively evaluated by coupling the critical desorption pressure, layer spacing and reservoir pressure gradient difference. In optimizing production layer combination, the main concern is the economic efficiency of the combined layers. Only when the contribution coefficient of the main production layer is greater than 30% and the contribution index of the other production layers is more than 10%, the economic benefit of a CBM well after being put into production can be ensured. Based on the comparative analysis of the development effect of the development test wells in Songhe of Guizhou province, it is proved that the "three-step method" for the optimization of production-layer combination is scientific and practical, and can be used to design the multi-layer commingling scheme of coalbed methane. 展开更多
关键词 CBM MULTI-layer commingled productION selection of main productION layer COMBINATION optimization productION CONTRIBUTION
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Calculating single layer production contribution of heavy oil commingled wells by analysis of aromatic parameters in whole-oil GC-MS
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作者 Xu Yaohui Ma Li +3 位作者 Li Linxiang Cui Wenfu Cheng Xiaowei Wang Xiaoping 《Petroleum Science》 SCIE CAS CSCD 2014年第1期89-96,共8页
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
关键词 Whole-oil GC-MS aromatic parameters commingled producing wells single layer production the ninth area of the Gudong oilfield
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Theoretical Study on Quantitative Characterization of Interlayer Interference in Multi-Layer Commingled Production 被引量:1
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作者 Pengfei Mu Shaopeng Wang +2 位作者 Jie Tan Hanqing Zhao Li’an Zhang 《Journal of Power and Energy Engineering》 2021年第4期21-29,共9页
X oilfield is a typical layered reservoir with a large vertical span and many oil-bearing formations. There are significant differences in reservoir types and fluid properties among various formations. The interlayer ... X oilfield is a typical layered reservoir with a large vertical span and many oil-bearing formations. There are significant differences in reservoir types and fluid properties among various formations. The interlayer interference is severe in the development process. At present, the interlayer interference research based on dynamic monitoring data cannot meet development adjustment needs. Combined with the field test results, through the indoor physical simulation experiment method, dynamic inversion method, and reservoir engineering method, this paper analyzes the main control factors and interference mechanism of interlayer interference, studies the variation law of interference coefficient, improves and forms the quantitative characteristic Theory of interlayer interference in multi-layer commingled production, and provides theoretical guidance for the total adjustment of the middle strata division in the oilfield. 展开更多
关键词 Thin Interbedded Reservoir Multi-layer production Interbedded Interference Quantitative Characterization Theoretical Research
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Technological Development on Layered Products for Foods and/or Foodstuff-Evaluation by Patenting Documents
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作者 M. E. M. Martinez P. C. Reis +1 位作者 D. A. Santos E. Winter 《Journal of Food Science and Engineering》 2011年第2期100-110,共11页
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
关键词 Multilayer packaging for food layered products for foods patent documents technological mapping.
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Intercalation Assembly and Chemical Product Engineering of Layered Intercalated Functional Materials Based on Efficient Utilization of Magnesium Resources in Salt Lakes
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作者 LIN Yanjun NING Bo +1 位作者 LI Kaitao WU Qin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期347-349,共3页
1 Introduction Magnesium salts are very important by-product of salt lake industry in West China.Nearly 200 million cubic meters of waste brine are released to the environment
关键词 layered intercalated functional materials Intercalation assembly chemical product engineering magnesium resources salt lakes
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On an Application of the Improved Maximum Product Criterion to Inverse Acoustic Scattering in a Layered Medium 被引量:1
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作者 Fermin S. Viloche Bazán Juliano de Bem Francisco +2 位作者 Koung Hee Leem George Pelekanos Vassilios Sevroglou 《Journal of Applied Mathematics and Physics》 2021年第4期661-682,共22页
In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well kn... In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well known <em>factorization method</em>, in which a computationally effective numerical scheme for the reconstruction of the shape of the scatterer is presented. This is possible, due to a <em>mixed reciprocity principle</em>, which renders the computation of the Green function at the background medium unnecessary. Moreover, to further refine our inversion algorithm, an efficient Tikhonov parameter choice technique, called <em>Improved Maximum Product Criterion</em> (IMPC) is exploited. Our regularization parameter is computed via a fast iterative algorithm which requires no <em>a priori</em> knowledge of the noise level in the far-field data. Finally, the effectiveness of IMPC is illustrated with various numerical examples. 展开更多
关键词 Acoustic Scattering layered Medium Mixed Reciprocity Relation Factorization Method Improved Maximum product Criterion (IMPC)
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The Influence of Selection for Plasma very Low Density Lipoprotein Concentration upon Production Performance in Layer Type Chickens
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作者 Li Hui, Yang Shan (Northeast Agricultural University, Harbin, 150030 PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1997年第2期95-102,共8页
The chickens studied were from a pure line of brown shell egg-type (YAFA) female grandparents of 17-week-old. Plasima very low density lipoprotein (VLDL) concentration was measured with turbidimetric assay. The experi... The chickens studied were from a pure line of brown shell egg-type (YAFA) female grandparents of 17-week-old. Plasima very low density lipoprotein (VLDL) concentration was measured with turbidimetric assay. The experiment results showed that the phenotypic correlations between 29-week or 50-week plasma VLDL concentration and egg production (EP) were positive in the early stage of laying period, but those in the latter stage were negative. Selection for low plasma VLDL concentration will decrease the EP in the early stage of laying period but increase the one in the latter stage. There was a significant negative phenotypic correlation between the age at first egg (AFE) and 18-week body weight (BW). The phenotypic correlation between 29-week plasma VLDL concentration and the AFE was negative. AFE was influenced by BW and body fatness as well. There was significant positive phenotypic correlation between plasima VLDL concentration and body weights (BWs) at the same stage in laying period and the phenotypic correlation was also positive between 29-week plasma VLDL concentration and the BW at middle stage of laying period, indicating that selection for low plasma VLDL concentration would reduce BWs at various stages to different degree. 展开更多
关键词 layer type chicken plasma VLDL concentration production performance
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Effects of Stokes production on summer ocean shelf dynamics 被引量:1
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作者 ZHANG Xuefeng HANGuijun +1 位作者 WANG Xidong ZHANG Lianxin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第1期24-34,共11页
A two-dimensional numerical model,which is configured on the basis of Princeton ocean model(POM),is used to study the effect of Stokes production(SP) of the turbulent kinetic energy on a density profile and Ekman ... A two-dimensional numerical model,which is configured on the basis of Princeton ocean model(POM),is used to study the effect of Stokes production(SP) of the turbulent kinetic energy on a density profile and Ekman transport in an idealized shelf region in summer.The energy input from SP is parameterized and included into the Mellor-Yamada turbulence closure submodel.Results reveal that the intensity of wind-driven upwelling fronts near the sea surface is weakened by the SP-associated turbulent kinetic energy input.The vertical eddy viscosity coefficient in the surface boundary layer is enhanced greatly owing to the impact of SP,which decreases the alongshore velocity and changes the distribution of upwelling.In addition,the SP-induced mixing easily suppresses the strong stratification and significantly increases the depth of the upper mixed layer(ML) under strong winds. 展开更多
关键词 Stokes production POM upper mixed layer UPWELLING
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Relation between oxidation microstructure and the maximum energy product loss of a Sm_2Co_(17) magnet oxidized at 500℃ 被引量:1
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作者 刘丽丽 蒋成保 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期416-420,共5页
The oxidation microstructure and maximum energy product (BH)max loss of a 8m(Co0.76, Fe0.1, Cu0.1, Zr0.04)7 magnet oxidized at 500 ℃ were systematically investigated. Three different oxidation regions were formed... The oxidation microstructure and maximum energy product (BH)max loss of a 8m(Co0.76, Fe0.1, Cu0.1, Zr0.04)7 magnet oxidized at 500 ℃ were systematically investigated. Three different oxidation regions were formed in the oxidized magnet: a continuous externM oxide scale, an internal reaction layer, and a diffusion zone. Both room-temperature and high-temperature (BH)max losses exhibited the same parabolic increase with oxidation time. An oxygen diffusion model was proposed to simulate the dependence of (BH)max loss on oxidation time. It is found that the external oxide scale has little effect on the (BH)max loss, and both the internal reaction layer and diffusion zone result in the (BH)max loss. Moreover, the diffusion zone leads to more (BH)max loss than the internal reaction layer. The values of the oxidation rate constant k for internal reaction layer and oxygen diffusion coefficient D for diffusion zone were obtained, which are about 1.91×10^-10 cm^2/s and 6.54×10^-11 cm^2/s, respectively. 展开更多
关键词 Sm2Co17 magnet maximum energy product loss internal reaction layer diffusion zone
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Analysis of the VWP Product Characteristics in One Strong Rainstorm Process
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作者 TANG Ming-hui CHEN De-qiao +1 位作者 ZHANG Hai YI Zhong-hai 《Meteorological and Environmental Research》 CAS 2011年第8期23-25,32,共4页
[Objective] The aim was to study the characteristics in VWP period characteristics in one strong rainstorm process.[Method] Based on the previous studies,the VWP product characteristics in early period of strong rains... [Objective] The aim was to study the characteristics in VWP period characteristics in one strong rainstorm process.[Method] Based on the previous studies,the VWP product characteristics in early period of strong rainstorm,during the development and the end period in Hunan Province on April 8,2008 were studied.[Result] Before the occurrence of rainstorm,the destruction of low layer 'ND' layer indicated the increase of water vapor content layer.The intrusion of cold and dry air in the middle layer led to unstable layer;during the maintaining period of rainstorm,the strong vertical shear in the low layer led to the occurrence of strong rainstorm.The cold air in the boundary layer penetrated and led the rainstorm to the most prevailing stage.There was hailstorm on the ground.Before the disappearance of rainstorm(after 17:59),the entire wind field changed into consecutive 'ND' layer and it suggested that the strong convective cloud was far away from the location of radar,and indicated the end of rainstorm.[Conclusion] The study provided reference and basis for the pre-warning of rainstorm for temporary reporter. 展开更多
关键词 Strong rainstorm VWP product 'ND' layer Characteristics analysis China
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基于大食物观的草地农业发展趋势及关键科学问题
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作者 侯扶江 李岚 +5 位作者 宁娇 娄珊宁 李春杰 沈禹颖 南志标 任继周 《中国科学基金》 CSSCI CSCD 北大核心 2024年第4期647-657,共11页
大食物观下,国家食物安全的重点是饲料粮安全。草地农业是全球最重要的食物生产系统之一,既直接生产草畜产品,又间接地为食物生产提供生态保障,满足国家对食物安全、生态安全和边疆稳定不断增长的刚性需求。目前,草地农业保障国家食物... 大食物观下,国家食物安全的重点是饲料粮安全。草地农业是全球最重要的食物生产系统之一,既直接生产草畜产品,又间接地为食物生产提供生态保障,满足国家对食物安全、生态安全和边疆稳定不断增长的刚性需求。目前,草地农业保障国家食物安全的水平亟待提高,支撑国家高质量发展的能力亟待加强。种子是草地农业的物质基础,天然草原和栽培草地(也称“人工草地”)是草地农业生产食物的主要基地,草地保护为草地农业开展食物生产“保驾护航”,草地农业系统耦合促进食物生产的效益放大。草地农业是基础性战略产业,保障国家食物安全的水平依靠基础研究的创新。为此,本文分析了草类种质资源挖掘利用与种子生产控制、牧草优质高产栽培与转化、草原生态生产力维持与修复、草地有害生物管理、草地农业系统耦合与管理等5个方面的研究进展,并提出对应的关键科学问题。 展开更多
关键词 草原 栽培草地 种质资源 生物灾害 生产层 界面 系统耦合 草业科学
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硼硅酸盐生物活性玻璃的矿化及机理初探
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作者 周杰 王会 +3 位作者 崔旭 黄文旵 王德平 周萘 《生物骨科材料与临床研究》 CAS 2024年第3期1-7,共7页
目的探讨硼硅酸盐生物活性玻璃体外矿化成类骨层状结构的机理。方法模拟体内环境,将硅酸盐玻璃(0B)、硼硅酸盐玻璃(2B)和硼酸盐玻璃(3B)浸泡于SBF溶液和含有明胶的SBF溶液中1周;随后采用质量损失分析、SEM、EDS、XRD及FTIR等测试方法对... 目的探讨硼硅酸盐生物活性玻璃体外矿化成类骨层状结构的机理。方法模拟体内环境,将硅酸盐玻璃(0B)、硼硅酸盐玻璃(2B)和硼酸盐玻璃(3B)浸泡于SBF溶液和含有明胶的SBF溶液中1周;随后采用质量损失分析、SEM、EDS、XRD及FTIR等测试方法对多种生物活性玻璃的矿化产物进行系统分析与比较;采用固体核磁NMR对生物玻璃进行玻璃结构分析。结果浸泡1周后,SEM观察到硼硅酸盐玻璃(2B)和不含硅的硼酸盐玻璃(3B)表面产生层状矿化产物,而硅酸盐玻璃(0B)表面只有一层矿化产物层;XRD和FTIR结果显示3种玻璃的表面产物均为含有部分羟基磷灰石的钙磷化合物;固体核磁波谱(11B)测试结果表明硼硅酸盐玻璃(2B)和不含硅的硼酸盐玻璃(3B)都存在大量[BO_(3)]平面三角体。最后,当硼硅酸盐玻璃(2B)浸泡在含有明胶的SBF溶液后,其矿化产物仍能维持层状结构;通过EDS分析可知形成明胶有机层和含羟基磷灰石的无机层相互堆积的特殊层状结构。结论2B和3B玻璃内部存在大量[BO_(3)]平面三角体所构造的二维平面结构。矿化过程中,不溶性反应物沉积在二维平面结构上,从而使矿化产物呈现层状结构。在浸泡液中添加一定量的明胶后,其可以有效地与硼硅酸盐玻璃的层状矿化结构相互匹配结合,最终堆叠形成有机相层与无机层相互交错的特殊结构。 展开更多
关键词 硼硅酸盐生物活性玻璃 骨修复材料 矿化产物 层状结构
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榆树林油田CCUS采油工程方案优化设计与实践 被引量:2
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作者 才庆 张丹丹 +2 位作者 张华春 孙维娜 刘慧 《大庆石油地质与开发》 CAS 北大核心 2024年第1期135-141,共7页
大庆榆树林油田扶杨油层属低孔、特低渗透储层,针对以往开发过程中存在注水困难、压裂有效期短、水驱开发难以有效动用的问题,开展CO_(2)驱油技术现场试验。从经济性、技术适应性、配套工艺成熟性等角度对采油工程方案进行综合评价,优... 大庆榆树林油田扶杨油层属低孔、特低渗透储层,针对以往开发过程中存在注水困难、压裂有效期短、水驱开发难以有效动用的问题,开展CO_(2)驱油技术现场试验。从经济性、技术适应性、配套工艺成熟性等角度对采油工程方案进行综合评价,优选出单、双管分层注入工艺、高气液比举升工艺、注采两端个性化防腐工艺及物理化学组合解冻堵工艺等CCUS采油工程技术。结果表明:试验区投产初期及目前生产情况均达到了油藏预测指标;采出井平均泵效及检泵周期与外围油田平均水平相持平,注气井与采出井腐蚀速率小于行业指标;实现CO_(2)有效埋存108.9×10^(4) t,比水驱预测采出程度提高采收率4.39百分点,取得较好的驱油开发效果。研究成果为CCUS示范区的高效建设提供了技术支撑,开辟了大庆油田外围难采储量有效动用的新途径。 展开更多
关键词 榆树林油田 CCUS 采油工程方案 分层注气 高气液比举升 防腐 防窜解堵
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Early Stage Hydration Mechanism of Cellulose Ether Modified Thin Layer Cement Pastes 被引量:8
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作者 马保国 SU Lei +1 位作者 JIAN Shouwei SONG Xuefeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第6期1172-1176,共5页
The early stage hydration mechanism of cellulose ether modified thin layer cement pastes was studied, using brick as the matrix. Samples of 6 h, 24 h, and 3 d and 7 d hydration time were analyzed to study the hydratio... The early stage hydration mechanism of cellulose ether modified thin layer cement pastes was studied, using brick as the matrix. Samples of 6 h, 24 h, and 3 d and 7 d hydration time were analyzed to study the hydration law on the surface of high water-absorbing matrix. Hydration products were qualitatively and semi-quantitatively analyzed using XRD, TG-DSC-DTG, FTIR and SEM. The experimental results show that there is no enough water for 2 mm thick cement pastes to hydrate, because of rapid water absorption of matrix. Trace amounts of Ca (OH)2 was detected after three days hydration. With the prolongation of hydration time, the category and concentration of hydration products do not change. Compared with 2 mm thick cement pastes, 6 mm thick cement pastes and 10 mm thick cement pastes have lower dehydration rate and water loss. The humidity field of the cement paste show different changes within the same time. 6 mm thick cement paste and 10 mm thick cement pastes have longer time and more water to hydrate. Ca(OH)2 and ettringite were detected after 6 hours hydration and the concentrations of hydration products increased from 24 hours to 7 days. 展开更多
关键词 cellulose ether thin layer cement pastes high water-absorbing matrix hydration products
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黄芩提取物对热应激蛋鸡产蛋性能、蛋品质和免疫功能的影响
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作者 周昊 况丹 《中国饲料》 北大核心 2024年第20期35-38,共4页
文章旨在探讨黄芩提取物对热应激蛋鸡产蛋性能、蛋品质和免疫功能的影响。试验将600只产蛋性能相近、70周龄左右的健康罗曼粉蛋鸡随机分为5组,每组8个重复,每个重复15只。其中对照组和热应激组分别饲喂基础日粮。试验Ⅰ、Ⅱ和Ⅲ组分别... 文章旨在探讨黄芩提取物对热应激蛋鸡产蛋性能、蛋品质和免疫功能的影响。试验将600只产蛋性能相近、70周龄左右的健康罗曼粉蛋鸡随机分为5组,每组8个重复,每个重复15只。其中对照组和热应激组分别饲喂基础日粮。试验Ⅰ、Ⅱ和Ⅲ组分别在基础日粮中添加15、30和60 mg/kg黄芩苷提取物的,试验为期9周。结果表明:1~3周,试验Ⅱ和Ⅲ组蛋鸡产蛋率较热应激组分别显著提高8.27%和11.92%(P<0.05),料蛋比显著降低7.21%和9.34%(P<0.05),软破蛋率分别显著降低7.38%和26.57%(P<0.05);4~6周,试验Ⅱ和Ⅲ组蛋鸡产蛋率较热应激组分别显著提高11.35%和10.98%(P<0.05),料蛋比显著降低10.50%和10.45%(P<0.05),软破蛋率分别显著降低15.33%和16.11%(P<0.05);7~9周,试验Ⅱ和Ⅲ组蛋鸡产蛋率较热应激组分别显著提高4.08%和7.71%(P<0.05),料蛋比显著降低2.95%和6.01%(P<0.05),软破蛋率分别显著降低14.09%和15.28%(P<0.05)。试验Ⅱ和Ⅲ组蛋壳强度较热应激组显著提高(P<0.05),试验Ⅲ组哈氏单位较热应激组显著提高(P<0.05),试验Ⅱ和Ⅲ组蛋粗蛋白质和钙含量较热应激组显著提高(P<0.05),试验Ⅱ和Ⅲ组蛋鸡血清白细胞介素-10(IL-10)和肿瘤坏死因子α(TNF-α)含量显著降低(P<0.05),免疫球蛋白A(IgA)和免疫球蛋白G(IgG)含量显著提高(P<0.05);总之,试验数据显示,补充黄芩提取物(60 mg/kg)可通过增强热应激蛋鸡免疫力提高蛋鸡生产性能,改善蛋品质。 展开更多
关键词 热应激 黄芩提取物 蛋鸡 生产性能 蛋品质 免疫功能
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光致变色纱线在多层织物设计中的应用
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作者 牛建涛 刘雨晴 +2 位作者 黄紫娟 徐超武 蒋秀翔 《毛纺科技》 CAS 北大核心 2024年第1期15-18,共4页
为了丰富织物的多样性,利用光致变色纱线,结合表里换层双层组织,设计与开发了“P”字图案表里换层光致变色面料;并进一步设计与开发了上、中层表里换层结构的“E”字图案三层组织光致变色面料,实现了织物在光线照射下单面变色,而反面不... 为了丰富织物的多样性,利用光致变色纱线,结合表里换层双层组织,设计与开发了“P”字图案表里换层光致变色面料;并进一步设计与开发了上、中层表里换层结构的“E”字图案三层组织光致变色面料,实现了织物在光线照射下单面变色,而反面不显变色的特殊效果。将光致变色纱线与表里换层结构的双层或多层织物相结合,可以形成新型光致变色功能面料,为此类产品的开发与设计提供了一种新思路。 展开更多
关键词 光致变色 表里换层 多层织物 产品设计
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CLEAN PRODUCTION AND SMELTING REDUCTION TECHNOLOGY
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作者 Wang Lixin, Xu Zhihong and Yang Zhangyuan (Laboratory of Computer Chemistry (LCC), Institute of Chemical Metallurgy, Chineses Academy of Sciences, Beijing 100080) 《化工学报》 EI CAS CSCD 北大核心 2000年第S1期159-162,共4页
Clean Production is the best method for iron-steel making industry to eliminate pollution thoroughly. In order to achieve this object, smelting reduction technology should play the key role. Furthermore, process integ... Clean Production is the best method for iron-steel making industry to eliminate pollution thoroughly. In order to achieve this object, smelting reduction technology should play the key role. Furthermore, process integration method can be used to solve the problem of residual gas utilization by integrating smelting reduction process with direct reduced iron unit, gasoline, methanol or dimethyl ether synthesis unit, etc. A new smelting reduction process has been proposed which can be constructed on the present plant site. Since this process can directly treat the lump coal and iron ore fines, it reduces st6ps necessary in traditional blast furnace process and Corex smelting reduction process. 展开更多
关键词 Clean production Smelting reduction Process integration Multi-layer fluidized moving bed Coal gas utilization Blast furnace
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