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Analysis of morphological characteristics of gravels based on digital image processing technology and self-organizing map 被引量:1
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作者 XU Tao YU Huan +4 位作者 QIU Xia KONG Bo XIANG Qing XU Xiaoyu FU Hao 《Journal of Arid Land》 SCIE CSCD 2023年第3期310-326,共17页
A comprehensive understanding of spatial distribution and clustering patterns of gravels is of great significance for ecological restoration and monitoring.However,traditional methods for studying gravels are low-effi... A comprehensive understanding of spatial distribution and clustering patterns of gravels is of great significance for ecological restoration and monitoring.However,traditional methods for studying gravels are low-efficiency and have many errors.This study researched the spatial distribution and cluster characteristics of gravels based on digital image processing technology combined with a self-organizing map(SOM)and multivariate statistical methods in the grassland of northern Tibetan Plateau.Moreover,the correlation of morphological parameters of gravels between different cluster groups and the environmental factors affecting gravel distribution were analyzed.The results showed that the morphological characteristics of gravels in northern region(cluster C)and southern region(cluster B)of the Tibetan Plateau were similar,with a low gravel coverage,small gravel diameter,and elongated shape.These regions were mainly distributed in high mountainous areas with large topographic relief.The central region(cluster A)has high coverage of gravels with a larger diameter,mainly distributed in high-altitude plains with smaller undulation.Principal component analysis(PCA)results showed that the gravel distribution of cluster A may be mainly affected by vegetation,while those in clusters B and C could be mainly affected by topography,climate,and soil.The study confirmed that the combination of digital image processing technology and SOM could effectively analyzed the spatial distribution characteristics of gravels,providing a new mode for gravel research. 展开更多
关键词 self-organizing map digital image processing morphological characteristics multivariate statistical method environmental monitoring
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Effect of thermal processing and fermentation with Chinese traditional starters on characteristics and allergenicity of wheat matrix 被引量:1
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作者 Huan Rao Xi Li Wentong Xue 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期789-794,共6页
Wheat allergy has become a serious health threat worldwide and its prevalence has increased alarmingly in the past few years.Factors such as food matrix and food processing may alter the structure of wheat proteins,an... Wheat allergy has become a serious health threat worldwide and its prevalence has increased alarmingly in the past few years.Factors such as food matrix and food processing may alter the structure of wheat proteins,and hence affect its allergenic properties.However,few reports have focused on the influence of Chinese traditional starter fermentation on wheat allergy.In this study,5 starters from different regions of China were used for fermentation,and protein characteristics were monitored by sodium dodecyl sulfate polyacrylamide gel electropheresis,and immunoreactivity analyzed by immunoassay with allergenic serum was obtained from New Zealand white rabbits.The allergenicity of steamed and baked matrices was also evaluated.The results showed that the allergenicity of wheat dough was basically increased at the beginning and then decreased during fermentation,but specific trends depend on different starters.With the progress of fermentation,especially as pH value decreased to 3.0-4.0,the allergenicity decreased significantly.Baking and steaming can reduce the allergenicity of wheat matrix,but fermentation is not a key factor affecting the allergenic activity of proteins.Our results can provide a theoretical basis for controlling wheat allergenicity in food proces sing or producing hypoallergenic food. 展开更多
关键词 Chinese traditional starter ermentation characteristics Thermal processing ALLERGENICITY Wheat matrix
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Sedimentary Processes and Depositional Characteristics of Coarse-grained Subaqueous Fans along Steep Slopes in a Lacustrine Rift Basin:A Case Study from the Dongying Depression,Bohai Bay Basin,China
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作者 YANG Baoliang QIU Longwei +3 位作者 YANG Yongqiang Kouassi Louis KRA DONG Daotao Danish KHAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期526-547,共22页
Coarse-grained subaqueous fans are vital oil and gas exploration targets in the Bohai Bay basin,China.The insufficient understanding of their sedimentary processes,depositional patterns,and controlling factors restric... Coarse-grained subaqueous fans are vital oil and gas exploration targets in the Bohai Bay basin,China.The insufficient understanding of their sedimentary processes,depositional patterns,and controlling factors restricts efficient exploration and development.Coarse-grained subaqueous fans in the Yong′an area,Dongying Depression,are investigated in this study.These fans include nearshore subaqueous fans,and sublacustrine fans,and their sedimentary processes,depositional patterns and distribution characteristics are mainly controlled by tectonic activity and paleogeomorphology.Nearshore subaqueous fans developed near the boundary fault during the early–middle deposition stage due to strong tectonic activity and large topographic subsidence.Early sublacustrine fans developed at the front of the nearshore subaqueous fans in the area where the topography changed from gentle to steep along the source direction.While the topography was gentle,sublacustrine fans did not develop.During the late weak tectonic activity stage,late sublacustrine fans developed with multiple stages superimposed.Frequent fault activity and related earthquakes steepened the basin margin,and the boundary fault slopes were 25.9°–34°.During the early–middle deposition stage,hyperpycnal flows triggered by outburst floods developed.During the late deposition stage,with weak tectonic activity,seasonal floods triggered hyperpycnal flows,and hybrid event beds developed distally. 展开更多
关键词 sedimentary processes depositional characteristics paleogeomorphology coarse-grained subaqueous fan lacustrine rift basin Dongying Depression
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Effects of Heat Treatment on Processing Characteristics of Pork
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作者 Ting BAI Li TANG +5 位作者 Lei WANG Ying ZHANG Bowen ZAN Wei WANG Lili JI Jiamin ZHANG 《Agricultural Biotechnology》 CAS 2023年第5期67-74,共8页
[Objectives]This study was conducted to explore the effects of heat treatment on processing characteristics of pork.[Methods]The effects of low-temperature long-term cooking(LTLT),high-temperature vacuum cooking,high-... [Objectives]This study was conducted to explore the effects of heat treatment on processing characteristics of pork.[Methods]The effects of low-temperature long-term cooking(LTLT),high-temperature vacuum cooking,high-temperature cooking and high-temperature steaming on some indexes of pork products were studied,and principal component analysis was carried out.[Results]LTLT had significant effects on the total sensory score,moisture content,cooking loss rate,a value,shear force,and TBARS of pork,and the corresponding optimal product indicators were 71.40 points,72.36%,14.20%,4.79,7089.87 g,and 0.05 mg/kg,respectively.The microstructure changes in the LTLT group were relatively small,as the muscle fiber structure was relatively dense and uniform,and the gaps between muscle fibers were small.A total of 30 volatile flavor compounds were detected in the four groups,mainly alcohols,alkenes,alkanes,lipids,ketones,and aldehydes,and the LTLT group had more types and high contents.PCA analysis showed that the sensory evaluation,moisture content,elasticity,a value and LTLT were positively correlated with principal component 1.[Conclusions]Various indexes comprehensively showed that the LTLT group had better meat color,flavor,texture characteristics and lower oxidation degree than traditional cooking and steaming methods,which provides a theoretical reference for its large-scale application in the processing of prepared meat products. 展开更多
关键词 Heat treatment PORK processing characteristics Principal component analysis
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Failure process and monitoring data of an extra-large landslide at the Nanfen Open-pit Iron Mine
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作者 WANG Jingxiang YANG Xiaojie +2 位作者 TAO Zhigang HE Manchao SHEN Fuxin 《Journal of Mountain Science》 SCIE CSCD 2024年第9期2918-2938,共21页
An extra-large landslide occurred on June 19,2021,on the footwall slope of the Nanfen Open-pit Iron Mine in Liaoning Province,China,with a volume of approximately 1.2×107 m3.To elucidate the causative factors,dev... An extra-large landslide occurred on June 19,2021,on the footwall slope of the Nanfen Open-pit Iron Mine in Liaoning Province,China,with a volume of approximately 1.2×107 m3.To elucidate the causative factors,development process,and destructive mechanisms of this catastrophic landslide,comprehensive field tests,investigations,and laboratory experiments were conducted.Initially,the heavily weathered rock mass of the slope was intersected by faults and joint fissures,facilitating rainwater infiltration.Moreover,the landslide contained a substantial clay mineral with highly developed micro-cracks and micro-pores,exhibiting strong water-absorption properties.As moisture content increased,the rock mass underwent softening,resulting in reduced strength.Ultimately,continuous heavy rainfall infiltration amplified the slope's weight,diminishing the weak structural plane's strength,leading to fracture propagation,slip plane penetration,and extensive tensile-shear and uplift failure of the slope.The study highlights poor geological conditions as the decisive factor for this landslide,with continuous heavy rainfall as the triggering factor.Presently,adverse environmental factors persistently affect the landslide,and deformation and failure continue to escalate.Hence,it is imperative to urgently implement integrated measures encompassing slope reinforcement,monitoring,and early-warning to real-time monitor the landslide's deformation and deep mechanical evolution trends. 展开更多
关键词 Landslide development process Extra-large landslide Heavy rainfall Failure characteristics Instability mechanism Landslide monitoring and early-warning
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Depositional process of hyperpycnal flow deposits:A case study on Lower Cretaceous Sangyuan outcrop in the Luanping Basin,Northeast China
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作者 De-zhi Yan Ru-kai Zhu +8 位作者 Hao Shou Zhao-hui Xu Wei-hong Liu Si-cheng Zhu Zhi-cheng Lei Jing-ya Zhang Chang Liu Yi Cai Huai-min Xu 《China Geology》 CAS CSCD 2024年第3期505-516,共12页
Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this... Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits. 展开更多
关键词 Hyperpycnal flow Sedimentary characteristics Depositional process Gravity flow deposit Hyperpycnite Red mud pebble Gray mud pebble Oil and gas exploration engineering Luanping Basin
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Study on transient aerodynamic characteristics of parachute opening process 被引量:20
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作者 Li Yu Xiao Ming 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第6期627-633,共7页
In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficu... In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficulty for theoretical analysis and experimental measurements. In this paper, aerodynamic equations and structural dynamics equations were developed for describing parachute opening process, and an iterative coupling solving strategy incorpo- rating the above equations was proposed for a small-scale, flexible and flat-circular parachute. Then, analyses were carried out for canopy geometry, time-dependent pressure difference between the inside and outside of the canopy, transient vortex around the canopy and the flow field in the radial plane as a sequence in opening process. The mechanism of the canopy shape development was explained from perspective of transient flow fields during the inflation process. Experiments of the parachute opening process were conducted in a wind tunnel, in which instantaneous shape of the canopy was measured by high velocity camera and the opening loading was measured by dynamometer balance. The theoretical predictions were found in good agreement with the experimental results, validating the proposed approach. This numerical method can improve the situation of strong dependence of parachute research on wind tunnel tests, and is of significance to the understanding of the mechanics of parachute inflation process. 展开更多
关键词 PARACHUTE Opening process Numerical simulation Flow field characteristics AERODYNAMICS Structural dynamics
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Characteristics and Process of Land Use Changes in the Yangtze River Delta, China 被引量:17
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作者 PULIJIE YANGGUISHAN 《Pedosphere》 SCIE CAS CSCD 2001年第3期193-198,共6页
As one of the developing countries China has an arable land per capita far below the world’s average level. With a high-density population and the quick development of economy and urbanization, the Yangtze River Delt... As one of the developing countries China has an arable land per capita far below the world’s average level. With a high-density population and the quick development of economy and urbanization, the Yangtze River Delta shows the typical characteristics of land use in developed regions of China, which are: high land reclamation rate and low arable land per capita; intensive land use and high output value; and rapid increasing of construction land area and fast diminishing of arable lands. The analysis indicates that the process of the arable land changes in the Yangtze River Delta could be divided into four different change stages over the past 50 years. 展开更多
关键词 arable land use characteristics CHANGE process the Yangtze River Delta
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Basic characteristics of Australian iron ore concentrate and its effects on sinter properties during the high-limonite sintering process 被引量:7
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作者 Dong-hui Liu Hao Liu +4 位作者 Jian-liang Zhang Zheng-jian Liu Xun Xue Guang-wei Wang Qing-feng Kang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第9期991-998,共8页
The basic characteristics of Australian iron ore concentrate (Ore-A) and its effects on sinter properties during a high-limonite sintering process were studied using micro-sinter and sinter pot methods. The results sh... The basic characteristics of Australian iron ore concentrate (Ore-A) and its effects on sinter properties during a high-limonite sintering process were studied using micro-sinter and sinter pot methods. The results show that the Ore-A exhibits good granulation properties, strong liquid flow capability, high bonding phase strength and crystal strength, but poor assimilability. With increasing Ore-A ratio, the tumbler index and the reduction index (RI) of the sinter first increase and then decrease, whereas the softening interval (Delta T) and the softening start temperature (T (10%)) of the sinter exhibit the opposite behavior; the reduction degradation index (RDI+3.15) of the sinter increases linearly, but the sinter yield exhibits no obvious effects. With increasing Ore-A ratio, the distribution and crystallization of the minerals are improved, the main bonding phase first changes from silico-ferrite of calcium and aluminum (SFCA) to kirschsteinite, silicate, and SFCA and then transforms to 2CaO center dot SiO2 and SFCA. Given the utilization of Ore-A and the improvement of the sinter properties, the Ore-A ratio in the high-limonite sintering process is suggested to be controlled at approximately 6wt%. 展开更多
关键词 iron ore concentrate LIMONITE basic characteristics sinter properties sintering process
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Effect of Ultra High Pressure Processing on the Particle Characteristics of Lotus-seed Starch 被引量:9
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作者 郭泽镔 刘文婷 +1 位作者 曾绍校 郑宝东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第4期525-532,共8页
In this paper, the time dependent effects of various pressure treatments on the characteristics of lotus-seed starch which was modified by ultra-high pressure (UHP) were investigated. The results showed that the pol... In this paper, the time dependent effects of various pressure treatments on the characteristics of lotus-seed starch which was modified by ultra-high pressure (UHP) were investigated. The results showed that the polarization cross of lotus-seed starch granules was weakening gradually with increasing the treatment time, which indicated the termination of their ordered crystallite structures. The morphologies of granules were collapsed once the UHP was kept at 500 MPa for 60 minutes. The particle size analysis demonstrated that the granule size and distribution of lotus-seed starches increased as the treatment time was prolonged. X-ray diffraction studies showed that the intensity of the feature diffraction peaks of starch decreased and eventually disappeared with increasing the treatment time, and B-type transformation pattern was observed. The Fourier transform infrared spectra (FTIR) analysis of starch showed that the UHP is a physical modification processing because no new groups formed. The research showed that UHP processing at certain degree is capable to achieve the modification of lotus-seed starch. It is of significance for the deep processing of lotus-seed products. 展开更多
关键词 lotus-seed starch ultra high pressure particle characteristics food processing
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Electrochemical reduction characteristics and mechanism of nitrobenzene compounds in the catalyzed Fe-Cu process 被引量:7
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作者 XU Wen-ying FAN Jin-hong GAO Ting-yao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第2期379-387,共9页
The reduction of the nitrobenzene compounds (NBCs) by the catalyzed Fe-Cu process and the relationship between the electrochemical reduction characteristics of NBCs at copper electrode and reduction rate were studie... The reduction of the nitrobenzene compounds (NBCs) by the catalyzed Fe-Cu process and the relationship between the electrochemical reduction characteristics of NBCs at copper electrode and reduction rate were studied in alkaline medium(pH=11). The catalyzed Fe-Cu process was found more effective on degradation of NBCs compared to Master Builder's iron. The reduction rate by the catalyzed Fe-Cu process decreased in the following order: nitrobenzene 〉4-chloro-nitrobenzene ≥m-dinitrobenzene :〉 4-nitrophenol ≥2,4-dinitrotoluene 〉2-nitrophenol. The reduction rate by Master Builder's iron decreased in the following order: m-dinitrobenzene ≥4-chloro-nitrobenzene 〉4-nitrophenol 〉2,4-dinitrotoluene ≈nitrobenzene 〉2-nitrophenol. NBCs were reduced directly on the surface of copper rather than by the hydrogen produced at cathode in the catalyzed Fe-Cu process. The reduction was realized by the hydrogen produced at cathode and Fe(OH)2 in Master Builder's iron, It is an essential difference in reaction mechanisms between these two technologies. For this reason, the reduction by the catalyzed Fe-Cu depended greatly on NBC's electron withdrawing ability. 展开更多
关键词 wastewater contaminated by NBCs electrochemical reduction characteristics catalyzed Fe-Cu process reduction mechanism
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Review on the processing characteristics of cereals and oilseeds and their processing suitability evaluation technology 被引量:4
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作者 WANG Qiang LIU Hong-zhi +4 位作者 SHI Ai-min HU Hui LIU Li WANG Li YU Hong-wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第12期2886-2897,共12页
Cereals and oilseeds are the foundation of human survival which have attracted much attention due to their nutritional and functional properties for maintaining the healthy life. There are abundant varieties of cereal... Cereals and oilseeds are the foundation of human survival which have attracted much attention due to their nutritional and functional properties for maintaining the healthy life. There are abundant varieties of cereals and oilseeds, however, for a long time, their process suitabilities are still unknown, resulting in the lack of precision processing. This paper summarized the characteristics of cereals and oilseeds, including sensory, physicochemical and processing qualities, their characteristic fingerprinting and products qualities. Furthermore, the quality fast detection method was also analyzed. It also explored the role of mathematical model and the standard evaluation index to determine the process suitability and discussed the opportunity for advanced model capability. We also prospected on scientific problems for expanding the predictive capabilities for processing suitabilities of these abundant varieties, focusing on the better results and advancements towards the processing of cereals and oilseeds products and improvement of their quality. 展开更多
关键词 cereal and oilseeds processing characteristics quality evaluation
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Analysis of Energy Characteristics in the Process of Freak Wave Generation 被引量:2
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作者 胡金鹏 张运秋 《China Ocean Engineering》 SCIE EI CSCD 2014年第2期193-205,共13页
The energy characteristics in the evolution of the wave train are investigated to understand the inherent cause of the freak wave generation. The Morlet wavelet spectrum method is employed to analyze the numerical, la... The energy characteristics in the evolution of the wave train are investigated to understand the inherent cause of the freak wave generation. The Morlet wavelet spectrum method is employed to analyze the numerical, laboratory and field evolution data of this generation process. Their energy distributions and variations are discussed with consideration of corresponding surface elevations. Through comparing the energy characteristics of three cases, it is shown that the freak wave generation depends not only on the continuous transfer of wave train energy to a certain region where finally the maximum energy occurs, but also on the distinct shift of the converged energy to high-frequency components in a very short time. And the typical energy characteristics of freak waves are also given. 展开更多
关键词 freak wave generation process wavelet spectrum energy characteristics
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Seasonal freezing-thawing process and hydrothermal characteristics of soil on the Loess Plateau, China 被引量:3
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作者 CHOU Ya-ling WANG Li-jie 《Journal of Mountain Science》 SCIE CSCD 2021年第11期3082-3098,共17页
In seasonally frozen soil regions,freezing-thawing action and hydrothermal effect have strong influence on physical and mechanical behavior of shallow soil.A field experiment on the Loess Plateau in Northwest China wa... In seasonally frozen soil regions,freezing-thawing action and hydrothermal effect have strong influence on physical and mechanical behavior of shallow soil.A field experiment on the Loess Plateau in Northwest China was carried out to analyze the freezing-thawing process and hydrothermal characteristics of shallow soil considering the climate influence.The results show that the maximum seasonal freezing depth under bare ground surface in this area is from 20 cm to 50 cm.The ground temperature shows a similar changing trend with air temperature,but it has lagged behind the air temperature,and the ground temperature amplitude exponentially decreases with the increase of soil depth.The seasonally frozen soil has experienced four typical stages:unfrozen period,alternate freezing period,freezing period and alternate thawing period.The freezing-thawing process is characterized by unidirectional freezing and bidirectional thawing.The water content of shallow soil is significantly affected by air temperature,evaporation and precipitation,and the soil water content shows a"low-high-low"changing trend with the increase of depth.The soil temperature and water content interact with each other,and are often coupled.The variation trend of soil moisture with time is consistent with the change trend of the ground temperature with time in each soil layer,andthe degree of consistency is higher in the near surface soil than that in the lower layer.Also,the spatial-temporal characteristics of soil moisture and temperature is that the volumetric water content and ground temperatureof near surface soil have strong variability,and the range valueKa and coefficient of variation Cvof soil water content and ground temperaturein different seasons show a decreasing trend with the increase of depth. 展开更多
关键词 Seasonally frozen soil Freezing-thawing process Hydrothermal characteristics Loess Plateau
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Mineralogical Characteristics of Exsolved Spinel in the Panzhihua V-Ti Magnetite Deposit, Sichuan: Implications for the Mineralization Process 被引量:2
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作者 ZHANG Zhibin HUANG Fei +5 位作者 XING Miaomiao WAN Quan GAO Wenyuan GAO Shang CHEN Zhenyu CAI Jianhui 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期1784-1797,共14页
Spinel exsolution is widespread in titanomagnetite from the Fe-Ti oxide gabbro of the Panzhihua intrusion, Emeishan Large Igneous Province, SW China. However, little research has been conducted into the implications o... Spinel exsolution is widespread in titanomagnetite from the Fe-Ti oxide gabbro of the Panzhihua intrusion, Emeishan Large Igneous Province, SW China. However, little research has been conducted into the implications of patterns in the mineralogical characteristics of the spinel for spatial variation in the controls on the exsolution mechanism and, hence, the formation process of the ore deposit. This study selected the Lanjiahuoshan Ore Block in the Panzhihua V-Ti magnetite deposit to explore this issue, systematically studying exsolution textures in the titanomagnetite through petrographic observation and the integrated use of in-situ microanalysis. The results show that the exsolved spinel gradually becomes finer-grained and less abundant from the center to edge and the bottom to top of the ore bodies. Compositionally, there is an inverse correlation between the size of exsolved spinel grains and their Mg# value. In addition, there is compositional zonation in the spinel interiors, with a gradual increase in the Mg content and decrease in Fe content from the core to the rim. The analysis suggests that fractional crystallization of ferrotitanium magma with a high oxygen fugacity in a shallow magma chamber caused compositional differences in the primary magnetite solid solution in different parts of the Panzhihua intrusion. Additionally, the thermal evolution of the magnetite solid solution differed in different parts of orebody, bringing about variations in spinel development. Together, these effects resulted in spatial variation in the abundance, grain size, and morphology of spinel in different parts of the orebody and intrusion that follows an identifiable distribution law. Furthermore, the compositional zonation of exsolved spinels reflects the rapid growth of exsolution features in a high-temperature environment. Thus, the size, morphology, abundance, and composition of spinel exsolution features in titanomagnetite provide a valuable petrogenetic tool for estimating the maturity and formational environment of the deposit. 展开更多
关键词 spinel exsolution mineralogical characteristics compositional zonation mineralization process Panzhihua Sichuan
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Physical Characteristics of Welding Arc Ignition Process 被引量:1
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作者 SHI Linan SONG Yonglun XIAO Tianjiao RAN Guowei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期786-791,共6页
The existing research of welding arc mainly focuses on the stable combustion state and the research on the mechanism of welding arc ignition process is quite lack.The tungsten inert gas(TIG) touch arc ignition proce... The existing research of welding arc mainly focuses on the stable combustion state and the research on the mechanism of welding arc ignition process is quite lack.The tungsten inert gas(TIG) touch arc ignition process is observed via a high speed camera and the high time resolution spectral diagnosis system.The changing phenomenon of main ionized element provided the electrons in the arc ignition is found.The metallic element is the main contributor to provide the electrons at the beginning of the discharging,and then the excitated shielding gas element replaces the function of the metallic element.The electron density during the period of the arc ignition is calculated by the Stark-broadened lines of Hα.Through the discussion with the repeatability in relaxation phenomenon,the statistical regularity in the arc ignition process is analyzed.The similar rules as above are observed through the comparison with the laser-assisted arc ignition experiments and the metal inert gas(MIG) arc ignition experiments.This research is helpful to further understanding on the generation mechanism of welding arc ignition and also has a certain academic and practical significance on enriching the welding physical theoretical foundation and improving the precise monitoring on automatic arc welding process. 展开更多
关键词 welding arc ignition process physical characteristic spectral diagnosis
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Characteristics and Microstructure of a Hypereutectic Al-Si Alloy Powder by Ultrasonic Gas Atomization Process 被引量:3
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作者 Jun SHEN Zhuangde XIE Bide ZHOU and Qingchun LI School of Materials Science and Engineering, Harbin institute of Technology, Harbin 150O01. China Zhijun SU and Hongsheng LE Shanghai HitaChi Electrical Appliance Co. Ltd, Shanghai 201206, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第1期79-80,共2页
A hypereutectic Al-Si alloy powder was prepared by ultrasonic gas atomization process. The morphologies, microstructure and phase constituent of the alloy powder were studied. The results showed that powder of the all... A hypereutectic Al-Si alloy powder was prepared by ultrasonic gas atomization process. The morphologies, microstructure and phase constituent of the alloy powder were studied. The results showed that powder of the alloy was very fine and its microstructure was mainly consisted of Si crystals plus intermetallic compound A19FeSi3, which were.very fine and uniformly distributed. 展开更多
关键词 FESI characteristics and Microstructure of a Hypereutectic Al-Si Alloy Powder by Ultrasonic Gas Atomization process AL
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Analysis of the Flow Field Characteristics Associated with the Dynamic Rock Breaking Process Induced by a Multi-Hole Combined External Rotary Bit 被引量:3
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作者 Quanbin Ba Yanbao Liu +2 位作者 Zhigang Zhang Wei Xiong Kai Shen 《Fluid Dynamics & Materials Processing》 EI 2021年第4期697-710,共14页
The characteristics of the flow field associated with a multi-hole combined external rotary bit have been studied by means of numerical simulation in the framework of an RNG k-εturbulence model,and compared with the ... The characteristics of the flow field associated with a multi-hole combined external rotary bit have been studied by means of numerical simulation in the framework of an RNG k-εturbulence model,and compared with the results of dedicated rock breaking drilling experiments.The numerical results show that the nozzle velocity and dynamic pressure of the nozzle decrease with an increase in the jet distance,and the axial velocity of the nozzle decays regularly with an increase in the dimensionless jet distance.Moreover,the axial velocity related to the nozzle with inclination angle 20°and 30°can produce a higher hole depth,while the radial velocity of the nozzle with 60°inclination can enlarge the hole diameter.The outcomes of the CFD simulations are consistent with the actual dynamic rock breaking and pore forming process,which lends credence to the present results and indicates that they could be used as a reference for the future optimization of systems based on the multi-hole combined external rotary bit technology. 展开更多
关键词 External rotation nozzle RNG k-εturbulence model flow field characteristics rock breaking and hole forming process analysis
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An Experimental Study on Thermal Characteristics of Laurie Acid as a Latent Heat Storage Material during Melting Process 被引量:1
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作者 Ahmet SARI 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期240-243,共4页
The objective of this study was to establish the thermal characteristics of the lauric acid (95% purity) as a latent heat storage material filled in the annulus of vertical concentric double pipe during its melting pr... The objective of this study was to establish the thermal characteristics of the lauric acid (95% purity) as a latent heat storage material filled in the annulus of vertical concentric double pipe during its melting process,The temperature data were used to determine the thermal characteristics,including the temporal temperature variations and the effects of the mass flow rate and the inlet temperature of the heat transfer fluid on the heat transfer coefficient and the heat charging fraction during the melting process,The results indicated that the time to reach to heat charging fraction of 1.0 could be altered by changing the mass flow rate and the inlet temperature of the heat transfer fluid. 展开更多
关键词 lauric acid phase change material thermal characteristics melting process
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Sorption Characteristics of CO<sub>2</sub>on Rocks and Minerals in Storing CO<sub>2</sub>Processes 被引量:2
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作者 Takashi Fujii Satomi Nakagawa +2 位作者 Yoshiyuki Sato Hiroshi Inomata Toshiyuki Hashida 《Natural Resources》 2010年第1期1-10,共10页
As CO2 is injected into pore spaces of water-filled reservoir rocks, it displaces much of the pore fluids. In short terms (several to tens of years), the greater part of the injected CO2 is predicted to stay as free C... As CO2 is injected into pore spaces of water-filled reservoir rocks, it displaces much of the pore fluids. In short terms (several to tens of years), the greater part of the injected CO2 is predicted to stay as free CO2 , i.e. in a CO2 rich dense phase that may contain some water. This paper investigates the sorption characteristics for rocks (quartzose arenite, greywacke, shale, granite and serpentine) and minerals (quartz and albite) in the CO2 rich dense phase. The measurements were conducted at 50°C and 100°C, and pressures up to 20 MPa. Our results demonstrated that significant quantities of CO2 were sorbed with all the samples. Particularly, at 50°C and 100°C, quartzose arenite showed largest sorption capacity among the other samples in higher pressures (>10 MPa). Furthermore, comparison with model prediction based on the pore filling model, which assumed that CO2 acts as filling pore spaces of the rocks and minerals, suggested the importance of the sorption mechanism in the CO2 geological storage in addition to the pore-filling mechanism. The present results should be pointed out that the sorption characteristics may have significant and meaningful effect on the assessment of CO2 storage capacity in geological media. 展开更多
关键词 Sorption characteristics Rocks Minerals Storing CO2 processES CO2 GEOLOGICAL Storage
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